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Diffstat (limited to 'WebCore/platform/image-decoders/skia/BMPImageReader.h')
| -rw-r--r-- | WebCore/platform/image-decoders/skia/BMPImageReader.h | 327 |
1 files changed, 0 insertions, 327 deletions
diff --git a/WebCore/platform/image-decoders/skia/BMPImageReader.h b/WebCore/platform/image-decoders/skia/BMPImageReader.h deleted file mode 100644 index 0edf7b0..0000000 --- a/WebCore/platform/image-decoders/skia/BMPImageReader.h +++ /dev/null @@ -1,327 +0,0 @@ -/* - * Copyright (c) 2008, 2009, Google Inc. All rights reserved. - * - * Redistribution and use in source and binary forms, with or without - * modification, are permitted provided that the following conditions are - * met: - * - * * Redistributions of source code must retain the above copyright - * notice, this list of conditions and the following disclaimer. - * * Redistributions in binary form must reproduce the above - * copyright notice, this list of conditions and the following disclaimer - * in the documentation and/or other materials provided with the - * distribution. - * * Neither the name of Google Inc. nor the names of its - * contributors may be used to endorse or promote products derived from - * this software without specific prior written permission. - * - * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT - * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, - * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT - * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, - * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY - * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT - * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE - * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. - */ - -#ifndef BMPImageReader_h -#define BMPImageReader_h - -#include <stdint.h> -#include "ImageDecoder.h" - -namespace WebCore { - - // This class decodes a BMP image. It is used as a base for the BMP and ICO - // decoders, which wrap it in the appropriate code to read file headers, etc. - class BMPImageReader : public ImageDecoder { - public: - BMPImageReader(); - - // Does the actual decoding. |data| starts at the beginning of the file, - // but may be incomplete. - virtual void decodeImage(SharedBuffer* data) = 0; - - // ImageDecoder - virtual void setData(SharedBuffer* data, bool allDataReceived); - virtual RGBA32Buffer* frameBufferAtIndex(size_t index); - - protected: - enum AndMaskState { - None, - NotYetDecoded, - Decoding, - }; - - // Decodes a single BMP, starting with an info header. - void decodeBMP(SharedBuffer* data); - - // Read a value from |data[m_decodedOffset + additionalOffset]|, converting - // from little to native endianness. - inline uint16_t readUint16(SharedBuffer* data, int additionalOffset) const - { - uint16_t result; - memcpy(&result, &data->data()[m_decodedOffset + additionalOffset], 2); - #if PLATFORM(BIG_ENDIAN) - result = ((result & 0xff) << 8) | ((result & 0xff00) >> 8); - #endif - return result; - } - - inline uint32_t readUint32(SharedBuffer* data, int additionalOffset) const - { - uint32_t result; - memcpy(&result, &data->data()[m_decodedOffset + additionalOffset], 4); - #if PLATFORM(BIG_ENDIAN) - result = ((result & 0xff) << 24) | ((result & 0xff00) << 8) | - ((result & 0xff0000) >> 8) | ((result & 0xff000000) >> 24); - #endif - return result; - } - - // An index into |m_data| representing how much we've already decoded. - size_t m_decodedOffset; - - // The file offset at which the BMP info header starts. - size_t m_headerOffset; - - // The file offset at which the actual image bits start. When decoding ICO - // files, this is set to 0, since it's not stored anywhere in a header; the - // reader functions expect the image data to start immediately after the - // header and (if necessary) color table. - size_t m_imgDataOffset; - - // ICOs store a 1bpp "mask" immediately after the main bitmap image data - // (and, confusingly, add its height to the biHeight value in the info - // header, thus doubling it). This variable tracks whether we have such a - // mask and if we've started decoding it yet. - AndMaskState m_andMaskState; - - private: - // The various BMP compression types. We don't currently decode all these. - enum CompressionType { - // Universal types - RGB = 0, - RLE8 = 1, - RLE4 = 2, - // Windows V3+ only - BITFIELDS = 3, - JPEG = 4, - PNG = 5, - // OS/2 2.x-only - HUFFMAN1D, // Stored in file as 3 - RLE24, // Stored in file as 4 - }; - - // These are based on the Windows BITMAPINFOHEADER and RGBTRIPLE structs, - // but with unnecessary entries removed. - struct BitmapInfoHeader { - uint32_t biSize; - int32_t biWidth; - int32_t biHeight; - uint16_t biBitCount; - CompressionType biCompression; - uint32_t biClrUsed; - }; - struct RGBTriple { - uint8_t rgbBlue; - uint8_t rgbGreen; - uint8_t rgbRed; - }; - - // Determines the size of the BMP info header. Returns true if the size is - // valid. - bool getInfoHeaderSize(SharedBuffer* data); - - // Processes the BMP info header. Returns true if the info header could be - // decoded. - bool processInfoHeader(SharedBuffer* data); - - // Helper function for processInfoHeader() which does the actual reading of - // header values from the byte stream. Returns false on error. - bool readInfoHeader(SharedBuffer* data); - - // Returns true if this is a Windows V4+ BMP. - inline bool isWindowsV4Plus() const - { - // Windows V4 info header is 108 bytes. V5 is 124 bytes. - return (m_infoHeader.biSize == 108) || (m_infoHeader.biSize == 124); - } - - // Returns false if consistency errors are found in the info header. - bool isInfoHeaderValid() const; - - // For BI_BITFIELDS images, initializes the m_bitMasks[] and m_bitOffsets[] - // arrays. processInfoHeader() will initialize these for other compression - // types where needed. - bool processBitmasks(SharedBuffer* data); - - // For paletted images, allocates and initializes the m_colorTable[] array. - bool processColorTable(SharedBuffer* data); - - // Processes an RLE-encoded image. Returns true if the entire image was - // decoded. - bool processRLEData(SharedBuffer* data); - - // Processes a set of non-RLE-compressed pixels. Two cases: - // * inRLE = true: the data is inside an RLE-encoded bitmap. Tries to - // process |numPixels| pixels on the current row; returns true on - // success. - // * inRLE = false: the data is inside a non-RLE-encoded bitmap. - // |numPixels| is ignored. Expects |m_coord| to point at the beginning - // of the next row to be decoded. Tries to process as many complete - // rows as possible. Returns true if the whole image was decoded. - bool processNonRLEData(SharedBuffer* data, bool inRLE, int numPixels); - - // Returns true if the current y-coordinate plus |numRows| would be past - // the end of the image. Here "plus" means "toward the end of the image", - // so downwards for m_isTopDown images and upwards otherwise. - inline bool pastEndOfImage(int numRows) - { - return m_isTopDown - ? ((m_coord.y() + numRows) >= size().height()) - : ((m_coord.y() - numRows) < 0); - } - - // Returns the pixel data for the current X coordinate in a uint32_t. - // Assumes m_decodedOffset has been set to the beginning of the current - // row. - // NOTE: Only as many bytes of the return value as are needed to hold the - // pixel data will actually be set. - inline uint32_t readCurrentPixel(SharedBuffer* data, int bytesPerPixel) const - { - const int additionalOffset = m_coord.x() * bytesPerPixel; - switch (bytesPerPixel) { - case 2: - return readUint16(data, additionalOffset); - - case 3: { - // It doesn't matter that we never set the most significant byte of - // the return value here in little-endian mode, the caller won't - // read it. - uint32_t pixel; - memcpy(&pixel, - &data->data()[m_decodedOffset + additionalOffset], 3); - #if PLATFORM(BIG_ENDIAN) - pixel = ((pixel & 0xff00) << 8) | ((pixel & 0xff0000) >> 8) | - ((pixel & 0xff000000) >> 24); - #endif - return pixel; - } - - case 4: - return readUint32(data, additionalOffset); - - default: - ASSERT_NOT_REACHED(); - return 0; - } - } - - // Returns the value of the desired component (0, 1, 2, 3 == R, G, B, A) in - // the given pixel data. - inline unsigned getComponent(uint32_t pixel, int component) const - { - return ((pixel & m_bitMasks[component]) >> m_bitShiftsRight[component]) - << m_bitShiftsLeft[component]; - } - - inline unsigned getAlpha(uint32_t pixel) const - { - // For images without alpha, return alpha of 0xff. - if (m_bitMasks[3] == 0) - return 0xff; - - return getComponent(pixel, 3); - } - - // Sets the current pixel to the color given by |colorIndex|. This also - // increments the relevant local variables to move the current pixel right - // by one. - inline void setI(size_t colorIndex) - { - setRGBA(m_colorTable[colorIndex].rgbRed, m_colorTable[colorIndex].rgbGreen, - m_colorTable[colorIndex].rgbBlue, 0xff); - } - - // Like setI(), but with the individual component values specified. - inline void setRGBA(unsigned red, unsigned green, unsigned blue, unsigned alpha) - { - RGBA32Buffer::setRGBA( - m_frameBufferCache.first().bitmap().getAddr32(m_coord.x(), m_coord.y()), - red, green, blue, alpha); - m_coord.move(1, 0); - } - - // Fills pixels from the current X-coordinate up to, but not including, - // |endCoord| with the color given by the individual components. This also - // increments the relevant local variables to move the current pixel right - // to |endCoord|. - inline void fillRGBA(int endCoord, unsigned red, unsigned green, unsigned blue, unsigned alpha) - { - while (m_coord.x() < endCoord) - setRGBA(red, green, blue, alpha); - } - - // Resets the relevant local variables to start drawing at the left edge of - // the "next" row, where "next" is above or below the current row depending - // on the value of |m_isTopDown|. - void moveBufferToNextRow(); - - // The BMP info header. - BitmapInfoHeader m_infoHeader; - - // True if this is an OS/2 1.x (aka Windows 2.x) BMP. The struct layouts - // for this type of BMP are slightly different from the later, more common - // formats. - bool m_isOS21x; - - // True if this is an OS/2 2.x BMP. The meanings of compression types 3 - // and 4 for this type of BMP differ from Windows V3+ BMPs. - // - // This will be falsely negative in some cases, but only ones where the way - // we misinterpret the data is irrelevant. - bool m_isOS22x; - - // True if the BMP is not vertically flipped, that is, the first line of - // raster data in the file is the top line of the image. - bool m_isTopDown; - - // These flags get set to false as we finish each processing stage. - bool m_needToProcessBitmasks; - bool m_needToProcessColorTable; - - // Masks/offsets for the color values for non-palette formats. These are - // bitwise, with array entries 0, 1, 2, 3 corresponding to R, G, B, A. - // - // The right/left shift values are meant to be applied after the masks. - // We need to right shift to compensate for the bitfields' offsets into the - // 32 bits of pixel data, and left shift to scale the color values up for - // fields with less than 8 bits of precision. Sadly, we can't just combine - // these into one shift value because the net shift amount could go either - // direction. (If only "<< -x" were equivalent to ">> x"...) - uint32_t m_bitMasks[4]; - int m_bitShiftsRight[4]; - int m_bitShiftsLeft[4]; - - // The color palette, for paletted formats. - size_t m_tableSizeInBytes; - Vector<RGBTriple> m_colorTable; - - // The coordinate to which we've decoded the image. - IntPoint m_coord; - - // Variables that track whether we've seen pixels with alpha values != 0 - // and == 0, respectively. See comments in processNonRLEData() on how - // these are used. - bool m_seenNonZeroAlphaPixel; - bool m_seenZeroAlphaPixel; - }; - -} // namespace WebCore - -#endif |