ffmpeg/libavcodec/mpeg4audio.h

110 lines
5.8 KiB
C
Raw Normal View History

/*
* MPEG-4 Audio common header
* Copyright (c) 2008 Baptiste Coudurier <baptiste.coudurier@free.fr>
*
* 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 AVCODEC_MPEG4AUDIO_H
#define AVCODEC_MPEG4AUDIO_H
#include <stdint.h>
#include "get_bits.h"
#include "put_bits.h"
typedef struct MPEG4AudioConfig {
int object_type;
int sampling_index;
int sample_rate;
int chan_config;
int sbr; ///< -1 implicit, 1 presence
int ext_object_type;
int ext_sampling_index;
int ext_sample_rate;
int ext_chan_config;
int channels;
int ps; ///< -1 implicit, 1 presence
} MPEG4AudioConfig;
Add support for building shared libraries with MSVC This requires the makedef perl script by Derek, from the c89-to-c99 repo. That scripts produces a .def file, listing the symbols to be exported, based on the gcc version scripts and the built object files. To properly load non-function symbols from DLL files, the data symbol declarations need to have the attribute __declspec(dllimport) when building the calling code. (On mingw, the linker can fix this up automatically, which is why it has not been an issue so far. If this attribute is omitted, linking actually succeeds, but reads from the table will not produce the desired results at runtime.) MSVC seems to manage to link DLLs (and run properly) even if this attribute is present while building the library itself (which normally isn't recommended) - other object files in the same library manage to link to the symbol (with a small warning at link time, like "warning LNK4049: locally defined symbol _avpriv_mpa_bitrate_tab imported" - it doesn't seem to be possible to squelch this warning), and the definition of the tables themselves produce a warning that can be squelched ("warning C4273: 'avpriv_mpa_bitrate_tab' : inconsistent dll linkage, see previous definition of 'avpriv_mpa_bitrate_tab'). In this setup, mingw isn't able to link object files that refer to data symbols with __declspec(dllimport) without those symbols actually being linked via a DLL (linking avcodec.dll ends up with errors like "undefined reference to `__imp__avpriv_mpa_freq_tab'"). The dllimport declspec isn't needed at all in mingw, so we simply choose not to declare it for other compilers than MSVC that requires it. (If ICL support later requires it, the condition can be extended later to include both of them.) This also implies that code that is built to link to a certain library as a DLL can't link to the same library as a static library. Therefore, we only allow building either static or shared but not both at the same time. (That is, static libraries as such can be, and actually are, built - this is used for linking the test tools to internal symbols in the libraries - but e.g. libavformat built to link to libavcodec as a DLL cannot link statically to libavcodec.) Also, linking to DLLs is slightly different from linking to shared libraries on other platforms. DLLs use a thing called import libraries, which is basically a stub library allowing the linker to know which symbols exist in the DLL and what name the DLL will have at runtime. In mingw/gcc, the import library is usually named libfoo.dll.a, which goes next to a static library named libfoo.a. This allows gcc to pick the dynamic one, if available, from the normal -lfoo switches, just as it does for libfoo.a vs libfoo.so on Unix. On MSVC however, you need to literally specify the name of the import library instead of the static library. Signed-off-by: Martin Storsjö <martin@martin.st>
2012-10-18 10:53:19 +02:00
extern av_export const int avpriv_mpeg4audio_sample_rates[16];
extern const uint8_t ff_mpeg4audio_channels[8];
/**
* Parse MPEG-4 systems extradata to retrieve audio configuration.
* @param[in] c MPEG4AudioConfig structure to fill.
* @param[in] buf Extradata from container.
* @param[in] bit_size Extradata size in bits.
* @param[in] sync_extension look for a sync extension after config if true.
* @return On error -1 is returned, on success AudioSpecificConfig bit index in extradata.
*/
int avpriv_mpeg4audio_get_config(MPEG4AudioConfig *c, const uint8_t *buf,
int bit_size, int sync_extension);
enum AudioObjectType {
AOT_NULL,
// Support? Name
AOT_AAC_MAIN, ///< Y Main
AOT_AAC_LC, ///< Y Low Complexity
AOT_AAC_SSR, ///< N (code in SoC repo) Scalable Sample Rate
AOT_AAC_LTP, ///< Y Long Term Prediction
AOT_SBR, ///< Y Spectral Band Replication
AOT_AAC_SCALABLE, ///< N Scalable
AOT_TWINVQ, ///< N Twin Vector Quantizer
AOT_CELP, ///< N Code Excited Linear Prediction
AOT_HVXC, ///< N Harmonic Vector eXcitation Coding
AOT_TTSI = 12, ///< N Text-To-Speech Interface
AOT_MAINSYNTH, ///< N Main Synthesis
AOT_WAVESYNTH, ///< N Wavetable Synthesis
AOT_MIDI, ///< N General MIDI
AOT_SAFX, ///< N Algorithmic Synthesis and Audio Effects
AOT_ER_AAC_LC, ///< N Error Resilient Low Complexity
AOT_ER_AAC_LTP = 19, ///< N Error Resilient Long Term Prediction
AOT_ER_AAC_SCALABLE, ///< N Error Resilient Scalable
AOT_ER_TWINVQ, ///< N Error Resilient Twin Vector Quantizer
AOT_ER_BSAC, ///< N Error Resilient Bit-Sliced Arithmetic Coding
AOT_ER_AAC_LD, ///< N Error Resilient Low Delay
AOT_ER_CELP, ///< N Error Resilient Code Excited Linear Prediction
AOT_ER_HVXC, ///< N Error Resilient Harmonic Vector eXcitation Coding
AOT_ER_HILN, ///< N Error Resilient Harmonic and Individual Lines plus Noise
AOT_ER_PARAM, ///< N Error Resilient Parametric
AOT_SSC, ///< N SinuSoidal Coding
AOT_PS, ///< N Parametric Stereo
AOT_SURROUND, ///< N MPEG Surround
AOT_ESCAPE, ///< Y Escape Value
AOT_L1, ///< Y Layer 1
AOT_L2, ///< Y Layer 2
AOT_L3, ///< Y Layer 3
AOT_DST, ///< N Direct Stream Transfer
AOT_ALS, ///< Y Audio LosslesS
AOT_SLS, ///< N Scalable LosslesS
AOT_SLS_NON_CORE, ///< N Scalable LosslesS (non core)
AOT_ER_AAC_ELD, ///< N Error Resilient Enhanced Low Delay
AOT_SMR_SIMPLE, ///< N Symbolic Music Representation Simple
AOT_SMR_MAIN, ///< N Symbolic Music Representation Main
AOT_USAC_NOSBR, ///< N Unified Speech and Audio Coding (no SBR)
AOT_SAOC, ///< N Spatial Audio Object Coding
AOT_LD_SURROUND, ///< N Low Delay MPEG Surround
AOT_USAC, ///< N Unified Speech and Audio Coding
};
#define MAX_PCE_SIZE 304 ///<Maximum size of a PCE including the 3-bit ID_PCE
///<marker and the comment
int avpriv_copy_pce_data(PutBitContext *pb, GetBitContext *gb);
#endif /* AVCODEC_MPEG4AUDIO_H */