Merge PR #112: New converters: u16o12 and s16 #109

nb: regenerated starch files *not* committed yet, in the name of
minimizing merge conflicts for the moment.

convert.c

@@ -91,6 +91,54 @@ static void convert_sc16q11(void *iq_data,
  }
 }
 
+static void convert_s16(void *iq_data,
+ uint16_t *mag_data,
+ unsigned nsamples,
+ struct converter_state *state,
+ double *out_mean_level,
+ double *out_mean_power)
+{
+ MODES_NOTUSED(state);
+
+ const int16_t *in = (const int16_t *) iq_data;
+
+ if (STARCH_IS_ALIGNED(in) && STARCH_IS_ALIGNED(mag_data))
+ starch_magnitude_s16_aligned(in, mag_data, nsamples);
+ else
+ starch_magnitude_s16(in, mag_data, nsamples);
+
+ if (out_mean_level && out_mean_power) {
+ if (STARCH_IS_ALIGNED(mag_data))
+ starch_mean_power_u16_aligned(mag_data, nsamples, out_mean_level, out_mean_power);
+ else
+ starch_mean_power_u16(mag_data, nsamples, out_mean_level, out_mean_power);
+ }
+}
+
+static void convert_u16o12(void *iq_data,
+ uint16_t *mag_data,
+ unsigned nsamples,
+ struct converter_state *state,
+ double *out_mean_level,
+ double *out_mean_power)
+{
+ MODES_NOTUSED(state);
+
+ const uint16_t *in = (const uint16_t *) iq_data;
+
+ if (STARCH_IS_ALIGNED(in) && STARCH_IS_ALIGNED(mag_data))
+ starch_magnitude_u16o12_aligned(in, mag_data, nsamples);
+ else
+ starch_magnitude_u16o12(in, mag_data, nsamples);
+
+ if (out_mean_level && out_mean_power) {
+ if (STARCH_IS_ALIGNED(mag_data))
+ starch_mean_power_u16_aligned(mag_data, nsamples, out_mean_level, out_mean_power);
+ else
+ starch_mean_power_u16(mag_data, nsamples, out_mean_level, out_mean_power);
+ }
+}
+
 iq_convert_fn init_converter(input_format_t format,
  double sample_rate,
  int filter_dc,
@@ -111,6 +159,10 @@ iq_convert_fn init_converter(input_format_t format,
  return convert_sc16;
  case INPUT_SC16Q11:
  return convert_sc16q11;
+ case INPUT_S16:
+ return convert_s16;
+ case INPUT_U16O12:
+ return convert_u16o12;
  default:
  fprintf(stderr, "no suitable converter for format=%d\n", format);
  return NULL;

convert.h

@@ -21,7 +21,7 @@
 #define DUMP1090_CONVERT_H
 
 struct converter_state;
-typedef enum { INPUT_UC8=0, INPUT_SC16, INPUT_SC16Q11 } input_format_t;
+typedef enum { INPUT_UC8=0, INPUT_SC16, INPUT_SC16Q11, INPUT_S16, INPUT_U16O12 } input_format_t;
 
 typedef void (*iq_convert_fn)(void *iq_data,
  uint16_t *mag_data,

dsp/benchmark/magnitude_s16_benchmark.c

@@ -0,0 +1,42 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+
+
+void STARCH_BENCHMARK(magnitude_s16) (void)
+{
+ int16_t *in = NULL;
+ uint16_t *out_mag = NULL;
+ const unsigned len = 65535;
+
+ if (!(in = STARCH_BENCHMARK_ALLOC(len, int16_t)) || !(out_mag = STARCH_BENCHMARK_ALLOC(len, uint16_t))) {
+ goto done;
+ }
+
+ unsigned i = 0;
+
+ for (; i < len; ++i) {
+ in[i] = i - 32767;
+ out_mag[i] = abs(in[i]);
+ }
+
+ STARCH_BENCHMARK_RUN( magnitude_s16, in, out_mag, len );
+
+ done:
+ STARCH_BENCHMARK_FREE(in);
+ STARCH_BENCHMARK_FREE(out_mag);
+}
+
+bool STARCH_BENCHMARK_VERIFY(magnitude_s16) (const int16_t *in, uint16_t *out, unsigned len)
+{
+ bool okay = true;
+
+ for (unsigned i = 0; i < len; ++i) {
+ okay = (out[i] == abs(in[i]));
+ if (!okay) {
+ fprintf(stderr, "verification failed: in[%u]=%d out[%u]=%u\n", i, in[i], i, out[i]);
+ }
+ }
+
+ return okay;
+}

dsp/benchmark/magnitude_u16o12_benchmark.c

@@ -0,0 +1,48 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <math.h>
+
+void STARCH_BENCHMARK(magnitude_u16o12) (void)
+{
+ uint16_t *in = NULL;
+ uint16_t *out_mag = NULL;
+ const unsigned len = 4096;
+ unsigned i;
+
+ if (!(in = STARCH_BENCHMARK_ALLOC(len, uint16_t)) || !(out_mag = STARCH_BENCHMARK_ALLOC(len, uint16_t))) {
+ goto done;
+ }
+
+ for (i = 1; i < len; i++) {
+ in[i] = i;
+ }
+
+ STARCH_BENCHMARK_RUN( magnitude_u16o12, in, out_mag, len );
+
+ done:
+ STARCH_BENCHMARK_FREE(in);
+ STARCH_BENCHMARK_FREE(out_mag);
+}
+
+bool STARCH_BENCHMARK_VERIFY(magnitude_u16o12) (const uint16_t *in, uint16_t *out, unsigned len)
+{
+ bool okay = true;
+
+ for (unsigned i = 1; i < len; ++i) {
+ uint16_t j;
+ if (in[i] < 2048) {
+ j = 2048 - (out[i] * 2047.0 / 65535.0f - 0.5f);
+ } else {
+ j = 2048 + (out[i] * 2047.0 / 65535.0f + 0.5f);
+ }
+ okay = (j == in[j]);
+ if (!okay) {
+ fprintf(stderr, "verification failed: in[%u]=%d out[%u]=%u\n", i, in[i], i, out[i]);
+ }
+ }
+
+ return okay;
+}
+
+#undef CONVERT_AND_SCALE
+#undef MAGIC_SCALER

dsp/helpers/tables.c

@@ -103,3 +103,26 @@ const uint16_t * get_sc16q11_mag_12bit_table()
  return table;
 }
 
+#define CONVERT_AND_SCALE(__in) ceil(abs(le16toh(__in) - 2048) * (32767.0 / 2047.0))
+
+const uint16_t * get_u16o12_mag_table()
+{
+ static uint16_t *table = NULL;
+
+ if (table) {
+ return table;
+ }
+
+ table = malloc(sizeof(uint16_t) * 4096 * 4096);
+ if (!table) {
+ fprintf(stderr, "can't allocate u16to12 conversion lookup table\n");
+ abort();
+ }
+
+ table[0] = 65535;
+ for (int i = 1; i < 4096 ; i++) {
+ table[i] = CONVERT_AND_SCALE(i);
+ }
+
+ return table;
+}

dsp/helpers/tables.h

@@ -6,5 +6,6 @@
 const uint16_t * get_uc8_mag_table();
 const uint16_t * get_sc16q11_mag_11bit_table();
 const uint16_t * get_sc16q11_mag_12bit_table();
+const uint16_t * get_u16o12_mag_table();
 
 #endif

dsp/impl/magnitude_s16.c

@@ -0,0 +1,17 @@
+#include <math.h>
+#include <endian.h>
+
+/* Convert (little-endian) signed 16-bit values to unsigned 16-bit magnitudes */
+
+void STARCH_IMPL(magnitude_s16, exact_u32) (const int16_t *in, uint16_t *out, unsigned len)
+{
+ const int16_t * restrict in_align = STARCH_ALIGNED(in);
+ uint16_t * restrict out_align = STARCH_ALIGNED(out);
+
+ while (len--) {
+ out_align[0] = abs((int16_t) le16toh(in_align[0]));
+
+ out_align += 1;
+ in_align += 1;
+ }
+}