png2mozjpeg.sh

#!/bin/bash

Q=85

while [[ $# > 1 ]]
do
key="$1"

if [ $2 ]
then
  case $key in
      -q|--quality)
      Q="$2"
      shift # past argument
      ;;
      -s|--sample)
      SAMPLE="$2"
      shift # past argument
      ;;
      -t|--quant-table)
      QUANT_TABLE="$2"
      shift # past argument
      ;;
      *)
            # unknown option
      ;;
  esac
fi
shift # past argument or value
done

INPUT="$1"

if [ ! $INPUT ]
then
  echo "Usage: png2mozj [options] <png-image>"
  echo "Options:"
  echo "  -q, --quality      e.g. 95"
  echo "  -s, --sample       e.g. 1x1"
  echo "  -t, --quant-table  e.g. 2"
  echo ""
  exit 0
fi

OUTPUT=`echo $INPUT | sed 's/png$/jpg/'`

if [[ -x `which mozcjpeg` ]]
then
  EXE="mozcjpeg"
elif [[ -x `which mozjpeg` ]]
then
  EXE="mozjpeg"
elif [[ -x `which cjpeg` ]]
then
  EXE="cjpeg"
else
  echo "Executable not found"
  exit 1
fi

args=()

if [ $Q ]
then
  args+=("-quality")
  args+=($Q)
fi
if [ $SAMPLE ]
then
  args+=("-sample")
  args+=($SAMPLE)
fi
if [ $QUANT_TABLE ]
then
  args+=("-quant-table")
  args+=($QUANT_TABLE)
fi

AA=$(IFS=" " ; echo "${args[*]}")

echo "convert $INPUT pnm:- | $EXE $AA > $OUTPUT"
convert $INPUT pnm:- | $EXE $AA > $OUTPUT