Class ZCL_IBMC_SPEECH_TO_TEXT

Class ZCL_IBMC_SPEECH_TO_TEXT_V1

public inheriting from zcl_ibmc_service_ext create public

Documentation

Speech to Text

The IBM Watson™ Speech to Text service provides APIs that use IBM's speech-recognition capabilities to produce transcripts of spoken audio. The service can transcribe speech from various languages and audio formats. In addition to basic transcription, the service can produce detailed information about many different aspects of the audio. It returns all JSON response content in the UTF-8 character set.

The service supports two types of models: previous-generation models that include the terms `Broadband` and `Narrowband` in their names, and next-generation models that include the terms `Multimedia` and `Telephony` in their names. Broadband and multimedia models have minimum sampling rates of 16 kHz. Narrowband and telephony models have minimum sampling rates of 8 kHz. The next-generation models offer high throughput and greater transcription accuracy.

Effective **31 July 2023**, all previous-generation models will be removed from the service and the documentation. Most previous-generation models were deprecated on 15 March 2022. You must migrate to the equivalent next-generation model by 31 July 2023. For more information, see [Migrating to next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-m igrate).{: deprecated}

For speech recognition, the service supports synchronous and asynchronous HTTP Representational State Transfer (REST) interfaces. It also supports a WebSocket interface that provides a full-duplex, low-latency communication channel: Clients send requests and audio to the service and receive results over a single connection asynchronously.

The service also offers two customization interfaces. Use language model customization to expand the vocabulary of a base model with domain-specific terminology. Use acoustic model customization to adapt a base model for the acoustic characteristics of your audio. For language model customization, the service also supports grammars. A grammar is a formal language specification that lets you restrict the phrases that the service can recognize.

Language model customization and grammars are available for most previous- and next-generation models. Acoustic model customization is available for all previous-generation models.

Types

Visibility and Level	Name	Documentation
public	t_acoustic_model (structured type)	Information about an existing custom acoustic model.
public	t_acoustic_models (structured type)	Information about existing custom acoustic models.
public	t_audio_details (structured type)	Information about an audio resource from a custom acoustic model.
public	t_audio_listing (structured type)	Information about an audio resource from a custom acoustic model.
public	t_audio_metrics (structured type)	If audio metrics are requested, information about the signal characteristics of the input audio.
public	t_audio_metrics_details (structured type)	Detailed information about the signal characteristics of the input audio.
public	t_audio_metrics_histogram_bin (structured type)	A bin with defined boundaries that indicates the number of values in a range of signal characteristics for a histogram. The first and last bins of a histogram are the boundary bins. They cover the intervals between negative infinity and the first boundary, and between the last boundary and positive infinity, respectively.
public	t_audio_resource (structured type)	Information about an audio resource from a custom acoustic model.
public	t_audio_resources (structured type)	Information about the audio resources from a custom acoustic model.
public	t_corpora (structured type)	Information about the corpora from a custom language model.
public	t_corpus (structured type)	Information about a corpus from a custom language model.
public	t_create_acoustic_model (structured type)	Information about the new custom acoustic model.
public	t_create_language_model (structured type)	Information about the new custom language model.
public	t_custom_word (structured type)	Information about a word that is to be added to a custom language model.
public	t_custom_words (structured type)	Information about the words that are to be added to a custom language model.
public	t_empty_response_body type jsonobject	The empty response from a request.
public	t_error_model (structured type)	The error response from a failed request.
public	t_grammar (structured type)	Information about a grammar from a custom language model.
public	t_grammars (structured type)	Information about the grammars from a custom language model.
public	t_inline_object (structured type)	No documentation available.
public	t_keyword_result (structured type)	Information about a match for a keyword from speech recognition results.
public	t_language_model (structured type)	Information about an existing custom language model.
public	t_language_models (structured type)	Information about existing custom language models.
public	t_processed_audio (structured type)	Detailed timing information about the service's processing of the input audio.
public	t_processing_metrics (structured type)	If processing metrics are requested, information about the service's processing of the input audio. Processing metrics are not available with the synchronous [Recognize audio](#recognize) method.
public	t_recognition_job (structured type)	Information about a current asynchronous speech recognition job.
public	t_recognition_jobs (structured type)	Information about current asynchronous speech recognition jobs.
public	t_register_status (structured type)	Information about a request to register a callback for asynchronous speech recognition.
public	t_spch_recognition_alternative (structured type)	An alternative transcript from speech recognition results.
public	t_speaker_labels_result (structured type)	Information about the speakers from speech recognition results.
public	t_speech_model (structured type)	Information about an available language model.
public	t_speech_models (structured type)	Information about the available language models.
public	t_speech_recognition_result (structured type)	Component results for a speech recognition request.
public	t_speech_recognition_results (structured type)	The complete results for a speech recognition request.
public	t_supported_features (structured type)	Indicates whether select service features are supported with the model.
public	t_training_response (structured type)	The response from training of a custom language or custom acoustic model.
public	t_training_warning (structured type)	A warning from training of a custom language or custom acoustic model.
public	t_word (structured type)	Information about a word from a custom language model.
public	t_words (structured type)	Information about the words from a custom language model.
public	t_word_alternative_result (structured type)	An alternative hypothesis for a word from speech recognition results.
public	t_word_alternative_results (structured type)	Information about alternative hypotheses for words from speech recognition results.
public	t_word_error (structured type)	An error associated with a word from a custom language model.

Constants

Visibility and Level	Name	Documentation
public static	c_abapname_dictionary (structured type)	Map ABAP identifiers to service identifiers.
public static	c_required_fields (structured type)	List of required fields per type.

Methods

Visibility and Level

Name

Documentation

public instance

add_audio
importing	i_customization_id	type string
	i_audio_name	type string
	i_audio_resource	type file
	i_content_type	type string default 'application/zip'
	i_contained_content_type	type string optional
	i_allow_overwrite	type boolean default c_boolean_false
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Add an audio resource

Adds an audio resource to a custom acoustic model. Add audio content that reflects the acoustic characteristics of the audio that you plan to transcribe. You must use credentials for the instance of the service that owns a model to add an audio resource to it. Adding audio data does not affect the custom acoustic model until you train the model for the new data by using the [Train a custom acoustic model](#trainacousticmodel) method.

You can add individual audio files or an archive file that contains multiple audio files. Adding multiple audio files via a single archive file is significantly more efficient than adding each file individually. You can add audio resources in any format that the service supports for speech recognition.

You can use this method to add any number of audio resources to a custom model by calling the method once for each audio or archive file. You can add multiple different audio resources at the same time. You must add a minimum of 10 minutes of audio that includes speech, not just silence, to a custom acoustic model before you can train it. No audio resource, audio- or archive-type, can be larger than 100 MB. To add an audio resource that has the same name as an existing audio resource, set the `allow_overwrite` parameter to `true`; otherwise, the request fails. A custom model can contain no more than 50 hours of audio (for IBM Cloud) or 200 hours of audio (for IBM Cloud Pak for Data). **Note:** For IBM Cloud, the maximum hours of audio for a custom acoustic model was reduced from 200 to 50 hours in August and September 2022. For more information, see [Maximum hours of audio](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-audioReso urces#audioMaximum).

The method is asynchronous. It can take several seconds or minutes to complete depending on the duration of the audio and, in the case of an archive file, the total number of audio files being processed. The service returns a 201 response code if the audio is valid. It then asynchronously analyzes the contents of the audio file or files and automatically extracts information about the audio such as its length, sampling rate, and encoding. You cannot submit requests to train or upgrade the model until the service's analysis of all audio resources for current requests completes.

To determine the status of the service's analysis of the audio, use the [Get an audio resource](#getaudio) method to poll the status of the audio. The method accepts the customization ID of the custom model and the name of the audio resource, and it returns the status of the resource. Use a loop to check the status of the audio every few seconds until it becomes `ok`.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**See also:** [Add audio to the custom acoustic model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-acoustic# addAudio).

### Content types for audio-type resources

You can add an individual audio file in any format that the service supports for speech recognition. For an audio-type resource, use the `Content-Type` parameter to specify the audio format (MIME type) of the audio file, including specifying the sampling rate, channels, and endianness where indicated.
* `audio/alaw` (Specify the sampling rate (`rate`) of the audio.)
* `audio/basic` (Use only with narrowband models.)
* `audio/flac`
* `audio/g729` (Use only with narrowband models.)
* `audio/l16` (Specify the sampling rate (`rate`) and optionally the number of channels (`channels`) and endianness (`endianness`) of the audio.)
* `audio/mp3`
* `audio/mpeg`
* `audio/mulaw` (Specify the sampling rate (`rate`) of the audio.)
* `audio/ogg` (The service automatically detects the codec of the input audio.)
* `audio/ogg;codecs=opus`
* `audio/ogg;codecs=vorbis`
* `audio/wav` (Provide audio with a maximum of nine channels.)
* `audio/webm` (The service automatically detects the codec of the input audio.)
* `audio/webm;codecs=opus`
* `audio/webm;codecs=vorbis`

The sampling rate of an audio file must match the sampling rate of the base model for the custom model: for broadband models, at least 16 kHz; for narrowband models, at least 8 kHz. If the sampling rate of the audio is higher than the minimum required rate, the service down-samples the audio to the appropriate rate. If the sampling rate of the audio is lower than the minimum required rate, the service labels the audio file as `invalid`.

**See also:** [Supported audio formats](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-audio-f ormats).

### Content types for archive-type resources

You can add an archive file (**.zip** or **.tar.gz** file) that contains audio files in any format that the service supports for speech recognition. For an archive-type resource, use the `Content-Type` parameter to specify the media type of the archive file:
* `application/zip` for a **.zip** file
* `application/gzip` for a **.tar.gz** file.

When you add an archive-type resource, the `Contained-Content-Type` header is optional depending on the format of the files that you are adding:
* For audio files of type `audio/alaw`, `audio/basic`, `audio/l16`, or `audio/mulaw`, you must use the `Contained-Content-Type` header to specify the format of the contained audio files. Include the `rate`, `channels`, and `endianness` parameters where necessary. In this case, all audio files contained in the archive file must have the same audio format.
* For audio files of all other types, you can omit the `Contained-Content-Type` header. In this case, the audio files contained in the archive file can have any of the formats not listed in the previous bullet. The audio files do not need to have the same format.

Do not use the `Contained-Content-Type` header when adding an audio-type resource.

### Naming restrictions for embedded audio files

The name of an audio file that is contained in an archive-type resource can include a maximum of 128 characters. This includes the file extension and all elements of the name (for example, slashes).

Parameters

i_customization_id	The customization ID (GUID) of the custom acoustic model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_audio_name	The name of the new audio resource for the custom acoustic model. Use a localized name that matches the language of the custom model and reflects the contents of the resource. * Include a maximum of 128 characters in the name. * Do not use characters that need to be URL-encoded. For example, do not use spaces, slashes, backslashes, colons, ampersands, double quotes, plus signs, equals signs, questions marks, and so on in the name. (The service does not prevent the use of these characters. But because they must be URL-encoded wherever used, their use is strongly discouraged.) * Do not use the name of an audio resource that has already been added to the custom model.
i_audio_resource	The audio resource that is to be added to the custom acoustic model, an individual audio file or an archive file. With the `curl` command, use the `--data-binary` option to upload the file for the request.
i_content_type	For an audio-type resource, the format (MIME type) of the audio. For more information, see Content types for audio-type resources in the method description. For an archive-type resource, the media type of the archive file. For more information, see Content types for archive-type resources in the method description.
i_contained_content_type	_For an archive-type resource_, specify the format of the audio files that are contained in the archive file if they are of type `audio/alaw`, `audio/basic`, `audio/l16`, or `audio/mulaw`. Include the `rate`, `channels`, and `endianness` parameters where necessary. In this case, all audio files that are contained in the archive file must be of the indicated type. For all other audio formats, you can omit the header. In this case, the audio files can be of multiple types as long as they are not of the types listed in the previous paragraph. The parameter accepts all of the audio formats that are supported for use with speech recognition. For more information, see Content types for audio-type resources in the method description. _For an audio-type resource_, omit the header.
i_allow_overwrite	If `true`, the specified audio resource overwrites an existing audio resource with the same name. If `false`, the request fails if an audio resource with the same name already exists. The parameter has no effect if an audio resource with the same name does not already exist.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

add_corpus
importing	i_customization_id	type string
	i_corpus_name	type string
	i_corpus_file	type file
	i_allow_overwrite	type boolean default c_boolean_false
	i_corpus_file_ct	type string default zif_ibmc_service_arch~c_mediatype-all
	i_contenttype	type string default 'multipart/form-data'
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Add a corpus

Adds a single corpus text file of new training data to a custom language model. Use multiple requests to submit multiple corpus text files. You must use credentials for the instance of the service that owns a model to add a corpus to it. Adding a corpus does not affect the custom language model until you train the model for the new data by using the [Train a custom language model](#trainlanguagemodel) method.

Submit a plain text file that contains sample sentences from the domain of interest to enable the service to parse the words in context. The more sentences you add that represent the context in which speakers use words from the domain, the better the service's recognition accuracy.

The call returns an HTTP 201 response code if the corpus is valid. The service then asynchronously processes and automatically extracts data from the contents of the corpus. This operation can take on the order of minutes to complete depending on the current load on the service, the total number of words in the corpus, and, _for custom models that are based on previous-generation models_, the number of new (out-of-vocabulary) words in the corpus. You cannot submit requests to add additional resources to the custom model or to train the model until the service's analysis of the corpus for the current request completes. Use the [Get a corpus](#getcorpus) method to check the status of the analysis.

_For custom models that are based on previous-generation models_, the service auto-populates the model's words resource with words from the corpus that are not found in its base vocabulary. These words are referred to as out-of-vocabulary (OOV) words. After adding a corpus, you must validate the words resource to ensure that each OOV word's definition is complete and valid. You can use the [List custom words](#listwords) method to examine the words resource. You can use other words method to eliminate typos and modify how words are pronounced and displayed as needed.

To add a corpus file that has the same name as an existing corpus, set the `allow_overwrite` parameter to `true`; otherwise, the request fails. Overwriting an existing corpus causes the service to process the corpus text file and extract its data anew. _For a custom model that is based on a previous-generation model_, the service first removes any OOV words that are associated with the existing corpus from the model's words resource unless they were also added by another corpus or grammar, or they have been modified in some way with the [Add custom words](#addwords) or [Add a custom word](#addword) method.

The service limits the overall amount of data that you can add to a custom model to a maximum of 10 million total words from all sources combined. _For a custom model that is based on a previous-generation model_, you can add no more than 90 thousand custom (OOV) words to a model. This includes words that the service extracts from corpora and grammars, and words that you add directly.

**See also:**
* [Add a corpus to the custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-languageC reate#addCorpus)
* [Working with corpora for previous-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords#workingCorpora)
* [Working with corpora for next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords-ng#workingCorpora-ng)
* [Validating a words resource for previous-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords#validateModel)
* [Validating a words resource for next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords-ng#validateModel-ng)

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_corpus_name	The name of the new corpus for the custom language model. Use a localized name that matches the language of the custom model and reflects the contents of the corpus. * Include a maximum of 128 characters in the name. * Do not use characters that need to be URL-encoded. For example, do not use spaces, slashes, backslashes, colons, ampersands, double quotes, plus signs, equals signs, questions marks, and so on in the name. (The service does not prevent the use of these characters. But because they must be URL-encoded wherever used, their use is strongly discouraged.) * Do not use the name of an existing corpus or grammar that is already defined for the custom model. * Do not use the name `user`, which is reserved by the service to denote custom words that are added or modified by the user. * Do not use the name `base_lm` or `default_lm`. Both names are reserved for future use by the service.
i_corpus_file	A plain text file that contains the training data for the corpus. Encode the file in UTF-8 if it contains non-ASCII characters; the service assumes UTF-8 encoding if it encounters non-ASCII characters. Make sure that you know the character encoding of the file. You must use that same encoding when working with the words in the custom language model. For more information, see [Character encoding for custom words](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageWor ds#charEncoding). With the `curl` command, use the `--data-binary` option to upload the file for the request.
i_allow_overwrite	If `true`, the specified corpus overwrites an existing corpus with the same name. If `false`, the request fails if a corpus with the same name already exists. The parameter has no effect if a corpus with the same name does not already exist.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

add_grammar
importing	i_customization_id	type string
	i_grammar_name	type string
	i_grammar_file	type file
	i_content_type	type string default 'application/srgs'
	i_allow_overwrite	type boolean default c_boolean_false
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Add a grammar

Adds a single grammar file to a custom language model. Submit a plain text file in UTF-8 format that defines the grammar. Use multiple requests to submit multiple grammar files. You must use credentials for the instance of the service that owns a model to add a grammar to it. Adding a grammar does not affect the custom language model until you train the model for the new data by using the [Train a custom language model](#trainlanguagemodel) method.

The call returns an HTTP 201 response code if the grammar is valid. The service then asynchronously processes the contents of the grammar and automatically extracts new words that it finds. This operation can take a few seconds or minutes to complete depending on the size and complexity of the grammar, as well as the current load on the service. You cannot submit requests to add additional resources to the custom model or to train the model until the service's analysis of the grammar for the current request completes. Use the [Get a grammar](#getgrammar) method to check the status of the analysis.

_For grammars that are based on previous-generation models,_ the service populates the model's words resource with any word that is recognized by the grammar that is not found in the model's base vocabulary. These are referred to as out-of-vocabulary (OOV) words. You can use the [List custom words](#listwords) method to examine the words resource and use other words-related methods to eliminate typos and modify how words are pronounced as needed. _For grammars that are based on next-generation models,_ the service extracts no OOV words from the grammars.

To add a grammar that has the same name as an existing grammar, set the `allow_overwrite` parameter to `true`; otherwise, the request fails. Overwriting an existing grammar causes the service to process the grammar file and extract OOV words anew. Before doing so, it removes any OOV words associated with the existing grammar from the model's words resource unless they were also added by another resource or they have been modified in some way with the [Add custom words](#addwords) or [Add a custom word](#addword) method.

_For grammars that are based on previous-generation models,_ the service limits the overall amount of data that you can add to a custom model to a maximum of 10 million total words from all sources combined. Also, you can add no more than 90 thousand OOV words to a model. This includes words that the service extracts from corpora and grammars and words that you add directly.

**See also:**
* [Understanding grammars](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-gramma rUnderstand#grammarUnderstand)
* [Add a grammar to the custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-grammarAd d#addGrammar)
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_grammar_name	The name of the new grammar for the custom language model. Use a localized name that matches the language of the custom model and reflects the contents of the grammar. * Include a maximum of 128 characters in the name. * Do not use characters that need to be URL-encoded. For example, do not use spaces, slashes, backslashes, colons, ampersands, double quotes, plus signs, equals signs, questions marks, and so on in the name. (The service does not prevent the use of these characters. But because they must be URL-encoded wherever used, their use is strongly discouraged.) * Do not use the name of an existing grammar or corpus that is already defined for the custom model. * Do not use the name `user`, which is reserved by the service to denote custom words that are added or modified by the user. * Do not use the name `base_lm` or `default_lm`. Both names are reserved for future use by the service.
i_grammar_file	A plain text file that contains the grammar in the format specified by the `Content-Type` header. Encode the file in UTF-8 (ASCII is a subset of UTF-8). Using any other encoding can lead to issues when compiling the grammar or to unexpected results in decoding. The service ignores an encoding that is specified in the header of the grammar. With the `curl` command, use the `--data-binary` option to upload the file for the request.
i_content_type	The format (MIME type) of the grammar file: * `application/srgs` for Augmented Backus-Naur Form (ABNF), which uses a plain-text representation that is similar to traditional BNF grammars. * `application/srgs+xml` for XML Form, which uses XML elements to represent the grammar.
i_allow_overwrite	If `true`, the specified grammar overwrites an existing grammar with the same name. If `false`, the request fails if a grammar with the same name already exists. The parameter has no effect if a grammar with the same name does not already exist.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

add_word
importing	i_customization_id	type string
	i_word_name	type string
	i_custom_word	type t_custom_word
	i_contenttype	type string default 'application/json'
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Add a custom word

Adds a custom word to a custom language model. You can use this method to add a word or to modify an existing word in the words resource. _For custom models that are based on previous-generation models_, the service populates the words resource for a custom model with out-of-vocabulary (OOV) words from each corpus or grammar that is added to the model. You can use this method to modify OOV words in the model's words resource.

_For a custom model that is based on a previous-generation models_, the words resource for a model can contain a maximum of 90 thousand custom (OOV) words. This includes words that the service extracts from corpora and grammars and words that you add directly.

You must use credentials for the instance of the service that owns a model to add or modify a custom word for the model. Adding or modifying a custom word does not affect the custom model until you train the model for the new data by using the [Train a custom language model](#trainlanguagemodel) method.

Use the `word_name` parameter to specify the custom word that is to be added or modified. Use the `CustomWord` object to provide one or both of the optional `display_as` or `sounds_like` fields for the word.
* The `display_as` field provides a different way of spelling the word in a transcript. Use the parameter when you want the word to appear different from its usual representation or from its spelling in training data. For example, you might indicate that the word `IBM` is to be displayed as `IBM™`.
* The `sounds_like` field provides an array of one or more pronunciations for the word. Use the parameter to specify how the word can be pronounced by users. Use the parameter for words that are difficult to pronounce, foreign words, acronyms, and so on. For example, you might specify that the word `IEEE` can sound like `i triple e`. You can specify a maximum of five sounds-like pronunciations for a word. _For custom models that are based on previous-generation models_, if you omit the `sounds_like` field, the service attempts to set the field to its pronunciation of the word. It cannot generate a pronunciation for all words, so you must review the word's definition to ensure that it is complete and valid.

If you add a custom word that already exists in the words resource for the custom model, the new definition overwrites the existing data for the word. If the service encounters an error, it does not add the word to the words resource. Use the [Get a custom word](#getword) method to review the word that you add.

**See also:**
* [Add words to the custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-languageC reate#addWords)
* [Working with custom words for previous-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords#workingWords)
* [Working with custom words for next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords-ng#workingWords-ng)
* [Validating a words resource for previous-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords#validateModel)
* [Validating a words resource for next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords-ng#validateModel-ng)

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_word_name	The custom word that is to be added to or updated in the custom language model. Do not include spaces in the word. Use a `-` (dash) or `_` (underscore) to connect the tokens of compound words. URL-encode the word if it includes non-ASCII characters. For more information, see [Character encoding](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corpor aWords#charEncoding).
i_custom_word	A `CustomWord` object that provides information about the specified custom word. Specify an empty object to add a word with no sounds-like or display-as information.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

add_words
importing	i_customization_id	type string
	i_custom_words	type t_custom_words
	i_contenttype	type string default 'application/json'
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Add custom words

Adds one or more custom words to a custom language model. You can use this method to add words or to modify existing words in a custom model's words resource. _For custom models that are based on previous-generation models_, the service populates the words resource for a custom model with out-of-vocabulary (OOV) words from each corpus or grammar that is added to the model. You can use this method to modify OOV words in the model's words resource.

_For a custom model that is based on a previous-generation model_, the words resource for a model can contain a maximum of 90 thousand custom (OOV) words. This includes words that the service extracts from corpora and grammars and words that you add directly.

You must use credentials for the instance of the service that owns a model to add or modify custom words for the model. Adding or modifying custom words does not affect the custom model until you train the model for the new data by using the [Train a custom language model](#trainlanguagemodel) method.

You add custom words by providing a `CustomWords` object, which is an array of `CustomWord` objects, one per word. Use the object's `word` parameter to identify the word that is to be added. You can also provide one or both of the optional `display_as` or `sounds_like` fields for each word.
* The `display_as` field provides a different way of spelling the word in a transcript. Use the parameter when you want the word to appear different from its usual representation or from its spelling in training data. For example, you might indicate that the word `IBM` is to be displayed as `IBM™`.
* The `sounds_like` field provides an array of one or more pronunciations for the word. Use the parameter to specify how the word can be pronounced by users. Use the parameter for words that are difficult to pronounce, foreign words, acronyms, and so on. For example, you might specify that the word `IEEE` can sound like `I triple E`. You can specify a maximum of five sounds-like pronunciations for a word. _For a custom model that is based on a previous-generation model_, if you omit the `sounds_like` field, the service attempts to set the field to its pronunciation of the word. It cannot generate a pronunciation for all words, so you must review the word's definition to ensure that it is complete and valid.

If you add a custom word that already exists in the words resource for the custom model, the new definition overwrites the existing data for the word. If the service encounters an error with the input data, it returns a failure code and does not add any of the words to the words resource.

The call returns an HTTP 201 response code if the input data is valid. It then asynchronously processes the words to add them to the model's words resource. The time that it takes for the analysis to complete depends on the number of new words that you add but is generally faster than adding a corpus or grammar.

You can monitor the status of the request by using the [Get a custom language model](#getlanguagemodel) method to poll the model's status. Use a loop to check the status every 10 seconds. The method returns a `Customization` object that includes a `status` field. A status of `ready` means that the words have been added to the custom model. The service cannot accept requests to add new data or to train the model until the existing request completes.

You can use the [List custom words](#listwords) or [Get a custom word](#getword) method to review the words that you add. Words with an invalid `sounds_like` field include an `error` field that describes the problem. You can use other words-related methods to correct errors, eliminate typos, and modify how words are pronounced as needed.

**See also:**
* [Add words to the custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-languageC reate#addWords)
* [Working with custom words for previous-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords#workingWords)
* [Working with custom words for next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords-ng#workingWords-ng)
* [Validating a words resource for previous-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords#validateModel)
* [Validating a words resource for next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corporaW ords-ng#validateModel-ng)

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_custom_words	A `CustomWords` object that provides information about one or more custom words that are to be added to or updated in the custom language model.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

check_job
importing	i_id	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_recognition_job
raising	zcx_ibmc_service_exception

Check a job

Returns information about the specified job. The response always includes the status of the job and its creation and update times. If the status is `completed`, the response includes the results of the recognition request. You must use credentials for the instance of the service that owns a job to list information about it.

You can use the method to retrieve the results of any job, regardless of whether it was submitted with a callback URL and the `recognitions.completed_with_results` event, and you can retrieve the results multiple times for as long as they remain available. Use the [Check jobs](#checkjobs) method to request information about the most recent jobs associated with the calling credentials.

**See also:** [Checking the status and retrieving the results of a job](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-async#job).

Parameters

i_id	The identifier of the asynchronous job that is to be used for the request. You must make the request with credentials for the instance of the service that owns the job.
e_response	Service return value of type T_RECOGNITION_JOB

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

check_jobs
importing	i_accept	type string default 'application/json'
exporting	e_response	type t_recognition_jobs
raising	zcx_ibmc_service_exception

Check jobs

Returns the ID and status of the latest 100 outstanding jobs associated with the credentials with which it is called. The method also returns the creation and update times of each job, and, if a job was created with a callback URL and a user token, the user token for the job. To obtain the results for a job whose status is `completed` or not one of the latest 100 outstanding jobs, use the [Check a job[(#checkjob) method. A job and its results remain available until you delete them with the [Delete a job](#deletejob) method or until the job's time to live expires, whichever comes first.

**See also:** [Checking the status of the latest jobs](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-async#jobs ).

Parameters

e_response

Service return value of type T_RECOGNITION_JOBS

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

create_acoustic_model
importing	i_create_acoustic_model	type t_create_acoustic_model
	i_contenttype	type string default 'application/json'
	i_accept	type string default 'application/json'
exporting	e_response	type t_acoustic_model
raising	zcx_ibmc_service_exception

Create a custom acoustic model

Creates a new custom acoustic model for a specified base model. The custom acoustic model can be used only with the base model for which it is created. The model is owned by the instance of the service whose credentials are used to create it.

You can create a maximum of 1024 custom acoustic models per owning credentials. The service returns an error if you attempt to create more than 1024 models. You do not lose any models, but you cannot create any more until your model count is below the limit.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**Important:** Effective **31 July 2023**, all previous-generation models will be removed from the service and the documentation. Most previous-generation models were deprecated on 15 March 2022. You must migrate to the equivalent next-generation model by 31 July 2023. For more information, see [Migrating to next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-m igrate).

**See also:** [Create a custom acoustic model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-acoustic# createModel-acoustic).

Parameters

i_create_acoustic_model	A `CreateAcousticModel` object that provides basic information about the new custom acoustic model.
e_response	Service return value of type T_ACOUSTIC_MODEL

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

create_job
importing	i_audio	type file
	i_content_type	type string default 'application/octet-stream'
	i_model	type string default 'en-US_BroadbandModel'
	i_callback_url	type string optional
	i_events	type string optional
	i_user_token	type string optional
	i_results_ttl	type integer optional
	i_language_customization_id	type string optional
	i_acoustic_customization_id	type string optional
	i_base_model_version	type string optional
	i_customization_weight	type double optional
	i_inactivity_timeout	type integer default 30
	i_keywords	type tt_string optional
	i_keywords_threshold	type float optional
	i_max_alternatives	type integer default 1
	i_word_alternatives_threshold	type float optional
	i_word_confidence	type boolean default c_boolean_false
	i_timestamps	type boolean default c_boolean_false
	i_profanity_filter	type boolean default c_boolean_true
	i_smart_formatting	type boolean default c_boolean_false
	i_speaker_labels	type boolean default c_boolean_false
	i_grammar_name	type string optional
	i_redaction	type boolean default c_boolean_false
	i_processing_metrics	type boolean default c_boolean_false
	i_processing_metrics_interval	type float default '1.0'
	i_audio_metrics	type boolean default c_boolean_false
	i_end_of_phrase_silence_time	type double default '0.8'
	i_splt_trnscrpt_at_phrase_end	type boolean default c_boolean_false
	i_speech_detector_sensitivity	type float default '0.5'
	i_background_audio_suppression	type float default '0.0'
	i_low_latency	type boolean default c_boolean_false
	i_character_insertion_bias	type float default '0.0'
	i_accept	type string default 'application/json'
exporting	e_response	type t_recognition_job
raising	zcx_ibmc_service_exception

Create a job

Creates a job for a new asynchronous recognition request. The job is owned by the instance of the service whose credentials are used to create it. How you learn the status and results of a job depends on the parameters you include with the job creation request:
* By callback notification: Include the `callback_url` parameter to specify a URL to which the service is to send callback notifications when the status of the job changes. Optionally, you can also include the `events` and `user_token` parameters to subscribe to specific events and to specify a string that is to be included with each notification for the job.
* By polling the service: Omit the `callback_url`, `events`, and `user_token` parameters. You must then use the [Check jobs](#checkjobs) or [Check a job](#checkjob) methods to check the status of the job, using the latter to retrieve the results when the job is complete.

The two approaches are not mutually exclusive. You can poll the service for job status or obtain results from the service manually even if you include a callback URL. In both cases, you can include the `results_ttl` parameter to specify how long the results are to remain available after the job is complete. Using the HTTPS [Check a job](#checkjob) method to retrieve results is more secure than receiving them via callback notification over HTTP because it provides confidentiality in addition to authentication and data integrity.

The method supports the same basic parameters as other HTTP and WebSocket recognition requests. It also supports the following parameters specific to the asynchronous interface:
* `callback_url`
* `events`
* `user_token`
* `results_ttl`

You can pass a maximum of 1 GB and a minimum of 100 bytes of audio with a request. The service automatically detects the endianness of the incoming audio and, for audio that includes multiple channels, downmixes the audio to one-channel mono during transcoding. The method returns only final results; to enable interim results, use the WebSocket API. (With the `curl` command, use the `--data-binary` option to upload the file for the request.)

**See also:** [Creating a job](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-async#creat e).

### Streaming mode

For requests to transcribe live audio as it becomes available, you must set the `Transfer-Encoding` header to `chunked` to use streaming mode. In streaming mode, the service closes the connection (status code 408) if it does not receive at least 15 seconds of audio (including silence) in any 30-second period. The service also closes the connection (status code 400) if it detects no speech for `inactivity_timeout` seconds of streaming audio; use the `inactivity_timeout` parameter to change the default of 30 seconds.

**See also:**
* [Audio transmission](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-in put#transmission)
* [Timeouts](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-input #timeouts)

### Audio formats (content types)

The service accepts audio in the following formats (MIME types).
* For formats that are labeled **Required**, you must use the `Content-Type` header with the request to specify the format of the audio.
* For all other formats, you can omit the `Content-Type` header or specify `application/octet-stream` with the header to have the service automatically detect the format of the audio. (With the `curl` command, you can specify either `"Content-Type:"` or `"Content-Type: application/octet-stream"`.)

Where indicated, the format that you specify must include the sampling rate and can optionally include the number of channels and the endianness of the audio.
* `audio/alaw` (**Required.** Specify the sampling rate (`rate`) of the audio.)
* `audio/basic` (**Required.** Use only with narrowband models.)
* `audio/flac`
* `audio/g729` (Use only with narrowband models.)
* `audio/l16` (**Required.** Specify the sampling rate (`rate`) and optionally the number of channels (`channels`) and endianness (`endianness`) of the audio.)
* `audio/mp3`
* `audio/mpeg`
* `audio/mulaw` (**Required.** Specify the sampling rate (`rate`) of the audio.)
* `audio/ogg` (The service automatically detects the codec of the input audio.)
* `audio/ogg;codecs=opus`
* `audio/ogg;codecs=vorbis`
* `audio/wav` (Provide audio with a maximum of nine channels.)
* `audio/webm` (The service automatically detects the codec of the input audio.)
* `audio/webm;codecs=opus`
* `audio/webm;codecs=vorbis`

The sampling rate of the audio must match the sampling rate of the model for the recognition request: for broadband models, at least 16 kHz; for narrowband models, at least 8 kHz. If the sampling rate of the audio is higher than the minimum required rate, the service down-samples the audio to the appropriate rate. If the sampling rate of the audio is lower than the minimum required rate, the request fails.

**See also:** [Supported audio formats](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-audio-f ormats).

### Next-generation models

The service supports next-generation `Multimedia` (16 kHz) and `Telephony` (8 kHz) models for many languages. Next-generation models have higher throughput than the service's previous generation of `Broadband` and `Narrowband` models. When you use next-generation models, the service can return transcriptions more quickly and also provide noticeably better transcription accuracy.

You specify a next-generation model by using the `model` query parameter, as you do a previous-generation model. Most next-generation models support the `low_latency` parameter, and all next-generation models support the `character_insertion_bias` parameter. These parameters are not available with previous-generation models.

Next-generation models do not support all of the speech recognition parameters that are available for use with previous-generation models. Next-generation models do not support the following parameters:
* `acoustic_customization_id`
* `keywords` and `keywords_threshold`
* `processing_metrics` and `processing_metrics_interval`
* `word_alternatives_threshold`

**Important:** Effective **31 July 2023**, all previous-generation models will be removed from the service and the documentation. Most previous-generation models were deprecated on 15 March 2022. You must migrate to the equivalent next-generation model by 31 July 2023. For more information, see [Migrating to next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-m igrate).

**See also:**
* [Next-generation languages and models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-n g)
* [Supported features for next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-n g#models-ng-features)

Parameters

i_audio	The audio to transcribe.
i_content_type	The format (MIME type) of the audio. For more information about specifying an audio format, see Audio formats (content types) in the method description.
i_model	The model to use for speech recognition. If you omit the `model` parameter, the service uses the US English `en-US_BroadbandModel` by default. _For IBM Cloud Pak for Data,_ if you do not install the `en-US_BroadbandModel`, you must either specify a model with the request or specify a new default model for your installation of the service. See also: * [Using a model for speech recognition](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-mod els-use) * [Using the default model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-us e#models-use-default).
i_callback_url	A URL to which callback notifications are to be sent. The URL must already be successfully allowlisted by using the [Register a callback](#registercallback) method. You can include the same callback URL with any number of job creation requests. Omit the parameter to poll the service for job completion and results. Use the `user_token` parameter to specify a unique user-specified string with each job to differentiate the callback notifications for the jobs.
i_events	If the job includes a callback URL, a comma-separated list of notification events to which to subscribe. Valid events are * `recognitions.started` generates a callback notification when the service begins to process the job. * `recognitions.completed` generates a callback notification when the job is complete. You must use the [Check a job](#checkjob) method to retrieve the results before they time out or are deleted. * `recognitions.completed_with_results` generates a callback notification when the job is complete. The notification includes the results of the request. * `recognitions.failed` generates a callback notification if the service experiences an error while processing the job. The `recognitions.completed` and `recognitions.completed_with_results` events are incompatible. You can specify only of the two events. If the job includes a callback URL, omit the parameter to subscribe to the default events: `recognitions.started`, `recognitions.completed`, and `recognitions.failed`. If the job does not include a callback URL, omit the parameter.
i_user_token	If the job includes a callback URL, a user-specified string that the service is to include with each callback notification for the job; the token allows the user to maintain an internal mapping between jobs and notification events. If the job does not include a callback URL, omit the parameter.
i_results_ttl	The number of minutes for which the results are to be available after the job has finished. If not delivered via a callback, the results must be retrieved within this time. Omit the parameter to use a time to live of one week. The parameter is valid with or without a callback URL.
i_language_customization_id	The customization ID (GUID) of a custom language model that is to be used with the recognition request. The base model of the specified custom language model must match the model specified with the `model` parameter. You must make the request with credentials for the instance of the service that owns the custom model. By default, no custom language model is used. See [Using a custom language model for speech recognition](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-lan guageUse). Note: Use this parameter instead of the deprecated `customization_id` parameter.
i_acoustic_customization_id	The customization ID (GUID) of a custom acoustic model that is to be used with the recognition request. The base model of the specified custom acoustic model must match the model specified with the `model` parameter. You must make the request with credentials for the instance of the service that owns the custom model. By default, no custom acoustic model is used. See [Using a custom acoustic model for speech recognition](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-aco usticUse).
i_base_model_version	The version of the specified base model that is to be used with the recognition request. Multiple versions of a base model can exist when a model is updated for internal improvements. The parameter is intended primarily for use with custom models that have been upgraded for a new base model. The default value depends on whether the parameter is used with or without a custom model. See [Making speech recognition requests with upgraded custom models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-custom-u pgrade-use#custom-upgrade-use-recognition).
i_customization_weight	If you specify the customization ID (GUID) of a custom language model with the recognition request, the customization weight tells the service how much weight to give to words from the custom language model compared to those from the base model for the current request. Specify a value between 0.0 and 1.0. Unless a different customization weight was specified for the custom model when the model was trained, the default value is: * 0.3 for previous-generation models * 0.2 for most next-generation models * 0.1 for next-generation English and Japanese models A customization weight that you specify overrides a weight that was specified when the custom model was trained. The default value yields the best performance in general. Assign a higher value if your audio makes frequent use of OOV words from the custom model. Use caution when setting the weight: a higher value can improve the accuracy of phrases from the custom model's domain, but it can negatively affect performance on non-domain phrases. See [Using customization weight](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-language Use#weight).
i_inactivity_timeout	The time in seconds after which, if only silence (no speech) is detected in streaming audio, the connection is closed with a 400 error. The parameter is useful for stopping audio submission from a live microphone when a user simply walks away. Use `-1` for infinity. See [Inactivity timeout](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-input#t imeouts-inactivity).
i_keywords	An array of keyword strings to spot in the audio. Each keyword string can include one or more string tokens. Keywords are spotted only in the final results, not in interim hypotheses. If you specify any keywords, you must also specify a keywords threshold. Omit the parameter or specify an empty array if you do not need to spot keywords. You can spot a maximum of 1000 keywords with a single request. A single keyword can have a maximum length of 1024 characters, though the maximum effective length for double-byte languages might be shorter. Keywords are case-insensitive. See [Keyword spotting](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-spotti ng#keyword-spotting).
i_keywords_threshold	A confidence value that is the lower bound for spotting a keyword. A word is considered to match a keyword if its confidence is greater than or equal to the threshold. Specify a probability between 0.0 and 1.0. If you specify a threshold, you must also specify one or more keywords. The service performs no keyword spotting if you omit either parameter. See [Keyword spotting](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-spotti ng#keyword-spotting).
i_max_alternatives	The maximum number of alternative transcripts that the service is to return. By default, the service returns a single transcript. If you specify a value of `0`, the service uses the default value, `1`. See [Maximum alternatives](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-me tadata#max-alternatives).
i_word_alternatives_threshold	A confidence value that is the lower bound for identifying a hypothesis as a possible word alternative (also known as "Confusion Networks"). An alternative word is considered if its confidence is greater than or equal to the threshold. Specify a probability between 0.0 and 1.0. By default, the service computes no alternative words. See [Word alternatives](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-sp otting#word-alternatives).
i_word_confidence	If `true`, the service returns a confidence measure in the range of 0.0 to 1.0 for each word. By default, the service returns no word confidence scores. See [Word confidence](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-meta data#word-confidence).
i_timestamps	If `true`, the service returns time alignment for each word. By default, no timestamps are returned. See [Word timestamps](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-meta data#word-timestamps).
i_profanity_filter	If `true`, the service filters profanity from all output except for keyword results by replacing inappropriate words with a series of asterisks. Set the parameter to `false` to return results with no censoring. Note: The parameter can be used with US English and Japanese transcription only. See [Profanity filtering](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-forma tting#profanity-filtering).
i_smart_formatting	If `true`, the service converts dates, times, series of digits and numbers, phone numbers, currency values, and internet addresses into more readable, conventional representations in the final transcript of a recognition request. For US English, the service also converts certain keyword strings to punctuation symbols. By default, the service performs no smart formatting. Note: The parameter can be used with US English, Japanese, and Spanish (all dialects) transcription only. See [Smart formatting](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-form atting#smart-formatting).
i_speaker_labels	If `true`, the response includes labels that identify which words were spoken by which participants in a multi-person exchange. By default, the service returns no speaker labels. Setting `speaker_labels` to `true` forces the `timestamps` parameter to be `true`, regardless of whether you specify `false` for the parameter. * _For previous-generation models,_ the parameter can be used with Australian English, US English, German, Japanese, Korean, and Spanish (both broadband and narrowband models) and UK English (narrowband model) transcription only. * _For next-generation models,_ the parameter can be used with Czech, English (Australian, Indian, UK, and US), German, Japanese, Korean, and Spanish transcription only. See [Speaker labels](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-speaker- labels).
i_grammar_name	The name of a grammar that is to be used with the recognition request. If you specify a grammar, you must also use the `language_customization_id` parameter to specify the name of the custom language model for which the grammar is defined. The service recognizes only strings that are recognized by the specified grammar; it does not recognize other custom words from the model's words resource. See [Using a grammar for speech recognition](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-gra mmarUse).
i_redaction	If `true`, the service redacts, or masks, numeric data from final transcripts. The feature redacts any number that has three or more consecutive digits by replacing each digit with an `X` character. It is intended to redact sensitive numeric data, such as credit card numbers. By default, the service performs no redaction. When you enable redaction, the service automatically enables smart formatting, regardless of whether you explicitly disable that feature. To ensure maximum security, the service also disables keyword spotting (ignores the `keywords` and `keywords_threshold` parameters) and returns only a single final transcript (forces the `max_alternatives` parameter to be `1`). Note: The parameter can be used with US English, Japanese, and Korean transcription only. See [Numeric redaction](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-forma tting#numeric-redaction).
i_processing_metrics	If `true`, requests processing metrics about the service's transcription of the input audio. The service returns processing metrics at the interval specified by the `processing_metrics_interval` parameter. It also returns processing metrics for transcription events, for example, for final and interim results. By default, the service returns no processing metrics. See [Processing metrics](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-metrics #processing-metrics).
i_processing_metrics_interval	Specifies the interval in real wall-clock seconds at which the service is to return processing metrics. The parameter is ignored unless the `processing_metrics` parameter is set to `true`. The parameter accepts a minimum value of 0.1 seconds. The level of precision is not restricted, so you can specify values such as 0.25 and 0.125. The service does not impose a maximum value. If you want to receive processing metrics only for transcription events instead of at periodic intervals, set the value to a large number. If the value is larger than the duration of the audio, the service returns processing metrics only for transcription events. See [Processing metrics](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-metrics #processing-metrics).
i_audio_metrics	If `true`, requests detailed information about the signal characteristics of the input audio. The service returns audio metrics with the final transcription results. By default, the service returns no audio metrics. See [Audio metrics](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-metrics #audio-metrics).
i_end_of_phrase_silence_time	Specifies the duration of the pause interval at which the service splits a transcript into multiple final results. If the service detects pauses or extended silence before it reaches the end of the audio stream, its response can include multiple final results. Silence indicates a point at which the speaker pauses between spoken words or phrases. Specify a value for the pause interval in the range of 0.0 to 120.0. * A value greater than 0 specifies the interval that the service is to use for speech recognition. * A value of 0 indicates that the service is to use the default interval. It is equivalent to omitting the parameter. The default pause interval for most languages is 0.8 seconds; the default for Chinese is 0.6 seconds. See [End of phrase silence time](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-parsing#si lence-time).
i_splt_trnscrpt_at_phrase_end	If `true`, directs the service to split the transcript into multiple final results based on semantic features of the input, for example, at the conclusion of meaningful phrases such as sentences. The service bases its understanding of semantic features on the base language model that you use with a request. Custom language models and grammars can also influence how and where the service splits a transcript. By default, the service splits transcripts based solely on the pause interval. If the parameters are used together on the same request, `end_of_phrase_silence_time` has precedence over `split_transcript_at_phrase_end`. See [Split transcript at phrase end](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-parsing#spl it-transcript).
i_speech_detector_sensitivity	The sensitivity of speech activity detection that the service is to perform. Use the parameter to suppress word insertions from music, coughing, and other non-speech events. The service biases the audio it passes for speech recognition by evaluating the input audio against prior models of speech and non-speech activity. Specify a value between 0.0 and 1.0: * 0.0 suppresses all audio (no speech is transcribed). * 0.5 (the default) provides a reasonable compromise for the level of sensitivity. * 1.0 suppresses no audio (speech detection sensitivity is disabled). The values increase on a monotonic curve. Specifying one or two decimal places of precision (for example, `0.55`) is typically more than sufficient. The parameter is supported with all next-generation models and with most previous-generation models. See [Speech detector sensitivity](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-det ection#detection-parameters-sensitivity) and [Language model support](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-detecti on#detection-support).
i_background_audio_suppression	The level to which the service is to suppress background audio based on its volume to prevent it from being transcribed as speech. Use the parameter to suppress side conversations or background noise. Specify a value in the range of 0.0 to 1.0: * 0.0 (the default) provides no suppression (background audio suppression is disabled). * 0.5 provides a reasonable level of audio suppression for general usage. * 1.0 suppresses all audio (no audio is transcribed). The values increase on a monotonic curve. Specifying one or two decimal places of precision (for example, `0.55`) is typically more than sufficient. The parameter is supported with all next-generation models and with most previous-generation models. See [Background audio suppression](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-det ection#detection-parameters-suppression) and [Language model support](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-detecti on#detection-support).
i_low_latency	If `true` for next-generation `Multimedia` and `Telephony` models that support low latency, directs the service to produce results even more quickly than it usually does. Next-generation models produce transcription results faster than previous-generation models. The `low_latency` parameter causes the models to produce results even more quickly, though the results might be less accurate when the parameter is used. The parameter is not available for previous-generation `Broadband` and `Narrowband` models. It is available for most next-generation models. * For a list of next-generation models that support low latency, see [Supported next-generation language models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-n g#models-ng-supported). * For more information about the `low_latency` parameter, see [Low latency](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-interim #low-latency).
i_character_insertion_bias	For next-generation models, an indication of whether the service is biased to recognize shorter or longer strings of characters when developing transcription hypotheses. By default, the service is optimized to produce the best balance of strings of different lengths. The default bias is 0.0. The allowable range of values is -1.0 to 1.0. * Negative values bias the service to favor hypotheses with shorter strings of characters. * Positive values bias the service to favor hypotheses with longer strings of characters. As the value approaches -1.0 or 1.0, the impact of the parameter becomes more pronounced. To determine the most effective value for your scenario, start by setting the value of the parameter to a small increment, such as -0.1, -0.05, 0.05, or 0.1, and assess how the value impacts the transcription results. Then experiment with different values as necessary, adjusting the value by small increments. The parameter is not available for previous-generation models. See [Character insertion bias](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-parsing#in sertion-bias).
e_response	Service return value of type T_RECOGNITION_JOB

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

create_language_model
importing	i_create_language_model	type t_create_language_model
	i_contenttype	type string default 'application/json'
	i_accept	type string default 'application/json'
exporting	e_response	type t_language_model
raising	zcx_ibmc_service_exception

Create a custom language model

Creates a new custom language model for a specified base model. The custom language model can be used only with the base model for which it is created. The model is owned by the instance of the service whose credentials are used to create it.

You can create a maximum of 1024 custom language models per owning credentials. The service returns an error if you attempt to create more than 1024 models. You do not lose any models, but you cannot create any more until your model count is below the limit.

**Important:** Effective **31 July 2023**, all previous-generation models will be removed from the service and the documentation. Most previous-generation models were deprecated on 15 March 2022. You must migrate to the equivalent next-generation model by 31 July 2023. For more information, see [Migrating to next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-m igrate).

**See also:**
* [Create a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-languageC reate#createModel-language)
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)

Parameters

i_create_language_model	A `CreateLanguageModel` object that provides basic information about the new custom language model.
e_response	Service return value of type T_LANGUAGE_MODEL

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

delete_acoustic_model
importing	i_customization_id	type string
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Delete a custom acoustic model

Deletes an existing custom acoustic model. The custom model cannot be deleted if another request, such as adding an audio resource to the model, is currently being processed. You must use credentials for the instance of the service that owns a model to delete it.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**See also:** [Deleting a custom acoustic model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageAco usticModels#deleteModel-acoustic).

Parameters

i_customization_id

The customization ID (GUID) of the custom acoustic model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

delete_audio
importing	i_customization_id	type string
	i_audio_name	type string
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Delete an audio resource

Deletes an existing audio resource from a custom acoustic model. Deleting an archive-type audio resource removes the entire archive of files. The service does not allow deletion of individual files from an archive resource.

Removing an audio resource does not affect the custom model until you train the model on its updated data by using the [Train a custom acoustic model](#trainacousticmodel) method. You can delete an existing audio resource from a model while a different resource is being added to the model. You must use credentials for the instance of the service that owns a model to delete its audio resources.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**See also:** [Deleting an audio resource from a custom acoustic model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageAud io#deleteAudio).

Parameters

i_customization_id	The customization ID (GUID) of the custom acoustic model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_audio_name	The name of the audio resource for the custom acoustic model.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

delete_corpus
importing	i_customization_id	type string
	i_corpus_name	type string
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Delete a corpus

Deletes an existing corpus from a custom language model. Removing a corpus does not affect the custom model until you train the model with the [Train a custom language model](#trainlanguagemodel) method. You must use credentials for the instance of the service that owns a model to delete its corpora.

_For custom models that are based on previous-generation models_, the service removes any out-of-vocabulary (OOV) words that are associated with the corpus from the custom model's words resource unless they were also added by another corpus or grammar, or they were modified in some way with the [Add custom words](#addwords) or [Add a custom word](#addword) method.

**See also:** [Deleting a corpus from a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageCor pora#deleteCorpus).

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_corpus_name	The name of the corpus for the custom language model.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

delete_grammar
importing	i_customization_id	type string
	i_grammar_name	type string
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Delete a grammar

Deletes an existing grammar from a custom language model. _For grammars that are based on previous-generation models,_ the service removes any out-of-vocabulary (OOV) words associated with the grammar from the custom model's words resource unless they were also added by another resource or they were modified in some way with the [Add custom words](#addwords) or [Add a custom word](#addword) method. Removing a grammar does not affect the custom model until you train the model with the [Train a custom language model](#trainlanguagemodel) method. You must use credentials for the instance of the service that owns a model to delete its grammar.

**See also:**
* [Deleting a grammar from a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageGra mmars#deleteGrammar)
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_grammar_name	The name of the grammar for the custom language model.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

delete_job
importing	i_id	type string
raising	zcx_ibmc_service_exception

Delete a job

Deletes the specified job. You cannot delete a job that the service is actively processing. Once you delete a job, its results are no longer available. The service automatically deletes a job and its results when the time to live for the results expires. You must use credentials for the instance of the service that owns a job to delete it.

**See also:** [Deleting a job](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-async#delet e-async).

Parameters

i_id	The identifier of the asynchronous job that is to be used for the request. You must make the request with credentials for the instance of the service that owns the job.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

delete_language_model
importing	i_customization_id	type string
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Delete a custom language model

Deletes an existing custom language model. The custom model cannot be deleted if another request, such as adding a corpus or grammar to the model, is currently being processed. You must use credentials for the instance of the service that owns a model to delete it.

**See also:**
* [Deleting a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageLan guageModels#deleteModel-language)
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)

Parameters

i_customization_id

The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

delete_user_data
importing	i_customer_id	type string
raising	zcx_ibmc_service_exception

Delete labeled data

Deletes all data that is associated with a specified customer ID. The method deletes all data for the customer ID, regardless of the method by which the information was added. The method has no effect if no data is associated with the customer ID. You must issue the request with credentials for the same instance of the service that was used to associate the customer ID with the data. You associate a customer ID with data by passing the `X-Watson-Metadata` header with a request that passes the data.

**Note:** If you delete an instance of the service from the service console, all data associated with that service instance is automatically deleted. This includes all custom language models, corpora, grammars, and words; all custom acoustic models and audio resources; all registered endpoints for the asynchronous HTTP interface; and all data related to speech recognition requests.

**See also:** [Information security](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-inform ation-security#information-security).

Parameters

i_customer_id

The customer ID for which all data is to be deleted.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

delete_word
importing	i_customization_id	type string
	i_word_name	type string
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Delete a custom word

Deletes a custom word from a custom language model. You can remove any word that you added to the custom model's words resource via any means. However, if the word also exists in the service's base vocabulary, the service removes the word only from the words resource; the word remains in the base vocabulary. Removing a custom word does not affect the custom model until you train the model with the [Train a custom language model](#trainlanguagemodel) method. You must use credentials for the instance of the service that owns a model to delete its words.

**See also:** [Deleting a word from a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageWor ds#deleteWord).

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_word_name	The custom word that is to be deleted from the custom language model. URL-encode the word if it includes non-ASCII characters. For more information, see [Character encoding](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corpor aWords#charEncoding).

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

get_acoustic_model
importing	i_customization_id	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_acoustic_model
raising	zcx_ibmc_service_exception

Get a custom acoustic model

Gets information about a specified custom acoustic model. You must use credentials for the instance of the service that owns a model to list information about it.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**See also:** [Listing custom acoustic models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageAc ousticModels#listModels-acoustic).

Parameters

i_customization_id	The customization ID (GUID) of the custom acoustic model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
e_response	Service return value of type T_ACOUSTIC_MODEL

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

get_appname redefinition

public instance

get_audio
importing	i_customization_id	type string
	i_audio_name	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_audio_listing
raising	zcx_ibmc_service_exception

Get an audio resource

Gets information about an audio resource from a custom acoustic model. The method returns an `AudioListing` object whose fields depend on the type of audio resource that you specify with the method's `audio_name` parameter:
* _For an audio-type resource_, the object's fields match those of an `AudioResource` object: `duration`, `name`, `details`, and `status`.
* _For an archive-type resource_, the object includes a `container` field whose fields match those of an `AudioResource` object. It also includes an `audio` field, which contains an array of `AudioResource` objects that provides information about the audio files that are contained in the archive.

The information includes the status of the specified audio resource. The status is important for checking the service's analysis of a resource that you add to the custom model.
* _For an audio-type resource_, the `status` field is located in the `AudioListing` object.
* _For an archive-type resource_, the `status` field is located in the `AudioResource` object that is returned in the `container` field.

You must use credentials for the instance of the service that owns a model to list its audio resources.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**See also:** [Listing audio resources for a custom acoustic model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageAud io#listAudio).

Parameters

i_customization_id	The customization ID (GUID) of the custom acoustic model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_audio_name	The name of the audio resource for the custom acoustic model.
e_response	Service return value of type T_AUDIO_LISTING

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

get_corpus
importing	i_customization_id	type string
	i_corpus_name	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_corpus
raising	zcx_ibmc_service_exception

Get a corpus

Gets information about a corpus from a custom language model. The information includes the name, status, and total number of words for the corpus. _For custom models that are based on previous-generation models_, it also includes the number of out-of-vocabulary (OOV) words from the corpus. You must use credentials for the instance of the service that owns a model to list its corpora.

**See also:** [Listing corpora for a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageCor pora#listCorpora).

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_corpus_name	The name of the corpus for the custom language model.
e_response	Service return value of type T_CORPUS

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

get_grammar
importing	i_customization_id	type string
	i_grammar_name	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_grammar
raising	zcx_ibmc_service_exception

Get a grammar

Gets information about a grammar from a custom language model. For each grammar, the information includes the name, status, and (for grammars that are based on previous-generation models) the total number of out-of-vocabulary (OOV) words. You must use credentials for the instance of the service that owns a model to list its grammars.

**See also:**
* [Listing grammars from a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageGra mmars#listGrammars)
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_grammar_name	The name of the grammar for the custom language model.
e_response	Service return value of type T_GRAMMAR

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

get_language_model
importing	i_customization_id	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_language_model
raising	zcx_ibmc_service_exception

Get a custom language model

Gets information about a specified custom language model. You must use credentials for the instance of the service that owns a model to list information about it.

**See also:**
* [Listing custom language models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageLa nguageModels#listModels-language)
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
e_response	Service return value of type T_LANGUAGE_MODEL

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

get_model
importing	i_model_id	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_speech_model
raising	zcx_ibmc_service_exception

Get a model

Gets information for a single specified language model that is available for use with the service. The information includes the name of the model and its minimum sampling rate in Hertz, among other things.

**See also:** [Listing a specific model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-li st#models-list-specific).

Parameters

i_model_id	The identifier of the model in the form of its name from the output of the [List models](#listmodels) method.
e_response	Service return value of type T_SPEECH_MODEL

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

get_request_prop redefinition

public instance

get_sdk_version_date redefinition

public instance

get_word
importing	i_customization_id	type string
	i_word_name	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_word
raising	zcx_ibmc_service_exception

Get a custom word

Gets information about a custom word from a custom language model. You must use credentials for the instance of the service that owns a model to list information about its words.

**See also:** [Listing words from a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageWor ds#listWords).

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_word_name	The custom word that is to be read from the custom language model. URL-encode the word if it includes non-ASCII characters. For more information, see [Character encoding](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-corpor aWords#charEncoding).
e_response	Service return value of type T_WORD

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

list_acoustic_models
importing	i_language	type string optional
	i_accept	type string default 'application/json'
exporting	e_response	type t_acoustic_models
raising	zcx_ibmc_service_exception

List custom acoustic models

Lists information about all custom acoustic models that are owned by an instance of the service. Use the `language` parameter to see all custom acoustic models for the specified language. Omit the parameter to see all custom acoustic models for all languages. You must use credentials for the instance of the service that owns a model to list information about it.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**See also:** [Listing custom acoustic models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageAc ousticModels#listModels-acoustic).

Parameters

i_language

The identifier of the language for which custom language or custom acoustic models are to be returned. Specify the five-character language identifier; for example, specify `en-US` to see all custom language or custom acoustic models that are based on US English models. Omit the parameter to see all custom language or custom acoustic models that are owned by the requesting credentials.

To determine the languages for which customization is available, see [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support).

e_response

Service return value of type T_ACOUSTIC_MODELS

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

list_audio
importing	i_customization_id	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_audio_resources
raising	zcx_ibmc_service_exception

List audio resources

Lists information about all audio resources from a custom acoustic model. The information includes the name of the resource and information about its audio data, such as its duration. It also includes the status of the audio resource, which is important for checking the service's analysis of the resource in response to a request to add it to the custom acoustic model. You must use credentials for the instance of the service that owns a model to list its audio resources.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**See also:** [Listing audio resources for a custom acoustic model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageAud io#listAudio).

Parameters

i_customization_id	The customization ID (GUID) of the custom acoustic model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
e_response	Service return value of type T_AUDIO_RESOURCES

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

list_corpora
importing	i_customization_id	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_corpora
raising	zcx_ibmc_service_exception

List corpora

Lists information about all corpora from a custom language model. The information includes the name, status, and total number of words for each corpus. _For custom models that are based on previous-generation models_, it also includes the number of out-of-vocabulary (OOV) words from the corpus. You must use credentials for the instance of the service that owns a model to list its corpora.

**See also:** [Listing corpora for a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageCor pora#listCorpora).

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
e_response	Service return value of type T_CORPORA

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

list_grammars
importing	i_customization_id	type string
	i_accept	type string default 'application/json'
exporting	e_response	type t_grammars
raising	zcx_ibmc_service_exception

List grammars

Lists information about all grammars from a custom language model. For each grammar, the information includes the name, status, and (for grammars that are based on previous-generation models) the total number of out-of-vocabulary (OOV) words. You must use credentials for the instance of the service that owns a model to list its grammars.

**See also:**
* [Listing grammars from a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageGra mmars#listGrammars)
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
e_response	Service return value of type T_GRAMMARS

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

list_language_models
importing	i_language	type string optional
	i_accept	type string default 'application/json'
exporting	e_response	type t_language_models
raising	zcx_ibmc_service_exception

List custom language models

Lists information about all custom language models that are owned by an instance of the service. Use the `language` parameter to see all custom language models for the specified language. Omit the parameter to see all custom language models for all languages. You must use credentials for the instance of the service that owns a model to list information about it.

**See also:**
* [Listing custom language models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageLa nguageModels#listModels-language)
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)

Parameters

i_language

e_response

Service return value of type T_LANGUAGE_MODELS

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

list_models
importing	i_accept	type string default 'application/json'
exporting	e_response	type t_speech_models
raising	zcx_ibmc_service_exception

List models

Lists all language models that are available for use with the service. The information includes the name of the model and its minimum sampling rate in Hertz, among other things. The ordering of the list of models can change from call to call; do not rely on an alphabetized or static list of models.

**See also:** [Listing all models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-l ist#models-list-all).

Parameters

e_response

Service return value of type T_SPEECH_MODELS

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

list_words
importing	i_customization_id	type string
	i_word_type	type string default 'all'
	i_sort	type string default 'alphabetical'
	i_accept	type string default 'application/json'
exporting	e_response	type t_words
raising	zcx_ibmc_service_exception

List custom words

Lists information about custom words from a custom language model. You can list all words from the custom model's words resource, only custom words that were added or modified by the user, or, _for a custom model that is based on a previous-generation model_, only out-of-vocabulary (OOV) words that were extracted from corpora or are recognized by grammars. _For a custom model that is based on a next-generation model_, you can list all words or only those words that were added directly by a user, which return the same results.

You can also indicate the order in which the service is to return words; by default, the service lists words in ascending alphabetical order. You must use credentials for the instance of the service that owns a model to list information about its words.

**See also:** [Listing words from a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageWor ds#listWords).

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_word_type	The type of words to be listed from the custom language model's words resource: * `all` (the default) shows all words. * `user` shows only custom words that were added or modified by the user directly. * `corpora` shows only OOV that were extracted from corpora. * `grammars` shows only OOV words that are recognized by grammars. _For a custom model that is based on a next-generation model_, only `all` and `user` apply. Both options return the same results. Words from other sources are not added to custom models that are based on next-generation models.
i_sort	Indicates the order in which the words are to be listed, `alphabetical` or by `count`. You can prepend an optional `+` or `-` to an argument to indicate whether the results are to be sorted in ascending or descending order. By default, words are sorted in ascending alphabetical order. For alphabetical ordering, the lexicographical precedence is numeric values, uppercase letters, and lowercase letters. For count ordering, values with the same count are ordered alphabetically. With the `curl` command, URL-encode the `+` symbol as `%2B`.
e_response	Service return value of type T_WORDS

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

recognize
importing	i_audio	type file
	i_content_type	type string default 'application/octet-stream'
	i_model	type string default 'en-US_BroadbandModel'
	i_language_customization_id	type string optional
	i_acoustic_customization_id	type string optional
	i_base_model_version	type string optional
	i_customization_weight	type double optional
	i_inactivity_timeout	type integer default 30
	i_keywords	type tt_string optional
	i_keywords_threshold	type float optional
	i_max_alternatives	type integer default 1
	i_word_alternatives_threshold	type float optional
	i_word_confidence	type boolean default c_boolean_false
	i_timestamps	type boolean default c_boolean_false
	i_profanity_filter	type boolean default c_boolean_true
	i_smart_formatting	type boolean default c_boolean_false
	i_speaker_labels	type boolean default c_boolean_false
	i_grammar_name	type string optional
	i_redaction	type boolean default c_boolean_false
	i_audio_metrics	type boolean default c_boolean_false
	i_end_of_phrase_silence_time	type double default '0.8'
	i_splt_trnscrpt_at_phrase_end	type boolean default c_boolean_false
	i_speech_detector_sensitivity	type float default '0.5'
	i_background_audio_suppression	type float default '0.0'
	i_low_latency	type boolean default c_boolean_false
	i_character_insertion_bias	type float default '0.0'
	i_accept	type string default 'application/json'
exporting	e_response	type t_speech_recognition_results
raising	zcx_ibmc_service_exception

Recognize audio

Sends audio and returns transcription results for a recognition request. You can pass a maximum of 100 MB and a minimum of 100 bytes of audio with a request. The service automatically detects the endianness of the incoming audio and, for audio that includes multiple channels, downmixes the audio to one-channel mono during transcoding. The method returns only final results; to enable interim results, use the WebSocket API. (With the `curl` command, use the `--data-binary` option to upload the file for the request.)

**See also:** [Making a basic HTTP request](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-http#HT TP-basic).

### Streaming mode

For requests to transcribe live audio as it becomes available, you must set the `Transfer-Encoding` header to `chunked` to use streaming mode. In streaming mode, the service closes the connection (status code 408) if it does not receive at least 15 seconds of audio (including silence) in any 30-second period. The service also closes the connection (status code 400) if it detects no speech for `inactivity_timeout` seconds of streaming audio; use the `inactivity_timeout` parameter to change the default of 30 seconds.

**See also:**
* [Audio transmission](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-in put#transmission)
* [Timeouts](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-input #timeouts)

### Audio formats (content types)

The service accepts audio in the following formats (MIME types).
* For formats that are labeled **Required**, you must use the `Content-Type` header with the request to specify the format of the audio.
* For all other formats, you can omit the `Content-Type` header or specify `application/octet-stream` with the header to have the service automatically detect the format of the audio. (With the `curl` command, you can specify either `"Content-Type:"` or `"Content-Type: application/octet-stream"`.)

Where indicated, the format that you specify must include the sampling rate and can optionally include the number of channels and the endianness of the audio.
* `audio/alaw` (**Required.** Specify the sampling rate (`rate`) of the audio.)
* `audio/basic` (**Required.** Use only with narrowband models.)
* `audio/flac`
* `audio/g729` (Use only with narrowband models.)
* `audio/l16` (**Required.** Specify the sampling rate (`rate`) and optionally the number of channels (`channels`) and endianness (`endianness`) of the audio.)
* `audio/mp3`
* `audio/mpeg`
* `audio/mulaw` (**Required.** Specify the sampling rate (`rate`) of the audio.)
* `audio/ogg` (The service automatically detects the codec of the input audio.)
* `audio/ogg;codecs=opus`
* `audio/ogg;codecs=vorbis`
* `audio/wav` (Provide audio with a maximum of nine channels.)
* `audio/webm` (The service automatically detects the codec of the input audio.)
* `audio/webm;codecs=opus`
* `audio/webm;codecs=vorbis`

The sampling rate of the audio must match the sampling rate of the model for the recognition request: for broadband models, at least 16 kHz; for narrowband models, at least 8 kHz. If the sampling rate of the audio is higher than the minimum required rate, the service down-samples the audio to the appropriate rate. If the sampling rate of the audio is lower than the minimum required rate, the request fails.

**See also:** [Supported audio formats](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-audio-f ormats).

### Next-generation models

The service supports next-generation `Multimedia` (16 kHz) and `Telephony` (8 kHz) models for many languages. Next-generation models have higher throughput than the service's previous generation of `Broadband` and `Narrowband` models. When you use next-generation models, the service can return transcriptions more quickly and also provide noticeably better transcription accuracy.

You specify a next-generation model by using the `model` query parameter, as you do a previous-generation model. Most next-generation models support the `low_latency` parameter, and all next-generation models support the `character_insertion_bias` parameter. These parameters are not available with previous-generation models.

Next-generation models do not support all of the speech recognition parameters that are available for use with previous-generation models. Next-generation models do not support the following parameters:
* `acoustic_customization_id`
* `keywords` and `keywords_threshold`
* `processing_metrics` and `processing_metrics_interval`
* `word_alternatives_threshold`

**Important:** Effective **31 July 2023**, all previous-generation models will be removed from the service and the documentation. Most previous-generation models were deprecated on 15 March 2022. You must migrate to the equivalent next-generation model by 31 July 2023. For more information, see [Migrating to next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-m igrate).

**See also:**
* [Next-generation languages and models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-n g)
* [Supported features for next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-n g#models-ng-features)

### Multipart speech recognition

**Note:** The asynchronous HTTP interface, WebSocket interface, and Watson SDKs do not support multipart speech recognition.

The HTTP `POST` method of the service also supports multipart speech recognition. With multipart requests, you pass all audio data as multipart form data. You specify some parameters as request headers and query parameters, but you pass JSON metadata as form data to control most aspects of the transcription. You can use multipart recognition to pass multiple audio files with a single request.

Use the multipart approach with browsers for which JavaScript is disabled or when the parameters used with the request are greater than the 8 KB limit imposed by most HTTP servers and proxies. You can encounter this limit, for example, if you want to spot a very large number of keywords.

**See also:** [Making a multipart HTTP request](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-http#HT TP-multi).

Parameters

i_audio	The audio to transcribe.
i_content_type	The format (MIME type) of the audio. For more information about specifying an audio format, see Audio formats (content types) in the method description.
i_model	The model to use for speech recognition. If you omit the `model` parameter, the service uses the US English `en-US_BroadbandModel` by default. _For IBM Cloud Pak for Data,_ if you do not install the `en-US_BroadbandModel`, you must either specify a model with the request or specify a new default model for your installation of the service. See also: * [Using a model for speech recognition](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-mod els-use) * [Using the default model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-us e#models-use-default).
i_language_customization_id	The customization ID (GUID) of a custom language model that is to be used with the recognition request. The base model of the specified custom language model must match the model specified with the `model` parameter. You must make the request with credentials for the instance of the service that owns the custom model. By default, no custom language model is used. See [Using a custom language model for speech recognition](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-lan guageUse). Note: Use this parameter instead of the deprecated `customization_id` parameter.
i_acoustic_customization_id	The customization ID (GUID) of a custom acoustic model that is to be used with the recognition request. The base model of the specified custom acoustic model must match the model specified with the `model` parameter. You must make the request with credentials for the instance of the service that owns the custom model. By default, no custom acoustic model is used. See [Using a custom acoustic model for speech recognition](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-aco usticUse).
i_base_model_version	The version of the specified base model that is to be used with the recognition request. Multiple versions of a base model can exist when a model is updated for internal improvements. The parameter is intended primarily for use with custom models that have been upgraded for a new base model. The default value depends on whether the parameter is used with or without a custom model. See [Making speech recognition requests with upgraded custom models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-custom-u pgrade-use#custom-upgrade-use-recognition).
i_customization_weight	If you specify the customization ID (GUID) of a custom language model with the recognition request, the customization weight tells the service how much weight to give to words from the custom language model compared to those from the base model for the current request. Specify a value between 0.0 and 1.0. Unless a different customization weight was specified for the custom model when the model was trained, the default value is: * 0.3 for previous-generation models * 0.2 for most next-generation models * 0.1 for next-generation English and Japanese models A customization weight that you specify overrides a weight that was specified when the custom model was trained. The default value yields the best performance in general. Assign a higher value if your audio makes frequent use of OOV words from the custom model. Use caution when setting the weight: a higher value can improve the accuracy of phrases from the custom model's domain, but it can negatively affect performance on non-domain phrases. See [Using customization weight](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-language Use#weight).
i_inactivity_timeout	The time in seconds after which, if only silence (no speech) is detected in streaming audio, the connection is closed with a 400 error. The parameter is useful for stopping audio submission from a live microphone when a user simply walks away. Use `-1` for infinity. See [Inactivity timeout](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-input#t imeouts-inactivity).
i_keywords	An array of keyword strings to spot in the audio. Each keyword string can include one or more string tokens. Keywords are spotted only in the final results, not in interim hypotheses. If you specify any keywords, you must also specify a keywords threshold. Omit the parameter or specify an empty array if you do not need to spot keywords. You can spot a maximum of 1000 keywords with a single request. A single keyword can have a maximum length of 1024 characters, though the maximum effective length for double-byte languages might be shorter. Keywords are case-insensitive. See [Keyword spotting](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-spotti ng#keyword-spotting).
i_keywords_threshold	A confidence value that is the lower bound for spotting a keyword. A word is considered to match a keyword if its confidence is greater than or equal to the threshold. Specify a probability between 0.0 and 1.0. If you specify a threshold, you must also specify one or more keywords. The service performs no keyword spotting if you omit either parameter. See [Keyword spotting](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-spotti ng#keyword-spotting).
i_max_alternatives	The maximum number of alternative transcripts that the service is to return. By default, the service returns a single transcript. If you specify a value of `0`, the service uses the default value, `1`. See [Maximum alternatives](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-me tadata#max-alternatives).
i_word_alternatives_threshold	A confidence value that is the lower bound for identifying a hypothesis as a possible word alternative (also known as "Confusion Networks"). An alternative word is considered if its confidence is greater than or equal to the threshold. Specify a probability between 0.0 and 1.0. By default, the service computes no alternative words. See [Word alternatives](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-sp otting#word-alternatives).
i_word_confidence	If `true`, the service returns a confidence measure in the range of 0.0 to 1.0 for each word. By default, the service returns no word confidence scores. See [Word confidence](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-meta data#word-confidence).
i_timestamps	If `true`, the service returns time alignment for each word. By default, no timestamps are returned. See [Word timestamps](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-meta data#word-timestamps).
i_profanity_filter	If `true`, the service filters profanity from all output except for keyword results by replacing inappropriate words with a series of asterisks. Set the parameter to `false` to return results with no censoring. Note: The parameter can be used with US English and Japanese transcription only. See [Profanity filtering](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-forma tting#profanity-filtering).
i_smart_formatting	If `true`, the service converts dates, times, series of digits and numbers, phone numbers, currency values, and internet addresses into more readable, conventional representations in the final transcript of a recognition request. For US English, the service also converts certain keyword strings to punctuation symbols. By default, the service performs no smart formatting. Note: The parameter can be used with US English, Japanese, and Spanish (all dialects) transcription only. See [Smart formatting](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-form atting#smart-formatting).
i_speaker_labels	If `true`, the response includes labels that identify which words were spoken by which participants in a multi-person exchange. By default, the service returns no speaker labels. Setting `speaker_labels` to `true` forces the `timestamps` parameter to be `true`, regardless of whether you specify `false` for the parameter. * _For previous-generation models,_ the parameter can be used with Australian English, US English, German, Japanese, Korean, and Spanish (both broadband and narrowband models) and UK English (narrowband model) transcription only. * _For next-generation models,_ the parameter can be used with Czech, English (Australian, Indian, UK, and US), German, Japanese, Korean, and Spanish transcription only. See [Speaker labels](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-speaker- labels).
i_grammar_name	The name of a grammar that is to be used with the recognition request. If you specify a grammar, you must also use the `language_customization_id` parameter to specify the name of the custom language model for which the grammar is defined. The service recognizes only strings that are recognized by the specified grammar; it does not recognize other custom words from the model's words resource. See [Using a grammar for speech recognition](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-gra mmarUse).
i_redaction	If `true`, the service redacts, or masks, numeric data from final transcripts. The feature redacts any number that has three or more consecutive digits by replacing each digit with an `X` character. It is intended to redact sensitive numeric data, such as credit card numbers. By default, the service performs no redaction. When you enable redaction, the service automatically enables smart formatting, regardless of whether you explicitly disable that feature. To ensure maximum security, the service also disables keyword spotting (ignores the `keywords` and `keywords_threshold` parameters) and returns only a single final transcript (forces the `max_alternatives` parameter to be `1`). Note: The parameter can be used with US English, Japanese, and Korean transcription only. See [Numeric redaction](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-forma tting#numeric-redaction).
i_audio_metrics	If `true`, requests detailed information about the signal characteristics of the input audio. The service returns audio metrics with the final transcription results. By default, the service returns no audio metrics. See [Audio metrics](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-metrics #audio-metrics).
i_end_of_phrase_silence_time	Specifies the duration of the pause interval at which the service splits a transcript into multiple final results. If the service detects pauses or extended silence before it reaches the end of the audio stream, its response can include multiple final results. Silence indicates a point at which the speaker pauses between spoken words or phrases. Specify a value for the pause interval in the range of 0.0 to 120.0. * A value greater than 0 specifies the interval that the service is to use for speech recognition. * A value of 0 indicates that the service is to use the default interval. It is equivalent to omitting the parameter. The default pause interval for most languages is 0.8 seconds; the default for Chinese is 0.6 seconds. See [End of phrase silence time](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-parsing#si lence-time).
i_splt_trnscrpt_at_phrase_end	If `true`, directs the service to split the transcript into multiple final results based on semantic features of the input, for example, at the conclusion of meaningful phrases such as sentences. The service bases its understanding of semantic features on the base language model that you use with a request. Custom language models and grammars can also influence how and where the service splits a transcript. By default, the service splits transcripts based solely on the pause interval. If the parameters are used together on the same request, `end_of_phrase_silence_time` has precedence over `split_transcript_at_phrase_end`. See [Split transcript at phrase end](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-parsing#spl it-transcript).
i_speech_detector_sensitivity	The sensitivity of speech activity detection that the service is to perform. Use the parameter to suppress word insertions from music, coughing, and other non-speech events. The service biases the audio it passes for speech recognition by evaluating the input audio against prior models of speech and non-speech activity. Specify a value between 0.0 and 1.0: * 0.0 suppresses all audio (no speech is transcribed). * 0.5 (the default) provides a reasonable compromise for the level of sensitivity. * 1.0 suppresses no audio (speech detection sensitivity is disabled). The values increase on a monotonic curve. Specifying one or two decimal places of precision (for example, `0.55`) is typically more than sufficient. The parameter is supported with all next-generation models and with most previous-generation models. See [Speech detector sensitivity](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-det ection#detection-parameters-sensitivity) and [Language model support](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-detecti on#detection-support).
i_background_audio_suppression	The level to which the service is to suppress background audio based on its volume to prevent it from being transcribed as speech. Use the parameter to suppress side conversations or background noise. Specify a value in the range of 0.0 to 1.0: * 0.0 (the default) provides no suppression (background audio suppression is disabled). * 0.5 provides a reasonable level of audio suppression for general usage. * 1.0 suppresses all audio (no audio is transcribed). The values increase on a monotonic curve. Specifying one or two decimal places of precision (for example, `0.55`) is typically more than sufficient. The parameter is supported with all next-generation models and with most previous-generation models. See [Background audio suppression](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-det ection#detection-parameters-suppression) and [Language model support](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-detecti on#detection-support).
i_low_latency	If `true` for next-generation `Multimedia` and `Telephony` models that support low latency, directs the service to produce results even more quickly than it usually does. Next-generation models produce transcription results faster than previous-generation models. The `low_latency` parameter causes the models to produce results even more quickly, though the results might be less accurate when the parameter is used. The parameter is not available for previous-generation `Broadband` and `Narrowband` models. It is available for most next-generation models. * For a list of next-generation models that support low latency, see [Supported next-generation language models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-models-n g#models-ng-supported). * For more information about the `low_latency` parameter, see [Low latency](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-interim #low-latency).
i_character_insertion_bias	For next-generation models, an indication of whether the service is biased to recognize shorter or longer strings of characters when developing transcription hypotheses. By default, the service is optimized to produce the best balance of strings of different lengths. The default bias is 0.0. The allowable range of values is -1.0 to 1.0. * Negative values bias the service to favor hypotheses with shorter strings of characters. * Positive values bias the service to favor hypotheses with longer strings of characters. As the value approaches -1.0 or 1.0, the impact of the parameter becomes more pronounced. To determine the most effective value for your scenario, start by setting the value of the parameter to a small increment, such as -0.1, -0.05, 0.05, or 0.1, and assess how the value impacts the transcription results. Then experiment with different values as necessary, adjusting the value by small increments. The parameter is not available for previous-generation models. See [Character insertion bias](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-parsing#in sertion-bias).
e_response	Service return value of type T_SPEECH_RECOGNITION_RESULTS

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

register_callback
importing	i_callback_url	type string
	i_user_secret	type string optional
	i_accept	type string default 'application/json'
exporting	e_response	type t_register_status
raising	zcx_ibmc_service_exception

Registers a callback URL with the service for use with subsequent asynchronous recognition requests. The service attempts to register, or allowlist, the callback URL if it is not already registered by sending a `GET` request to the callback URL. The service passes a random alphanumeric challenge string via the `challenge_string` parameter of the request. The request includes an `Accept` header that specifies `text/plain` as the required response type.

To be registered successfully, the callback URL must respond to the `GET` request from the service. The response must send status code 200 and must include the challenge string in its body. Set the `Content-Type` response header to `text/plain`. Upon receiving this response, the service responds to the original registration request with response code 201.

The service sends only a single `GET` request to the callback URL. If the service does not receive a reply with a response code of 200 and a body that echoes the challenge string sent by the service within five seconds, it does not allowlist the URL; it instead sends status code 400 in response to the request to register a callback. If the requested callback URL is already allowlisted, the service responds to the initial registration request with response code 200.

If you specify a user secret with the request, the service uses it as a key to calculate an HMAC-SHA1 signature of the challenge string in its response to the `POST` request. It sends this signature in the `X-Callback-Signature` header of its `GET` request to the URL during registration. It also uses the secret to calculate a signature over the payload of every callback notification that uses the URL. The signature provides authentication and data integrity for HTTP communications.

After you successfully register a callback URL, you can use it with an indefinite number of recognition requests. You can register a maximum of 20 callback URLS in a one-hour span of time.

**See also:** [Registering a callback URL](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-async#regis ter).

Parameters

i_callback_url	An HTTP or HTTPS URL to which callback notifications are to be sent. To be allowlisted, the URL must successfully echo the challenge string during URL verification. During verification, the client can also check the signature that the service sends in the `X-Callback-Signature` header to verify the origin of the request.
i_user_secret	A user-specified string that the service uses to generate the HMAC-SHA1 signature that it sends via the `X-Callback-Signature` header. The service includes the header during URL verification and with every notification sent to the callback URL. It calculates the signature over the payload of the notification. If you omit the parameter, the service does not send the header.
e_response	Service return value of type T_REGISTER_STATUS

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

reset_acoustic_model
importing	i_customization_id	type string
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Reset a custom acoustic model

Resets a custom acoustic model by removing all audio resources from the model. Resetting a custom acoustic model initializes the model to its state when it was first created. Metadata such as the name and language of the model are preserved, but the model's audio resources are removed and must be re-created. The service cannot reset a model while it is handling another request for the model. The service cannot accept subsequent requests for the model until the existing reset request completes. You must use credentials for the instance of the service that owns a model to reset it.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**See also:** [Resetting a custom acoustic model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageAco usticModels#resetModel-acoustic).

Parameters

i_customization_id

The customization ID (GUID) of the custom acoustic model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

reset_language_model
importing	i_customization_id	type string
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Reset a custom language model

Resets a custom language model by removing all corpora, grammars, and words from the model. Resetting a custom language model initializes the model to its state when it was first created. Metadata such as the name and language of the model are preserved, but the model's words resource is removed and must be re-created. You must use credentials for the instance of the service that owns a model to reset it.

**See also:**
* [Resetting a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-manageLan guageModels#resetModel-language)
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)

Parameters

i_customization_id

The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

train_acoustic_model
importing	i_customization_id	type string
	i_custom_language_model_id	type string optional
	i_strict	type boolean default c_boolean_true
	i_accept	type string default 'application/json'
exporting	e_response	type t_training_response
raising	zcx_ibmc_service_exception

Train a custom acoustic model

Initiates the training of a custom acoustic model with new or changed audio resources. After adding or deleting audio resources for a custom acoustic model, use this method to begin the actual training of the model on the latest audio data. The custom acoustic model does not reflect its changed data until you train it. You must use credentials for the instance of the service that owns a model to train it.

The training method is asynchronous. Training time depends on the cumulative amount of audio data that the custom acoustic model contains and the current load on the service. When you train or retrain a model, the service uses all of the model's audio data in the training. Training a custom acoustic model takes approximately as long as the length of its cumulative audio data. For example, it takes approximately 2 hours to train a model that contains a total of 2 hours of audio. The method returns an HTTP 200 response code to indicate that the training process has begun.

You can monitor the status of the training by using the [Get a custom acoustic model](#getacousticmodel) method to poll the model's status. Use a loop to check the status once a minute. The method returns an `AcousticModel` object that includes `status` and `progress` fields. A status of `available` indicates that the custom model is trained and ready to use. The service cannot train a model while it is handling another request for the model. The service cannot accept subsequent training requests, or requests to add new audio resources, until the existing training request completes.

You can use the optional `custom_language_model_id` parameter to specify the GUID of a separately created custom language model that is to be used during training. Train with a custom language model if you have verbatim transcriptions of the audio files that you have added to the custom model or you have either corpora (text files) or a list of words that are relevant to the contents of the audio files. For training to succeed, both of the custom models must be based on the same version of the same base model, and the custom language model must be fully trained and available.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**See also:**
* [Train the custom acoustic model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-acoustic# trainModel-acoustic)
* [Using custom acoustic and custom language models together](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-useBot h#useBoth)

### Training failures

Training can fail to start for the following reasons:
* The service is currently handling another request for the custom model, such as another training request or a request to add audio resources to the model.
* The custom model contains less than 10 minutes of audio that includes speech, not silence.
* The custom model contains more than 50 hours of audio (for IBM Cloud) or more that 200 hours of audio (for IBM Cloud Pak for Data). **Note:** For IBM Cloud, the maximum hours of audio for a custom acoustic model was reduced from 200 to 50 hours in August and September 2022. For more information, see [Maximum hours of audio](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-audioReso urces#audioMaximum).
* You passed a custom language model with the `custom_language_model_id` query parameter that is not in the available state. A custom language model must be fully trained and available to be used to train a custom acoustic model.
* You passed an incompatible custom language model with the `custom_language_model_id` query parameter. Both custom models must be based on the same version of the same base model.
* The custom model contains one or more invalid audio resources. You can correct the invalid audio resources or set the `strict` parameter to `false` to exclude the invalid resources from the training. The model must contain at least one valid resource for training to succeed.

Parameters

i_customization_id	The customization ID (GUID) of the custom acoustic model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_custom_language_model_id	The customization ID (GUID) of a custom language model that is to be used during training of the custom acoustic model. Specify a custom language model that has been trained with verbatim transcriptions of the audio resources or that contains words that are relevant to the contents of the audio resources. The custom language model must be based on the same version of the same base model as the custom acoustic model, and the custom language model must be fully trained and available. The credentials specified with the request must own both custom models.
i_strict	If `false`, allows training of the custom acoustic model to proceed as long as the model contains at least one valid audio resource. The method returns an array of `TrainingWarning` objects that lists any invalid resources. By default (`true`), training of a custom acoustic model fails (status code 400) if the model contains one or more invalid audio resources.
e_response	Service return value of type T_TRAINING_RESPONSE

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

train_language_model
importing	i_customization_id	type string
	i_word_type_to_add	type string default 'all'
	i_customization_weight	type double optional
	i_strict	type boolean default c_boolean_true
	i_accept	type string default 'application/json'
exporting	e_response	type t_training_response
raising	zcx_ibmc_service_exception

Train a custom language model

Initiates the training of a custom language model with new resources such as corpora, grammars, and custom words. After adding, modifying, or deleting resources for a custom language model, use this method to begin the actual training of the model on the latest data. You can specify whether the custom language model is to be trained with all words from its words resource or only with words that were added or modified by the user directly. You must use credentials for the instance of the service that owns a model to train it.

The training method is asynchronous. It can take on the order of minutes to complete depending on the amount of data on which the service is being trained and the current load on the service. The method returns an HTTP 200 response code to indicate that the training process has begun.

You can monitor the status of the training by using the [Get a custom language model](#getlanguagemodel) method to poll the model's status. Use a loop to check the status every 10 seconds. If you added custom words directly to a custom model that is based on a next-generation model, allow for some minutes of extra training time for the model.

The method returns a `LanguageModel` object that includes `status` and `progress` fields. A status of `available` means that the custom model is trained and ready to use. The service cannot accept subsequent training requests or requests to add new resources until the existing request completes.

For custom models that are based on improved base language models, training also performs an automatic upgrade to a newer version of the base model. You do not need to use the [Upgrade a custom language model](#upgradelanguagemodel) method to perform the upgrade.

**See also:**
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)
* [Train the custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-languageC reate#trainModel-language)
* [Upgrading custom language models that are based on improved next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-custom-u pgrade#custom-upgrade-language-ng)

### Training failures

Training can fail to start for the following reasons:
* The service is currently handling another request for the custom model, such as another training request or a request to add a corpus or grammar to the model.
* No training data have been added to the custom model.
* The custom model contains one or more invalid corpora, grammars, or words (for example, a custom word has an invalid sounds-like pronunciation). You can correct the invalid resources or set the `strict` parameter to `false` to exclude the invalid resources from the training. The model must contain at least one valid resource for training to succeed.

Parameters

i_customization_id	The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_word_type_to_add	_For custom models that are based on previous-generation models_, the type of words from the custom language model's words resource on which to train the model: * `all` (the default) trains the model on all new words, regardless of whether they were extracted from corpora or grammars or were added or modified by the user. * `user` trains the model only on custom words that were added or modified by the user directly. The model is not trained on new words extracted from corpora or grammars. _For custom models that are based on next-generation models_, the service ignores the parameter. The words resource contains only custom words that the user adds or modifies directly, so the parameter is unnecessary.
i_customization_weight	Specifies a customization weight for the custom language model. The customization weight tells the service how much weight to give to words from the custom language model compared to those from the base model for speech recognition. Specify a value between 0.0 and 1.0. The default value is: * 0.3 for previous-generation models * 0.2 for most next-generation models * 0.1 for next-generation English and Japanese models The default value yields the best performance in general. Assign a higher value if your audio makes frequent use of OOV words from the custom model. Use caution when setting the weight: a higher value can improve the accuracy of phrases from the custom model's domain, but it can negatively affect performance on non-domain phrases. The value that you assign is used for all recognition requests that use the model. You can override it for any recognition request by specifying a customization weight for that request. See [Using customization weight](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-language Use#weight).
i_strict	If `false`, allows training of the custom language model to proceed as long as the model contains at least one valid resource. The method returns an array of `TrainingWarning` objects that lists any invalid resources. By default (`true`), training of a custom language model fails (status code 400) if the model contains one or more invalid resources (corpus files, grammar files, or custom words).
e_response	Service return value of type T_TRAINING_RESPONSE

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

unregister_callback
importing	i_callback_url	type string
raising	zcx_ibmc_service_exception

Unregister a callback

Unregisters a callback URL that was previously allowlisted with a [Register a callback](#registercallback) request for use with the asynchronous interface. Once unregistered, the URL can no longer be used with asynchronous recognition requests.

**See also:** [Unregistering a callback URL](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-async#unreg ister).

Parameters

i_callback_url

The callback URL that is to be unregistered.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

upgrade_acoustic_model
importing	i_customization_id	type string
	i_custom_language_model_id	type string optional
	i_force	type boolean default c_boolean_false
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Upgrade a custom acoustic model

Initiates the upgrade of a custom acoustic model to the latest version of its base language model. The upgrade method is asynchronous. It can take on the order of minutes or hours to complete depending on the amount of data in the custom model and the current load on the service; typically, upgrade takes approximately twice the length of the total audio contained in the custom model. A custom model must be in the `ready` or `available` state to be upgraded. You must use credentials for the instance of the service that owns a model to upgrade it.

The method returns an HTTP 200 response code to indicate that the upgrade process has begun successfully. You can monitor the status of the upgrade by using the [Get a custom acoustic model](#getacousticmodel) method to poll the model's status. The method returns an `AcousticModel` object that includes `status` and `progress` fields. Use a loop to check the status once a minute.

While it is being upgraded, the custom model has the status `upgrading`. When the upgrade is complete, the model resumes the status that it had prior to upgrade. The service cannot upgrade a model while it is handling another request for the model. The service cannot accept subsequent requests for the model until the existing upgrade request completes.

If the custom acoustic model was trained with a separately created custom language model, you must use the `custom_language_model_id` parameter to specify the GUID of that custom language model. The custom language model must be upgraded before the custom acoustic model can be upgraded. Omit the parameter if the custom acoustic model was not trained with a custom language model.

**Note:** Acoustic model customization is supported only for use with previous-generation models. It is not supported for next-generation models.

**See also:** [Upgrading a custom acoustic model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-custom-up grade#custom-upgrade-acoustic).

Parameters

i_customization_id	The customization ID (GUID) of the custom acoustic model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.
i_custom_language_model_id	If the custom acoustic model was trained with a custom language model, the customization ID (GUID) of that custom language model. The custom language model must be upgraded before the custom acoustic model can be upgraded. The custom language model must be fully trained and available. The credentials specified with the request must own both custom models.
i_force	If `true`, forces the upgrade of a custom acoustic model for which no input data has been modified since it was last trained. Use this parameter only to force the upgrade of a custom acoustic model that is trained with a custom language model, and only if you receive a 400 response code and the message `No input data modified since last training`. See [Upgrading a custom acoustic model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-custom-up grade#custom-upgrade-acoustic).

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.

public instance

upgrade_language_model
importing	i_customization_id	type string
	i_accept	type string default 'application/json'
raising	zcx_ibmc_service_exception

Upgrade a custom language model

Initiates the upgrade of a custom language model to the latest version of its base language model. The upgrade method is asynchronous. It can take on the order of minutes to complete depending on the amount of data in the custom model and the current load on the service. A custom model must be in the `ready` or `available` state to be upgraded. You must use credentials for the instance of the service that owns a model to upgrade it.

The method returns an HTTP 200 response code to indicate that the upgrade process has begun successfully. You can monitor the status of the upgrade by using the [Get a custom language model](#getlanguagemodel) method to poll the model's status. The method returns a `LanguageModel` object that includes `status` and `progress` fields. Use a loop to check the status every 10 seconds.

While it is being upgraded, the custom model has the status `upgrading`. When the upgrade is complete, the model resumes the status that it had prior to upgrade. The service cannot accept subsequent requests for the model until the upgrade completes.

For custom models that are based on improved base language models, the [Train a custom language model](#trainlanguagemodel) method also performs an automatic upgrade to a newer version of the base model. You do not need to use the upgrade method.

**See also:**
* [Language support for customization](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-c ustom-support)
* [Upgrading a custom language model](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-custom-up grade#custom-upgrade-language)
* [Upgrading custom language models that are based on improved next-generation models](https://cloud.ibm.com/docs/speech-to-text?topic=speech-to-text-custom-u pgrade#custom-upgrade-language-ng)

Parameters

i_customization_id

The customization ID (GUID) of the custom language model that is to be used for the request. You must make the request with credentials for the instance of the service that owns the custom model.

Class-based Exceptions

zcx_ibmc_service_exception

Exception being raised in case of an error.