--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/misc/libtremor/misc.h Sun Apr 24 22:57:57 2011 +0200
@@ -0,0 +1,244 @@
+/********************************************************************
+ * *
+ * THIS FILE IS PART OF THE OggVorbis 'TREMOR' CODEC SOURCE CODE. *
+ * *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
+ * *
+ * THE OggVorbis 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2002 *
+ * BY THE Xiph.Org FOUNDATION http://www.xiph.org/ *
+ * *
+ ********************************************************************
+
+ function: miscellaneous math and prototypes
+
+ ********************************************************************/
+
+#ifndef _V_RANDOM_H_
+#define _V_RANDOM_H_
+#include "ivorbiscodec.h"
+#include "os.h"
+
+#include "asm_arm.h"
+#include <stdlib.h> /* for abs() */
+
+#ifndef _V_WIDE_MATH
+#define _V_WIDE_MATH
+
+#ifndef _LOW_ACCURACY_
+/* 64 bit multiply */
+
+#if !(defined WIN32 && defined WINCE)
+#include <sys/types.h>
+#endif
+
+#if BYTE_ORDER==LITTLE_ENDIAN
+union magic {
+ struct {
+ ogg_int32_t lo;
+ ogg_int32_t hi;
+ } halves;
+ ogg_int64_t whole;
+};
+#endif
+
+#if BYTE_ORDER==BIG_ENDIAN
+union magic {
+ struct {
+ ogg_int32_t hi;
+ ogg_int32_t lo;
+ } halves;
+ ogg_int64_t whole;
+};
+#endif
+
+STIN ogg_int32_t MULT32(ogg_int32_t x, ogg_int32_t y) {
+ union magic magic;
+ magic.whole = (ogg_int64_t)x * y;
+ return magic.halves.hi;
+}
+
+STIN ogg_int32_t MULT31(ogg_int32_t x, ogg_int32_t y) {
+ return MULT32(x,y)<<1;
+}
+
+STIN ogg_int32_t MULT31_SHIFT15(ogg_int32_t x, ogg_int32_t y) {
+ union magic magic;
+ magic.whole = (ogg_int64_t)x * y;
+ return ((ogg_uint32_t)(magic.halves.lo)>>15) | ((magic.halves.hi)<<17);
+}
+
+#else
+/* 32 bit multiply, more portable but less accurate */
+
+/*
+ * Note: Precision is biased towards the first argument therefore ordering
+ * is important. Shift values were chosen for the best sound quality after
+ * many listening tests.
+ */
+
+/*
+ * For MULT32 and MULT31: The second argument is always a lookup table
+ * value already preshifted from 31 to 8 bits. We therefore take the
+ * opportunity to save on text space and use unsigned char for those
+ * tables in this case.
+ */
+
+STIN ogg_int32_t MULT32(ogg_int32_t x, ogg_int32_t y) {
+ return (x >> 9) * y; /* y preshifted >>23 */
+}
+
+STIN ogg_int32_t MULT31(ogg_int32_t x, ogg_int32_t y) {
+ return (x >> 8) * y; /* y preshifted >>23 */
+}
+
+STIN ogg_int32_t MULT31_SHIFT15(ogg_int32_t x, ogg_int32_t y) {
+ return (x >> 6) * y; /* y preshifted >>9 */
+}
+
+#endif
+
+/*
+ * This should be used as a memory barrier, forcing all cached values in
+ * registers to wr writen back to memory. Might or might not be beneficial
+ * depending on the architecture and compiler.
+ */
+#define MB()
+
+/*
+ * The XPROD functions are meant to optimize the cross products found all
+ * over the place in mdct.c by forcing memory operation ordering to avoid
+ * unnecessary register reloads as soon as memory is being written to.
+ * However this is only beneficial on CPUs with a sane number of general
+ * purpose registers which exclude the Intel x86. On Intel, better let the
+ * compiler actually reload registers directly from original memory by using
+ * macros.
+ */
+
+#ifdef __i386__
+
+#define XPROD32(_a, _b, _t, _v, _x, _y) \
+ { *(_x)=MULT32(_a,_t)+MULT32(_b,_v); \
+ *(_y)=MULT32(_b,_t)-MULT32(_a,_v); }
+#define XPROD31(_a, _b, _t, _v, _x, _y) \
+ { *(_x)=MULT31(_a,_t)+MULT31(_b,_v); \
+ *(_y)=MULT31(_b,_t)-MULT31(_a,_v); }
+#define XNPROD31(_a, _b, _t, _v, _x, _y) \
+ { *(_x)=MULT31(_a,_t)-MULT31(_b,_v); \
+ *(_y)=MULT31(_b,_t)+MULT31(_a,_v); }
+
+#else
+
+STIN void XPROD32(ogg_int32_t a, ogg_int32_t b,
+ ogg_int32_t t, ogg_int32_t v,
+ ogg_int32_t *x, ogg_int32_t *y)
+{
+ *x = MULT32(a, t) + MULT32(b, v);
+ *y = MULT32(b, t) - MULT32(a, v);
+}
+
+STIN void XPROD31(ogg_int32_t a, ogg_int32_t b,
+ ogg_int32_t t, ogg_int32_t v,
+ ogg_int32_t *x, ogg_int32_t *y)
+{
+ *x = MULT31(a, t) + MULT31(b, v);
+ *y = MULT31(b, t) - MULT31(a, v);
+}
+
+STIN void XNPROD31(ogg_int32_t a, ogg_int32_t b,
+ ogg_int32_t t, ogg_int32_t v,
+ ogg_int32_t *x, ogg_int32_t *y)
+{
+ *x = MULT31(a, t) - MULT31(b, v);
+ *y = MULT31(b, t) + MULT31(a, v);
+}
+
+#endif
+
+#endif
+
+#ifndef _V_CLIP_MATH
+#define _V_CLIP_MATH
+
+STIN ogg_int32_t CLIP_TO_15(ogg_int32_t x) {
+ int ret=x;
+ ret-= ((x<=32767)-1)&(x-32767);
+ ret-= ((x>=-32768)-1)&(x+32768);
+ return(ret);
+}
+
+#endif
+
+STIN ogg_int32_t VFLOAT_MULT(ogg_int32_t a,ogg_int32_t ap,
+ ogg_int32_t b,ogg_int32_t bp,
+ ogg_int32_t *p){
+ if(a && b){
+#ifndef _LOW_ACCURACY_
+ *p=ap+bp+32;
+ return MULT32(a,b);
+#else
+ *p=ap+bp+31;
+ return (a>>15)*(b>>16);
+#endif
+ }else
+ return 0;
+}
+
+int _ilog(unsigned int);
+
+STIN ogg_int32_t VFLOAT_MULTI(ogg_int32_t a,ogg_int32_t ap,
+ ogg_int32_t i,
+ ogg_int32_t *p){
+
+ int ip=_ilog(abs(i))-31;
+ return VFLOAT_MULT(a,ap,i<<-ip,ip,p);
+}
+
+STIN ogg_int32_t VFLOAT_ADD(ogg_int32_t a,ogg_int32_t ap,
+ ogg_int32_t b,ogg_int32_t bp,
+ ogg_int32_t *p){
+
+ if(!a){
+ *p=bp;
+ return b;
+ }else if(!b){
+ *p=ap;
+ return a;
+ }
+
+ /* yes, this can leak a bit. */
+ if(ap>bp){
+ int shift=ap-bp+1;
+ *p=ap+1;
+ a>>=1;
+ if(shift<32){
+ b=(b+(1<<(shift-1)))>>shift;
+ }else{
+ b=0;
+ }
+ }else{
+ int shift=bp-ap+1;
+ *p=bp+1;
+ b>>=1;
+ if(shift<32){
+ a=(a+(1<<(shift-1)))>>shift;
+ }else{
+ a=0;
+ }
+ }
+
+ a+=b;
+ if((a&0xc0000000)==0xc0000000 ||
+ (a&0xc0000000)==0){
+ a<<=1;
+ (*p)--;
+ }
+ return(a);
+}
+
+#endif
+
+
+
+