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Diffstat (limited to 'leptonica/src/bmp.h')
| -rw-r--r-- | leptonica/src/bmp.h | 124 |
1 files changed, 124 insertions, 0 deletions
diff --git a/leptonica/src/bmp.h b/leptonica/src/bmp.h new file mode 100644 index 00000000..568c9901 --- /dev/null +++ b/leptonica/src/bmp.h @@ -0,0 +1,124 @@ +/*====================================================================* + - Copyright (C) 2001 Leptonica. All rights reserved. + - + - Redistribution and use in source and binary forms, with or without + - modification, are permitted provided that the following conditions + - are met: + - 1. Redistributions of source code must retain the above copyright + - notice, this list of conditions and the following disclaimer. + - 2. 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. + - + - 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 ANY + - 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 LEPTONICA_BMP_H +#define LEPTONICA_BMP_H + +/*! + * \file bmp.h + * + * <pre> + * This file is here to describe the fields in the header of + * the BMP file. These fields are not used directly in Leptonica. + * The only thing we use are the sizes of these two headers. + * Furthermore, because of potential namespace conflicts with + * the typedefs and defined sizes, we have changed the names + * to protect anyone who may also need to use the original definitions. + * Thanks to J. D. Bryan for pointing out the potential problems when + * developing on Win32 compatible systems. + * </pre> + */ + +/*-------------------------------------------------------------* + * BMP file header * + *-------------------------------------------------------------*/ + +/*! BMP file header + * + * Notes: + * (1) The bfSize field is stored as a 32 bit integer and includes + * the size of the BMP_FileHeader, BMP_InfoHeader, the color + * table (if any), and the size of the DIB bits. + * (2) The bfOffBits field is also stored as a 32 bit integer and + * contains the absolute offset in bytes of the image data + * in this file. Some bmp files have additional data after the + * BMP_InfoHeader and before the color table (if it exists). + * However, enabling reading of these files makes the reader + * vulnerable to various malware attacks. Therefore we do not + * read bmp files with extra data, and require that the size + * of the color table in bytes is + * offset - sizeof(BMP_FileHeader) - sizeof(BMP_InfoHeader) + * (3) Use arrays of l_uint8[] to make an endianness agnostic + * access to the BMP_FileHeader easier. + */ +struct BMP_FileHeader +{ + l_uint8 bfType[2]; /*!< file type; must be "BM" */ + l_uint8 bfSize[4]; /*!< length of the file; + sizeof(BMP_FileHeader) + + sizeof(BMP_InfoHeader) + + size of optional extra data + + size of color table + + size of DIB bits */ + l_uint8 bfReserved1[2]; /*!< don't care (set to 0) */ + l_uint8 bfReserved2[2]; /*!< don't care (set to 0) */ + l_uint8 bfOffBits[4]; /*!< offset from beginning of file */ +}; +typedef struct BMP_FileHeader BMP_FH; + +/*! Number of bytes in a BMP file header */ +#define BMP_FHBYTES sizeof(BMP_FH) + + +/*-------------------------------------------------------------* + * BMP info header * + *-------------------------------------------------------------*/ + +/*! BMP info header */ +struct BMP_InfoHeader +{ + l_int32 biSize; /*!< size of the BMP_InfoHeader struct */ + l_int32 biWidth; /*!< bitmap width in pixels */ + l_int32 biHeight; /*!< bitmap height in pixels */ + l_int16 biPlanes; /*!< number of bitmap planes */ + l_int16 biBitCount; /*!< number of bits per pixel */ + l_int32 biCompression; /*!< compress format (0 == uncompressed) */ + l_int32 biSizeImage; /*!< size of image in bytes */ + l_int32 biXPelsPerMeter; /*!< pixels per meter in x direction */ + l_int32 biYPelsPerMeter; /*!< pixels per meter in y direction */ + l_int32 biClrUsed; /*!< number of colors used */ + l_int32 biClrImportant; /*!< number of important colors used */ +}; +typedef struct BMP_InfoHeader BMP_IH; + +/*! Number of bytes in a BMP info header */ +#define BMP_IHBYTES sizeof(BMP_IH) + + +/*-------------------------------------------------------------* + * Align BMP headers on 4 byte boundaries * + *-------------------------------------------------------------*/ + +/*! BMP_IH is misaligned, causing crashes on some big-endians. + * A packed struct forces alignment. */ +#if defined(__GNUC__) +typedef struct __attribute__((__packed__)) { + BMP_FH bmpfh; + BMP_IH bmpih; +} BMP_HEADER; +#endif + +#endif /* LEPTONICA_BMP_H */ |