18a4af02f9
Change-Id: I42a702487e6db4953dca0027710ea4fe266052fd Also: - Removed dead code in several source files. - Minor changes in comments. - No functional changes. No changes in executed code. - Added documentation PDFs.
162 lines
7.4 KiB
C++
162 lines
7.4 KiB
C++
|
|
/* -----------------------------------------------------------------------------------------------------------
|
|
Software License for The Fraunhofer FDK AAC Codec Library for Android
|
|
|
|
© Copyright 1995 - 2012 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 Audio Encoder **************************
|
|
|
|
Initial author: M. Werner
|
|
contents/description: Chaos measure calculation
|
|
|
|
******************************************************************************/
|
|
|
|
#include "chaosmeasure.h"
|
|
|
|
/*****************************************************************************
|
|
functionname: FDKaacEnc_FDKaacEnc_CalculateChaosMeasurePeakFast
|
|
description: Eberlein method of chaos measure calculation by high-pass
|
|
filtering amplitude spectrum
|
|
A special case of FDKaacEnc_CalculateChaosMeasureTonalGeneric --
|
|
highly optimized
|
|
*****************************************************************************/
|
|
static void
|
|
FDKaacEnc_FDKaacEnc_CalculateChaosMeasurePeakFast( FIXP_DBL *RESTRICT paMDCTDataNM0,
|
|
INT numberOfLines,
|
|
FIXP_DBL *RESTRICT chaosMeasure )
|
|
{
|
|
INT i, j;
|
|
|
|
/* calculate chaos measure by "peak filter" */
|
|
for (i=0; i<2; i++) {
|
|
/* make even and odd pass through data */
|
|
FIXP_DBL left,center; /* left, center tap of filter */
|
|
|
|
left = (FIXP_DBL)((LONG)paMDCTDataNM0[i]^((LONG)paMDCTDataNM0[i]>>(DFRACT_BITS-1)));
|
|
center = (FIXP_DBL)((LONG)paMDCTDataNM0[i+2]^((LONG)paMDCTDataNM0[i+2]>>(DFRACT_BITS-1)));
|
|
|
|
for (j = i+2; j < numberOfLines - 2; j+=2) {
|
|
FIXP_DBL right = (FIXP_DBL)((LONG)paMDCTDataNM0[j+2]^((LONG)paMDCTDataNM0[j+2]>>(DFRACT_BITS-1)));
|
|
FIXP_DBL tmp = (left>>1)+(right>>1);
|
|
|
|
if (tmp < center ) {
|
|
INT leadingBits = CntLeadingZeros(center)-1;
|
|
tmp = schur_div(tmp<<leadingBits, center<<leadingBits, 8);
|
|
chaosMeasure[j] = fMult(tmp,tmp);
|
|
}
|
|
else {
|
|
chaosMeasure[j] = (FIXP_DBL)MAXVAL_DBL;
|
|
}
|
|
|
|
left = center;
|
|
center = right;
|
|
}
|
|
}
|
|
|
|
/* provide chaos measure for first few lines */
|
|
chaosMeasure[0] = chaosMeasure[2];
|
|
chaosMeasure[1] = chaosMeasure[2];
|
|
|
|
/* provide chaos measure for last few lines */
|
|
for (i = (numberOfLines-3); i < numberOfLines; i++)
|
|
chaosMeasure[i] = FL2FXCONST_DBL(0.5);
|
|
}
|
|
|
|
|
|
/*****************************************************************************
|
|
functionname: FDKaacEnc_CalculateChaosMeasure
|
|
description: calculates a chaosmeasure for every line, different methods
|
|
are available. 0 means tonal, 1 means noiselike
|
|
returns:
|
|
input: MDCT data, number of lines
|
|
output: chaosMeasure
|
|
*****************************************************************************/
|
|
void
|
|
FDKaacEnc_CalculateChaosMeasure( FIXP_DBL *paMDCTDataNM0,
|
|
INT numberOfLines,
|
|
FIXP_DBL *chaosMeasure )
|
|
|
|
{
|
|
FDKaacEnc_FDKaacEnc_CalculateChaosMeasurePeakFast( paMDCTDataNM0,
|
|
numberOfLines,
|
|
chaosMeasure );
|
|
}
|
|
|