#! /bin/sh

for arg; {
    if [ -f "$arg" ]; then
        vidfile=$arg
    else
        eval "$arg"
    fi
}

if [ ! $vidfile ]; then
    echo usage: ${0##*/} [key=value] file [key=value]
    exit 1
fi

tplname=${tplname:-$(mktemp -u ani_XXXX)}
frames=${frames:-15}
seek=${seek:-90}
rate=${rate:-10}
width=${width:-320}

trap 'rm -f ${tplname}_*.png; pkill -f -- -nosub' exit int

mplayer -slave -really-quiet -nosound -benchmark \
        -vo yuv4mpeg:file=/dev/stdout \
        -nosub -ss $seek -sws 9 -vf-add scale=$width:-2,$filters "$vidfile" |
        ffmpeg -i - -r $rate -vframes $frames \
        ${tplname}_%3d.png

if [ ${png+png} ]; then
    apngasm $tplname.png ${tplname}_001.png 1 $rate
else
    convert -verbose -layers optimize -delay 1x$rate ${tplname}_\*.png $tplname.gif
fi