#!/bin/bash

orig="$1_orig"

cp $1 $orig

magick $1 -level 0x70% -set option:distort:viewport '%wx%h+0+0' -colorspace CMYK -separate null: \( -size 2x2 xc: \( +clone -negate \) +append \( +clone -negate \) -append \) -virtual-pixel tile -filter gaussian \( +clone -distort SRT 60 \) +swap \( +clone -distort SRT 30 \) +swap \( +clone -distort SRT 45 \) +swap \( +clone -distort SRT 0 \)  +swap +delete -compose Overlay -layers composite -set colorspace CMYK -combine -colorspace RGB "$1_ver1"

magick "$1_ver1" -colorspace gray "$1_ver2"

magick "$1_ver2" -ordered-dither h16x16o "$1"

rm -rf "$1_ver1" "$1_ver2"