There are a lot of interesting lectures on Youtube. Recently I’ve taken to adding these lectures to a playlist and processing them on my mac using the following script:
youtube-dl -o '%(stitle)s.%(ext)s' $YOUR_YOUTUBE_PLAYLIST for file in ./*.mp4; do echo "processing $file" file = $(print '%q' "$file") ffmpeg -i "$file" -filter:a "atempo=2.0, pan=stereo|c1<c0+c1" -c:a libmp3lame -q:a 4 "$file.mp3" done rm -rf *.mp4
You’ll need youtube-dl and ffmpeg installed for this script to work. Both of these are available from brew.
This script also encodes the youtube video at 2x speed and combines the left and right channels into the right channel. Remove the filter flag if you don’t want your files processed this way.