4f0d97057c
- Update disclaimer in all source files. - Increment library version in each FDK sub-module. Bug 9428126 Change-Id: I490b96d4ee472246b01483202b0bb4f1e9c2a5d7
209 lines
8.4 KiB
C++
209 lines
8.4 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
|
|
----------------------------------------------------------------------------------------------------------- */
|
|
|
|
/***************************************************************************\
|
|
*
|
|
* filename: ldfiltbank.c
|
|
* project : MPEG-4 Audio Decoder
|
|
* contents/description: low delay filterbank
|
|
*
|
|
\***************************************************************************/
|
|
|
|
#include "ldfiltbank.h"
|
|
|
|
|
|
#include "aac_rom.h"
|
|
#include "dct.h"
|
|
#include "FDK_tools_rom.h"
|
|
#include "mdct.h"
|
|
|
|
#define LDFB_HEADROOM 2
|
|
|
|
static void multE2_DinvF_fdk(INT_PCM *output, FIXP_DBL* x, const FIXP_WTB* fb, FIXP_DBL* z, const int N, const int stride)
|
|
{
|
|
int i, scale;
|
|
|
|
/* scale for FIXP_DBL -> INT_PCM conversion. */
|
|
scale = (DFRACT_BITS - SAMPLE_BITS) - LDFB_HEADROOM;
|
|
|
|
for(i=0;i<N/4;i++)
|
|
{
|
|
FIXP_DBL z0, z2, tmp;
|
|
|
|
z2 = x[N/2+i];
|
|
z0 = z2 + ( fMultDiv2(z[N/2+i], fb[2*N + i]) >> (-WTS2-1) );
|
|
|
|
z[N/2+i] = x[N/2-1-i] + ( fMultDiv2(z[N + i], fb[2*N + N/2 + i]) >> (-WTS2-1) );
|
|
|
|
tmp = ( fMultDiv2(z[N/2+i], fb[N+N/2-1-i]) + fMultDiv2(z[i], fb[N+N/2+i]) ) ;
|
|
|
|
#if (SAMPLE_BITS <= 16)
|
|
FDK_ASSERT( (-WTS1-1 + scale) >= 0);
|
|
output[(N*3/4-1-i)*stride] = (INT_PCM)SATURATE_RIGHT_SHIFT(tmp, -WTS1-1 + scale, SAMPLE_BITS);
|
|
#else
|
|
FDK_ASSERT( (WTS1+1 - scale) >= 0);
|
|
output[(N*3/4-1-i)*stride] = (INT_PCM)SATURATE_LEFT_SHIFT(tmp, WTS1+1 - scale, SAMPLE_BITS);
|
|
#endif
|
|
|
|
z[i] = z0;
|
|
z[N + i] = z2;
|
|
}
|
|
|
|
for(i=N/4;i<N/2;i++)
|
|
{
|
|
FIXP_DBL z0, z2, tmp0, tmp1;
|
|
|
|
z2 = x[N/2+i];
|
|
z0 = z2 + ( fMultDiv2(z[N/2+i], fb[2*N + i]) >> (-WTS2-1) );
|
|
|
|
z[N/2+i] = x[N/2-1-i] + ( fMultDiv2(z[N + i], fb[2*N + N/2 + i]) >> (-WTS2-1) );
|
|
|
|
tmp0 = ( fMultDiv2(z[N/2+i], fb[N/2-1-i]) + fMultDiv2(z[i], fb[N/2+i]) ) ;
|
|
tmp1 = ( fMultDiv2(z[N/2+i], fb[N+N/2-1-i]) + fMultDiv2(z[i], fb[N+N/2+i]) ) ;
|
|
|
|
#if (SAMPLE_BITS <= 16)
|
|
FDK_ASSERT( (-WTS0-1 + scale) >= 0);
|
|
output[(i-N/4)*stride] = (INT_PCM)SATURATE_RIGHT_SHIFT(tmp0, -WTS0-1 + scale, SAMPLE_BITS);
|
|
output[(N*3/4-1-i)*stride] = (INT_PCM)SATURATE_RIGHT_SHIFT(tmp1, -WTS1-1 + scale, SAMPLE_BITS);
|
|
#else
|
|
FDK_ASSERT( (WTS0+1 - scale) >= 0);
|
|
output[(i-N/4)*stride] = (INT_PCM)SATURATE_LEFT_SHIFT(tmp0, WTS0+1 - scale, SAMPLE_BITS);
|
|
output[(N*3/4-1-i)*stride] = (INT_PCM)SATURATE_LEFT_SHIFT(tmp1, WTS1+1 - scale, SAMPLE_BITS);
|
|
#endif
|
|
z[i] = z0;
|
|
z[N + i] = z2;
|
|
}
|
|
|
|
/* Exchange quarter parts of x to bring them in the "right" order */
|
|
for(i=0;i<N/4;i++)
|
|
{
|
|
FIXP_DBL tmp0 = fMultDiv2(z[i], fb[N/2+i]);
|
|
|
|
#if (SAMPLE_BITS <= 16)
|
|
FDK_ASSERT( (-WTS0-1 + scale) >= 0);
|
|
output[(N*3/4 + i)*stride] = (INT_PCM)SATURATE_RIGHT_SHIFT(tmp0, -WTS0-1 + scale, SAMPLE_BITS);
|
|
#else
|
|
FDK_ASSERT( (WTS0+1 - scale) >= 0);
|
|
output[(N*3/4 + i)*stride] = (INT_PCM)SATURATE_LEFT_SHIFT(tmp0, WTS0+1 - scale, SAMPLE_BITS);
|
|
#endif
|
|
}
|
|
}
|
|
|
|
int InvMdctTransformLowDelay_fdk (FIXP_DBL *mdctData, const int mdctData_e, INT_PCM *output, FIXP_DBL *fs_buffer, const int stride, const int N) {
|
|
|
|
const FIXP_WTB *coef;
|
|
FIXP_DBL gain = (FIXP_DBL)0;
|
|
int scale = mdctData_e + MDCT_OUT_HEADROOM - LDFB_HEADROOM; /* The LDFB_HEADROOM is compensated inside multE2_DinvF_fdk() below */
|
|
|
|
/* Select LD window slope */
|
|
if (N == 512)
|
|
coef = (FIXP_WTB*)LowDelaySynthesis512;
|
|
else
|
|
coef = (FIXP_WTB*)LowDelaySynthesis480;
|
|
|
|
/*
|
|
Apply exponent and 1/N factor.
|
|
Note: "scale" is off by one because for LD_MDCT the window length is twice
|
|
the window length of a regular MDCT. This is corrected inside multE2_DinvF_fdk().
|
|
Refer to ISO/IEC 14496-3:2009 page 277, chapter 4.6.20.2 "Low Delay Window".
|
|
*/
|
|
imdct_gain(&gain, &scale, N);
|
|
|
|
dct_IV(mdctData, N, &scale);
|
|
|
|
if (gain != (FIXP_DBL)0) {
|
|
scaleValuesWithFactor(mdctData, gain, N, scale);
|
|
} else {
|
|
scaleValues(mdctData, N, scale);
|
|
}
|
|
|
|
/* Since all exponent and factors have been applied, current exponent is zero. */
|
|
multE2_DinvF_fdk(output, mdctData, coef, fs_buffer, N, stride);
|
|
|
|
return (1);
|
|
}
|
|
|
|
|
|
|
|
|