Original timestamps available?

Application Development
1

Hi,

When playing a video from filesrc (.mp4, h264 encoded), is there a possibility to get the original timestamps of when the frame was actually recorded?

2

If the file was recorded with the information, it will be available on each buffer in the form of GstVideoTimecodeMeta.

3

So in Rust, given a valid buffer_ref I should be able to get the VideoTimeCode like so?

        let video_meta_iter = buffer_ref.iter_meta::<VideoTimeCodeMeta>();
          for m in video_meta_iter {
              info!("-- Video Time Code: {:?}", m.tc());
          }

I’ve tried with a .mp4 file, recorded by ffmpeg:

ffmpeg -hide_banner -f v4l2 -video_size 3840x2160 -t 5 -i /dev/video6 -codec:v h264 output_video.mp4

I do receive the buffer, but there seems to be no VideoTimeCodeMeta attached to it, as I don’t see it in the logs. However, PTS and Duration are there.

          let timestamp: u64 = *buffer_ref.pts().unwrap();
          if prev_timestamp > 0 {
              info!("-- PTS: {}, dt: {}", buffer_ref.pts().unwrap(), timestamp - prev_timestamp);
          } else {
              info!("-- first PTS: {}", buffer_ref.pts().unwrap());
          }
  
          if let Some(dts) = buffer_ref.dts() {
              info!("-- DTS: {}", dts);
          }
          if let Some(duration) = buffer_ref.duration() {
              info!("-- duration: {}", duration);
          }

I am actually interested in getting the original dt in between frames. It seems like PTS is the only thing I can currently work with.

Thanks for your input.