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authorDimitri Sokolyuk <demon@dim13.org>2018-09-27 20:03:23 +0200
committerDimitri Sokolyuk <demon@dim13.org>2018-09-27 20:03:23 +0200
commit14bb08c1df8db9ec6c8a05520d4eee67971235d9 (patch)
treefc820e59c26ed4c5e87e65737909b47959f0faa5 /vendor/golang.org/x/image/bmp/reader.go
parent54eb169e8fc9bc0357139e7c259e977b184f8fbb (diff)
mod tidy
Diffstat (limited to 'vendor/golang.org/x/image/bmp/reader.go')
-rw-r--r--vendor/golang.org/x/image/bmp/reader.go199
1 files changed, 0 insertions, 199 deletions
diff --git a/vendor/golang.org/x/image/bmp/reader.go b/vendor/golang.org/x/image/bmp/reader.go
deleted file mode 100644
index a0f2715..0000000
--- a/vendor/golang.org/x/image/bmp/reader.go
+++ /dev/null
@@ -1,199 +0,0 @@
-// Copyright 2011 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 bmp implements a BMP image decoder and encoder.
-//
-// The BMP specification is at http://www.digicamsoft.com/bmp/bmp.html.
-package bmp // import "golang.org/x/image/bmp"
-
-import (
- "errors"
- "image"
- "image/color"
- "io"
-)
-
-// ErrUnsupported means that the input BMP image uses a valid but unsupported
-// feature.
-var ErrUnsupported = errors.New("bmp: unsupported BMP image")
-
-func readUint16(b []byte) uint16 {
- return uint16(b[0]) | uint16(b[1])<<8
-}
-
-func readUint32(b []byte) uint32 {
- return uint32(b[0]) | uint32(b[1])<<8 | uint32(b[2])<<16 | uint32(b[3])<<24
-}
-
-// decodePaletted reads an 8 bit-per-pixel BMP image from r.
-// If topDown is false, the image rows will be read bottom-up.
-func decodePaletted(r io.Reader, c image.Config, topDown bool) (image.Image, error) {
- paletted := image.NewPaletted(image.Rect(0, 0, c.Width, c.Height), c.ColorModel.(color.Palette))
- if c.Width == 0 || c.Height == 0 {
- return paletted, nil
- }
- var tmp [4]byte
- y0, y1, yDelta := c.Height-1, -1, -1
- if topDown {
- y0, y1, yDelta = 0, c.Height, +1
- }
- for y := y0; y != y1; y += yDelta {
- p := paletted.Pix[y*paletted.Stride : y*paletted.Stride+c.Width]
- if _, err := io.ReadFull(r, p); err != nil {
- return nil, err
- }
- // Each row is 4-byte aligned.
- if c.Width%4 != 0 {
- _, err := io.ReadFull(r, tmp[:4-c.Width%4])
- if err != nil {
- return nil, err
- }
- }
- }
- return paletted, nil
-}
-
-// decodeRGB reads a 24 bit-per-pixel BMP image from r.
-// If topDown is false, the image rows will be read bottom-up.
-func decodeRGB(r io.Reader, c image.Config, topDown bool) (image.Image, error) {
- rgba := image.NewRGBA(image.Rect(0, 0, c.Width, c.Height))
- if c.Width == 0 || c.Height == 0 {
- return rgba, nil
- }
- // There are 3 bytes per pixel, and each row is 4-byte aligned.
- b := make([]byte, (3*c.Width+3)&^3)
- y0, y1, yDelta := c.Height-1, -1, -1
- if topDown {
- y0, y1, yDelta = 0, c.Height, +1
- }
- for y := y0; y != y1; y += yDelta {
- if _, err := io.ReadFull(r, b); err != nil {
- return nil, err
- }
- p := rgba.Pix[y*rgba.Stride : y*rgba.Stride+c.Width*4]
- for i, j := 0, 0; i < len(p); i, j = i+4, j+3 {
- // BMP images are stored in BGR order rather than RGB order.
- p[i+0] = b[j+2]
- p[i+1] = b[j+1]
- p[i+2] = b[j+0]
- p[i+3] = 0xFF
- }
- }
- return rgba, nil
-}
-
-// decodeNRGBA reads a 32 bit-per-pixel BMP image from r.
-// If topDown is false, the image rows will be read bottom-up.
-func decodeNRGBA(r io.Reader, c image.Config, topDown bool) (image.Image, error) {
- rgba := image.NewNRGBA(image.Rect(0, 0, c.Width, c.Height))
- if c.Width == 0 || c.Height == 0 {
- return rgba, nil
- }
- y0, y1, yDelta := c.Height-1, -1, -1
- if topDown {
- y0, y1, yDelta = 0, c.Height, +1
- }
- for y := y0; y != y1; y += yDelta {
- p := rgba.Pix[y*rgba.Stride : y*rgba.Stride+c.Width*4]
- if _, err := io.ReadFull(r, p); err != nil {
- return nil, err
- }
- for i := 0; i < len(p); i += 4 {
- // BMP images are stored in BGRA order rather than RGBA order.
- p[i+0], p[i+2] = p[i+2], p[i+0]
- }
- }
- return rgba, nil
-}
-
-// Decode reads a BMP image from r and returns it as an image.Image.
-// Limitation: The file must be 8, 24 or 32 bits per pixel.
-func Decode(r io.Reader) (image.Image, error) {
- c, bpp, topDown, err := decodeConfig(r)
- if err != nil {
- return nil, err
- }
- switch bpp {
- case 8:
- return decodePaletted(r, c, topDown)
- case 24:
- return decodeRGB(r, c, topDown)
- case 32:
- return decodeNRGBA(r, c, topDown)
- }
- panic("unreachable")
-}
-
-// DecodeConfig returns the color model and dimensions of a BMP image without
-// decoding the entire image.
-// Limitation: The file must be 8, 24 or 32 bits per pixel.
-func DecodeConfig(r io.Reader) (image.Config, error) {
- config, _, _, err := decodeConfig(r)
- return config, err
-}
-
-func decodeConfig(r io.Reader) (config image.Config, bitsPerPixel int, topDown bool, err error) {
- // We only support those BMP images that are a BITMAPFILEHEADER
- // immediately followed by a BITMAPINFOHEADER.
- const (
- fileHeaderLen = 14
- infoHeaderLen = 40
- )
- var b [1024]byte
- if _, err := io.ReadFull(r, b[:fileHeaderLen+infoHeaderLen]); err != nil {
- return image.Config{}, 0, false, err
- }
- if string(b[:2]) != "BM" {
- return image.Config{}, 0, false, errors.New("bmp: invalid format")
- }
- offset := readUint32(b[10:14])
- if readUint32(b[14:18]) != infoHeaderLen {
- return image.Config{}, 0, false, ErrUnsupported
- }
- width := int(int32(readUint32(b[18:22])))
- height := int(int32(readUint32(b[22:26])))
- if height < 0 {
- height, topDown = -height, true
- }
- if width < 0 || height < 0 {
- return image.Config{}, 0, false, ErrUnsupported
- }
- // We only support 1 plane, 8 or 24 bits per pixel and no compression.
- planes, bpp, compression := readUint16(b[26:28]), readUint16(b[28:30]), readUint32(b[30:34])
- if planes != 1 || compression != 0 {
- return image.Config{}, 0, false, ErrUnsupported
- }
- switch bpp {
- case 8:
- if offset != fileHeaderLen+infoHeaderLen+256*4 {
- return image.Config{}, 0, false, ErrUnsupported
- }
- _, err = io.ReadFull(r, b[:256*4])
- if err != nil {
- return image.Config{}, 0, false, err
- }
- pcm := make(color.Palette, 256)
- for i := range pcm {
- // BMP images are stored in BGR order rather than RGB order.
- // Every 4th byte is padding.
- pcm[i] = color.RGBA{b[4*i+2], b[4*i+1], b[4*i+0], 0xFF}
- }
- return image.Config{ColorModel: pcm, Width: width, Height: height}, 8, topDown, nil
- case 24:
- if offset != fileHeaderLen+infoHeaderLen {
- return image.Config{}, 0, false, ErrUnsupported
- }
- return image.Config{ColorModel: color.RGBAModel, Width: width, Height: height}, 24, topDown, nil
- case 32:
- if offset != fileHeaderLen+infoHeaderLen {
- return image.Config{}, 0, false, ErrUnsupported
- }
- return image.Config{ColorModel: color.RGBAModel, Width: width, Height: height}, 32, topDown, nil
- }
- return image.Config{}, 0, false, ErrUnsupported
-}
-
-func init() {
- image.RegisterFormat("bmp", "BM????\x00\x00\x00\x00", Decode, DecodeConfig)
-}