ffmpeg -i you.s02e05.mkv -itsoffset 0.5 -i you.s02e05.mkv -map 1:v -map 0:a -c copy you.s02e05_fixed.mkv If you want a good balance of size, quality, and device compatibility:
ffmpeg -i you.s02e05.mkv Even without output, ffmpeg prints stream information: video codec (h264, h265), audio channels, subtitle tracks, duration, bitrate. you s02e05 ffmpeg
ffmpeg -i you.s02e05.mkv -c:v libx264 -c:a aac you.s02e05.mp4 Take a frame at 00:15:30 and save as JPEG: ffmpeg -i you