PSD/PSB(Photoshop) file reader for Go programming language

It works almost well but it is still in development.

How to use

Example1

Simple psd -> png conversion.

package main

import (
	"image"
	"image/png"
	"os"

	_ "github.com/oov/psd"
)

func main() {
	file, err := os.Open("image.psd")
	if err != nil {
		panic(err)
	}
	defer file.Close()

	img, _, err := image.Decode(file)
	if err != nil {
		panic(err)
	}

	out, err := os.Create("image.png")
	if err != nil {
		panic(err)
	}
	err = png.Encode(out, img)
	if err != nil {
		panic(err)
	}
}

Example2

Extract all layer images.

package main

import (
	"fmt"
	"image/png"
	"os"

	"github.com/oov/psd"
)

func processLayer(filename string, layerName string, l *psd.Layer) error {
	if len(l.Layer) > 0 {
		for i, ll := range l.Layer {
			if err := processLayer(
				fmt.Sprintf("%s_%03d", filename, i),
				layerName+"/"+ll.Name, &ll); err != nil {
				return err
			}
		}
	}
	if !l.HasImage() {
		return nil
	}
	fmt.Printf("%s -> %s.png\n", layerName, filename)
	out, err := os.Create(fmt.Sprintf("%s.png", filename))
	if err != nil {
		return err
	}
	defer out.Close()
	return png.Encode(out, l.Picker)
}

func main() {
	file, err := os.Open("image.psd")
	if err != nil {
		panic(err)
	}
	defer file.Close()

	img, _, err := psd.Decode(file, &psd.DecodeOptions{SkipMergedImage: true})
	if err != nil {
		panic(err)
	}
	for i, layer := range img.Layer {
		if err = processLayer(fmt.Sprintf("%03d", i), layer.Name, &layer); err != nil {
			panic(err)
		}
	}
}

Current status

It is not implemented any blending functions because layer composition isn't covered by this package at present.

Image Resource Section is parsed but Image resource IDs are not defined as constant.
Global layer mask info is not parsed.
Layer blending ranges data is not parsed.
Additional Layer Information is parsed but keys are almost not defined as constant.

Color Modes

Implemented

Bitmap 1bit
Grayscale 8bit
Grayscale 16bit
Grayscale 32bit
Indexed
RGB 8bit
RGB 16bit
RGB 32bit
CMYK 8bit
CMYK 16bit

Not implemented

CMYK 32bit
Multichannel
Duotone
Lab

Supported Compression Methods

Raw
RLE(PackBits)
ZIP without prediction (not tested)
ZIP with prediction

chenlexing/psd