progressibejpg.go

gistfile1.txt

package main

import (
	"bufio"
	"log"
	"os"

	ljpg "github.com/pixiv/go-libjpeg/jpeg"
)

func main() {
	// Decoding JPEG into image.Image
	io, err := os.Open("lenna.jpg")
	if err != nil {
		log.Fatal(err)
	}
	img, err := ljpg.Decode(io, &ljpg.DecoderOptions{})
	if err != nil {
		log.Fatalf("Decode returns error: %v\n", err)
	}

	// Encode JPEG
	f, err := os.Create("outlenna.jpg")
	if err != nil {
		panic(err)
	}
	w := bufio.NewWriter(f)
	if err := ljpg.Encode(w, img, &ljpg.EncoderOptions{Quality: 90, ProgressiveMode: true}); err != nil {
		log.Printf("Encode returns error: %v\n", err)
		return
	}
	w.Flush()
	f.Close()
}