libavutil: add utility functions to simplify allocation of audio buffers.

[libav.git] / libavutil / avutil.h

/*
 * copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at>
 *
 * This file is part of Libav.
 *
 * Libav 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.
 *
 * Libav 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 Libav; 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
 * external API header
 */

/**
 * @mainpage
 *
 * @section libav_intro Introduction
 *
 * This document describe the usage of the different libraries
 * provided by Libav.
 *
 * @li @ref libavc "libavcodec" encoding/decoding library
 * @li @subpage libavfilter graph based frame editing library
 * @li @ref libavf "libavformat" I/O and muxing/demuxing library
 * @li @ref lavu "libavutil" common utility library
 * @li @subpage libpostproc post processing library
 * @li @subpage libswscale  color conversion and scaling library
 *
 */

/**
 * @defgroup lavu Common utility functions
 *
 * @brief
 * libavutil contains the code shared across all the other Libav
 * libraries
 *
 * @note In order to use the functions provided by avutil you must include
 * the specific header.
 *
 * @{
 *
 * @defgroup lavu_crypto Crypto and Hashing
 *
 * @{
 * @}
 *
 * @defgroup lavu_math Maths
 * @{
 *
 * @}
 *
 * @defgroup lavu_string String Manipulation
 *
 * @{
 *
 * @}
 *
 * @defgroup lavu_mem Memory Management
 *
 * @{
 *
 * @}
 *
 * @defgroup lavu_data Data Structures
 * @{
 *
 * @}
 *
 * @defgroup lavu_audio Audio related
 *
 * @{
 *
 * @}
 *
 * @defgroup lavu_error Error Codes
 *
 * @{
 *
 * @}
 *
 * @defgroup lavu_misc Other
 *
 * @{
 *
 * @defgroup lavu_internal Internal
 *
 * Not exported functions, for internal usage only
 *
 * @{
 *
 * @}
 */


/**
 * @defgroup preproc_misc Preprocessor String Macros
 *
 * String manipulation macros
 *
 * @{
 */

#define AV_STRINGIFY(s)         AV_TOSTRING(s)
#define AV_TOSTRING(s) #s

#define AV_GLUE(a, b) a ## b
#define AV_JOIN(a, b) AV_GLUE(a, b)

#define AV_PRAGMA(s) _Pragma(#s)

/**
 * @}
 */

/**
 * @defgroup version_utils Library Version Macros
 *
 * Useful to check and match library version in order to maintain
 * backward compatibility.
 *
 * @{
 */

#define AV_VERSION_INT(a, b, c) (a<<16 | b<<8 | c)
#define AV_VERSION_DOT(a, b, c) a ##.## b ##.## c
#define AV_VERSION(a, b, c) AV_VERSION_DOT(a, b, c)

/**
 * @}
 *
 * @defgroup lavu_ver Version and Build diagnostics
 *
 * Macros and function useful to check at compiletime and at runtime
 * which version of libavutil is in use.
 *
 * @{
 */

#define LIBAVUTIL_VERSION_MAJOR 51
#define LIBAVUTIL_VERSION_MINOR 18
#define LIBAVUTIL_VERSION_MICRO  0

#define LIBAVUTIL_VERSION_INT   AV_VERSION_INT(LIBAVUTIL_VERSION_MAJOR, \
                                               LIBAVUTIL_VERSION_MINOR, \
                                               LIBAVUTIL_VERSION_MICRO)
#define LIBAVUTIL_VERSION       AV_VERSION(LIBAVUTIL_VERSION_MAJOR,     \
                                           LIBAVUTIL_VERSION_MINOR,     \
                                           LIBAVUTIL_VERSION_MICRO)
#define LIBAVUTIL_BUILD         LIBAVUTIL_VERSION_INT

#define LIBAVUTIL_IDENT         "Lavu" AV_STRINGIFY(LIBAVUTIL_VERSION)

/**
 * @}
 *
 * @defgroup depr_guards Deprecation guards
 * Those FF_API_* defines are not part of public API.
 * They may change, break or disappear at any time.
 *
 * They are used mostly internally to mark code that will be removed
 * on the next major version.
 *
 * @{
 */
#ifndef FF_API_GET_BITS_PER_SAMPLE_FMT
#define FF_API_GET_BITS_PER_SAMPLE_FMT (LIBAVUTIL_VERSION_MAJOR < 52)
#endif
#ifndef FF_API_FIND_OPT
#define FF_API_FIND_OPT                 (LIBAVUTIL_VERSION_MAJOR < 52)
#endif
#ifndef FF_API_AV_FIFO_PEEK
#define FF_API_AV_FIFO_PEEK             (LIBAVUTIL_VERSION_MAJOR < 52)
#endif
#ifndef FF_API_OLD_AVOPTIONS
#define FF_API_OLD_AVOPTIONS            (LIBAVUTIL_VERSION_MAJOR < 52)
#endif

/**
 * @}
 */

/**
 * @addtogroup lavu_ver
 * @{
 */

/**
 * Return the LIBAVUTIL_VERSION_INT constant.
 */
unsigned avutil_version(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
};

/**
 * @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
 *
 * Libav 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_C(0x8000000000000000)

/**
 * Internal time base represented as integer
 */

#define AV_TIME_BASE            1000000

/**
 * Internal time base represented as fractional value
 */

#define AV_TIME_BASE_Q          (AVRational){1, AV_TIME_BASE}

/**
 * @}
 * @}
 * @defgroup lavu_picture Image related
 *
 * AVPicture types, pixel formats and basic image planes manipulation.
 *
 * @{
 */

enum AVPictureType {
    AV_PICTURE_TYPE_I = 1, ///< Intra
    AV_PICTURE_TYPE_P,     ///< Predicted
    AV_PICTURE_TYPE_B,     ///< Bi-dir predicted
    AV_PICTURE_TYPE_S,     ///< S(GMC)-VOP MPEG4
    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 "error.h"

/**
 * @}
 * @}
 */

#endif /* AVUTIL_AVUTIL_H */