From https://stackoverflow.com/questions/55330848/how-to-recover-corrupted-png-files-due-to-improper-gitattributes
lines=`wc -l < image.corrupted.png`
for x in `seq 1 $((lines+1))`; do
echo -n $x ''
perl -pe 's/$/$1\r/ if ($. == 1 || $. =='$x')' < image.corrupted.png > image.fixed.png
if pngcheck image.fixed.png; then
echo Valid file substituting newline numbers 1 and $x
break
fi
done
