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Diffstat (limited to 'fdk-aac/libFDK/src/autocorr2nd.cpp')
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diff --git a/fdk-aac/libFDK/src/autocorr2nd.cpp b/fdk-aac/libFDK/src/autocorr2nd.cpp new file mode 100644 index 0000000..718a555 --- /dev/null +++ b/fdk-aac/libFDK/src/autocorr2nd.cpp @@ -0,0 +1,293 @@ +/* ----------------------------------------------------------------------------- +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): M. Lohwasser + + Description: auto-correlation functions + +*******************************************************************************/ + +#include "autocorr2nd.h" + +/* If the accumulator does not provide enough overflow bits, + products have to be shifted down in the autocorrelation below. */ +#define SHIFT_FACTOR (5) +#define SHIFT >> (SHIFT_FACTOR) + +/*! + * + * \brief Calculate second order autocorrelation using 2 accumulators + * + */ +#if !defined(FUNCTION_autoCorr2nd_real) +INT autoCorr2nd_real( + ACORR_COEFS *ac, /*!< Pointer to autocorrelation coeffs */ + const FIXP_DBL *reBuffer, /*!< Pointer to to real part of input samples */ + const int len /*!< Number input samples */ +) { + int j, autoCorrScaling, mScale; + + FIXP_DBL accu1, accu2, accu3, accu4, accu5; + + const FIXP_DBL *pReBuf; + + const FIXP_DBL *realBuf = reBuffer; + + /* + r11r,r22r + r01r,r12r + r02r + */ + pReBuf = realBuf - 2; + accu5 = ((fMultDiv2(pReBuf[0], pReBuf[2]) + fMultDiv2(pReBuf[1], pReBuf[3])) + SHIFT); + pReBuf++; + + /* len must be even */ + accu1 = fPow2Div2(pReBuf[0]) SHIFT; + accu3 = fMultDiv2(pReBuf[0], pReBuf[1]) SHIFT; + pReBuf++; + + for (j = (len - 2) >> 1; j != 0; j--, pReBuf += 2) { + accu1 += ((fPow2Div2(pReBuf[0]) + fPow2Div2(pReBuf[1])) SHIFT); + + accu3 += ((fMultDiv2(pReBuf[0], pReBuf[1]) + + fMultDiv2(pReBuf[1], pReBuf[2])) SHIFT); + + accu5 += ((fMultDiv2(pReBuf[0], pReBuf[2]) + + fMultDiv2(pReBuf[1], pReBuf[3])) SHIFT); + } + + accu2 = (fPow2Div2(realBuf[-2]) SHIFT); + accu2 += accu1; + + accu1 += (fPow2Div2(realBuf[len - 2]) SHIFT); + + accu4 = (fMultDiv2(realBuf[-1], realBuf[-2]) SHIFT); + accu4 += accu3; + + accu3 += (fMultDiv2(realBuf[len - 1], realBuf[len - 2]) SHIFT); + + mScale = CntLeadingZeros( + (accu1 | accu2 | fAbs(accu3) | fAbs(accu4) | fAbs(accu5))) - + 1; + autoCorrScaling = mScale - 1 - SHIFT_FACTOR; /* -1 because of fMultDiv2*/ + + /* Scale to common scale factor */ + ac->r11r = accu1 << mScale; + ac->r22r = accu2 << mScale; + ac->r01r = accu3 << mScale; + ac->r12r = accu4 << mScale; + ac->r02r = accu5 << mScale; + + ac->det = (fMultDiv2(ac->r11r, ac->r22r) - fMultDiv2(ac->r12r, ac->r12r)); + mScale = CountLeadingBits(fAbs(ac->det)); + + ac->det <<= mScale; + ac->det_scale = mScale - 1; + + return autoCorrScaling; +} +#endif + +#if !defined(FUNCTION_autoCorr2nd_cplx) +INT autoCorr2nd_cplx( + ACORR_COEFS *ac, /*!< Pointer to autocorrelation coeffs */ + const FIXP_DBL *reBuffer, /*!< Pointer to real part of input samples */ + const FIXP_DBL *imBuffer, /*!< Pointer to imag part of input samples */ + const int len /*!< Number of input samples (should be smaller than 128) */ +) { + int j, autoCorrScaling, mScale, len_scale; + + FIXP_DBL accu0, accu1, accu2, accu3, accu4, accu5, accu6, accu7, accu8; + + const FIXP_DBL *pReBuf, *pImBuf; + + const FIXP_DBL *realBuf = reBuffer; + const FIXP_DBL *imagBuf = imBuffer; + + (len > 64) ? (len_scale = 6) : (len_scale = 5); + /* + r00r, + r11r,r22r + r01r,r12r + r01i,r12i + r02r,r02i + */ + accu1 = accu3 = accu5 = accu7 = accu8 = FL2FXCONST_DBL(0.0f); + + pReBuf = realBuf - 2, pImBuf = imagBuf - 2; + accu7 += + ((fMultDiv2(pReBuf[2], pReBuf[0]) + fMultDiv2(pImBuf[2], pImBuf[0])) >> + len_scale); + accu8 += + ((fMultDiv2(pImBuf[2], pReBuf[0]) - fMultDiv2(pReBuf[2], pImBuf[0])) >> + len_scale); + + pReBuf = realBuf - 1, pImBuf = imagBuf - 1; + for (j = (len - 1); j != 0; j--, pReBuf++, pImBuf++) { + accu1 += ((fPow2Div2(pReBuf[0]) + fPow2Div2(pImBuf[0])) >> len_scale); + accu3 += + ((fMultDiv2(pReBuf[0], pReBuf[1]) + fMultDiv2(pImBuf[0], pImBuf[1])) >> + len_scale); + accu5 += + ((fMultDiv2(pImBuf[1], pReBuf[0]) - fMultDiv2(pReBuf[1], pImBuf[0])) >> + len_scale); + accu7 += + ((fMultDiv2(pReBuf[2], pReBuf[0]) + fMultDiv2(pImBuf[2], pImBuf[0])) >> + len_scale); + accu8 += + ((fMultDiv2(pImBuf[2], pReBuf[0]) - fMultDiv2(pReBuf[2], pImBuf[0])) >> + len_scale); + } + + accu2 = ((fPow2Div2(realBuf[-2]) + fPow2Div2(imagBuf[-2])) >> len_scale); + accu2 += accu1; + + accu1 += ((fPow2Div2(realBuf[len - 2]) + fPow2Div2(imagBuf[len - 2])) >> + len_scale); + accu0 = ((fPow2Div2(realBuf[len - 1]) + fPow2Div2(imagBuf[len - 1])) >> + len_scale) - + ((fPow2Div2(realBuf[-1]) + fPow2Div2(imagBuf[-1])) >> len_scale); + accu0 += accu1; + + accu4 = ((fMultDiv2(realBuf[-1], realBuf[-2]) + + fMultDiv2(imagBuf[-1], imagBuf[-2])) >> + len_scale); + accu4 += accu3; + + accu3 += ((fMultDiv2(realBuf[len - 1], realBuf[len - 2]) + + fMultDiv2(imagBuf[len - 1], imagBuf[len - 2])) >> + len_scale); + + accu6 = ((fMultDiv2(imagBuf[-1], realBuf[-2]) - + fMultDiv2(realBuf[-1], imagBuf[-2])) >> + len_scale); + accu6 += accu5; + + accu5 += ((fMultDiv2(imagBuf[len - 1], realBuf[len - 2]) - + fMultDiv2(realBuf[len - 1], imagBuf[len - 2])) >> + len_scale); + + mScale = + CntLeadingZeros((accu0 | accu1 | accu2 | fAbs(accu3) | fAbs(accu4) | + fAbs(accu5) | fAbs(accu6) | fAbs(accu7) | fAbs(accu8))) - + 1; + autoCorrScaling = mScale - 1 - len_scale; /* -1 because of fMultDiv2*/ + + /* Scale to common scale factor */ + ac->r00r = (FIXP_DBL)accu0 << mScale; + ac->r11r = (FIXP_DBL)accu1 << mScale; + ac->r22r = (FIXP_DBL)accu2 << mScale; + ac->r01r = (FIXP_DBL)accu3 << mScale; + ac->r12r = (FIXP_DBL)accu4 << mScale; + ac->r01i = (FIXP_DBL)accu5 << mScale; + ac->r12i = (FIXP_DBL)accu6 << mScale; + ac->r02r = (FIXP_DBL)accu7 << mScale; + ac->r02i = (FIXP_DBL)accu8 << mScale; + + ac->det = + (fMultDiv2(ac->r11r, ac->r22r) >> 1) - + ((fMultDiv2(ac->r12r, ac->r12r) + fMultDiv2(ac->r12i, ac->r12i)) >> 1); + mScale = CntLeadingZeros(fAbs(ac->det)) - 1; + + ac->det <<= mScale; + ac->det_scale = mScale - 2; + + return autoCorrScaling; +} + +#endif /* FUNCTION_autoCorr2nd_cplx */ |