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avutil.h
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/*
* copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
*
* 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
*/
#ifndef AVUTIL_AVUTIL_H
#define AVUTIL_AVUTIL_H
/**
* @file
* @ingroup lavu
* Convenience header that includes @ref lavu "libavutil"'s core.
*/
/**
* @mainpage
*
* @section ffmpeg_intro Introduction
*
* This document describes the usage of the different libraries
* provided by FFmpeg.
*
* @li @ref libavc "libavcodec" encoding/decoding library
* @li @ref lavfi "libavfilter" graph-based frame editing library
* @li @ref libavf "libavformat" I/O and muxing/demuxing library
* @li @ref lavd "libavdevice" special devices muxing/demuxing library
* @li @ref lavu "libavutil" common utility library
* @li @ref lswr "libswresample" audio resampling, format conversion and mixing
* @li @ref lpp "libpostproc" post processing library
* @li @ref libsws "libswscale" color conversion and scaling library
*
* @section ffmpeg_versioning Versioning and compatibility
*
* Each of the FFmpeg libraries contains a version.h header, which defines a
* major, minor and micro version number with the
* <em>LIBRARYNAME_VERSION_{MAJOR,MINOR,MICRO}</em> macros. The major version
* number is incremented with backward incompatible changes - e.g. removing
* parts of the public API, reordering public struct members, etc. The minor
* version number is incremented for backward compatible API changes or major
* new features - e.g. adding a new public function or a new decoder. The micro
* version number is incremented for smaller changes that a calling program
* might still want to check for - e.g. changing behavior in a previously
* unspecified situation.
*
* FFmpeg guarantees backward API and ABI compatibility for each library as long
* as its major version number is unchanged. This means that no public symbols
* will be removed or renamed. Types and names of the public struct members and
* values of public macros and enums will remain the same (unless they were
* explicitly declared as not part of the public API). Documented behavior will
* not change.
*
* In other words, any correct program that works with a given FFmpeg snapshot
* should work just as well without any changes with any later snapshot with the
* same major versions. This applies to both rebuilding the program against new
* FFmpeg versions or to replacing the dynamic FFmpeg libraries that a program
* links against.
*
* However, new public symbols may be added and new members may be appended to
* public structs whose size is not part of public ABI (most public structs in
* FFmpeg). New macros and enum values may be added. Behavior in undocumented
* situations may change slightly (and be documented). All those are accompanied
* by an entry in doc/APIchanges and incrementing either the minor or micro
* version number.
*/
/**
* @defgroup lavu libavutil
* Common code shared across all FFmpeg libraries.
*
* @note
* libavutil is designed to be modular. In most cases, in order to use the
* functions provided by one component of libavutil you must explicitly include
* the specific header containing that feature. If you are only using
* media-related components, you could simply include libavutil/avutil.h, which
* brings in most of the "core" components.
*
* @{
*
* @defgroup lavu_crypto Crypto and Hashing
*
* @{
* @}
*
* @defgroup lavu_math Mathematics
* @{
*
* @}
*
* @defgroup lavu_string String Manipulation
*
* @{
*
* @}
*
* @defgroup lavu_mem Memory Management
*
* @{
*
* @}
*
* @defgroup lavu_data Data Structures
* @{
*
* @}
*
* @defgroup lavu_video Video related
*
* @{
*
* @}
*
* @defgroup lavu_audio Audio related
*
* @{
*
* @}
*
* @defgroup lavu_error Error Codes
*
* @{
*
* @}
*
* @defgroup lavu_log Logging Facility
*
* @{
*
* @}
*
* @defgroup lavu_misc Other
*
* @{
*
* @defgroup preproc_misc Preprocessor String Macros
*
* @{
*
* @}
*
* @defgroup version_utils Library Version Macros
*
* @{
*
* @}
*/
/**
* @addtogroup lavu_ver
* @{
*/
/**
* Return the LIBAVUTIL_VERSION_INT constant.
*/
unsigned avutil_version(void);
/**
* Return an informative version string. This usually is the actual release
* version number or a git commit description. This string has no fixed format
* and can change any time. It should never be parsed by code.
*/
const char *av_version_info(void);
/**
* Return the libavutil build-time configuration.
*/
const char *avutil_configuration(void);
/**
* Return the libavutil license.
*/
const char *avutil_license(void);
/**
* @}
*/
/**
* @addtogroup lavu_media Media Type
* @brief Media Type
*/
enum AVMediaType {
AVMEDIA_TYPE_UNKNOWN = -1, ///< Usually treated as AVMEDIA_TYPE_DATA
AVMEDIA_TYPE_VIDEO,
AVMEDIA_TYPE_AUDIO,
AVMEDIA_TYPE_DATA, ///< Opaque data information usually continuous
AVMEDIA_TYPE_SUBTITLE,
AVMEDIA_TYPE_ATTACHMENT, ///< Opaque data information usually sparse
AVMEDIA_TYPE_NB
};
/**
* Return a string describing the media_type enum, NULL if media_type
* is unknown.
*/
const char *av_get_media_type_string(enum AVMediaType media_type);
/**
* @defgroup lavu_const Constants
* @{
*
* @defgroup lavu_enc Encoding specific
*
* @note those definition should move to avcodec
* @{
*/
#define FF_LAMBDA_SHIFT 7
#define FF_LAMBDA_SCALE (1<<FF_LAMBDA_SHIFT)
#define FF_QP2LAMBDA 118 ///< factor to convert from H.263 QP to lambda
#define FF_LAMBDA_MAX (256*128-1)
#define FF_QUALITY_SCALE FF_LAMBDA_SCALE //FIXME maybe remove
/**
* @}
* @defgroup lavu_time Timestamp specific
*
* FFmpeg internal timebase and timestamp definitions
*
* @{
*/
/**
* @brief Undefined timestamp value
*
* Usually reported by demuxer that work on containers that do not provide
* either pts or dts.
*/
#define AV_NOPTS_VALUE ((int64_t)UINT64_C(0x8000000000000000))
/**
* Internal time base represented as integer
*/
#define AV_TIME_BASE 1000000
/**
* Internal time base represented as fractional value
*/
#ifdef __cplusplus
/* ISO C++ forbids compound-literals. */
#define AV_TIME_BASE_Q av_make_q(1, AV_TIME_BASE)
#else
#define AV_TIME_BASE_Q (AVRational){1, AV_TIME_BASE}
#endif
/**
* @}
* @}
* @defgroup lavu_picture Image related
*
* AVPicture types, pixel formats and basic image planes manipulation.
*
* @{
*/
enum AVPictureType {
AV_PICTURE_TYPE_NONE = 0, ///< Undefined
AV_PICTURE_TYPE_I, ///< Intra
AV_PICTURE_TYPE_P, ///< Predicted
AV_PICTURE_TYPE_B, ///< Bi-dir predicted
AV_PICTURE_TYPE_S, ///< S(GMC)-VOP MPEG-4
AV_PICTURE_TYPE_SI, ///< Switching Intra
AV_PICTURE_TYPE_SP, ///< Switching Predicted
AV_PICTURE_TYPE_BI, ///< BI type
};
/**
* Return a single letter to describe the given picture type
* pict_type.
*
* @param[in] pict_type the picture type @return a single character
* representing the picture type, '?' if pict_type is unknown
*/
char av_get_picture_type_char(enum AVPictureType pict_type);
/**
* @}
*/
#include "common.h"
#include "rational.h"
#include "version.h"
#include "macros.h"
#include "mathematics.h"
#include "log.h"
#include "pixfmt.h"
/**
* Return x default pointer in case p is NULL.
*/
static inline void *av_x_if_null(const void *p, const void *x)
{
return (void *)(intptr_t)(p ? p : x);
}
/**
* Compute the length of an integer list.
*
* @param elsize size in bytes of each list element (only 1, 2, 4 or 8)
* @param term list terminator (usually 0 or -1)
* @param list pointer to the list
* @return length of the list, in elements, not counting the terminator
*/
unsigned av_int_list_length_for_size(unsigned elsize,
const void *list, uint64_t term) av_pure;
/**
* Compute the length of an integer list.
*
* @param term list terminator (usually 0 or -1)
* @param list pointer to the list
* @return length of the list, in elements, not counting the terminator
*/
#define av_int_list_length(list, term) \
av_int_list_length_for_size(sizeof(*(list)), list, term)
/**
* Return the fractional representation of the internal time base.
*/
AVRational av_get_time_base_q(void);
#define AV_FOURCC_MAX_STRING_SIZE 32
#define av_fourcc2str(fourcc) av_fourcc_make_string((char[AV_FOURCC_MAX_STRING_SIZE]){0}, fourcc)
/**
* Fill the provided buffer with a string containing a FourCC (four-character
* code) representation.
*
* @param buf a buffer with size in bytes of at least AV_FOURCC_MAX_STRING_SIZE
* @param fourcc the fourcc to represent
* @return the buffer in input
*/
char *av_fourcc_make_string(char *buf, uint32_t fourcc);
/**
* @}
* @}
*/
#endif /* AVUTIL_AVUTIL_H */
av_pure
#define av_pure
Definition attributes.h:76
common.h
common internal and external API header
av_get_media_type_string
const char * av_get_media_type_string(enum AVMediaType media_type)
Return a string describing the media_type enum, NULL if media_type is unknown.
av_int_list_length_for_size
unsigned av_int_list_length_for_size(unsigned elsize, const void *list, uint64_t term) av_pure
Compute the length of an integer list.
av_fourcc_make_string
char * av_fourcc_make_string(char *buf, uint32_t fourcc)
Fill the provided buffer with a string containing a FourCC (four-character code) representation.
AVMediaType
AVMediaType
Definition avutil.h:199
av_x_if_null
static void * av_x_if_null(const void *p, const void *x)
Return x default pointer in case p is NULL.
Definition avutil.h:312
av_get_time_base_q
AVRational av_get_time_base_q(void)
Return the fractional representation of the internal time base.
AVMEDIA_TYPE_ATTACHMENT
@ AVMEDIA_TYPE_ATTACHMENT
Opaque data information usually sparse.
Definition avutil.h:205
AVMEDIA_TYPE_AUDIO
@ AVMEDIA_TYPE_AUDIO
Definition avutil.h:202
AVMEDIA_TYPE_NB
@ AVMEDIA_TYPE_NB
Definition avutil.h:206
AVMEDIA_TYPE_SUBTITLE
@ AVMEDIA_TYPE_SUBTITLE
Definition avutil.h:204
AVMEDIA_TYPE_VIDEO
@ AVMEDIA_TYPE_VIDEO
Definition avutil.h:201
AVMEDIA_TYPE_DATA
@ AVMEDIA_TYPE_DATA
Opaque data information usually continuous.
Definition avutil.h:203
AVMEDIA_TYPE_UNKNOWN
@ AVMEDIA_TYPE_UNKNOWN
Usually treated as AVMEDIA_TYPE_DATA.
Definition avutil.h:200
av_get_picture_type_char
char av_get_picture_type_char(enum AVPictureType pict_type)
Return a single letter to describe the given picture type pict_type.
AVPictureType
AVPictureType
Definition avutil.h:277
AV_PICTURE_TYPE_I
@ AV_PICTURE_TYPE_I
Intra.
Definition avutil.h:279
AV_PICTURE_TYPE_NONE
@ AV_PICTURE_TYPE_NONE
Undefined.
Definition avutil.h:278
AV_PICTURE_TYPE_BI
@ AV_PICTURE_TYPE_BI
BI type.
Definition avutil.h:285
AV_PICTURE_TYPE_SP
@ AV_PICTURE_TYPE_SP
Switching Predicted.
Definition avutil.h:284
AV_PICTURE_TYPE_P
@ AV_PICTURE_TYPE_P
Predicted.
Definition avutil.h:280
AV_PICTURE_TYPE_SI
@ AV_PICTURE_TYPE_SI
Switching Intra.
Definition avutil.h:283
AV_PICTURE_TYPE_S
@ AV_PICTURE_TYPE_S
S(GMC)-VOP MPEG-4.
Definition avutil.h:282
AV_PICTURE_TYPE_B
@ AV_PICTURE_TYPE_B
Bi-dir predicted.
Definition avutil.h:281
av_version_info
const char * av_version_info(void)
Return an informative version string.
avutil_license
const char * avutil_license(void)
Return the libavutil license.
avutil_configuration
const char * avutil_configuration(void)
Return the libavutil build-time configuration.
avutil_version
unsigned avutil_version(void)
Return the LIBAVUTIL_VERSION_INT constant.
version.h
swscale version macros
log.h
macros.h
Utility Preprocessor macros.
mathematics.h
pixfmt.h
pixel format definitions
rational.h
Utilties for rational number calculation.
AVRational
Rational number (pair of numerator and denominator).
Definition rational.h:58