ffmpeg/libavcodec/tiff_common.h

132 lines
4.3 KiB
C

/*
* TIFF Common Routines
* Copyright (c) 2013 Thilo Borgmann <thilo.borgmann _at_ mail.de>
*
* This file is part of FFmpeg.
*
* FFmpeg is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* FFmpeg is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with FFmpeg; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*/
/**
* @file
* TIFF Common Routines
* @author Thilo Borgmann <thilo.borgmann _at_ mail.de>
*/
#ifndef AVCODEC_TIFF_COMMON_H
#define AVCODEC_TIFF_COMMON_H
#include <stdint.h>
#include "libavutil/dict.h"
#include "bytestream.h"
/** data type identifiers for TIFF tags */
enum TiffTypes {
TIFF_BYTE = 1,
TIFF_STRING,
TIFF_SHORT,
TIFF_LONG,
TIFF_RATIONAL,
TIFF_SBYTE,
TIFF_UNDEFINED,
TIFF_SSHORT,
TIFF_SLONG,
TIFF_SRATIONAL,
TIFF_FLOAT,
TIFF_DOUBLE,
TIFF_IFD
};
/** sizes of various TIFF field types (string size = 100)*/
static const uint8_t type_sizes[14] = {
0, 1, 100, 2, 4, 8, 1, 1, 2, 4, 8, 4, 8, 4
};
static const uint16_t ifd_tags[] = {
0x8769, // EXIF IFD
0x8825, // GPS IFD
0xA005 // Interoperability IFD
};
/** Returns a value > 0 if the tag is a known IFD-tag.
* The return value is the array index + 1 within ifd_tags[].
*/
int ff_tis_ifd(unsigned tag);
/** Reads a short from the bytestream using given endianness. */
unsigned ff_tget_short(GetByteContext *gb, int le);
/** Reads a long from the bytestream using given endianness. */
unsigned ff_tget_long(GetByteContext *gb, int le);
/** Reads a double from the bytestream using given endianness. */
double ff_tget_double(GetByteContext *gb, int le);
/** Reads a byte from the bytestream using given endianness. */
unsigned ff_tget(GetByteContext *gb, int type, int le);
/** Adds count rationals converted to a string
* into the metadata dictionary.
*/
int ff_tadd_rational_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.
*/
int ff_tadd_long_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.
*/
int ff_tadd_doubles_metadata(int count, const char *name, const char *sep,
GetByteContext *gb, int le, AVDictionary **metadata);
/** Adds count shorts converted to a string
* into the metadata dictionary.
*/
int ff_tadd_shorts_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.
*/
int ff_tadd_bytes_metadata(int count, const char *name, const char *sep,
GetByteContext *gb, int le, int is_signed, AVDictionary **metadata);
/** Adds a string of count characters
* into the metadata dictionary.
*/
int ff_tadd_string_metadata(int count, const char *name,
GetByteContext *gb, int le, AVDictionary **metadata);
/** Decodes a TIFF header from the input bytestream
* and sets the endianness in *le and the offset to
* the first IFD in *ifd_offset accordingly.
*/
int ff_tdecode_header(GetByteContext *gb, int *le, int *ifd_offset);
/** Reads the first 3 fields of a TIFF tag, which are
* the tag id, the tag type and the count of values for that tag.
* Afterwards the bytestream is located at the first value to read and
* *next holds the bytestream offset of the following tag.
*/
int ff_tread_tag(GetByteContext *gb, int le, unsigned *tag, unsigned *type,
unsigned *count, int *next);
#endif /* AVCODEC_TIFF_COMMON_H */