#!/bin/bash

if [ $# -eq 0 ]; then
    echo "extract_themis_thumbnail.sh {filename.pgm.gz}"
    exit 1
fi

zcat $1 | pnmscale -xsize 100 -ysize 100 | pnmnorm -bvalue 3000 -wvalue 20000 2>/dev/null | pnmdepth 255 |pnmgamma 2|  pgmtoppm rgb:00/00/00-rgb:FD/FD/FD | ppmtopgm | pnmtopng 2>/dev/null