This guide shows you how to use the Qwen-Audio-3.1-ASR-Flash-Message real-time speech recognition iOS SDK to transcribe speech into text.
Quick start
-
Get an API key: Obtain an API key
-
Download the SDK and run the sample code:
- Download the latest SDK package.
- Extract the ZIP package and add the included nuisdk.xcframework to your project.
- In Build Phases → Link Binary With Libraries, add nuisdk.xcframework.
- In General → Frameworks, Libraries, and Embedded Content, set nuisdk.xcframework to Embed & Sign.
- Open the sample project in Xcode. The sample code is in
DashFunAsrSpeechTranscriberViewController.m. Replace the API key with your own to try out the feature.
Call sequence
- Initialize the SDK.
- Set parameters for your use case: use the nui_initialize API to set Connection and control parameters, and use the nui_set_params API to set Recognition quality parameters.
- Call nui_dialog_start to start the recognition process.
- In the onNuiAudioStateChanged callback, open the recording device based on the audio state.
- In the onNuiNeedAudioData callback, continuously supply recording data, or call nui_update_audio_data to actively push recording data.
- In the onNuiEventCallback callback, listen for events and retrieve speech recognition results.
- Call nui_dialog_cancel to stop recognition, and confirm that recognition has finished by listening for the EVENT_TRANSCRIBER_COMPLETE event.
- When you no longer need the recognition feature, call nui_release to release the SDK resources.
Request parameters
Connection and control parameters
Configure these parameters by passing a JSON string in the parameters argument of the nui_initialize API.
Example parameters: The following JSON string is an example and does not list all parameters. Add the parameters you need when you write your code:
{
"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 | Service address:
Replace |
apikey | String | Yes | API key. |
service_mode | String | Yes | Run mode. Fixed to "1" for real-time speech recognition. |
device_id | String | Yes | A unique string that identifies the end user. You can set it to an in-app user ID or a device identifier generated on the client. This ID is used mainly for log tracing and troubleshooting. |
audio_update_manually | String | No | Whether to enable active audio data pushing. Default: If set to |
workspace | String | No | The path where on-device resource files are stored. This parameter is required when audio_update_manually is set to "true" and an on-device audio processing capability such as AEC or VAD is enabled. |
debug_path | String | No | Storage path for the log file. This parameter takes effect only when At most two log files are kept locally. |
save_wav | String | No | Whether to save an audio file for debugging. The audio file is saved under Default: "false". Valid values:
This parameter takes effect only when |
max_log_file_size | int | No | Maximum size of the log file, in bytes. This parameter takes effect only when Default: 104857600 (100 * 1024 * 1024 bytes, that is, 100 MiB). |
log_track_level | int | No | Filter level for the log content sent through the log callback (onNuiLogTrackCallback). Default: 2. Valid values:
Note: |
Recognition quality parameters
Configure these parameters by passing a JSON string in the params argument of the nui_set_params API.
Example parameters: The following JSON string is an example and does not list all parameters. Add the parameters you need when you write your code:
{
"service_type": 4,
"nls_config": {
"model": "qwen-audio-3.1-asr-flash-message",
"sr_format": "pcm",
"sample_rate": "16000"
}
}
Parameter descriptions
| Top-level parameter | Type | Required | Description |
|---|---|---|---|
service_type | int | Yes | Speech service type. Fixed to 4 for real-time speech recognition. |
nls_config | object | Yes | The core recognition configuration object. It contains key parameters such as model selection and recognition quality controls. |
nls_config.model | string | Yes | The model name. Set to qwen-audio-3.1-asr-flash-message. |
nls_config.sr_format | string | Yes | The audio format. Valid values:
ImportantIf you provide PCM audio data and set this parameter to |
nls_config.sample_rate | int | Yes | The sample rate, in Hz. Only |
nls_config.max_sentence_silence | int | No | The VAD silence threshold for segmentation, in ms. When the silence after a segment of speech exceeds this threshold, the system determines that the sentence has ended. Default value: 1300. Valid values: [200, 6000]. |
nls_config.heartbeat | boolean | No | Whether to enable heartbeat packets. Default value: false.
Silent audio refers to content in an audio file or data stream that contains no sound signal. You can generate silent audio in several ways, such as using audio editing software like Audacity or Adobe Audition, or using a command-line tool like FFmpeg. |
nls_config.disfluency_removal_enabled | boolean | No | Whether to filter filler words and polish the output. Defaults to false. Set to true to enable this feature. |
nls_config.intermediate_result_enabled | boolean | No | Whether to return intermediate streaming results. Defaults to false. Set to true to return intermediate streaming results. |
nls_config.vocabulary_id | string | No | The ID of a precompiled hot word list. Generate this ID in advance by calling the create hot word list API. Pass the ID during recognition to use the hot words in the list. Suitable for scenarios where the vocabulary is known and relatively stable, and where you need to reuse the same word list across requests. For usage details, see Precompiled hotwords. |
nls_config.instant_vocabulary | object | No | Instant hot words. Passed as key-value pairs, where the key is the hot word text ( Suitable for temporary, session-level hot word optimization. When instant and precompiled hotwords are configured together, the system merges both sets. If the merged set contains more than 2000 hotwords, the system randomly selects 2000 to use. For usage, supported models, and limits, see Instant hotwords. |
nls_config.speech_noise_threshold | float | No | The threshold for distinguishing speech from noise, used to adjust the sensitivity of Voice Activity Detection (VAD). Valid values: [-1.0, 1.0]. Value descriptions:
This is an advanced configuration parameter. Adjusting it can significantly affect recognition results. Recommendations:
|
nls_config.enable_connection_fast_check | BOOL | No | Whether to enable fast network checks so that disconnections can be reported as soon as possible. Default: NO. |
Key APIs
NeoNui
nui_initialize
Initializes the speech recognition SDK instance. The SDK is a singleton. Do not initialize it again before you call nui_release.
Method signature-(NuiResultCode) nui_initialize:(const char *)parameters
logLevel:(NuiSdkLogLevel)level
saveLog:(BOOL)save_log;
Parameter descriptions
| Parameter | Type | Description |
|---|---|---|
parameters | char* | A JSON string that contains authentication, connection, and debugging parameters. See Connection and control parameters. |
level | NuiSdkLogLevel | Print level for the SDK's own logs. |
save_log | BOOL | Whether to save logs locally. If set to YES, specify a path with debug_path in Connection and control parameters, and optionally set the file size with max_log_file_size. |
Returns an error code. See Error code reference.
nui_set_params
Sets the Recognition quality parameters in JSON format. Call this method before nui_dialog_start.
Method signature-(NuiResultCode) nui_set_params:(const char *)params;
Parameter descriptions
| Parameter | Type | Description |
|---|---|---|
params | char* | Recognition quality parameters. |
Returns an error code. See Error code reference.
nui_dialog_start
Starts recognition.
Method signature-(NuiResultCode) nui_dialog_start:(NuiVadMode)vad_mode
dialogParam:(const char *)dialog_params;
Parameter descriptions
| Parameter | Type | Description |
|---|---|---|
vad_mode | NuiVadMode | VAD mode. Fixed to MODE_P2T. |
dialog_params | char* | If the The content is in JSON format: |
Returns an error code. See Error code reference.
nui_dialog_cancel
Ends recognition or cancels the current interaction immediately.
Method signature-(NuiResultCode) nui_dialog_cancel:(BOOL)force;
Parameter descriptions
| Parameter | Type | Description |
|---|---|---|
force | BOOL | Whether to end forcibly and discard the final result.
|
Returns an error code. See Error code reference.
nui_dialog_action
Sends a dialog action during an interaction to update the recognition context or other runtime behavior.
Method signature-(NuiResultCode) nui_dialog_action:(const char *)action_params;
Parameter descriptions
| Parameter | Type | Description |
|---|---|---|
action_params | char* | A JSON string used to update the recognition context or other runtime behavior. |
action_params.type | String | Fixed to "action". |
action_params.command | String | Runtime command. Valid values:
|
action_params.context | String | When |
Returns an error code. See Error code reference.
nui_update_audio_data
When audio_update_manually is set to "true", recording data is no longer supplied through onNuiNeedAudioData. Use this method to actively push it instead.
-(NuiResultCode) nui_update_audio_data:(const char *)data
Len:(int)length
FirstPack:(BOOL)first_pack;
Parameter descriptions
| Parameter | Type | Description |
|---|---|---|
data | const char * | The audio data to push. |
length | int | The length of the audio data, in bytes. |
first_pack | BOOL | You do not need to use this parameter. |
Returns an error code. See Error code reference.
nui_push_reference_data
When audio_update_manually is set to "true" and on-device acoustic echo cancellation (AEC) is enabled, use this method to push the audio played by the player as the reference signal.
-(NuiResultCode) nui_push_reference_data:(const char *)data
Len:(int)length
FirstPack:(BOOL)first_pack;
Parameter descriptions
| Parameter | Type | Description |
|---|---|---|
data | const char * | The audio data to push. |
length | int | The length of the audio data, in bytes. |
first_pack | BOOL | You do not need to use this parameter. |
Returns an error code. See Error code reference.
nui_release
Releases all internal SDK resources and forcibly terminates all running tasks. After you call this method, the SDK instance becomes unavailable. To use it again, you must call nui_initialize to initialize it again.
Method signature-(NuiResultCode) nui_release;
Return value
Returns an error code. See Error code reference.
nui_get_version
Gets the current SDK version. This method returns a value only after nui_initialize is called.
-(const char*) nui_get_version;
Return value
The current SDK version.
nui_get_all_response
Gets the complete information for the current event callback.
Method signature-(const char*) nui_get_all_response;
Return value
The complete event information as a JSON string.
NeoNuiSdkDelegate: callback listeners
onNuiEventCallback: listen for events and speech recognition results
Method signature-(void) onNuiEventCallback:(NuiCallbackEvent)nuiEvent
dialog:(long)dialog
kwsResult:(const char *)wuw
asrResult:(const char *)asr_result
ifFinish:(BOOL)finish
retCode:(int)code;
Parameter descriptions
| Parameter | Type | Description |
|---|---|---|
nuiEvent | NuiCallbackEvent | Callback event. |
dialog | long | Session ID. You do not need to use this parameter. |
wuw | char* | Voice wake-up. You do not need to use this parameter. |
asr_result | char* | Speech recognition result. |
finish | BOOL | Whether the current recognition round has finished. |
code | int | Error code. Valid when the EVENT_ASR_ERROR event occurs. See Error code reference. |
onNuiAudioStateChanged: listen for the audio state
The SDK uses this callback to notify you when to start or stop recording.
Method signature-(void) onNuiAudioStateChanged:(NuiAudioState)state;
NuiAudioState states
| Parameter | Description |
|---|---|
STATE_OPEN | The interaction has started. You can open the recording device and start recording. |
STATE_PAUSE | The interaction has stopped. You can stop recording. |
STATE_CLOSE | The SDK instance has been released. You can close the recording device completely. |
onNuiNeedAudioData: supply audio data for recognition
After recognition starts, this callback is triggered continuously. Supply the audio data to be recognized in it.
Method signature-(int) onNuiNeedAudioData:(char *)audioData length:(int)len;
Parameter descriptions
| Parameter | Type | Description |
|---|---|---|
audioData | char * | The audio data to supply. |
len | int | The size of the supplied audio data, in bytes. |
onNuiAssistEventCallback: receive auxiliary data and information
Receives auxiliary events and related data from the SDK.
Method signature-(void) onNuiAssistEventCallback:(NuiCallbackEvent)nuiEvent
info:(char*)info
infoLen:(int)info_len
buffer:(char*)buffer
len:(int)len;
Parameter descriptions
| Parameter | Type | Description |
|---|---|---|
nuiEvent | NuiCallbackEvent | The callback event. |
info | char * | You do not need to use this parameter. |
info_len | int | You do not need to use this parameter. |
buffer | char * | Auxiliary data, such as audio data after AEC processing. |
len | int | The length of the auxiliary data, in bytes. |
onNuiLogTrackCallback: listen for tracking logs
This callback receives the SDK's detailed internal logs to help you locate and debug issues.
-(void) onNuiLogTrackCallback:(NuiSdkLogLevel)level
logMessage:(const char *)log;
NuiCallbackEvent: event types
| Event | Description |
|---|---|
| EVENT_TRANSCRIBER_STARTED | The task started successfully. |
| EVENT_VAD_START | Triggered right after the task starts. It does not mean that the start of speech has been detected. |
| EVENT_VAD_END | The end of speech was detected. |
| EVENT_ASR_PARTIAL_RESULT | An intermediate speech recognition result. |
| EVENT_ASR_ERROR | An error occurred during speech recognition. |
| EVENT_MIC_ERROR | Triggered because no audio data was received for 2 consecutive seconds. |
| EVENT_SENTENCE_END | The end of a sentence was detected. A complete recognition result for the sentence is returned. |
| EVENT_TRANSCRIBER_COMPLETE | Speech recognition finished. |
| EVENT_AEC_DATA | Audio data after acoustic echo cancellation (AEC) processing. |