From 61e27beabc9804fdcf59ed9df2180802175a4f70 Mon Sep 17 00:00:00 2001 From: Christopher Speller Date: Tue, 28 Aug 2018 10:05:26 -0700 Subject: Updating dependancies. (#9303) --- vendor/github.com/disintegration/imaging/io.go | 463 +++++++++++++++++++++++++ 1 file changed, 463 insertions(+) create mode 100644 vendor/github.com/disintegration/imaging/io.go (limited to 'vendor/github.com/disintegration/imaging/io.go') diff --git a/vendor/github.com/disintegration/imaging/io.go b/vendor/github.com/disintegration/imaging/io.go new file mode 100644 index 000000000..557bf2f3d --- /dev/null +++ b/vendor/github.com/disintegration/imaging/io.go @@ -0,0 +1,463 @@ +package imaging + +import ( + "encoding/binary" + "errors" + "image" + "image/draw" + "image/gif" + "image/jpeg" + "image/png" + "io" + "io/ioutil" + "os" + "path/filepath" + "strings" + + "golang.org/x/image/bmp" + "golang.org/x/image/tiff" +) + +// Format is an image file format. +type Format int + +// Image file formats. +const ( + JPEG Format = iota + PNG + GIF + TIFF + BMP +) + +func (f Format) String() string { + switch f { + case JPEG: + return "JPEG" + case PNG: + return "PNG" + case GIF: + return "GIF" + case TIFF: + return "TIFF" + case BMP: + return "BMP" + default: + return "Unsupported" + } +} + +var formatFromExt = map[string]Format{ + "jpg": JPEG, + "jpeg": JPEG, + "png": PNG, + "tif": TIFF, + "tiff": TIFF, + "bmp": BMP, + "gif": GIF, +} + +// FormatFromExtension parses image format from extension: +// "jpg" (or "jpeg"), "png", "gif", "tif" (or "tiff") and "bmp" are supported. +func FormatFromExtension(ext string) (Format, error) { + if f, ok := formatFromExt[strings.ToLower(strings.TrimPrefix(ext, "."))]; ok { + return f, nil + } + return -1, ErrUnsupportedFormat +} + +// FormatFromFilename parses image format from filename extension: +// "jpg" (or "jpeg"), "png", "gif", "tif" (or "tiff") and "bmp" are supported. +func FormatFromFilename(filename string) (Format, error) { + ext := filepath.Ext(filename) + return FormatFromExtension(ext) +} + +var ( + // ErrUnsupportedFormat means the given image format (or file extension) is unsupported. + ErrUnsupportedFormat = errors.New("imaging: unsupported image format") +) + +type fileSystem interface { + Create(string) (io.WriteCloser, error) + Open(string) (io.ReadCloser, error) +} + +type localFS struct{} + +func (localFS) Create(name string) (io.WriteCloser, error) { return os.Create(name) } +func (localFS) Open(name string) (io.ReadCloser, error) { return os.Open(name) } + +var fs fileSystem = localFS{} + +type decodeConfig struct { + autoOrientation bool +} + +var defaultDecodeConfig = decodeConfig{ + autoOrientation: false, +} + +// DecodeOption sets an optional parameter for the Decode and Open functions. +type DecodeOption func(*decodeConfig) + +// AutoOrientation returns a DecodeOption that sets the auto-orientation mode. +// If auto-orientation is enabled, the image will be transformed after decoding +// according to the EXIF orientation tag (if present). By default it's disabled. +func AutoOrientation(enabled bool) DecodeOption { + return func(c *decodeConfig) { + c.autoOrientation = enabled + } +} + +// Decode reads an image from r. +func Decode(r io.Reader, opts ...DecodeOption) (image.Image, error) { + cfg := defaultDecodeConfig + for _, option := range opts { + option(&cfg) + } + + if !cfg.autoOrientation { + img, _, err := image.Decode(r) + return img, err + } + + var orient orientation + pr, pw := io.Pipe() + r = io.TeeReader(r, pw) + done := make(chan struct{}) + go func() { + defer close(done) + orient = readOrientation(pr) + io.Copy(ioutil.Discard, pr) + }() + + img, _, err := image.Decode(r) + pw.Close() + <-done + if err != nil { + return nil, err + } + + return fixOrientation(img, orient), nil +} + +// Open loads an image from file. +// +// Examples: +// +// // Load an image from file. +// img, err := imaging.Open("test.jpg") +// +// // Load an image and transform it depending on the EXIF orientation tag (if present). +// img, err := imaging.Open("test.jpg", imaging.AutoOrientation(true)) +// +func Open(filename string, opts ...DecodeOption) (image.Image, error) { + file, err := fs.Open(filename) + if err != nil { + return nil, err + } + defer file.Close() + return Decode(file, opts...) +} + +type encodeConfig struct { + jpegQuality int + gifNumColors int + gifQuantizer draw.Quantizer + gifDrawer draw.Drawer + pngCompressionLevel png.CompressionLevel +} + +var defaultEncodeConfig = encodeConfig{ + jpegQuality: 95, + gifNumColors: 256, + gifQuantizer: nil, + gifDrawer: nil, + pngCompressionLevel: png.DefaultCompression, +} + +// EncodeOption sets an optional parameter for the Encode and Save functions. +type EncodeOption func(*encodeConfig) + +// JPEGQuality returns an EncodeOption that sets the output JPEG quality. +// Quality ranges from 1 to 100 inclusive, higher is better. Default is 95. +func JPEGQuality(quality int) EncodeOption { + return func(c *encodeConfig) { + c.jpegQuality = quality + } +} + +// GIFNumColors returns an EncodeOption that sets the maximum number of colors +// used in the GIF-encoded image. It ranges from 1 to 256. Default is 256. +func GIFNumColors(numColors int) EncodeOption { + return func(c *encodeConfig) { + c.gifNumColors = numColors + } +} + +// GIFQuantizer returns an EncodeOption that sets the quantizer that is used to produce +// a palette of the GIF-encoded image. +func GIFQuantizer(quantizer draw.Quantizer) EncodeOption { + return func(c *encodeConfig) { + c.gifQuantizer = quantizer + } +} + +// GIFDrawer returns an EncodeOption that sets the drawer that is used to convert +// the source image to the desired palette of the GIF-encoded image. +func GIFDrawer(drawer draw.Drawer) EncodeOption { + return func(c *encodeConfig) { + c.gifDrawer = drawer + } +} + +// PNGCompressionLevel returns an EncodeOption that sets the compression level +// of the PNG-encoded image. Default is png.DefaultCompression. +func PNGCompressionLevel(level png.CompressionLevel) EncodeOption { + return func(c *encodeConfig) { + c.pngCompressionLevel = level + } +} + +// Encode writes the image img to w in the specified format (JPEG, PNG, GIF, TIFF or BMP). +func Encode(w io.Writer, img image.Image, format Format, opts ...EncodeOption) error { + cfg := defaultEncodeConfig + for _, option := range opts { + option(&cfg) + } + + var err error + switch format { + case JPEG: + var rgba *image.RGBA + if nrgba, ok := img.(*image.NRGBA); ok { + if nrgba.Opaque() { + rgba = &image.RGBA{ + Pix: nrgba.Pix, + Stride: nrgba.Stride, + Rect: nrgba.Rect, + } + } + } + if rgba != nil { + err = jpeg.Encode(w, rgba, &jpeg.Options{Quality: cfg.jpegQuality}) + } else { + err = jpeg.Encode(w, img, &jpeg.Options{Quality: cfg.jpegQuality}) + } + + case PNG: + enc := png.Encoder{CompressionLevel: cfg.pngCompressionLevel} + err = enc.Encode(w, img) + + case GIF: + err = gif.Encode(w, img, &gif.Options{ + NumColors: cfg.gifNumColors, + Quantizer: cfg.gifQuantizer, + Drawer: cfg.gifDrawer, + }) + + case TIFF: + err = tiff.Encode(w, img, &tiff.Options{Compression: tiff.Deflate, Predictor: true}) + + case BMP: + err = bmp.Encode(w, img) + + default: + err = ErrUnsupportedFormat + } + return err +} + +// Save saves the image to file with the specified filename. +// The format is determined from the filename extension: +// "jpg" (or "jpeg"), "png", "gif", "tif" (or "tiff") and "bmp" are supported. +// +// Examples: +// +// // Save the image as PNG. +// err := imaging.Save(img, "out.png") +// +// // Save the image as JPEG with optional quality parameter set to 80. +// err := imaging.Save(img, "out.jpg", imaging.JPEGQuality(80)) +// +func Save(img image.Image, filename string, opts ...EncodeOption) (err error) { + f, err := FormatFromFilename(filename) + if err != nil { + return err + } + file, err := fs.Create(filename) + if err != nil { + return err + } + + defer func() { + cerr := file.Close() + if err == nil { + err = cerr + } + }() + + return Encode(file, img, f, opts...) +} + +// orientation is an EXIF flag that specifies the transformation +// that should be applied to image to display it correctly. +type orientation int + +const ( + orientationUnspecified = 0 + orientationNormal = 1 + orientationFlipH = 2 + orientationRotate180 = 3 + orientationFlipV = 4 + orientationTranspose = 5 + orientationRotate270 = 6 + orientationTransverse = 7 + orientationRotate90 = 8 +) + +// readOrientation tries to read the orientation EXIF flag from image data in r. +// If the EXIF data block is not found or the orientation flag is not found +// or any other error occures while reading the data, it returns the +// orientationUnspecified (0) value. +func readOrientation(r io.Reader) orientation { + const ( + markerSOI = 0xffd8 + markerAPP1 = 0xffe1 + exifHeader = 0x45786966 + byteOrderBE = 0x4d4d + byteOrderLE = 0x4949 + orientationTag = 0x0112 + ) + + // Check if JPEG SOI marker is present. + var soi uint16 + if err := binary.Read(r, binary.BigEndian, &soi); err != nil { + return orientationUnspecified + } + if soi != markerSOI { + return orientationUnspecified // Missing JPEG SOI marker. + } + + // Find JPEG APP1 marker. + for { + var marker, size uint16 + if err := binary.Read(r, binary.BigEndian, &marker); err != nil { + return orientationUnspecified + } + if err := binary.Read(r, binary.BigEndian, &size); err != nil { + return orientationUnspecified + } + if marker>>8 != 0xff { + return orientationUnspecified // Invalid JPEG marker. + } + if marker == markerAPP1 { + break + } + if size < 2 { + return orientationUnspecified // Invalid block size. + } + if _, err := io.CopyN(ioutil.Discard, r, int64(size-2)); err != nil { + return orientationUnspecified + } + } + + // Check if EXIF header is present. + var header uint32 + if err := binary.Read(r, binary.BigEndian, &header); err != nil { + return orientationUnspecified + } + if header != exifHeader { + return orientationUnspecified + } + if _, err := io.CopyN(ioutil.Discard, r, 2); err != nil { + return orientationUnspecified + } + + // Read byte order information. + var ( + byteOrderTag uint16 + byteOrder binary.ByteOrder + ) + if err := binary.Read(r, binary.BigEndian, &byteOrderTag); err != nil { + return orientationUnspecified + } + switch byteOrderTag { + case byteOrderBE: + byteOrder = binary.BigEndian + case byteOrderLE: + byteOrder = binary.LittleEndian + default: + return orientationUnspecified // Invalid byte order flag. + } + if _, err := io.CopyN(ioutil.Discard, r, 2); err != nil { + return orientationUnspecified + } + + // Skip the EXIF offset. + var offset uint32 + if err := binary.Read(r, byteOrder, &offset); err != nil { + return orientationUnspecified + } + if offset < 8 { + return orientationUnspecified // Invalid offset value. + } + if _, err := io.CopyN(ioutil.Discard, r, int64(offset-8)); err != nil { + return orientationUnspecified + } + + // Read the number of tags. + var numTags uint16 + if err := binary.Read(r, byteOrder, &numTags); err != nil { + return orientationUnspecified + } + + // Find the orientation tag. + for i := 0; i < int(numTags); i++ { + var tag uint16 + if err := binary.Read(r, byteOrder, &tag); err != nil { + return orientationUnspecified + } + if tag != orientationTag { + if _, err := io.CopyN(ioutil.Discard, r, 10); err != nil { + return orientationUnspecified + } + continue + } + if _, err := io.CopyN(ioutil.Discard, r, 6); err != nil { + return orientationUnspecified + } + var val uint16 + if err := binary.Read(r, byteOrder, &val); err != nil { + return orientationUnspecified + } + if val < 1 || val > 8 { + return orientationUnspecified // Invalid tag value. + } + return orientation(val) + } + return orientationUnspecified // Missing orientation tag. +} + +// fixOrientation applies a transform to img corresponding to the given orientation flag. +func fixOrientation(img image.Image, o orientation) image.Image { + switch o { + case orientationNormal: + case orientationFlipH: + img = FlipH(img) + case orientationFlipV: + img = FlipV(img) + case orientationRotate90: + img = Rotate90(img) + case orientationRotate180: + img = Rotate180(img) + case orientationRotate270: + img = Rotate270(img) + case orientationTranspose: + img = Transpose(img) + case orientationTransverse: + img = Transverse(img) + } + return img +} -- cgit v1.2.3-1-g7c22