Paraformer non-real-time speech recognition Android SDK

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Getting started

1. Obtain an API key: Obtain and configure an API key. For security, configure the API key as an environment variable.
   You can use a temporary API key to grant temporary access permissions or to strictly control risky operations, such as accessing or deleting sensitive data. A temporary API key is valid for 60 seconds by default and must be retrieved again after it expires.
2. Download the SDK and run the sample code:
   • Download the latest SDK package.
   • Unzip the package. In the app/libs directory, find the SDK in AAR format and add it to your project dependencies.For Android C++ integration, use the android_libs and android_include directories in the ZIP package to obtain the dynamic libraries and header files.
   • Open the project in Android Studio. The sample code is located in DashParaformerFileTranscriberActivity.java. Replace the API key and test the feature.

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Invocation steps

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Request parameters

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Connection and control parameters

• Example: The following JSON string is an example that does not list all available parameters. Add parameters as needed.

{
    "url": "wss://dashscope.aliyuncs.com/api-ws/v1/inference",
    "apikey": "st-****",
    "device_id": "my_device_id",
    "service_mode": "1"
}

• Parameter descriptions

  Parameter	Type	Required	Description
  url	String	Yes	The endpoint. This is fixed at wss://dashscope.aliyuncs.com/api-ws/v1/inference.
  apikey	String	Yes	The API key. Use a more secure temporary API key with a short validity period to reduce the risk of leaking a long-term key.
  service_mode	String	Yes	The operating mode. For non-real-time speech recognition, this is fixed at "1".
  device_id	String	Yes	A unique string that identifies the end user. You can set this to an in-app user ID or a unique device identifier generated by the client. This ID is mainly used for log tracking and troubleshooting.
  debug_path	String	No	The storage path for log files. This parameter is effective only if you set save_log to true when you call the initialize interface. In this case, you must specify a log file path. Otherwise, an error occurs. A maximum of two log files are kept locally.
  max_log_file_size	int	No	Sets the maximum size of a log file in bytes. This parameter is effective only if you set save_log to true when you call the initialize interface. Default value: 104857600 (100 × 1024 × 1024 bytes, or 100 MiB).
  log_track_level	int	No	Controls the filtering level of log content sent externally through the log callback (onFileTransLogTrackCallback). Default value: 2. Valid values: 0: LOG_LEVEL_VERBOSE 1: LOG_LEVEL_DEBUG 2: LOG_LEVEL_INFO 3: LOG_LEVEL_WARNING 4: LOG_LEVEL_ERROR 5: LOG_LEVEL_NONE (disables this feature) Note: log_track_level and level (set through the initialize interface) together determine which logs are sent to the callback. A log's level value must be greater than or equal to both the log_track_level and level values to trigger the callback. For example, if you set log_track_level to 2 (INFO) and level to 3 (WARNING), only logs at the WARNING level or higher (value >= 3) trigger the callback.

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Speech recognition effect parameters

• Example: The following JSON string is an example that does not list all available parameters. Add parameters as needed.

{
    "file_urls": [
        "{YOUR_AUDIO_URL}"
    ],
    "async_request": false,
    "nls_config": {
        "model":"paraformer-v2",
        "disfluency_removal_enabled":false,
        "timestamp_alignment_enabled": false
    }
}

• Parameter descriptions

  Parameter	Type	Required	Description
  file_urls	array[string]	Yes	A list of URLs for the audio or video files to transcribe. The HTTP and HTTPS protocols are supported. A single request supports only 1 URL.If audio files are stored in Alibaba Cloud OSS, the SDK does not support temporary URLs with the oss:// prefix. Audio formats: aac, amr, avi, flac, flv, m4a, mkv, mov, mp3, mp4, mpeg, ogg, opus, wav, webm, wma, wmv Because of the many audio and video formats and their variations, it is not technically possible to test all of them. The API cannot guarantee that all formats are recognized correctly. Test your files to verify that you get normal speech recognition results. Audio sampling rate Varies by model: paraformer-v2 supports any sample rate. paraformer-8k-v2 supports only the 8 kHz sample rate. Audio file size and duration: The audio file cannot exceed 2 GB. The duration must be within 12 hours. If you want to process a file that exceeds these limits, you can pre-process the file to reduce its size. For best practices on file pre-processing, see Pre-process video files to improve transcription efficiency (for audio file recognition scenarios).
  async_request	boolean	No	Specifies whether the speech recognition is an asynchronous request.Default value: false.Valid values: true: asynchronous request false: synchronous request
  apikey	string	No	If the apikey in the Connection and control parameters is a temporary API key, you can update it here to prevent it from expiring.
  nls_config	object	Yes	The core configuration object for speech recognition. It includes key parameters such as model selection and recognition effect control.
  nls_config.model	string	Yes	The speech recognition model.
  nls_config.language_hints	array[string]	No	Specifies the language codes of the speech to be recognized. This parameter applies only to the paraformer-v2 model.Default value: ["zh", "en"].Supported language codes: zh: Chinese en: English ja: Japanese yue: Cantonese ko: Korean de: German fr: French ru: Russian
  nls_config.disfluency_removal_enabled	boolean	No	Specifies whether to filter disfluent words, such as "um" and "ah".Default value: false.Valid values: true: filter false: do not filter
  nls_config.timestamp_alignment_enabled	boolean	No	Specifies whether to enable the timestamp alignment feature.Default value: false.Valid values: true: enable false: disable
  nls_config.special_word_filter	object	No	Specifies the sensitive words to process during speech recognition and supports different processing methods for different sensitive words.If this parameter is not passed, the system enables the built-in sensitive word filtering logic. Words in the recognition result that match the Alibaba Cloud Model Studio sensitive word list are replaced with an equal number of asterisks (*).If you pass this parameter, you can implement the following sensitive word processing policies: Replace with *: Replaces matching sensitive words with an equal number of asterisks (*). Direct filtering: Removes matching sensitive words from the recognition result completely. The value of this parameter should be a JSON object with the following structure: Copy { "filter_with_signed": { "word_list": ["test"] }, "filter_with_empty": { "word_list": ["start", "happen"] }, "system_reserved_filter": true } JSON field descriptions: filter_with_signed Type: object. Required: No. Description: Configures the list of sensitive words to be replaced with *. Matching words in the recognition result are replaced with an equal number of asterisks (*). Example: Using the JSON above, the speech recognition result for "Help me test this piece of code" will be "Help me **** this piece of code". Internal fields: word_list: A string array that lists the sensitive words to be replaced. filter_with_empty Type: object. Required: No. Description: Configures the list of sensitive words to be removed (filtered) from the recognition result. Matching words in the recognition result are completely deleted. Example: Using the JSON above, the speech recognition result for "Is the game about to start?" will be "Is the game about to?". Internal fields: word_list: A string array that lists the sensitive words to be completely removed (filtered). system_reserved_filter Type: Boolean value. Required: No. Default value: true. Description: Specifies whether to enable the system's preset sensitive word rules. If set to true, the system's built-in sensitive word filtering logic is also enabled. Words in the recognition result that match the Alibaba Cloud Model Studio sensitive word list are replaced with an equal number of asterisks (*).
  nls_config.channel_id	array[integer]	No	Specifies the audio track indexes to recognize in a multi-track audio file. Indexes start from 0. For example, [0] means recognizing the first track, and [0, 1] means recognizing both the first and second tracks simultaneously. If this parameter is omitted, only the first track is processed by default. Each specified track is billed independently. For example, requesting [0, 1] for a single file incurs two separate charges. Default value: [0]
  nls_config.diarization_enabled	boolean	No	Automatic speaker diarization. Disabled by default.Only applicable to mono audio. Multi-channel audio does not support speaker diarization.When this feature is enabled, the recognition results will include a speaker_id field to distinguish different speakers. If speaker diarization is enabled, it is recommended that the audio duration does not exceed 2 hours, otherwise recognition may fail or time out. For an example of speaker_id, see Recognition result description.
  nls_config.speaker_count	integer	No	A reference value for the number of speakers. To use this feature, set diarization_enabled to true.By default, the number of speakers is automatically determined. If you configure this parameter, it only helps the algorithm try to output the specified number of speakers. It does not guarantee that the exact number will be output.Value range: [2, 100]. This feature is used to distinguish multiple speakers, so you must set it to at least 2.
  nls_config.vocabulary_id	string	No	The ID of the hotword vocabulary, used to improve the recognition accuracy of specific words. This parameter applies to v2 and later models. For information on how to use hotwords, see Customize hotwords.

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Key interfaces

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NativeNui

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initialize

• Method signature

public synchronized int initialize(final INativeFileTransCallback callback,
                                   String parameters,
                                   final Constants.LogLevel level,
                                   final boolean save_log)

• Parameter descriptions

  Parameter	Type	Description
  callback	INativeFileTransCallback	The implementation of the event and data callback interface.
  parameters	String	A JSON string that contains authentication, connection, and debugging parameters. See Connection and control parameters.
  level	Constants.LogLevel	Controls the logging level of the SDK itself.
  save_log	boolean	Specifies whether to save binary logs. If true, you must specify a path using debug_path in the Connection and control parameters. You can also set the file size using max_log_file_size.

• Return value description

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setParams

• Method signature

public synchronized int setParams(String params);

• Parameter descriptions

  Parameter	Type	Description
  params	String	The nls_config parameter from Speech recognition effect parameters. Parameters other than nls_config cannot be set using this method.Example: Copy { "nls_config": { "model":"paraformer-v2", "disfluency_removal_enabled":false, "timestamp_alignment_enabled": false } }

• Return value description

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startFileTranscriber

• Method signature

public synchronized int startFileTranscriber(String params, byte[] task_id)

• Parameter descriptions

  Parameter	Type	Description
  params	String	Speech recognition effect parameters.Example: Copy { "file_urls": [ "{YOUR_AUDIO_URL}" ], "async_request": false, "nls_config": { "model":"paraformer-v2", "disfluency_removal_enabled":false, "timestamp_alignment_enabled": false } }
  task_id	byte[]	The task ID. The SDK internally generates a random string. You can get the task_id after this method is called successfully.

• Return value description

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queryFileTranscriber

• Method signature

public synchronized int queryFileTranscriber(String task_id)

• Parameter descriptions

  Parameter	Type	Description
  task_id	byte[]	The ID of the task to query.

• Return value description

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cancelFileTranscriber

• Method signature

public synchronized int cancelFileTranscriber(String task_id)

• Parameter descriptions

  Parameter	Type	Description
  task_id	byte[]	The ID of the task to cancel.

• Return value description

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release

• Method signature

public synchronized int release();

• Return value description

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GetVersion

• Method signature

public synchronized String GetVersion();

• Return value description The current SDK version information.

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INativeFileTransCallback: Listener callback

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onFileTransEventCallback: Listen for events and speech recognition results

• Method signature

void onFileTransEventCallback(NuiEvent event, final int resultCode, final int arg2, AsrResult asrResult, String taskId);

• Parameter descriptions

  Parameter	Type	Description
  event	NuiEvent	The callback event.
  resultCode	int	Valid only when the EVENT_ASR_ERROR event occurs.
  asrResult	AsrResult	The speech recognition result.
  taskId	String	The task ID.
  arg2	int	A reserved parameter.

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onFileTransLogTrackCallback: Listen for trace logs

default void onFileTransLogTrackCallback(Constants.LogLevel level, String log)

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NuiEvent: Event types