FFmpeg
tiff_common.h
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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,
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 */
int ff_tadd_string_metadata(int count, const char *name, GetByteContext *gb, int le, AVDictionary **metadata)
Adds a string of count characters into the metadata dictionary.
Definition: tiff_common.c:241
int ff_tread_tag(GetByteContext *gb, int le, unsigned *tag, unsigned *type, unsigned *count, int *next)
Reads the first 3 fields of a TIFF tag, which are the tag id, the tag type and the count of values fo...
Definition: tiff_common.c:286
TIFF constants & data structures.
GLint GLenum type
Definition: opengl_enc.c:104
int ff_tis_ifd(unsigned tag)
Returns a value > 0 if the tag is a known IFD-tag.
Definition: tiff_common.c:31
static const uint8_t type_sizes[14]
sizes of various TIFF field types (string size = 100)
Definition: tiff_common.h:54
uint8_t
unsigned ff_tget_short(GetByteContext *gb, int le)
Reads a short from the bytestream using given endianness.
Definition: tiff_common.c:43
int ff_tadd_rational_metadata(int count, const char *name, const char *sep, GetByteContext *gb, int le, AVDictionary **metadata)
Adds count rationals converted to a string into the metadata dictionary.
Definition: tiff_common.c:82
unsigned ff_tget_long(GetByteContext *gb, int le)
Reads a long from the bytestream using given endianness.
Definition: tiff_common.c:49
uint32_t tag
Definition: movenc.c:1600
unsigned ff_tget(GetByteContext *gb, int type, int le)
Reads a byte from the bytestream using given endianness.
Definition: tiff_common.c:62
GLsizei count
Definition: opengl_enc.c:108
int ff_tdecode_header(GetByteContext *gb, int *le, int *ifd_offset)
Decodes a TIFF header from the input bytestream and sets the endianness in *le and the offset to the ...
Definition: tiff_common.c:261
TiffTypes
data type identifiers for TIFF tags
Definition: tiff_common.h:37
static const uint16_t ifd_tags[]
Definition: tiff_common.h:58
Libavcodec external API header.
int ff_tadd_doubles_metadata(int count, const char *name, const char *sep, GetByteContext *gb, int le, AVDictionary **metadata)
Adds count doubles converted to a string into the metadata dictionary.
Definition: tiff_common.c:147
int ff_tadd_bytes_metadata(int count, const char *name, const char *sep, GetByteContext *gb, int le, int is_signed, AVDictionary **metadata)
Adds count bytes converted to a string into the metadata dictionary.
Definition: tiff_common.c:210
double ff_tget_double(GetByteContext *gb, int le)
Reads a double from the bytestream using given endianness.
Definition: tiff_common.c:55
int ff_tadd_long_metadata(int count, const char *name, const char *sep, GetByteContext *gb, int le, AVDictionary **metadata)
Adds count longs converted to a string into the metadata dictionary.
Definition: tiff_common.c:116
int ff_tadd_shorts_metadata(int count, const char *name, const char *sep, GetByteContext *gb, int le, int is_signed, AVDictionary **metadata)
Adds count shorts converted to a string into the metadata dictionary.
Definition: tiff_common.c:178
const char * name
Definition: opengl_enc.c:102