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 /** Adds count rationals converted to a string 83 * into the metadata dictionary. 84 */ 85 int ff_tadd_rational_metadata(int count, const char *name, const char *sep, 86 GetByteContext *gb, int le, AVDictionary **metadata); 87 88 /** Adds count longs converted to a string 89 * into the metadata dictionary. 90 */ 91 int ff_tadd_long_metadata(int count, const char *name, const char *sep, 92 GetByteContext *gb, int le, AVDictionary **metadata); 93 94 /** Adds count doubles converted to a string 95 * into the metadata dictionary. 96 */ 97 int ff_tadd_doubles_metadata(int count, const char *name, const char *sep, 98 GetByteContext *gb, int le, AVDictionary **metadata); 99 100 /** Adds count shorts converted to a string 101 * into the metadata dictionary. 102 */ 103 int ff_tadd_shorts_metadata(int count, const char *name, const char *sep, 104 GetByteContext *gb, int le, int is_signed, AVDictionary **metadata); 105 106 /** Adds count bytes converted to a string 107 * into the metadata dictionary. 108 */ 109 int ff_tadd_bytes_metadata(int count, const char *name, const char *sep, 110 GetByteContext *gb, int le, int is_signed, AVDictionary **metadata); 111 112 /** Adds a string of count characters 113 * into the metadata dictionary. 114 */ 115 int ff_tadd_string_metadata(int count, const char *name, 116 GetByteContext *gb, int le, AVDictionary **metadata); 117 118 /** Decodes a TIFF header from the input bytestream 119 * and sets the endianness in *le and the offset to 120 * the first IFD in *ifd_offset accordingly. 121 */ 122 int ff_tdecode_header(GetByteContext *gb, int *le, int *ifd_offset); 123 124 /** Reads the first 3 fields of a TIFF tag, which are 125 * the tag id, the tag type and the count of values for that tag. 126 * Afterwards the bytestream is located at the first value to read and 127 * *next holds the bytestream offset of the following tag. 128 */ 129 int ff_tread_tag(GetByteContext *gb, int le, unsigned *tag, unsigned *type, 130 unsigned *count, int *next); 131 132 #endif /* AVCODEC_TIFF_COMMON_H */ 133