[ffmpeg] Create video from a still image and an audio file

create_image_audio.sh

function create_image_audio() {
  local -r image="$1"
  local -r audio="$2"
  echo DEBUG: $(pwd)
  echo DEBUG: $(file "$image")
  echo DEBUG: $(file "$audio")
  ffmpeg -loop 1 -i "$image" -i "$audio" -c:v libx264 -c:a copy -shortest "${audio}.mp4"
}
create_image_audio "$1" "$2"

# example:
#   find . -name '*.mp3' -print0 | tr -d '\012' | xargs -0 -I {} ./create_image_audio.sh <IMAGE> {}