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getCanExtractFramesFast()

Available since v3.3.2 - Part of the @remotion/renderer package.

Probes whether frames of a video can be efficiently extracted when using <OffthreadVideo>.

ts
import { getCanExtractFramesFast } from "@remotion/renderer";
 
const result = await getCanExtractFramesFast({
  src: "/var/path/to/video.mp4",
});
 
console.log(result.canExtractFramesFast); // false
console.log(result.shouldReencode); // true
ts
import { getCanExtractFramesFast } from "@remotion/renderer";
 
const result = await getCanExtractFramesFast({
  src: "/var/path/to/video.mp4",
});
 
console.log(result.canExtractFramesFast); // false
console.log(result.shouldReencode); // true

When to use this API​

If you are using <OffthreadVideo>, you might get a warning "Using a slow method to extract the frame" if a video is included which does not include enough metadata to efficiently extract a certain frame of a video. This might result in the render becoming slow.

Using this API, you can probe whether this issue affects your video file. It will try to extract the last frame of a video and if it succeeds, your video is not affected. Otherwise, canExtractFramesFast will be false.

How to act on the results​

When canExtractFramesFast is false, you should check the shouldReencode flag. If it is true, you can re-encode the video to make the render faster. Note that it is not always faster to re-encode the video than it is to deal with a slow render.

Videos with a VP8 codec don't support fast frame extraction at all, and therefore shouldReencode can be false even if canExtractFramesFast is false.

Reencoding a video​

You can re-encode a video using FFmpeg:

sh
ffmpeg -i inputvideo.mp4 outputvideo.mp4
sh
ffmpeg -i inputvideo.mp4 outputvideo.mp4

Arguments​

An object containing one or more of the following options:

src​

Pointing to a video file. Must be an absolute file path.

ffmpegExecutable?​

removed in v4.0

string - optional

An absolute path overriding the ffmpeg executable to use.

ffprobeExecutable?​

removed in v4.0, _string, optional

An absolute path overriding the ffprobe executable to use.

Return value​

Returns a promise which resolves to an object with the following parameters:

  • canExtractFramesFast: boolean Whether it will be fast to extract a frame from a video.
  • shouldReencode: boolean Whether the video can be re-encoded to make the render faster.

See also​