go images http://tour.golang.org/#59

image.go

package main

import (
    "code.google.com/p/go-tour/pic"
    "image"
    "image/color"
)

type Image struct{
    w, h int
    pixels [][]color.RGBA   
}

func (img Image) ColorModel() color.Model {
    return color.RGBAModel
}

// Bounds returns the domain for which At can return non-zero color.
// The bounds do not necessarily contain the point (0, 0).
func (img Image) Bounds() image.Rectangle {
    return image.Rect(0, 0, img.w, img.h)
}

// At returns the color of the pixel at (x, y).
// At(Bounds().Min.X, Bounds().Min.Y) returns the upper-left pixel of the grid.
// At(Bounds().Max.X-1, Bounds().Max.Y-1) returns the lower-right one.
func (img Image) At(x, y int) color.Color {
	return img.pixels[x][y]
}

func Img(w, h int) Image {
    pixels := make([][]color.RGBA, w)
                   
    for i := 0; i < w; i++ {
        pixels[i] = make([]color.RGBA, h)
    }
                   
    for i := 0; i < w; i++ {
        for j := 0; j < h; j++ {
            pixels[i][j] = color.RGBA{uint8(w), uint8(w+j), uint8(h-j), 25}
        }
    }
    return Image{w, h, pixels}              
}

func main() {
    m := Img(122,33)
    pic.ShowImage(m)
}