Answer by Louis Maddox for FFMPEG- Convert video to images

In addition to the select filter in Gyan's answer (which I use with eq rather than between), I came across another filter in the manual: thumbnail

Select the most representative frame in a given sequence ofconsecutive frames.

The filter accepts the following options:

• n: Set the frames batch size to analyze; in a set of n frames, the filter will pick one of them, and then handle the next batch of nframes until the end. Default is 100.

Since the filter keeps track of the whole frames sequence, a bigger nvalue will result in a higher memory usage, so a high value is notrecommended.

Examples

• Extract one picture each 50 frames:

  thumbnail=50

• Complete example of a thumbnail creation with ffmpeg:

  ffmpeg -i in.avi -vf thumbnail,scale=300:200 -frames:v 1 out.png