Loops

This is a basic (bash) loop to operate on files.

Examples are given for 7z and video conversion.

#!/bin/bash -x
#for i in *.webm;
        for i in *.7z
 do name=`echo $i | cut -d'.' -f1`;
 echo $name;

#for h264
# ffmpeg -i $i -s 1280x720 -c:a copy $name.mp4;

#for webm

#-map_metadata -1 is to remove metadata, at least try to remove some. (need to verify)
#ffmpeg -i $i -map_metadata -1 -c:v libvpx -crf 10 -b:v 1M -c:a libvorbis $name.webm
 7z e -o"$name" ./"$i" 
done

Basically, trim off extension of i, put into name. Use both for extractions/conversion.

Edit images in bulk

        for i in *.JPG
do
#delete exif data
mogrify -strip $i
#test convert size in gimp first to get ratio right. My source files are 4kx3.5k
convert -resize 1080x810 $i ~/Desktop/phatch/$i
done

• https://hackaday.com/2020/06/12/binary-math-tricks-shifting-to-divide-by-ten-aint-easy/