Convert video to gif with given resolution

convert-video-to-gif

#!/bin/sh

NAME=""
SCALE=""
PRESET="blog"

function parse_arg_input_file() {
  NAME="$1"
  return 0;
}

function parse_arg_resolution() {
  SCALE="$1"
  return 0;
}

function parse_arg_preset() {
  ARG=$1;
  if [[ $ARG == "wmp" ]]; then
    PRESET="wmp"
    return 0;
  fi
  if [[ $ARG == "blog" ]]; then
    PRESET="blog"
    return 0;
  fi
  echo "Unrecognized preset: $ARG.";
  return 1;
}

function arg_parse() {
  ARG=$1;
  if [[ "$CONSECUTIVE_ARG_PARSE_KIND" == "--input-file" ]]; then
    CONSECUTIVE_ARG_PARSE_KIND=None
    parse_arg_input_file "$ARG";
    return $?;
  fi
  if [[ "$CONSECUTIVE_ARG_PARSE_KIND" == "--resolution" ]]; then
    CONSECUTIVE_ARG_PARSE_KIND=None
    parse_arg_resolution "$ARG";
    return $?;
  fi
  if [[ "$CONSECUTIVE_ARG_PARSE_KIND" == "--preset" ]]; then
    CONSECUTIVE_ARG_PARSE_KIND=None
    parse_arg_preset "$ARG";
    return $?;
  fi
  if [[ "$CONSECUTIVE_ARG_PARSE_KIND" -ne "None" ]]; then
    echo "Invalid consecutive argument: $CONSECUTIVE_ARG_PARSE_KIND. There must be something behind it."
    return 1;
  fi
  if [[ $ARG == "--input-file" ]]; then
    CONSECUTIVE_ARG_PARSE_KIND="$ARG";
    return 0;
  fi
  if [[ $ARG == "--resolution" ]]; then
    CONSECUTIVE_ARG_PARSE_KIND="$ARG";
    return 0;
  fi
  if [[ $ARG == "--preset" ]]; then
    CONSECUTIVE_ARG_PARSE_KIND="$ARG";
    return 0;
  fi
  echo "Unrecognized argument: $ARG.";
  return 1
}

for EACH_ARG in "$@"; do
  arg_parse "$EACH_ARG"
  RET_VAL=$?
  if [[ $RET_VAL -ne 0 ]]; then
    exit 1
  fi
done

FILENAME=$(basename -- "$NAME")
EXT_NAME="${FILENAME##*.}"
FILENAME="${FILENAME%.*}"
FRAME_RATE=24
DELAY=2.5
OPTIMIZE_ARGS=""

BUILD_DIR="$FILENAME.d"

case $PRESET in
  "blog")
    FRAME_RATE=24
    DELAY=2.5
    ;;
  "wmp")
    FRAME_RATE=10
    DELAY=6
    OPTIMIZE_ARGS="-fuzz %3"
    ;;
  *)
    echo "Unkown product category $CATEGORY";
    exit 1;
    ;;
esac

mkdir -p "$BUILD_DIR"

##########################################################################
# DOWNSCALE
##########################################################################

echo "ffmpeg -i \"$NAME\" -s $SCALE \"$BUILD_DIR/$FILENAME.mp4\""

ffmpeg -i "$NAME" -s $SCALE "$BUILD_DIR/$FILENAME.mp4"

##########################################################################
# CREATE PNG
##########################################################################

echo "ffmpeg -i \"$BUILD_DIR/$FILENAME.mp4\" -r $FRAME_RATE -pix_fmt rgb24 \"$BUILD_DIR/ffout%3d.png\""

ffmpeg -i "$BUILD_DIR/$FILENAME.mp4" -r $FRAME_RATE -pix_fmt rgb24 "$BUILD_DIR/ffout%3d.png"

##########################################################################
# COMPOSITION
##########################################################################

echo "convert -delay $DELAY -loop 0 \"$BUILD_DIR/ffout*.png\" \"$BUILD_DIR/$FILENAME.gif\""

convert -delay $DELAY -loop 0 "$BUILD_DIR/ffout*.png" "$BUILD_DIR/$FILENAME.gif"

##########################################################################
# OPTIMIZE
##########################################################################

# TOOD: -fuzz %n, specifies that colors within a certain tolerance can be considered as the same color. 

echo "convert -layers Optimize $OPTIMIZE_ARGS \"$BUILD_DIR/$FILENAME.gif\" \"$BUILD_DIR/$FILENAME-optimized.gif\""

convert -layers Optimize $OPTIMIZE_ARGS "$BUILD_DIR/$FILENAME.gif" "$BUILD_DIR/$FILENAME-optimized.gif"