mirror of
https://github.com/mstorsjo/fdk-aac.git
synced 2025-02-19 04:30:34 +01:00
4f0d97057c
- Update disclaimer in all source files. - Increment library version in each FDK sub-module. Bug 9428126 Change-Id: I490b96d4ee472246b01483202b0bb4f1e9c2a5d7
298 lines
12 KiB
C++
298 lines
12 KiB
C++
|
||
/* -----------------------------------------------------------------------------------------------------------
|
||
Software License for The Fraunhofer FDK AAC Codec Library for Android
|
||
|
||
© Copyright 1995 - 2013 Fraunhofer-Gesellschaft zur Förderung der angewandten Forschung e.V.
|
||
All rights reserved.
|
||
|
||
1. INTRODUCTION
|
||
The Fraunhofer FDK AAC Codec Library for Android ("FDK AAC Codec") is software that implements
|
||
the MPEG Advanced Audio Coding ("AAC") encoding and decoding scheme for digital audio.
|
||
This FDK AAC Codec software is intended to be used on a wide variety of Android devices.
|
||
|
||
AAC's HE-AAC and HE-AAC v2 versions are regarded as today's most efficient general perceptual
|
||
audio codecs. AAC-ELD is considered the best-performing full-bandwidth communications codec by
|
||
independent studies and is widely deployed. AAC has been standardized by ISO and IEC as part
|
||
of the MPEG specifications.
|
||
|
||
Patent licenses for necessary patent claims for the FDK AAC Codec (including those of Fraunhofer)
|
||
may be obtained through Via Licensing (www.vialicensing.com) or through the respective patent owners
|
||
individually for the purpose of encoding or decoding bit streams in products that are compliant with
|
||
the ISO/IEC MPEG audio standards. Please note that most manufacturers of Android devices already license
|
||
these patent claims through Via Licensing or directly from the patent owners, and therefore FDK AAC Codec
|
||
software may already be covered under those patent licenses when it is used for those licensed purposes only.
|
||
|
||
Commercially-licensed AAC software libraries, including floating-point versions with enhanced sound quality,
|
||
are also available from Fraunhofer. Users are encouraged to check the Fraunhofer website for additional
|
||
applications information and documentation.
|
||
|
||
2. COPYRIGHT LICENSE
|
||
|
||
Redistribution and use in source and binary forms, with or without modification, are permitted without
|
||
payment of copyright license fees provided that you satisfy the following conditions:
|
||
|
||
You must retain the complete text of this software license in redistributions of the FDK AAC Codec or
|
||
your modifications thereto in source code form.
|
||
|
||
You must retain the complete text of this software license in the documentation and/or other materials
|
||
provided with redistributions of the FDK AAC Codec or your modifications thereto in binary form.
|
||
You must make available free of charge copies of the complete source code of the FDK AAC Codec and your
|
||
modifications thereto to recipients of copies in binary form.
|
||
|
||
The name of Fraunhofer may not be used to endorse or promote products derived from this library without
|
||
prior written permission.
|
||
|
||
You may not charge copyright license fees for anyone to use, copy or distribute the FDK AAC Codec
|
||
software or your modifications thereto.
|
||
|
||
Your modified versions of the FDK AAC Codec must carry prominent notices stating that you changed the software
|
||
and the date of any change. For modified versions of the FDK AAC Codec, the term
|
||
"Fraunhofer FDK AAC Codec Library for Android" must be replaced by the term
|
||
"Third-Party Modified Version of the Fraunhofer FDK AAC Codec Library for Android."
|
||
|
||
3. NO PATENT LICENSE
|
||
|
||
NO EXPRESS OR IMPLIED LICENSES TO ANY PATENT CLAIMS, including without limitation the patents of Fraunhofer,
|
||
ARE GRANTED BY THIS SOFTWARE LICENSE. Fraunhofer provides no warranty of patent non-infringement with
|
||
respect to this software.
|
||
|
||
You may use this FDK AAC Codec software or modifications thereto only for purposes that are authorized
|
||
by appropriate patent licenses.
|
||
|
||
4. DISCLAIMER
|
||
|
||
This FDK AAC Codec software is provided by Fraunhofer on behalf of the copyright holders and contributors
|
||
"AS IS" and WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES, including but not limited to the implied warranties
|
||
of merchantability and fitness for a particular purpose. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
|
||
CONTRIBUTORS BE LIABLE for any direct, indirect, incidental, special, exemplary, or consequential damages,
|
||
including but not limited to procurement of substitute goods or services; loss of use, data, or profits,
|
||
or business interruption, however caused and on any theory of liability, whether in contract, strict
|
||
liability, or tort (including negligence), arising in any way out of the use of this software, even if
|
||
advised of the possibility of such damage.
|
||
|
||
5. CONTACT INFORMATION
|
||
|
||
Fraunhofer Institute for Integrated Circuits IIS
|
||
Attention: Audio and Multimedia Departments - FDK AAC LL
|
||
Am Wolfsmantel 33
|
||
91058 Erlangen, Germany
|
||
|
||
www.iis.fraunhofer.de/amm
|
||
amm-info@iis.fraunhofer.de
|
||
----------------------------------------------------------------------------------------------------------- */
|
||
|
||
/***************************** MPEG-4 AAC Decoder **************************
|
||
|
||
Author(s): Josef Hoepfl
|
||
Description: joint stereo processing
|
||
|
||
******************************************************************************/
|
||
|
||
#include "stereo.h"
|
||
|
||
|
||
#include "aac_rom.h"
|
||
#include "FDK_bitstream.h"
|
||
#include "channelinfo.h"
|
||
|
||
enum
|
||
{
|
||
L = 0,
|
||
R = 1
|
||
};
|
||
|
||
|
||
int CJointStereo_Read(
|
||
HANDLE_FDK_BITSTREAM bs,
|
||
CJointStereoData *pJointStereoData,
|
||
const int windowGroups,
|
||
const int scaleFactorBandsTransmitted,
|
||
const UINT flags
|
||
)
|
||
{
|
||
int group,band;
|
||
|
||
pJointStereoData->MsMaskPresent = (UCHAR) FDKreadBits(bs,2);
|
||
|
||
FDKmemclear(pJointStereoData->MsUsed, scaleFactorBandsTransmitted*sizeof(UCHAR));
|
||
|
||
switch (pJointStereoData->MsMaskPresent)
|
||
{
|
||
case 0 : /* no M/S */
|
||
/* all flags are already cleared */
|
||
break ;
|
||
|
||
case 1 : /* read ms_used */
|
||
|
||
for (group=0; group<windowGroups; group++)
|
||
{
|
||
for (band=0; band<scaleFactorBandsTransmitted; band++)
|
||
{
|
||
pJointStereoData->MsUsed[band] |= (FDKreadBits(bs,1) << group);
|
||
}
|
||
}
|
||
break ;
|
||
|
||
case 2 : /* full spectrum M/S */
|
||
|
||
for (band=0; band<scaleFactorBandsTransmitted; band++)
|
||
{
|
||
pJointStereoData->MsUsed[band] = 255 ; /* set all flags to 1 */
|
||
}
|
||
break ;
|
||
}
|
||
|
||
return 0;
|
||
}
|
||
|
||
void CJointStereo_ApplyMS(
|
||
CAacDecoderChannelInfo *pAacDecoderChannelInfo[2],
|
||
const SHORT *pScaleFactorBandOffsets,
|
||
const UCHAR *pWindowGroupLength,
|
||
const int windowGroups,
|
||
const int scaleFactorBandsTransmittedL,
|
||
const int scaleFactorBandsTransmittedR
|
||
)
|
||
{
|
||
CJointStereoData *pJointStereoData = &pAacDecoderChannelInfo[L]->pComData->jointStereoData;
|
||
int window, group, scaleFactorBandsTransmitted;
|
||
|
||
FDK_ASSERT(scaleFactorBandsTransmittedL == scaleFactorBandsTransmittedR);
|
||
scaleFactorBandsTransmitted = scaleFactorBandsTransmittedL;
|
||
for (window = 0, group = 0; group < windowGroups; group++)
|
||
{
|
||
UCHAR groupMask = 1 << group;
|
||
|
||
for (int groupwin=0; groupwin<pWindowGroupLength[group]; groupwin++, window++)
|
||
{
|
||
int band;
|
||
FIXP_DBL *leftSpectrum, *rightSpectrum;
|
||
SHORT *leftScale = &pAacDecoderChannelInfo[L]->pDynData->aSfbScale[window*16];
|
||
SHORT *rightScale = &pAacDecoderChannelInfo[R]->pDynData->aSfbScale[window*16];
|
||
|
||
leftSpectrum = SPEC(pAacDecoderChannelInfo[L]->pSpectralCoefficient, window, pAacDecoderChannelInfo[L]->granuleLength);
|
||
rightSpectrum = SPEC(pAacDecoderChannelInfo[R]->pSpectralCoefficient, window, pAacDecoderChannelInfo[R]->granuleLength);
|
||
|
||
for (band=0; band<scaleFactorBandsTransmitted; band++)
|
||
{
|
||
if (pJointStereoData->MsUsed[band] & groupMask)
|
||
{
|
||
int lScale=leftScale[band];
|
||
int rScale=rightScale[band];
|
||
int commonScale=lScale > rScale ? lScale:rScale;
|
||
|
||
/* ISO/IEC 14496-3 Chapter 4.6.8.1.1 :
|
||
M/S joint channel coding can only be used if common_window is ‘1’. */
|
||
FDK_ASSERT(GetWindowSequence(&pAacDecoderChannelInfo[L]->icsInfo) == GetWindowSequence(&pAacDecoderChannelInfo[R]->icsInfo));
|
||
FDK_ASSERT(GetWindowShape(&pAacDecoderChannelInfo[L]->icsInfo) == GetWindowShape(&pAacDecoderChannelInfo[R]->icsInfo));
|
||
|
||
commonScale++;
|
||
leftScale[band]=commonScale;
|
||
rightScale[band]=commonScale;
|
||
|
||
lScale = fMin(DFRACT_BITS-1, commonScale - lScale);
|
||
rScale = fMin(DFRACT_BITS-1, commonScale - rScale);
|
||
|
||
FDK_ASSERT(lScale >= 0 && rScale >= 0);
|
||
|
||
for (int index=pScaleFactorBandOffsets[band]; index<pScaleFactorBandOffsets[band+1]; index++)
|
||
{
|
||
FIXP_DBL leftCoefficient = leftSpectrum [index] ;
|
||
FIXP_DBL rightCoefficient = rightSpectrum [index] ;
|
||
|
||
leftCoefficient >>= lScale ;
|
||
rightCoefficient >>= rScale ;
|
||
|
||
leftSpectrum [index] = leftCoefficient + rightCoefficient ;
|
||
rightSpectrum [index] = leftCoefficient - rightCoefficient ;
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Reset MsUsed flags if no explicit signalling was transmitted. Necessary for intensity coding.
|
||
PNS correlation signalling was mapped before calling CJointStereo_ApplyMS(). */
|
||
if (pJointStereoData->MsMaskPresent == 2) {
|
||
FDKmemclear(pJointStereoData->MsUsed, JointStereoMaximumBands * sizeof(UCHAR));
|
||
}
|
||
}
|
||
|
||
void CJointStereo_ApplyIS(
|
||
CAacDecoderChannelInfo *pAacDecoderChannelInfo[2],
|
||
const SHORT *pScaleFactorBandOffsets,
|
||
const UCHAR *pWindowGroupLength,
|
||
const int windowGroups,
|
||
const int scaleFactorBandsTransmitted,
|
||
const UINT CommonWindow
|
||
)
|
||
{
|
||
CJointStereoData *pJointStereoData = &pAacDecoderChannelInfo[L]->pComData->jointStereoData;
|
||
|
||
for (int window=0,group=0; group<windowGroups; group++)
|
||
{
|
||
UCHAR *CodeBook;
|
||
SHORT *ScaleFactor;
|
||
UCHAR groupMask = 1 << group;
|
||
|
||
CodeBook = &pAacDecoderChannelInfo[R]->pDynData->aCodeBook[group*16];
|
||
ScaleFactor = &pAacDecoderChannelInfo[R]->pDynData->aScaleFactor[group*16];
|
||
|
||
for (int groupwin=0; groupwin<pWindowGroupLength[group]; groupwin++, window++)
|
||
{
|
||
FIXP_DBL *leftSpectrum, *rightSpectrum;
|
||
SHORT *leftScale = &pAacDecoderChannelInfo[L]->pDynData->aSfbScale[window*16];
|
||
SHORT *rightScale = &pAacDecoderChannelInfo[R]->pDynData->aSfbScale[window*16];
|
||
int band;
|
||
|
||
leftSpectrum = SPEC(pAacDecoderChannelInfo[L]->pSpectralCoefficient, window, pAacDecoderChannelInfo[L]->granuleLength);
|
||
rightSpectrum = SPEC(pAacDecoderChannelInfo[R]->pSpectralCoefficient, window, pAacDecoderChannelInfo[R]->granuleLength);
|
||
|
||
for (band=0; band<scaleFactorBandsTransmitted; band++)
|
||
{
|
||
if ((CodeBook [band] == INTENSITY_HCB) ||
|
||
(CodeBook [band] == INTENSITY_HCB2))
|
||
{
|
||
int bandScale = -(ScaleFactor [band] + 100) ;
|
||
|
||
int msb = bandScale >> 2 ;
|
||
int lsb = bandScale & 0x03 ;
|
||
|
||
/* exponent of MantissaTable[lsb][0] is 1, thus msb+1 below. */
|
||
FIXP_DBL scale = MantissaTable[lsb][0];
|
||
|
||
/* ISO/IEC 14496-3 Chapter 4.6.8.2.3 :
|
||
The use of intensity stereo coding is signaled by the use of the pseudo codebooks
|
||
INTENSITY_HCB and INTENSITY_HCB2 (15 and 14) only in the right channel of a
|
||
channel_pair_element() having a common ics_info() (common_window == 1). */
|
||
FDK_ASSERT(GetWindowSequence(&pAacDecoderChannelInfo[L]->icsInfo) == GetWindowSequence(&pAacDecoderChannelInfo[R]->icsInfo));
|
||
FDK_ASSERT(GetWindowShape(&pAacDecoderChannelInfo[L]->icsInfo) == GetWindowShape(&pAacDecoderChannelInfo[R]->icsInfo));
|
||
|
||
rightScale[band] = leftScale[band]+msb+1;
|
||
|
||
if (CommonWindow && (pJointStereoData->MsUsed[band] & groupMask))
|
||
{
|
||
|
||
if (CodeBook[band] == INTENSITY_HCB) /* _NOT_ in-phase */
|
||
{
|
||
scale = -scale ;
|
||
}
|
||
}
|
||
else
|
||
{
|
||
if (CodeBook[band] == INTENSITY_HCB2) /* out-of-phase */
|
||
{
|
||
scale = -scale ;
|
||
}
|
||
}
|
||
|
||
for (int index=pScaleFactorBandOffsets[band]; index<pScaleFactorBandOffsets[band+1]; index++)
|
||
{
|
||
rightSpectrum[index] = fMult(leftSpectrum[index],scale);
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|
||
}
|