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| /* ----------------------------------------------------------------------------------------------------------- |
| 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 |
| ----------------------------------------------------------------------------------------------------------- */ |
| |
| /***************************************************************************** |
| |
| Description: FDKaacLdEnc_MdctTransform480: |
| The module FDKaacLdEnc_MdctTransform will perform the MDCT. |
| The MDCT supports the sine window and |
| the zero padded window. The algorithm of the MDCT |
| can be divided in Windowing, PreModulation, Fft and |
| PostModulation. |
| |
| ******************************************************************************/ |
| |
| #include "transform.h" |
| |
| #include "dct.h" |
| #include "psy_const.h" |
| #include "aacEnc_rom.h" |
| #include "FDK_tools_rom.h" |
| |
| INT FDKaacEnc_Transform_Real (const INT_PCM * pTimeData, |
| FIXP_DBL *RESTRICT mdctData, |
| const INT blockType, |
| const INT windowShape, |
| INT *prevWindowShape, |
| const INT frameLength, |
| INT *mdctData_e, |
| INT filterType |
| ,FIXP_DBL * RESTRICT overlapAddBuffer |
| ) |
| { |
| const INT_PCM * RESTRICT timeData; |
| |
| INT i; |
| /* tl: transform length |
| fl: left window slope length |
| nl: left window slope offset |
| fr: right window slope length |
| nr: right window slope offset |
| See FDK_tools/doc/intern/mdct.tex for more detail. */ |
| int tl, fl, nl, fr, nr; |
| |
| const FIXP_WTP * RESTRICT pLeftWindowPart; |
| const FIXP_WTP * RESTRICT pRightWindowPart; |
| |
| /* |
| * MDCT scale: |
| * + 1: fMultDiv2() in windowing. |
| * + 1: Because of factor 1/2 in Princen-Bradley compliant windowed TDAC. |
| */ |
| *mdctData_e = 1+1; |
| |
| tl = frameLength; |
| timeData = pTimeData; |
| |
| switch( blockType ) { |
| case LONG_WINDOW: |
| { |
| int offset = (windowShape == LOL_WINDOW) ? ((frameLength * 3)>>2) : 0; |
| fl = frameLength - offset; |
| fr = frameLength - offset; |
| } |
| break; |
| case STOP_WINDOW: |
| fl = frameLength >> 3; |
| fr = frameLength; |
| break; |
| case START_WINDOW: /* or StopStartSequence */ |
| fl = frameLength; |
| fr = frameLength >> 3; |
| break; |
| case SHORT_WINDOW: |
| fl = fr = frameLength >> 3; |
| tl >>= 3; |
| timeData = pTimeData + 3*fl + (fl/2); |
| break; |
| default: |
| FDK_ASSERT(0); |
| return -1; |
| break; |
| } |
| |
| /* Taken from FDK_tools/src/mdct.cpp Derive NR and NL */ |
| nr = (tl - fr)>>1; |
| nl = (tl - fl)>>1; |
| |
| pLeftWindowPart = FDKgetWindowSlope(fl, *prevWindowShape); |
| pRightWindowPart = FDKgetWindowSlope(fr, windowShape); |
| |
| /* windowing */ |
| if (filterType != FB_ELD) |
| { |
| /* Left window slope offset */ |
| for (i=0; i<nl ; i++) |
| { |
| #if SAMPLE_BITS == DFRACT_BITS /* SPC_BITS and DFRACT_BITS should be equal. */ |
| mdctData[(tl/2)+i] = - (FIXP_DBL) timeData[tl-i-1] >> ( 1 ); |
| #else |
| mdctData[(tl/2)+i] = - (FIXP_DBL) timeData[tl-i-1] << (DFRACT_BITS - SAMPLE_BITS - 1); |
| #endif |
| } |
| /* Left window slope */ |
| for (i=0; i<fl/2; i++) |
| { |
| FIXP_DBL tmp0; |
| tmp0 = fMultDiv2((FIXP_PCM)timeData[i+nl], pLeftWindowPart[i].v.im); |
| mdctData[(tl/2)+i+nl] = fMultSubDiv2(tmp0, (FIXP_PCM)timeData[tl-nl-i-1], pLeftWindowPart[i].v.re); |
| } |
| |
| /* Right window slope offset */ |
| for(i=0; i<nr; i++) |
| { |
| #if SAMPLE_BITS == DFRACT_BITS /* This should be SPC_BITS instead of DFRACT_BITS. */ |
| mdctData[(tl/2)-1-i] = - (FIXP_DBL) timeData[tl+i] >> (1); |
| #else |
| mdctData[(tl/2)-1-i] = - (FIXP_DBL) timeData[tl+i] << (DFRACT_BITS - SAMPLE_BITS - 1); |
| #endif |
| } |
| /* Right window slope */ |
| for (i=0; i<fr/2; i++) |
| { |
| FIXP_DBL tmp1; |
| tmp1 = fMultDiv2((FIXP_PCM)timeData[tl+nr+i], pRightWindowPart[i].v.re); |
| mdctData[(tl/2)-nr-i-1] = -fMultAddDiv2(tmp1, (FIXP_PCM)timeData[(tl*2)-nr-i-1], pRightWindowPart[i].v.im); |
| } |
| } |
| |
| if (filterType == FB_ELD) |
| { |
| const FIXP_WTB *pWindowELD=NULL; |
| int i, N = frameLength, L = frameLength; |
| |
| if (frameLength == 512) { |
| pWindowELD = ELDAnalysis512; |
| } else { |
| pWindowELD = ELDAnalysis480; |
| } |
| |
| for(i=0;i<N/4;i++) |
| { |
| FIXP_DBL z0, outval; |
| |
| z0 = (fMult((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N/2-1-i])<< (WTS0-1)) + (fMult((FIXP_PCM)timeData[L+N*3/4+i], pWindowELD[N/2+i])<< (WTS0-1)); |
| |
| outval = (fMultDiv2((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N+N/2-1-i]) >> (-WTS1)); |
| outval += (fMultDiv2((FIXP_PCM)timeData[L+N*3/4+i], pWindowELD[N+N/2+i]) >> (-WTS1) ); |
| outval += (fMultDiv2(overlapAddBuffer[N/2+i], pWindowELD[2*N+i])>> (-WTS2-1)); |
| |
| overlapAddBuffer[N/2+i] = overlapAddBuffer[i]; |
| |
| overlapAddBuffer[i] = z0; |
| mdctData[i] = overlapAddBuffer[N/2+i] + (fMultDiv2(overlapAddBuffer[N+N/2-1-i], pWindowELD[2*N+N/2+i]) >> (-WTS2-1)); |
| |
| mdctData[N-1-i] = outval; |
| overlapAddBuffer[N+N/2-1-i] = outval; |
| } |
| |
| for(i=N/4;i<N/2;i++) |
| { |
| FIXP_DBL z0, outval; |
| |
| z0 = fMult((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N/2-1-i]) << (WTS0-1); |
| |
| outval = (fMultDiv2((FIXP_PCM)timeData[L+N*3/4-1-i], pWindowELD[N+N/2-1-i]) >> (-WTS1)) ; |
| outval += (fMultDiv2(overlapAddBuffer[N/2+i], pWindowELD[2*N+i]) >> (-WTS2-1)); |
| |
| overlapAddBuffer[N/2+i] = overlapAddBuffer[i] + (fMult((FIXP_PCM)timeData[L-N/4+i], pWindowELD[N/2+i])<< (WTS0-1) ); |
| |
| overlapAddBuffer[i] = z0; |
| mdctData[i] = overlapAddBuffer[N/2+i] + (fMultDiv2(overlapAddBuffer[N+N/2-1-i], pWindowELD[2*N+N/2+i]) >> (-WTS2-1)); |
| |
| mdctData[N-1-i] = outval; |
| overlapAddBuffer[N+N/2-1-i] = outval; |
| } |
| } |
| |
| dct_IV(mdctData, tl, mdctData_e); |
| |
| *prevWindowShape = windowShape; |
| |
| return 0; |
| } |
| |