Speed up float converters a little, add a SC16Q11-nodc converter.

Mictronics · Jan 27, 2017 · b1a1771 · b1a1771
1 parent cde047a
commit b1a1771
Showing 1 changed file with 50 additions and 9 deletions.
diff --git a/convert.c b/convert.c
@@ -121,8 +121,8 @@ static void convert_uc8_generic(void *iq_data,
  for (i = 0; i < nsamples; ++i) {
  I = *in++;
  Q = *in++;
- fI = (I - 127.5) / 127.5;
- fQ = (Q - 127.5) / 127.5;
+ fI = (I - 127.5f) / 127.5f;
+ fQ = (Q - 127.5f) / 127.5f;
 
  // DC block
  z1_I = fI * dc_a + z1_I * dc_b;
@@ -137,7 +137,7 @@ static void convert_uc8_generic(void *iq_data,
  float mag = sqrtf(magsq);
  sum_power += magsq;
  sum_level += mag;
- *mag_data++ = (uint16_t)(mag * 65535.0 + 0.5);
+ *mag_data++ = (uint16_t)(mag * 65535.0f + 0.5f);
  }
 
  state->z1_I = z1_I;
@@ -173,8 +173,8 @@ static void convert_sc16_generic(void *iq_data,
  for (i = 0; i < nsamples; ++i) {
  I = (int16_t)le16toh(*in++);
  Q = (int16_t)le16toh(*in++);
- fI = I / 32768.0;
- fQ = Q / 32768.0;
+ fI = I / 32768.0f;
+ fQ = Q / 32768.0f;
 
  // DC block
  z1_I = fI * dc_a + z1_I * dc_b;
@@ -189,7 +189,7 @@ static void convert_sc16_generic(void *iq_data,
  float mag = sqrtf(magsq);
  sum_power += magsq;
  sum_level += mag;
- *mag_data++ = (uint16_t)(mag * 65535.0 + 0.5);
+ *mag_data++ = (uint16_t)(mag * 65535.0f + 0.5f);
  }
 
  state->z1_I = z1_I;
@@ -204,6 +204,46 @@ static void convert_sc16_generic(void *iq_data,
  }
 }
 
+static void convert_sc16q11_nodc(void *iq_data,
+ uint16_t *mag_data,
+ unsigned nsamples,
+ struct converter_state *state,
+ double *out_mean_level,
+ double *out_mean_power)
+{
+ uint16_t *in = iq_data;
+ unsigned i;
+ int16_t I, Q;
+ float fI, fQ, magsq;
+ float sum_level = 0, sum_power = 0;
+
+ MODES_NOTUSED(state);
+
+ for (i = 0; i < nsamples; ++i) {
+ I = (int16_t)le16toh(*in++);
+ Q = (int16_t)le16toh(*in++);
+ fI = I / 2048.0f;
+ fQ = Q / 2048.0f;
+
+ magsq = fI * fI + fQ * fQ;
+ if (magsq > 1)
+ magsq = 1;
+
+ float mag = sqrtf(magsq);
+ sum_power += magsq;
+ sum_level += mag;
+ *mag_data++ = (uint16_t)(mag * 65535.0f + 0.5f);
+ }
+
+ if (out_mean_level) {
+ *out_mean_level = sum_level / nsamples;
+ }
+
+ if (out_mean_power) {
+ *out_mean_power = sum_power / nsamples;
+ }
+}
+
 static void convert_sc16q11_generic(void *iq_data,
  uint16_t *mag_data,
  unsigned nsamples,
@@ -225,8 +265,8 @@ static void convert_sc16q11_generic(void *iq_data,
  for (i = 0; i < nsamples; ++i) {
  I = (int16_t)le16toh(*in++);
  Q = (int16_t)le16toh(*in++);
- fI = I / 2048.0;
- fQ = Q / 2048.0;
+ fI = I / 2048.0f;
+ fQ = Q / 2048.0f;
 
  // DC block
  z1_I = fI * dc_a + z1_I * dc_b;
@@ -241,7 +281,7 @@ static void convert_sc16q11_generic(void *iq_data,
  float mag = sqrtf(magsq);
  sum_power += magsq;
  sum_level += mag;
- *mag_data++ = (uint16_t)(sqrtf(magsq) * 65535.0 + 0.5);
+ *mag_data++ = (uint16_t)(mag * 65535.0f + 0.5f);
  }
 
  state->z1_I = z1_I;
@@ -266,6 +306,7 @@ static struct {
  { INPUT_UC8, 0, convert_uc8_nodc, "UC8, integer/table path" },
  { INPUT_UC8, 1, convert_uc8_generic, "UC8, float path" },
  { INPUT_SC16, 1, convert_sc16_generic, "SC16, float path" },
+ { INPUT_SC16Q11, 0, convert_sc16q11_nodc, "SC16Q11, float path, no DC block" },
  { INPUT_SC16Q11, 1, convert_sc16q11_generic, "SC16Q11, float path" },
  { 0, 0, NULL, NULL }
 };