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§5.1

Simulcast video tracks - 3 alternate video qualities along with audio

This example shows catalog for a media producer capable of sending 3 time-aligned video tracks for high definition, low definition and medium definition video qualities, along with an audio track.

{
  "version": "1",
  "generatedAt": 1746104606044,
  "tracks":[
    {
      "name": "hd",
      "renderGroup": 1,
      "packaging": "cmaf",
      "isLive": true,
      "targetLatency": 2000,
      "initRef": "init-hd",
      "role": "video",
      "codec":"avc1.640028",
      "width":1920,
      "height":1080,
      "bitrate":5000000,
      "framerate":30,
      "altGroup":1
    },
    {
      "name": "md",
      "renderGroup": 1,
      "packaging": "cmaf",
      "isLive": true,
      "targetLatency": 2000,
      "initRef": "init-md",
      "role": "video",
      "codec":"avc1.64001e",
      "width":720,
      "height":640,
      "bitrate":3000000,
      "framerate":30,
      "altGroup":1
    },
    {
      "name": "sd",
      "renderGroup": 1,
      "packaging": "cmaf",
      "isLive": true,
      "targetLatency": 2000,
      "initRef": "init-sd",
      "role": "video",
      "codec":"avc1.64000d",
      "width":192,
      "height":144,
      "bitrate":500000,
      "framerate":30,
      "altGroup":1
    },
    {
      "name": "audio",
      "renderGroup": 1,
      "packaging": "cmaf",
      "isLive": true,
      "targetLatency": 2000,
      "initRef": "init-audio",
      "role": "audio",
      "codec":"mp4a.40.5",
      "samplerate":48000,
      "channelConfig":"2",
      "bitrate":67071
    }
   ],
  "initDataList": [
    {
      "id": "init-hd",
      "type": "inline",
      "data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQ..."
    },
    {
      "id": "init-md",
      "type": "inline",
      "data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQ..."
    },
    {
      "id": "init-sd",
      "type": "inline",
      "data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQ..."
    },
    {
      "id": "init-audio",
      "type": "inline",
      "data": "AAAAHGZ0eXBjbWYyAAAAAGNtZjJpc282bXA0MQ..."
    }
  ]
}

This is one section of CMSF- a CMAF compliant implementation of MOQT Streaming Format, rendered per-section for quick reference and citation. The authoritative text is draft-ietf-moq-cmsf-01 at the IETF.