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canCopyVideoTrack()

warning

We are phasing out Remotion WebCodecs and are moving to Mediabunny!

Part of the @remotion/webcodecs package.

🚧 Unstable API
This package is experimental.
We might change the API at any time, until we remove this notice.

Given a VideoTrack, determine if it can be copied to the output without re-encoding.

You can obtain a VideoTrack using parseMedia() or during the conversion process using the onVideoTrack callback of convertMedia().

Examples​

Check if a video tracks can be copied
tsx
import {parseMedia} from '@remotion/media-parser';
import {canCopyVideoTrack} from '@remotion/webcodecs';
 
const {tracks, container} = await parseMedia({
  src: 'https://commondatastorage.googleapis.com/gtv-videos-bucket/sample/BigBuckBunny.webm',
  fields: {
    tracks: true,
    container: true,
  },
});
 
const videoTracks = tracks.filter((t) => t.type === 'video');
 
for (const track of videoTracks) {
  canCopyVideoTrack({
    outputContainer: 'webm',
    inputTrack: track,
    inputContainer: container,
    rotationToApply: 0,
    resizeOperation: null,
    outputVideoCodec: null,
  }); // boolean
}
Copy a video track to VP8, otherwise drop it
tsx
import {convertMedia, canCopyVideoTrack} from '@remotion/webcodecs';
 
await convertMedia({
  src: 'https://commondatastorage.googleapis.com/gtv-videos-bucket/sample/BigBuckBunny.webm',
  container: 'webm',
  videoCodec: 'vp8',
  audioCodec: 'opus',
  onVideoTrack: async ({track, inputContainer, outputContainer}) => {
    const canCopy = canCopyVideoTrack({
      outputContainer,
      inputTrack: track,
      inputContainer,
      rotationToApply: 0,
      resizeOperation: null,
      outputVideoCodec: null,
    });
 
    if (canCopy) {
      return {type: 'copy'};
    }
 
    // In reality, you would re-encode the track here
    return {type: 'drop'};
  },
});

API​

inputTrack​

string VideoTrack

The input video track.

rotationToApply​

number

The number of degrees to rotate the video track.

inputContainer​

string MediaParserContainer

The container format of the input media.

outputContainer​

string ConvertMediaContainer

The container format of the output media.

resizeOperation​

string ResizeOperation

The resize operation to apply to the video track.

outputVideoCodec​

string | null ConvertMediaVideoCodec

The desired video codec of the output media. If null, it means you don't care about the video codec as long as it can be copied.

Rotation behavior​

Any rotationToApply is in addition to an auto-rotation that is applied by default to fix the orientation of the video track.

If rotationToApply is not the same amount of rotation as inputRotation, this function will always return false, because rotation cannot be performed without re-encoding.

See: Rotating a video

Return value​

Returns a boolean.

See also​