NorskTransform.streamMetadataOverride() method

// SRT inputs do not have bitrate information, which is required for HLS
// multi variant playlists.
//
// AAC audio does not need a transcode in this setting, and without a
// transcode (implicit or explicit), there is no bitrate information added.
const srtAacInput = await norsk.input.srt(srtSettings);

// So we sample the stream for 10 seconds to estimate its bitrate and add this
// bitrate to the stream's metadata before subscribing the multi variant playlist to
// the stream.
let streamStarted = false;
const streamStatistics = await norsk.processor.control.streamStatistics({
  id: "inputStreamStatistics",
  statsSampling: {
    // 1s for visualiser updates
    // 5s for console updates
    // 10s for stream bitrate estimation
    sampleIntervalsSeconds: [1, 5, 10],
  },
  onStreamStatistics: async stats => {
    const { audio, video } = stats;
    if (stats.sampleSizeSeconds === 10) {
      if (streamStarted) return;
      streamStarted = true;
      console.log(`+ audio: ${(audio.bitrate / 1000).toFixed(1)}kbps`)
      console.log(`+ video: ${(video.bitrate / 1000).toFixed(1)}kbps`);

      // Use NorskTransform.streamMetadataOverride to add bitrate information
      // to the video and audio streams
      streamMetadataOverride.updateConfig({
        video: {
          bitrate: video.bitrate,
        },
        audio: {
          bitrate: audio.bitrate,
        }
      });

      // And subscribe the multi variant playlist, now that the stream has bitrate
      // metadata
      // multiVariantOutput.subscribe([
      //   { source: streamMetadataOverride, sourceSelector: selectPlaylist },
      // ]);
    } else if (stats.sampleSizeSeconds === 5 && streamStarted) {
      console.log(`  audio: ${(audio.bitrate / 1000).toFixed(1)}kbps`)
      console.log(`  video: ${(video.bitrate / 1000).toFixed(1)}kbps`);
    }
  },
});
streamStatistics.subscribe([
  { source: srtAacInput, sourceSelector: selectAV },
]);

const streamMetadataOverride = await norsk.processor.transform.streamMetadataOverride({
  id: "setBitrate",
});
streamMetadataOverride.subscribe([
  { source: srtAacInput, sourceSelector: selectAV },
]);

ffmpeg -v error -re -stream_loop -1 -i data/InkDrop.ts  -vcodec copy -codec copy -f mpegts -flush_packets 0 'srt://127.0.0.1:5001?pkt_size=1316'