From 4f20ebead36876a88391bf033d1de3e4cf0228da Mon Sep 17 00:00:00 2001 From: Wim Date: Thu, 31 Dec 2020 14:48:12 +0100 Subject: Update vendor for next release (#1343) --- vendor/golang.org/x/image/bmp/reader.go | 219 ++++++ vendor/golang.org/x/image/bmp/writer.go | 262 ++++++++ vendor/golang.org/x/image/ccitt/reader.go | 795 ++++++++++++++++++++++ vendor/golang.org/x/image/ccitt/table.go | 972 +++++++++++++++++++++++++++ vendor/golang.org/x/image/ccitt/writer.go | 102 +++ vendor/golang.org/x/image/tiff/buffer.go | 69 ++ vendor/golang.org/x/image/tiff/compress.go | 58 ++ vendor/golang.org/x/image/tiff/consts.go | 149 ++++ vendor/golang.org/x/image/tiff/fuzz.go | 29 + vendor/golang.org/x/image/tiff/lzw/reader.go | 272 ++++++++ vendor/golang.org/x/image/tiff/reader.go | 709 +++++++++++++++++++ vendor/golang.org/x/image/tiff/writer.go | 438 ++++++++++++ 12 files changed, 4074 insertions(+) create mode 100644 vendor/golang.org/x/image/bmp/reader.go create mode 100644 vendor/golang.org/x/image/bmp/writer.go create mode 100644 vendor/golang.org/x/image/ccitt/reader.go create mode 100644 vendor/golang.org/x/image/ccitt/table.go create mode 100644 vendor/golang.org/x/image/ccitt/writer.go create mode 100644 vendor/golang.org/x/image/tiff/buffer.go create mode 100644 vendor/golang.org/x/image/tiff/compress.go create mode 100644 vendor/golang.org/x/image/tiff/consts.go create mode 100644 vendor/golang.org/x/image/tiff/fuzz.go create mode 100644 vendor/golang.org/x/image/tiff/lzw/reader.go create mode 100644 vendor/golang.org/x/image/tiff/reader.go create mode 100644 vendor/golang.org/x/image/tiff/writer.go (limited to 'vendor/golang.org/x/image') diff --git a/vendor/golang.org/x/image/bmp/reader.go b/vendor/golang.org/x/image/bmp/reader.go new file mode 100644 index 00000000..52e25205 --- /dev/null +++ b/vendor/golang.org/x/image/bmp/reader.go @@ -0,0 +1,219 @@ +// 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 { + if err == io.EOF { + err = io.ErrUnexpectedEOF + } + 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 { + if err == io.EOF { + err = io.ErrUnexpectedEOF + } + 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 new file mode 100644 index 00000000..f07b39db --- /dev/null +++ b/vendor/golang.org/x/image/bmp/writer.go @@ -0,0 +1,262 @@ +// 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) +} diff --git a/vendor/golang.org/x/image/ccitt/reader.go b/vendor/golang.org/x/image/ccitt/reader.go new file mode 100644 index 00000000..340de053 --- /dev/null +++ b/vendor/golang.org/x/image/ccitt/reader.go @@ -0,0 +1,795 @@ +// Copyright 2019 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. + +//go:generate go run gen.go + +// Package ccitt implements a CCITT (fax) image decoder. +package ccitt + +import ( + "encoding/binary" + "errors" + "image" + "io" + "math/bits" +) + +var ( + errIncompleteCode = errors.New("ccitt: incomplete code") + errInvalidBounds = errors.New("ccitt: invalid bounds") + errInvalidCode = errors.New("ccitt: invalid code") + errInvalidMode = errors.New("ccitt: invalid mode") + errInvalidOffset = errors.New("ccitt: invalid offset") + errMissingEOL = errors.New("ccitt: missing End-of-Line") + errRunLengthOverflowsWidth = errors.New("ccitt: run length overflows width") + errRunLengthTooLong = errors.New("ccitt: run length too long") + errUnsupportedMode = errors.New("ccitt: unsupported mode") + errUnsupportedSubFormat = errors.New("ccitt: unsupported sub-format") + errUnsupportedWidth = errors.New("ccitt: unsupported width") +) + +// Order specifies the bit ordering in a CCITT data stream. +type Order uint32 + +const ( + // LSB means Least Significant Bits first. + LSB Order = iota + // MSB means Most Significant Bits first. + MSB +) + +// SubFormat represents that the CCITT format consists of a number of +// sub-formats. Decoding or encoding a CCITT data stream requires knowing the +// sub-format context. It is not represented in the data stream per se. +type SubFormat uint32 + +const ( + Group3 SubFormat = iota + Group4 +) + +// AutoDetectHeight is passed as the height argument to NewReader to indicate +// that the image height (the number of rows) is not known in advance. +const AutoDetectHeight = -1 + +// Options are optional parameters. +type Options struct { + // Align means that some variable-bit-width codes are byte-aligned. + Align bool + // Invert means that black is the 1 bit or 0xFF byte, and white is 0. + Invert bool +} + +// maxWidth is the maximum (inclusive) supported width. This is a limitation of +// this implementation, to guard against integer overflow, and not anything +// inherent to the CCITT format. +const maxWidth = 1 << 20 + +func invertBytes(b []byte) { + for i, c := range b { + b[i] = ^c + } +} + +func reverseBitsWithinBytes(b []byte) { + for i, c := range b { + b[i] = bits.Reverse8(c) + } +} + +// highBits writes to dst (1 bit per pixel, most significant bit first) the +// high (0x80) bits from src (1 byte per pixel). It returns the number of bytes +// written and read such that dst[:d] is the packed form of src[:s]. +// +// For example, if src starts with the 8 bytes [0x7D, 0x7E, 0x7F, 0x80, 0x81, +// 0x82, 0x00, 0xFF] then 0x1D will be written to dst[0]. +// +// If src has (8 * len(dst)) or more bytes then only len(dst) bytes are +// written, (8 * len(dst)) bytes are read, and invert is ignored. +// +// Otherwise, if len(src) is not a multiple of 8 then the final byte written to +// dst is padded with 1 bits (if invert is true) or 0 bits. If inverted, the 1s +// are typically temporary, e.g. they will be flipped back to 0s by an +// invertBytes call in the highBits caller, reader.Read. +func highBits(dst []byte, src []byte, invert bool) (d int, s int) { + // Pack as many complete groups of 8 src bytes as we can. + n := len(src) / 8 + if n > len(dst) { + n = len(dst) + } + dstN := dst[:n] + for i := range dstN { + src8 := src[i*8 : i*8+8] + dstN[i] = ((src8[0] & 0x80) >> 0) | + ((src8[1] & 0x80) >> 1) | + ((src8[2] & 0x80) >> 2) | + ((src8[3] & 0x80) >> 3) | + ((src8[4] & 0x80) >> 4) | + ((src8[5] & 0x80) >> 5) | + ((src8[6] & 0x80) >> 6) | + ((src8[7] & 0x80) >> 7) + } + d, s = n, 8*n + dst, src = dst[d:], src[s:] + + // Pack up to 7 remaining src bytes, if there's room in dst. + if (len(dst) > 0) && (len(src) > 0) { + dstByte := byte(0) + if invert { + dstByte = 0xFF >> uint(len(src)) + } + for n, srcByte := range src { + dstByte |= (srcByte & 0x80) >> uint(n) + } + dst[0] = dstByte + d, s = d+1, s+len(src) + } + return d, s +} + +type bitReader struct { + r io.Reader + + // readErr is the error returned from the most recent r.Read call. As the + // io.Reader documentation says, when r.Read returns (n, err), "always + // process the n > 0 bytes returned before considering the error err". + readErr error + + // order is whether to process r's bytes LSB first or MSB first. + order Order + + // The high nBits bits of the bits field hold upcoming bits in MSB order. + bits uint64 + nBits uint32 + + // bytes[br:bw] holds bytes read from r but not yet loaded into bits. + br uint32 + bw uint32 + bytes [1024]uint8 +} + +func (b *bitReader) alignToByteBoundary() { + n := b.nBits & 7 + b.bits <<= n + b.nBits -= n +} + +// nextBitMaxNBits is the maximum possible value of bitReader.nBits after a +// bitReader.nextBit call, provided that bitReader.nBits was not more than this +// value before that call. +// +// Note that the decode function can unread bits, which can temporarily set the +// bitReader.nBits value above nextBitMaxNBits. +const nextBitMaxNBits = 31 + +func (b *bitReader) nextBit() (uint64, error) { + for { + if b.nBits > 0 { + bit := b.bits >> 63 + b.bits <<= 1 + b.nBits-- + return bit, nil + } + + if available := b.bw - b.br; available >= 4 { + // Read 32 bits, even though b.bits is a uint64, since the decode + // function may need to unread up to maxCodeLength bits, putting + // them back in the remaining (64 - 32) bits. TestMaxCodeLength + // checks that the generated maxCodeLength constant fits. + // + // If changing the Uint32 call, also change nextBitMaxNBits. + b.bits = uint64(binary.BigEndian.Uint32(b.bytes[b.br:])) << 32 + b.br += 4 + b.nBits = 32 + continue + } else if available > 0 { + b.bits = uint64(b.bytes[b.br]) << (7 * 8) + b.br++ + b.nBits = 8 + continue + } + + if b.readErr != nil { + return 0, b.readErr + } + + n, err := b.r.Read(b.bytes[:]) + b.br = 0 + b.bw = uint32(n) + b.readErr = err + + if b.order != MSB { + reverseBitsWithinBytes(b.bytes[:b.bw]) + } + } +} + +func decode(b *bitReader, decodeTable [][2]int16) (uint32, error) { + nBitsRead, bitsRead, state := uint32(0), uint64(0), int32(1) + for { + bit, err := b.nextBit() + if err != nil { + if err == io.EOF { + err = errIncompleteCode + } + return 0, err + } + bitsRead |= bit << (63 - nBitsRead) + nBitsRead++ + + // The "&1" is redundant, but can eliminate a bounds check. + state = int32(decodeTable[state][bit&1]) + if state < 0 { + return uint32(^state), nil + } else if state == 0 { + // Unread the bits we've read, then return errInvalidCode. + b.bits = (b.bits >> nBitsRead) | bitsRead + b.nBits += nBitsRead + return 0, errInvalidCode + } + } +} + +// decodeEOL decodes the 12-bit EOL code 0000_0000_0001. +func decodeEOL(b *bitReader) error { + nBitsRead, bitsRead := uint32(0), uint64(0) + for { + bit, err := b.nextBit() + if err != nil { + if err == io.EOF { + err = errMissingEOL + } + return err + } + bitsRead |= bit << (63 - nBitsRead) + nBitsRead++ + + if nBitsRead < 12 { + if bit&1 == 0 { + continue + } + } else if bit&1 != 0 { + return nil + } + + // Unread the bits we've read, then return errMissingEOL. + b.bits = (b.bits >> nBitsRead) | bitsRead + b.nBits += nBitsRead + return errMissingEOL + } +} + +type reader struct { + br bitReader + subFormat SubFormat + + // width is the image width in pixels. + width int + + // rowsRemaining starts at the image height in pixels, when the reader is + // driven through the io.Reader interface, and decrements to zero as rows + // are decoded. Alternatively, it may be negative if the image height is + // not known in advance at the time of the NewReader call. + // + // When driven through DecodeIntoGray, this field is unused. + rowsRemaining int + + // curr and prev hold the current and previous rows. Each element is either + // 0x00 (black) or 0xFF (white). + // + // prev may be nil, when processing the first row. + curr []byte + prev []byte + + // ri is the read index. curr[:ri] are those bytes of curr that have been + // passed along via the Read method. + // + // When the reader is driven through DecodeIntoGray, instead of through the + // io.Reader interface, this field is unused. + ri int + + // wi is the write index. curr[:wi] are those bytes of curr that have + // already been decoded via the decodeRow method. + // + // What this implementation calls wi is roughly equivalent to what the spec + // calls the a0 index. + wi int + + // These fields are copied from the *Options (which may be nil). + align bool + invert bool + + // atStartOfRow is whether we have just started the row. Some parts of the + // spec say to treat this situation as if "wi = -1". + atStartOfRow bool + + // penColorIsWhite is whether the next run is black or white. + penColorIsWhite bool + + // seenStartOfImage is whether we've called the startDecode method. + seenStartOfImage bool + + // truncated is whether the input is missing the final 6 consecutive EOL's + // (for Group3) or 2 consecutive EOL's (for Group4). Omitting that trailer + // (but otherwise padding to a byte boundary, with either all 0 bits or all + // 1 bits) is invalid according to the spec, but happens in practice when + // exporting from Adobe Acrobat to TIFF + CCITT. This package silently + // ignores the format error for CCITT input that has been truncated in that + // fashion, returning the full decoded image. + // + // Detecting trailer truncation (just after the final row of pixels) + // requires knowing which row is the final row, and therefore does not + // trigger if the image height is not known in advance. + truncated bool + + // readErr is a sticky error for the Read method. + readErr error +} + +func (z *reader) Read(p []byte) (int, error) { + if z.readErr != nil { + return 0, z.readErr + } + originalP := p + + for len(p) > 0 { + // Allocate buffers (and decode any start-of-image codes), if + // processing the first or second row. + if z.curr == nil { + if !z.seenStartOfImage { + if z.readErr = z.startDecode(); z.readErr != nil { + break + } + z.atStartOfRow = true + } + z.curr = make([]byte, z.width) + } + + // Decode the next row, if necessary. + if z.atStartOfRow { + if z.rowsRemaining < 0 { + // We do not know the image height in advance. See if the next + // code is an EOL. If it is, it is consumed. If it isn't, the + // bitReader shouldn't advance along the bit stream, and we + // simply decode another row of pixel data. + // + // For the Group4 subFormat, we may need to align to a byte + // boundary. For the Group3 subFormat, the previous z.decodeRow + // call (or z.startDecode call) has already consumed one of the + // 6 consecutive EOL's. The next EOL is actually the second of + // 6, in the middle, and we shouldn't align at that point. + if z.align && (z.subFormat == Group4) { + z.br.alignToByteBoundary() + } + + if err := z.decodeEOL(); err == errMissingEOL { + // No-op. It's another row of pixel data. + } else if err != nil { + z.readErr = err + break + } else { + if z.readErr = z.finishDecode(true); z.readErr != nil { + break + } + z.readErr = io.EOF + break + } + + } else if z.rowsRemaining == 0 { + // We do know the image height in advance, and we have already + // decoded exactly that many rows. + if z.readErr = z.finishDecode(false); z.readErr != nil { + break + } + z.readErr = io.EOF + break + + } else { + z.rowsRemaining-- + } + + if z.readErr = z.decodeRow(z.rowsRemaining == 0); z.readErr != nil { + break + } + } + + // Pack from z.curr (1 byte per pixel) to p (1 bit per pixel). + packD, packS := highBits(p, z.curr[z.ri:], z.invert) + p = p[packD:] + z.ri += packS + + // Prepare to decode the next row, if necessary. + if z.ri == len(z.curr) { + z.ri, z.curr, z.prev = 0, z.prev, z.curr + z.atStartOfRow = true + } + } + + n := len(originalP) - len(p) + if z.invert { + invertBytes(originalP[:n]) + } + return n, z.readErr +} + +func (z *reader) penColor() byte { + if z.penColorIsWhite { + return 0xFF + } + return 0x00 +} + +func (z *reader) startDecode() error { + switch z.subFormat { + case Group3: + if err := z.decodeEOL(); err != nil { + return err + } + + case Group4: + // No-op. + + default: + return errUnsupportedSubFormat + } + + z.seenStartOfImage = true + return nil +} + +func (z *reader) finishDecode(alreadySeenEOL bool) error { + numberOfEOLs := 0 + switch z.subFormat { + case Group3: + if z.truncated { + return nil + } + // The stream ends with a RTC (Return To Control) of 6 consecutive + // EOL's, but we should have already just seen an EOL, either in + // z.startDecode (for a zero-height image) or in z.decodeRow. + numberOfEOLs = 5 + + case Group4: + autoDetectHeight := z.rowsRemaining < 0 + if autoDetectHeight { + // Aligning to a byte boundary was already handled by reader.Read. + } else if z.align { + z.br.alignToByteBoundary() + } + // The stream ends with two EOL's. If the first one is missing, and we + // had an explicit image height, we just assume that the trailing two + // EOL's were truncated and return a nil error. + if err := z.decodeEOL(); err != nil { + if (err == errMissingEOL) && !autoDetectHeight { + z.truncated = true + return nil + } + return err + } + numberOfEOLs = 1 + + default: + return errUnsupportedSubFormat + } + + if alreadySeenEOL { + numberOfEOLs-- + } + for ; numberOfEOLs > 0; numberOfEOLs-- { + if err := z.decodeEOL(); err != nil { + return err + } + } + return nil +} + +func (z *reader) decodeEOL() error { + return decodeEOL(&z.br) +} + +func (z *reader) decodeRow(finalRow bool) error { + z.wi = 0 + z.atStartOfRow = true + z.penColorIsWhite = true + + if z.align { + z.br.alignToByteBoundary() + } + + switch z.subFormat { + case Group3: + for ; z.wi < len(z.curr); z.atStartOfRow = false { + if err := z.decodeRun(); err != nil { + return err + } + } + err := z.decodeEOL() + if finalRow && (err == errMissingEOL) { + z.truncated = true + return nil + } + return err + + case Group4: + for ; z.wi < len(z.curr); z.atStartOfRow = false { + mode, err := decode(&z.br, modeDecodeTable[:]) + if err != nil { + return err + } + rm := readerMode{} + if mode < uint32(len(readerModes)) { + rm = readerModes[mode] + } + if rm.function == nil { + return errInvalidMode + } + if err := rm.function(z, rm.arg); err != nil { + return err + } + } + return nil + } + + return errUnsupportedSubFormat +} + +func (z *reader) decodeRun() error { + table := blackDecodeTable[:] + if z.penColorIsWhite { + table = whiteDecodeTable[:] + } + + total := 0 + for { + n, err := decode(&z.br, table) + if err != nil { + return err + } + if n > maxWidth { + panic("unreachable") + } + total += int(n) + if total > maxWidth { + return errRunLengthTooLong + } + // Anything 0x3F or below is a terminal code. + if n <= 0x3F { + break + } + } + + if total > (len(z.curr) - z.wi) { + return errRunLengthOverflowsWidth + } + dst := z.curr[z.wi : z.wi+total] + penColor := z.penColor() + for i := range dst { + dst[i] = penColor + } + z.wi += total + z.penColorIsWhite = !z.penColorIsWhite + + return nil +} + +// The various modes' semantics are based on determining a row of pixels' +// "changing elements": those pixels whose color differs from the one on its +// immediate left. +// +// The row above the first row is implicitly all white. Similarly, the column +// to the left of the first column is implicitly all white. +// +// For example, here's Figure 1 in "ITU-T Recommendation T.6", where the +// current and previous rows contain black (B) and white (w) pixels. The a? +// indexes point into curr, the b? indexes point into prev. +// +// b1 b2 +// v v +// prev: BBBBBwwwwwBBBwwwww +// curr: BBBwwwwwBBBBBBwwww +// ^ ^ ^ +// a0 a1 a2 +// +// a0 is the "reference element" or current decoder position, roughly +// equivalent to what this implementation calls reader.wi. +// +// a1 is the next changing element to the right of a0, on the "coding line" +// (the current row). +// +// a2 is the next changing element to the right of a1, again on curr. +// +// b1 is the first changing element on the "reference line" (the previous row) +// to the right of a0 and of opposite color to a0. +// +// b2 is the next changing element to the right of b1, again on prev. +// +// The various modes calculate a1 (and a2, for modeH): +// - modePass calculates that a1 is at or to the right of b2. +// - modeH calculates a1 and a2 without considering b1 or b2. +// - modeV* calculates a1 to be b1 plus an adjustment (between -3 and +3). + +const ( + findB1 = false + findB2 = true +) + +// findB finds either the b1 or b2 value. +func (z *reader) findB(whichB bool) int { + // The initial row is a special case. The previous row is implicitly all + // white, so that there are no changing pixel elements. We return b1 or b2 + // to be at the end of the row. + if len(z.prev) != len(z.curr) { + return len(z.curr) + } + + i := z.wi + + if z.atStartOfRow { + // a0 is implicitly at -1, on a white pixel. b1 is the first black + // pixel in the previous row. b2 is the first white pixel after that. + for ; (i < len(z.prev)) && (z.prev[i] == 0xFF); i++ { + } + if whichB == findB2 { + for ; (i < len(z.prev)) && (z.prev[i] == 0x00); i++ { + } + } + return i + } + + // As per figure 1 above, assume that the current pen color is white. + // First, walk past every contiguous black pixel in prev, starting at a0. + oppositeColor := ^z.penColor() + for ; (i < len(z.prev)) && (z.prev[i] == oppositeColor); i++ { + } + + // Then walk past every contiguous white pixel. + penColor := ^oppositeColor + for ; (i < len(z.prev)) && (z.prev[i] == penColor); i++ { + } + + // We're now at a black pixel (or at the end of the row). That's b1. + if whichB == findB2 { + // If we're looking for b2, walk past every contiguous black pixel + // again. + oppositeColor := ^penColor + for ; (i < len(z.prev)) && (z.prev[i] == oppositeColor); i++ { + } + } + + return i +} + +type readerMode struct { + function func(z *reader, arg int) error + arg int +} + +var readerModes = [...]readerMode{ + modePass: {function: readerModePass}, + modeH: {function: readerModeH}, + modeV0: {function: readerModeV, arg: +0}, + modeVR1: {function: readerModeV, arg: +1}, + modeVR2: {function: readerModeV, arg: +2}, + modeVR3: {function: readerModeV, arg: +3}, + modeVL1: {function: readerModeV, arg: -1}, + modeVL2: {function: readerModeV, arg: -2}, + modeVL3: {function: readerModeV, arg: -3}, + modeExt: {function: readerModeExt}, +} + +func readerModePass(z *reader, arg int) error { + b2 := z.findB(findB2) + if (b2 < z.wi) || (len(z.curr) < b2) { + return errInvalidOffset + } + dst := z.curr[z.wi:b2] + penColor := z.penColor() + for i := range dst { + dst[i] = penColor + } + z.wi = b2 + return nil +} + +func readerModeH(z *reader, arg int) error { + // The first iteration finds a1. The second finds a2. + for i := 0; i < 2; i++ { + if err := z.decodeRun(); err != nil { + return err + } + } + return nil +} + +func readerModeV(z *reader, arg int) error { + a1 := z.findB(findB1) + arg + if (a1 < z.wi) || (len(z.curr) < a1) { + return errInvalidOffset + } + dst := z.curr[z.wi:a1] + penColor := z.penColor() + for i := range dst { + dst[i] = penColor + } + z.wi = a1 + z.penColorIsWhite = !z.penColorIsWhite + return nil +} + +func readerModeExt(z *reader, arg int) error { + return errUnsupportedMode +} + +// DecodeIntoGray decodes the CCITT-formatted data in r into dst. +// +// It returns an error if dst's width and height don't match the implied width +// and height of CCITT-formatted data. +func DecodeIntoGray(dst *image.Gray, r io.Reader, order Order, sf SubFormat, opts *Options) error { + bounds := dst.Bounds() + if (bounds.Dx() < 0) || (bounds.Dy() < 0) { + return errInvalidBounds + } + if bounds.Dx() > maxWidth { + return errUnsupportedWidth + } + + z := reader{ + br: bitReader{r: r, order: order}, + subFormat: sf, + align: (opts != nil) && opts.Align, + invert: (opts != nil) && opts.Invert, + width: bounds.Dx(), + } + if err := z.startDecode(); err != nil { + return err + } + + width := bounds.Dx() + for y := bounds.Min.Y; y < bounds.Max.Y; y++ { + p := (y - bounds.Min.Y) * dst.Stride + z.curr = dst.Pix[p : p+width] + if err := z.decodeRow(y+1 == bounds.Max.Y); err != nil { + return err + } + z.curr, z.prev = nil, z.curr + } + + if err := z.finishDecode(false); err != nil { + return err + } + + if z.invert { + for y := bounds.Min.Y; y < bounds.Max.Y; y++ { + p := (y - bounds.Min.Y) * dst.Stride + invertBytes(dst.Pix[p : p+width]) + } + } + + return nil +} + +// NewReader returns an io.Reader that decodes the CCITT-formatted data in r. +// The resultant byte stream is one bit per pixel (MSB first), with 1 meaning +// white and 0 meaning black. Each row in the result is byte-aligned. +// +// A negative height, such as passing AutoDetectHeight, means that the image +// height is not known in advance. A negative width is invalid. +func NewReader(r io.Reader, order Order, sf SubFormat, width int, height int, opts *Options) io.Reader { + readErr := error(nil) + if width < 0 { + readErr = errInvalidBounds + } else if width > maxWidth { + readErr = errUnsupportedWidth + } + + return &reader{ + br: bitReader{r: r, order: order}, + subFormat: sf, + align: (opts != nil) && opts.Align, + invert: (opts != nil) && opts.Invert, + width: width, + rowsRemaining: height, + readErr: readErr, + } +} diff --git a/vendor/golang.org/x/image/ccitt/table.go b/vendor/golang.org/x/image/ccitt/table.go new file mode 100644 index 00000000..ef7ea9d4 --- /dev/null +++ b/vendor/golang.org/x/image/ccitt/table.go @@ -0,0 +1,972 @@ +// generated by "go run gen.go". DO NOT EDIT. + +package ccitt + +// Each decodeTable is represented by an array of [2]int16's: a binary tree. +// Each array element (other than element 0, which means invalid) is a branch +// node in that tree. The root node is always element 1 (the second element). +// +// To walk the tree, look at the next bit in the bit stream, using it to select +// the first or second element of the [2]int16. If that int16 is 0, we have an +// invalid code. If it is positive, go to that branch node. If it is negative, +// then we have a leaf node, whose value is the bitwise complement (the ^ +// operator) of that int16. +// +// Comments above each decodeTable also show the same structure visually. The +// "b123" lines show the 123'rd branch node. The "=XXXXX" lines show an invalid +// code. The "=v1234" lines show a leaf node with value 1234. When reading the +// bit stream, a 0 or 1 bit means to go up or down, as you move left to right. +// +// For example, in modeDecodeTable, branch node b005 is three steps up from the +// root node, meaning that we have already seen "000". If the next bit is "0" +// then we move to branch node b006. Otherwise, the next bit is "1", and we +// move to the leaf node v0000 (also known as the modePass constant). Indeed, +// the bits that encode modePass are "0001". +// +// Tables 1, 2 and 3 come from the "ITU-T Recommendation T.6: FACSIMILE CODING +// SCHEMES AND CODING CONTROL FUNCTIONS FOR GROUP 4 FACSIMILE APPARATUS" +// specification: +// +// https://www.itu.int/rec/dologin_pub.asp?lang=e&id=T-REC-T.6-198811-I!!PDF-E&type=items + +// modeDecodeTable represents Table 1 and the End-of-Line code. +// +// +=XXXXX +// b009 +-+ +// | +=v0009 +// b007 +-+ +// | | +=v0008 +// b010 | +-+ +// | +=v0005 +// b006 +-+ +// | | +=v0007 +// b008 | +-+ +// | +=v0004 +// b005 +-+ +// | +=v0000 +// b003 +-+ +// | +=v0001 +// b002 +-+ +// | | +=v0006 +// b004 | +-+ +// | +=v0003 +// b001 +-+ +// +=v0002 +var modeDecodeTable = [...][2]int16{ + 0: {0, 0}, + 1: {2, ^2}, + 2: {3, 4}, + 3: {5, ^1}, + 4: {^6, ^3}, + 5: {6, ^0}, + 6: {7, 8}, + 7: {9, 10}, + 8: {^7, ^4}, + 9: {0, ^9}, + 10: {^8, ^5}, +} + +// whiteDecodeTable represents Tables 2 and 3 for a white run. +// +// +=XXXXX +// b059 +-+ +// | | +=v1792 +// b096 | | +-+ +// | | | | +=v1984 +// b100 | | | +-+ +// | | | +=v2048 +// b094 | | +-+ +// | | | | +=v2112 +// b101 | | | | +-+ +// | | | | | +=v2176 +// b097 | | | +-+ +// | | | | +=v2240 +// b102 | | | +-+ +// | | | +=v2304 +// b085 | +-+ +// | | +=v1856 +// b098 | | +-+ +// | | | +=v1920 +// b095 | +-+ +// | | +=v2368 +// b103 | | +-+ +// | | | +=v2432 +// b099 | +-+ +// | | +=v2496 +// b104 | +-+ +// | +=v2560 +// b040 +-+ +// | | +=v0029 +// b060 | +-+ +// | +=v0030 +// b026 +-+ +// | | +=v0045 +// b061 | | +-+ +// | | | +=v0046 +// b041 | +-+ +// | +=v0022 +// b016 +-+ +// | | +=v0023 +// b042 | | +-+ +// | | | | +=v0047 +// b062 | | | +-+ +// | | | +=v0048 +// b027 | +-+ +// | +=v0013 +// b008 +-+ +// | | +=v0020 +// b043 | | +-+ +// | | | | +=v0033 +// b063 | | | +-+ +// | | | +=v0034 +// b028 | | +-+ +// | | | | +=v0035 +// b064 | | | | +-+ +// | | | | | +=v0036 +// b044 | | | +-+ +// | | | | +=v0037 +// b065 | | | +-+ +// | | | +=v0038 +// b017 | +-+ +// | | +=v0019 +// b045 | | +-+ +// | | | | +=v0031 +// b066 | | | +-+ +// | | | +=v0032 +// b029 | +-+ +// | +=v0001 +// b004 +-+ +// | | +=v0012 +// b030 | | +-+ +// | | | | +=v0053 +// b067 | | | | +-+ +// | | | | | +=v0054 +// b046 | | | +-+ +// | | | +=v0026 +// b018 | | +-+ +// | | | | +=v0039 +// b068 | | | | +-+ +// | | | | | +=v0040 +// b047 | | | | +-+ +// | | | | | | +=v0041 +// b069 | | | | | +-+ +// | | | | | +=v0042 +// b031 | | | +-+ +// | | | | +=v0043 +// b070 | | | | +-+ +// | | | | | +=v0044 +// b048 | | | +-+ +// | | | +=v0021 +// b009 | +-+ +// | | +=v0028 +// b049 | | +-+ +// | | | | +=v0061 +// b071 | | | +-+ +// | | | +=v0062 +// b032 | | +-+ +// | | | | +=v0063 +// b072 | | | | +-+ +// | | | | | +=v0000 +// b050 | | | +-+ +// | | | | +=v0320 +// b073 | | | +-+ +// | | | +=v0384 +// b019 | +-+ +// | +=v0010 +// b002 +-+ +// | | +=v0011 +// b020 | | +-+ +// | | | | +=v0027 +// b051 | | | | +-+ +// | | | | | | +=v0059 +// b074 | | | | | +-+ +// | | | | | +=v0060 +// b033 | | | +-+ +// | | | | +=v1472 +// b086 | | | | +-+ +// | | | | | +=v1536 +// b075 | | | | +-+ +// | | | | | | +=v1600 +// b087 | | | | | +-+ +// | | | | | +=v1728 +// b052 | | | +-+ +// | | | +=v0018 +// b010 | | +-+ +// | | | | +=v0024 +// b053 | | | | +-+ +// | | | | | | +=v0049 +// b076 | | | | | +-+ +// | | | | | +=v0050 +// b034 | | | | +-+ +// | | | | | | +=v0051 +// b077 | | | | | | +-+ +// | | | | | | | +=v0052 +// b054 | | | | | +-+ +// | | | | | +=v0025 +// b021 | | | +-+ +// | | | | +=v0055 +// b078 | | | | +-+ +// | | | | | +=v0056 +// b055 | | | | +-+ +// | | | | | | +=v0057 +// b079 | | | | | +-+ +// | | | | | +=v0058 +// b035 | | | +-+ +// | | | +=v0192 +// b005 | +-+ +// | | +=v1664 +// b036 | | +-+ +// | | | | +=v0448 +// b080 | | | | +-+ +// | | | | | +=v0512 +// b056 | | | +-+ +// | | | | +=v0704 +// b088 | | | | +-+ +// | | | | | +=v0768 +// b081 | | | +-+ +// | | | +=v0640 +// b022 | | +-+ +// | | | | +=v0576 +// b082 | | | | +-+ +// | | | | | | +=v0832 +// b089 | | | | | +-+ +// | | | | | +=v0896 +// b057 | | | | +-+ +// | | | | | | +=v0960 +// b090 | | | | | | +-+ +// | | | | | | | +=v1024 +// b083 | | | | | +-+ +// | | | | | | +=v1088 +// b091 | | | | | +-+ +// | | | | | +=v1152 +// b037 | | | +-+ +// | | | | +=v1216 +// b092 | | | | +-+ +// | | | | | +=v1280 +// b084 | | | | +-+ +// | | | | | | +=v1344 +// b093 | | | | | +-+ +// | | | | | +=v1408 +// b058 | | | +-+ +// | | | +=v0256 +// b011 | +-+ +// | +=v0002 +// b001 +-+ +// | +=v0003 +// b012 | +-+ +// | | | +=v0128 +// b023 | | +-+ +// | | +=v0008 +// b006 | +-+ +// | | | +=v0009 +// b024 | | | +-+ +// | | | | | +=v0016 +// b038 | | | | +-+ +// | | | | +=v0017 +// b013 | | +-+ +// | | +=v0004 +// b003 +-+ +// | +=v0005 +// b014 | +-+ +// | | | +=v0014 +// b039 | | | +-+ +// | | | | +=v0015 +// b025 | | +-+ +// | | +=v0064 +// b007 +-+ +// | +=v0006 +// b015 +-+ +// +=v0007 +var whiteDecodeTable = [...][2]int16{ + 0: {0, 0}, + 1: {2, 3}, + 2: {4, 5}, + 3: {6, 7}, + 4: {8, 9}, + 5: {10, 11}, + 6: {12, 13}, + 7: {14, 15}, + 8: {16, 17}, + 9: {18, 19}, + 10: {20, 21}, + 11: {22, ^2}, + 12: {^3, 23}, + 13: {24, ^4}, + 14: {^5, 25}, + 15: {^6, ^7}, + 16: {26, 27}, + 17: {28, 29}, + 18: {30, 31}, + 19: {32, ^10}, + 20: {^11, 33}, + 21: {34, 35}, + 22: {36, 37}, + 23: {^128, ^8}, + 24: {^9, 38}, + 25: {39, ^64}, + 26: {40, 41}, + 27: {42, ^13}, + 28: {43, 44}, + 29: {45, ^1}, + 30: {^12, 46}, + 31: {47, 48}, + 32: {49, 50}, + 33: {51, 52}, + 34: {53, 54}, + 35: {55, ^192}, + 36: {^1664, 56}, + 37: {57, 58}, + 38: {^16, ^17}, + 39: {^14, ^15}, + 40: {59, 60}, + 41: {61, ^22}, + 42: {^23, 62}, + 43: {^20, 63}, + 44: {64, 65}, + 45: {^19, 66}, + 46: {67, ^26}, + 47: {68, 69}, + 48: {70, ^21}, + 49: {^28, 71}, + 50: {72, 73}, + 51: {^27, 74}, + 52: {75, ^18}, + 53: {^24, 76}, + 54: {77, ^25}, + 55: {78, 79}, + 56: {80, 81}, + 57: {82, 83}, + 58: {84, ^256}, + 59: {0, 85}, + 60: {^29, ^30}, + 61: {^45, ^46}, + 62: {^47, ^48}, + 63: {^33, ^34}, + 64: {^35, ^36}, + 65: {^37, ^38}, + 66: {^31, ^32}, + 67: {^53, ^54}, + 68: {^39, ^40}, + 69: {^41, ^42}, + 70: {^43, ^44}, + 71: {^61, ^62}, + 72: {^63, ^0}, + 73: {^320, ^384}, + 74: {^59, ^60}, + 75: {86, 87}, + 76: {^49, ^50}, + 77: {^51, ^52}, + 78: {^55, ^56}, + 79: {^57, ^58}, + 80: {^448, ^512}, + 81: {88, ^640}, + 82: {^576, 89}, + 83: {90, 91}, + 84: {92, 93}, + 85: {94, 95}, + 86: {^1472, ^1536}, + 87: {^1600, ^1728}, + 88: {^704, ^768}, + 89: {^832, ^896}, + 90: {^960, ^1024}, + 91: {^1088, ^1152}, + 92: {^1216, ^1280}, + 93: {^1344, ^1408}, + 94: {96, 97}, + 95: {98, 99}, + 96: {^1792, 100}, + 97: {101, 102}, + 98: {^1856, ^1920}, + 99: {103, 104}, + 100: {^1984, ^2048}, + 101: {^2112, ^2176}, + 102: {^2240, ^2304}, + 103: {^2368, ^2432}, + 104: {^2496, ^2560}, +} + +// blackDecodeTable represents Tables 2 and 3 for a black run. +// +// +=XXXXX +// b017 +-+ +// | | +=v1792 +// b042 | | +-+ +// | | | | +=v1984 +// b063 | | | +-+ +// | | | +=v2048 +// b029 | | +-+ +// | | | | +=v2112 +// b064 | | | | +-+ +// | | | | | +=v2176 +// b043 | | | +-+ +// | | | | +=v2240 +// b065 | | | +-+ +// | | | +=v2304 +// b022 | +-+ +// | | +=v1856 +// b044 | | +-+ +// | | | +=v1920 +// b030 | +-+ +// | | +=v2368 +// b066 | | +-+ +// | | | +=v2432 +// b045 | +-+ +// | | +=v2496 +// b067 | +-+ +// | +=v2560 +// b013 +-+ +// | | +=v0018 +// b031 | | +-+ +// | | | | +=v0052 +// b068 | | | | +-+ +// | | | | | | +=v0640 +// b095 | | | | | +-+ +// | | | | | +=v0704 +// b046 | | | +-+ +// | | | | +=v0768 +// b096 | | | | +-+ +// | | | | | +=v0832 +// b069 | | | +-+ +// | | | +=v0055 +// b023 | | +-+ +// | | | | +=v0056 +// b070 | | | | +-+ +// | | | | | | +=v1280 +// b097 | | | | | +-+ +// | | | | | +=v1344 +// b047 | | | | +-+ +// | | | | | | +=v1408 +// b098 | | | | | | +-+ +// | | | | | | | +=v1472 +// b071 | | | | | +-+ +// | | | | | +=v0059 +// b032 | | | +-+ +// | | | | +=v0060 +// b072 | | | | +-+ +// | | | | | | +=v1536 +// b099 | | | | | +-+ +// | | | | | +=v1600 +// b048 | | | +-+ +// | | | +=v0024 +// b018 | +-+ +// | | +=v0025 +// b049 | | +-+ +// | | | | +=v1664 +// b100 | | | | +-+ +// | | | | | +=v1728 +// b073 | | | +-+ +// | | | +=v0320 +// b033 | | +-+ +// | | | | +=v0384 +// b074 | | | | +-+ +// | | | | | +=v0448 +// b050 | | | +-+ +// | | | | +=v0512 +// b101 | | | | +-+ +// | | | | | +=v0576 +// b075 | | | +-+ +// | | | +=v0053 +// b024 | +-+ +// | | +=v0054 +// b076 | | +-+ +// | | | | +=v0896 +// b102 | | | +-+ +// | | | +=v0960 +// b051 | | +-+ +// | | | | +=v1024 +// b103 | | | | +-+ +// | | | | | +=v1088 +// b077 | | | +-+ +// | | | | +=v1152 +// b104 | | | +-+ +// | | | +=v1216 +// b034 | +-+ +// | +=v0064 +// b010 +-+ +// | | +=v0013 +// b019 | | +-+ +// | | | | +=v0023 +// b052 | | | | +-+ +// | | | | | | +=v0050 +// b078 | | | | | +-+ +// | | | | | +=v0051 +// b035 | | | | +-+ +// | | | | | | +=v0044 +// b079 | | | | | | +-+ +// | | | | | | | +=v0045 +// b053 | | | | | +-+ +// | | | | | | +=v0046 +// b080 | | | | | +-+ +// | | | | | +=v0047 +// b025 | | | +-+ +// | | | | +=v0057 +// b081 | | | | +-+ +// | | | | | +=v0058 +// b054 | | | | +-+ +// | | | | | | +=v0061 +// b082 | | | | | +-+ +// | | | | | +=v0256 +// b036 | | | +-+ +// | | | +=v0016 +// b014 | +-+ +// | | +=v0017 +// b037 | | +-+ +// | | | | +=v0048 +// b083 | | | | +-+ +// | | | | | +=v0049 +// b055 | | | +-+ +// | | | | +=v0062 +// b084 | | | +-+ +// | | | +=v0063 +// b026 | | +-+ +// | | | | +=v0030 +// b085 | | | | +-+ +// | | | | | +=v0031 +// b056 | | | | +-+ +// | | | | | | +=v0032 +// b086 | | | | | +-+ +// | | | | | +=v0033 +// b038 | | | +-+ +// | | | | +=v0040 +// b087 | | | | +-+ +// | | | | | +=v0041 +// b057 | | | +-+ +// | | | +=v0022 +// b020 | +-+ +// | +=v0014 +// b008 +-+ +// | | +=v0010 +// b015 | | +-+ +// | | | +=v0011 +// b011 | +-+ +// | | +=v0015 +// b027 | | +-+ +// | | | | +=v0128 +// b088 | | | | +-+ +// | | | | | +=v0192 +// b058 | | | | +-+ +// | | | | | | +=v0026 +// b089 | | | | | +-+ +// | | | | | +=v0027 +// b039 | | | +-+ +// | | | | +=v0028 +// b090 | | | | +-+ +// | | | | | +=v0029 +// b059 | | | +-+ +// | | | +=v0019 +// b021 | | +-+ +// | | | | +=v0020 +// b060 | | | | +-+ +// | | | | | | +=v0034 +// b091 | | | | | +-+ +// | | | | | +=v0035 +// b040 | | | | +-+ +// | | | | | | +=v0036 +// b092 | | | | | | +-+ +// | | | | | | | +=v0037 +// b061 | | | | | +-+ +// | | | | | | +=v0038 +// b093 | | | | | +-+ +// | | | | | +=v0039 +// b028 | | | +-+ +// | | | | +=v0021 +// b062 | | | | +-+ +// | | | | | | +=v0042 +// b094 | | | | | +-+ +// | | | | | +=v0043 +// b041 | | | +-+ +// | | | +=v0000 +// b016 | +-+ +// | +=v0012 +// b006 +-+ +// | | +=v0009 +// b012 | | +-+ +// | | | +=v0008 +// b009 | +-+ +// | +=v0007 +// b004 +-+ +// | | +=v0006 +// b007 | +-+ +// | +=v0005 +// b002 +-+ +// | | +=v0001 +// b005 | +-+ +// | +=v0004 +// b001 +-+ +// | +=v0003 +// b003 +-+ +// +=v0002 +var blackDecodeTable = [...][2]int16{ + 0: {0, 0}, + 1: {2, 3}, + 2: {4, 5}, + 3: {^3, ^2}, + 4: {6, 7}, + 5: {^1, ^4}, + 6: {8, 9}, + 7: {^6, ^5}, + 8: {10, 11}, + 9: {12, ^7}, + 10: {13, 14}, + 11: {15, 16}, + 12: {^9, ^8}, + 13: {17, 18}, + 14: {19, 20}, + 15: {^10, ^11}, + 16: {21, ^12}, + 17: {0, 22}, + 18: {23, 24}, + 19: {^13, 25}, + 20: {26, ^14}, + 21: {27, 28}, + 22: {29, 30}, + 23: {31, 32}, + 24: {33, 34}, + 25: {35, 36}, + 26: {37, 38}, + 27: {^15, 39}, + 28: {40, 41}, + 29: {42, 43}, + 30: {44, 45}, + 31: {^18, 46}, + 32: {47, 48}, + 33: {49, 50}, + 34: {51, ^64}, + 35: {52, 53}, + 36: {54, ^16}, + 37: {^17, 55}, + 38: {56, 57}, + 39: {58, 59}, + 40: {60, 61}, + 41: {62, ^0}, + 42: {^1792, 63}, + 43: {64, 65}, + 44: {^1856, ^1920}, + 45: {66, 67}, + 46: {68, 69}, + 47: {70, 71}, + 48: {72, ^24}, + 49: {^25, 73}, + 50: {74, 75}, + 51: {76, 77}, + 52: {^23, 78}, + 53: {79, 80}, + 54: {81, 82}, + 55: {83, 84}, + 56: {85, 86}, + 57: {87, ^22}, + 58: {88, 89}, + 59: {90, ^19}, + 60: {^20, 91}, + 61: {92, 93}, + 62: {^21, 94}, + 63: {^1984, ^2048}, + 64: {^2112, ^2176}, + 65: {^2240, ^2304}, + 66: {^2368, ^2432}, + 67: {^2496, ^2560}, + 68: {^52, 95}, + 69: {96, ^55}, + 70: {^56, 97}, + 71: {98, ^59}, + 72: {^60, 99}, + 73: {100, ^320}, + 74: {^384, ^448}, + 75: {101, ^53}, + 76: {^54, 102}, + 77: {103, 104}, + 78: {^50, ^51}, + 79: {^44, ^45}, + 80: {^46, ^47}, + 81: {^57, ^58}, + 82: {^61, ^256}, + 83: {^48, ^49}, + 84: {^62, ^63}, + 85: {^30, ^31}, + 86: {^32, ^33}, + 87: {^40, ^41}, + 88: {^128, ^192}, + 89: {^26, ^27}, + 90: {^28, ^29}, + 91: {^34, ^35}, + 92: {^36, ^37}, + 93: {^38, ^39}, + 94: {^42, ^43}, + 95: {^640, ^704}, + 96: {^768, ^832}, + 97: {^1280, ^1344}, + 98: {^1408, ^1472}, + 99: {^1536, ^1600}, + 100: {^1664, ^1728}, + 101: {^512, ^576}, + 102: {^896, ^960}, + 103: {^1024, ^1088}, + 104: {^1152, ^1216}, +} + +const maxCodeLength = 13 + +// Each encodeTable is represented by an array of bitStrings. + +// bitString is a pair of uint32 values representing a bit code. +// The nBits low bits of bits make up the actual bit code. +// Eg. bitString{0x0004, 8} represents the bitcode "00000100". +type bitString struct { + bits uint32 + nBits uint32 +} + +// modeEncodeTable represents Table 1 and the End-of-Line code. +var modeEncodeTable = [...]bitString{ + 0: {0x0001, 4}, // "0001" + 1: {0x0001, 3}, // "001" + 2: {0x0001, 1}, // "1" + 3: {0x0003, 3}, // "011" + 4: {0x0003, 6}, // "000011" + 5: {0x0003, 7}, // "0000011" + 6: {0x0002, 3}, // "010" + 7: {0x0002, 6}, // "000010" + 8: {0x0002, 7}, // "0000010" + 9: {0x0001, 7}, // "0000001" +} + +// whiteEncodeTable2 represents Table 2 for a white run. +var whiteEncodeTable2 = [...]bitString{ + 0: {0x0035, 8}, // "00110101" + 1: {0x0007, 6}, // "000111" + 2: {0x0007, 4}, // "0111" + 3: {0x0008, 4}, // "1000" + 4: {0x000b, 4}, // "1011" + 5: {0x000c, 4}, // "1100" + 6: {0x000e, 4}, // "1110" + 7: {0x000f, 4}, // "1111" + 8: {0x0013, 5}, // "10011" + 9: {0x0014, 5}, // "10100" + 10: {0x0007, 5}, // "00111" + 11: {0x0008, 5}, // "01000" + 12: {0x0008, 6}, // "001000" + 13: {0x0003, 6}, // "000011" + 14: {0x0034, 6}, // "110100" + 15: {0x0035, 6}, // "110101" + 16: {0x002a, 6}, // "101010" + 17: {0x002b, 6}, // "101011" + 18: {0x0027, 7}, // "0100111" + 19: {0x000c, 7}, // "0001100" + 20: {0x0008, 7}, // "0001000" + 21: {0x0017, 7}, // "0010111" + 22: {0x0003, 7}, // "0000011" + 23: {0x0004, 7}, // "0000100" + 24: {0x0028, 7}, // "0101000" + 25: {0x002b, 7}, // "0101011" + 26: {0x0013, 7}, // "0010011" + 27: {0x0024, 7}, // "0100100" + 28: {0x0018, 7}, // "0011000" + 29: {0x0002, 8}, // "00000010" + 30: {0x0003, 8}, // "00000011" + 31: {0x001a, 8}, // "00011010" + 32: {0x001b, 8}, // "00011011" + 33: {0x0012, 8}, // "00010010" + 34: {0x0013, 8}, // "00010011" + 35: {0x0014, 8}, // "00010100" + 36: {0x0015, 8}, // "00010101" + 37: {0x0016, 8}, // "00010110" + 38: {0x0017, 8}, // "00010111" + 39: {0x0028, 8}, // "00101000" + 40: {0x0029, 8}, // "00101001" + 41: {0x002a, 8}, // "00101010" + 42: {0x002b, 8}, // "00101011" + 43: {0x002c, 8}, // "00101100" + 44: {0x002d, 8}, // "00101101" + 45: {0x0004, 8}, // "00000100" + 46: {0x0005, 8}, // "00000101" + 47: {0x000a, 8}, // "00001010" + 48: {0x000b, 8}, // "00001011" + 49: {0x0052, 8}, // "01010010" + 50: {0x0053, 8}, // "01010011" + 51: {0x0054, 8}, // "01010100" + 52: {0x0055, 8}, // "01010101" + 53: {0x0024, 8}, // "00100100" + 54: {0x0025, 8}, // "00100101" + 55: {0x0058, 8}, // "01011000" + 56: {0x0059, 8}, // "01011001" + 57: {0x005a, 8}, // "01011010" + 58: {0x005b, 8}, // "01011011" + 59: {0x004a, 8}, // "01001010" + 60: {0x004b, 8}, // "01001011" + 61: {0x0032, 8}, // "00110010" + 62: {0x0033, 8}, // "00110011" + 63: {0x0034, 8}, // "00110100" +} + +// whiteEncodeTable3 represents Table 3 for a white run. +var whiteEncodeTable3 = [...]bitString{ + 0: {0x001b, 5}, // "11011" + 1: {0x0012, 5}, // "10010" + 2: {0x0017, 6}, // "010111" + 3: {0x0037, 7}, // "0110111" + 4: {0x0036, 8}, // "00110110" + 5: {0x0037, 8}, // "00110111" + 6: {0x0064, 8}, // "01100100" + 7: {0x0065, 8}, // "01100101" + 8: {0x0068, 8}, // "01101000" + 9: {0x0067, 8}, // "01100111" + 10: {0x00cc, 9}, // "011001100" + 11: {0x00cd, 9}, // "011001101" + 12: {0x00d2, 9}, // "011010010" + 13: {0x00d3, 9}, // "011010011" + 14: {0x00d4, 9}, // "011010100" + 15: {0x00d5, 9}, // "011010101" + 16: {0x00d6, 9}, // "011010110" + 17: {0x00d7, 9}, // "011010111" + 18: {0x00d8, 9}, // "011011000" + 19: {0x00d9, 9}, // "011011001" + 20: {0x00da, 9}, // "011011010" + 21: {0x00db, 9}, // "011011011" + 22: {0x0098, 9}, // "010011000" + 23: {0x0099, 9}, // "010011001" + 24: {0x009a, 9}, // "010011010" + 25: {0x0018, 6}, // "011000" + 26: {0x009b, 9}, // "010011011" + 27: {0x0008, 11}, // "00000001000" + 28: {0x000c, 11}, // "00000001100" + 29: {0x000d, 11}, // "00000001101" + 30: {0x0012, 12}, // "000000010010" + 31: {0x0013, 12}, // "000000010011" + 32: {0x0014, 12}, // "000000010100" + 33: {0x0015, 12}, // "000000010101" + 34: {0x0016, 12}, // "000000010110" + 35: {0x0017, 12}, // "000000010111" + 36: {0x001c, 12}, // "000000011100" + 37: {0x001d, 12}, // "000000011101" + 38: {0x001e, 12}, // "000000011110" + 39: {0x001f, 12}, // "000000011111" +} + +// blackEncodeTable2 represents Table 2 for a black run. +var blackEncodeTable2 = [...]bitString{ + 0: {0x0037, 10}, // "0000110111" + 1: {0x0002, 3}, // "010" + 2: {0x0003, 2}, // "11" + 3: {0x0002, 2}, // "10" + 4: {0x0003, 3}, // "011" + 5: {0x0003, 4}, // "0011" + 6: {0x0002, 4}, // "0010" + 7: {0x0003, 5}, // "00011" + 8: {0x0005, 6}, // "000101" + 9: {0x0004, 6}, // "000100" + 10: {0x0004, 7}, // "0000100" + 11: {0x0005, 7}, // "0000101" + 12: {0x0007, 7}, // "0000111" + 13: {0x0004, 8}, // "00000100" + 14: {0x0007, 8}, // "00000111" + 15: {0x0018, 9}, // "000011000" + 16: {0x0017, 10}, // "0000010111" + 17: {0x0018, 10}, // "0000011000" + 18: {0x0008, 10}, // "0000001000" + 19: {0x0067, 11}, // "00001100111" + 20: {0x0068, 11}, // "00001101000" + 21: {0x006c, 11}, // "00001101100" + 22: {0x0037, 11}, // "00000110111" + 23: {0x0028, 11}, // "00000101000" + 24: {0x0017, 11}, // "00000010111" + 25: {0x0018, 11}, // "00000011000" + 26: {0x00ca, 12}, // "000011001010" + 27: {0x00cb, 12}, // "000011001011" + 28: {0x00cc, 12}, // "000011001100" + 29: {0x00cd, 12}, // "000011001101" + 30: {0x0068, 12}, // "000001101000" + 31: {0x0069, 12}, // "000001101001" + 32: {0x006a, 12}, // "000001101010" + 33: {0x006b, 12}, // "000001101011" + 34: {0x00d2, 12}, // "000011010010" + 35: {0x00d3, 12}, // "000011010011" + 36: {0x00d4, 12}, // "000011010100" + 37: {0x00d5, 12}, // "000011010101" + 38: {0x00d6, 12}, // "000011010110" + 39: {0x00d7, 12}, // "000011010111" + 40: {0x006c, 12}, // "000001101100" + 41: {0x006d, 12}, // "000001101101" + 42: {0x00da, 12}, // "000011011010" + 43: {0x00db, 12}, // "000011011011" + 44: {0x0054, 12}, // "000001010100" + 45: {0x0055, 12}, // "000001010101" + 46: {0x0056, 12}, // "000001010110" + 47: {0x0057, 12}, // "000001010111" + 48: {0x0064, 12}, // "000001100100" + 49: {0x0065, 12}, // "000001100101" + 50: {0x0052, 12}, // "000001010010" + 51: {0x0053, 12}, // "000001010011" + 52: {0x0024, 12}, // "000000100100" + 53: {0x0037, 12}, // "000000110111" + 54: {0x0038, 12}, // "000000111000" + 55: {0x0027, 12}, // "000000100111" + 56: {0x0028, 12}, // "000000101000" + 57: {0x0058, 12}, // "000001011000" + 58: {0x0059, 12}, // "000001011001" + 59: {0x002b, 12}, // "000000101011" + 60: {0x002c, 12}, // "000000101100" + 61: {0x005a, 12}, // "000001011010" + 62: {0x0066, 12}, // "000001100110" + 63: {0x0067, 12}, // "000001100111" +} + +// blackEncodeTable3 represents Table 3 for a black run. +var blackEncodeTable3 = [...]bitString{ + 0: {0x000f, 10}, // "0000001111" + 1: {0x00c8, 12}, // "000011001000" + 2: {0x00c9, 12}, // "000011001001" + 3: {0x005b, 12}, // "000001011011" + 4: {0x0033, 12}, // "000000110011" + 5: {0x0034, 12}, // "000000110100" + 6: {0x0035, 12}, // "000000110101" + 7: {0x006c, 13}, // "0000001101100" + 8: {0x006d, 13}, // "0000001101101" + 9: {0x004a, 13}, // "0000001001010" + 10: {0x004b, 13}, // "0000001001011" + 11: {0x004c, 13}, // "0000001001100" + 12: {0x004d, 13}, // "0000001001101" + 13: {0x0072, 13}, // "0000001110010" + 14: {0x0073, 13}, // "0000001110011" + 15: {0x0074, 13}, // "0000001110100" + 16: {0x0075, 13}, // "0000001110101" + 17: {0x0076, 13}, // "0000001110110" + 18: {0x0077, 13}, // "0000001110111" + 19: {0x0052, 13}, // "0000001010010" + 20: {0x0053, 13}, // "0000001010011" + 21: {0x0054, 13}, // "0000001010100" + 22: {0x0055, 13}, // "0000001010101" + 23: {0x005a, 13}, // "0000001011010" + 24: {0x005b, 13}, // "0000001011011" + 25: {0x0064, 13}, // "0000001100100" + 26: {0x0065, 13}, // "0000001100101" + 27: {0x0008, 11}, // "00000001000" + 28: {0x000c, 11}, // "00000001100" + 29: {0x000d, 11}, // "00000001101" + 30: {0x0012, 12}, // "000000010010" + 31: {0x0013, 12}, // "000000010011" + 32: {0x0014, 12}, // "000000010100" + 33: {0x0015, 12}, // "000000010101" + 34: {0x0016, 12}, // "000000010110" + 35: {0x0017, 12}, // "000000010111" + 36: {0x001c, 12}, // "000000011100" + 37: {0x001d, 12}, // "000000011101" + 38: {0x001e, 12}, // "000000011110" + 39: {0x001f, 12}, // "000000011111" +} + +// COPY PASTE table.go BEGIN + +const ( + modePass = iota // Pass + modeH // Horizontal + modeV0 // Vertical-0 + modeVR1 // Vertical-Right-1 + modeVR2 // Vertical-Right-2 + modeVR3 // Vertical-Right-3 + modeVL1 // Vertical-Left-1 + modeVL2 // Vertical-Left-2 + modeVL3 // Vertical-Left-3 + modeExt // Extension +) + +// COPY PASTE table.go END diff --git a/vendor/golang.org/x/image/ccitt/writer.go b/vendor/golang.org/x/image/ccitt/writer.go new file mode 100644 index 00000000..87130ab0 --- /dev/null +++ b/vendor/golang.org/x/image/ccitt/writer.go @@ -0,0 +1,102 @@ +// Copyright 2019 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 ccitt + +import ( + "encoding/binary" + "io" +) + +type bitWriter struct { + w io.Writer + + // order is whether to process w's bytes LSB first or MSB first. + order Order + + // The high nBits bits of the bits field hold encoded bits to be written to w. + bits uint64 + nBits uint32 + + // bytes[:bw] holds encoded bytes not yet written to w. + // Overflow protection is ensured by using a multiple of 8 as bytes length. + bw uint32 + bytes [1024]uint8 +} + +// flushBits copies 64 bits from b.bits to b.bytes. If b.bytes is then full, it +// is written to b.w. +func (b *bitWriter) flushBits() error { + binary.BigEndian.PutUint64(b.bytes[b.bw:], b.bits) + b.bits = 0 + b.nBits = 0 + b.bw += 8 + if b.bw < uint32(len(b.bytes)) { + return nil + } + b.bw = 0 + if b.order != MSB { + reverseBitsWithinBytes(b.bytes[:]) + } + _, err := b.w.Write(b.bytes[:]) + return err +} + +// close finalizes a bitcode stream by writing any +// pending bits to bitWriter's underlying io.Writer. +func (b *bitWriter) close() error { + // Write any encoded bits to bytes. + if b.nBits > 0 { + binary.BigEndian.PutUint64(b.bytes[b.bw:], b.bits) + b.bw += (b.nBits + 7) >> 3 + } + + if b.order != MSB { + reverseBitsWithinBytes(b.bytes[:b.bw]) + } + + // Write b.bw bytes to b.w. + _, err := b.w.Write(b.bytes[:b.bw]) + return err +} + +// alignToByteBoundary rounds b.nBits up to a multiple of 8. +// If all 64 bits are used, flush them to bitWriter's bytes. +func (b *bitWriter) alignToByteBoundary() error { + if b.nBits = (b.nBits + 7) &^ 7; b.nBits == 64 { + return b.flushBits() + } + return nil +} + +// writeCode writes a variable length bitcode to b's underlying io.Writer. +func (b *bitWriter) writeCode(bs bitString) error { + bits := bs.bits + nBits := bs.nBits + if 64-b.nBits >= nBits { + // b.bits has sufficient room for storing nBits bits. + b.bits |= uint64(bits) << (64 - nBits - b.nBits) + b.nBits += nBits + if b.nBits == 64 { + return b.flushBits() + } + return nil + } + + // Number of leading bits that fill b.bits. + i := 64 - b.nBits + + // Fill b.bits then flush and write remaining bits. + b.bits |= uint64(bits) >> (nBits - i) + b.nBits = 64 + + if err := b.flushBits(); err != nil { + return err + } + + nBits -= i + b.bits = uint64(bits) << (64 - nBits) + b.nBits = nBits + return nil +} diff --git a/vendor/golang.org/x/image/tiff/buffer.go b/vendor/golang.org/x/image/tiff/buffer.go new file mode 100644 index 00000000..d1801be4 --- /dev/null +++ b/vendor/golang.org/x/image/tiff/buffer.go @@ -0,0 +1,69 @@ +// 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 tiff + +import "io" + +// buffer buffers an io.Reader to satisfy io.ReaderAt. +type buffer struct { + r io.Reader + buf []byte +} + +// fill reads data from b.r until the buffer contains at least end bytes. +func (b *buffer) fill(end int) error { + m := len(b.buf) + if end > m { + if end > cap(b.buf) { + newcap := 1024 + for newcap < end { + newcap *= 2 + } + newbuf := make([]byte, end, newcap) + copy(newbuf, b.buf) + b.buf = newbuf + } else { + b.buf = b.buf[:end] + } + if n, err := io.ReadFull(b.r, b.buf[m:end]); err != nil { + end = m + n + b.buf = b.buf[:end] + return err + } + } + return nil +} + +func (b *buffer) ReadAt(p []byte, off int64) (int, error) { + o := int(off) + end := o + len(p) + if int64(end) != off+int64(len(p)) { + return 0, io.ErrUnexpectedEOF + } + + err := b.fill(end) + return copy(p, b.buf[o:end]), err +} + +// Slice returns a slice of the underlying buffer. The slice contains +// n bytes starting at offset off. +func (b *buffer) Slice(off, n int) ([]byte, error) { + end := off + n + if err := b.fill(end); err != nil { + return nil, err + } + return b.buf[off:end], nil +} + +// newReaderAt converts an io.Reader into an io.ReaderAt. +func newReaderAt(r io.Reader) io.ReaderAt { + if ra, ok := r.(io.ReaderAt); ok { + return ra + } + return &buffer{ + r: r, + buf: make([]byte, 0, 1024), + } +} diff --git a/vendor/golang.org/x/image/tiff/compress.go b/vendor/golang.org/x/image/tiff/compress.go new file mode 100644 index 00000000..3f176f00 --- /dev/null +++ b/vendor/golang.org/x/image/tiff/compress.go @@ -0,0 +1,58 @@ +// 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 tiff + +import ( + "bufio" + "io" +) + +type byteReader interface { + io.Reader + io.ByteReader +} + +// unpackBits decodes the PackBits-compressed data in src and returns the +// uncompressed data. +// +// The PackBits compression format is described in section 9 (p. 42) +// of the TIFF spec. +func unpackBits(r io.Reader) ([]byte, error) { + buf := make([]byte, 128) + dst := make([]byte, 0, 1024) + br, ok := r.(byteReader) + if !ok { + br = bufio.NewReader(r) + } + + for { + b, err := br.ReadByte() + if err != nil { + if err == io.EOF { + return dst, nil + } + return nil, err + } + code := int(int8(b)) + switch { + case code >= 0: + n, err := io.ReadFull(br, buf[:code+1]) + if err != nil { + return nil, err + } + dst = append(dst, buf[:n]...) + case code == -128: + // No-op. + default: + if b, err = br.ReadByte(); err != nil { + return nil, err + } + for j := 0; j < 1-code; j++ { + buf[j] = b + } + dst = append(dst, buf[:1-code]...) + } + } +} diff --git a/vendor/golang.org/x/image/tiff/consts.go b/vendor/golang.org/x/image/tiff/consts.go new file mode 100644 index 00000000..3e5f7f14 --- /dev/null +++ b/vendor/golang.org/x/image/tiff/consts.go @@ -0,0 +1,149 @@ +// 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 tiff + +// A tiff image file contains one or more images. The metadata +// of each image is contained in an Image File Directory (IFD), +// which contains entries of 12 bytes each and is described +// on page 14-16 of the specification. An IFD entry consists of +// +// - a tag, which describes the signification of the entry, +// - the data type and length of the entry, +// - the data itself or a pointer to it if it is more than 4 bytes. +// +// The presence of a length means that each IFD is effectively an array. + +const ( + leHeader = "II\x2A\x00" // Header for little-endian files. + beHeader = "MM\x00\x2A" // Header for big-endian files. + + ifdLen = 12 // Length of an IFD entry in bytes. +) + +// Data types (p. 14-16 of the spec). +const ( + dtByte = 1 + dtASCII = 2 + dtShort = 3 + dtLong = 4 + dtRational = 5 +) + +// The length of one instance of each data type in bytes. +var lengths = [...]uint32{0, 1, 1, 2, 4, 8} + +// Tags (see p. 28-41 of the spec). +const ( + tImageWidth = 256 + tImageLength = 257 + tBitsPerSample = 258 + tCompression = 259 + tPhotometricInterpretation = 262 + + tFillOrder = 266 + + tStripOffsets = 273 + tSamplesPerPixel = 277 + tRowsPerStrip = 278 + tStripByteCounts = 279 + + tT4Options = 292 // CCITT Group 3 options, a set of 32 flag bits. + tT6Options = 293 // CCITT Group 4 options, a set of 32 flag bits. + + tTileWidth = 322 + tTileLength = 323 + tTileOffsets = 324 + tTileByteCounts = 325 + + tXResolution = 282 + tYResolution = 283 + tResolutionUnit = 296 + + tPredictor = 317 + tColorMap = 320 + tExtraSamples = 338 + tSampleFormat = 339 +) + +// Compression types (defined in various places in the spec and supplements). +const ( + cNone = 1 + cCCITT = 2 + cG3 = 3 // Group 3 Fax. + cG4 = 4 // Group 4 Fax. + cLZW = 5 + cJPEGOld = 6 // Superseded by cJPEG. + cJPEG = 7 + cDeflate = 8 // zlib compression. + cPackBits = 32773 + cDeflateOld = 32946 // Superseded by cDeflate. +) + +// Photometric interpretation values (see p. 37 of the spec). +const ( + pWhiteIsZero = 0 + pBlackIsZero = 1 + pRGB = 2 + pPaletted = 3 + pTransMask = 4 // transparency mask + pCMYK = 5 + pYCbCr = 6 + pCIELab = 8 +) + +// Values for the tPredictor tag (page 64-65 of the spec). +const ( + prNone = 1 + prHorizontal = 2 +) + +// Values for the tResolutionUnit tag (page 18). +const ( + resNone = 1 + resPerInch = 2 // Dots per inch. + resPerCM = 3 // Dots per centimeter. +) + +// imageMode represents the mode of the image. +type imageMode int + +const ( + mBilevel imageMode = iota + mPaletted + mGray + mGrayInvert + mRGB + mRGBA + mNRGBA + mCMYK +) + +// CompressionType describes the type of compression used in Options. +type CompressionType int + +// Constants for supported compression types. +const ( + Uncompressed CompressionType = iota + Deflate + LZW + CCITTGroup3 + CCITTGroup4 +) + +// specValue returns the compression type constant from the TIFF spec that +// is equivalent to c. +func (c CompressionType) specValue() uint32 { + switch c { + case LZW: + return cLZW + case Deflate: + return cDeflate + case CCITTGroup3: + return cG3 + case CCITTGroup4: + return cG4 + } + return cNone +} diff --git a/vendor/golang.org/x/image/tiff/fuzz.go b/vendor/golang.org/x/image/tiff/fuzz.go new file mode 100644 index 00000000..ec52c788 --- /dev/null +++ b/vendor/golang.org/x/image/tiff/fuzz.go @@ -0,0 +1,29 @@ +// Copyright 2019 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. + +// +build gofuzz + +package tiff + +import "bytes" + +func Fuzz(data []byte) int { + cfg, err := DecodeConfig(bytes.NewReader(data)) + if err != nil { + return 0 + } + if cfg.Width*cfg.Height > 1e6 { + return 0 + } + img, err := Decode(bytes.NewReader(data)) + if err != nil { + return 0 + } + var w bytes.Buffer + err = Encode(&w, img, nil) + if err != nil { + panic(err) + } + return 1 +} diff --git a/vendor/golang.org/x/image/tiff/lzw/reader.go b/vendor/golang.org/x/image/tiff/lzw/reader.go new file mode 100644 index 00000000..78204ba9 --- /dev/null +++ b/vendor/golang.org/x/image/tiff/lzw/reader.go @@ -0,0 +1,272 @@ +// 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 lzw implements the Lempel-Ziv-Welch compressed data format, +// described in T. A. Welch, ``A Technique for High-Performance Data +// Compression'', Computer, 17(6) (June 1984), pp 8-19. +// +// In particular, it implements LZW as used by the TIFF file format, including +// an "off by one" algorithmic difference when compared to standard LZW. +package lzw // import "golang.org/x/image/tiff/lzw" + +/* +This file was branched from src/pkg/compress/lzw/reader.go in the +standard library. Differences from the original are marked with "NOTE". + +The tif_lzw.c file in the libtiff C library has this comment: + +---- +The 5.0 spec describes a different algorithm than Aldus +implements. Specifically, Aldus does code length transitions +one code earlier than should be done (for real LZW). +Earlier versions of this library implemented the correct +LZW algorithm, but emitted codes in a bit order opposite +to the TIFF spec. Thus, to maintain compatibility w/ Aldus +we interpret MSB-LSB ordered codes to be images written w/ +old versions of this library, but otherwise adhere to the +Aldus "off by one" algorithm. +---- + +The Go code doesn't read (invalid) TIFF files written by old versions of +libtiff, but the LZW algorithm in this package still differs from the one in +Go's standard package library to accomodate this "off by one" in valid TIFFs. +*/ + +import ( + "bufio" + "errors" + "fmt" + "io" +) + +// Order specifies the bit ordering in an LZW data stream. +type Order int + +const ( + // LSB means Least Significant Bits first, as used in the GIF file format. + LSB Order = iota + // MSB means Most Significant Bits first, as used in the TIFF and PDF + // file formats. + MSB +) + +const ( + maxWidth = 12 + decoderInvalidCode = 0xffff + flushBuffer = 1 << maxWidth +) + +// decoder is the state from which the readXxx method converts a byte +// stream into a code stream. +type decoder struct { + r io.ByteReader + bits uint32 + nBits uint + width uint + read func(*decoder) (uint16, error) // readLSB or readMSB + litWidth int // width in bits of literal codes + err error + + // The first 1<= 1<>= d.width + d.nBits -= d.width + return code, nil +} + +// readMSB returns the next code for "Most Significant Bits first" data. +func (d *decoder) readMSB() (uint16, error) { + for d.nBits < d.width { + x, err := d.r.ReadByte() + if err != nil { + return 0, err + } + d.bits |= uint32(x) << (24 - d.nBits) + d.nBits += 8 + } + code := uint16(d.bits >> (32 - d.width)) + d.bits <<= d.width + d.nBits -= d.width + return code, nil +} + +func (d *decoder) Read(b []byte) (int, error) { + for { + if len(d.toRead) > 0 { + n := copy(b, d.toRead) + d.toRead = d.toRead[n:] + return n, nil + } + if d.err != nil { + return 0, d.err + } + d.decode() + } +} + +// decode decompresses bytes from r and leaves them in d.toRead. +// read specifies how to decode bytes into codes. +// litWidth is the width in bits of literal codes. +func (d *decoder) decode() { + // Loop over the code stream, converting codes into decompressed bytes. +loop: + for { + code, err := d.read(d) + if err != nil { + if err == io.EOF { + err = io.ErrUnexpectedEOF + } + d.err = err + break + } + switch { + case code < d.clear: + // We have a literal code. + d.output[d.o] = uint8(code) + d.o++ + if d.last != decoderInvalidCode { + // Save what the hi code expands to. + d.suffix[d.hi] = uint8(code) + d.prefix[d.hi] = d.last + } + case code == d.clear: + d.width = 1 + uint(d.litWidth) + d.hi = d.eof + d.overflow = 1 << d.width + d.last = decoderInvalidCode + continue + case code == d.eof: + d.err = io.EOF + break loop + case code <= d.hi: + c, i := code, len(d.output)-1 + if code == d.hi && d.last != decoderInvalidCode { + // code == hi is a special case which expands to the last expansion + // followed by the head of the last expansion. To find the head, we walk + // the prefix chain until we find a literal code. + c = d.last + for c >= d.clear { + c = d.prefix[c] + } + d.output[i] = uint8(c) + i-- + c = d.last + } + // Copy the suffix chain into output and then write that to w. + for c >= d.clear { + d.output[i] = d.suffix[c] + i-- + c = d.prefix[c] + } + d.output[i] = uint8(c) + d.o += copy(d.output[d.o:], d.output[i:]) + if d.last != decoderInvalidCode { + // Save what the hi code expands to. + d.suffix[d.hi] = uint8(c) + d.prefix[d.hi] = d.last + } + default: + d.err = errors.New("lzw: invalid code") + break loop + } + d.last, d.hi = code, d.hi+1 + if d.hi+1 >= d.overflow { // NOTE: the "+1" is where TIFF's LZW differs from the standard algorithm. + if d.width == maxWidth { + d.last = decoderInvalidCode + } else { + d.width++ + d.overflow <<= 1 + } + } + if d.o >= flushBuffer { + break + } + } + // Flush pending output. + d.toRead = d.output[:d.o] + d.o = 0 +} + +var errClosed = errors.New("lzw: reader/writer is closed") + +func (d *decoder) Close() error { + d.err = errClosed // in case any Reads come along + return nil +} + +// NewReader creates a new io.ReadCloser. +// Reads from the returned io.ReadCloser read and decompress data from r. +// If r does not also implement io.ByteReader, +// the decompressor may read more data than necessary from r. +// It is the caller's responsibility to call Close on the ReadCloser when +// finished reading. +// The number of bits to use for literal codes, litWidth, must be in the +// range [2,8] and is typically 8. It must equal the litWidth +// used during compression. +func NewReader(r io.Reader, order Order, litWidth int) io.ReadCloser { + d := new(decoder) + switch order { + case LSB: + d.read = (*decoder).readLSB + case MSB: + d.read = (*decoder).readMSB + default: + d.err = errors.New("lzw: unknown order") + return d + } + if litWidth < 2 || 8 < litWidth { + d.err = fmt.Errorf("lzw: litWidth %d out of range", litWidth) + return d + } + if br, ok := r.(io.ByteReader); ok { + d.r = br + } else { + d.r = bufio.NewReader(r) + } + d.litWidth = litWidth + d.width = 1 + uint(litWidth) + d.clear = uint16(1) << uint(litWidth) + d.eof, d.hi = d.clear+1, d.clear+1 + d.overflow = uint16(1) << d.width + d.last = decoderInvalidCode + + return d +} diff --git a/vendor/golang.org/x/image/tiff/reader.go b/vendor/golang.org/x/image/tiff/reader.go new file mode 100644 index 00000000..de73f4b9 --- /dev/null +++ b/vendor/golang.org/x/image/tiff/reader.go @@ -0,0 +1,709 @@ +// 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 tiff implements a TIFF image decoder and encoder. +// +// The TIFF specification is at http://partners.adobe.com/public/developer/en/tiff/TIFF6.pdf +package tiff // import "golang.org/x/image/tiff" + +import ( + "compress/zlib" + "encoding/binary" + "fmt" + "image" + "image/color" + "io" + "io/ioutil" + "math" + + "golang.org/x/image/ccitt" + "golang.org/x/image/tiff/lzw" +) + +// A FormatError reports that the input is not a valid TIFF image. +type FormatError string + +func (e FormatError) Error() string { + return "tiff: invalid format: " + string(e) +} + +// An UnsupportedError reports that the input uses a valid but +// unimplemented feature. +type UnsupportedError string + +func (e UnsupportedError) Error() string { + return "tiff: unsupported feature: " + string(e) +} + +var errNoPixels = FormatError("not enough pixel data") + +type decoder struct { + r io.ReaderAt + byteOrder binary.ByteOrder + config image.Config + mode imageMode + bpp uint + features map[int][]uint + palette []color.Color + + buf []byte + off int // Current offset in buf. + v uint32 // Buffer value for reading with arbitrary bit depths. + nbits uint // Remaining number of bits in v. +} + +// firstVal returns the first uint of the features entry with the given tag, +// or 0 if the tag does not exist. +func (d *decoder) firstVal(tag int) uint { + f := d.features[tag] + if len(f) == 0 { + return 0 + } + return f[0] +} + +// ifdUint decodes the IFD entry in p, which must be of the Byte, Short +// or Long type, and returns the decoded uint values. +func (d *decoder) ifdUint(p []byte) (u []uint, err error) { + var raw []byte + if len(p) < ifdLen { + return nil, FormatError("bad IFD entry") + } + + datatype := d.byteOrder.Uint16(p[2:4]) + if dt := int(datatype); dt <= 0 || dt >= len(lengths) { + return nil, UnsupportedError("IFD entry datatype") + } + + count := d.byteOrder.Uint32(p[4:8]) + if count > math.MaxInt32/lengths[datatype] { + return nil, FormatError("IFD data too large") + } + if datalen := lengths[datatype] * count; datalen > 4 { + // The IFD contains a pointer to the real value. + raw = make([]byte, datalen) + _, err = d.r.ReadAt(raw, int64(d.byteOrder.Uint32(p[8:12]))) + } else { + raw = p[8 : 8+datalen] + } + if err != nil { + return nil, err + } + + u = make([]uint, count) + switch datatype { + case dtByte: + for i := uint32(0); i < count; i++ { + u[i] = uint(raw[i]) + } + case dtShort: + for i := uint32(0); i < count; i++ { + u[i] = uint(d.byteOrder.Uint16(raw[2*i : 2*(i+1)])) + } + case dtLong: + for i := uint32(0); i < count; i++ { + u[i] = uint(d.byteOrder.Uint32(raw[4*i : 4*(i+1)])) + } + default: + return nil, UnsupportedError("data type") + } + return u, nil +} + +// parseIFD decides whether the IFD entry in p is "interesting" and +// stows away the data in the decoder. It returns the tag number of the +// entry and an error, if any. +func (d *decoder) parseIFD(p []byte) (int, error) { + tag := d.byteOrder.Uint16(p[0:2]) + switch tag { + case tBitsPerSample, + tExtraSamples, + tPhotometricInterpretation, + tCompression, + tPredictor, + tStripOffsets, + tStripByteCounts, + tRowsPerStrip, + tTileWidth, + tTileLength, + tTileOffsets, + tTileByteCounts, + tImageLength, + tImageWidth, + tFillOrder, + tT4Options, + tT6Options: + val, err := d.ifdUint(p) + if err != nil { + return 0, err + } + d.features[int(tag)] = val + case tColorMap: + val, err := d.ifdUint(p) + if err != nil { + return 0, err + } + numcolors := len(val) / 3 + if len(val)%3 != 0 || numcolors <= 0 || numcolors > 256 { + return 0, FormatError("bad ColorMap length") + } + d.palette = make([]color.Color, numcolors) + for i := 0; i < numcolors; i++ { + d.palette[i] = color.RGBA64{ + uint16(val[i]), + uint16(val[i+numcolors]), + uint16(val[i+2*numcolors]), + 0xffff, + } + } + case tSampleFormat: + // Page 27 of the spec: If the SampleFormat is present and + // the value is not 1 [= unsigned integer data], a Baseline + // TIFF reader that cannot handle the SampleFormat value + // must terminate the import process gracefully. + val, err := d.ifdUint(p) + if err != nil { + return 0, err + } + for _, v := range val { + if v != 1 { + return 0, UnsupportedError("sample format") + } + } + } + return int(tag), nil +} + +// readBits reads n bits from the internal buffer starting at the current offset. +func (d *decoder) readBits(n uint) (v uint32, ok bool) { + for d.nbits < n { + d.v <<= 8 + if d.off >= len(d.buf) { + return 0, false + } + d.v |= uint32(d.buf[d.off]) + d.off++ + d.nbits += 8 + } + d.nbits -= n + rv := d.v >> d.nbits + d.v &^= rv << d.nbits + return rv, true +} + +// flushBits discards the unread bits in the buffer used by readBits. +// It is used at the end of a line. +func (d *decoder) flushBits() { + d.v = 0 + d.nbits = 0 +} + +// minInt returns the smaller of x or y. +func minInt(a, b int) int { + if a <= b { + return a + } + return b +} + +// decode decodes the raw data of an image. +// It reads from d.buf and writes the strip or tile into dst. +func (d *decoder) decode(dst image.Image, xmin, ymin, xmax, ymax int) error { + d.off = 0 + + // Apply horizontal predictor if necessary. + // In this case, p contains the color difference to the preceding pixel. + // See page 64-65 of the spec. + if d.firstVal(tPredictor) == prHorizontal { + switch d.bpp { + case 16: + var off int + n := 2 * len(d.features[tBitsPerSample]) // bytes per sample times samples per pixel + for y := ymin; y < ymax; y++ { + off += n + for x := 0; x < (xmax-xmin-1)*n; x += 2 { + if off+2 > len(d.buf) { + return errNoPixels + } + v0 := d.byteOrder.Uint16(d.buf[off-n : off-n+2]) + v1 := d.byteOrder.Uint16(d.buf[off : off+2]) + d.byteOrder.PutUint16(d.buf[off:off+2], v1+v0) + off += 2 + } + } + case 8: + var off int + n := 1 * len(d.features[tBitsPerSample]) // bytes per sample times samples per pixel + for y := ymin; y < ymax; y++ { + off += n + for x := 0; x < (xmax-xmin-1)*n; x++ { + if off >= len(d.buf) { + return errNoPixels + } + d.buf[off] += d.buf[off-n] + off++ + } + } + case 1: + return UnsupportedError("horizontal predictor with 1 BitsPerSample") + } + } + + rMaxX := minInt(xmax, dst.Bounds().Max.X) + rMaxY := minInt(ymax, dst.Bounds().Max.Y) + switch d.mode { + case mGray, mGrayInvert: + if d.bpp == 16 { + img := dst.(*image.Gray16) + for y := ymin; y < rMaxY; y++ { + for x := xmin; x < rMaxX; x++ { + if d.off+2 > len(d.buf) { + return errNoPixels + } + v := d.byteOrder.Uint16(d.buf[d.off : d.off+2]) + d.off += 2 + if d.mode == mGrayInvert { + v = 0xffff - v + } + img.SetGray16(x, y, color.Gray16{v}) + } + if rMaxX == img.Bounds().Max.X { + d.off += 2 * (xmax - img.Bounds().Max.X) + } + } + } else { + img := dst.(*image.Gray) + max := uint32((1 << d.bpp) - 1) + for y := ymin; y < rMaxY; y++ { + for x := xmin; x < rMaxX; x++ { + v, ok := d.readBits(d.bpp) + if !ok { + return errNoPixels + } + v = v * 0xff / max + if d.mode == mGrayInvert { + v = 0xff - v + } + img.SetGray(x, y, color.Gray{uint8(v)}) + } + d.flushBits() + } + } + case mPaletted: + img := dst.(*image.Paletted) + for y := ymin; y < rMaxY; y++ { + for x := xmin; x < rMaxX; x++ { + v, ok := d.readBits(d.bpp) + if !ok { + return errNoPixels + } + img.SetColorIndex(x, y, uint8(v)) + } + d.flushBits() + } + case mRGB: + if d.bpp == 16 { + img := dst.(*image.RGBA64) + for y := ymin; y < rMaxY; y++ { + for x := xmin; x < rMaxX; x++ { + if d.off+6 > len(d.buf) { + return errNoPixels + } + r := d.byteOrder.Uint16(d.buf[d.off+0 : d.off+2]) + g := d.byteOrder.Uint16(d.buf[d.off+2 : d.off+4]) + b := d.byteOrder.Uint16(d.buf[d.off+4 : d.off+6]) + d.off += 6 + img.SetRGBA64(x, y, color.RGBA64{r, g, b, 0xffff}) + } + } + } else { + img := dst.(*image.RGBA) + for y := ymin; y < rMaxY; y++ { + min := img.PixOffset(xmin, y) + max := img.PixOffset(rMaxX, y) + off := (y - ymin) * (xmax - xmin) * 3 + for i := min; i < max; i += 4 { + if off+3 > len(d.buf) { + return errNoPixels + } + img.Pix[i+0] = d.buf[off+0] + img.Pix[i+1] = d.buf[off+1] + img.Pix[i+2] = d.buf[off+2] + img.Pix[i+3] = 0xff + off += 3 + } + } + } + case mNRGBA: + if d.bpp == 16 { + img := dst.(*image.NRGBA64) + for y := ymin; y < rMaxY; y++ { + for x := xmin; x < rMaxX; x++ { + if d.off+8 > len(d.buf) { + return errNoPixels + } + r := d.byteOrder.Uint16(d.buf[d.off+0 : d.off+2]) + g := d.byteOrder.Uint16(d.buf[d.off+2 : d.off+4]) + b := d.byteOrder.Uint16(d.buf[d.off+4 : d.off+6]) + a := d.byteOrder.Uint16(d.buf[d.off+6 : d.off+8]) + d.off += 8 + img.SetNRGBA64(x, y, color.NRGBA64{r, g, b, a}) + } + } + } else { + img := dst.(*image.NRGBA) + for y := ymin; y < rMaxY; y++ { + min := img.PixOffset(xmin, y) + max := img.PixOffset(rMaxX, y) + i0, i1 := (y-ymin)*(xmax-xmin)*4, (y-ymin+1)*(xmax-xmin)*4 + if i1 > len(d.buf) { + return errNoPixels + } + copy(img.Pix[min:max], d.buf[i0:i1]) + } + } + case mRGBA: + if d.bpp == 16 { + img := dst.(*image.RGBA64) + for y := ymin; y < rMaxY; y++ { + for x := xmin; x < rMaxX; x++ { + if d.off+8 > len(d.buf) { + return errNoPixels + } + r := d.byteOrder.Uint16(d.buf[d.off+0 : d.off+2]) + g := d.byteOrder.Uint16(d.buf[d.off+2 : d.off+4]) + b := d.byteOrder.Uint16(d.buf[d.off+4 : d.off+6]) + a := d.byteOrder.Uint16(d.buf[d.off+6 : d.off+8]) + d.off += 8 + img.SetRGBA64(x, y, color.RGBA64{r, g, b, a}) + } + } + } else { + img := dst.(*image.RGBA) + for y := ymin; y < rMaxY; y++ { + min := img.PixOffset(xmin, y) + max := img.PixOffset(rMaxX, y) + i0, i1 := (y-ymin)*(xmax-xmin)*4, (y-ymin+1)*(xmax-xmin)*4 + if i1 > len(d.buf) { + return errNoPixels + } + copy(img.Pix[min:max], d.buf[i0:i1]) + } + } + } + + return nil +} + +func newDecoder(r io.Reader) (*decoder, error) { + d := &decoder{ + r: newReaderAt(r), + features: make(map[int][]uint), + } + + p := make([]byte, 8) + if _, err := d.r.ReadAt(p, 0); err != nil { + if err == io.EOF { + err = io.ErrUnexpectedEOF + } + return nil, err + } + switch string(p[0:4]) { + case leHeader: + d.byteOrder = binary.LittleEndian + case beHeader: + d.byteOrder = binary.BigEndian + default: + return nil, FormatError("malformed header") + } + + ifdOffset := int64(d.byteOrder.Uint32(p[4:8])) + + // The first two bytes contain the number of entries (12 bytes each). + if _, err := d.r.ReadAt(p[0:2], ifdOffset); err != nil { + return nil, err + } + numItems := int(d.byteOrder.Uint16(p[0:2])) + + // All IFD entries are read in one chunk. + p = make([]byte, ifdLen*numItems) + if _, err := d.r.ReadAt(p, ifdOffset+2); err != nil { + return nil, err + } + + prevTag := -1 + for i := 0; i < len(p); i += ifdLen { + tag, err := d.parseIFD(p[i : i+ifdLen]) + if err != nil { + return nil, err + } + if tag <= prevTag { + return nil, FormatError("tags are not sorted in ascending order") + } + prevTag = tag + } + + d.config.Width = int(d.firstVal(tImageWidth)) + d.config.Height = int(d.firstVal(tImageLength)) + + if _, ok := d.features[tBitsPerSample]; !ok { + // Default is 1 per specification. + d.features[tBitsPerSample] = []uint{1} + } + d.bpp = d.firstVal(tBitsPerSample) + switch d.bpp { + case 0: + return nil, FormatError("BitsPerSample must not be 0") + case 1, 8, 16: + // Nothing to do, these are accepted by this implementation. + default: + return nil, UnsupportedError(fmt.Sprintf("BitsPerSample of %v", d.bpp)) + } + + // Determine the image mode. + switch d.firstVal(tPhotometricInterpretation) { + case pRGB: + if d.bpp == 16 { + for _, b := range d.features[tBitsPerSample] { + if b != 16 { + return nil, FormatError("wrong number of samples for 16bit RGB") + } + } + } else { + for _, b := range d.features[tBitsPerSample] { + if b != 8 { + return nil, FormatError("wrong number of samples for 8bit RGB") + } + } + } + // RGB images normally have 3 samples per pixel. + // If there are more, ExtraSamples (p. 31-32 of the spec) + // gives their meaning (usually an alpha channel). + // + // This implementation does not support extra samples + // of an unspecified type. + switch len(d.features[tBitsPerSample]) { + case 3: + d.mode = mRGB + if d.bpp == 16 { + d.config.ColorModel = color.RGBA64Model + } else { + d.config.ColorModel = color.RGBAModel + } + case 4: + switch d.firstVal(tExtraSamples) { + case 1: + d.mode = mRGBA + if d.bpp == 16 { + d.config.ColorModel = color.RGBA64Model + } else { + d.config.ColorModel = color.RGBAModel + } + case 2: + d.mode = mNRGBA + if d.bpp == 16 { + d.config.ColorModel = color.NRGBA64Model + } else { + d.config.ColorModel = color.NRGBAModel + } + default: + return nil, FormatError("wrong number of samples for RGB") + } + default: + return nil, FormatError("wrong number of samples for RGB") + } + case pPaletted: + d.mode = mPaletted + d.config.ColorModel = color.Palette(d.palette) + case pWhiteIsZero: + d.mode = mGrayInvert + if d.bpp == 16 { + d.config.ColorModel = color.Gray16Model + } else { + d.config.ColorModel = color.GrayModel + } + case pBlackIsZero: + d.mode = mGray + if d.bpp == 16 { + d.config.ColorModel = color.Gray16Model + } else { + d.config.ColorModel = color.GrayModel + } + default: + return nil, UnsupportedError("color model") + } + + return d, nil +} + +// DecodeConfig returns the color model and dimensions of a TIFF image without +// decoding the entire image. +func DecodeConfig(r io.Reader) (image.Config, error) { + d, err := newDecoder(r) + if err != nil { + return image.Config{}, err + } + return d.config, nil +} + +func ccittFillOrder(tiffFillOrder uint) ccitt.Order { + if tiffFillOrder == 2 { + return ccitt.LSB + } + return ccitt.MSB +} + +// Decode reads a TIFF image from r and returns it as an image.Image. +// The type of Image returned depends on the contents of the TIFF. +func Decode(r io.Reader) (img image.Image, err error) { + d, err := newDecoder(r) + if err != nil { + return + } + + blockPadding := false + blockWidth := d.config.Width + blockHeight := d.config.Height + blocksAcross := 1 + blocksDown := 1 + + if d.config.Width == 0 { + blocksAcross = 0 + } + if d.config.Height == 0 { + blocksDown = 0 + } + + var blockOffsets, blockCounts []uint + + if int(d.firstVal(tTileWidth)) != 0 { + blockPadding = true + + blockWidth = int(d.firstVal(tTileWidth)) + blockHeight = int(d.firstVal(tTileLength)) + + if blockWidth != 0 { + blocksAcross = (d.config.Width + blockWidth - 1) / blockWidth + } + if blockHeight != 0 { + blocksDown = (d.config.Height + blockHeight - 1) / blockHeight + } + + blockCounts = d.features[tTileByteCounts] + blockOffsets = d.features[tTileOffsets] + + } else { + if int(d.firstVal(tRowsPerStrip)) != 0 { + blockHeight = int(d.firstVal(tRowsPerStrip)) + } + + if blockHeight != 0 { + blocksDown = (d.config.Height + blockHeight - 1) / blockHeight + } + + blockOffsets = d.features[tStripOffsets] + blockCounts = d.features[tStripByteCounts] + } + + // Check if we have the right number of strips/tiles, offsets and counts. + if n := blocksAcross * blocksDown; len(blockOffsets) < n || len(blockCounts) < n { + return nil, FormatError("inconsistent header") + } + + imgRect := image.Rect(0, 0, d.config.Width, d.config.Height) + switch d.mode { + case mGray, mGrayInvert: + if d.bpp == 16 { + img = image.NewGray16(imgRect) + } else { + img = image.NewGray(imgRect) + } + case mPaletted: + img = image.NewPaletted(imgRect, d.palette) + case mNRGBA: + if d.bpp == 16 { + img = image.NewNRGBA64(imgRect) + } else { + img = image.NewNRGBA(imgRect) + } + case mRGB, mRGBA: + if d.bpp == 16 { + img = image.NewRGBA64(imgRect) + } else { + img = image.NewRGBA(imgRect) + } + } + + for i := 0; i < blocksAcross; i++ { + blkW := blockWidth + if !blockPadding && i == blocksAcross-1 && d.config.Width%blockWidth != 0 { + blkW = d.config.Width % blockWidth + } + for j := 0; j < blocksDown; j++ { + blkH := blockHeight + if !blockPadding && j == blocksDown-1 && d.config.Height%blockHeight != 0 { + blkH = d.config.Height % blockHeight + } + offset := int64(blockOffsets[j*blocksAcross+i]) + n := int64(blockCounts[j*blocksAcross+i]) + switch d.firstVal(tCompression) { + + // According to the spec, Compression does not have a default value, + // but some tools interpret a missing Compression value as none so we do + // the same. + case cNone, 0: + if b, ok := d.r.(*buffer); ok { + d.buf, err = b.Slice(int(offset), int(n)) + } else { + d.buf = make([]byte, n) + _, err = d.r.ReadAt(d.buf, offset) + } + case cG3: + inv := d.firstVal(tPhotometricInterpretation) == pWhiteIsZero + order := ccittFillOrder(d.firstVal(tFillOrder)) + r := ccitt.NewReader(io.NewSectionReader(d.r, offset, n), order, ccitt.Group3, blkW, blkH, &ccitt.Options{Invert: inv, Align: false}) + d.buf, err = ioutil.ReadAll(r) + case cG4: + inv := d.firstVal(tPhotometricInterpretation) == pWhiteIsZero + order := ccittFillOrder(d.firstVal(tFillOrder)) + r := ccitt.NewReader(io.NewSectionReader(d.r, offset, n), order, ccitt.Group4, blkW, blkH, &ccitt.Options{Invert: inv, Align: false}) + d.buf, err = ioutil.ReadAll(r) + case cLZW: + r := lzw.NewReader(io.NewSectionReader(d.r, offset, n), lzw.MSB, 8) + d.buf, err = ioutil.ReadAll(r) + r.Close() + case cDeflate, cDeflateOld: + var r io.ReadCloser + r, err = zlib.NewReader(io.NewSectionReader(d.r, offset, n)) + if err != nil { + return nil, err + } + d.buf, err = ioutil.ReadAll(r) + r.Close() + case cPackBits: + d.buf, err = unpackBits(io.NewSectionReader(d.r, offset, n)) + default: + err = UnsupportedError(fmt.Sprintf("compression value %d", d.firstVal(tCompression))) + } + if err != nil { + return nil, err + } + + xmin := i * blockWidth + ymin := j * blockHeight + xmax := xmin + blkW + ymax := ymin + blkH + err = d.decode(img, xmin, ymin, xmax, ymax) + if err != nil { + return nil, err + } + } + } + return +} + +func init() { + image.RegisterFormat("tiff", leHeader, Decode, DecodeConfig) + image.RegisterFormat("tiff", beHeader, Decode, DecodeConfig) +} diff --git a/vendor/golang.org/x/image/tiff/writer.go b/vendor/golang.org/x/image/tiff/writer.go new file mode 100644 index 00000000..c8a01cea --- /dev/null +++ b/vendor/golang.org/x/image/tiff/writer.go @@ -0,0 +1,438 @@ +// Copyright 2012 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 tiff + +import ( + "bytes" + "compress/zlib" + "encoding/binary" + "image" + "io" + "sort" +) + +// The TIFF format allows to choose the order of the different elements freely. +// The basic structure of a TIFF file written by this package is: +// +// 1. Header (8 bytes). +// 2. Image data. +// 3. Image File Directory (IFD). +// 4. "Pointer area" for larger entries in the IFD. + +// We only write little-endian TIFF files. +var enc = binary.LittleEndian + +// An ifdEntry is a single entry in an Image File Directory. +// A value of type dtRational is composed of two 32-bit values, +// thus data contains two uints (numerator and denominator) for a single number. +type ifdEntry struct { + tag int + datatype int + data []uint32 +} + +func (e ifdEntry) putData(p []byte) { + for _, d := range e.data { + switch e.datatype { + case dtByte, dtASCII: + p[0] = byte(d) + p = p[1:] + case dtShort: + enc.PutUint16(p, uint16(d)) + p = p[2:] + case dtLong, dtRational: + enc.PutUint32(p, uint32(d)) + p = p[4:] + } + } +} + +type byTag []ifdEntry + +func (d byTag) Len() int { return len(d) } +func (d byTag) Less(i, j int) bool { return d[i].tag < d[j].tag } +func (d byTag) Swap(i, j int) { d[i], d[j] = d[j], d[i] } + +func encodeGray(w io.Writer, pix []uint8, dx, dy, stride int, predictor bool) error { + if !predictor { + return writePix(w, pix, dy, dx, stride) + } + buf := make([]byte, dx) + for y := 0; y < dy; y++ { + min := y*stride + 0 + max := y*stride + dx + off := 0 + var v0 uint8 + for i := min; i < max; i++ { + v1 := pix[i] + buf[off] = v1 - v0 + v0 = v1 + off++ + } + if _, err := w.Write(buf); err != nil { + return err + } + } + return nil +} + +func encodeGray16(w io.Writer, pix []uint8, dx, dy, stride int, predictor bool) error { + buf := make([]byte, dx*2) + for y := 0; y < dy; y++ { + min := y*stride + 0 + max := y*stride + dx*2 + off := 0 + var v0 uint16 + for i := min; i < max; i += 2 { + // An image.Gray16's Pix is in big-endian order. + v1 := uint16(pix[i])<<8 | uint16(pix[i+1]) + if predictor { + v0, v1 = v1, v1-v0 + } + // We only write little-endian TIFF files. + buf[off+0] = byte(v1) + buf[off+1] = byte(v1 >> 8) + off += 2 + } + if _, err := w.Write(buf); err != nil { + return err + } + } + return nil +} + +func encodeRGBA(w io.Writer, pix []uint8, dx, dy, stride int, predictor bool) error { + if !predictor { + return writePix(w, pix, dy, dx*4, stride) + } + buf := make([]byte, dx*4) + for y := 0; y < dy; y++ { + min := y*stride + 0 + max := y*stride + dx*4 + off := 0 + var r0, g0, b0, a0 uint8 + for i := min; i < max; i += 4 { + r1, g1, b1, a1 := pix[i+0], pix[i+1], pix[i+2], pix[i+3] + buf[off+0] = r1 - r0 + buf[off+1] = g1 - g0 + buf[off+2] = b1 - b0 + buf[off+3] = a1 - a0 + off += 4 + r0, g0, b0, a0 = r1, g1, b1, a1 + } + if _, err := w.Write(buf); err != nil { + return err + } + } + return nil +} + +func encodeRGBA64(w io.Writer, pix []uint8, dx, dy, stride int, predictor bool) error { + buf := make([]byte, dx*8) + for y := 0; y < dy; y++ { + min := y*stride + 0 + max := y*stride + dx*8 + off := 0 + var r0, g0, b0, a0 uint16 + for i := min; i < max; i += 8 { + // An image.RGBA64's Pix is in big-endian order. + r1 := uint16(pix[i+0])<<8 | uint16(pix[i+1]) + g1 := uint16(pix[i+2])<<8 | uint16(pix[i+3]) + b1 := uint16(pix[i+4])<<8 | uint16(pix[i+5]) + a1 := uint16(pix[i+6])<<8 | uint16(pix[i+7]) + if predictor { + r0, r1 = r1, r1-r0 + g0, g1 = g1, g1-g0 + b0, b1 = b1, b1-b0 + a0, a1 = a1, a1-a0 + } + // We only write little-endian TIFF files. + buf[off+0] = byte(r1) + buf[off+1] = byte(r1 >> 8) + buf[off+2] = byte(g1) + buf[off+3] = byte(g1 >> 8) + buf[off+4] = byte(b1) + buf[off+5] = byte(b1 >> 8) + buf[off+6] = byte(a1) + buf[off+7] = byte(a1 >> 8) + off += 8 + } + if _, err := w.Write(buf); err != nil { + return err + } + } + return nil +} + +func encode(w io.Writer, m image.Image, predictor bool) error { + bounds := m.Bounds() + buf := make([]byte, 4*bounds.Dx()) + for y := bounds.Min.Y; y < bounds.Max.Y; y++ { + off := 0 + if predictor { + var r0, g0, b0, a0 uint8 + for x := bounds.Min.X; x < bounds.Max.X; x++ { + r, g, b, a := m.At(x, y).RGBA() + r1 := uint8(r >> 8) + g1 := uint8(g >> 8) + b1 := uint8(b >> 8) + a1 := uint8(a >> 8) + buf[off+0] = r1 - r0 + buf[off+1] = g1 - g0 + buf[off+2] = b1 - b0 + buf[off+3] = a1 - a0 + off += 4 + r0, g0, b0, a0 = r1, g1, b1, a1 + } + } else { + for x := bounds.Min.X; x < bounds.Max.X; x++ { + r, g, b, a := m.At(x, y).RGBA() + buf[off+0] = uint8(r >> 8) + buf[off+1] = uint8(g >> 8) + buf[off+2] = uint8(b >> 8) + buf[off+3] = uint8(a >> 8) + off += 4 + } + } + if _, err := w.Write(buf); err != nil { + return err + } + } + return nil +} + +// writePix writes the internal byte array of an image to w. It is less general +// but much faster then encode. writePix is used when pix directly +// corresponds to one of the TIFF image types. +func writePix(w io.Writer, pix []byte, nrows, length, stride int) error { + if length == stride { + _, err := w.Write(pix[:nrows*length]) + return err + } + for ; nrows > 0; nrows-- { + if _, err := w.Write(pix[:length]); err != nil { + return err + } + pix = pix[stride:] + } + return nil +} + +func writeIFD(w io.Writer, ifdOffset int, d []ifdEntry) error { + var buf [ifdLen]byte + // Make space for "pointer area" containing IFD entry data + // longer than 4 bytes. + parea := make([]byte, 1024) + pstart := ifdOffset + ifdLen*len(d) + 6 + var o int // Current offset in parea. + + // The IFD has to be written with the tags in ascending order. + sort.Sort(byTag(d)) + + // Write the number of entries in this IFD. + if err := binary.Write(w, enc, uint16(len(d))); err != nil { + return err + } + for _, ent := range d { + enc.PutUint16(buf[0:2], uint16(ent.tag)) + enc.PutUint16(buf[2:4], uint16(ent.datatype)) + count := uint32(len(ent.data)) + if ent.datatype == dtRational { + count /= 2 + } + enc.PutUint32(buf[4:8], count) + datalen := int(count * lengths[ent.datatype]) + if datalen <= 4 { + ent.putData(buf[8:12]) + } else { + if (o + datalen) > len(parea) { + newlen := len(parea) + 1024 + for (o + datalen) > newlen { + newlen += 1024 + } + newarea := make([]byte, newlen) + copy(newarea, parea) + parea = newarea + } + ent.putData(parea[o : o+datalen]) + enc.PutUint32(buf[8:12], uint32(pstart+o)) + o += datalen + } + if _, err := w.Write(buf[:]); err != nil { + return err + } + } + // The IFD ends with the offset of the next IFD in the file, + // or zero if it is the last one (page 14). + if err := binary.Write(w, enc, uint32(0)); err != nil { + return err + } + _, err := w.Write(parea[:o]) + return err +} + +// Options are the encoding parameters. +type Options struct { + // Compression is the type of compression used. + Compression CompressionType + // Predictor determines whether a differencing predictor is used; + // if true, instead of each pixel's color, the color difference to the + // preceding one is saved. This improves the compression for certain + // types of images and compressors. For example, it works well for + // photos with Deflate compression. + Predictor bool +} + +// Encode writes the image m to w. opt determines the options used for +// encoding, such as the compression type. If opt is nil, an uncompressed +// image is written. +func Encode(w io.Writer, m image.Image, opt *Options) error { + d := m.Bounds().Size() + + compression := uint32(cNone) + predictor := false + if opt != nil { + compression = opt.Compression.specValue() + // The predictor field is only used with LZW. See page 64 of the spec. + predictor = opt.Predictor && compression == cLZW + } + + _, err := io.WriteString(w, leHeader) + if err != nil { + return err + } + + // Compressed data is written into a buffer first, so that we + // know the compressed size. + var buf bytes.Buffer + // dst holds the destination for the pixel data of the image -- + // either w or a writer to buf. + var dst io.Writer + // imageLen is the length of the pixel data in bytes. + // The offset of the IFD is imageLen + 8 header bytes. + var imageLen int + + switch compression { + case cNone: + dst = w + // Write IFD offset before outputting pixel data. + switch m.(type) { + case *image.Paletted: + imageLen = d.X * d.Y * 1 + case *image.Gray: + imageLen = d.X * d.Y * 1 + case *image.Gray16: + imageLen = d.X * d.Y * 2 + case *image.RGBA64: + imageLen = d.X * d.Y * 8 + case *image.NRGBA64: + imageLen = d.X * d.Y * 8 + default: + imageLen = d.X * d.Y * 4 + } + err = binary.Write(w, enc, uint32(imageLen+8)) + if err != nil { + return err + } + case cDeflate: + dst = zlib.NewWriter(&buf) + } + + pr := uint32(prNone) + photometricInterpretation := uint32(pRGB) + samplesPerPixel := uint32(4) + bitsPerSample := []uint32{8, 8, 8, 8} + extraSamples := uint32(0) + colorMap := []uint32{} + + if predictor { + pr = prHorizontal + } + switch m := m.(type) { + case *image.Paletted: + photometricInterpretation = pPaletted + samplesPerPixel = 1 + bitsPerSample = []uint32{8} + colorMap = make([]uint32, 256*3) + for i := 0; i < 256 && i < len(m.Palette); i++ { + r, g, b, _ := m.Palette[i].RGBA() + colorMap[i+0*256] = uint32(r) + colorMap[i+1*256] = uint32(g) + colorMap[i+2*256] = uint32(b) + } + err = encodeGray(dst, m.Pix, d.X, d.Y, m.Stride, predictor) + case *image.Gray: + photometricInterpretation = pBlackIsZero + samplesPerPixel = 1 + bitsPerSample = []uint32{8} + err = encodeGray(dst, m.Pix, d.X, d.Y, m.Stride, predictor) + case *image.Gray16: + photometricInterpretation = pBlackIsZero + samplesPerPixel = 1 + bitsPerSample = []uint32{16} + err = encodeGray16(dst, m.Pix, d.X, d.Y, m.Stride, predictor) + case *image.NRGBA: + extraSamples = 2 // Unassociated alpha. + err = encodeRGBA(dst, m.Pix, d.X, d.Y, m.Stride, predictor) + case *image.NRGBA64: + extraSamples = 2 // Unassociated alpha. + bitsPerSample = []uint32{16, 16, 16, 16} + err = encodeRGBA64(dst, m.Pix, d.X, d.Y, m.Stride, predictor) + case *image.RGBA: + extraSamples = 1 // Associated alpha. + err = encodeRGBA(dst, m.Pix, d.X, d.Y, m.Stride, predictor) + case *image.RGBA64: + extraSamples = 1 // Associated alpha. + bitsPerSample = []uint32{16, 16, 16, 16} + err = encodeRGBA64(dst, m.Pix, d.X, d.Y, m.Stride, predictor) + default: + extraSamples = 1 // Associated alpha. + err = encode(dst, m, predictor) + } + if err != nil { + return err + } + + if compression != cNone { + if err = dst.(io.Closer).Close(); err != nil { + return err + } + imageLen = buf.Len() + if err = binary.Write(w, enc, uint32(imageLen+8)); err != nil { + return err + } + if _, err = buf.WriteTo(w); err != nil { + return err + } + } + + ifd := []ifdEntry{ + {tImageWidth, dtShort, []uint32{uint32(d.X)}}, + {tImageLength, dtShort, []uint32{uint32(d.Y)}}, + {tBitsPerSample, dtShort, bitsPerSample}, + {tCompression, dtShort, []uint32{compression}}, + {tPhotometricInterpretation, dtShort, []uint32{photometricInterpretation}}, + {tStripOffsets, dtLong, []uint32{8}}, + {tSamplesPerPixel, dtShort, []uint32{samplesPerPixel}}, + {tRowsPerStrip, dtShort, []uint32{uint32(d.Y)}}, + {tStripByteCounts, dtLong, []uint32{uint32(imageLen)}}, + // There is currently no support for storing the image + // resolution, so give a bogus value of 72x72 dpi. + {tXResolution, dtRational, []uint32{72, 1}}, + {tYResolution, dtRational, []uint32{72, 1}}, + {tResolutionUnit, dtShort, []uint32{resPerInch}}, + } + if pr != prNone { + ifd = append(ifd, ifdEntry{tPredictor, dtShort, []uint32{pr}}) + } + if len(colorMap) != 0 { + ifd = append(ifd, ifdEntry{tColorMap, dtShort, colorMap}) + } + if extraSamples > 0 { + ifd = append(ifd, ifdEntry{tExtraSamples, dtShort, []uint32{extraSamples}}) + } + + return writeIFD(w, imageLen+8, ifd) +} -- cgit v1.2.3