time audio and video translation - Qwen-Livetranslate-Realtime-Client events

This topic describes the client events for the qwen3-livetranslate-flash-realtime API.

Reference: Real-time audio and video translation - Qwen.

session.update

Send this event after establishing a WebSocket connection to update the default session configuration. The server validates parameters and returns either an error (if invalid) or the updated configuration (if valid). type *string* (Required) Event type. Must be set to session.update.

{
 "event_id": "event_ToPZqeobitzUJnt3QqtWg",
 "type": "session.update",
 "session": {
 "modalities": \[
 "text",
 "audio"
 \],
 "voice": "Cherry",
 "input_audio_format": "pcm16",
 "output_audio_format": "pcm24",
 "input_audio_transcription": {
 "model": "qwen3-asr-flash-realtime",
 "language": "zh"
 },
 "translation": {
 "language": "en"
 }
 }
}

      **session **`*object*`* *(Optional) The session configuration.

Properties

**modalities **array* *(Optional) Output modalities. Valid values:

• ["text"] Outputs text only.
• ["text","audio"] (Default) Outputs text and audio.

**voice **string* *(Optional) Voice for generated audio. Valid values: Supported voices. Default value: Cherry.

**input_audio_transcription **object* *(Optional) Configuration for input audio. Properties

**model **string* *(Optional) Speech recognition model. If configured, the server returns both the recognition result (original source language text) and translation via the conversation.item.input_audio_transcription.text and conversation.item.input_audio_transcription.completed events. Valid value: qwen3-asr-flash-realtime.

**language **string* *(Optional) Source language for translation. Valid values: Supported languages. Default value: en.

**input_audio_format **string* *(Optional) Input audio format. Currently, this parameter can only be set to pcm16.

**output_audio_format **string* *(Optional) Output audio format. Currently, this parameter can only be set to pcm24.

**translation **object* *(Optional) Translation configuration. Properties

**language **string* *(Optional) Target language for translation. Valid values: Supported languages. Default value: en.

input_audio_buffer.append

Appends audio bytes to the input audio buffer. The service uses this buffer to detect speech and determine when to submit it. type *string* (Required) Event type. Must be set to input_audio_buffer.append.

{
 "event_id": "event_xxx",
 "type": "input_audio_buffer.append",
 "audio": "xxx"
}

     **audio **`*string*`** (Required)** Base64-encoded audio data.

input_image_buffer.append

Adds image data to the image buffer from a local file or real-time video stream.

Image input limits:

• Image format: JPG or JPEG. Recommended resolution for optimal performance: 480p or 720p (maximum: 1080p).

• Maximum image size: 500 KB (before Base64 encoding).

• Image data must be Base64-encoded.

• Maximum frequency: 2 images per second.

• Send at least one input_audio_buffer.append event before sending input_image_buffer.append.

  type *string* (Required) Event type. Must be set to input_image_buffer.append.

{
 "event_id": "event_xxx",
 "type": "input_image_buffer.append",
 "image": "xxx"
}

     **image **`*string*`* *** (Required)** Base64-encoded image data.

session.finish

Send this event to end the current session. Server responses:

• If speech is detected: Server completes speech recognition, sends conversation.item.input_audio_transcription.completed with the recognition result, then sends session.finished to indicate session end.

• If no speech is detected: Server sends session.finished directly.

The client must disconnect after receiving session.finished. *type *string* *** (Required) Event type. Must be set to session.finish.

{
 "event_id": "event_xxx",
 "type": "session.finish"
}