#!/bin/sh
def_ratio=1

help(){
	cat <<END
Usage: $0 <filename.[ppm|pnm|png]>
Options:
    -r n      aspect ratio, n=1 4:3, n=2 16:9       ($def_ratio)
    -h        Print this help message
END
    exit 0
}
ratio=$def_ratio

while getopts r:h name "$@"
do
	case $name in
r)
	ratio=$OPTARG ;;
*)
	help ;;
	esac
done
let shiftind=$OPTIND-1
shift $shiftind   

if test "$#" != "1"
then
	help
fi
case $1 in
*.pnm)
	ifilter=cat
	input="$1"
	base=`echo $input | sed "s/\.pnm$//"` ;;
*.ppm)
	ifilter=cat
	input="$1"
	base=`echo $input | sed "s/\.ppm$//"` ;;
*.png)
	ifilter=pngtopnm
	input="$1"
	base=`echo $input | sed "s/\.png$//"` ;;
*)
	help ;;
esac
case $ratio in
2)
    aflag="-a3" ;;
*)
    aflag="-a2" ;;
esac

echo Transcoding $input to $base.mpg....
sleep 1

$ifilter $input |
ppmtoy4m -A10:11 -I p -S 420mpeg2 | 
	mpeg2enc -f7 -nn -T120 $aflag -o $base.m2v
mplex -f7 "$base".m2v -o "$base".mpg