| Index: speex/libspeex/pseudofloat.h
|
| ===================================================================
|
| --- speex/libspeex/pseudofloat.h (revision 0)
|
| +++ speex/libspeex/pseudofloat.h (revision 0)
|
| @@ -0,0 +1,379 @@
|
| +/* Copyright (C) 2005 Jean-Marc Valin */
|
| +/**
|
| + @file pseudofloat.h
|
| + @brief Pseudo-floating point
|
| + * This header file provides a lightweight floating point type for
|
| + * use on fixed-point platforms when a large dynamic range is
|
| + * required. The new type is not compatible with the 32-bit IEEE format,
|
| + * it is not even remotely as accurate as 32-bit floats, and is not
|
| + * even guaranteed to produce even remotely correct results for code
|
| + * other than Speex. It makes all kinds of shortcuts that are acceptable
|
| + * for Speex, but may not be acceptable for your application. You're
|
| + * quite welcome to reuse this code and improve it, but don't assume
|
| + * it works out of the box. Most likely, it doesn't.
|
| + */
|
| +/*
|
| + 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.
|
| +
|
| + - Neither the name of the Xiph.org Foundation nor the names of its
|
| + contributors may be used to endorse or promote products derived from
|
| + this software without specific prior written permission.
|
| +
|
| + 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 FOUNDATION 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.
|
| +*/
|
| +
|
| +#ifndef PSEUDOFLOAT_H
|
| +#define PSEUDOFLOAT_H
|
| +
|
| +#include "arch.h"
|
| +#include "os_support.h"
|
| +#include "math_approx.h"
|
| +#include <math.h>
|
| +
|
| +#ifdef FIXED_POINT
|
| +
|
| +typedef struct {
|
| + spx_int16_t m;
|
| + spx_int16_t e;
|
| +} spx_float_t;
|
| +
|
| +static const spx_float_t FLOAT_ZERO = {0,0};
|
| +static const spx_float_t FLOAT_ONE = {16384,-14};
|
| +static const spx_float_t FLOAT_HALF = {16384,-15};
|
| +
|
| +#define MIN(a,b) ((a)<(b)?(a):(b))
|
| +static inline spx_float_t PSEUDOFLOAT(spx_int32_t x)
|
| +{
|
| + int e=0;
|
| + int sign=0;
|
| + if (x<0)
|
| + {
|
| + sign = 1;
|
| + x = -x;
|
| + }
|
| + if (x==0)
|
| + {
|
| + spx_float_t r = {0,0};
|
| + return r;
|
| + }
|
| + e = spx_ilog2(ABS32(x))-14;
|
| + x = VSHR32(x, e);
|
| + if (sign)
|
| + {
|
| + spx_float_t r;
|
| + r.m = -x;
|
| + r.e = e;
|
| + return r;
|
| + }
|
| + else
|
| + {
|
| + spx_float_t r;
|
| + r.m = x;
|
| + r.e = e;
|
| + return r;
|
| + }
|
| +}
|
| +
|
| +
|
| +static inline spx_float_t FLOAT_ADD(spx_float_t a, spx_float_t b)
|
| +{
|
| + spx_float_t r;
|
| + if (a.m==0)
|
| + return b;
|
| + else if (b.m==0)
|
| + return a;
|
| + if ((a).e > (b).e)
|
| + {
|
| + r.m = ((a).m>>1) + ((b).m>>MIN(15,(a).e-(b).e+1));
|
| + r.e = (a).e+1;
|
| + }
|
| + else
|
| + {
|
| + r.m = ((b).m>>1) + ((a).m>>MIN(15,(b).e-(a).e+1));
|
| + r.e = (b).e+1;
|
| + }
|
| + if (r.m>0)
|
| + {
|
| + if (r.m<16384)
|
| + {
|
| + r.m<<=1;
|
| + r.e-=1;
|
| + }
|
| + } else {
|
| + if (r.m>-16384)
|
| + {
|
| + r.m<<=1;
|
| + r.e-=1;
|
| + }
|
| + }
|
| + /*printf ("%f + %f = %f\n", REALFLOAT(a), REALFLOAT(b), REALFLOAT(r));*/
|
| + return r;
|
| +}
|
| +
|
| +static inline spx_float_t FLOAT_SUB(spx_float_t a, spx_float_t b)
|
| +{
|
| + spx_float_t r;
|
| + if (a.m==0)
|
| + return b;
|
| + else if (b.m==0)
|
| + return a;
|
| + if ((a).e > (b).e)
|
| + {
|
| + r.m = ((a).m>>1) - ((b).m>>MIN(15,(a).e-(b).e+1));
|
| + r.e = (a).e+1;
|
| + }
|
| + else
|
| + {
|
| + r.m = ((a).m>>MIN(15,(b).e-(a).e+1)) - ((b).m>>1);
|
| + r.e = (b).e+1;
|
| + }
|
| + if (r.m>0)
|
| + {
|
| + if (r.m<16384)
|
| + {
|
| + r.m<<=1;
|
| + r.e-=1;
|
| + }
|
| + } else {
|
| + if (r.m>-16384)
|
| + {
|
| + r.m<<=1;
|
| + r.e-=1;
|
| + }
|
| + }
|
| + /*printf ("%f + %f = %f\n", REALFLOAT(a), REALFLOAT(b), REALFLOAT(r));*/
|
| + return r;
|
| +}
|
| +
|
| +static inline int FLOAT_LT(spx_float_t a, spx_float_t b)
|
| +{
|
| + if (a.m==0)
|
| + return b.m>0;
|
| + else if (b.m==0)
|
| + return a.m<0;
|
| + if ((a).e > (b).e)
|
| + return ((a).m>>1) < ((b).m>>MIN(15,(a).e-(b).e+1));
|
| + else
|
| + return ((b).m>>1) > ((a).m>>MIN(15,(b).e-(a).e+1));
|
| +
|
| +}
|
| +
|
| +static inline int FLOAT_GT(spx_float_t a, spx_float_t b)
|
| +{
|
| + return FLOAT_LT(b,a);
|
| +}
|
| +
|
| +static inline spx_float_t FLOAT_MULT(spx_float_t a, spx_float_t b)
|
| +{
|
| + spx_float_t r;
|
| + r.m = (spx_int16_t)((spx_int32_t)(a).m*(b).m>>15);
|
| + r.e = (a).e+(b).e+15;
|
| + if (r.m>0)
|
| + {
|
| + if (r.m<16384)
|
| + {
|
| + r.m<<=1;
|
| + r.e-=1;
|
| + }
|
| + } else {
|
| + if (r.m>-16384)
|
| + {
|
| + r.m<<=1;
|
| + r.e-=1;
|
| + }
|
| + }
|
| + /*printf ("%f * %f = %f\n", REALFLOAT(a), REALFLOAT(b), REALFLOAT(r));*/
|
| + return r;
|
| +}
|
| +
|
| +static inline spx_float_t FLOAT_AMULT(spx_float_t a, spx_float_t b)
|
| +{
|
| + spx_float_t r;
|
| + r.m = (spx_int16_t)((spx_int32_t)(a).m*(b).m>>15);
|
| + r.e = (a).e+(b).e+15;
|
| + return r;
|
| +}
|
| +
|
| +
|
| +static inline spx_float_t FLOAT_SHL(spx_float_t a, int b)
|
| +{
|
| + spx_float_t r;
|
| + r.m = a.m;
|
| + r.e = a.e+b;
|
| + return r;
|
| +}
|
| +
|
| +static inline spx_int16_t FLOAT_EXTRACT16(spx_float_t a)
|
| +{
|
| + if (a.e<0)
|
| + return EXTRACT16((EXTEND32(a.m)+(EXTEND32(1)<<(-a.e-1)))>>-a.e);
|
| + else
|
| + return a.m<<a.e;
|
| +}
|
| +
|
| +static inline spx_int32_t FLOAT_EXTRACT32(spx_float_t a)
|
| +{
|
| + if (a.e<0)
|
| + return (EXTEND32(a.m)+(EXTEND32(1)<<(-a.e-1)))>>-a.e;
|
| + else
|
| + return EXTEND32(a.m)<<a.e;
|
| +}
|
| +
|
| +static inline spx_int32_t FLOAT_MUL32(spx_float_t a, spx_word32_t b)
|
| +{
|
| + return VSHR32(MULT16_32_Q15(a.m, b),-a.e-15);
|
| +}
|
| +
|
| +static inline spx_float_t FLOAT_MUL32U(spx_word32_t a, spx_word32_t b)
|
| +{
|
| + int e1, e2;
|
| + spx_float_t r;
|
| + if (a==0 || b==0)
|
| + {
|
| + return FLOAT_ZERO;
|
| + }
|
| + e1 = spx_ilog2(ABS32(a));
|
| + a = VSHR32(a, e1-14);
|
| + e2 = spx_ilog2(ABS32(b));
|
| + b = VSHR32(b, e2-14);
|
| + r.m = MULT16_16_Q15(a,b);
|
| + r.e = e1+e2-13;
|
| + return r;
|
| +}
|
| +
|
| +/* Do NOT attempt to divide by a negative number */
|
| +static inline spx_float_t FLOAT_DIV32_FLOAT(spx_word32_t a, spx_float_t b)
|
| +{
|
| + int e=0;
|
| + spx_float_t r;
|
| + if (a==0)
|
| + {
|
| + return FLOAT_ZERO;
|
| + }
|
| + e = spx_ilog2(ABS32(a))-spx_ilog2(b.m-1)-15;
|
| + a = VSHR32(a, e);
|
| + if (ABS32(a)>=SHL32(EXTEND32(b.m-1),15))
|
| + {
|
| + a >>= 1;
|
| + e++;
|
| + }
|
| + r.m = DIV32_16(a,b.m);
|
| + r.e = e-b.e;
|
| + return r;
|
| +}
|
| +
|
| +
|
| +/* Do NOT attempt to divide by a negative number */
|
| +static inline spx_float_t FLOAT_DIV32(spx_word32_t a, spx_word32_t b)
|
| +{
|
| + int e0=0,e=0;
|
| + spx_float_t r;
|
| + if (a==0)
|
| + {
|
| + return FLOAT_ZERO;
|
| + }
|
| + if (b>32767)
|
| + {
|
| + e0 = spx_ilog2(b)-14;
|
| + b = VSHR32(b, e0);
|
| + e0 = -e0;
|
| + }
|
| + e = spx_ilog2(ABS32(a))-spx_ilog2(b-1)-15;
|
| + a = VSHR32(a, e);
|
| + if (ABS32(a)>=SHL32(EXTEND32(b-1),15))
|
| + {
|
| + a >>= 1;
|
| + e++;
|
| + }
|
| + e += e0;
|
| + r.m = DIV32_16(a,b);
|
| + r.e = e;
|
| + return r;
|
| +}
|
| +
|
| +/* Do NOT attempt to divide by a negative number */
|
| +static inline spx_float_t FLOAT_DIVU(spx_float_t a, spx_float_t b)
|
| +{
|
| + int e=0;
|
| + spx_int32_t num;
|
| + spx_float_t r;
|
| + if (b.m<=0)
|
| + {
|
| + speex_warning_int("Attempted to divide by", b.m);
|
| + return FLOAT_ONE;
|
| + }
|
| + num = a.m;
|
| + a.m = ABS16(a.m);
|
| + while (a.m >= b.m)
|
| + {
|
| + e++;
|
| + a.m >>= 1;
|
| + }
|
| + num = num << (15-e);
|
| + r.m = DIV32_16(num,b.m);
|
| + r.e = a.e-b.e-15+e;
|
| + return r;
|
| +}
|
| +
|
| +static inline spx_float_t FLOAT_SQRT(spx_float_t a)
|
| +{
|
| + spx_float_t r;
|
| + spx_int32_t m;
|
| + m = SHL32(EXTEND32(a.m), 14);
|
| + r.e = a.e - 14;
|
| + if (r.e & 1)
|
| + {
|
| + r.e -= 1;
|
| + m <<= 1;
|
| + }
|
| + r.e >>= 1;
|
| + r.m = spx_sqrt(m);
|
| + return r;
|
| +}
|
| +
|
| +#else
|
| +
|
| +#define spx_float_t float
|
| +#define FLOAT_ZERO 0.f
|
| +#define FLOAT_ONE 1.f
|
| +#define FLOAT_HALF 0.5f
|
| +#define PSEUDOFLOAT(x) (x)
|
| +#define FLOAT_MULT(a,b) ((a)*(b))
|
| +#define FLOAT_AMULT(a,b) ((a)*(b))
|
| +#define FLOAT_MUL32(a,b) ((a)*(b))
|
| +#define FLOAT_DIV32(a,b) ((a)/(b))
|
| +#define FLOAT_EXTRACT16(a) (a)
|
| +#define FLOAT_EXTRACT32(a) (a)
|
| +#define FLOAT_ADD(a,b) ((a)+(b))
|
| +#define FLOAT_SUB(a,b) ((a)-(b))
|
| +#define REALFLOAT(x) (x)
|
| +#define FLOAT_DIV32_FLOAT(a,b) ((a)/(b))
|
| +#define FLOAT_MUL32U(a,b) ((a)*(b))
|
| +#define FLOAT_SHL(a,b) (a)
|
| +#define FLOAT_LT(a,b) ((a)<(b))
|
| +#define FLOAT_GT(a,b) ((a)>(b))
|
| +#define FLOAT_DIVU(a,b) ((a)/(b))
|
| +#define FLOAT_SQRT(a) (spx_sqrt(a))
|
| +
|
| +#endif
|
| +
|
| +#endif
|
|
|
| Property changes on: speex/libspeex/pseudofloat.h
|
| ___________________________________________________________________
|
| Name: svn:executable
|
| + *
|
|
|
|
|