20 numbered original pictures in FFV1/Matroska. FFmpeg 6.1.1; explicit encoder time base 1/1000. Decode the files with compatible software. Results record source indices for four selection rules. The Python script creates a new selection-numbered folder beside itself; run in a clean folder and install FFmpeg/FFprobe first.

Synthetic examples created for ExtractVideoFrames.com. Original example media and illustration data: CC0. FFmpeg, Python, Pillow and ImageMagick are separate tools with their own licenses. Source programs do not delete existing directories; use a new working folder. No private media is included.
