VideoDecoder.configure()

const canvas = document.querySelector('canvas');
const ctx = canvas.getContext('2d');

const decoder = new VideoDecoder({
  output: (frame) => {
    ctx.drawImage(frame, 0, 0);
    frame.close(); // Speicher sofort freigeben!
  },
  error: (e) => console.error('Decoder-Fehler:', e.message)
});

decoder.configure({
  codec: 'vp09.00.10.08',
  codedWidth: 1280,
  codedHeight: 720
});

console.log(decoder.state);

const config = {
  codec: 'avc1.64001F', // H.264 High Profile, Level 3.1
  codedWidth: 1920,
  codedHeight: 1080,
  hardwareAcceleration: 'prefer-hardware'
};

const setupDecoder = async () => {
  const { supported, config: normalized } = await VideoDecoder.isConfigSupported(config);
  if (!supported) {
    console.warn('Konfiguration nicht unterstützt:', config.codec);
    return null;
  }
  const decoder = new VideoDecoder({
    output: (frame) => frame.close(),
    error: console.error
  });
  decoder.configure(normalized);
  return decoder;
};

setupDecoder().then((d) => console.log(d?.state ?? 'kein Decoder'));

// avcCBytes stammt z. B. aus einem MP4-Demuxer (mp4box.js)
const configureFromTrack = (decoder, track, avcCBytes) => {
  decoder.configure({
    codec: track.codec,          // z. B. 'avc1.42E01E'
    codedWidth: track.video.width,
    codedHeight: track.video.height,
    description: avcCBytes,      // Uint8Array mit avcC-Box-Inhalt
    optimizeForLatency: true
  });
};

const decoder = new VideoDecoder({ output: (f) => f.close(), error: console.error });
configureFromTrack(
  decoder,
  { codec: 'avc1.42E01E', video: { width: 640, height: 360 } },
  new Uint8Array([0x01, 0x42, 0xe0, 0x1e, 0xff, 0xe1])
);
// Erster Chunk nach configure() muss ein Schlüsselbild sein
console.log(decoder.state);