If you are trying to create or extract a feature from a video file, here are the most likely methods: : Use Online-Convert to change formats.
Use a shell script to generate thumbnails for a directory of MP4s. : 3b (113).mp4
If this is from a specific textbook, software, or scientific study, please share: The (e.g., Biology, Programming, Engineering). If you are trying to create or extract
The (e.g., "I need to see the animation for cell division"). or scientific study
: Supplement files for academic papers (e.g., Supplementary Video 3b or Fig 3B animations).
: Video clips attached to specific manual sections (e.g., Chapter 3b , item 113 ).
The (e.g., "From my Epson projector manual" or "From a Coursera course").