Fix a mistake: count is the number of IQ samples

example/generate_iq_samples.c

@@ -2,7 +2,7 @@
 #include <stdint.h>
 #include <math.h>
 
-#define SAMPLE_COUNT 1536
+#define SAMPLE_COUNT 100
 
 int main(void) {
 	FILE *outfile;
@@ -11,16 +11,17 @@ int main(void) {
 	float time;
 
 	for(i = 0; i < SAMPLE_COUNT; i++) {
-		fflush(stdout);
 		time = (float) i / ((float) SAMPLE_COUNT);
-		samples[i * 2] = cos(6.28318530718 * time);
+		samples[i * 2] = cosf(6.28318530718 * time);
 		samples[i * 2 + 1] = 0.0;
-		printf("\rGenerating sample %lu: %f", i + 1, samples[i * 2]);
+
+		printf("\rGenerating sample for time %f: %f\n", time, samples[i * 2]);
+		fflush(stdout);
 	}
 
 	printf("\nWriting...\n");
 	outfile = fopen("pure_sine.bin", "w");
-	fwrite(samples, SAMPLE_COUNT * sizeof(float), 1, outfile);
+	fwrite(samples, SAMPLE_COUNT * 2 * sizeof(float), 1, outfile);
 	fclose(outfile);
 
 	return 0;

libtrx/trx_play.c

@@ -6,13 +6,13 @@
 
 #include "amarisoft/trx_driver.h"
 
-#define SAMPLE_RATE_KHZ 23040
-#define FLOAT_TO_CHAR_RATIO sizeof(float) / sizeof(char)
+#define SAMPLE_RATE_KHZ 30720
+#define COMPLEX_SIZE (sizeof(TRXComplex) / sizeof(char))
 #define I1E6 1000000
 #define I1E9 1000000000
 
 struct TRXPlayContext {
-	float *samples;
+	TRXComplex *samples;
 	uint64_t sample_count;
 	uint64_t current_sample;
 };
@@ -28,30 +28,32 @@ int trx_play_read(TRXState *s, trx_timestamp_t *ptimestamp, void **psamples, int
 	struct TRXPlayContext *trx_play_ctx;
 
 	uint64_t extra_samples;
-	float **channels;
+	uint64_t copy_samples;
+	TRXComplex **channels;
 
 	trx_play_ctx = s->opaque;
 
-	channels = (float **) psamples;
+	channels = (TRXComplex **) psamples;
 
 	// Handle reading after end of buffer
 	if(trx_play_ctx->current_sample + count >= trx_play_ctx->sample_count) {
 		extra_samples = trx_play_ctx->current_sample + count - trx_play_ctx->sample_count;
+		copy_samples = count - extra_samples;
 
-		memcpy(channels[0], trx_play_ctx->samples + trx_play_ctx->current_sample, (count - extra_samples) * sizeof(float));
-		memcpy(channels[1], trx_play_ctx->samples + trx_play_ctx->current_sample, (count - extra_samples) * sizeof(float));
+		memcpy(channels[0], trx_play_ctx->samples + trx_play_ctx->current_sample, copy_samples * sizeof(TRXComplex));
+		memcpy(channels[1], trx_play_ctx->samples + trx_play_ctx->current_sample, copy_samples * sizeof(TRXComplex));
 
 		if(extra_samples > 0) {
-			memcpy(channels[0], trx_play_ctx->samples, extra_samples * sizeof(float));
-			memcpy(channels[1], trx_play_ctx->samples, extra_samples * sizeof(float));
+			memcpy(channels[0] + copy_samples, trx_play_ctx->samples, extra_samples * sizeof(TRXComplex));
+			memcpy(channels[1] + copy_samples, trx_play_ctx->samples, extra_samples * sizeof(TRXComplex));
 		}
 
 		trx_play_ctx->current_sample = extra_samples;
 	} else {
-		memcpy(channels[0], trx_play_ctx->samples + trx_play_ctx->current_sample, count * sizeof(float));
-		memcpy(channels[1], trx_play_ctx->samples + trx_play_ctx->current_sample, count * sizeof(float));
+		memcpy(channels[0], trx_play_ctx->samples + trx_play_ctx->current_sample, count * sizeof(TRXComplex));
+		memcpy(channels[1], trx_play_ctx->samples + trx_play_ctx->current_sample, count * sizeof(TRXComplex));
 
-		//trx_play_ctx->current_sample += count;
+		trx_play_ctx->current_sample += count;
 	}
 
 	return count;
@@ -93,22 +95,22 @@ int trx_driver_init(TRXState *s) {
 
 	// Allocate the right size
 	fseek(samples_file_handle, 0, SEEK_END);
-	sample_count = ftell(samples_file_handle) / FLOAT_TO_CHAR_RATIO;
+	sample_count = ftell(samples_file_handle) / COMPLEX_SIZE;
 	rewind(samples_file_handle);
 
-	samples_file_content = malloc(sample_count * sizeof(float));
-	result = fread(samples_file_content, sample_count, 1, samples_file_handle);
+	samples_file_content = malloc(sample_count * sizeof(TRXComplex));
+	result = fread(samples_file_content, sample_count * sizeof(TRXComplex), 1, samples_file_handle);
 
 	if(result != 1) {
 		fprintf(stderr, "trx_play: could not read samples from file\n");
 		return -1;
 	}
 
-	trx_play_ctx->samples = (float *) samples_file_content;
+	trx_play_ctx->samples = (TRXComplex *) samples_file_content;
 	trx_play_ctx->sample_count = sample_count;
 	trx_play_ctx->current_sample = 0;
 
-	printf("trx_play: looping %u frames\n", sample_count);
+	printf("trx_play: looping %u frames from %s\n", sample_count, samples_file_path);
 
 	s->opaque = trx_play_ctx;
 	s->trx_start_func2 = trx_play_start;

trx-bridge/bridge.c

@@ -156,11 +156,13 @@ int main(int argc, char *argv[]) {
 	int (*input_lib_init)(TRXState *s);
 	int (*output_lib_init)(TRXState *s);
 
-	float *input_samples = malloc(8192 * sizeof(float));
-	float *input_channels[2] = { input_samples, &input_samples[4096] };
+	// IQ samples are complex numbers
+	// A flat plane of Complex is created for all channels
+	TRXComplex *input_samples = malloc(8192 * sizeof(TRXComplex));
+	TRXComplex *input_channels[2] = { input_samples, &input_samples[4096] };
 
-	float *output_samples = malloc(8192 * sizeof(float));
-	float *output_channels[2] = { output_samples, &output_samples[4096] };
+	TRXComplex *output_samples = malloc(8192 * sizeof(TRXComplex));
+	TRXComplex *output_channels[2] = { output_samples, &output_samples[4096] };
 
 	while((opt = getopt(argc, argv, "c:p:")) != -1) {
 		if(opt == 'c') {
@@ -306,7 +308,7 @@ int main(int argc, char *argv[]) {
 		count = input_trx_state.trx_read_func2(&input_trx_state, &input_ts, (void **) input_channels, count, 0, &read_md);
 		input_ts += count;
 
-		output_trx_state.trx_write_func2(&output_trx_state, input_ts, (const void **) input_channels, count / 2, 0, &write_md);
+		output_trx_state.trx_write_func2(&output_trx_state, input_ts, (const void **) input_channels, count, 0, &write_md);
 	}
 
 	dlclose(input_lib_handle);