content-aware-scale

#!/usr/bin/env fish
# content-aware scale a video.
# https://www.imagemagick.org/Usage/resize/#liquid-rescale
# requirements:
# - fish (to actually run the script; bash isn't used because bash sux)
# - ffmpeg (to convert the video to images and audio and back again)
# - imagemagick (to process the images; actually apply the liquid-rescale)
# - parallel (to run multiple imagemagick in parallel and make the processing happen faster)
# - sox (to process the audio)
# - tap-plugins (for the vibrato effect)

set input $argv[1]
set resize $argv[2] # FIX: strip off % and have a default if none is provided

echo Input: $input
echo This is a ... video? # FIX: make it work on images too
echo Resize to: $resize

set resize_back_to (math 100 / $resize '*' 100)

# set tmp_dir (mktemp -d content-aware-scale-XXXX)

set tmp_dir content-aware-scale-$input

echo Using temporary directory $tmp_dir

mkdir $tmp_dir

ffmpeg -i $input "$tmp_dir/output_%06d.jpg"

ffmpeg -i $input "$tmp_dir/$input.wav"

cd $tmp_dir

parallel --progress --joblog log.txt --nice 10 "convert {} -liquid-rescale $resize% -resize $resize_back_to% res_"$resize"_{}" ::: output_*.jpg

# read -P "Finished rescaling video frames. Saved audio to $tmp_dir/$input.wav ; press enter to continue re-creating the video with the rescaled frames and this audio file."

set vib_freq (random 2 6).(random 0 10000)

echo "Vibrato frequency: $vib_freq"

sox $input.wav vibrato-$input.wav norm ladspa -r tap_vibrato $vib_freq 20

# FIX: this probably needs -r for the frame rate and -s for the size/dimensions
ffmpeg -i vibrato-$input.wav -f image2 -i "res_"$resize"_output_%06d.jpg" -vcodec libx264 -crf 25 -pix_fmt yuv420p content-aware-$input

echo "Done! Output saved to ./content-aware-$input . Temporary directory used: $tmp_dir ."