[bilibili] Recover mp4 from audio.m4s and video.m4s

makeMP4.sh

#!/bin/zsh

output_dir="videos"

if [[ ! -e "$output_dir" ]]; then
  mkdir "$output_dir"
fi

for i in */*; do
  if [[ -d $i ]]; then
    idx=${i%/*}
    if [[ ${#idx} -eq 1 ]]; then
      idx="0${i%/*}" # 1 -> 01
    fi
    output_file="$output_dir/$idx.mp4"
    # echo "$output_file"
    ffmpeg -i "$i/audio.m4s" -i "$i/video.m4s" -c copy "$output_file"
  fi
done