7.3 Audio Playback Section

7.3.1 Overview

The A2 Lite robot does not have a microphone and thus cannot perform voice interaction functions. However, it is equipped with a speaker that can play basic audio files and adjust volume. It also supports queue playback, playback status queries, and interruption control logic.

7.3.2 Audio File Playback RPC Interface

Interface Name	`pb:/aimdk.protocol.TTSService/PlayMediaFile`
Function Summary	Audio file playback
Interface Type	HTTP JSON RPC
URL	http://127.0.0.1:59201/rpc/aimdk.protocol.TTSService/PlayMediaFile
Input Parameters	text `{ "file_name": "wake.pcm", "priority_level": "INTERACTION_L6", "domain": "example", "trace_id": "hafhjkqwjwefk", "is_interrupted": true }` file_name: File name (stored in `/agibot/data/var/interaction/audio/`, for example, wake.pcm. The file should be a 24kHz, 16-bit, mono PCM file. A separate folder needs to be created, and the input should be in the format of folder name/file name, such as file/wake.pcm) priority_level: Priority level, keep INTERACTION_L6 domain: Caller source identifier, you can pass in a custom client string for easier troubleshooting, etc. trace_id: Playback ID, if you need to get the playback status, you need to pass this field and use its value as the parameter to query the playback status is_interrupted: Whether to interrupt playback of the same priority, please default to true. For queue playback requirements, you can use false
Output Parameters	text `{ "text": "wake.pcm", "priority_level": "INTERACTION_L6", "priority_weight": 0, "domain": "example", "trace_id": "hafhjkqwjwefk", "is_sucess": true, "error_message": "", "estimated_duration": 0 }` text: File name priority_level: Priority level, no need to pay attention pritority_weight: Priority weight, no need to pay attention domain: Caller source identifier, returns the custom string passed in the request for easier troubleshooting trace_id: Playback ID, returns the custom string passed in the request for easier troubleshooting is_success: Whether the priority check was successful, generally true, but it does not mean it will play. For example, passing an incorrect or non-existent file name will still return true. Only when there is a higher-priority content being played, such as a fault alarm, will it return true estimated_duration: Invalid field, no need to pay attention, unable to estimate playback duration
Example Script	examples/audio/play_media_file.sh
Notes	Supports standard 44-byte header Linear PCM wav files. Other header formats and compressed formats are not supported. It is recommended to use 24kHz, 16-bit, mono PCM files If an incorrect or non-existent file name is passed, it will silently fail without playing, and is_success will return true

7.3.3 Audio File Playback Status Query RPC Interface

Interface Name	`pb:/aimdk.protocol.TTSService/GetAudioStatus`
Function Summary	Audio file playback status query
Interface Type	HTTP JSON RPC
URL	http://127.0.0.1:59201/rpc/aimdk.protocol.TTSService/GetAudioStatus
Input Parameters	text `{ "trace_id": "hafhjkqwjwefk" }` trace_id: Playback ID, fill in the custom ID passed when calling the PlayMediaFile interface
Output Parameters	text `{ "tts_status": { "text": "", "priority": 0, "trace_id": "", "tts_status": "TTSStatusType_Playing", "domain": "", "error_message": "" } }` tts_status: Playback status, enumeration values TTSConfigStatusType_Unknown: Unknown status TTSStatusType_Begin: Start playback, brief, usually not queried TTSStatusType_Playing: Playing TTSStatusType_End: End of playback, brief, usually not queried TTSStatusType_Stop: Pause playback/cancel playback/interrupt playback TTSStatusType_Error: Playback failed TTSStatusType_InQue: In the playback queue, not yet started TTSStatusType_NOTInQue: No such text in the playback queue, not playing, enters this state after playback ends The rest of the fields are invalid and do not need to be paid attention to
Example Script	examples/audio/get_audio_status.sh
Notes	A successful playback queried through this RPC interface generally returns InQue, Playing, and NOTInQue states

7.3.4 Audio File Playback Interruption RPC Interface

We provide interfaces for interrupting a single file playback and clearing the entire playback queue.

Interface Name	`pb:/aimdk.protocol.TTSService/StopTTSTraceId`
Function Summary	Interrupt a single file playback
Interface Type	HTTP JSON RPC
URL	http://127.0.0.1:59201/rpc/aimdk.protocol.TTSService/StopTTSTraceId
Input Parameters	text `{ "trace_id": "hafhjkqwjwefk" }` trace_id: Playback ID, fill in the custom ID passed when calling the PlayMediaFile interface
Output Parameters	text `{ "state":"CommonState_UNKNOWN" }` state: Request status, no need to pay attention to the specific value, HTTP request returning 200 indicates success
Example Script	examples/audio/stop_trace_id.sh
Notes

Interface Name	`pb:/aimdk.protocol.TTSService/StopTTS`
Function Summary	Terminate all audio file playback, including the current playback task and all tasks in the queue
Interface Type	HTTP JSON RPC
URL	http://127.0.0.1:59201/rpc/aimdk.protocol.TTSService/StopTTS
Input Parameters	text `{}` trace_id: Playback ID, fill in the custom ID passed when calling the PlayMediaFile interface
Output Parameters	text `{ "state":"CommonState_UNKNOWN" }` state: Request status, no need to pay attention to the specific value, HTTP request returning 200 indicates success
Example Script	examples/audio/stop_all.sh
Notes

7.3.5 Volume Get and Set RPC Interfaces

Interface Name	`pb:/aimdk.protocol.HalAudioService/GetAudioVolume`
Function Summary	Get the current volume level
Interface Type	HTTP JSON RPC
URL	http://127.0.0.1:59201/rpc/aimdk.protocol.HalAudioService/GetAudioVolume
Input Parameters	text `{}`
Output Parameters	text `{ "header": { "code": "0", "msg": "GetAudioVolume successfully", "trace_id": "", "domin": "" }, "audio_volume": 80, "is_mute": false }` audio_volume: Volume level, a value between 0-100 is_mute: Whether muted
Example Script	examples/audio/get_audio_volume.sh
Notes

Interface Name	`pb:/aimdk.protocol.HalAudioService/SetAudioVolume`
Function Summary	Adjust the volume
Interface Type	HTTP JSON RPC
URL	http://127.0.0.1:59201/rpc/aimdk.protocol.HalAudioService/SetAudioVolume
Input Parameters	text `{ "audio_volume": 70, "is_mute": false }` audio_volume: Volume level, a value between 0-100. Note: Do not set the volume above 70, as exceeding this range will cause the speaker to exceed its rated operating capacity, leading to damage is_mute: Whether muted
Output Parameters	text `{ "header": { "code": "0", "msg": "SetAudioVolume successfully", "trace_id": "", "domin": "" }, "pkg_name": "", "is_success": false }` pkg_name: Invalid field, no need to pay attention is_success: Invalid field, no need to pay attention
Example Script	examples/audio/set_audio_volume.sh
Notes