Shell script to label a video using ffmpeg.

label-video

#!/bin/bash
# label-video

function usage() {
   echo "usage: label-video [-tlrb] [-c COLOR] [-s SIZE] [-f FONT.ttf] MESSAGE INPUT.mp4 OUTPUT.mp4";
   echo "    [-tlrb] top, left, right, bottom";
   echo "    -c set text color"
   echo "    -s set text size"
   echo "Adds a label to a video file using ffmpeg."
}

x=10;
y=10;
color="white";
size=24;
font="";

while getopts htbrlc:s:f: opt; do
    case $opt in
      h) usage; exit 0;;
      t) y=10;;
      b) y="h-text_h-10";;
      r) x="w-text_w-10";;
      l) x="10";;
      s) size="$OPTARG";;
      c) color="$OPTARG";;
      f) font=":fontfile=$OPTARG";;
    esac
done
shift $[ OPTIND - 1 ];

if [ $# -ne 3 ]; then
    echo "error: expects three arguments." >&2;
    usage >& 2;
    exit 1;
fi
message="$1";
input="$2";
output="$3";
ffmpeg -i "$input" -vf "drawtext=text='$message'$font:fontcolor=$color:fontsize=$size:x=$x:y=$y" -codec:a copy "$output"