Simple program to undiff TIFF horizontally diffed files

tiff-hdiff.go

package main

// Run like `cat my.dif | go run tiff-hdiff.go`

import (
	"bufio"
	"fmt"
	"os"
)

func main() {
	reader := bufio.NewReader(os.Stdin)

	height := 512
	width := 512

	var lastVal uint32
	var currentVal uint32
	b := make([]byte, 0, height*width)
	for row := 0; row < height; row++ {
		for col := 0; col < width; col++ {

			currentByte, err := reader.ReadByte()
			if err != nil {
				panic(err)
			}
			if col == 0 {
				currentVal = uint32(currentByte)
			} else {
				currentVal = lastVal - uint32(currentByte)
			}
			b = append(b, byte(currentVal))
			lastVal = currentVal
		}
	}

	// Write decompressed Bytes to stdout
	w := bufio.NewWriter(os.Stdout)
	n, err := w.Write(b)
	if err != nil {
		panic(err)
	}
	w.Flush()

	// Print summary
	fmt.Fprintf(os.Stderr, "%d bytes dediffed\n", n)
}