binary2png.go

package main

import (
	"flag"
	"fmt"
	"image"
	"image/color"
	"image/png"
	"io/ioutil"
	"log"
	"os"
)

func main() {
	var (
		outfile = flag.String("outfile", "out.png", "")
		width   = flag.Int("width", 128, "")
		bcolor  = flag.Bool("color", false, "")
	)
	flag.Parse()

	if flag.NArg() != 1 {
		fmt.Fprintf(os.Stderr,
			"Usage: %s [--width=%%d] [--outfile=%%s] filename\n", os.Args[0])
		os.Exit(1)
	}
	filename := flag.Args()[0]

	file, err := os.Open(filename)
	if err != nil {
		log.Fatal(err)
	}
	defer file.Close()
	buf, err := ioutil.ReadAll(file)
	if err != nil {
		log.Fatal(err)
	}

	m := image.NewRGBA(image.Rect(0, 0, *width, (len(buf)-1) / *width + 1))
	for i, c := range buf {
		var bitColor color.RGBA
		if (*bcolor) {
			if c == 0x00 {
				bitColor = color.RGBA{255, 255, 255, 255}
			} else if 0x01 <= c && c <= 0x1f {
				bitColor = color.RGBA{0, 255, 255, 255}
			} else if 0x20 <= c && c <= 0x7f {
				bitColor = color.RGBA{255, 0, 0, 255}
			} else if 0x80 <= c && c <= 0x9f {
				bitColor = color.RGBA{255, 255, 0, 255}
			} else if 0xa0 <= c && c <= 0xfe {
				bitColor = color.RGBA{255, 0, 255, 255}
			} else if c == 0xff {
				bitColor = color.RGBA{0, 0, 0, 255}
			}
		} else {
			if c == 0x00 {
				bitColor = color.RGBA{255, 255, 255, 255}
			} else if 0x01 <= c && c <= 0x1f {
				bitColor = color.RGBA{0, 255, 255, 255}
			} else if 0x20 <= c && c <= 0x7f {
				bitColor = color.RGBA{255, 0, 0, 255}
			} else if 0x80 <= c && c <= 0xff {
				bitColor = color.RGBA{0, 0, 0, 255}
			}
		}
		m.Set(i%*width, int(i / *width), bitColor)
	}

	img, err := os.Create(*outfile)
	if err != nil {
		log.Fatal(err)
	}
	defer img.Close()
	png.Encode(img, m)
}