HowTo

Make a sample ffv1 version 3 file in Matroska.

ffmpeg -f lavfi -i mandelbrot -t 1 -c:v ffv1 -level 3 -g 1 test_ffv1_v3.mkv

Assess ffv1/mkv with mediainfo

mediainfo --inform="Details;1" test_ffv1_v3.mkv

Assess mkv with exiftool (adjust verbosity 1-5)

exiftool -v2 test_ffv1_v3.mkv

Play with ffv1 debugging

ffplay -debug 1 testffv13broken.mkv

Make a broken jpg and assess with exiftool

ffmpeg -f lavfi -i mandelbrot -vframes 1 hey_%01d.jpg
head -c 30000 hey_1.jpg > hey_broken.jpg
exiftool -v5 hey_broken.jpg 

Make a tiny mkv file

ffmpeg -f lavfi -i color=c=black:s=2x2 -pix_fmt gray -c:v rawvideo -vframes 1 little.mkv