Quick Shell Script to run my edge detection algorithm on a given video file

run.sh

# use with https://github.com/Wuelle/Sobel-operator
# Create tmp directories
mkdir _tmp
mkdir _tmp/img
mkdir _tmp/processed

# Extract audio and source images from the input file
ffmpeg -nostdin -i input.mp4 _tmp/img/%06d.png
ffmpeg -nostdin -i input.mp4 _tmp/audio.mp3

# Apply the edge detection 
NUM_IMG=$(ls _tmp/img/ | wc -l)
CURR_IMG=0

for filename in _tmp/img/*; do
    BASE=$(basename $filename)
    echo "[${CURR_IMG}/${NUM_IMG}]: $BASE"
    python3 edge_detection.py ${filename} "_tmp/processed/$BASE"
    CURR_IMG=$((CURR_IMG+1))
done

# Concatenate images into (silent) video
ffmpeg -nostdin -i _tmp/processed/%06d.png _tmp/silent.mp4

# Add the audio back in
ffmpeg -nostdin -i _tmp/silent.mp4 -i _tmp/audio.mp3 output.mp4

# Cleanup
rm -rf _tmp