diff options
Diffstat (limited to 'src/main/jni/opus/celt/mathops.c')
-rw-r--r-- | src/main/jni/opus/celt/mathops.c | 208 |
1 files changed, 0 insertions, 208 deletions
diff --git a/src/main/jni/opus/celt/mathops.c b/src/main/jni/opus/celt/mathops.c deleted file mode 100644 index 3f8c5dcc0..000000000 --- a/src/main/jni/opus/celt/mathops.c +++ /dev/null @@ -1,208 +0,0 @@ -/* Copyright (c) 2002-2008 Jean-Marc Valin - Copyright (c) 2007-2008 CSIRO - Copyright (c) 2007-2009 Xiph.Org Foundation - Written by Jean-Marc Valin */ -/** - @file mathops.h - @brief Various math functions -*/ -/* - Redistribution and use in source and binary forms, with or without - modification, are permitted provided that the following conditions - are met: - - - Redistributions of source code must retain the above copyright - notice, this list of conditions and the following disclaimer. - - - Redistributions in binary form must reproduce the above copyright - notice, this list of conditions and the following disclaimer in the - documentation and/or other materials provided with the distribution. - - THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS - ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT - LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR - A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER - 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 OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS - SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. -*/ - -#ifdef HAVE_CONFIG_H -#include "config.h" -#endif - -#include "mathops.h" - -/*Compute floor(sqrt(_val)) with exact arithmetic. - This has been tested on all possible 32-bit inputs.*/ -unsigned isqrt32(opus_uint32 _val){ - unsigned b; - unsigned g; - int bshift; - /*Uses the second method from - http://www.azillionmonkeys.com/qed/sqroot.html - The main idea is to search for the largest binary digit b such that - (g+b)*(g+b) <= _val, and add it to the solution g.*/ - g=0; - bshift=(EC_ILOG(_val)-1)>>1; - b=1U<<bshift; - do{ - opus_uint32 t; - t=(((opus_uint32)g<<1)+b)<<bshift; - if(t<=_val){ - g+=b; - _val-=t; - } - b>>=1; - bshift--; - } - while(bshift>=0); - return g; -} - -#ifdef FIXED_POINT - -opus_val32 frac_div32(opus_val32 a, opus_val32 b) -{ - opus_val16 rcp; - opus_val32 result, rem; - int shift = celt_ilog2(b)-29; - a = VSHR32(a,shift); - b = VSHR32(b,shift); - /* 16-bit reciprocal */ - rcp = ROUND16(celt_rcp(ROUND16(b,16)),3); - result = MULT16_32_Q15(rcp, a); - rem = PSHR32(a,2)-MULT32_32_Q31(result, b); - result = ADD32(result, SHL32(MULT16_32_Q15(rcp, rem),2)); - if (result >= 536870912) /* 2^29 */ - return 2147483647; /* 2^31 - 1 */ - else if (result <= -536870912) /* -2^29 */ - return -2147483647; /* -2^31 */ - else - return SHL32(result, 2); -} - -/** Reciprocal sqrt approximation in the range [0.25,1) (Q16 in, Q14 out) */ -opus_val16 celt_rsqrt_norm(opus_val32 x) -{ - opus_val16 n; - opus_val16 r; - opus_val16 r2; - opus_val16 y; - /* Range of n is [-16384,32767] ([-0.5,1) in Q15). */ - n = x-32768; - /* Get a rough initial guess for the root. - The optimal minimax quadratic approximation (using relative error) is - r = 1.437799046117536+n*(-0.823394375837328+n*0.4096419668459485). - Coefficients here, and the final result r, are Q14.*/ - r = ADD16(23557, MULT16_16_Q15(n, ADD16(-13490, MULT16_16_Q15(n, 6713)))); - /* We want y = x*r*r-1 in Q15, but x is 32-bit Q16 and r is Q14. - We can compute the result from n and r using Q15 multiplies with some - adjustment, carefully done to avoid overflow. - Range of y is [-1564,1594]. */ - r2 = MULT16_16_Q15(r, r); - y = SHL16(SUB16(ADD16(MULT16_16_Q15(r2, n), r2), 16384), 1); - /* Apply a 2nd-order Householder iteration: r += r*y*(y*0.375-0.5). - This yields the Q14 reciprocal square root of the Q16 x, with a maximum - relative error of 1.04956E-4, a (relative) RMSE of 2.80979E-5, and a - peak absolute error of 2.26591/16384. */ - return ADD16(r, MULT16_16_Q15(r, MULT16_16_Q15(y, - SUB16(MULT16_16_Q15(y, 12288), 16384)))); -} - -/** Sqrt approximation (QX input, QX/2 output) */ -opus_val32 celt_sqrt(opus_val32 x) -{ - int k; - opus_val16 n; - opus_val32 rt; - static const opus_val16 C[5] = {23175, 11561, -3011, 1699, -664}; - if (x==0) - return 0; - else if (x>=1073741824) - return 32767; - k = (celt_ilog2(x)>>1)-7; - x = VSHR32(x, 2*k); - n = x-32768; - rt = ADD16(C[0], MULT16_16_Q15(n, ADD16(C[1], MULT16_16_Q15(n, ADD16(C[2], - MULT16_16_Q15(n, ADD16(C[3], MULT16_16_Q15(n, (C[4]))))))))); - rt = VSHR32(rt,7-k); - return rt; -} - -#define L1 32767 -#define L2 -7651 -#define L3 8277 -#define L4 -626 - -static OPUS_INLINE opus_val16 _celt_cos_pi_2(opus_val16 x) -{ - opus_val16 x2; - - x2 = MULT16_16_P15(x,x); - return ADD16(1,MIN16(32766,ADD32(SUB16(L1,x2), MULT16_16_P15(x2, ADD32(L2, MULT16_16_P15(x2, ADD32(L3, MULT16_16_P15(L4, x2 - )))))))); -} - -#undef L1 -#undef L2 -#undef L3 -#undef L4 - -opus_val16 celt_cos_norm(opus_val32 x) -{ - x = x&0x0001ffff; - if (x>SHL32(EXTEND32(1), 16)) - x = SUB32(SHL32(EXTEND32(1), 17),x); - if (x&0x00007fff) - { - if (x<SHL32(EXTEND32(1), 15)) - { - return _celt_cos_pi_2(EXTRACT16(x)); - } else { - return NEG32(_celt_cos_pi_2(EXTRACT16(65536-x))); - } - } else { - if (x&0x0000ffff) - return 0; - else if (x&0x0001ffff) - return -32767; - else - return 32767; - } -} - -/** Reciprocal approximation (Q15 input, Q16 output) */ -opus_val32 celt_rcp(opus_val32 x) -{ - int i; - opus_val16 n; - opus_val16 r; - celt_assert2(x>0, "celt_rcp() only defined for positive values"); - i = celt_ilog2(x); - /* n is Q15 with range [0,1). */ - n = VSHR32(x,i-15)-32768; - /* Start with a linear approximation: - r = 1.8823529411764706-0.9411764705882353*n. - The coefficients and the result are Q14 in the range [15420,30840].*/ - r = ADD16(30840, MULT16_16_Q15(-15420, n)); - /* Perform two Newton iterations: - r -= r*((r*n)-1.Q15) - = r*((r*n)+(r-1.Q15)). */ - r = SUB16(r, MULT16_16_Q15(r, - ADD16(MULT16_16_Q15(r, n), ADD16(r, -32768)))); - /* We subtract an extra 1 in the second iteration to avoid overflow; it also - neatly compensates for truncation error in the rest of the process. */ - r = SUB16(r, ADD16(1, MULT16_16_Q15(r, - ADD16(MULT16_16_Q15(r, n), ADD16(r, -32768))))); - /* r is now the Q15 solution to 2/(n+1), with a maximum relative error - of 7.05346E-5, a (relative) RMSE of 2.14418E-5, and a peak absolute - error of 1.24665/32768. */ - return VSHR32(EXTEND32(r),i-16); -} - -#endif |