Use Firefox, otherwise audio is not captured

  1. Choose a local mp4 file
  2. Optionally: Make a crop selection by clicking on the button and dragging a box on the video. Finish your selection by clicking the button again.
  3. Seek the video to the start position where the recording should start.
  4. Start recording by clicking the button. This will play the video in real time. Stop recording by clicking the button again.
  5. A download link will appear at the bottom of the page. Left click it.

Choose mp4 files:

crop