ffmpeg/libavcodec/tiff_common.h

   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 */