FS-8853 enable change of resolution of fast arc cos table
It is possible now to apply lower resolution to mapping of float-integer-float and decrease size of mapped file.
This commit is contained in:
parent
566cc41908
commit
da7be641ba
|
@ -20,41 +20,71 @@
|
||||||
|
|
||||||
#ifdef FASTMATH
|
#ifdef FASTMATH
|
||||||
|
|
||||||
#define SIGN_MASK (0x80000000)
|
|
||||||
#define DATA_MASK (0x07FFFFF8)
|
|
||||||
|
|
||||||
#define SIGN_UNPACK_MASK (0x01000000)
|
|
||||||
#define DATA_UNPACK_MASK (0x00FFFFFF)
|
|
||||||
|
|
||||||
#define VARIA_DATA_MASK (0x87FFFFF8)
|
|
||||||
#define CONST_DATA_MASK (0x38000000)
|
|
||||||
|
|
||||||
#define ACOS_TABLE_LENGTH (1 << 25)
|
|
||||||
#define ACOS_TABLE_FILENAME "/tmp/acos_table.dat"
|
|
||||||
|
|
||||||
typedef union {
|
typedef union {
|
||||||
uint32_t i;
|
uint32_t i;
|
||||||
float f;
|
float f;
|
||||||
} float_conv_t;
|
} float_conv_t;
|
||||||
|
|
||||||
#ifdef FAST_ACOSF_TESTING
|
/*
|
||||||
static float strip_float(float f);
|
* Manipulate these parameters to change
|
||||||
#endif
|
* mapping's resolution. The sine tone
|
||||||
|
* of 1600Hz is detected even with 20
|
||||||
|
* bits discarded in float integer representation
|
||||||
|
* with only slightly increased amount of false
|
||||||
|
* positives (keeping variance threshold on 0.0001).
|
||||||
|
* 12 bits seem to be good choice when there is
|
||||||
|
* a need to compute faster and/or decrease mapped file
|
||||||
|
* size on disk while keeping false positives low.
|
||||||
|
*/
|
||||||
|
#define ACOS_TABLE_CONST_EXPONENT (0x70)
|
||||||
|
#define ACOS_TABLE_CONST_EXPONENT_BITS (3)
|
||||||
|
#define ACOS_TABLE_DISCARDED_BITS (3)
|
||||||
|
/* rosolution:
|
||||||
|
3: 15 728 640 indices spreading range [0.0, 1.0], table size on disk 134 217 728 bytes (default)
|
||||||
|
4: 7 364 320 indices spreading range [0.0, 1.0], table size on disk 67 108 864 bytes
|
||||||
|
5: 3 932 160 indices spreading range [0.0, 1.0], table size on disk 33 554 432 bytes
|
||||||
|
12: 30 720 indices spreading range [0.0, 1.0], table size on disk 262 144 bytes
|
||||||
|
16: 1 920 indices spreading range [0.0, 1.0], table size on disk 16 384 bytes
|
||||||
|
20: 120 indices spreading range [0.0, 1.0], table size on disk 1 024 bytes
|
||||||
|
24: 7 indices spreading range [0.0, 1.0], table size on disk 64 bytes
|
||||||
|
26: 1 indices spreading range [0.0, 1.0], table size on disk 16 bytes
|
||||||
|
*/
|
||||||
|
#define ACOS_TABLE_FREE_EXPONENT_BITS (7 - ACOS_TABLE_CONST_EXPONENT_BITS)
|
||||||
|
#define ACOS_TABLE_DATA_BITS (31 - ACOS_TABLE_CONST_EXPONENT_BITS - ACOS_TABLE_DISCARDED_BITS)
|
||||||
|
#define ACOS_TABLE_LENGTH (1 << (31 - ACOS_TABLE_CONST_EXPONENT_BITS - ACOS_TABLE_DISCARDED_BITS))
|
||||||
|
|
||||||
|
#define VARIA_DATA_MASK (0x87FFFFFF & ~((1 << ACOS_TABLE_DISCARDED_BITS) - 1))
|
||||||
|
#define CONST_DATA_MASK (((1 << ACOS_TABLE_CONST_EXPONENT_BITS) - 1) \
|
||||||
|
<< (ACOS_TABLE_DATA_BITS - 1 + ACOS_TABLE_DISCARDED_BITS))
|
||||||
|
|
||||||
|
#define SIGN_UNPACK_MASK (1 << (ACOS_TABLE_DATA_BITS - 1))
|
||||||
|
#define DATA_UNPACK_MASK ((1 << (ACOS_TABLE_DATA_BITS - 1)) - 1)
|
||||||
|
|
||||||
|
#define SIGN_MASK (0x80000000)
|
||||||
|
#define DATA_MASK (DATA_UNPACK_MASK << ACOS_TABLE_DISCARDED_BITS)
|
||||||
|
|
||||||
|
#define ACOS_TABLE_FILENAME "/tmp/acos_table.dat"
|
||||||
|
|
||||||
static uint32_t index_from_float(float f);
|
static uint32_t index_from_float(float f);
|
||||||
static float float_from_index(uint32_t d);
|
static float float_from_index(uint32_t d);
|
||||||
static float *acos_table = NULL;
|
static float *acos_table = NULL;
|
||||||
static int acos_fd = -1;
|
static int acos_fd = -1;
|
||||||
|
|
||||||
|
|
||||||
#ifdef FAST_ACOSF_TESTING
|
#ifdef FAST_ACOSF_TESTING
|
||||||
static float strip_float(float f)
|
|
||||||
{
|
|
||||||
float_conv_t d;
|
|
||||||
|
|
||||||
d.i = d.i & (VARIA_DATA_MASK | CONST_DATA_MASK);
|
#define INF(x) printf("[%s] [%u]\n", #x, x)
|
||||||
|
#define INFX(x) printf("[%s] [%08x]\n", #x, x)
|
||||||
|
|
||||||
|
static void
|
||||||
|
debug_print(void);
|
||||||
|
|
||||||
|
static void
|
||||||
|
dump_table_summary(void);
|
||||||
|
|
||||||
|
#endif /* FAST_ACOSF_TESTING */
|
||||||
|
|
||||||
return d.i;
|
|
||||||
}
|
|
||||||
#endif
|
|
||||||
|
|
||||||
extern void compute_table(void)
|
extern void compute_table(void)
|
||||||
{
|
{
|
||||||
|
@ -114,23 +144,138 @@ extern float fast_acosf(float x)
|
||||||
return acos_table[index_from_float(x)];
|
return acos_table[index_from_float(x)];
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
||||||
static uint32_t index_from_float(float f)
|
static uint32_t index_from_float(float f)
|
||||||
{
|
{
|
||||||
float_conv_t d;
|
float_conv_t d;
|
||||||
|
|
||||||
d.f = f;
|
d.f = f;
|
||||||
return ((d.i & SIGN_MASK) >> 7) | ((d.i & DATA_MASK) >> 3);
|
return ((d.i & SIGN_MASK) >> (32 - ACOS_TABLE_DATA_BITS)) |
|
||||||
|
((d.i & DATA_MASK) >> ACOS_TABLE_DISCARDED_BITS);
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
||||||
static float float_from_index(uint32_t d)
|
static float float_from_index(uint32_t d)
|
||||||
{
|
{
|
||||||
float_conv_t f;
|
float_conv_t f;
|
||||||
|
f.i = ((d & SIGN_UNPACK_MASK) << (32 - ACOS_TABLE_DATA_BITS)) |
|
||||||
f.i = ((d & SIGN_UNPACK_MASK) << 7) | ((d & DATA_UNPACK_MASK) << 3) | CONST_DATA_MASK;
|
((d & DATA_UNPACK_MASK) << ACOS_TABLE_DISCARDED_BITS) | CONST_DATA_MASK;
|
||||||
return f.f;
|
return f.f;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
#ifdef FAST_ACOSF_TESTING
|
||||||
|
|
||||||
|
#define INF(x) printf("[%s] [%u]\n", #x, x)
|
||||||
|
#define INFX(x) printf("[%s] [%08x]\n", #x, x)
|
||||||
|
|
||||||
|
static void
|
||||||
|
debug_print(void)
|
||||||
|
{
|
||||||
|
INF(ACOS_TABLE_CONST_EXPONENT);
|
||||||
|
INF(ACOS_TABLE_CONST_EXPONENT_BITS);
|
||||||
|
INF(ACOS_TABLE_FREE_EXPONENT_BITS);
|
||||||
|
INF(ACOS_TABLE_DISCARDED_BITS);
|
||||||
|
INF(ACOS_TABLE_DATA_BITS);
|
||||||
|
INF(ACOS_TABLE_LENGTH);
|
||||||
|
INFX(VARIA_DATA_MASK);
|
||||||
|
INFX(CONST_DATA_MASK);
|
||||||
|
INFX(SIGN_UNPACK_MASK);
|
||||||
|
INFX(DATA_UNPACK_MASK);
|
||||||
|
INFX(SIGN_MASK);
|
||||||
|
INFX(DATA_MASK);
|
||||||
|
}
|
||||||
|
|
||||||
|
static void
|
||||||
|
dump_table_summary(void)
|
||||||
|
{
|
||||||
|
uint32_t i, i_0, i_1, di;
|
||||||
|
float f;
|
||||||
|
|
||||||
|
i = 1;
|
||||||
|
i_0 = index_from_float(0.0);
|
||||||
|
i_1 = index_from_float(1.0);
|
||||||
|
di = (i_1 - i_0)/100;
|
||||||
|
if (di == 0) di = 1;
|
||||||
|
|
||||||
|
for (; i < ACOS_TABLE_LENGTH; i += di )
|
||||||
|
{
|
||||||
|
f = float_from_index(i);
|
||||||
|
printf("-01i[%.10u] : ffi[%f] fa[%f] acos[%f]\n",
|
||||||
|
i, f, fast_acosf(f), acos(f));
|
||||||
|
}
|
||||||
|
|
||||||
|
i = 1;
|
||||||
|
for (; i < ACOS_TABLE_LENGTH; i = (i << 1))
|
||||||
|
{
|
||||||
|
f = fast_acosf(float_from_index(i));
|
||||||
|
printf("--i[%.10u] : fa[%f] ffi[%f]\n",
|
||||||
|
i, f, float_from_index(i));
|
||||||
|
}
|
||||||
|
|
||||||
|
f = 0.0;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.1;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.2;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.3;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.4;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.5;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.6;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.7;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 7.5;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.8;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.9;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.95;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.99;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 1.0;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 1.1;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 1.2;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = 0.0;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.1;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.2;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.3;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.4;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.5;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.6;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.7;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -7.5;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.8;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.9;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.95;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -0.99;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -1.0;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -1.1;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
f = -1.2;
|
||||||
|
printf("i [%d] from float [%f]\n", index_from_float(f), f);
|
||||||
|
}
|
||||||
|
|
||||||
|
#endif /* FAST_ACOSF_TESTING */
|
||||||
|
|
||||||
|
|
||||||
#endif
|
#endif
|
||||||
|
|
Loading…
Reference in New Issue