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Diffstat (limited to 'vendor/golang.org/x/image/webp/nycbcra/nycbcra.go')
-rw-r--r--vendor/golang.org/x/image/webp/nycbcra/nycbcra.go194
1 files changed, 0 insertions, 194 deletions
diff --git a/vendor/golang.org/x/image/webp/nycbcra/nycbcra.go b/vendor/golang.org/x/image/webp/nycbcra/nycbcra.go
deleted file mode 100644
index 101c41f..0000000
--- a/vendor/golang.org/x/image/webp/nycbcra/nycbcra.go
+++ /dev/null
@@ -1,194 +0,0 @@
-// Copyright 2014 The Go Authors. All rights reserved.
-// Use of this source code is governed by a BSD-style
-// license that can be found in the LICENSE file.
-
-// Package nycbcra provides non-alpha-premultiplied Y'CbCr-with-alpha image and
-// color types.
-//
-// Deprecated: as of Go 1.6. Use the standard image and image/color packages
-// instead.
-package nycbcra // import "golang.org/x/image/webp/nycbcra"
-
-import (
- "image"
- "image/color"
-)
-
-func init() {
- println("The golang.org/x/image/webp/nycbcra package is deprecated, as of Go 1.6. " +
- "Use the standard image and image/color packages instead.")
-}
-
-// TODO: move this to the standard image and image/color packages, so that the
-// image/draw package can have fast-path code. Moving would rename:
-// nycbcra.Color to color.NYCbCrA
-// nycbcra.ColorModel to color.NYCbCrAModel
-// nycbcra.Image to image.NYCbCrA
-
-// Color represents a non-alpha-premultiplied Y'CbCr-with-alpha color, having
-// 8 bits each for one luma, two chroma and one alpha component.
-type Color struct {
- color.YCbCr
- A uint8
-}
-
-func (c Color) RGBA() (r, g, b, a uint32) {
- r8, g8, b8 := color.YCbCrToRGB(c.Y, c.Cb, c.Cr)
- a = uint32(c.A) * 0x101
- r = uint32(r8) * 0x101 * a / 0xffff
- g = uint32(g8) * 0x101 * a / 0xffff
- b = uint32(b8) * 0x101 * a / 0xffff
- return
-}
-
-// ColorModel is the Model for non-alpha-premultiplied Y'CbCr-with-alpha colors.
-var ColorModel color.Model = color.ModelFunc(nYCbCrAModel)
-
-func nYCbCrAModel(c color.Color) color.Color {
- switch c := c.(type) {
- case Color:
- return c
- case color.YCbCr:
- return Color{c, 0xff}
- }
- r, g, b, a := c.RGBA()
-
- // Convert from alpha-premultiplied to non-alpha-premultiplied.
- if a != 0 {
- r = (r * 0xffff) / a
- g = (g * 0xffff) / a
- b = (b * 0xffff) / a
- }
-
- y, u, v := color.RGBToYCbCr(uint8(r>>8), uint8(g>>8), uint8(b>>8))
- return Color{color.YCbCr{Y: y, Cb: u, Cr: v}, uint8(a >> 8)}
-}
-
-// Image is an in-memory image of non-alpha-premultiplied Y'CbCr-with-alpha
-// colors. A and AStride are analogous to the Y and YStride fields of the
-// embedded YCbCr.
-type Image struct {
- image.YCbCr
- A []uint8
- AStride int
-}
-
-func (p *Image) ColorModel() color.Model {
- return ColorModel
-}
-
-func (p *Image) At(x, y int) color.Color {
- return p.NYCbCrAAt(x, y)
-}
-
-func (p *Image) NYCbCrAAt(x, y int) Color {
- if !(image.Point{X: x, Y: y}.In(p.Rect)) {
- return Color{}
- }
- yi := p.YOffset(x, y)
- ci := p.COffset(x, y)
- ai := p.AOffset(x, y)
- return Color{
- color.YCbCr{
- Y: p.Y[yi],
- Cb: p.Cb[ci],
- Cr: p.Cr[ci],
- },
- p.A[ai],
- }
-}
-
-// AOffset returns the index of the first element of A that corresponds to
-// the pixel at (x, y).
-func (p *Image) AOffset(x, y int) int {
- return (y-p.Rect.Min.Y)*p.AStride + (x - p.Rect.Min.X)
-}
-
-// SubImage returns an image representing the portion of the image p visible
-// through r. The returned value shares pixels with the original image.
-func (p *Image) SubImage(r image.Rectangle) image.Image {
- // TODO: share code with image.NewYCbCr when this type moves into the
- // standard image package.
- r = r.Intersect(p.Rect)
- // If r1 and r2 are Rectangles, r1.Intersect(r2) is not guaranteed to be inside
- // either r1 or r2 if the intersection is empty. Without explicitly checking for
- // this, the Pix[i:] expression below can panic.
- if r.Empty() {
- return &Image{
- YCbCr: image.YCbCr{
- SubsampleRatio: p.SubsampleRatio,
- },
- }
- }
- yi := p.YOffset(r.Min.X, r.Min.Y)
- ci := p.COffset(r.Min.X, r.Min.Y)
- ai := p.AOffset(r.Min.X, r.Min.Y)
- return &Image{
- YCbCr: image.YCbCr{
- Y: p.Y[yi:],
- Cb: p.Cb[ci:],
- Cr: p.Cr[ci:],
- SubsampleRatio: p.SubsampleRatio,
- YStride: p.YStride,
- CStride: p.CStride,
- Rect: r,
- },
- A: p.A[ai:],
- AStride: p.AStride,
- }
-}
-
-// Opaque scans the entire image and reports whether it is fully opaque.
-func (p *Image) Opaque() bool {
- if p.Rect.Empty() {
- return true
- }
- i0, i1 := 0, p.Rect.Dx()
- for y := p.Rect.Min.Y; y < p.Rect.Max.Y; y++ {
- for _, a := range p.A[i0:i1] {
- if a != 0xff {
- return false
- }
- }
- i0 += p.AStride
- i1 += p.AStride
- }
- return true
-}
-
-// New returns a new Image with the given bounds and subsample ratio.
-func New(r image.Rectangle, subsampleRatio image.YCbCrSubsampleRatio) *Image {
- // TODO: share code with image.NewYCbCr when this type moves into the
- // standard image package.
- w, h, cw, ch := r.Dx(), r.Dy(), 0, 0
- switch subsampleRatio {
- case image.YCbCrSubsampleRatio422:
- cw = (r.Max.X+1)/2 - r.Min.X/2
- ch = h
- case image.YCbCrSubsampleRatio420:
- cw = (r.Max.X+1)/2 - r.Min.X/2
- ch = (r.Max.Y+1)/2 - r.Min.Y/2
- case image.YCbCrSubsampleRatio440:
- cw = w
- ch = (r.Max.Y+1)/2 - r.Min.Y/2
- default:
- // Default to 4:4:4 subsampling.
- cw = w
- ch = h
- }
- b := make([]byte, 2*w*h+2*cw*ch)
- // TODO: use s[i:j:k] notation to set the cap.
- return &Image{
- YCbCr: image.YCbCr{
- Y: b[:w*h],
- Cb: b[w*h+0*cw*ch : w*h+1*cw*ch],
- Cr: b[w*h+1*cw*ch : w*h+2*cw*ch],
- SubsampleRatio: subsampleRatio,
- YStride: w,
- CStride: cw,
- Rect: r,
- },
- A: b[w*h+2*cw*ch:],
- AStride: w,
- }
-}