[FFmpeg-user] ffmpeg whole directory file conversion question

[Ashley Smiley]

Hello,

I am writing to ask advice about how to augment my ffmpeg command line. I
am working through my iMac's Terminal.

The task I am trying to perform is to convert a whole directory of .mp4
files (all with unique filenames) to .png images whose labels correspond to
their original .mp4 files.

The line I've run is:

*for i in *.mp4; *

*do ffmpeg -1 "$i" image%03d.png; *

*done*

This command line batch converts all .mp4 files to continuous .png files.
That is, when moving from video 1 to video 2, the labeling does not start
all over to indicate a break between video files. I would like to insert
label breaks so that I can track which images correspond to which video and
know exactly how many frames exist per video by conveniently having them
labeled starting from 0 or 1 each time.

However, I don't know how to do this as I've searched online for a few days
and I think it's time for suggestions.

An example list of filenames:

calib_checker_22sep18_154022_top_1x1cm.*mp4*
calib_checker_22sep18_154022_side_1x1cm.*mp4*
calib_ball_22sep18_154750_top*.mp4*
calib_ball_22sep18_154930_side.*mp4*

and I want each to have a list of corresponding .pngs, i.e.:

calib_checker_22sep18_154022_top_1x1cm_*001.png*
calib_checker_22sep18_154022_top_1x1cm_*002.png*
calib_checker_22sep18_154022_top_1x1cm_*003.png*

calib_checker_22sep18_154022_side_1x1cm_*001.png*
calib_checker_22sep18_154022_side_1x1cm_*002.png*

calib_ball_22sep18_154750_top_*001.png.*....etc.

calib_ball_22sep18_154930_side_*001.png*....etc.

One last note:

The reason I want to batch process is because there are at least 64 video
files in the directory total.

Sincerely,

Ashley Smiley
-- 
Ashley Smiley
Ph.D. Candidate, Dudley Lab
Department of Integrative Biology
University of California, Berkeley
berkeleyflightlab.org