Golang gift.New函数代码示例

func varianceF(img image.Image, disk int) (imageF, imageF) {
	m := meanF(img, disk) // gets a grayscale copy of local mean

	// create a grayscale version of the original
	//g := gift.New( gift.Grayscale() )
	//v := image.NewRGBA(g.Bounds(img.Bounds()))
	//g.Draw(v, img)

	g := gift.New(gift.Grayscale())
	dst := image.NewRGBA(g.Bounds(img.Bounds()))
	g.Draw(dst, img)

	bounds := img.Bounds()
	floatData := make([][]float32, bounds.Max.Y-bounds.Min.Y)
	for i := range floatData {
		floatData[i] = make([]float32, bounds.Max.X-bounds.Min.X)
	}
	for y := bounds.Min.X; y < bounds.Max.X; y++ {
		for x := bounds.Min.Y; x < bounds.Max.Y; x++ {
			p1r, p1g, p1b, _ := dst.At(x, y).RGBA()
			g1 := 0.2125*float64(p1r) + 0.7154*float64(p1g) + 0.0721*float64(p1b)
			g2 := float64(m[x][y])

			floatData[x][y] = float32((g1 - g2) * (g1 - g2))
		}
	}
	return m, floatData
}

func makeThumb(source, destination string) error { // {{{
	file, err := os.Open(source)
	if err != nil {
		return err
	}
	defer file.Close()

	// decode jpeg into image.Image
	img, err := jpeg.Decode(file)
	if err != nil {
		return err
	}

	g := gift.New(
		gift.ResizeToFill(200, 200, gift.LanczosResampling, gift.CenterAnchor),
	)

	out, err := os.Create(destination)
	if err != nil {
		return err
	}
	defer out.Close()

	// write new image to file
	dst := image.NewRGBA(g.Bounds(img.Bounds()))
	g.Draw(dst, img)
	return jpeg.Encode(out, dst, &jpeg.Options{100})
}                                                     // }}}

// Render draws rune r front the specified font at the specified dpi and scale.  It returns a
// grayscale image that is just large enough to contain the rune.
func Render(font *truetype.Font, r rune, dpi, scale float64) (*image.Gray, error) {
	glyph := truetype.NewGlyphBuf()
	index := font.Index(r)
	glyph.Load(font, font.FUnitsPerEm(), index, truetype.FullHinting)
	ctx := freetype.NewContext()
	boxer := makeBoundingBoxer()
	ctx.SetSrc(image.NewUniform(color.White))
	ctx.SetDst(boxer)
	ctx.SetClip(boxer.largeBounds)
	ctx.SetFontSize(250)
	ctx.SetDPI(dpi)
	ctx.SetFont(font)
	if err := glyph.Load(font, font.FUnitsPerEm(), font.Index(r), truetype.FullHinting); err != nil {
		return nil, fmt.Errorf("Unable to load glyph: %v\n", err)
	}
	var rp raster.Point
	rp.X = ctx.PointToFix32(0)
	rp.Y = ctx.PointToFix32(100)
	ctx.DrawString(string(r), rp)
	boxer.complete()

	g := gift.New(
		gift.Resize(int(float64(boxer.Bounds().Dx())*scale+0.5), int(float64(boxer.Bounds().Dy())*scale+0.5), gift.CubicResampling),
	)
	dst := image.NewGray(g.Bounds(boxer.Bounds()))
	g.Draw(dst, boxer)
	return dst, nil
}

// TODO Too min images should not resized
func resizeImage(src image.Image, n int) image.Image {
	srcBounds := src.Bounds()
	gi := gift.New(gift.Resize(srcBounds.Max.Y/n, srcBounds.Max.Y/n, gift.LanczosResampling))
	dst := image.NewRGBA(gi.Bounds(srcBounds))
	gi.Draw(dst, src)
	return dst
}

func blur(img image.Image, howmuch float32) image.Image {
	g := gift.New(gift.Grayscale())
	g.Add(gift.GaussianBlur(howmuch))
	dst := image.NewRGBA(g.Bounds(img.Bounds()))
	g.Draw(dst, img)
	return (dst)
}

func (fi *FileInfo) createThumb(buffer *bytes.Buffer, c context.Context) {
	if imageTypes.MatchString(fi.Type) {
		src, _, err := image.Decode(bytes.NewReader(buffer.Bytes()))
		check(err)
		filter := gift.New(gift.ResizeToFit(
			THUMB_MAX_WIDTH,
			THUMB_MAX_HEIGHT,
			gift.LanczosResampling,
		))
		dst := image.NewNRGBA(filter.Bounds(src.Bounds()))
		filter.Draw(dst, src)
		buffer.Reset()
		bWriter := bufio.NewWriter(buffer)
		switch fi.Type {
		case "image/jpeg", "image/pjpeg":
			err = jpeg.Encode(bWriter, dst, nil)
		case "image/gif":
			err = gif.Encode(bWriter, dst, nil)
		default:
			err = png.Encode(bWriter, dst)
		}
		check(err)
		bWriter.Flush()
		thumbnailKey := fi.Key + thumbSuffix + filepath.Ext(fi.Name)
		item := &memcache.Item{
			Key:   thumbnailKey,
			Value: buffer.Bytes(),
		}
		err = memcache.Set(c, item)
		check(err)
		fi.ThumbnailKey = thumbnailKey
	}
}

func mean(img image.Image, disk int) image.Image {
	g := gift.New(gift.Grayscale())
	g.Add(gift.Mean(disk, false)) // use square neighborhood
	dst := image.NewRGBA(g.Bounds(img.Bounds()))
	g.Draw(dst, img)
	return (dst)
}

// DrawPicture .
func DrawPicture(src image.Image, width int, height int) *image.Gray {
	rect := image.Rect(0, 0, width, height)
	img := image.NewGray(rect)
	rander := rander()
	for x := 0; x < width; x++ {
		for y := 0; y < height; y++ {
			var c color.Gray
			if IsBlack(src, x, y) {
				if y > 1 && IsNotBlack(src, x, y-1) {
					c = borderColor(rander)
				} else {
					c = insideColor(rander)
				}
			} else {
				c = outsideColor(rander)
			}
			x1, y1 := transformCurve(x, y, width, height)
			//c = color.Gray{c.Y + ScaledLuminanceAt(90, src, x, y)}
			img.Set(x1, y1, c)
		}
	}
	g := gift.New(
	//gift.GaussianBlur(2),
	)
	img2 := image.NewGray(rect)
	g.Draw(img2, img)
	return img2
}

func analyzeFile(filename string, resize bool) (*Cover, error) {
	file, err := os.Open(filename)

	if err != nil {
		return nil, err
	}

	defer file.Close()

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

	if resize {
		start := time.Now()
		g := gift.New(gift.Resize(500, 0, gift.LanczosResampling))
		dst := image.NewRGBA(g.Bounds(img.Bounds()))
		g.Draw(dst, img)
		img = dst
		fmt.Printf("- RESIZE %s took %s\n", path.Base(filename), time.Since(start))
	}

	start := time.Now()
	bg, c1, c2, c3 := colorart.Analyze(img)
	fmt.Printf("- ANALYZE %s took %s\n", path.Base(filename), time.Since(start))

	return &Cover{filename, bg.String(), c1.String(), c2.String(), c3.String()}, nil
}

func procImage(fileName string) (string, error) {
	reader, err := os.Open(fileName)
	if err != nil {
		fmt.Errorf("Failed to open image with error: %s\n", err)
		return "", err
	}
	defer reader.Close()

	src, _, err := image.Decode(reader)
	if err != nil {
		fmt.Errorf("Failed to decode image with error: %s\n", err)
		return "", err
	}

	g := gift.New(
		gift.Invert(),
	)

	dst := image.NewRGBA(g.Bounds(src.Bounds()))
	g.Draw(dst, src)

	var opt jpeg.Options
	opt.Quality = 100

	fileName = fileName + "_processed.jpg"

	out, _ := os.Create(fileName)
	err = jpeg.Encode(out, dst, &opt)
	if err != nil {
		fmt.Errorf("Failed to encode image with error: %s\n", err)
		return "", err
	}

	return fileName, nil
}

// Sets skin.Processed to an isometric render of the head from a top-left angle (showing 3 sides).
func (skin *mcSkin) GetCube(width int) error {
	// Crop out the top of the head
	topFlat := imaging.Crop(skin.Image, image.Rect(8, 0, 16, 8))
	// Resize appropriately, so that it fills the `width` when rotated 45 def.
	topFlat = imaging.Resize(topFlat, int(float64(width)*math.Sqrt(2)/3+1), 0, imaging.NearestNeighbor)
	// Create the Gift filter
	filter := gift.New(
		gift.Rotate(45, color.Transparent, gift.LinearInterpolation),
	)
	bounds := filter.Bounds(topFlat.Bounds())
	top := image.NewNRGBA(bounds)
	// Draw it on the filter, then smush it!
	filter.Draw(top, topFlat)
	top = imaging.Resize(top, width+2, width/3, imaging.NearestNeighbor)
	// Skew the front and sides at 15 degree angles to match up with the
	// head that has been smushed
	front := skin.cropHead(skin.Image).(*image.NRGBA)
	side := imaging.Crop(skin.Image, image.Rect(0, 8, 8, 16))
	front = imaging.Resize(front, width/2, int(float64(width)/1.75), imaging.NearestNeighbor)
	side = imaging.Resize(side, width/2, int(float64(width)/1.75), imaging.NearestNeighbor)
	front = skewVertical(front, math.Pi/12)
	side = skewVertical(imaging.FlipH(side), math.Pi/-12)

	// Create a new image to assemble upon
	skin.Processed = image.NewNRGBA(image.Rect(0, 0, width, width))
	// Draw each side
	draw.Draw(skin.Processed.(draw.Image), image.Rect(0, width/6, width/2, width), side, image.Pt(0, 0), draw.Src)
	draw.Draw(skin.Processed.(draw.Image), image.Rect(width/2, width/6, width, width), front, image.Pt(0, 0), draw.Src)
	// Draw the top we created
	draw.Draw(skin.Processed.(draw.Image), image.Rect(-1, 0, width+1, width/3), top, image.Pt(0, 0), draw.Over)

	return nil
}

func main() {

	if len(os.Args) != 2 {
		fmt.Println("Usage:\tgoimger <file>")
		os.Exit(1)
	}

	srcFileName := os.Args[1]
	srcFile, _ := os.Open(srcFileName)
	src, _, _ := image.Decode(srcFile)

	// let's make a new gift
	g := gift.New(
		gift.Grayscale(),
		gift.UnsharpMask(1.0, 0.5, 0.0),
	)

	// dest - output image
	dest := image.NewRGBA(g.Bounds(src.Bounds()))
	// draw result
	g.Draw(dest, src)

	outFileName := srcFileName + "_goimger.jpg"
	toimg, _ := os.Create(outFileName)
	defer toimg.Close()

	jpeg.Encode(toimg, dest, &jpeg.Options{jpeg.DefaultQuality})
}

func main() {
	if len(os.Args) != 2 {
		fmt.Println("Usage:\tspiffy <file>")
		os.Exit(1)
	}

	srcFileName := os.Args[1]
	srcFile, _ := os.Open(srcFileName)
	src, _, _ := image.Decode(srcFile)

	// 1. Create a new GIFT and add some filters:
	g := gift.New(
		gift.Grayscale(),
		gift.UnsharpMask(1.0, 1.0, 0.0),
	)

	// 2. Create a new image of the corresponding size.
	// dst is a new target image, src is the original image
	dst := image.NewRGBA(g.Bounds(src.Bounds()))

	// 3. Use Draw func to apply the filters to src and store the result in dst:
	g.Draw(dst, src)

	outFileName := srcFileName + ".spiffy.jpg"
	toimg, _ := os.Create(outFileName)
	defer toimg.Close()

	jpeg.Encode(toimg, dst, &jpeg.Options{jpeg.DefaultQuality})
}

func CropImage(img image.Image, rect image.Rectangle) (croped image.Image) {
	g := gift.New(
		gift.Crop(rect),
	)
	croped_image := image.NewRGBA(g.Bounds(rect))
	g.Draw(croped_image, img)
	return croped_image
}

func newResizeFuncGift(resampling gift.Resampling) resizeFunc {
	return func(im image.Image) image.Image {
		g := gift.New(gift.Resize(width, height, resampling))
		newIm := newImageFunc(g.Bounds(im.Bounds()))
		g.Draw(newIm, im)
		return newIm
	}
}