1 /* 2 * TIFF Common Routines 3 * Copyright (c) 2013 Thilo Borgmann <thilo.borgmann _at_ mail.de> 4 * 5 * This file is part of FFmpeg. 6 * 7 * FFmpeg is free software; you can redistribute it and/or 8 * modify it under the terms of the GNU Lesser General Public 9 * License as published by the Free Software Foundation; either 10 * version 2.1 of the License, or (at your option) any later version. 11 * 12 * FFmpeg is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 15 * Lesser General Public License for more details. 16 * 17 * You should have received a copy of the GNU Lesser General Public 18 * License along with FFmpeg; if not, write to the Free Software 19 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA 20 */ 21 22 /** 23 * @file 24 * TIFF Common Routines 25 * @author Thilo Borgmann <thilo.borgmann _at_ mail.de> 26 */ 27 28 #ifndef AVCODEC_TIFF_COMMON_H 29 #define AVCODEC_TIFF_COMMON_H 30 31 #include "avcodec.h" 32 #include "tiff.h" 33 #include "bytestream.h" 34 #include "libavutil/bprint.h" 35 36 /** data type identifiers for TIFF tags */ 37 enum TiffTypes { 38 TIFF_BYTE = 1, 39 TIFF_STRING, 40 TIFF_SHORT, 41 TIFF_LONG, 42 TIFF_RATIONAL, 43 TIFF_SBYTE, 44 TIFF_UNDEFINED, 45 TIFF_SSHORT, 46 TIFF_SLONG, 47 TIFF_SRATIONAL, 48 TIFF_FLOAT, 49 TIFF_DOUBLE, 50 TIFF_IFD 51 }; 52 53 /** sizes of various TIFF field types (string size = 100)*/ 54 static const uint8_t type_sizes[14] = { 55 0, 1, 100, 2, 4, 8, 1, 1, 2, 4, 8, 4, 8, 4 56 }; 57 58 static const uint16_t ifd_tags[] = { 59 0x8769, // EXIF IFD 60 0x8825, // GPS IFD 61 0xA005 // Interoperability IFD 62 }; 63 64 65 /** Returns a value > 0 if the tag is a known IFD-tag. 66 * The return value is the array index + 1 within ifd_tags[]. 67 */ 68 int ff_tis_ifd(unsigned tag); 69 70 /** Reads a short from the bytestream using given endianness. */ 71 unsigned ff_tget_short(GetByteContext *gb, int le); 72 73 /** Reads a long from the bytestream using given endianness. */ 74 unsigned ff_tget_long(GetByteContext *gb, int le); 75 76 /** Reads a double from the bytestream using given endianness. */ 77 double ff_tget_double(GetByteContext *gb, int le); 78 79 /** Reads a byte from the bytestream using given endianness. */ 80 unsigned ff_tget(GetByteContext *gb, int type, int le); 81 82 /** Returns an allocated string containing count 83 * rational values using the given separator. 84 */ 85 char *ff_trationals2str(int *rp, int count, const char *sep); 86 87 /** Returns an allocated string containing count 88 * long values using the given separator. 89 */ 90 char *ff_tlongs2str(int32_t *lp, int count, const char *sep); 91 92 /** Returns an allocated string containing count 93 * double values using the given separator. 94 */ 95 char *ff_tdoubles2str(double *dp, int count, const char *sep); 96 97 /** Returns an allocated string containing count 98 * short values using the given separator. 99 */ 100 char *ff_tshorts2str(int16_t *sp, int count, const char *sep); 101 102 /** Adds count rationals converted to a string 103 * into the metadata dictionary. 104 */ 105 int ff_tadd_rational_metadata(int count, const char *name, const char *sep, 106 GetByteContext *gb, int le, AVDictionary **metadata); 107 108 /** Adds count longs converted to a string 109 * into the metadata dictionary. 110 */ 111 int ff_tadd_long_metadata(int count, const char *name, const char *sep, 112 GetByteContext *gb, int le, AVDictionary **metadata); 113 114 /** Adds count doubles converted to a string 115 * into the metadata dictionary. 116 */ 117 int ff_tadd_doubles_metadata(int count, const char *name, const char *sep, 118 GetByteContext *gb, int le, AVDictionary **metadata); 119 120 /** Adds count shorts converted to a string 121 * into the metadata dictionary. 122 */ 123 int ff_tadd_shorts_metadata(int count, const char *name, const char *sep, 124 GetByteContext *gb, int le, int is_signed, AVDictionary **metadata); 125 126 /** Adds count bytes converted to a string 127 * into the metadata dictionary. 128 */ 129 int ff_tadd_bytes_metadata(int count, const char *name, const char *sep, 130 GetByteContext *gb, int le, int is_signed, AVDictionary **metadata); 131 132 /** Adds a string of count characters 133 * into the metadata dictionary. 134 */ 135 int ff_tadd_string_metadata(int count, const char *name, 136 GetByteContext *gb, int le, AVDictionary **metadata); 137 138 /** Decodes a TIFF header from the input bytestream 139 * and sets the endianness in *le and the offset to 140 * the first IFD in *ifd_offset accordingly. 141 */ 142 int ff_tdecode_header(GetByteContext *gb, int *le, int *ifd_offset); 143 144 /** Reads the first 3 fields of a TIFF tag, which are 145 * the tag id, the tag type and the count of values for that tag. 146 * Afterwards the bytestream is located at the first value to read and 147 * *next holds the bytestream offset of the following tag. 148 */ 149 int ff_tread_tag(GetByteContext *gb, int le, unsigned *tag, unsigned *type, 150 unsigned *count, int *next); 151 152 #endif /* AVCODEC_TIFF_COMMON_H */ 153