trtc.on(TRTC.EVENT.CUSTOM_MESSAGE, event => { // Receive custom messages.
   // event.userId: The userId of the ASR robot.
   // event.cmdId: The message ID, which is fixed at 1 for transcriptions and captions.
   // event.seq: The sequence number of a message.
   // event.data: ArrayBuffer type. For content of transcriptions or captions, see the explanation of the data field below.
   const data = new TextDecoder().decode(event.data)
   // Explanation of the data field is as follows.
   console.log(`received custom msg from ${event.userId}, message: ${ data }`)
})

{
  "type": 10000,
  "sender": "user_a",
  "payload": {
     "text":"",
     "start_time":"00:00:02",
     "end_time":"00:00:05",
     "end": true
  }
}

{
  "type": 10000,
  "sender": "ai_951073",
  "payload": {
    "start_time_ms": 1760,
    "end_time_ms": 5530,
    "end": false,
    "roundid": "e6330a3c-eed7-40bb-8229-9bbe733a313f", // Unique ID for each conversation round
    "translation_text": "simultaneous interpretation of the meeting", // Translated text
    "translation_language": "en",   // Language code of the translation
    "taskid": "x-dPLCz" // Unique identifier of the transcription task
  }
}