gecko-dev/image/BMPFileHeaders.h

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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_image_BMPFileHeaders_h
#define mozilla_image_BMPFileHeaders_h
#include <stddef.h>
#include <stdint.h>
namespace mozilla {
namespace image {
// This is the real BIH size (as contained in the bihsize field of
// BMPFILEHEADER).
struct BIH_LENGTH {
enum {
OS2 = 12,
WIN_V3 = 40,
WIN_V5 = 124
};
};
struct BIH_INTERNAL_LENGTH {
enum {
OS2 = 8,
WIN_V3 = 36,
WIN_V5 = 120
};
};
struct BMPFILEHEADER {
char signature[2]; // String "BM"
uint32_t filesize;
int32_t reserved; // Zero
uint32_t dataoffset; // Offset to raster data
uint32_t bihsize;
// The length of the bitmap file header as defined in the BMP spec.
static const size_t LENGTH = 14;
// Internally we store the bitmap file header with an additional 4 bytes which
// is used to store the bitmap information header size.
static const size_t INTERNAL_LENGTH = 18;
};
struct BMP_HEADER_LENGTH {
enum {
OS2 = BMPFILEHEADER::INTERNAL_LENGTH + BIH_INTERNAL_LENGTH::OS2,
WIN_V3 = BMPFILEHEADER::INTERNAL_LENGTH + BIH_INTERNAL_LENGTH::WIN_V3,
WIN_V5 = BMPFILEHEADER::INTERNAL_LENGTH + BIH_INTERNAL_LENGTH::WIN_V5
};
};
struct xyz {
int32_t x, y, z;
};
struct xyzTriple {
xyz r, g, b;
};
struct BITMAPV5HEADER {
int32_t width; // Uint16 in OS/2 BMPs
int32_t height; // Uint16 in OS/2 BMPs
uint16_t planes; // =1
uint16_t bpp; // Bits per pixel.
// The rest of the header is not available in OS/2 BMP Files
uint32_t compression; // 0=no compression 1=8bit RLE 2=4bit RLE
uint32_t image_size; // (compressed) image size. Can be 0 if
// compression==0
uint32_t xppm; // Pixels per meter, horizontal
uint32_t yppm; // Pixels per meter, vertical
uint32_t colors; // Used Colors
uint32_t important_colors; // Number of important colors. 0=all
uint32_t red_mask; // Bits used for red component
uint32_t green_mask; // Bits used for green component
uint32_t blue_mask; // Bits used for blue component
uint32_t alpha_mask; // Bits used for alpha component
uint32_t color_space; // 0x73524742=LCS_sRGB ...
// These members are unused unless color_space == LCS_CALIBRATED_RGB
xyzTriple white_point; // Logical white point
uint32_t gamma_red; // Red gamma component
uint32_t gamma_green; // Green gamma component
uint32_t gamma_blue; // Blue gamma component
uint32_t intent; // Rendering intent
// These members are unused unless color_space == LCS_PROFILE_*
uint32_t profile_offset; // Offset to profile data in bytes
uint32_t profile_size; // Size of profile data in bytes
uint32_t reserved; // =0
static const uint32_t COLOR_SPACE_LCS_SRGB = 0x73524742;
};
struct colorTable {
uint8_t red;
uint8_t green;
uint8_t blue;
};
struct bitFields {
uint32_t red;
uint32_t green;
uint32_t blue;
uint8_t redLeftShift;
uint8_t redRightShift;
uint8_t greenLeftShift;
uint8_t greenRightShift;
uint8_t blueLeftShift;
uint8_t blueRightShift;
// Length of the bitfields structure in the BMP file.
static const size_t LENGTH = 12;
};
struct BMPINFOHEADER {
// BMPINFOHEADER.compression definitions.
enum {
RGB = 0,
RLE8 = 1,
RLE4 = 2,
BITFIELDS = 3,
// ALPHABITFIELDS means no compression and specifies alpha bits. Valid only
// for 32bpp and 16bpp.
ALPHABITFIELDS = 4
};
};
// RLE escape codes.
struct RLE {
enum {
ESCAPE = 0,
ESCAPE_EOL = 0,
ESCAPE_EOF = 1,
ESCAPE_DELTA = 2
};
};
/// enums for mState
enum ERLEState {
eRLEStateInitial,
eRLEStateNeedSecondEscapeByte,
eRLEStateNeedXDelta,
eRLEStateNeedYDelta, ///< mStateData will hold x delta
eRLEStateAbsoluteMode, ///< mStateData will hold count of existing data
///< to read
eRLEStateAbsoluteModePadded ///< As above, but another byte of data has to
///< be read as padding
};
} // namespace image
} // namespace mozilla
#endif // mozilla_image_BMPFileHeaders_h