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AAC Encode

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17 Feb 2012CPOL3 min read 66.7K   5K   27  
Raw Audio data is encoded to AAC compression using ffmmpeg library.
/*
 * 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
 * external API header
 */


#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)

#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)

#define LIBAVUTIL_VERSION_MAJOR 51
#define LIBAVUTIL_VERSION_MINOR 26
#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)

/**
 * Those FF_API_* defines are not part of public API.
 * They may change, break or disappear at any time.
 */
#ifndef FF_API_OLD_EVAL_NAMES
#define FF_API_OLD_EVAL_NAMES (LIBAVUTIL_VERSION_MAJOR < 52)
#endif
#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

/**
 * 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);

enum AVMediaType {
    AVMEDIA_TYPE_UNKNOWN = -1,
    AVMEDIA_TYPE_VIDEO,
    AVMEDIA_TYPE_AUDIO,
    AVMEDIA_TYPE_DATA,
    AVMEDIA_TYPE_SUBTITLE,
    AVMEDIA_TYPE_ATTACHMENT,
    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);

#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

#define AV_NOPTS_VALUE          INT64_C(0x8000000000000000)
#define AV_TIME_BASE            1000000
#define AV_TIME_BASE_Q          (AVRational){1, AV_TIME_BASE}

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 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);

/**
 * Return x default pointer in case p is NULL.
 */
static inline const void *av_x_if_null(const void *p, const void *x)
{
    return p ? p : x;
}

#include "common.h"
#include "error.h"
#include "mathematics.h"
#include "rational.h"
#include "intfloat_readwrite.h"
#include "log.h"
#include "pixfmt.h"

#endif /* AVUTIL_AVUTIL_H */

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License

This article, along with any associated source code and files, is licensed under The Code Project Open License (CPOL)


Written By
Software Developer (Senior) 3k Techonologies
United States United States
Suresh Potluri has worked in Windows device drivers, Solid experience in NDIS Layer, developed many NDIS Miniport drivers. Extensive experience in developing NDIS miniport drivers, building WHQL/DTM setup, clearing all WHQL/DTM tests, and subsequently getting device signature/logo process for the developed drivers. He also was also solely responsible for debugging traps and blue screens for a number of years.
he also worked on many PCI based boards, developed Board support packages, Vx-Works firmware for Power PC, firmware for ARM based boards for Wireless LAN devices.

he is interested in Embedded, NDIS, MPEG.

Previously worked in Tandberg TV, Sunnyvale, Chlesio Communications, Sunnyvale, Hellosoft, Hyderabad.

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