Golang imaging.FlipV函数代码示例

func CaptureToPng(filename string) error {
	// Based on a version from https://github.com/go-gl/glh.

	// Copyright (c) 2012 The go-gl Authors. All rights reserved.
	w, h := glh.GetViewportWH()

	im := image.NewNRGBA(image.Rect(0, 0, w, h))
	gl.ReadBuffer(gl.BACK_LEFT)
	gl.ReadPixels(0, 0, w, h, gl.RGBA, gl.UNSIGNED_BYTE, im.Pix)

	// Flip the image vertically.
	//
	// From IRC:
	// <ClaudiusMaximus> nictuku: glReadPixels uses (0,0) at bottom left always
	// - some (most?) image formats use (0,0) as top left
	im = imaging.FlipV(im)

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

	png.Encode(fd, im)
	return nil
}

// transformImage modifies the image m based on the transformations specified
// in opt.
func transformImage(m image.Image, opt Options) image.Image {
	// resize if needed
	if w, h, resize := resizeParams(m, opt); resize {
		if opt.Fit {
			m = imaging.Fit(m, w, h, resampleFilter)
		} else {
			if w == 0 || h == 0 {
				m = imaging.Resize(m, w, h, resampleFilter)
			} else {
				m = imaging.Thumbnail(m, w, h, resampleFilter)
			}
		}
	}

	// flip
	if opt.FlipVertical {
		m = imaging.FlipV(m)
	}
	if opt.FlipHorizontal {
		m = imaging.FlipH(m)
	}

	// rotate
	switch opt.Rotate {
	case 90:
		m = imaging.Rotate90(m)
	case 180:
		m = imaging.Rotate180(m)
	case 270:
		m = imaging.Rotate270(m)
	}

	return m
}

func DecodeImage(data io.Reader) (image.Image, error) {
	img, _, err := image.Decode(data)
	if err != nil {
		fmt.Printf("Error decoding geometry file: %v\n", err)
		return nil, err
	}
	img = imaging.FlipV(img)
	return img, nil
}

func (te *TextElement) updateImage(size mgl32.Vec2) {
	// Initialize the context.
	bg := image.Transparent
	c := te.getContext()

	text := te.GetHiddenText()
	if len(text) == 0 {
		text = te.props.placeholder
		r, g, b, _ := te.props.textColor.RGBA()
		placeholderColor := color.RGBA{uint8(r), uint8(g), uint8(b), 80}
		c.SetSrc(image.NewUniform(placeholderColor))
	}

	// Establish image dimensions and do word wrap
	textHeight := c.PointToFixed(float64(te.props.textSize))
	var width int
	var height int = int(textHeight >> 6)
	words := strings.Split(text, " ")
	lines := []string{""}
	lineNb := 0
	for _, word := range words {
		wordWithSpace := fmt.Sprintf("%v ", word)
		dimensions, _ := c.StringDimensions(wordWithSpace)
		width += int(dimensions.X >> 6)
		if width > int(size.X()) {
			width = int(dimensions.X >> 6)
			height += int(dimensions.Y>>6) + 1
			lines = append(lines, "")
			lineNb += 1
		}
		lines[lineNb] = fmt.Sprintf("%v%v", lines[lineNb], wordWithSpace)
	}
	if te.props.height > 0 {
		height = int(te.props.height)
	}

	rgba := image.NewRGBA(image.Rect(0, 0, int(size.X()), height+int(textHeight>>6)/3))
	draw.Draw(rgba, rgba.Bounds(), bg, image.ZP, draw.Src)
	c.SetClip(rgba.Bounds())
	c.SetDst(rgba)

	// Draw the text.
	pt := freetype.Pt(0, int(textHeight>>6))
	for _, line := range lines {
		_, err := c.DrawString(line, pt)
		if err != nil {
			log.Printf("Error drawing string: %v\n", err)
			return
		}
		pt.Y += textHeight
	}

	te.img.SetImage(imaging.FlipV(rgba))
	te.img.SetWidth(float32(rgba.Bounds().Size().X))
	te.img.SetHeight(float32(rgba.Bounds().Size().Y))
}

func (glRenderer *OpenglRenderer) loadCubeMap(right, left, top, bottom, back, front image.Image, textureUnit uint32, lod bool) uint32 {
	var texId uint32
	gl.GenTextures(1, &texId)
	gl.ActiveTexture(textureUnit)
	gl.BindTexture(gl.TEXTURE_CUBE_MAP, texId)

	for i := 0; i < 6; i++ {
		img := right
		var texIndex uint32 = gl.TEXTURE_CUBE_MAP_POSITIVE_X
		switch i {
		case 1:
			img = left
			texIndex = gl.TEXTURE_CUBE_MAP_NEGATIVE_X
		case 2:
			img = top
			texIndex = gl.TEXTURE_CUBE_MAP_NEGATIVE_Y
		case 3:
			img = bottom
			texIndex = gl.TEXTURE_CUBE_MAP_POSITIVE_Y
		case 4:
			img = back
			texIndex = gl.TEXTURE_CUBE_MAP_NEGATIVE_Z
		case 5:
			img = front
			texIndex = gl.TEXTURE_CUBE_MAP_POSITIVE_Z
		}
		img = imaging.FlipV(img)
		rgba := image.NewRGBA(img.Bounds())
		if rgba.Stride != rgba.Rect.Size().X*4 {
			log.Fatal("unsupported stride")
		}
		draw.Draw(rgba, rgba.Bounds(), img, image.Point{0, 0}, draw.Src)
		gl.TexImage2D(
			texIndex,
			0,
			gl.RGBA,
			int32(rgba.Rect.Size().X),
			int32(rgba.Rect.Size().Y),
			0,
			gl.RGBA,
			gl.UNSIGNED_BYTE,
			gl.Ptr(rgba.Pix),
		)
		gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
		gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
		gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)
		gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_WRAP_R, gl.CLAMP_TO_EDGE)
		if lod {
			gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MIN_FILTER, gl.LINEAR_MIPMAP_LINEAR)
			gl.GenerateMipmap(gl.TEXTURE_CUBE_MAP)
		} else {
			gl.TexParameteri(gl.TEXTURE_CUBE_MAP, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
		}
	}
	return texId
}

func rotate(img image.Image, orientation int) image.Image {
	fmt.Println("orientation:", orientation)
	// 1        2       3      4         5            6           7          8

	// 888888  888888      88  88      8888888888  88                  88  8888888888
	// 88          88      88  88      88  88      88  88          88  88      88  88
	// 8888      8888    8888  8888    88          8888888888  8888888888          88
	// 88          88      88  88
	// 88          88  888888  888888

	// func Rotate180(img image.Image) *image.NRGBA
	// func Rotate270(img image.Image) *image.NRGBA
	// func Rotate90(img image.Image) *image.NRGBA
	// func FlipH(img image.Image) *image.NRGBA
	// func FlipV(img image.Image) *image.NRGBA

	var out image.Image
	switch orientation {
	case 1:
		out = img
		// nothing;
	case 2:
		out = imaging.FlipH(img)
		// flip Horiz L to R
	case 3:
		out = imaging.Rotate180(img)
		// rotate 180 ccw
	case 4:
		out = imaging.FlipV(img)
		// flip Vert T to B
	case 5:
		out = imaging.Transpose(img)
		// transpose
	case 6:
		out = imaging.Rotate90(img)
		// rotate 90
	case 7:
		out = imaging.Transverse(img)
		// transverse
	case 8:
		out = imaging.Rotate270(img)
		// rotate 270
	default:
		out = img
		// nothing;
	}

	return out
}

func handleImages(previewPathList []string, thumbnailPathList []string, fileData [][]byte) {
	for i, data := range fileData {
		go func(i int, data []byte) {
			// Decode image bytes into Image object
			img, imgType, err := image.Decode(bytes.NewReader(fileData[i]))
			if err != nil {
				l4g.Error(utils.T("api.file.handle_images_forget.decode.error"), err)
				return
			}

			width := img.Bounds().Dx()
			height := img.Bounds().Dy()

			// Fill in the background of a potentially-transparent png file as white
			if imgType == "png" {
				dst := image.NewRGBA(img.Bounds())
				draw.Draw(dst, dst.Bounds(), image.NewUniform(color.White), image.Point{}, draw.Src)
				draw.Draw(dst, dst.Bounds(), img, img.Bounds().Min, draw.Over)
				img = dst
			}

			// Flip the image to be upright
			orientation, _ := getImageOrientation(fileData[i])

			switch orientation {
			case UprightMirrored:
				img = imaging.FlipH(img)
			case UpsideDown:
				img = imaging.Rotate180(img)
			case UpsideDownMirrored:
				img = imaging.FlipV(img)
			case RotatedCWMirrored:
				img = imaging.Transpose(img)
			case RotatedCCW:
				img = imaging.Rotate270(img)
			case RotatedCCWMirrored:
				img = imaging.Transverse(img)
			case RotatedCW:
				img = imaging.Rotate90(img)
			}

			go generateThumbnailImage(img, thumbnailPathList[i], width, height)
			go generatePreviewImage(img, previewPathList[i], width)
		}(i, data)
	}
}

func prepareImage(fileData []byte) (*image.Image, int, int) {
	// Decode image bytes into Image object
	img, imgType, err := image.Decode(bytes.NewReader(fileData))
	if err != nil {
		l4g.Error(utils.T("api.file.handle_images_forget.decode.error"), err)
		return nil, 0, 0
	}

	width := img.Bounds().Dx()
	height := img.Bounds().Dy()

	// Fill in the background of a potentially-transparent png file as white
	if imgType == "png" {
		dst := image.NewRGBA(img.Bounds())
		draw.Draw(dst, dst.Bounds(), image.NewUniform(color.White), image.Point{}, draw.Src)
		draw.Draw(dst, dst.Bounds(), img, img.Bounds().Min, draw.Over)
		img = dst
	}

	// Flip the image to be upright
	orientation, _ := getImageOrientation(fileData)

	switch orientation {
	case UprightMirrored:
		img = imaging.FlipH(img)
	case UpsideDown:
		img = imaging.Rotate180(img)
	case UpsideDownMirrored:
		img = imaging.FlipV(img)
	case RotatedCWMirrored:
		img = imaging.Transpose(img)
	case RotatedCCW:
		img = imaging.Rotate270(img)
	case RotatedCCWMirrored:
		img = imaging.Transverse(img)
	case RotatedCW:
		img = imaging.Rotate90(img)
	}

	return &img, width, height
}

// Transforms image (resize, rotate, flip, brightness, contrast)
func (c *Convertor) TransformImage(img image.Image) image.Image {
	var i image.Image = img

	if c.Opts.Width > 0 || c.Opts.Height > 0 {
		if c.Opts.Fit {
			i = imaging.Fit(i, c.Opts.Width, c.Opts.Height, filters[c.Opts.Filter])
		} else {
			i = imaging.Resize(i, c.Opts.Width, c.Opts.Height, filters[c.Opts.Filter])
		}
	}

	if c.Opts.Rotate > 0 {
		switch c.Opts.Rotate {
		case 90:
			i = imaging.Rotate90(i)
		case 180:
			i = imaging.Rotate180(i)
		case 270:
			i = imaging.Rotate270(i)
		}
	}

	if c.Opts.Flip != "none" {
		switch c.Opts.Flip {
		case "horizontal":
			i = imaging.FlipH(i)
		case "vertical":
			i = imaging.FlipV(i)
		}
	}

	if c.Opts.Brightness != 0 {
		i = imaging.AdjustBrightness(i, c.Opts.Brightness)
	}

	if c.Opts.Contrast != 0 {
		i = imaging.AdjustContrast(i, c.Opts.Contrast)
	}

	return i
}

func (self *TextureManager) loadTextureFromFile(texturePath string, isMagenta, forceMaxResolution bool) (*image.NRGBA, error) {
	textureFile, err := os.Open(texturePath)
	if err != nil {
		return nil, err
	}
	defer textureFile.Close()
	img, err := png.Decode(textureFile)
	if err != nil {
		return nil, err
	}
	//Bild für OpenGL drehen
	texture := imaging.FlipV(img)
	if !forceMaxResolution {
		//es soll nicht die max. Texturauflösung verwendet werden --> Bild entsprechend halbieren
		for res := 5 - self.resolution; res > 0; res-- {
			size := texture.Bounds().Size()
			texture = imaging.Resize(texture, size.X/2, size.Y/2, imaging.Linear)
		}
	}
	if isMagenta {
		convertImageToAlpha(texture)
	}
	return texture, nil
}

//.........这里部分代码省略.........
	bucketHandle = client.Bucket(bucketName)
	c.Infof("APP Engine Version: %s", gcsappengine.VersionID(cc))
	c.Infof("Using bucket name: %s", bucketName)

	// Change default object ACLs
	if err = bucketHandle.DefaultObjectACL().Set(cc, storage.AllUsers, storage.RoleReader); err != nil {
		c.Errorf("%v in saving default object ACL rule for bucket %q", err, bucketName)
		r = http.StatusInternalServerError
		return
	}

	// Store rotated image in Google Cloud Storage
	var in *bytes.Reader = bytes.NewReader(b)
	var x *exif.Exif = nil
	var orientation *tiff.Tag = nil
	var beforeImage image.Image
	var afterImage *image.NRGBA = nil

	// Read EXIF
	if _, err = in.Seek(0, 0); err != nil {
		c.Errorf("%s in moving the reader offset to the beginning in order to read EXIF", err)
		return
	}
	if x, err = exif.Decode(in); err != nil {
		c.Errorf("%s in decoding JPEG image", err)
		return
	}

	// Get Orientation
	if orientation, err = x.Get(exif.Orientation); err != nil {
		c.Warningf("%s in getting orientation from EXIF", err)
		return
	}
	c.Debugf("Orientation %s", orientation.String())

	// Open image
	if _, err = in.Seek(0, 0); err != nil {
		c.Errorf("%s in moving the reader offset to the beginning in order to read EXIF", err)
		return
	}
	if beforeImage, err = imaging.Decode(in); err != nil {
		c.Errorf("%s in opening image %s", err)
		return
	}

	switch orientation.String() {
	case "1":
		afterImage = beforeImage.(*image.NRGBA)
	case "2":
		afterImage = imaging.FlipH(beforeImage)
	case "3":
		afterImage = imaging.Rotate180(beforeImage)
	case "4":
		afterImage = imaging.FlipV(beforeImage)
	case "5":
		afterImage = imaging.Transverse(beforeImage)
	case "6":
		afterImage = imaging.Rotate270(beforeImage)
	case "7":
		afterImage = imaging.Transpose(beforeImage)
	case "8":
		afterImage = imaging.Rotate90(beforeImage)
	}

	// Save rotated image
	wc = bucketHandle.Object(fileName).NewWriter(cc)
	wc.ContentType = contentType
	if err = imaging.Encode(wc, afterImage, imaging.JPEG); err != nil {
		c.Errorf("%s in saving rotated image", err)
		return
	}
	if err = wc.Close(); err != nil {
		c.Errorf("CreateFile: unable to close bucket %q, file %q: %v", bucketName, fileName, err)
		r = 1
		return
	}
	wc = nil

	// Make thumbnail
	if afterImage.Rect.Dx() > afterImage.Rect.Dy() {
		afterImage = imaging.Resize(afterImage, 1920, 0, imaging.Lanczos)
	} else {
		afterImage = imaging.Resize(afterImage, 0, 1920, imaging.Lanczos)
	}

	// Save thumbnail
	wc = bucketHandle.Object(fileNameThumbnail).NewWriter(cc)
	wc.ContentType = contentType
	if imaging.Encode(wc, afterImage, imaging.JPEG); err != nil {
		c.Errorf("%s in saving image thumbnail", err)
		return
	}
	if err = wc.Close(); err != nil {
		c.Errorf("CreateFileThumbnail: unable to close bucket %q, file %q: %v", bucketName, fileNameThumbnail, err)
		r = 1
		return
	}

	c.Infof("/%v/%v, /%v/%v created", bucketName, fileName, bucketName, fileNameThumbnail)
}

// transformImage modifies the image m based on the transformations specified
// in opt.
func transformImage(m image.Image, opt Options) image.Image {
	// convert percentage width and height values to absolute values
	imgW := m.Bounds().Max.X - m.Bounds().Min.X
	imgH := m.Bounds().Max.Y - m.Bounds().Min.Y
	var w, h int
	if 0 < opt.Width && opt.Width < 1 {
		w = int(float64(imgW) * opt.Width)
	} else if opt.Width < 0 {
		w = 0
	} else {
		w = int(opt.Width)
	}
	if 0 < opt.Height && opt.Height < 1 {
		h = int(float64(imgH) * opt.Height)
	} else if opt.Height < 0 {
		h = 0
	} else {
		h = int(opt.Height)
	}

	// never resize larger than the original image
	if !opt.ScaleUp {
		if w > imgW {
			w = imgW
		}
		if h > imgH {
			h = imgH
		}
	}

	// resize
	if w != 0 || h != 0 {
		if opt.Fit {
			m = imaging.Fit(m, w, h, resampleFilter)
		} else {
			if w == 0 || h == 0 {
				m = imaging.Resize(m, w, h, resampleFilter)
			} else {
				m = imaging.Thumbnail(m, w, h, resampleFilter)
			}
		}
	}

	// flip
	if opt.FlipVertical {
		m = imaging.FlipV(m)
	}
	if opt.FlipHorizontal {
		m = imaging.FlipH(m)
	}

	// rotate
	switch opt.Rotate {
	case 90:
		m = imaging.Rotate90(m)
	case 180:
		m = imaging.Rotate180(m)
	case 270:
		m = imaging.Rotate270(m)
	}

	return m
}

func (i imagingFlipper) FlipVertical(tile image.Image) image.Image {
	return imaging.FlipV(tile)
}

func main() {
	fmt.Println("Hello, world")
	fname := "P1070332.JPG"
	rname := "P1070332_rotate.JPG"
	sname := "P1070332_small.JPG"

	f, err := os.Open(fname)
	if err != nil {
		log.Fatal(err)
	}
	defer f.Close()

	// Optionally register camera makenote data parsing - currently Nikon and
	// Canon are supported.
	exif.RegisterParsers(mknote.All...)

	x, err := exif.Decode(f)
	if err != nil {
		log.Fatal(err)
	}

	// Get Orientation
	orientation, err := x.Get(exif.Orientation)
	if err != nil {
		fmt.Println(exif.Model, " not fround")
		return
	}
	fmt.Println("Orientation", orientation.String())

	// Rotate
	var rotateImage *image.NRGBA
	openImage, err := imaging.Open(fname)
	if err != nil {
		fmt.Println(err)
		return
	}
	switch orientation.String() {
	case "1":
	// Do nothing
	case "2":
		rotateImage = imaging.FlipH(openImage)
	case "3":
		rotateImage = imaging.Rotate180(openImage)
	case "4":
		rotateImage = imaging.FlipV(openImage)
	case "5":
		rotateImage = imaging.Transverse(openImage)
	case "6":
		rotateImage = imaging.Rotate270(openImage)
	case "7":
		rotateImage = imaging.Transpose(openImage)
	case "8":
		rotateImage = imaging.Rotate90(openImage)
	}
	err = imaging.Save(rotateImage, rname)
	if err != nil {
		fmt.Println(err)
		return
	}
	fmt.Println(rname, " saved")

	// Small
	var smallImage *image.NRGBA
	if rotateImage.Rect.Dx() > rotateImage.Rect.Dy() {
		smallImage = imaging.Resize(rotateImage, 1920, 0, imaging.Lanczos)
	} else {
		smallImage = imaging.Resize(rotateImage, 0, 1920, imaging.Lanczos)
	}
	err = imaging.Save(smallImage, sname)
	if err != nil {
		fmt.Println(err)
		return
	}
	fmt.Println(sname, " saved")

	// Use jpeg.Encode() to write to a file
	// https://github.com/disintegration/imaging/blob/master/helpers.go#L79
	// func Encode(w io.Writer, m image.Image, o *Options) error
	// https://golang.org/pkg/image/jpeg/
}