html\
html/template\
image\
- image/bmp\
image/color\
image/draw\
image/gif\
image/jpeg\
image/png\
- image/tiff\
index/suffixarray\
io\
io/ioutil\
exp/ebnflint\
go/doc\
hash\
- image/bmp\
image/gif\
net/http/pprof\
net/http/httptest\
+++ /dev/null
-# 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.
-
-include ../../../Make.inc
-
-TARG=image/bmp
-GOFILES=\
- reader.go\
-
-include ../../../Make.pkg
+++ /dev/null
-// 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.
-//
-// The BMP specification is at http://www.digicamsoft.com/bmp/bmp.html.
-package 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.
-func decodePaletted(r io.Reader, c image.Config) (image.Image, error) {
- var tmp [4]byte
- paletted := image.NewPaletted(image.Rect(0, 0, c.Width, c.Height), c.ColorModel.(color.Palette))
- // BMP images are stored bottom-up rather than top-down.
- for y := c.Height - 1; y >= 0; y-- {
- p := paletted.Pix[y*paletted.Stride : y*paletted.Stride+c.Width]
- _, err := io.ReadFull(r, p)
- if 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
-}
-
-// decodeRGBA reads a 24 bit-per-pixel BMP image from r.
-func decodeRGBA(r io.Reader, c image.Config) (image.Image, error) {
- rgba := image.NewRGBA(image.Rect(0, 0, c.Width, c.Height))
- // There are 3 bytes per pixel, and each row is 4-byte aligned.
- b := make([]byte, (3*c.Width+3)&^3)
- // BMP images are stored bottom-up rather than top-down.
- for y := c.Height - 1; y >= 0; y-- {
- _, err := io.ReadFull(r, b)
- if 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
-}
-
-// Decode reads a BMP image from r and returns it as an image.Image.
-// Limitation: The file must be 8 or 24 bits per pixel.
-func Decode(r io.Reader) (image.Image, error) {
- c, err := DecodeConfig(r)
- if err != nil {
- return nil, err
- }
- if c.ColorModel == color.RGBAModel {
- return decodeRGBA(r, c)
- }
- return decodePaletted(r, c)
-}
-
-// DecodeConfig returns the color model and dimensions of a BMP image without
-// decoding the entire image.
-// Limitation: The file must be 8 or 24 bits per pixel.
-func DecodeConfig(r io.Reader) (config image.Config, err error) {
- // We only support those BMP images that are a BITMAPFILEHEADER
- // immediately followed by a BITMAPINFOHEADER.
- const (
- fileHeaderLen = 14
- infoHeaderLen = 40
- )
- var b [1024]byte
- if _, err = io.ReadFull(r, b[:fileHeaderLen+infoHeaderLen]); err != nil {
- return
- }
- if string(b[:2]) != "BM" {
- err = errors.New("bmp: invalid format")
- return
- }
- offset := readUint32(b[10:14])
- if readUint32(b[14:18]) != infoHeaderLen {
- err = ErrUnsupported
- return
- }
- width := int(readUint32(b[18:22]))
- height := int(readUint32(b[22:26]))
- if width < 0 || height < 0 {
- err = ErrUnsupported
- return
- }
- // We only support 1 plane, 8 or 24 bits per pixel and no compression.
- planes, bpp, compression := readUint16(b[26:28]), readUint16(b[28:30]), readUint32(b[30:34])
- if planes != 1 || compression != 0 {
- err = ErrUnsupported
- return
- }
- switch bpp {
- case 8:
- if offset != fileHeaderLen+infoHeaderLen+256*4 {
- err = ErrUnsupported
- return
- }
- _, err = io.ReadFull(r, b[:256*4])
- if err != nil {
- return
- }
- 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{pcm, width, height}, nil
- case 24:
- if offset != fileHeaderLen+infoHeaderLen {
- err = ErrUnsupported
- return
- }
- return image.Config{color.RGBAModel, width, height}, nil
- }
- err = ErrUnsupported
- return
-}
-
-func init() {
- image.RegisterFormat("bmp", "BM????\x00\x00\x00\x00", Decode, DecodeConfig)
-}
"os"
"testing"
- _ "image/bmp"
_ "image/gif"
_ "image/jpeg"
_ "image/png"
- _ "image/tiff"
)
type imageTest struct {
}
var imageTests = []imageTest{
- {"testdata/video-001.png", "testdata/video-001.bmp", 0},
+ {"testdata/video-001.png", "testdata/video-001.png", 0},
// GIF images are restricted to a 256-color palette and the conversion
// to GIF loses significant image quality.
{"testdata/video-001.png", "testdata/video-001.gif", 64 << 8},
{"testdata/video-001.png", "testdata/video-001.5bpp.gif", 128 << 8},
// JPEG is a lossy format and hence needs a non-zero tolerance.
{"testdata/video-001.png", "testdata/video-001.jpeg", 8 << 8},
- {"testdata/video-001.png", "testdata/video-001.png", 0},
- {"testdata/video-001.png", "testdata/video-001.tiff", 0},
-
- // Test grayscale images.
+ // Grayscale images.
{"testdata/video-005.gray.png", "testdata/video-005.gray.jpeg", 8 << 8},
{"testdata/video-005.gray.png", "testdata/video-005.gray.png", 0},
}
+++ /dev/null
-# 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.
-
-include ../../../Make.inc
-
-TARG=image/tiff
-GOFILES=\
- buffer.go\
- compress.go\
- consts.go\
- reader.go\
-
-include ../../../Make.pkg
+++ /dev/null
-// 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
-}
-
-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
- }
-
- 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 copy(p, b.buf[o:end]), err
- }
- }
-
- return copy(p, b.buf[o: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),
- }
-}
+++ /dev/null
-// 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"
- "strings"
- "testing"
-)
-
-var readAtTests = []struct {
- n int
- off int64
- s string
- err error
-}{
- {2, 0, "ab", nil},
- {6, 0, "abcdef", nil},
- {3, 3, "def", nil},
- {3, 5, "f", io.EOF},
- {3, 6, "", io.EOF},
-}
-
-func TestReadAt(t *testing.T) {
- r := newReaderAt(strings.NewReader("abcdef"))
- b := make([]byte, 10)
- for _, test := range readAtTests {
- n, err := r.ReadAt(b[:test.n], test.off)
- s := string(b[:n])
- if s != test.s || err != test.err {
- t.Errorf("buffer.ReadAt(<%v bytes>, %v): got %v, %q; want %v, %q", test.n, test.off, err, s, test.err, test.s)
- }
- }
-}
+++ /dev/null
-// 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]...)
- }
- }
- panic("unreachable")
-}
+++ /dev/null
-// 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
-
- tStripOffsets = 273
- tSamplesPerPixel = 277
- tRowsPerStrip = 278
- tStripByteCounts = 279
-
- 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
-)
-
-// imageMode represents the mode of the image.
-type imageMode int
-
-const (
- mBilevel imageMode = iota
- mPaletted
- mGray
- mGrayInvert
- mRGB
- mRGBA
- mNRGBA
-)
+++ /dev/null
-// 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.
-//
-// The TIFF specification is at http://partners.adobe.com/public/developer/en/tiff/TIFF6.pdf
-package tiff
-
-import (
- "compress/lzw"
- "compress/zlib"
- "encoding/binary"
- "image"
- "image/color"
- "io"
- "io/ioutil"
-)
-
-// 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)
-}
-
-// An InternalError reports that an internal error was encountered.
-type InternalError string
-
-func (e InternalError) Error() string {
- return "tiff: internal error: " + string(e)
-}
-
-type decoder struct {
- r io.ReaderAt
- byteOrder binary.ByteOrder
- config image.Config
- mode imageMode
- 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
- datatype := d.byteOrder.Uint16(p[2:4])
- count := d.byteOrder.Uint32(p[4:8])
- 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 the IFD entry in p is "interesting" and
-// stows away the data in the decoder.
-func (d *decoder) parseIFD(p []byte) error {
- tag := d.byteOrder.Uint16(p[0:2])
- switch tag {
- case tBitsPerSample,
- tExtraSamples,
- tPhotometricInterpretation,
- tCompression,
- tPredictor,
- tStripOffsets,
- tStripByteCounts,
- tRowsPerStrip,
- tImageLength,
- tImageWidth:
- val, err := d.ifdUint(p)
- if err != nil {
- return err
- }
- d.features[int(tag)] = val
- case tColorMap:
- val, err := d.ifdUint(p)
- if err != nil {
- return err
- }
- numcolors := len(val) / 3
- if len(val)%3 != 0 || numcolors <= 0 || numcolors > 256 {
- return 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 err
- }
- for _, v := range val {
- if v != 1 {
- return UnsupportedError("sample format")
- }
- }
- }
- return nil
-}
-
-// readBits reads n bits from the internal buffer starting at the current offset.
-func (d *decoder) readBits(n uint) uint32 {
- for d.nbits < n {
- d.v <<= 8
- 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
-}
-
-// 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
-}
-
-// decode decodes the raw data of an image.
-// It reads from d.buf and writes the strip with ymin <= y < ymax into dst.
-func (d *decoder) decode(dst image.Image, ymin, 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 && d.firstVal(tBitsPerSample) == 8 {
- var off int
- spp := len(d.features[tBitsPerSample]) // samples per pixel
- for y := ymin; y < ymax; y++ {
- off += spp
- for x := 0; x < (dst.Bounds().Dx()-1)*spp; x++ {
- d.buf[off] += d.buf[off-spp]
- off++
- }
- }
- }
-
- switch d.mode {
- case mGray, mGrayInvert:
- img := dst.(*image.Gray)
- bpp := d.firstVal(tBitsPerSample)
- max := uint32((1 << bpp) - 1)
- for y := ymin; y < ymax; y++ {
- for x := img.Rect.Min.X; x < img.Rect.Max.X; x++ {
- v := uint8(d.readBits(bpp) * 0xff / max)
- if d.mode == mGrayInvert {
- v = 0xff - v
- }
- img.SetGray(x, y, color.Gray{v})
- }
- d.flushBits()
- }
- case mPaletted:
- img := dst.(*image.Paletted)
- bpp := d.firstVal(tBitsPerSample)
- for y := ymin; y < ymax; y++ {
- for x := img.Rect.Min.X; x < img.Rect.Max.X; x++ {
- img.SetColorIndex(x, y, uint8(d.readBits(bpp)))
- }
- d.flushBits()
- }
- case mRGB:
- img := dst.(*image.RGBA)
- min := img.PixOffset(0, ymin)
- max := img.PixOffset(0, ymax)
- var off int
- for i := min; i < max; i += 4 {
- 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:
- img := dst.(*image.NRGBA)
- min := img.PixOffset(0, ymin)
- max := img.PixOffset(0, ymax)
- if len(d.buf) != max-min {
- return FormatError("short data strip")
- }
- copy(img.Pix[min:max], d.buf)
- case mRGBA:
- img := dst.(*image.RGBA)
- min := img.PixOffset(0, ymin)
- max := img.PixOffset(0, ymax)
- if len(d.buf) != max-min {
- return FormatError("short data strip")
- }
- copy(img.Pix[min:max], d.buf)
- }
-
- 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 {
- 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
- }
-
- for i := 0; i < len(p); i += ifdLen {
- if err := d.parseIFD(p[i : i+ifdLen]); err != nil {
- return nil, err
- }
- }
-
- d.config.Width = int(d.firstVal(tImageWidth))
- d.config.Height = int(d.firstVal(tImageLength))
-
- if _, ok := d.features[tBitsPerSample]; !ok {
- return nil, FormatError("BitsPerSample tag missing")
- }
-
- // Determine the image mode.
- switch d.firstVal(tPhotometricInterpretation) {
- case pRGB:
- for _, b := range d.features[tBitsPerSample] {
- if b != 8 {
- return nil, UnsupportedError("non-8-bit RGB image")
- }
- }
- d.config.ColorModel = color.RGBAModel
- // 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
- case 4:
- switch d.firstVal(tExtraSamples) {
- case 1:
- d.mode = mRGBA
- case 2:
- d.mode = mNRGBA
- 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
- d.config.ColorModel = color.GrayModel
- case pBlackIsZero:
- d.mode = mGray
- 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
-}
-
-// 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
- }
-
- // Check if we have the right number of strips, offsets and counts.
- rps := int(d.firstVal(tRowsPerStrip))
- if rps == 0 {
- // Assume only one strip.
- rps = d.config.Height
- }
- numStrips := (d.config.Height + rps - 1) / rps
- if rps == 0 || len(d.features[tStripOffsets]) < numStrips || len(d.features[tStripByteCounts]) < numStrips {
- return nil, FormatError("inconsistent header")
- }
-
- switch d.mode {
- case mGray, mGrayInvert:
- img = image.NewGray(image.Rect(0, 0, d.config.Width, d.config.Height))
- case mPaletted:
- img = image.NewPaletted(image.Rect(0, 0, d.config.Width, d.config.Height), d.palette)
- case mNRGBA:
- img = image.NewNRGBA(image.Rect(0, 0, d.config.Width, d.config.Height))
- case mRGB, mRGBA:
- img = image.NewRGBA(image.Rect(0, 0, d.config.Width, d.config.Height))
- }
-
- for i := 0; i < numStrips; i++ {
- ymin := i * rps
- // The last strip may be shorter.
- if i == numStrips-1 && d.config.Height%rps != 0 {
- rps = d.config.Height % rps
- }
- offset := int64(d.features[tStripOffsets][i])
- n := int64(d.features[tStripByteCounts][i])
- switch d.firstVal(tCompression) {
- case cNone:
- // TODO(bsiegert): Avoid copy if r is a tiff.buffer.
- d.buf = make([]byte, n)
- _, err = d.r.ReadAt(d.buf, offset)
- 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:
- 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("compression")
- }
- if err != nil {
- return
- }
- err = d.decode(img, ymin, ymin+rps)
- }
- return
-}
-
-func init() {
- image.RegisterFormat("tiff", leHeader, Decode, DecodeConfig)
- image.RegisterFormat("tiff", beHeader, Decode, DecodeConfig)
-}
+++ /dev/null
-// 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 (
- "image"
- "io/ioutil"
- "os"
- "strings"
- "testing"
-)
-
-// Read makes *buffer implements io.Reader, so that we can pass one to Decode.
-func (*buffer) Read([]byte) (int, error) {
- panic("unimplemented")
-}
-
-// TestNoRPS tries to decode an image that has no RowsPerStrip tag.
-// The tag is mandatory according to the spec but some software omits
-// it in the case of a single strip.
-func TestNoRPS(t *testing.T) {
- f, err := os.Open("testdata/no_rps.tiff")
- if err != nil {
- t.Fatal(err)
- }
- defer f.Close()
- _, err = Decode(f)
- if err != nil {
- t.Fatal(err)
- }
-}
-
-// TestUnpackBits tests the decoding of PackBits-encoded data.
-func TestUnpackBits(t *testing.T) {
- var unpackBitsTests = []struct {
- compressed string
- uncompressed string
- }{{
- // Example data from Wikipedia.
- "\xfe\xaa\x02\x80\x00\x2a\xfd\xaa\x03\x80\x00\x2a\x22\xf7\xaa",
- "\xaa\xaa\xaa\x80\x00\x2a\xaa\xaa\xaa\xaa\x80\x00\x2a\x22\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa\xaa",
- }}
- for _, u := range unpackBitsTests {
- buf, err := unpackBits(strings.NewReader(u.compressed))
- if err != nil {
- t.Fatal(err)
- }
- if string(buf) != u.uncompressed {
- t.Fatalf("unpackBits: want %x, got %x", u.uncompressed, buf)
- }
- }
-}
-
-// TestDecompress tests that decoding some TIFF images that use different
-// compression formats result in the same pixel data.
-func TestDecompress(t *testing.T) {
- var decompressTests = []string{
- "bw-uncompressed.tiff",
- "bw-deflate.tiff",
- "bw-packbits.tiff",
- }
- var img0 image.Image
- for _, name := range decompressTests {
- f, err := os.Open("testdata/" + name)
- if err != nil {
- t.Fatal(err)
- }
- defer f.Close()
- if img0 == nil {
- img0, err = Decode(f)
- if err != nil {
- t.Fatalf("decoding %s: %v", name, err)
- }
- continue
- }
-
- img1, err := Decode(f)
- if err != nil {
- t.Fatalf("decoding %s: %v", name, err)
- }
- b := img1.Bounds()
- // Compare images.
- if !b.Eq(img0.Bounds()) {
- t.Fatalf("wrong image size: want %s, got %s", img0.Bounds(), b)
- }
- for y := b.Min.Y; y < b.Max.Y; y++ {
- for x := b.Min.X; x < b.Max.X; x++ {
- c0 := img0.At(x, y)
- c1 := img1.At(x, y)
- r0, g0, b0, a0 := c0.RGBA()
- r1, g1, b1, a1 := c1.RGBA()
- if r0 != r1 || g0 != g1 || b0 != b1 || a0 != a1 {
- t.Fatalf("pixel at (%d, %d) has wrong color: want %v, got %v", x, y, c0, c1)
- }
- }
- }
- }
-}
-
-const filename = "testdata/video-001-uncompressed.tiff"
-
-// BenchmarkDecode benchmarks the decoding of an image.
-func BenchmarkDecode(b *testing.B) {
- b.StopTimer()
- contents, err := ioutil.ReadFile(filename)
- if err != nil {
- panic(err)
- }
- r := &buffer{buf: contents}
- b.StartTimer()
- for i := 0; i < b.N; i++ {
- _, err := Decode(r)
- if err != nil {
- b.Fatal("Decode:", err)
- }
- }
-}
