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Revert dsp changes, need more research

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This commit is contained in:
DiSlord 2020-03-09 10:28:33 +03:00
parent a2d90a5e91
commit 5cf86ee1a6
1 changed files with 35 additions and 44 deletions
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79
dsp.c
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@ -41,57 +41,48 @@ const int16_t sincos_tbl[48][2] = {
{-24636, -21605 }, {-32698, -2143 }, {-27246, 18205 }, {-10533, 31029 } {-24636, -21605 }, {-32698, -2143 }, {-27246, 18205 }, {-10533, 31029 }
}; };
int64_t acc_samp_s; int32_t acc_samp_s;
int64_t acc_samp_c; int32_t acc_samp_c;
int64_t acc_ref_s; int32_t acc_ref_s;
int64_t acc_ref_c; int32_t acc_ref_c;
void void
dsp_process(int16_t *capture, size_t length) dsp_process(int16_t *capture, size_t length)
{ {
uint32_t *p = (uint32_t*)capture;
uint32_t len = length / 2;
uint32_t i; uint32_t i;
#if 1 int32_t samp_s = 0;
acc_samp_s = 0; int32_t samp_c = 0;
acc_samp_c = 0; int32_t ref_s = 0;
acc_ref_s = 0; int32_t ref_c = 0;
acc_ref_c = 0;
for (i = 0; i < length; i+=2) { for (i = 0; i < len; i++) {
int32_t ref = capture[i+0]; uint32_t sr = *p++;
int32_t smp = capture[i+1]; int16_t ref = sr & 0xffff;
int16_t smp = (sr>>16) & 0xffff;
#ifdef ENABLED_DUMP #ifdef ENABLED_DUMP
ref_buf[i] = ref; ref_buf[i] = ref;
samp_buf[i] = smp; samp_buf[i] = smp;
#endif #endif
int32_t s = ((int16_t *)sincos_tbl)[i+0]; int32_t s = sincos_tbl[i][0];
int32_t c = ((int16_t *)sincos_tbl)[i+1]; int32_t c = sincos_tbl[i][1];
acc_samp_s += (smp * s); samp_s += smp * s / 16;
acc_samp_c += (smp * c); samp_c += smp * c / 16;
acc_ref_s += (ref * s); ref_s += ref * s / 16;
acc_ref_c += (ref * c); ref_c += ref * c / 16;
} #if 0
#else uint32_t sc = *(uint32_t)&sincos_tbl[i];
uint32_t len = length / 2; samp_s = __SMLABB(sr, sc, samp_s);
int64_t samp_s = 0; samp_c = __SMLABT(sr, sc, samp_c);
int64_t samp_c = 0; ref_s = __SMLATB(sr, sc, ref_s);
int64_t ref_s = 0; ref_c = __SMLATT(sr, sc, ref_c);
int64_t ref_c = 0; #endif
// HI LO
int32_t *cos_sin = (int32_t *)sincos_tbl;
int32_t *ref_smp = (int32_t *)capture;
for (i = 0; i < len; i++) {
//
samp_s = __SMLALBB(*ref_smp, *cos_sin, samp_s); // samp_s+= smp * sin
samp_c = __SMLALBT(*ref_smp, *cos_sin, samp_c); // samp_c+= smp * cos
ref_s = __SMLALTB(*ref_smp, *cos_sin, ref_s); // ref_s += ref * sin
ref_c = __SMLALTT(*ref_smp, *cos_sin, ref_c); // ref_s += ref * cos
ref_smp++;
cos_sin++;
} }
acc_samp_s = samp_s; acc_samp_s = samp_s;
acc_samp_c = samp_c; acc_samp_c = samp_c;
acc_ref_s = ref_s; acc_ref_s = ref_s;
acc_ref_c = ref_c; acc_ref_c = ref_c;
#endif
} }
void void
@ -99,12 +90,12 @@ calculate_gamma(float gamma[2])
{ {
#if 1 #if 1
// calculate reflection coeff. by samp divide by ref // calculate reflection coeff. by samp divide by ref
double rs = acc_ref_s; float rs = acc_ref_s;
double rc = acc_ref_c; float rc = acc_ref_c;
double rr = rs * rs + rc * rc; float rr = rs * rs + rc * rc;
//rr = sqrtf(rr) * 1e8; //rr = sqrtf(rr) * 1e8;
double ss = acc_samp_s; float ss = acc_samp_s;
double sc = acc_samp_c; float sc = acc_samp_c;
gamma[0] = (sc * rc + ss * rs) / rr; gamma[0] = (sc * rc + ss * rs) / rr;
gamma[1] = (ss * rc - sc * rs) / rr; gamma[1] = (ss * rc - sc * rs) / rr;
#elif 0 #elif 0