#include "entcode.h"
#include "os_support.h"
-
-
-#ifndef OVERRIDE_FIND_MAX16
-static inline int find_max16(celt_word16 *x, int len)
-{
- celt_word16 max_corr=-VERY_LARGE16;
- int i, id = 0;
- for (i=0;i<len;i++)
- {
- if (x[i] > max_corr)
- {
- id = i;
- max_corr = x[i];
- }
- }
- return id;
-}
-#endif
-
-#ifndef OVERRIDE_FIND_MAX32
-static inline int find_max32(celt_word32 *x, int len)
-{
- celt_word32 max_corr=-VERY_LARGE32;
- int i, id = 0;
- for (i=0;i<len;i++)
- {
- if (x[i] > max_corr)
- {
- id = i;
- max_corr = x[i];
- }
- }
- return id;
-}
-#endif
-
/* Multiplies two 16-bit fractional values. Bit-exactness of this macro is important */
#define FRAC_MUL16(a,b) ((16384+((celt_int32)(celt_int16)(a)*(celt_int16)(b)))>>15)
-/* This is a cos() approximation designed to be bit-exact on any platform. Bit exactness
- with this approximation is important because it has an impact on the bit allocation */
-static inline celt_int16 bitexact_cos(celt_int16 x)
-{
- celt_int32 tmp;
- celt_int16 x2;
- tmp = (4096+((celt_int32)(x)*(x)))>>13;
- if (tmp > 32767)
- tmp = 32767;
- x2 = tmp;
- x2 = (32767-x2) + FRAC_MUL16(x2, (-7651 + FRAC_MUL16(x2, (8277 + FRAC_MUL16(-626, x2)))));
- if (x2 > 32766)
- x2 = 32766;
- return 1+x2;
-}
-
+unsigned isqrt32(celt_uint32 _val);
#ifndef FIXED_POINT
#define celt_sqrt(x) ((float)sqrt(x))
-#define celt_psqrt(x) ((float)sqrt(x))
#define celt_rsqrt(x) (1.f/celt_sqrt(x))
#define celt_rsqrt_norm(x) (celt_rsqrt(x))
#define celt_acos acos
#define celt_exp exp
-#define celt_cos_norm(x) (cos((.5f*M_PI)*(x)))
+#define celt_cos_norm(x) ((float)cos((.5f*M_PI)*(x)))
#define celt_atan atan
#define celt_rcp(x) (1.f/(x))
#define celt_div(a,b) ((a)/(b))
}
#else
-#define celt_log2(x) (1.442695040888963387*log(x))
-#define celt_exp2(x) (exp(0.6931471805599453094*(x)))
+#define celt_log2(x) ((float)(1.442695040888963387*log(x)))
+#define celt_exp2(x) ((float)exp(0.6931471805599453094*(x)))
#endif
#endif
return x <= 0 ? 0 : celt_ilog2(x);
}
-/** Reciprocal sqrt approximation in the range [0.25,1) (Q16 in, Q14 out) */
-static inline celt_word16 celt_rsqrt_norm(celt_word32 x)
-{
- celt_word16 n;
- celt_word16 r;
- celt_word16 r2;
- celt_word16 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))));
-}
+celt_word16 celt_rsqrt_norm(celt_word32 x);
-/** Reciprocal sqrt approximation (Q30 input, Q0 output or equivalent) */
-static inline celt_word32 celt_rsqrt(celt_word32 x)
-{
- int k;
- k = celt_ilog2(x)>>1;
- x = VSHR32(x, (k-7)<<1);
- return PSHR32(celt_rsqrt_norm(x), k);
-}
+celt_word32 celt_sqrt(celt_word32 x);
-/** Sqrt approximation (QX input, QX/2 output) */
-static inline celt_word32 celt_sqrt(celt_word32 x)
-{
- int k;
- celt_word16 n;
- celt_word32 rt;
- static const celt_word16 C[5] = {23175, 11561, -3011, 1699, -664};
- if (x==0)
- return 0;
- k = (celt_ilog2(x)>>1)-7;
- x = VSHR32(x, (k<<1));
- 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;
-}
-
-/** Sqrt approximation (QX input, QX/2 output) that assumes that the input is
- strictly positive */
-static inline celt_word32 celt_psqrt(celt_word32 x)
-{
- int k;
- celt_word16 n;
- celt_word32 rt;
- static const celt_word16 C[5] = {23175, 11561, -3011, 1699, -664};
- k = (celt_ilog2(x)>>1)-7;
- x = VSHR32(x, (k<<1));
- 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;
-}
+celt_word16 celt_cos_norm(celt_word32 x);
-#define L1 32767
-#define L2 -7651
-#define L3 8277
-#define L4 -626
-
-static inline celt_word16 _celt_cos_pi_2(celt_word16 x)
-{
- celt_word16 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
-
-static inline celt_word16 celt_cos_norm(celt_word32 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;
- }
-}
static inline celt_word16 celt_log2(celt_word32 x)
{
return VSHR32(EXTEND32(frac), -integer-2);
}
-/** Reciprocal approximation (Q15 input, Q16 output) */
-static inline celt_word32 celt_rcp(celt_word32 x)
-{
- int i;
- celt_word16 n;
- celt_word16 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);
-}
+celt_word32 celt_rcp(celt_word32 x);
#define celt_div(a,b) MULT32_32_Q31((celt_word32)(a),celt_rcp(b))
-static inline celt_word32 frac_div32(celt_word32 a, celt_word32 b)
-{
- celt_word16 rcp;
- celt_word32 result, rem;
- int shift = 30-celt_ilog2(b);
- a = SHL32(a,shift);
- b = SHL32(b,shift);
-
- /* 16-bit reciprocal */
- rcp = ROUND16(celt_rcp(ROUND16(b,16)),2);
- result = SHL32(MULT16_32_Q15(rcp, a),1);
- rem = a-MULT32_32_Q31(result, b);
- result += SHL32(MULT16_32_Q15(rcp, rem),1);
- return result;
-}
+celt_word32 frac_div32(celt_word32 a, celt_word32 b);
#define M1 32767
#define M2 -21
xiph / opus.git / blobdiff