aboutsummaryrefslogtreecommitdiff
path: root/vendor/golang.org/x/image/bmp
diff options
context:
space:
mode:
Diffstat (limited to 'vendor/golang.org/x/image/bmp')
-rw-r--r--vendor/golang.org/x/image/bmp/reader.go213
-rw-r--r--vendor/golang.org/x/image/bmp/writer.go262
2 files changed, 0 insertions, 475 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 c10a022..0000000
--- a/vendor/golang.org/x/image/bmp/reader.go
+++ /dev/null
@@ -1,213 +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
- v4InfoHeaderLen = 108
- v5InfoHeaderLen = 124
- )
- var b [1024]byte
- if _, err := io.ReadFull(r, b[:fileHeaderLen+4]); 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])
- infoLen := readUint32(b[14:18])
- if infoLen != infoHeaderLen && infoLen != v4InfoHeaderLen && infoLen != v5InfoHeaderLen {
- return image.Config{}, 0, false, ErrUnsupported
- }
- if _, err := io.ReadFull(r, b[fileHeaderLen+4:fileHeaderLen+infoLen]); err != nil {
- return image.Config{}, 0, false, err
- }
- 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 and 8, 24 or 32 bits per pixel and no
- // compression.
- planes, bpp, compression := readUint16(b[26:28]), readUint16(b[28:30]), readUint32(b[30:34])
- // if compression is set to BITFIELDS, but the bitmask is set to the default bitmask
- // that would be used if compression was set to 0, we can continue as if compression was 0
- if compression == 3 && infoLen > infoHeaderLen &&
- readUint32(b[54:58]) == 0xff0000 && readUint32(b[58:62]) == 0xff00 &&
- readUint32(b[62:66]) == 0xff && readUint32(b[66:70]) == 0xff000000 {
- compression = 0
- }
- if planes != 1 || compression != 0 {
- return image.Config{}, 0, false, ErrUnsupported
- }
- switch bpp {
- case 8:
- if offset != fileHeaderLen+infoLen+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+infoLen {
- return image.Config{}, 0, false, ErrUnsupported
- }
- return image.Config{ColorModel: color.RGBAModel, Width: width, Height: height}, 24, topDown, nil
- case 32:
- if offset != fileHeaderLen+infoLen {
- 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)
-}
diff --git a/vendor/golang.org/x/image/bmp/writer.go b/vendor/golang.org/x/image/bmp/writer.go
deleted file mode 100644
index f07b39d..0000000
--- a/vendor/golang.org/x/image/bmp/writer.go
+++ /dev/null
@@ -1,262 +0,0 @@
-// Copyright 2013 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
-
-import (
- "encoding/binary"
- "errors"
- "image"
- "io"
-)
-
-type header struct {
- sigBM [2]byte
- fileSize uint32
- resverved [2]uint16
- pixOffset uint32
- dibHeaderSize uint32
- width uint32
- height uint32
- colorPlane uint16
- bpp uint16
- compression uint32
- imageSize uint32
- xPixelsPerMeter uint32
- yPixelsPerMeter uint32
- colorUse uint32
- colorImportant uint32
-}
-
-func encodePaletted(w io.Writer, pix []uint8, dx, dy, stride, step int) error {
- var padding []byte
- if dx < step {
- padding = make([]byte, step-dx)
- }
- for y := dy - 1; y >= 0; y-- {
- min := y*stride + 0
- max := y*stride + dx
- if _, err := w.Write(pix[min:max]); err != nil {
- return err
- }
- if padding != nil {
- if _, err := w.Write(padding); err != nil {
- return err
- }
- }
- }
- return nil
-}
-
-func encodeRGBA(w io.Writer, pix []uint8, dx, dy, stride, step int, opaque bool) error {
- buf := make([]byte, step)
- if opaque {
- for y := dy - 1; y >= 0; y-- {
- min := y*stride + 0
- max := y*stride + dx*4
- off := 0
- for i := min; i < max; i += 4 {
- buf[off+2] = pix[i+0]
- buf[off+1] = pix[i+1]
- buf[off+0] = pix[i+2]
- off += 3
- }
- if _, err := w.Write(buf); err != nil {
- return err
- }
- }
- } else {
- for y := dy - 1; y >= 0; y-- {
- min := y*stride + 0
- max := y*stride + dx*4
- off := 0
- for i := min; i < max; i += 4 {
- a := uint32(pix[i+3])
- if a == 0 {
- buf[off+2] = 0
- buf[off+1] = 0
- buf[off+0] = 0
- buf[off+3] = 0
- off += 4
- continue
- } else if a == 0xff {
- buf[off+2] = pix[i+0]
- buf[off+1] = pix[i+1]
- buf[off+0] = pix[i+2]
- buf[off+3] = 0xff
- off += 4
- continue
- }
- buf[off+2] = uint8(((uint32(pix[i+0]) * 0xffff) / a) >> 8)
- buf[off+1] = uint8(((uint32(pix[i+1]) * 0xffff) / a) >> 8)
- buf[off+0] = uint8(((uint32(pix[i+2]) * 0xffff) / a) >> 8)
- buf[off+3] = uint8(a)
- off += 4
- }
- if _, err := w.Write(buf); err != nil {
- return err
- }
- }
- }
- return nil
-}
-
-func encodeNRGBA(w io.Writer, pix []uint8, dx, dy, stride, step int, opaque bool) error {
- buf := make([]byte, step)
- if opaque {
- for y := dy - 1; y >= 0; y-- {
- min := y*stride + 0
- max := y*stride + dx*4
- off := 0
- for i := min; i < max; i += 4 {
- buf[off+2] = pix[i+0]
- buf[off+1] = pix[i+1]
- buf[off+0] = pix[i+2]
- off += 3
- }
- if _, err := w.Write(buf); err != nil {
- return err
- }
- }
- } else {
- for y := dy - 1; y >= 0; y-- {
- min := y*stride + 0
- max := y*stride + dx*4
- off := 0
- for i := min; i < max; i += 4 {
- buf[off+2] = pix[i+0]
- buf[off+1] = pix[i+1]
- buf[off+0] = pix[i+2]
- buf[off+3] = pix[i+3]
- off += 4
- }
- if _, err := w.Write(buf); err != nil {
- return err
- }
- }
- }
- return nil
-}
-
-func encode(w io.Writer, m image.Image, step int) error {
- b := m.Bounds()
- buf := make([]byte, step)
- for y := b.Max.Y - 1; y >= b.Min.Y; y-- {
- off := 0
- for x := b.Min.X; x < b.Max.X; x++ {
- r, g, b, _ := m.At(x, y).RGBA()
- buf[off+2] = byte(r >> 8)
- buf[off+1] = byte(g >> 8)
- buf[off+0] = byte(b >> 8)
- off += 3
- }
- if _, err := w.Write(buf); err != nil {
- return err
- }
- }
- return nil
-}
-
-// Encode writes the image m to w in BMP format.
-func Encode(w io.Writer, m image.Image) error {
- d := m.Bounds().Size()
- if d.X < 0 || d.Y < 0 {
- return errors.New("bmp: negative bounds")
- }
- h := &header{
- sigBM: [2]byte{'B', 'M'},
- fileSize: 14 + 40,
- pixOffset: 14 + 40,
- dibHeaderSize: 40,
- width: uint32(d.X),
- height: uint32(d.Y),
- colorPlane: 1,
- }
-
- var step int
- var palette []byte
- var opaque bool
- switch m := m.(type) {
- case *image.Gray:
- step = (d.X + 3) &^ 3
- palette = make([]byte, 1024)
- for i := 0; i < 256; i++ {
- palette[i*4+0] = uint8(i)
- palette[i*4+1] = uint8(i)
- palette[i*4+2] = uint8(i)
- palette[i*4+3] = 0xFF
- }
- h.imageSize = uint32(d.Y * step)
- h.fileSize += uint32(len(palette)) + h.imageSize
- h.pixOffset += uint32(len(palette))
- h.bpp = 8
-
- case *image.Paletted:
- step = (d.X + 3) &^ 3
- palette = make([]byte, 1024)
- for i := 0; i < len(m.Palette) && i < 256; i++ {
- r, g, b, _ := m.Palette[i].RGBA()
- palette[i*4+0] = uint8(b >> 8)
- palette[i*4+1] = uint8(g >> 8)
- palette[i*4+2] = uint8(r >> 8)
- palette[i*4+3] = 0xFF
- }
- h.imageSize = uint32(d.Y * step)
- h.fileSize += uint32(len(palette)) + h.imageSize
- h.pixOffset += uint32(len(palette))
- h.bpp = 8
- case *image.RGBA:
- opaque = m.Opaque()
- if opaque {
- step = (3*d.X + 3) &^ 3
- h.bpp = 24
- } else {
- step = 4 * d.X
- h.bpp = 32
- }
- h.imageSize = uint32(d.Y * step)
- h.fileSize += h.imageSize
- case *image.NRGBA:
- opaque = m.Opaque()
- if opaque {
- step = (3*d.X + 3) &^ 3
- h.bpp = 24
- } else {
- step = 4 * d.X
- h.bpp = 32
- }
- h.imageSize = uint32(d.Y * step)
- h.fileSize += h.imageSize
- default:
- step = (3*d.X + 3) &^ 3
- h.imageSize = uint32(d.Y * step)
- h.fileSize += h.imageSize
- h.bpp = 24
- }
-
- if err := binary.Write(w, binary.LittleEndian, h); err != nil {
- return err
- }
- if palette != nil {
- if err := binary.Write(w, binary.LittleEndian, palette); err != nil {
- return err
- }
- }
-
- if d.X == 0 || d.Y == 0 {
- return nil
- }
-
- switch m := m.(type) {
- case *image.Gray:
- return encodePaletted(w, m.Pix, d.X, d.Y, m.Stride, step)
- case *image.Paletted:
- return encodePaletted(w, m.Pix, d.X, d.Y, m.Stride, step)
- case *image.RGBA:
- return encodeRGBA(w, m.Pix, d.X, d.Y, m.Stride, step, opaque)
- case *image.NRGBA:
- return encodeNRGBA(w, m.Pix, d.X, d.Y, m.Stride, step, opaque)
- }
- return encode(w, m, step)
-}
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-02 13:54:11 +0000