Consolidate all fixed point math routines in one library (FS#10400) by Jeffrey Goode

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@21633 a1c6a512-1295-4272-9138-f99709370657
This commit is contained in:
Maurus Cuelenaere 2009-07-04 12:26:45 +00:00
parent 69c73e8bd6
commit 4710a32800
14 changed files with 773 additions and 713 deletions

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@ -125,6 +125,7 @@ recorder/recording.c
#if INPUT_SRC_CAPS != 0
audio_path.c
#endif /* INPUT_SRC_CAPS != 0 */
fixedpoint.c
pcmbuf.c
playback.c
codecs.c

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@ -21,6 +21,7 @@
#include "codeclib.h"
#include "inttypes.h"
#include "math.h"
#include "fixedpoint.h"
CODEC_HEADER
@ -41,124 +42,6 @@ const long cutoff = 500;
static int16_t samples[WAV_CHUNK_SIZE] IBSS_ATTR;
/* fixed point stuff from apps/plugins/lib/fixedpoint.c */
/* Inverse gain of circular cordic rotation in s0.31 format. */
static const long cordic_circular_gain = 0xb2458939; /* 0.607252929 */
/* Table of values of atan(2^-i) in 0.32 format fractions of pi where pi = 0xffffffff / 2 */
static const unsigned long atan_table[] = {
0x1fffffff, /* +0.785398163 (or pi/4) */
0x12e4051d, /* +0.463647609 */
0x09fb385b, /* +0.244978663 */
0x051111d4, /* +0.124354995 */
0x028b0d43, /* +0.062418810 */
0x0145d7e1, /* +0.031239833 */
0x00a2f61e, /* +0.015623729 */
0x00517c55, /* +0.007812341 */
0x0028be53, /* +0.003906230 */
0x00145f2e, /* +0.001953123 */
0x000a2f98, /* +0.000976562 */
0x000517cc, /* +0.000488281 */
0x00028be6, /* +0.000244141 */
0x000145f3, /* +0.000122070 */
0x0000a2f9, /* +0.000061035 */
0x0000517c, /* +0.000030518 */
0x000028be, /* +0.000015259 */
0x0000145f, /* +0.000007629 */
0x00000a2f, /* +0.000003815 */
0x00000517, /* +0.000001907 */
0x0000028b, /* +0.000000954 */
0x00000145, /* +0.000000477 */
0x000000a2, /* +0.000000238 */
0x00000051, /* +0.000000119 */
0x00000028, /* +0.000000060 */
0x00000014, /* +0.000000030 */
0x0000000a, /* +0.000000015 */
0x00000005, /* +0.000000007 */
0x00000002, /* +0.000000004 */
0x00000001, /* +0.000000002 */
0x00000000, /* +0.000000001 */
0x00000000, /* +0.000000000 */
};
/**
* Implements sin and cos using CORDIC rotation.
*
* @param phase has range from 0 to 0xffffffff, representing 0 and
* 2*pi respectively.
* @param cos return address for cos
* @return sin of phase, value is a signed value from LONG_MIN to LONG_MAX,
* representing -1 and 1 respectively.
*/
static long fsincos(unsigned long phase, long *cos)
{
int32_t x, x1, y, y1;
unsigned long z, z1;
int i;
/* Setup initial vector */
x = cordic_circular_gain;
y = 0;
z = phase;
/* The phase has to be somewhere between 0..pi for this to work right */
if (z < 0xffffffff / 4) {
/* z in first quadrant, z += pi/2 to correct */
x = -x;
z += 0xffffffff / 4;
} else if (z < 3 * (0xffffffff / 4)) {
/* z in third quadrant, z -= pi/2 to correct */
z -= 0xffffffff / 4;
} else {
/* z in fourth quadrant, z -= 3pi/2 to correct */
x = -x;
z -= 3 * (0xffffffff / 4);
}
/* Each iteration adds roughly 1-bit of extra precision */
for (i = 0; i < 31; i++) {
x1 = x >> i;
y1 = y >> i;
z1 = atan_table[i];
/* Decided which direction to rotate vector. Pivot point is pi/2 */
if (z >= 0xffffffff / 4) {
x -= y1;
y += x1;
z -= z1;
} else {
x += y1;
y -= x1;
z += z1;
}
}
if (cos)
*cos = x;
return y;
}
/**
* Fixed point square root via Newton-Raphson.
* @param a square root argument.
* @param fracbits specifies number of fractional bits in argument.
* @return Square root of argument in same fixed point format as input.
*/
static long fsqrt(long a, unsigned int fracbits)
{
long b = a/2 + (1 << fracbits); /* initial approximation */
unsigned n;
const unsigned iterations = 8; /* bumped up from 4 as it wasn't
nearly enough for 28 fractional bits */
for (n = 0; n < iterations; ++n)
b = (b + (long)(((long long)(a) << fracbits)/b))/2;
return b;
}
/* this is the codec entry point */
enum codec_status codec_main(void)
{

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@ -1,6 +1,6 @@
#if CONFIG_CODEC == SWCODEC /* software codec platforms */
codeclib.c
../../fixedpoint.c
mdct2.c
#ifdef CPU_ARM

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@ -0,0 +1,126 @@
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id: fixedpoint.h -1 $
*
* Copyright (C) 2006 Jens Arnold
*
* Fixed point library for plugins
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#ifndef _FIXEDPOINT_H
#define _FIXEDPOINT_H
#include <inttypes.h>
/** TAKEN FROM apps/dsp.h */
/* A bunch of fixed point assembler helper macros */
#if defined(CPU_COLDFIRE)
/* These macros use the Coldfire EMAC extension and need the MACSR flags set
* to fractional mode with no rounding.
*/
/* Multiply two S.31 fractional integers and return the sign bit and the
* 31 most significant bits of the result.
*/
#define FRACMUL(x, y) \
({ \
long t; \
asm ("mac.l %[a], %[b], %%acc0\n\t" \
"movclr.l %%acc0, %[t]\n\t" \
: [t] "=r" (t) : [a] "r" (x), [b] "r" (y)); \
t; \
})
/* Multiply two S.31 fractional integers, and return the 32 most significant
* bits after a shift left by the constant z. NOTE: Only works for shifts of
* 1 to 8 on Coldfire!
*/
#define FRACMUL_SHL(x, y, z) \
({ \
long t, t2; \
asm ("mac.l %[a], %[b], %%acc0\n\t" \
"moveq.l %[d], %[t]\n\t" \
"move.l %%accext01, %[t2]\n\t" \
"and.l %[mask], %[t2]\n\t" \
"lsr.l %[t], %[t2]\n\t" \
"movclr.l %%acc0, %[t]\n\t" \
"asl.l %[c], %[t]\n\t" \
"or.l %[t2], %[t]\n\t" \
: [t] "=&d" (t), [t2] "=&d" (t2) \
: [a] "r" (x), [b] "r" (y), [mask] "d" (0xff), \
[c] "i" ((z)), [d] "i" (8 - (z))); \
t; \
})
#elif defined(CPU_ARM)
/* Multiply two S.31 fractional integers and return the sign bit and the
* 31 most significant bits of the result.
*/
#define FRACMUL(x, y) \
({ \
long t, t2; \
asm ("smull %[t], %[t2], %[a], %[b]\n\t" \
"mov %[t2], %[t2], asl #1\n\t" \
"orr %[t], %[t2], %[t], lsr #31\n\t" \
: [t] "=&r" (t), [t2] "=&r" (t2) \
: [a] "r" (x), [b] "r" (y)); \
t; \
})
/* Multiply two S.31 fractional integers, and return the 32 most significant
* bits after a shift left by the constant z.
*/
#define FRACMUL_SHL(x, y, z) \
({ \
long t, t2; \
asm ("smull %[t], %[t2], %[a], %[b]\n\t" \
"mov %[t2], %[t2], asl %[c]\n\t" \
"orr %[t], %[t2], %[t], lsr %[d]\n\t" \
: [t] "=&r" (t), [t2] "=&r" (t2) \
: [a] "r" (x), [b] "r" (y), \
[c] "M" ((z) + 1), [d] "M" (31 - (z))); \
t; \
})
#else
#define FRACMUL(x, y) (long) (((((long long) (x)) * ((long long) (y))) >> 31))
#define FRACMUL_SHL(x, y, z) \
((long)(((((long long) (x)) * ((long long) (y))) >> (31 - (z)))))
#endif
#define DIV64(x, y, z) (long)(((long long)(x) << (z))/(y))
/** TAKEN FROM ORIGINAL fixedpoint.h */
/* fast unsigned multiplication (16x16bit->32bit or 32x32bit->32bit,
* whichever is faster for the architecture) */
#ifdef CPU_ARM
#define FMULU(a, b) ((uint32_t) (((uint32_t) (a)) * ((uint32_t) (b))))
#else /* SH1, coldfire */
#define FMULU(a, b) ((uint32_t) (((uint16_t) (a)) * ((uint16_t) (b))))
#endif
long fsincos(unsigned long phase, long *cos);
long fsqrt(long a, unsigned int fracbits);
long cos_int(int val);
long sin_int(int val);
long flog(int x);
#endif

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@ -26,6 +26,7 @@
/* DSP Based on Brad Martin's OpenSPC DSP emulator */
/* tag reading from sexyspc by John Brawn (John_Brawn@yahoo.com) and others */
#include "codeclib.h"
#include "fixedpoint.h"
#include "libspc/spc_codec.h"
#include "libspc/spc_profiler.h"

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@ -33,6 +33,7 @@
#include "misc.h"
#include "tdspeed.h"
#include "buffer.h"
#include "fixedpoint.h"
/* 16-bit samples are scaled based on these constants. The shift should be
* no more than 15.

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@ -64,86 +64,6 @@ enum {
DSP_CALLBACK_SET_STEREO_WIDTH
};
/* A bunch of fixed point assembler helper macros */
#if defined(CPU_COLDFIRE)
/* These macros use the Coldfire EMAC extension and need the MACSR flags set
* to fractional mode with no rounding.
*/
/* Multiply two S.31 fractional integers and return the sign bit and the
* 31 most significant bits of the result.
*/
#define FRACMUL(x, y) \
({ \
long t; \
asm ("mac.l %[a], %[b], %%acc0\n\t" \
"movclr.l %%acc0, %[t]\n\t" \
: [t] "=r" (t) : [a] "r" (x), [b] "r" (y)); \
t; \
})
/* Multiply two S.31 fractional integers, and return the 32 most significant
* bits after a shift left by the constant z. NOTE: Only works for shifts of
* 1 to 8 on Coldfire!
*/
#define FRACMUL_SHL(x, y, z) \
({ \
long t, t2; \
asm ("mac.l %[a], %[b], %%acc0\n\t" \
"moveq.l %[d], %[t]\n\t" \
"move.l %%accext01, %[t2]\n\t" \
"and.l %[mask], %[t2]\n\t" \
"lsr.l %[t], %[t2]\n\t" \
"movclr.l %%acc0, %[t]\n\t" \
"asl.l %[c], %[t]\n\t" \
"or.l %[t2], %[t]\n\t" \
: [t] "=&d" (t), [t2] "=&d" (t2) \
: [a] "r" (x), [b] "r" (y), [mask] "d" (0xff), \
[c] "i" ((z)), [d] "i" (8 - (z))); \
t; \
})
#elif defined(CPU_ARM)
/* Multiply two S.31 fractional integers and return the sign bit and the
* 31 most significant bits of the result.
*/
#define FRACMUL(x, y) \
({ \
long t, t2; \
asm ("smull %[t], %[t2], %[a], %[b]\n\t" \
"mov %[t2], %[t2], asl #1\n\t" \
"orr %[t], %[t2], %[t], lsr #31\n\t" \
: [t] "=&r" (t), [t2] "=&r" (t2) \
: [a] "r" (x), [b] "r" (y)); \
t; \
})
/* Multiply two S.31 fractional integers, and return the 32 most significant
* bits after a shift left by the constant z.
*/
#define FRACMUL_SHL(x, y, z) \
({ \
long t, t2; \
asm ("smull %[t], %[t2], %[a], %[b]\n\t" \
"mov %[t2], %[t2], asl %[c]\n\t" \
"orr %[t], %[t2], %[t], lsr %[d]\n\t" \
: [t] "=&r" (t), [t2] "=&r" (t2) \
: [a] "r" (x), [b] "r" (y), \
[c] "M" ((z) + 1), [d] "M" (31 - (z))); \
t; \
})
#else
#define FRACMUL(x, y) (long) (((((long long) (x)) * ((long long) (y))) >> 31))
#define FRACMUL_SHL(x, y, z) \
((long)(((((long long) (x)) * ((long long) (y))) >> (31 - (z)))))
#endif
#define DIV64(x, y, z) (long)(((long long)(x) << (z))/(y))
struct dsp_config;
int dsp_process(struct dsp_config *dsp, char *dest,

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@ -21,105 +21,10 @@
#include <inttypes.h>
#include "config.h"
#include "dsp.h"
#include "fixedpoint.h"
#include "eq.h"
#include "replaygain.h"
/* Inverse gain of circular cordic rotation in s0.31 format. */
static const long cordic_circular_gain = 0xb2458939; /* 0.607252929 */
/* Table of values of atan(2^-i) in 0.32 format fractions of pi where pi = 0xffffffff / 2 */
static const unsigned long atan_table[] = {
0x1fffffff, /* +0.785398163 (or pi/4) */
0x12e4051d, /* +0.463647609 */
0x09fb385b, /* +0.244978663 */
0x051111d4, /* +0.124354995 */
0x028b0d43, /* +0.062418810 */
0x0145d7e1, /* +0.031239833 */
0x00a2f61e, /* +0.015623729 */
0x00517c55, /* +0.007812341 */
0x0028be53, /* +0.003906230 */
0x00145f2e, /* +0.001953123 */
0x000a2f98, /* +0.000976562 */
0x000517cc, /* +0.000488281 */
0x00028be6, /* +0.000244141 */
0x000145f3, /* +0.000122070 */
0x0000a2f9, /* +0.000061035 */
0x0000517c, /* +0.000030518 */
0x000028be, /* +0.000015259 */
0x0000145f, /* +0.000007629 */
0x00000a2f, /* +0.000003815 */
0x00000517, /* +0.000001907 */
0x0000028b, /* +0.000000954 */
0x00000145, /* +0.000000477 */
0x000000a2, /* +0.000000238 */
0x00000051, /* +0.000000119 */
0x00000028, /* +0.000000060 */
0x00000014, /* +0.000000030 */
0x0000000a, /* +0.000000015 */
0x00000005, /* +0.000000007 */
0x00000002, /* +0.000000004 */
0x00000001, /* +0.000000002 */
0x00000000, /* +0.000000001 */
0x00000000, /* +0.000000000 */
};
/**
* Implements sin and cos using CORDIC rotation.
*
* @param phase has range from 0 to 0xffffffff, representing 0 and
* 2*pi respectively.
* @param cos return address for cos
* @return sin of phase, value is a signed value from LONG_MIN to LONG_MAX,
* representing -1 and 1 respectively.
*/
static long fsincos(unsigned long phase, long *cos) {
int32_t x, x1, y, y1;
unsigned long z, z1;
int i;
/* Setup initial vector */
x = cordic_circular_gain;
y = 0;
z = phase;
/* The phase has to be somewhere between 0..pi for this to work right */
if (z < 0xffffffff / 4) {
/* z in first quadrant, z += pi/2 to correct */
x = -x;
z += 0xffffffff / 4;
} else if (z < 3 * (0xffffffff / 4)) {
/* z in third quadrant, z -= pi/2 to correct */
z -= 0xffffffff / 4;
} else {
/* z in fourth quadrant, z -= 3pi/2 to correct */
x = -x;
z -= 3 * (0xffffffff / 4);
}
/* Each iteration adds roughly 1-bit of extra precision */
for (i = 0; i < 31; i++) {
x1 = x >> i;
y1 = y >> i;
z1 = atan_table[i];
/* Decided which direction to rotate vector. Pivot point is pi/2 */
if (z >= 0xffffffff / 4) {
x -= y1;
y += x1;
z -= z1;
} else {
x += y1;
y -= x1;
z += z1;
}
}
*cos = x;
return y;
}
/**
* Calculate first order shelving filter. Filter is not directly usable by the
* eq_filter() function.

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@ -23,6 +23,7 @@
#define _EQ_H
#include <inttypes.h>
#include <stdbool.h>
/* These depend on the fixed point formats used by the different filter types
and need to be changed when they change.

440
apps/fixedpoint.c Normal file
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@ -0,0 +1,440 @@
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id: fixedpoint.c -1 $
*
* Copyright (C) 2006 Jens Arnold
*
* Fixed point library for plugins
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include "fixedpoint.h"
#include <stdlib.h>
#include <stdbool.h>
#ifndef BIT_N
#define BIT_N(n) (1U << (n))
#endif
/** TAKEN FROM ORIGINAL fixedpoint.h */
/* Inverse gain of circular cordic rotation in s0.31 format. */
static const long cordic_circular_gain = 0xb2458939; /* 0.607252929 */
/* Table of values of atan(2^-i) in 0.32 format fractions of pi where pi = 0xffffffff / 2 */
static const unsigned long atan_table[] = {
0x1fffffff, /* +0.785398163 (or pi/4) */
0x12e4051d, /* +0.463647609 */
0x09fb385b, /* +0.244978663 */
0x051111d4, /* +0.124354995 */
0x028b0d43, /* +0.062418810 */
0x0145d7e1, /* +0.031239833 */
0x00a2f61e, /* +0.015623729 */
0x00517c55, /* +0.007812341 */
0x0028be53, /* +0.003906230 */
0x00145f2e, /* +0.001953123 */
0x000a2f98, /* +0.000976562 */
0x000517cc, /* +0.000488281 */
0x00028be6, /* +0.000244141 */
0x000145f3, /* +0.000122070 */
0x0000a2f9, /* +0.000061035 */
0x0000517c, /* +0.000030518 */
0x000028be, /* +0.000015259 */
0x0000145f, /* +0.000007629 */
0x00000a2f, /* +0.000003815 */
0x00000517, /* +0.000001907 */
0x0000028b, /* +0.000000954 */
0x00000145, /* +0.000000477 */
0x000000a2, /* +0.000000238 */
0x00000051, /* +0.000000119 */
0x00000028, /* +0.000000060 */
0x00000014, /* +0.000000030 */
0x0000000a, /* +0.000000015 */
0x00000005, /* +0.000000007 */
0x00000002, /* +0.000000004 */
0x00000001, /* +0.000000002 */
0x00000000, /* +0.000000001 */
0x00000000, /* +0.000000000 */
};
/* Precalculated sine and cosine * 16384 (2^14) (fixed point 18.14) */
static const short sin_table[91] =
{
0, 285, 571, 857, 1142, 1427, 1712, 1996, 2280, 2563,
2845, 3126, 3406, 3685, 3963, 4240, 4516, 4790, 5062, 5334,
5603, 5871, 6137, 6401, 6663, 6924, 7182, 7438, 7691, 7943,
8191, 8438, 8682, 8923, 9161, 9397, 9630, 9860, 10086, 10310,
10531, 10748, 10963, 11173, 11381, 11585, 11785, 11982, 12175, 12365,
12550, 12732, 12910, 13084, 13254, 13420, 13582, 13740, 13894, 14043,
14188, 14329, 14466, 14598, 14725, 14848, 14967, 15081, 15190, 15295,
15395, 15491, 15582, 15668, 15749, 15825, 15897, 15964, 16025, 16082,
16135, 16182, 16224, 16261, 16294, 16321, 16344, 16361, 16374, 16381,
16384
};
/**
* Implements sin and cos using CORDIC rotation.
*
* @param phase has range from 0 to 0xffffffff, representing 0 and
* 2*pi respectively.
* @param cos return address for cos
* @return sin of phase, value is a signed value from LONG_MIN to LONG_MAX,
* representing -1 and 1 respectively.
*/
long fsincos(unsigned long phase, long *cos)
{
int32_t x, x1, y, y1;
unsigned long z, z1;
int i;
/* Setup initial vector */
x = cordic_circular_gain;
y = 0;
z = phase;
/* The phase has to be somewhere between 0..pi for this to work right */
if (z < 0xffffffff / 4) {
/* z in first quadrant, z += pi/2 to correct */
x = -x;
z += 0xffffffff / 4;
} else if (z < 3 * (0xffffffff / 4)) {
/* z in third quadrant, z -= pi/2 to correct */
z -= 0xffffffff / 4;
} else {
/* z in fourth quadrant, z -= 3pi/2 to correct */
x = -x;
z -= 3 * (0xffffffff / 4);
}
/* Each iteration adds roughly 1-bit of extra precision */
for (i = 0; i < 31; i++) {
x1 = x >> i;
y1 = y >> i;
z1 = atan_table[i];
/* Decided which direction to rotate vector. Pivot point is pi/2 */
if (z >= 0xffffffff / 4) {
x -= y1;
y += x1;
z -= z1;
} else {
x += y1;
y -= x1;
z += z1;
}
}
if (cos)
*cos = x;
return y;
}
/**
* Fixed point square root via Newton-Raphson.
* @param x square root argument.
* @param fracbits specifies number of fractional bits in argument.
* @return Square root of argument in same fixed point format as input.
*
* This routine has been modified to run longer for greater precision,
* but cuts calculation short if the answer is reached sooner. In
* general, the closer x is to 1, the quicker the calculation.
*/
long fsqrt(long x, unsigned int fracbits)
{
long b = x/2 + BIT_N(fracbits); /* initial approximation */
long c;
unsigned n;
const unsigned iterations = 8;
for (n = 0; n < iterations; ++n)
{
c = DIV64(x, b, fracbits);
if (c == b) break;
b = (b + c)/2;
}
return b;
}
/**
* Fixed point sinus using a lookup table
* don't forget to divide the result by 16384 to get the actual sinus value
* @param val sinus argument in degree
* @return sin(val)*16384
*/
long sin_int(int val)
{
val = (val+360)%360;
if (val < 181)
{
if (val < 91)/* phase 0-90 degree */
return (long)sin_table[val];
else/* phase 91-180 degree */
return (long)sin_table[180-val];
}
else
{
if (val < 271)/* phase 181-270 degree */
return -(long)sin_table[val-180];
else/* phase 270-359 degree */
return -(long)sin_table[360-val];
}
return 0;
}
/**
* Fixed point cosinus using a lookup table
* don't forget to divide the result by 16384 to get the actual cosinus value
* @param val sinus argument in degree
* @return cos(val)*16384
*/
long cos_int(int val)
{
val = (val+360)%360;
if (val < 181)
{
if (val < 91)/* phase 0-90 degree */
return (long)sin_table[90-val];
else/* phase 91-180 degree */
return -(long)sin_table[val-90];
}
else
{
if (val < 271)/* phase 181-270 degree */
return -(long)sin_table[270-val];
else/* phase 270-359 degree */
return (long)sin_table[val-270];
}
return 0;
}
/**
* Fixed-point natural log
* taken from http://www.quinapalus.com/efunc.html
* "The code assumes integers are at least 32 bits long. The (positive)
* argument and the result of the function are both expressed as fixed-point
* values with 16 fractional bits, although intermediates are kept with 28
* bits of precision to avoid loss of accuracy during shifts."
*/
long flog(int x) {
long t,y;
y=0xa65af;
if(x<0x00008000) x<<=16, y-=0xb1721;
if(x<0x00800000) x<<= 8, y-=0x58b91;
if(x<0x08000000) x<<= 4, y-=0x2c5c8;
if(x<0x20000000) x<<= 2, y-=0x162e4;
if(x<0x40000000) x<<= 1, y-=0x0b172;
t=x+(x>>1); if((t&0x80000000)==0) x=t,y-=0x067cd;
t=x+(x>>2); if((t&0x80000000)==0) x=t,y-=0x03920;
t=x+(x>>3); if((t&0x80000000)==0) x=t,y-=0x01e27;
t=x+(x>>4); if((t&0x80000000)==0) x=t,y-=0x00f85;
t=x+(x>>5); if((t&0x80000000)==0) x=t,y-=0x007e1;
t=x+(x>>6); if((t&0x80000000)==0) x=t,y-=0x003f8;
t=x+(x>>7); if((t&0x80000000)==0) x=t,y-=0x001fe;
x=0x80000000-x;
y-=x>>15;
return y;
}
/** MODIFIED FROM replaygain.c */
/* These math routines have 64-bit internal precision to avoid overflows.
* Arguments and return values are 32-bit (long) precision.
*/
#define FP_MUL64(x, y) (((x) * (y)) >> (fracbits))
#define FP_DIV64(x, y) (((x) << (fracbits)) / (y))
static long long fp_exp10(long long x, unsigned int fracbits);
static long long fp_log10(long long n, unsigned int fracbits);
/* constants in fixed point format, 28 fractional bits */
#define FP28_LN2 (186065279LL) /* ln(2) */
#define FP28_LN2_INV (387270501LL) /* 1/ln(2) */
#define FP28_EXP_ZERO (44739243LL) /* 1/6 */
#define FP28_EXP_ONE (-745654LL) /* -1/360 */
#define FP28_EXP_TWO (12428LL) /* 1/21600 */
#define FP28_LN10 (618095479LL) /* ln(10) */
#define FP28_LOG10OF2 (80807124LL) /* log10(2) */
#define TOL_BITS 2 /* log calculation tolerance */
/* The fpexp10 fixed point math routine is based
* on oMathFP by Dan Carter (http://orbisstudios.com).
*/
/** FIXED POINT EXP10
* Return 10^x as FP integer. Argument is FP integer.
*/
static long long fp_exp10(long long x, unsigned int fracbits)
{
long long k;
long long z;
long long R;
long long xp;
/* scale constants */
const long long fp_one = (1 << fracbits);
const long long fp_half = (1 << (fracbits - 1));
const long long fp_two = (2 << fracbits);
const long long fp_mask = (fp_one - 1);
const long long fp_ln2_inv = (FP28_LN2_INV >> (28 - fracbits));
const long long fp_ln2 = (FP28_LN2 >> (28 - fracbits));
const long long fp_ln10 = (FP28_LN10 >> (28 - fracbits));
const long long fp_exp_zero = (FP28_EXP_ZERO >> (28 - fracbits));
const long long fp_exp_one = (FP28_EXP_ONE >> (28 - fracbits));
const long long fp_exp_two = (FP28_EXP_TWO >> (28 - fracbits));
/* exp(0) = 1 */
if (x == 0)
{
return fp_one;
}
/* convert from base 10 to base e */
x = FP_MUL64(x, fp_ln10);
/* calculate exp(x) */
k = (FP_MUL64(abs(x), fp_ln2_inv) + fp_half) & ~fp_mask;
if (x < 0)
{
k = -k;
}
x -= FP_MUL64(k, fp_ln2);
z = FP_MUL64(x, x);
R = fp_two + FP_MUL64(z, fp_exp_zero + FP_MUL64(z, fp_exp_one
+ FP_MUL64(z, fp_exp_two)));
xp = fp_one + FP_DIV64(FP_MUL64(fp_two, x), R - x);
if (k < 0)
{
k = fp_one >> (-k >> fracbits);
}
else
{
k = fp_one << (k >> fracbits);
}
return FP_MUL64(k, xp);
}
/** FIXED POINT LOG10
* Return log10(x) as FP integer. Argument is FP integer.
*/
static long long fp_log10(long long n, unsigned int fracbits)
{
/* Calculate log2 of argument */
long long log2, frac;
const long long fp_one = (1 << fracbits);
const long long fp_two = (2 << fracbits);
const long tolerance = (1 << ((fracbits / 2) + 2));
if (n <=0) return FP_NEGINF;
log2 = 0;
/* integer part */
while (n < fp_one)
{
log2 -= fp_one;
n <<= 1;
}
while (n >= fp_two)
{
log2 += fp_one;
n >>= 1;
}
/* fractional part */
frac = fp_one;
while (frac > tolerance)
{
frac >>= 1;
n = FP_MUL64(n, n);
if (n >= fp_two)
{
n >>= 1;
log2 += frac;
}
}
/* convert log2 to log10 */
return FP_MUL64(log2, (FP28_LOG10OF2 >> (28 - fracbits)));
}
/** CONVERT FACTOR TO DECIBELS */
long fp_decibels(unsigned long factor, unsigned int fracbits)
{
long long decibels;
long long f = (long long)factor;
bool neg;
/* keep factor in signed long range */
if (f >= (1LL << 31))
f = (1LL << 31) - 1;
/* decibels = 20 * log10(factor) */
decibels = FP_MUL64((20LL << fracbits), fp_log10(f, fracbits));
/* keep result in signed long range */
if ((neg = (decibels < 0)))
decibels = -decibels;
if (decibels >= (1LL << 31))
return neg ? FP_NEGINF : FP_INF;
return neg ? (long)-decibels : (long)decibels;
}
/** CONVERT DECIBELS TO FACTOR */
long fp_factor(long decibels, unsigned int fracbits)
{
bool neg;
long long factor;
long long db = (long long)decibels;
/* if decibels is 0, factor is 1 */
if (db == 0)
return (1L << fracbits);
/* calculate for positive decibels only */
if ((neg = (db < 0)))
db = -db;
/* factor = 10 ^ (decibels / 20) */
factor = fp_exp10(FP_DIV64(db, (20LL << fracbits)), fracbits);
/* keep result in signed long range, return 0 if very small */
if (factor >= (1LL << 31))
{
if (neg)
return 0;
else
return FP_INF;
}
/* if negative argument, factor is 1 / result */
if (neg)
factor = FP_DIV64((1LL << fracbits), factor);
return (long)factor;
}

197
apps/fixedpoint.h Normal file
View file

@ -0,0 +1,197 @@
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id: fixedpoint.h -1 $
*
* Copyright (C) 2006 Jens Arnold
*
* Fixed point library for plugins
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
/** FIXED POINT MATH ROUTINES - USAGE
*
* - x and y arguments are fixed point integers
* - fracbits is the number of fractional bits in the argument(s)
* - functions return long fixed point integers with the specified number
* of fractional bits unless otherwise specified
*
* Multiply two fixed point numbers:
* fp_mul(x, y, fracbits)
*
* Shortcut: Multiply two fixed point numbers with 31 fractional bits:
* fp31_mul(x, y)
*
* Shortcut: Multiply two fixed point numbers with 31 fractional bits,
* then shift left by z bits:
* fp31_mulshl(x, y, z)
* NOTE: z must be in the range 1-8 on Coldfire targets.
*
* Divide two fixed point numbers:
* fp_div(x, y, fracbits)
*
* Take square root of a fixed point number:
* fp_sqrt(x, fracbits)
*
* Calculate sin and cos of an angle:
* fp_sincos(phase, *cos)
* where phase is a 32 bit unsigned integer with 0 representing 0
* and 0xFFFFFFFF representing 2*pi, and *cos is the address to
* a long signed integer. Value returned is a long signed integer
* from LONG_MIN to LONG_MAX, representing -1 to 1 respectively.
* That is, value is a fixed point integer with 31 fractional bits.
*
* Calculate sin or cos of an angle (very fast, from a table):
* fp14_sin(angle)
* fp14_cos(angle)
* where angle is a non-fixed point integer in degrees. Value
* returned is a fixed point integer with 14 fractional bits.
*
* Calculate decibel equivalent of a gain factor:
* fp_decibels(factor, fracbits)
* where fracbits is in the range 12 to 22 (higher is better),
* and factor is a positive fixed point integer.
*
* Calculate factor equivalent of a decibel value:
* fp_factor(decibels, fracbits)
* where fracbits is in the range 12 to 22 (lower is better),
* and decibels is a fixed point integer.
*/
#ifndef _FIXEDPOINT_H
#define _FIXEDPOINT_H
#include <inttypes.h>
/* Redefine function names, making sure legacy code is usable */
#define fp31_mul(x, y) FRACMUL(x, y)
#define fp31_mulshl(x, y, z) FRACMUL_SHL(x, y, z)
#define fp_div(x, y, z) DIV64(x, y, z)
#define fp_sqrt(x, y) fsqrt(x, y)
#define fp_sincos(x, y) fsincos(x, y)
#define fp14_sin(x) sin_int(x)
#define fp14_cos(x) cos_int(x)
#define fp16_log(x) flog(x)
#define fp_mul(x, y, z) (long)((((long long)(x)) * ((long long)(y))) >> (z))
#define DIV64(x, y, z) (long)((((long long)(x)) << (z)) / ((long long)(y)))
/** TAKEN FROM apps/dsp.h */
/* A bunch of fixed point assembler helper macros */
#if defined(CPU_COLDFIRE)
/* These macros use the Coldfire EMAC extension and need the MACSR flags set
* to fractional mode with no rounding.
*/
/* Multiply two S.31 fractional integers and return the sign bit and the
* 31 most significant bits of the result.
*/
#define FRACMUL(x, y) \
({ \
long t; \
asm ("mac.l %[a], %[b], %%acc0\n\t" \
"movclr.l %%acc0, %[t]\n\t" \
: [t] "=r" (t) : [a] "r" (x), [b] "r" (y)); \
t; \
})
/* Multiply two S.31 fractional integers, and return the 32 most significant
* bits after a shift left by the constant z. NOTE: Only works for shifts of
* 1 to 8 on Coldfire!
*/
#define FRACMUL_SHL(x, y, z) \
({ \
long t, t2; \
asm ("mac.l %[a], %[b], %%acc0\n\t" \
"moveq.l %[d], %[t]\n\t" \
"move.l %%accext01, %[t2]\n\t" \
"and.l %[mask], %[t2]\n\t" \
"lsr.l %[t], %[t2]\n\t" \
"movclr.l %%acc0, %[t]\n\t" \
"asl.l %[c], %[t]\n\t" \
"or.l %[t2], %[t]\n\t" \
: [t] "=&d" (t), [t2] "=&d" (t2) \
: [a] "r" (x), [b] "r" (y), [mask] "d" (0xff), \
[c] "i" ((z)), [d] "i" (8 - (z))); \
t; \
})
#elif defined(CPU_ARM)
/* Multiply two S.31 fractional integers and return the sign bit and the
* 31 most significant bits of the result.
*/
#define FRACMUL(x, y) \
({ \
long t, t2; \
asm ("smull %[t], %[t2], %[a], %[b]\n\t" \
"mov %[t2], %[t2], asl #1\n\t" \
"orr %[t], %[t2], %[t], lsr #31\n\t" \
: [t] "=&r" (t), [t2] "=&r" (t2) \
: [a] "r" (x), [b] "r" (y)); \
t; \
})
/* Multiply two S.31 fractional integers, and return the 32 most significant
* bits after a shift left by the constant z.
*/
#define FRACMUL_SHL(x, y, z) \
({ \
long t, t2; \
asm ("smull %[t], %[t2], %[a], %[b]\n\t" \
"mov %[t2], %[t2], asl %[c]\n\t" \
"orr %[t], %[t2], %[t], lsr %[d]\n\t" \
: [t] "=&r" (t), [t2] "=&r" (t2) \
: [a] "r" (x), [b] "r" (y), \
[c] "M" ((z) + 1), [d] "M" (31 - (z))); \
t; \
})
#else
#define FRACMUL(x, y) (long) (((((long long) (x)) * ((long long) (y))) >> 31))
#define FRACMUL_SHL(x, y, z) \
((long)(((((long long) (x)) * ((long long) (y))) >> (31 - (z)))))
#endif
/** TAKEN FROM ORIGINAL fixedpoint.h */
/* fast unsigned multiplication (16x16bit->32bit or 32x32bit->32bit,
* whichever is faster for the architecture) */
#ifdef CPU_ARM
#define FMULU(a, b) ((uint32_t) (((uint32_t) (a)) * ((uint32_t) (b))))
#else /* SH1, coldfire */
#define FMULU(a, b) ((uint32_t) (((uint16_t) (a)) * ((uint16_t) (b))))
#endif
long fsincos(unsigned long phase, long *cos);
long fsqrt(long x, unsigned int fracbits);
long sin_int(int val);
long cos_int(int val);
long flog(int x);
/** MODIFIED FROM replaygain.c */
#define FP_INF (0x7fffffff)
#define FP_NEGINF -(0x7fffffff)
/* fracbits in range 12 - 22 work well. Higher is better for
* calculating dB, lower is better for calculating ratio.
*/
long fp_decibels(unsigned long factor, unsigned int fracbits);
long fp_factor(long decibels, unsigned int fracbits);
#endif

View file

@ -1,7 +1,7 @@
gcc-support.c
jhash.c
configfile.c
fixedpoint.c
../../fixedpoint.c
playback_control.c
rgb_hsv.c
buflib.c

View file

@ -1,238 +0,0 @@
/***************************************************************************
* __________ __ ___.
* Open \______ \ ____ ____ | | _\_ |__ _______ ___
* Source | _// _ \_/ ___\| |/ /| __ \ / _ \ \/ /
* Jukebox | | ( <_> ) \___| < | \_\ ( <_> > < <
* Firmware |____|_ /\____/ \___ >__|_ \|___ /\____/__/\_ \
* \/ \/ \/ \/ \/
* $Id$
*
* Copyright (C) 2006 Jens Arnold
*
* Fixed point library for plugins
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License
* as published by the Free Software Foundation; either version 2
* of the License, or (at your option) any later version.
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
* KIND, either express or implied.
*
****************************************************************************/
#include <inttypes.h>
#include "plugin.h"
#include "fixedpoint.h"
/* Inverse gain of circular cordic rotation in s0.31 format. */
static const long cordic_circular_gain = 0xb2458939; /* 0.607252929 */
/* Table of values of atan(2^-i) in 0.32 format fractions of pi where pi = 0xffffffff / 2 */
static const unsigned long atan_table[] = {
0x1fffffff, /* +0.785398163 (or pi/4) */
0x12e4051d, /* +0.463647609 */
0x09fb385b, /* +0.244978663 */
0x051111d4, /* +0.124354995 */
0x028b0d43, /* +0.062418810 */
0x0145d7e1, /* +0.031239833 */
0x00a2f61e, /* +0.015623729 */
0x00517c55, /* +0.007812341 */
0x0028be53, /* +0.003906230 */
0x00145f2e, /* +0.001953123 */
0x000a2f98, /* +0.000976562 */
0x000517cc, /* +0.000488281 */
0x00028be6, /* +0.000244141 */
0x000145f3, /* +0.000122070 */
0x0000a2f9, /* +0.000061035 */
0x0000517c, /* +0.000030518 */
0x000028be, /* +0.000015259 */
0x0000145f, /* +0.000007629 */
0x00000a2f, /* +0.000003815 */
0x00000517, /* +0.000001907 */
0x0000028b, /* +0.000000954 */
0x00000145, /* +0.000000477 */
0x000000a2, /* +0.000000238 */
0x00000051, /* +0.000000119 */
0x00000028, /* +0.000000060 */
0x00000014, /* +0.000000030 */
0x0000000a, /* +0.000000015 */
0x00000005, /* +0.000000007 */
0x00000002, /* +0.000000004 */
0x00000001, /* +0.000000002 */
0x00000000, /* +0.000000001 */
0x00000000, /* +0.000000000 */
};
/* Precalculated sine and cosine * 16384 (2^14) (fixed point 18.14) */
static const short sin_table[91] =
{
0, 285, 571, 857, 1142, 1427, 1712, 1996, 2280, 2563,
2845, 3126, 3406, 3685, 3963, 4240, 4516, 4790, 5062, 5334,
5603, 5871, 6137, 6401, 6663, 6924, 7182, 7438, 7691, 7943,
8191, 8438, 8682, 8923, 9161, 9397, 9630, 9860, 10086, 10310,
10531, 10748, 10963, 11173, 11381, 11585, 11785, 11982, 12175, 12365,
12550, 12732, 12910, 13084, 13254, 13420, 13582, 13740, 13894, 14043,
14188, 14329, 14466, 14598, 14725, 14848, 14967, 15081, 15190, 15295,
15395, 15491, 15582, 15668, 15749, 15825, 15897, 15964, 16025, 16082,
16135, 16182, 16224, 16261, 16294, 16321, 16344, 16361, 16374, 16381,
16384
};
/**
* Implements sin and cos using CORDIC rotation.
*
* @param phase has range from 0 to 0xffffffff, representing 0 and
* 2*pi respectively.
* @param cos return address for cos
* @return sin of phase, value is a signed value from LONG_MIN to LONG_MAX,
* representing -1 and 1 respectively.
*/
long fsincos(unsigned long phase, long *cos)
{
int32_t x, x1, y, y1;
unsigned long z, z1;
int i;
/* Setup initial vector */
x = cordic_circular_gain;
y = 0;
z = phase;
/* The phase has to be somewhere between 0..pi for this to work right */
if (z < 0xffffffff / 4) {
/* z in first quadrant, z += pi/2 to correct */
x = -x;
z += 0xffffffff / 4;
} else if (z < 3 * (0xffffffff / 4)) {
/* z in third quadrant, z -= pi/2 to correct */
z -= 0xffffffff / 4;
} else {
/* z in fourth quadrant, z -= 3pi/2 to correct */
x = -x;
z -= 3 * (0xffffffff / 4);
}
/* Each iteration adds roughly 1-bit of extra precision */
for (i = 0; i < 31; i++) {
x1 = x >> i;
y1 = y >> i;
z1 = atan_table[i];
/* Decided which direction to rotate vector. Pivot point is pi/2 */
if (z >= 0xffffffff / 4) {
x -= y1;
y += x1;
z -= z1;
} else {
x += y1;
y -= x1;
z += z1;
}
}
if (cos)
*cos = x;
return y;
}
/**
* Fixed point square root via Newton-Raphson.
* @param a square root argument.
* @param fracbits specifies number of fractional bits in argument.
* @return Square root of argument in same fixed point format as input.
*/
long fsqrt(long a, unsigned int fracbits)
{
long b = a/2 + BIT_N(fracbits); /* initial approximation */
unsigned n;
const unsigned iterations = 4;
for (n = 0; n < iterations; ++n)
b = (b + (long)(((long long)(a) << fracbits)/b))/2;
return b;
}
/**
* Fixed point sinus using a lookup table
* don't forget to divide the result by 16384 to get the actual sinus value
* @param val sinus argument in degree
* @return sin(val)*16384
*/
long sin_int(int val)
{
val = (val+360)%360;
if (val < 181)
{
if (val < 91)/* phase 0-90 degree */
return (long)sin_table[val];
else/* phase 91-180 degree */
return (long)sin_table[180-val];
}
else
{
if (val < 271)/* phase 181-270 degree */
return -(long)sin_table[val-180];
else/* phase 270-359 degree */
return -(long)sin_table[360-val];
}
return 0;
}
/**
* Fixed point cosinus using a lookup table
* don't forget to divide the result by 16384 to get the actual cosinus value
* @param val sinus argument in degree
* @return cos(val)*16384
*/
long cos_int(int val)
{
val = (val+360)%360;
if (val < 181)
{
if (val < 91)/* phase 0-90 degree */
return (long)sin_table[90-val];
else/* phase 91-180 degree */
return -(long)sin_table[val-90];
}
else
{
if (val < 271)/* phase 181-270 degree */
return -(long)sin_table[270-val];
else/* phase 270-359 degree */
return (long)sin_table[val-270];
}
return 0;
}
/**
* Fixed-point natural log
* taken from http://www.quinapalus.com/efunc.html
* "The code assumes integers are at least 32 bits long. The (positive)
* argument and the result of the function are both expressed as fixed-point
* values with 16 fractional bits, although intermediates are kept with 28
* bits of precision to avoid loss of accuracy during shifts."
*/
long flog(int x) {
long t,y;
y=0xa65af;
if(x<0x00008000) x<<=16, y-=0xb1721;
if(x<0x00800000) x<<= 8, y-=0x58b91;
if(x<0x08000000) x<<= 4, y-=0x2c5c8;
if(x<0x20000000) x<<= 2, y-=0x162e4;
if(x<0x40000000) x<<= 1, y-=0x0b172;
t=x+(x>>1); if((t&0x80000000)==0) x=t,y-=0x067cd;
t=x+(x>>2); if((t&0x80000000)==0) x=t,y-=0x03920;
t=x+(x>>3); if((t&0x80000000)==0) x=t,y-=0x01e27;
t=x+(x>>4); if((t&0x80000000)==0) x=t,y-=0x00f85;
t=x+(x>>5); if((t&0x80000000)==0) x=t,y-=0x007e1;
t=x+(x>>6); if((t&0x80000000)==0) x=t,y-=0x003f8;
t=x+(x>>7); if((t&0x80000000)==0) x=t,y-=0x001fe;
x=0x80000000-x;
y-=x>>15;
return y;
}

View file

@ -30,188 +30,11 @@
#include "metadata.h"
#include "debug.h"
#include "replaygain.h"
/* The fixed point math routines (with the exception of fp_atof) are based
* on oMathFP by Dan Carter (http://orbisstudios.com).
*/
/* 12 bits of precision gives fairly accurate result, but still allows a
* compact implementation. The math code supports up to 13...
*/
#include "fixedpoint.h"
#define FP_BITS (12)
#define FP_MASK ((1 << FP_BITS) - 1)
#define FP_ONE (1 << FP_BITS)
#define FP_TWO (2 << FP_BITS)
#define FP_HALF (1 << (FP_BITS - 1))
#define FP_LN2 ( 45426 >> (16 - FP_BITS))
#define FP_LN2_INV ( 94548 >> (16 - FP_BITS))
#define FP_EXP_ZERO ( 10922 >> (16 - FP_BITS))
#define FP_EXP_ONE ( -182 >> (16 - FP_BITS))
#define FP_EXP_TWO ( 4 >> (16 - FP_BITS))
#define FP_INF (0x7fffffff)
#define FP_LN10 (150902 >> (16 - FP_BITS))
#define FP_MAX_DIGITS (4)
#define FP_MAX_DIGITS_INT (10000)
#define FP_FAST_MUL_DIV
#ifdef FP_FAST_MUL_DIV
/* These macros can easily overflow, but they are good enough for our uses,
* and saves some code.
*/
#define fp_mul(x, y) (((x) * (y)) >> FP_BITS)
#define fp_div(x, y) (((x) << FP_BITS) / (y))
#else
static long fp_mul(long x, long y)
{
long x_neg = 0;
long y_neg = 0;
long rc;
if ((x == 0) || (y == 0))
{
return 0;
}
if (x < 0)
{
x_neg = 1;
x = -x;
}
if (y < 0)
{
y_neg = 1;
y = -y;
}
rc = (((x >> FP_BITS) * (y >> FP_BITS)) << FP_BITS)
+ (((x & FP_MASK) * (y & FP_MASK)) >> FP_BITS)
+ ((x & FP_MASK) * (y >> FP_BITS))
+ ((x >> FP_BITS) * (y & FP_MASK));
if ((x_neg ^ y_neg) == 1)
{
rc = -rc;
}
return rc;
}
static long fp_div(long x, long y)
{
long x_neg = 0;
long y_neg = 0;
long shifty;
long rc;
int msb = 0;
int lsb = 0;
if (x == 0)
{
return 0;
}
if (y == 0)
{
return (x < 0) ? -FP_INF : FP_INF;
}
if (x < 0)
{
x_neg = 1;
x = -x;
}
if (y < 0)
{
y_neg = 1;
y = -y;
}
while ((x & BIT_N(30 - msb)) == 0)
{
msb++;
}
while ((y & BIT_N(lsb)) == 0)
{
lsb++;
}
shifty = FP_BITS - (msb + lsb);
rc = ((x << msb) / (y >> lsb));
if (shifty > 0)
{
rc <<= shifty;
}
else
{
rc >>= -shifty;
}
if ((x_neg ^ y_neg) == 1)
{
rc = -rc;
}
return rc;
}
#endif /* FP_FAST_MUL_DIV */
static long fp_exp(long x)
{
long k;
long z;
long R;
long xp;
if (x == 0)
{
return FP_ONE;
}
k = (fp_mul(abs(x), FP_LN2_INV) + FP_HALF) & ~FP_MASK;
if (x < 0)
{
k = -k;
}
x -= fp_mul(k, FP_LN2);
z = fp_mul(x, x);
R = FP_TWO + fp_mul(z, FP_EXP_ZERO + fp_mul(z, FP_EXP_ONE
+ fp_mul(z, FP_EXP_TWO)));
xp = FP_ONE + fp_div(fp_mul(FP_TWO, x), R - x);
if (k < 0)
{
k = FP_ONE >> (-k >> FP_BITS);
}
else
{
k = FP_ONE << (k >> FP_BITS);
}
return fp_mul(k, xp);
}
static long fp_exp10(long x)
{
if (x == 0)
{
return FP_ONE;
}
return fp_exp(fp_mul(FP_LN10, x));
}
static long fp_atof(const char* s, int precision)
{
@ -300,7 +123,7 @@ static long convert_gain(long gain)
gain = 17 * FP_ONE;
}
gain = fp_exp10(gain / 20) << (24 - FP_BITS);
gain = fp_factor(gain, FP_BITS) << (24 - FP_BITS);
return gain;
}