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diff --git a/libFDK/src/dct.cpp b/libFDK/src/dct.cpp new file mode 100644 index 0000000..5dc9e78 --- /dev/null +++ b/libFDK/src/dct.cpp @@ -0,0 +1,540 @@ + +/* ----------------------------------------------------------------------------------------------------------- +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 +----------------------------------------------------------------------------------------------------------- */ + +/*! + \file dct.cpp + \brief DCT Implementations + Library functions to calculate standard DCTs. This will most likely be replaced by hand-optimized + functions for the specific target processor. + + Three different implementations of the dct type II and the dct type III transforms are provided. + + By default implementations which are based on a single, standard complex FFT-kernel are used (dctII_f() and dctIII_f()). + These are specifically helpful in cases where optimized FFT libraries are already available. The FFT used in these + implementation is FFT rad2 from FDK_tools. + + Of course, one might also use DCT-libraries should they be available. The DCT and DST + type IV implementations are only available in a version based on a complex FFT kernel. +*/ + +#include "dct.h" + + +#include "FDK_tools_rom.h" +#include "fft.h" + + +#if defined(__arm__) +#include "arm/dct_arm.cpp" +#endif + + +#if !defined(FUNCTION_dct_III) +void dct_III(FIXP_DBL *pDat, /*!< pointer to input/output */ + FIXP_DBL *tmp, /*!< pointer to temporal working buffer */ + int L, /*!< lenght of transform */ + int *pDat_e + ) +{ + FDK_ASSERT(L == 64 || L == 32); + int i; + FIXP_DBL xr, accu1, accu2; + int inc; + int M = L>>1; + int ld_M; + + if (L == 64) ld_M = 5; + else ld_M = 4; + + /* This loop performs multiplication for index i (i*inc) */ + inc = (64/2) >> ld_M; /* 64/L */ + + FIXP_DBL *pTmp_0 = &tmp[2]; + FIXP_DBL *pTmp_1 = &tmp[(M-1)*2]; + + for(i=1; i<M>>1; i++,pTmp_0+=2,pTmp_1-=2) { + + FIXP_DBL accu3,accu4,accu5,accu6; + + cplxMultDiv2(&accu2, &accu1, pDat[L - i], pDat[i], sin_twiddle_L64[i*inc]); + cplxMultDiv2(&accu4, &accu3, pDat[M+i], pDat[M-i], sin_twiddle_L64[(M-i)*inc]); + accu3 >>= 1; accu4 >>= 1; + + /* This method is better for ARM926, that uses operand2 shifted right by 1 always */ + cplxMultDiv2(&accu6, &accu5, (accu3 - (accu1>>1)), ((accu2>>1) + accu4), sin_twiddle_L64[(4*i)*inc]); + xr = (accu1>>1) + accu3; + pTmp_0[0] = (xr>>1) - accu5; + pTmp_1[0] = (xr>>1) + accu5; + + xr = (accu2>>1) - accu4; + pTmp_0[1] = (xr>>1) - accu6; + pTmp_1[1] = -((xr>>1) + accu6); + + } + + xr = fMultDiv2(pDat[M], sin_twiddle_L64[64/2].v.re );/* cos((PI/(2*L))*M); */ + tmp[0] = ((pDat[0]>>1) + xr)>>1; + tmp[1] = ((pDat[0]>>1) - xr)>>1; + + cplxMultDiv2(&accu2, &accu1, pDat[L - (M/2)], pDat[M/2], sin_twiddle_L64[64/4]); + tmp[M] = accu1>>1; + tmp[M+1] = accu2>>1; + + /* dit_fft expects 1 bit scaled input values */ + fft(M, tmp, pDat_e); + + /* ARM926: 12 cycles per 2-iteration, no overhead code by compiler */ + pTmp_1 = &tmp[L]; + for (i = M>>1; i--;) + { + FIXP_DBL tmp1, tmp2, tmp3, tmp4; + tmp1 = *tmp++; + tmp2 = *tmp++; + tmp3 = *--pTmp_1; + tmp4 = *--pTmp_1; + *pDat++ = tmp1; + *pDat++ = tmp3; + *pDat++ = tmp2; + *pDat++ = tmp4; + } + + *pDat_e += 2; +} +#endif + +#if !defined(FUNCTION_dct_II) +void dct_II(FIXP_DBL *pDat, /*!< pointer to input/output */ + FIXP_DBL *tmp, /*!< pointer to temporal working buffer */ + int L, /*!< lenght of transform */ + int *pDat_e + ) +{ + FDK_ASSERT(L == 64 || L == 32); + FIXP_DBL accu1,accu2; + FIXP_DBL *pTmp_0, *pTmp_1; + + int i; + int inc; + int M = L>>1; + int ld_M; + + FDK_ASSERT(L == 64 || L == 32); + ld_M = 4 + (L >> 6); /* L=64: 5, L=32: 4 */ + + inc = (64/2) >> ld_M; /* L=64: 1, L=32: 2 */ + + FIXP_DBL *pdat = &pDat[0]; + FIXP_DBL accu3, accu4; + pTmp_0 = &tmp[0]; + pTmp_1 = &tmp[L-1]; + for (i = M>>1; i--; ) + { + accu1 = *pdat++; + accu2 = *pdat++; + accu3 = *pdat++; + accu4 = *pdat++; + accu1 >>= 1; + accu2 >>= 1; + accu3 >>= 1; + accu4 >>= 1; + *pTmp_0++ = accu1; + *pTmp_0++ = accu3; + *pTmp_1-- = accu2; + *pTmp_1-- = accu4; + } + + + fft(M, tmp, pDat_e); + + pTmp_0 = &tmp[2]; + pTmp_1 = &tmp[(M-1)*2]; + + for (i=1; i<M>>1; i++,pTmp_0+=2,pTmp_1-=2) { + + FIXP_DBL a1,a2; + FIXP_DBL accu3, accu4; + + a1 = ((pTmp_0[1]>>1) + (pTmp_1[1]>>1)); + a2 = ((pTmp_1[0]>>1) - (pTmp_0[0]>>1)); + + cplxMultDiv2(&accu1, &accu2, a2, a1, sin_twiddle_L64[(4*i)*inc]); + accu1<<=1; accu2<<=1; + + a1 = ((pTmp_0[0]>>1) + (pTmp_1[0]>>1)); + a2 = ((pTmp_0[1]>>1) - (pTmp_1[1]>>1)); + + cplxMultDiv2(&accu3, &accu4, (a1 + accu2), -(accu1 + a2), sin_twiddle_L64[i*inc]); + pDat[L - i] = accu4; + pDat[i] = accu3; + + cplxMultDiv2(&accu3, &accu4, (a1 - accu2), -(accu1 - a2), sin_twiddle_L64[(M-i)*inc]); + pDat[M + i] = accu4; + pDat[M - i] = accu3; + + } + + cplxMultDiv2(&accu1, &accu2, tmp[M], tmp[M+1], sin_twiddle_L64[(M/2)*inc]); + pDat[L - (M/2)] = accu2; + pDat[M/2] = accu1; + + pDat[0] = (tmp[0]>>1)+(tmp[1]>>1); + pDat[M] = fMult(((tmp[0]>>1)-(tmp[1]>>1)), sin_twiddle_L64[64/2].v.re);/* cos((PI/(2*L))*M); */ + + *pDat_e += 2; +} +#endif + +static +void getTables(const FIXP_WTP **twiddle, const FIXP_STP **sin_twiddle, int *sin_step, int length) +{ + int ld2_length; + + /* Get ld2 of length - 2 + 1 + -2: because first table entry is window of size 4 + +1: because we already include +1 because of ceil(log2(length)) */ + ld2_length = DFRACT_BITS-1-fNormz((FIXP_DBL)length) - 1; + + /* Extract sort of "eigenvalue" (the 4 left most bits) of length. */ + switch ( (length) >> (ld2_length-1) ) { + case 0x4: /* radix 2 */ + *sin_twiddle = SineTable512; + *sin_step = 1<<(9 - ld2_length); + *twiddle = windowSlopes[0][0][ld2_length-1]; + break; + case 0x7: /* 10 ms */ + *sin_twiddle = SineTable480; + *sin_step = 1<<(8 - ld2_length); + *twiddle = windowSlopes[0][1][ld2_length]; + break; + default: + *sin_twiddle = NULL; + *sin_step = 0; + *twiddle = NULL; + break; + } + + FDK_ASSERT(*twiddle != NULL); + + FDK_ASSERT(*sin_step > 0); + +} + +#if !defined(FUNCTION_dct_IV) + +void dct_IV(FIXP_DBL *pDat, + int L, + int *pDat_e) +{ + int sin_step = 0; + int M = L >> 1; + + const FIXP_WTP *twiddle; + const FIXP_STP *sin_twiddle; + + FDK_ASSERT(L >= 4); + + getTables(&twiddle, &sin_twiddle, &sin_step, L); + +#ifdef FUNCTION_dct_IV_func1 + if (M>=4 && (M&3) == 0) { + /* ARM926: 44 cycles for 2 iterations = 22 cycles/iteration */ + dct_IV_func1(M>>2, twiddle, &pDat[0], &pDat[L-1]); + } else +#endif /* FUNCTION_dct_IV_func1 */ + { + FIXP_DBL *RESTRICT pDat_0 = &pDat[0]; + FIXP_DBL *RESTRICT pDat_1 = &pDat[L - 2]; + register int i; + + /* 29 cycles on ARM926 */ + for (i = 0; i < M-1; i+=2,pDat_0+=2,pDat_1-=2) + { + register FIXP_DBL accu1,accu2,accu3,accu4; + + accu1 = pDat_1[1]; accu2 = pDat_0[0]; + accu3 = pDat_0[1]; accu4 = pDat_1[0]; + + cplxMultDiv2(&accu1, &accu2, accu1, accu2, twiddle[i]); + cplxMultDiv2(&accu3, &accu4, accu4, accu3, twiddle[i+1]); + + pDat_0[0] = accu2; pDat_0[1] = accu1; + pDat_1[0] = accu4; pDat_1[1] = -accu3; + } + if (M&1) + { + register FIXP_DBL accu1,accu2; + + accu1 = pDat_1[1]; accu2 = pDat_0[0]; + + cplxMultDiv2(&accu1, &accu2, accu1, accu2, twiddle[i]); + + pDat_0[0] = accu2; pDat_0[1] = accu1; + } + } + + fft(M, pDat, pDat_e); + +#ifdef FUNCTION_dct_IV_func2 + if (M>=4 && (M&3) == 0) { + /* ARM926: 42 cycles for 2 iterations = 21 cycles/iteration */ + dct_IV_func2(M>>2, sin_twiddle, &pDat[0], &pDat[L], sin_step); + } else +#endif /* FUNCTION_dct_IV_func2 */ + { + FIXP_DBL *RESTRICT pDat_0 = &pDat[0]; + FIXP_DBL *RESTRICT pDat_1 = &pDat[L - 2]; + register FIXP_DBL accu1,accu2,accu3,accu4; + int idx, i; + + /* Sin and Cos values are 0.0f and 1.0f */ + accu1 = pDat_1[0]; + accu2 = pDat_1[1]; + + pDat_1[1] = -(pDat_0[1]>>1); + pDat_0[0] = (pDat_0[0]>>1); + + + /* 28 cycles for ARM926 */ + for (idx = sin_step,i=1; i<(M+1)>>1; i++, idx+=sin_step) + { + FIXP_STP twd = sin_twiddle[idx]; + cplxMultDiv2(&accu3, &accu4, accu1, accu2, twd); + pDat_0[1] = accu3; + pDat_1[0] = accu4; + + pDat_0+=2; + pDat_1-=2; + + cplxMultDiv2(&accu3, &accu4, pDat_0[1], pDat_0[0], twd); + + accu1 = pDat_1[0]; + accu2 = pDat_1[1]; + + pDat_1[1] = -accu3; + pDat_0[0] = accu4; + } + + if ( (M&1) == 0 ) + { + /* Last Sin and Cos value pair are the same */ + accu1 = fMultDiv2(accu1, WTC(0x5a82799a)); + accu2 = fMultDiv2(accu2, WTC(0x5a82799a)); + + pDat_1[0] = accu1 + accu2; + pDat_0[1] = accu1 - accu2; + } + } + + /* Add twiddeling scale. */ + *pDat_e += 2; +} +#endif /* defined (FUNCTION_dct_IV) */ + +#if !defined(FUNCTION_dst_IV) +void dst_IV(FIXP_DBL *pDat, + int L, + int *pDat_e ) +{ + int sin_step = 0; + int M = L >> 1; + + const FIXP_WTP *twiddle; + const FIXP_STP *sin_twiddle; + +#ifdef DSTIV2_ENABLE + if (L == 2) { + const FIXP_STP tab = STCP(0x7641AF3D, 0x30FB9452); + FIXP_DBL tmp1, tmp2; + + cplxMultDiv2(&tmp2, &tmp1, pDat[0], pDat[1], tab); + + pDat[0] = tmp1; + pDat[1] = tmp2; + + *pDat_e += 1; + + return; + } +#else + FDK_ASSERT(L >= 4); +#endif + + getTables(&twiddle, &sin_twiddle, &sin_step, L); + +#ifdef FUNCTION_dst_IV_func1 + if ( (M>=4) && ((M&3) == 0) ) { + dst_IV_func1(M, twiddle, &pDat[0], &pDat[L]); + } else +#endif + { + FIXP_DBL *RESTRICT pDat_0 = &pDat[0]; + FIXP_DBL *RESTRICT pDat_1 = &pDat[L - 2]; + + register int i; + + /* 34 cycles on ARM926 */ + for (i = 0; i < M-1; i+=2,pDat_0+=2,pDat_1-=2) + { + register FIXP_DBL accu1,accu2,accu3,accu4; + + accu1 = pDat_1[1]; accu2 = -pDat_0[0]; + accu3 = pDat_0[1]; accu4 = -pDat_1[0]; + + cplxMultDiv2(&accu1, &accu2, accu1, accu2, twiddle[i]); + cplxMultDiv2(&accu3, &accu4, accu4, accu3, twiddle[i+1]); + + pDat_0[0] = accu2; pDat_0[1] = accu1; + pDat_1[0] = accu4; pDat_1[1] = -accu3; + } + if (M&1) + { + register FIXP_DBL accu1,accu2; + + accu1 = pDat_1[1]; accu2 = -pDat_0[0]; + + cplxMultDiv2(&accu1, &accu2, accu1, accu2, twiddle[i]); + + pDat_0[0] = accu2; pDat_0[1] = accu1; + } + } + + fft(M, pDat, pDat_e); + +#ifdef FUNCTION_dst_IV_func2 + if ( (M>=4) && ((M&3) == 0) ) { + dst_IV_func2(M>>2, sin_twiddle + sin_step, &pDat[0], &pDat[L - 1], sin_step); + } else +#endif /* FUNCTION_dst_IV_func2 */ + { + FIXP_DBL *RESTRICT pDat_0; + FIXP_DBL *RESTRICT pDat_1; + register FIXP_DBL accu1,accu2,accu3,accu4; + int idx, i; + + pDat_0 = &pDat[0]; + pDat_1 = &pDat[L - 2]; + + /* Sin and Cos values are 0.0f and 1.0f */ + accu1 = pDat_1[0]; + accu2 = pDat_1[1]; + + pDat_1[1] = -(pDat_0[0]>>1); + pDat_0[0] = (pDat_0[1]>>1); + + for (idx = sin_step,i=1; i<(M+1)>>1; i++, idx+=sin_step) + { + FIXP_STP twd = sin_twiddle[idx]; + + cplxMultDiv2(&accu3, &accu4, accu1, accu2, twd); + pDat_1[0] = -accu3; + pDat_0[1] = -accu4; + + pDat_0+=2; + pDat_1-=2; + + cplxMultDiv2(&accu3, &accu4, pDat_0[1], pDat_0[0], twd); + + accu1 = pDat_1[0]; + accu2 = pDat_1[1]; + + pDat_0[0] = accu3; + pDat_1[1] = -accu4; + } + + if ( (M&1) == 0 ) + { + /* Last Sin and Cos value pair are the same */ + accu1 = fMultDiv2(accu1, WTC(0x5a82799a)); + accu2 = fMultDiv2(accu2, WTC(0x5a82799a)); + + pDat_0[1] = - accu1 - accu2; + pDat_1[0] = accu2 - accu1; + } + } + + /* Add twiddeling scale. */ + *pDat_e += 2; +} +#endif /* !defined(FUNCTION_dst_IV) */ + + |