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diff --git a/fdk-aac/libFDK/include/fixpoint_math.h b/fdk-aac/libFDK/include/fixpoint_math.h new file mode 100644 index 0000000..3805892 --- /dev/null +++ b/fdk-aac/libFDK/include/fixpoint_math.h @@ -0,0 +1,921 @@ +/* ----------------------------------------------------------------------------- +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. Gayer + + Description: Fixed point specific mathematical functions + +*******************************************************************************/ + +#ifndef FIXPOINT_MATH_H +#define FIXPOINT_MATH_H + +#include "common_fix.h" +#include "scale.h" + +/* + * Data definitions + */ + +#define LD_DATA_SCALING (64.0f) +#define LD_DATA_SHIFT 6 /* pow(2, LD_DATA_SHIFT) = LD_DATA_SCALING */ + +#define MAX_LD_PRECISION 10 +#define LD_PRECISION 10 + +/* Taylor series coefficients for ln(1-x), centered at 0 (MacLaurin polynomial). + */ +#ifndef LDCOEFF_16BIT +LNK_SECTION_CONSTDATA_L1 +static const FIXP_DBL ldCoeff[MAX_LD_PRECISION] = { + FL2FXCONST_DBL(-1.0), FL2FXCONST_DBL(-1.0 / 2.0), + FL2FXCONST_DBL(-1.0 / 3.0), FL2FXCONST_DBL(-1.0 / 4.0), + FL2FXCONST_DBL(-1.0 / 5.0), FL2FXCONST_DBL(-1.0 / 6.0), + FL2FXCONST_DBL(-1.0 / 7.0), FL2FXCONST_DBL(-1.0 / 8.0), + FL2FXCONST_DBL(-1.0 / 9.0), FL2FXCONST_DBL(-1.0 / 10.0)}; +#else /* LDCOEFF_16BIT */ +LNK_SECTION_CONSTDATA_L1 +static const FIXP_SGL ldCoeff[MAX_LD_PRECISION] = { + FL2FXCONST_SGL(-1.0), FL2FXCONST_SGL(-1.0 / 2.0), + FL2FXCONST_SGL(-1.0 / 3.0), FL2FXCONST_SGL(-1.0 / 4.0), + FL2FXCONST_SGL(-1.0 / 5.0), FL2FXCONST_SGL(-1.0 / 6.0), + FL2FXCONST_SGL(-1.0 / 7.0), FL2FXCONST_SGL(-1.0 / 8.0), + FL2FXCONST_SGL(-1.0 / 9.0), FL2FXCONST_SGL(-1.0 / 10.0)}; +#endif /* LDCOEFF_16BIT */ + +/***************************************************************************** + + functionname: invSqrtNorm2 + description: delivers 1/sqrt(op) normalized to .5...1 and the shift value +of the OUTPUT + +*****************************************************************************/ +#define SQRT_BITS 7 +#define SQRT_VALUES (128 + 2) +#define SQRT_BITS_MASK 0x7f +#define SQRT_FRACT_BITS_MASK 0x007FFFFF + +extern const FIXP_DBL invSqrtTab[SQRT_VALUES]; + +/* + * Hardware specific implementations + */ + +#if defined(__x86__) +#include "x86/fixpoint_math_x86.h" +#endif /* target architecture selector */ + +/* + * Fallback implementations + */ +#if !defined(FUNCTION_fIsLessThan) +/** + * \brief Compares two fixpoint values incl. scaling. + * \param a_m mantissa of the first input value. + * \param a_e exponent of the first input value. + * \param b_m mantissa of the second input value. + * \param b_e exponent of the second input value. + * \return non-zero if (a_m*2^a_e) < (b_m*2^b_e), 0 otherwise + */ +FDK_INLINE INT fIsLessThan(FIXP_DBL a_m, INT a_e, FIXP_DBL b_m, INT b_e) { + if (a_e > b_e) { + return ((b_m >> fMin(a_e - b_e, DFRACT_BITS - 1)) > a_m); + } else { + return ((a_m >> fMin(b_e - a_e, DFRACT_BITS - 1)) < b_m); + } +} + +FDK_INLINE INT fIsLessThan(FIXP_SGL a_m, INT a_e, FIXP_SGL b_m, INT b_e) { + if (a_e > b_e) { + return ((b_m >> fMin(a_e - b_e, FRACT_BITS - 1)) > a_m); + } else { + return ((a_m >> fMin(b_e - a_e, FRACT_BITS - 1)) < b_m); + } +} +#endif + +/** + * \brief deprecated. Use fLog2() instead. + */ +#define CalcLdData(op) fLog2(op, 0) + +void LdDataVector(FIXP_DBL *srcVector, FIXP_DBL *destVector, INT number); + +extern const UINT exp2_tab_long[32]; +extern const UINT exp2w_tab_long[32]; +extern const UINT exp2x_tab_long[32]; + +LNK_SECTION_CODE_L1 +FDK_INLINE FIXP_DBL CalcInvLdData(const FIXP_DBL x) { + int set_zero = (x < FL2FXCONST_DBL(-31.0 / 64.0)) ? 0 : 1; + int set_max = (x >= FL2FXCONST_DBL(31.0 / 64.0)) | (x == FL2FXCONST_DBL(0.0)); + + FIXP_SGL frac = (FIXP_SGL)((LONG)x & 0x3FF); + UINT index3 = (UINT)(LONG)(x >> 10) & 0x1F; + UINT index2 = (UINT)(LONG)(x >> 15) & 0x1F; + UINT index1 = (UINT)(LONG)(x >> 20) & 0x1F; + int exp = fMin(31, ((x > FL2FXCONST_DBL(0.0f)) ? (31 - (int)(x >> 25)) + : (int)(-(x >> 25)))); + + UINT lookup1 = exp2_tab_long[index1] * set_zero; + UINT lookup2 = exp2w_tab_long[index2]; + UINT lookup3 = exp2x_tab_long[index3]; + UINT lookup3f = + lookup3 + (UINT)(LONG)fMultDiv2((FIXP_DBL)(0x0016302F), (FIXP_SGL)frac); + + UINT lookup12 = (UINT)(LONG)fMult((FIXP_DBL)lookup1, (FIXP_DBL)lookup2); + UINT lookup = (UINT)(LONG)fMult((FIXP_DBL)lookup12, (FIXP_DBL)lookup3f); + + FIXP_DBL retVal = (lookup << 3) >> exp; + + if (set_max) { + retVal = (FIXP_DBL)MAXVAL_DBL; + } + + return retVal; +} + +void InitLdInt(); +FIXP_DBL CalcLdInt(INT i); + +extern const USHORT sqrt_tab[49]; + +inline FIXP_DBL sqrtFixp_lookup(FIXP_DBL x) { + UINT y = (INT)x; + UCHAR is_zero = (y == 0); + INT zeros = fixnormz_D(y) & 0x1e; + y <<= zeros; + UINT idx = (y >> 26) - 16; + USHORT frac = (y >> 10) & 0xffff; + USHORT nfrac = 0xffff ^ frac; + UINT t = (UINT)nfrac * sqrt_tab[idx] + (UINT)frac * sqrt_tab[idx + 1]; + t = t >> (zeros >> 1); + return (is_zero ? 0 : t); +} + +inline FIXP_DBL sqrtFixp_lookup(FIXP_DBL x, INT *x_e) { + UINT y = (INT)x; + INT e; + + if (x == (FIXP_DBL)0) { + return x; + } + + /* Normalize */ + e = fixnormz_D(y); + y <<= e; + e = *x_e - e + 2; + + /* Correct odd exponent. */ + if (e & 1) { + y >>= 1; + e++; + } + /* Get square root */ + UINT idx = (y >> 26) - 16; + USHORT frac = (y >> 10) & 0xffff; + USHORT nfrac = 0xffff ^ frac; + UINT t = (UINT)nfrac * sqrt_tab[idx] + (UINT)frac * sqrt_tab[idx + 1]; + + /* Write back exponent */ + *x_e = e >> 1; + return (FIXP_DBL)(LONG)(t >> 1); +} + +void InitInvSqrtTab(); + +#ifndef FUNCTION_invSqrtNorm2 +/** + * \brief calculate 1.0/sqrt(op) + * \param op_m mantissa of input value. + * \param result_e pointer to return the exponent of the result + * \return mantissa of the result + */ +/***************************************************************************** + delivers 1/sqrt(op) normalized to .5...1 and the shift value of the OUTPUT, + i.e. the denormalized result is 1/sqrt(op) = invSqrtNorm(op) * 2^(shift) + uses Newton-iteration for approximation + Q(n+1) = Q(n) + Q(n) * (0.5 - 2 * V * Q(n)^2) + with Q = 0.5* V ^-0.5; 0.5 <= V < 1.0 +*****************************************************************************/ +static FDK_FORCEINLINE FIXP_DBL invSqrtNorm2(FIXP_DBL op, INT *shift) { + FIXP_DBL val = op; + FIXP_DBL reg1, reg2; + + if (val == FL2FXCONST_DBL(0.0)) { + *shift = 16; + return ((LONG)MAXVAL_DBL); /* maximum positive value */ + } + +#define INVSQRTNORM2_LINEAR_INTERPOLATE +#define INVSQRTNORM2_LINEAR_INTERPOLATE_HQ + + /* normalize input, calculate shift value */ + FDK_ASSERT(val > FL2FXCONST_DBL(0.0)); + *shift = fNormz(val) - 1; /* CountLeadingBits() is not necessary here since + test value is always > 0 */ + val <<= *shift; /* normalized input V */ + *shift += 2; /* bias for exponent */ + +#if defined(INVSQRTNORM2_LINEAR_INTERPOLATE) + INT index = + (INT)(val >> (DFRACT_BITS - 1 - (SQRT_BITS + 1))) & SQRT_BITS_MASK; + FIXP_DBL Fract = + (FIXP_DBL)(((INT)val & SQRT_FRACT_BITS_MASK) << (SQRT_BITS + 1)); + FIXP_DBL diff = invSqrtTab[index + 1] - invSqrtTab[index]; + reg1 = invSqrtTab[index] + (fMultDiv2(diff, Fract) << 1); +#if defined(INVSQRTNORM2_LINEAR_INTERPOLATE_HQ) + /* reg1 = t[i] + (t[i+1]-t[i])*fract ... already computed ... + + (1-fract)fract*(t[i+2]-t[i+1])/2 */ + if (Fract != (FIXP_DBL)0) { + /* fract = fract * (1 - fract) */ + Fract = fMultDiv2(Fract, (FIXP_DBL)((ULONG)0x80000000 - (ULONG)Fract)) << 1; + diff = diff - (invSqrtTab[index + 2] - invSqrtTab[index + 1]); + reg1 = fMultAddDiv2(reg1, Fract, diff); + } +#endif /* INVSQRTNORM2_LINEAR_INTERPOLATE_HQ */ +#else +#error \ + "Either define INVSQRTNORM2_NEWTON_ITERATE or INVSQRTNORM2_LINEAR_INTERPOLATE" +#endif + /* calculate the output exponent = input exp/2 */ + if (*shift & 0x00000001) { /* odd shift values ? */ + /* Note: Do not use rounded value 0x5A82799A to avoid overflow with + * shift-by-2 */ + reg2 = (FIXP_DBL)0x5A827999; + /* FL2FXCONST_DBL(0.707106781186547524400844362104849f);*/ /* 1/sqrt(2); + */ + reg1 = fMultDiv2(reg1, reg2) << 2; + } + + *shift = *shift >> 1; + + return (reg1); +} +#endif /* FUNCTION_invSqrtNorm2 */ + +#ifndef FUNCTION_sqrtFixp +static FDK_FORCEINLINE FIXP_DBL sqrtFixp(FIXP_DBL op) { + INT tmp_exp = 0; + FIXP_DBL tmp_inv = invSqrtNorm2(op, &tmp_exp); + + FDK_ASSERT(tmp_exp > 0); + return ((FIXP_DBL)(fMultDiv2((op << (tmp_exp - 1)), tmp_inv) << 2)); +} +#endif /* FUNCTION_sqrtFixp */ + +#ifndef FUNCTION_invFixp +/** + * \brief calculate 1.0/op + * \param op mantissa of the input value. + * \return mantissa of the result with implicit exponent of 31 + * \exceptions are provided for op=0,1 setting max. positive value + */ +static inline FIXP_DBL invFixp(FIXP_DBL op) { + if ((op == (FIXP_DBL)0x00000000) || (op == (FIXP_DBL)0x00000001)) { + return ((LONG)MAXVAL_DBL); + } + INT tmp_exp; + FIXP_DBL tmp_inv = invSqrtNorm2(op, &tmp_exp); + FDK_ASSERT((31 - (2 * tmp_exp + 1)) >= 0); + int shift = 31 - (2 * tmp_exp + 1); + tmp_inv = fPow2Div2(tmp_inv); + if (shift) { + tmp_inv = ((tmp_inv >> (shift - 1)) + (FIXP_DBL)1) >> 1; + } + return tmp_inv; +} + +/** + * \brief calculate 1.0/(op_m * 2^op_e) + * \param op_m mantissa of the input value. + * \param op_e pointer into were the exponent of the input value is stored, and + * the result will be stored into. + * \return mantissa of the result + */ +static inline FIXP_DBL invFixp(FIXP_DBL op_m, int *op_e) { + if ((op_m == (FIXP_DBL)0x00000000) || (op_m == (FIXP_DBL)0x00000001)) { + *op_e = 31 - *op_e; + return ((LONG)MAXVAL_DBL); + } + + INT tmp_exp; + FIXP_DBL tmp_inv = invSqrtNorm2(op_m, &tmp_exp); + + *op_e = (tmp_exp << 1) - *op_e + 1; + return fPow2Div2(tmp_inv); +} +#endif /* FUNCTION_invFixp */ + +#ifndef FUNCTION_schur_div + +/** + * \brief Divide two FIXP_DBL values with given precision. + * \param num dividend + * \param denum divisor + * \param count amount of significant bits of the result (starting to the MSB) + * \return num/divisor + */ + +FIXP_DBL schur_div(FIXP_DBL num, FIXP_DBL denum, INT count); + +#endif /* FUNCTION_schur_div */ + +FIXP_DBL mul_dbl_sgl_rnd(const FIXP_DBL op1, const FIXP_SGL op2); + +#ifndef FUNCTION_fMultNorm +/** + * \brief multiply two values with normalization, thus max precision. + * Author: Robert Weidner + * + * \param f1 first factor + * \param f2 second factor + * \param result_e pointer to an INT where the exponent of the result is stored + * into + * \return mantissa of the product f1*f2 + */ +FIXP_DBL fMultNorm(FIXP_DBL f1, FIXP_DBL f2, INT *result_e); + +/** + * \brief Multiply 2 values using maximum precision. The exponent of the result + * is 0. + * \param f1_m mantissa of factor 1 + * \param f2_m mantissa of factor 2 + * \return mantissa of the result with exponent equal to 0 + */ +inline FIXP_DBL fMultNorm(FIXP_DBL f1, FIXP_DBL f2) { + FIXP_DBL m; + INT e; + + m = fMultNorm(f1, f2, &e); + + m = scaleValueSaturate(m, e); + + return m; +} + +/** + * \brief Multiply 2 values with exponent and use given exponent for the + * mantissa of the result. + * \param f1_m mantissa of factor 1 + * \param f1_e exponent of factor 1 + * \param f2_m mantissa of factor 2 + * \param f2_e exponent of factor 2 + * \param result_e exponent for the returned mantissa of the result + * \return mantissa of the result with exponent equal to result_e + */ +inline FIXP_DBL fMultNorm(FIXP_DBL f1_m, INT f1_e, FIXP_DBL f2_m, INT f2_e, + INT result_e) { + FIXP_DBL m; + INT e; + + m = fMultNorm(f1_m, f2_m, &e); + + m = scaleValueSaturate(m, e + f1_e + f2_e - result_e); + + return m; +} +#endif /* FUNCTION_fMultNorm */ + +#ifndef FUNCTION_fMultI +/** + * \brief Multiplies a fractional value and a integer value and performs + * rounding to nearest + * \param a fractional value + * \param b integer value + * \return integer value + */ +inline INT fMultI(FIXP_DBL a, INT b) { + FIXP_DBL m, mi; + INT m_e; + + m = fMultNorm(a, (FIXP_DBL)b, &m_e); + + if (m_e < (INT)0) { + if (m_e > (INT)-DFRACT_BITS) { + m = m >> ((-m_e) - 1); + mi = (m + (FIXP_DBL)1) >> 1; + } else { + mi = (FIXP_DBL)0; + } + } else { + mi = scaleValueSaturate(m, m_e); + } + + return ((INT)mi); +} +#endif /* FUNCTION_fMultI */ + +#ifndef FUNCTION_fMultIfloor +/** + * \brief Multiplies a fractional value and a integer value and performs floor + * rounding + * \param a fractional value + * \param b integer value + * \return integer value + */ +inline INT fMultIfloor(FIXP_DBL a, INT b) { + FIXP_DBL m, mi; + INT m_e; + + m = fMultNorm(a, (FIXP_DBL)b, &m_e); + + if (m_e < (INT)0) { + if (m_e > (INT)-DFRACT_BITS) { + mi = m >> (-m_e); + } else { + mi = (FIXP_DBL)0; + if (m < (FIXP_DBL)0) { + mi = (FIXP_DBL)-1; + } + } + } else { + mi = scaleValueSaturate(m, m_e); + } + + return ((INT)mi); +} +#endif /* FUNCTION_fMultIfloor */ + +#ifndef FUNCTION_fMultIceil +/** + * \brief Multiplies a fractional value and a integer value and performs ceil + * rounding + * \param a fractional value + * \param b integer value + * \return integer value + */ +inline INT fMultIceil(FIXP_DBL a, INT b) { + FIXP_DBL m, mi; + INT m_e; + + m = fMultNorm(a, (FIXP_DBL)b, &m_e); + + if (m_e < (INT)0) { + if (m_e > (INT)-DFRACT_BITS) { + mi = (m >> (-m_e)); + if ((LONG)m & ((1 << (-m_e)) - 1)) { + mi = mi + (FIXP_DBL)1; + } + } else { + mi = (FIXP_DBL)1; + if (m < (FIXP_DBL)0) { + mi = (FIXP_DBL)0; + } + } + } else { + mi = scaleValueSaturate(m, m_e); + } + + return ((INT)mi); +} +#endif /* FUNCTION_fMultIceil */ + +#ifndef FUNCTION_fDivNorm +/** + * \brief Divide 2 FIXP_DBL values with normalization of input values. + * \param num numerator + * \param denum denominator + * \param result_e pointer to an INT where the exponent of the result is stored + * into + * \return num/denum with exponent = *result_e + */ +FIXP_DBL fDivNorm(FIXP_DBL num, FIXP_DBL denom, INT *result_e); + +/** + * \brief Divide 2 positive FIXP_DBL values with normalization of input values. + * \param num numerator + * \param denum denominator + * \return num/denum with exponent = 0 + */ +FIXP_DBL fDivNorm(FIXP_DBL num, FIXP_DBL denom); + +/** + * \brief Divide 2 signed FIXP_DBL values with normalization of input values. + * \param num numerator + * \param denum denominator + * \param result_e pointer to an INT where the exponent of the result is stored + * into + * \return num/denum with exponent = *result_e + */ +FIXP_DBL fDivNormSigned(FIXP_DBL L_num, FIXP_DBL L_denum, INT *result_e); + +/** + * \brief Divide 2 signed FIXP_DBL values with normalization of input values. + * \param num numerator + * \param denum denominator + * \return num/denum with exponent = 0 + */ +FIXP_DBL fDivNormSigned(FIXP_DBL num, FIXP_DBL denom); +#endif /* FUNCTION_fDivNorm */ + +/** + * \brief Adjust mantissa to exponent -1 + * \param a_m mantissa of value to be adjusted + * \param pA_e pointer to the exponen of a_m + * \return adjusted mantissa + */ +inline FIXP_DBL fAdjust(FIXP_DBL a_m, INT *pA_e) { + INT shift; + + shift = fNorm(a_m) - 1; + *pA_e -= shift; + + return scaleValue(a_m, shift); +} + +#ifndef FUNCTION_fAddNorm +/** + * \brief Add two values with normalization + * \param a_m mantissa of first summand + * \param a_e exponent of first summand + * \param a_m mantissa of second summand + * \param a_e exponent of second summand + * \param pResult_e pointer to where the exponent of the result will be stored + * to. + * \return mantissa of result + */ +inline FIXP_DBL fAddNorm(FIXP_DBL a_m, INT a_e, FIXP_DBL b_m, INT b_e, + INT *pResult_e) { + INT result_e; + FIXP_DBL result_m; + + /* If one of the summands is zero, return the other. + This is necessary for the summation of a very small number to zero */ + if (a_m == (FIXP_DBL)0) { + *pResult_e = b_e; + return b_m; + } + if (b_m == (FIXP_DBL)0) { + *pResult_e = a_e; + return a_m; + } + + a_m = fAdjust(a_m, &a_e); + b_m = fAdjust(b_m, &b_e); + + if (a_e > b_e) { + result_m = a_m + (b_m >> fMin(a_e - b_e, DFRACT_BITS - 1)); + result_e = a_e; + } else { + result_m = (a_m >> fMin(b_e - a_e, DFRACT_BITS - 1)) + b_m; + result_e = b_e; + } + + *pResult_e = result_e; + return result_m; +} + +inline FIXP_DBL fAddNorm(FIXP_DBL a_m, INT a_e, FIXP_DBL b_m, INT b_e, + INT result_e) { + FIXP_DBL result_m; + + a_m = scaleValue(a_m, a_e - result_e); + b_m = scaleValue(b_m, b_e - result_e); + + result_m = a_m + b_m; + + return result_m; +} +#endif /* FUNCTION_fAddNorm */ + +/** + * \brief Divide 2 FIXP_DBL values with normalization of input values. + * \param num numerator + * \param denum denomintator + * \return num/denum with exponent = 0 + */ +FIXP_DBL fDivNormHighPrec(FIXP_DBL L_num, FIXP_DBL L_denum, INT *result_e); + +#ifndef FUNCTION_fPow +/** + * \brief return 2 ^ (exp_m * 2^exp_e) + * \param exp_m mantissa of the exponent to 2.0f + * \param exp_e exponent of the exponent to 2.0f + * \param result_e pointer to a INT where the exponent of the result will be + * stored into + * \return mantissa of the result + */ +FIXP_DBL f2Pow(const FIXP_DBL exp_m, const INT exp_e, INT *result_e); + +/** + * \brief return 2 ^ (exp_m * 2^exp_e). This version returns only the mantissa + * with implicit exponent of zero. + * \param exp_m mantissa of the exponent to 2.0f + * \param exp_e exponent of the exponent to 2.0f + * \return mantissa of the result + */ +FIXP_DBL f2Pow(const FIXP_DBL exp_m, const INT exp_e); + +/** + * \brief return x ^ (exp_m * 2^exp_e), where log2(x) = baseLd_m * 2^(baseLd_e). + * This saves the need to compute log2() of constant values (when x is a + * constant). + * \param baseLd_m mantissa of log2() of x. + * \param baseLd_e exponent of log2() of x. + * \param exp_m mantissa of the exponent to 2.0f + * \param exp_e exponent of the exponent to 2.0f + * \param result_e pointer to a INT where the exponent of the result will be + * stored into + * \return mantissa of the result + */ +FIXP_DBL fLdPow(FIXP_DBL baseLd_m, INT baseLd_e, FIXP_DBL exp_m, INT exp_e, + INT *result_e); + +/** + * \brief return x ^ (exp_m * 2^exp_e), where log2(x) = baseLd_m * 2^(baseLd_e). + * This saves the need to compute log2() of constant values (when x is a + * constant). This version does not return an exponent, which is + * implicitly 0. + * \param baseLd_m mantissa of log2() of x. + * \param baseLd_e exponent of log2() of x. + * \param exp_m mantissa of the exponent to 2.0f + * \param exp_e exponent of the exponent to 2.0f + * \return mantissa of the result + */ +FIXP_DBL fLdPow(FIXP_DBL baseLd_m, INT baseLd_e, FIXP_DBL exp_m, INT exp_e); + +/** + * \brief return (base_m * 2^base_e) ^ (exp * 2^exp_e). Use fLdPow() instead + * whenever possible. + * \param base_m mantissa of the base. + * \param base_e exponent of the base. + * \param exp_m mantissa of power to be calculated of the base. + * \param exp_e exponent of power to be calculated of the base. + * \param result_e pointer to a INT where the exponent of the result will be + * stored into. + * \return mantissa of the result. + */ +FIXP_DBL fPow(FIXP_DBL base_m, INT base_e, FIXP_DBL exp_m, INT exp_e, + INT *result_e); + +/** + * \brief return (base_m * 2^base_e) ^ N + * \param base_m mantissa of the base + * \param base_e exponent of the base + * \param N power to be calculated of the base + * \param result_e pointer to a INT where the exponent of the result will be + * stored into + * \return mantissa of the result + */ +FIXP_DBL fPowInt(FIXP_DBL base_m, INT base_e, INT N, INT *result_e); +#endif /* #ifndef FUNCTION_fPow */ + +#ifndef FUNCTION_fLog2 +/** + * \brief Calculate log(argument)/log(2) (logarithm with base 2). deprecated. + * Use fLog2() instead. + * \param arg mantissa of the argument + * \param arg_e exponent of the argument + * \param result_e pointer to an INT to store the exponent of the result + * \return the mantissa of the result. + * \param + */ +FIXP_DBL CalcLog2(FIXP_DBL arg, INT arg_e, INT *result_e); + +/** + * \brief calculate logarithm of base 2 of x_m * 2^(x_e) + * \param x_m mantissa of the input value. + * \param x_e exponent of the input value. + * \param pointer to an INT where the exponent of the result is returned into. + * \return mantissa of the result. + */ +FDK_INLINE FIXP_DBL fLog2(FIXP_DBL x_m, INT x_e, INT *result_e) { + FIXP_DBL result_m; + + /* Short cut for zero and negative numbers. */ + if (x_m <= FL2FXCONST_DBL(0.0f)) { + *result_e = DFRACT_BITS - 1; + return FL2FXCONST_DBL(-1.0f); + } + + /* Calculate log2() */ + { + FIXP_DBL x2_m; + + /* Move input value x_m * 2^x_e toward 1.0, where the taylor approximation + of the function log(1-x) centered at 0 is most accurate. */ + { + INT b_norm; + + b_norm = fNormz(x_m) - 1; + x2_m = x_m << b_norm; + x_e = x_e - b_norm; + } + + /* map x from log(x) domain to log(1-x) domain. */ + x2_m = -(x2_m + FL2FXCONST_DBL(-1.0)); + + /* Taylor polynomial approximation of ln(1-x) */ + { + FIXP_DBL px2_m; + result_m = FL2FXCONST_DBL(0.0); + px2_m = x2_m; + for (int i = 0; i < LD_PRECISION; i++) { + result_m = fMultAddDiv2(result_m, ldCoeff[i], px2_m); + px2_m = fMult(px2_m, x2_m); + } + } + /* Multiply result with 1/ln(2) = 1.0 + 0.442695040888 (get log2(x) from + * ln(x) result). */ + result_m = + fMultAddDiv2(result_m, result_m, + FL2FXCONST_DBL(2.0 * 0.4426950408889634073599246810019)); + + /* Add exponent part. log2(x_m * 2^x_e) = log2(x_m) + x_e */ + if (x_e != 0) { + int enorm; + + enorm = DFRACT_BITS - fNorm((FIXP_DBL)x_e); + /* The -1 in the right shift of result_m compensates the fMultDiv2() above + * in the taylor polynomial evaluation loop.*/ + result_m = (result_m >> (enorm - 1)) + + ((FIXP_DBL)x_e << (DFRACT_BITS - 1 - enorm)); + + *result_e = enorm; + } else { + /* 1 compensates the fMultDiv2() above in the taylor polynomial evaluation + * loop.*/ + *result_e = 1; + } + } + + return result_m; +} + +/** + * \brief calculate logarithm of base 2 of x_m * 2^(x_e) + * \param x_m mantissa of the input value. + * \param x_e exponent of the input value. + * \return mantissa of the result with implicit exponent of LD_DATA_SHIFT. + */ +FDK_INLINE FIXP_DBL fLog2(FIXP_DBL x_m, INT x_e) { + if (x_m <= FL2FXCONST_DBL(0.0f)) { + x_m = FL2FXCONST_DBL(-1.0f); + } else { + INT result_e; + x_m = fLog2(x_m, x_e, &result_e); + x_m = scaleValue(x_m, result_e - LD_DATA_SHIFT); + } + return x_m; +} + +#endif /* FUNCTION_fLog2 */ + +#ifndef FUNCTION_fAddSaturate +/** + * \brief Add with saturation of the result. + * \param a first summand + * \param b second summand + * \return saturated sum of a and b. + */ +inline FIXP_SGL fAddSaturate(const FIXP_SGL a, const FIXP_SGL b) { + LONG sum; + + sum = (LONG)(SHORT)a + (LONG)(SHORT)b; + sum = fMax(fMin((INT)sum, (INT)MAXVAL_SGL), (INT)MINVAL_SGL); + return (FIXP_SGL)(SHORT)sum; +} + +/** + * \brief Add with saturation of the result. + * \param a first summand + * \param b second summand + * \return saturated sum of a and b. + */ +inline FIXP_DBL fAddSaturate(const FIXP_DBL a, const FIXP_DBL b) { + LONG sum; + + sum = (LONG)(a >> 1) + (LONG)(b >> 1); + sum = fMax(fMin((INT)sum, (INT)(MAXVAL_DBL >> 1)), (INT)(MINVAL_DBL >> 1)); + return (FIXP_DBL)(LONG)(sum << 1); +} +#endif /* FUNCTION_fAddSaturate */ + +INT fixp_floorToInt(FIXP_DBL f_inp, INT sf); +FIXP_DBL fixp_floor(FIXP_DBL f_inp, INT sf); + +INT fixp_ceilToInt(FIXP_DBL f_inp, INT sf); +FIXP_DBL fixp_ceil(FIXP_DBL f_inp, INT sf); + +INT fixp_truncateToInt(FIXP_DBL f_inp, INT sf); +FIXP_DBL fixp_truncate(FIXP_DBL f_inp, INT sf); + +INT fixp_roundToInt(FIXP_DBL f_inp, INT sf); +FIXP_DBL fixp_round(FIXP_DBL f_inp, INT sf); + +/***************************************************************************** + + array for 1/n, n=1..80 + +****************************************************************************/ + +extern const FIXP_DBL invCount[80]; + +LNK_SECTION_INITCODE +inline void InitInvInt(void) {} + +/** + * \brief Calculate the value of 1/i where i is a integer value. It supports + * input values from 1 upto (80-1). + * \param intValue Integer input value. + * \param FIXP_DBL representation of 1/intValue + */ +inline FIXP_DBL GetInvInt(int intValue) { + return invCount[fMin(fMax(intValue, 0), 80 - 1)]; +} + +#endif /* FIXPOINT_MATH_H */ |