indices with strftime are incompatible.

[elias tsolis]

command:
ffmpeg -rtbufsize 100M -vsync 0 -vf "select='$frms'" -fps_mode passthrough -strftime 1 frames/"%Y-%m-%d_%H-%M-%S_%5d.bmp" -i "${vid_scr}"

problem:
extracting multiple frames from multiple splitted videos, in automated way using ffmpeg, in an ordered way, with timestamp+increment of index is impossible. Think of multiple videos (vid01.mp4 vid02.mp4) recorded at 50 fps / 128 etc.

When you try to extract these thumbnails all will start as "00001.jpg, 00002.jpg". which will overwrite them. Otherwise you must make a differect directory for each video which is inconvenient.

I have read that strftime cannot work with miliseconds or with other incremented indices.

So this is a problem.

Solution
strftime must define only time and must work with other incremental indices. Also, it must support miliseconds & nanoseconds. There are some addons that do that.

I tried to set the time outside ffmpeg as variable but do not "renew" it. it stuck on same number.

dtmil="$(date +"%T.%N")";

ffmpeg -rtbufsize 100M -vsync 0 -vf "select='$frms'" -fps_mode passthrough frames/"$dtmil_%5d.bmp" -i vid01.mp4

system: linux debian

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