| /* ----------------------------------------------------------------------------- |
| Software License for The Fraunhofer FDK AAC Codec Library for Android |
| |
| © Copyright 1995 - 2018 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 |
| ----------------------------------------------------------------------------- */ |
| |
| /******************* Library for basic calculation routines ******************** |
| |
| Author(s): |
| |
| Description: dit_fft ARM assembler replacements. |
| |
| *******************************************************************************/ |
| |
| #ifndef __FFT_RAD2_CPP__ |
| #error \ |
| "Do not compile this file separately. It is included on demand from fft_rad2.cpp" |
| #endif |
| |
| #ifndef FUNCTION_dit_fft |
| #if defined(SINETABLE_16BIT) |
| |
| #define FUNCTION_dit_fft |
| #if defined(FUNCTION_dit_fft) |
| |
| void dit_fft(FIXP_DBL *x, const INT ldn, const FIXP_STP *trigdata, |
| const INT trigDataSize) { |
| const INT n = 1 << ldn; |
| INT i; |
| |
| scramble(x, n); |
| /* |
| * 1+2 stage radix 4 |
| */ |
| |
| for (i = 0; i < n * 2; i += 8) { |
| FIXP_DBL a00, a10, a20, a30; |
| a00 = (x[i + 0] + x[i + 2]) >> 1; /* Re A + Re B */ |
| a10 = (x[i + 4] + x[i + 6]) >> 1; /* Re C + Re D */ |
| a20 = (x[i + 1] + x[i + 3]) >> 1; /* Im A + Im B */ |
| a30 = (x[i + 5] + x[i + 7]) >> 1; /* Im C + Im D */ |
| |
| x[i + 0] = a00 + a10; /* Re A' = Re A + Re B + Re C + Re D */ |
| x[i + 4] = a00 - a10; /* Re C' = Re A + Re B - Re C - Re D */ |
| x[i + 1] = a20 + a30; /* Im A' = Im A + Im B + Im C + Im D */ |
| x[i + 5] = a20 - a30; /* Im C' = Im A + Im B - Im C - Im D */ |
| |
| a00 = a00 - x[i + 2]; /* Re A - Re B */ |
| a10 = a10 - x[i + 6]; /* Re C - Re D */ |
| a20 = a20 - x[i + 3]; /* Im A - Im B */ |
| a30 = a30 - x[i + 7]; /* Im C - Im D */ |
| |
| x[i + 2] = a00 + a30; /* Re B' = Re A - Re B + Im C - Im D */ |
| x[i + 6] = a00 - a30; /* Re D' = Re A - Re B - Im C + Im D */ |
| x[i + 3] = a20 - a10; /* Im B' = Im A - Im B - Re C + Re D */ |
| x[i + 7] = a20 + a10; /* Im D' = Im A - Im B + Re C - Re D */ |
| } |
| |
| INT mh = 1 << 1; |
| INT ldm = ldn - 2; |
| INT trigstep = trigDataSize; |
| |
| do { |
| const FIXP_STP *pTrigData = trigdata; |
| INT j; |
| |
| mh <<= 1; |
| trigstep >>= 1; |
| |
| FDK_ASSERT(trigstep > 0); |
| |
| /* Do first iteration with c=1.0 and s=0.0 separately to avoid loosing to |
| much precision. Beware: The impact on the overal FFT precision is rather |
| large. */ |
| { |
| FIXP_DBL *xt1 = x; |
| int r = n; |
| |
| do { |
| FIXP_DBL *xt2 = xt1 + (mh << 1); |
| /* |
| FIXP_DBL *xt1 = x+ ((r)<<1); |
| FIXP_DBL *xt2 = xt1 + (mh<<1); |
| */ |
| FIXP_DBL vr, vi, ur, ui; |
| |
| // cplxMultDiv2(&vi, &vr, x[t2+1], x[t2], (FIXP_SGL)1.0, (FIXP_SGL)0.0); |
| vi = xt2[1] >> 1; |
| vr = xt2[0] >> 1; |
| |
| ur = xt1[0] >> 1; |
| ui = xt1[1] >> 1; |
| |
| xt1[0] = ur + vr; |
| xt1[1] = ui + vi; |
| |
| xt2[0] = ur - vr; |
| xt2[1] = ui - vi; |
| |
| xt1 += mh; |
| xt2 += mh; |
| |
| // cplxMultDiv2(&vr, &vi, x[t2+1], x[t2], (FIXP_SGL)1.0, (FIXP_SGL)0.0); |
| vr = xt2[1] >> 1; |
| vi = xt2[0] >> 1; |
| |
| ur = xt1[0] >> 1; |
| ui = xt1[1] >> 1; |
| |
| xt1[0] = ur + vr; |
| xt1[1] = ui - vi; |
| |
| xt2[0] = ur - vr; |
| xt2[1] = ui + vi; |
| |
| xt1 = xt2 + mh; |
| } while ((r = r - (mh << 1)) != 0); |
| } |
| for (j = 4; j < mh; j += 4) { |
| FIXP_DBL *xt1 = x + (j >> 1); |
| FIXP_SPK cs; |
| int r = n; |
| |
| pTrigData += trigstep; |
| cs = *pTrigData; |
| |
| do { |
| FIXP_DBL *xt2 = xt1 + (mh << 1); |
| FIXP_DBL vr, vi, ur, ui; |
| |
| cplxMultDiv2(&vi, &vr, xt2[1], xt2[0], cs); |
| |
| ur = xt1[0] >> 1; |
| ui = xt1[1] >> 1; |
| |
| xt1[0] = ur + vr; |
| xt1[1] = ui + vi; |
| |
| xt2[0] = ur - vr; |
| xt2[1] = ui - vi; |
| |
| xt1 += mh; |
| xt2 += mh; |
| |
| cplxMultDiv2(&vr, &vi, xt2[1], xt2[0], cs); |
| |
| ur = xt1[0] >> 1; |
| ui = xt1[1] >> 1; |
| |
| xt1[0] = ur + vr; |
| xt1[1] = ui - vi; |
| |
| xt2[0] = ur - vr; |
| xt2[1] = ui + vi; |
| |
| /* Same as above but for t1,t2 with j>mh/4 and thus cs swapped */ |
| xt1 = xt1 - (j); |
| xt2 = xt1 + (mh << 1); |
| |
| cplxMultDiv2(&vi, &vr, xt2[0], xt2[1], cs); |
| |
| ur = xt1[0] >> 1; |
| ui = xt1[1] >> 1; |
| |
| xt1[0] = ur + vr; |
| xt1[1] = ui - vi; |
| |
| xt2[0] = ur - vr; |
| xt2[1] = ui + vi; |
| |
| xt1 += mh; |
| xt2 += mh; |
| |
| cplxMultDiv2(&vr, &vi, xt2[0], xt2[1], cs); |
| |
| ur = xt1[0] >> 1; |
| ui = xt1[1] >> 1; |
| |
| xt1[0] = ur - vr; |
| xt1[1] = ui - vi; |
| |
| xt2[0] = ur + vr; |
| xt2[1] = ui + vi; |
| |
| xt1 = xt2 + (j); |
| } while ((r = r - (mh << 1)) != 0); |
| } |
| { |
| FIXP_DBL *xt1 = x + (mh >> 1); |
| int r = n; |
| |
| do { |
| FIXP_DBL *xt2 = xt1 + (mh << 1); |
| FIXP_DBL vr, vi, ur, ui; |
| |
| cplxMultDiv2(&vi, &vr, xt2[1], xt2[0], STC(0x5a82799a), |
| STC(0x5a82799a)); |
| |
| ur = xt1[0] >> 1; |
| ui = xt1[1] >> 1; |
| |
| xt1[0] = ur + vr; |
| xt1[1] = ui + vi; |
| |
| xt2[0] = ur - vr; |
| xt2[1] = ui - vi; |
| |
| xt1 += mh; |
| xt2 += mh; |
| |
| cplxMultDiv2(&vr, &vi, xt2[1], xt2[0], STC(0x5a82799a), |
| STC(0x5a82799a)); |
| |
| ur = xt1[0] >> 1; |
| ui = xt1[1] >> 1; |
| |
| xt1[0] = ur + vr; |
| xt1[1] = ui - vi; |
| |
| xt2[0] = ur - vr; |
| xt2[1] = ui + vi; |
| |
| xt1 = xt2 + mh; |
| } while ((r = r - (mh << 1)) != 0); |
| } |
| } while (--ldm != 0); |
| } |
| |
| #endif /* if defined(FUNCTION_dit_fft) */ |
| |
| #endif /* if defined(SINETABLE_16BIT) */ |
| |
| #endif /* ifndef FUNCTION_dit_fft */ |