video-editing-process
How I edit teaching videos
Recording
I use two commercial pieces of software for recording videos:
- Microsoft whiteboard for any writing.
- CleanShot for the actual recording.
I record my computer screen with a small video of me being shown in the corner (a feature of Cleanshot). If I am doing any writing then I have a browser window pointed at the same microsoft whiteboard that I am using on my tablet.
If I have written anything on the whiteboard I also export that to a png (thumb.png).
This creates: raw.mp4 and possibly thumb.png.
Initial edit
I use iMovie for quick cuts, crops and trims of the video.
This creates: cut.mp4
Generating subtitles
I use whisper to generate subtitles in .srt format:
$ whisper cut.mp4 --model small --language English
This creates: cut.mp4.srt.
Quality assurance
I watch the video cut.mp4 and read the subtitles file at the same time
main.srt to confirm it is accurate. Possibly making manual edits at this
stage.
Adding hard subtitles
I use ffmpeg to add subtitles to the
video.
$ ffmpeg -i cut.mp4 -vf subtitles=cut.mp4.srt main.mp4
Note that this requires ffmpeg to have libass enabled. Run ffmpeg -version and confirm that —-enable-libass is present in the output.
These are "hard" as opposed to "soft" to make inclusiveness the default.