added PNGizer

pngizer.sh

@@ -0,0 +1,72 @@
+#!/bin/sh
+# PNGizer: convert any file into PNG image and back
+# Depends on mktemp, tar, ImageMagick and pngcrush
+# Created by Luxferre in 2026, released into public domain
+
+# Convert any raw data file to PNG
+# Usage: pngize_raw $infile $pngfile
+pngize_raw() {
+  temp_ppm="$(mktemp)"
+  # get raw input size 
+  fsize=$(wc -c < "$1")
+  # calculate image side length to fit everything
+  sidelen=$(echo "scale=0;1 + sqrt($fsize / 3 + 1)" | bc -l)
+  # how many trailing zero bytes we need 
+  remlen=$((sidelen * sidelen * 3 - fsize))
+  # shape the PPM file:
+  # 1. header (PPM binary)
+  printf 'P6\n%s %s\n255\n' $sidelen $sidelen > $temp_ppm
+  # 2. body (raw file data)
+  cat "$1" >> $temp_ppm
+  # 3. trailing zero bytes
+  for i in $(seq 1 $remlen); do printf '\x00' >> $temp_ppm; done
+  # convert PPM to PNG and remove the temporary PPM
+  magick ppm:$temp_ppm png:$ofile
+  rm -f $temp_ppm
+}
+
+# extract any raw data file from PNG
+# Usage: unpngize_raw $pngfile $outfile
+unpngize_raw() {
+  temp_ppm="$(mktemp)"
+  # convert PNG to PPM (should be P6)
+  magick png:$1 ppm:$temp_ppm
+  # extract the raw body
+  tail -n +4 $temp_ppm > $2
+  # remove the temporary PPM
+  rm -f $temp_ppm
+}
+
+# Convert any file or directory to PNG
+pngize() {
+  ofile="$2"
+  [ -z "$2" ] && ofile="$1.png"
+  temp_arch="$(mktemp)"
+  # containerize the input 
+  tar cf $temp_arch "$1"
+  # run the conversion
+  pngize_raw $temp_arch $ofile
+  rm -f $temp_arch
+  # apply compression
+  pngcrush -ow $ofile
+}
+
+# Extract the file or directory from PNG
+unpngize() {
+  temp_arch="$(mktemp)"
+  unpngize_raw "$1" $temp_arch
+  tar xf $temp_arch
+  rm -f $temp_arch
+}
+
+# entry point
+
+[ -z "$2" ] && echo 'No input file specified! Exiting...' && exit 1
+if [ "$1" = "e" ]; then
+  [ -z "$3" ] && echo "No output file specified! Using $2.png as output file"
+  pngize "$2" "$3"
+elif [ "$1" = "d" ]; then
+  unpngize "$2"
+else
+  echo 'Invalid mode! Use e for encoding or d for decoding'
+fi