How to obtain FPS using mp4parser?

Question

Framerate can be calculated as

FPS = framescale / timescale

Timescale is easy to obtain using isoFile.getMovieBox().getMovieHeaderBox().getTimescale()

But I cannot figure out where is the framescale stored within the mp4parser isobox structure.

Some sample code I came across here uses low-level buffer read on the following path: /moov/trak/mdhd, but that doesn't seem to be accessible using mp4parser.

Question: Is it possible to extract framescale and/or framerate using mp4parser? Or is it better to use ffmpeg instead?

Note: I prefer using native libraries such as mp4parser over external executables (ffmpeg) where possible

score 2 · Accepted Answer · answered Oct 01 '19 at 13:53

This is an old question, but here is how you can get the frame rate using Mp4Parser:

for(int i=0; i<video.getTracks().size();i++){
    Track videoTrack = video.getTracks().get(i);
    if(videoTrack.getHandler().equals("vide)){
        TrackMetaData metaData = videoTrack.getTrackMetaData();
        //Get timescale
        long timeScale = metaData.getTimescale();
        //Get video duration in Us
        long durationUs = videoTrack.getDuration() * 1000 *1000 / timeScale;
        //Get total frames
        long totalFrames = videoTrack.getSamples().size();
        //Calculate the frame duration
        long perFrameDurationUs =  durationUs /  totalFrames;
        //FPS
        long fps = 1000 * 1000 / perFrameDurationUs;
    }
}

video is refering to Movie video = MovieCreator.build(filePath);

How to obtain FPS using mp4parser?

1 Answers1