Emilio Monti
Example FIR filter using the draft mbed DSP API
Revision 0:9ab177799489, committed 2012-03-12
- Comitter:
- emilmont
- Date:
- Mon Mar 12 11:37:31 2012 +0000
- Child:
- 1:0814c87942ca
- Commit message:
Changed in this revision
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/main.cpp Mon Mar 12 11:37:31 2012 +0000
@@ -0,0 +1,53 @@
+#include "mbed.h"
+#include "dsp.h"
+
+#define BLOCK_SIZE (32)
+#define NUM_BLOCKS (10)
+#define TEST_LENGTH_SAMPLES (BLOCK_SIZE * NUM_BLOCKS)
+
+#define SAMPLE_RATE (48000)
+
+#define SNR_THRESHOLD_F32 (50.0f)
+
+float32_t expected_output[TEST_LENGTH_SAMPLES];
+float32_t output[TEST_LENGTH_SAMPLES];
+
+/* FIR Coefficients buffer generated using fir1() MATLAB function: fir1(28, 6/24) */
+#define NUM_TAPS 29
+const float32_t firCoeffs32[NUM_TAPS] = {
+ -0.0018225230f, -0.0015879294f, +0.0000000000f, +0.0036977508f, +0.0080754303f,
+ +0.0085302217f, -0.0000000000f, -0.0173976984f, -0.0341458607f, -0.0333591565f,
+ +0.0000000000f, +0.0676308395f, +0.1522061835f, +0.2229246956f, +0.2504960933f,
+ +0.2229246956f, +0.1522061835f, +0.0676308395f, +0.0000000000f, -0.0333591565f,
+ -0.0341458607f, -0.0173976984f, -0.0000000000f, +0.0085302217f, +0.0080754303f,
+ +0.0036977508f, +0.0000000000f, -0.0015879294f, -0.0018225230f
+};
+#define WARMUP (NUM_TAPS-1)
+#define DELAY (WARMUP/2)
+
+int main() {
+ Sine_f32 sine_1K( 1000, SAMPLE_RATE, 1.0);
+ Sine_f32 sine_15K(15000, SAMPLE_RATE, 0.5);
+ FIR_f32<NUM_TAPS> fir(firCoeffs32);
+
+ for (int i=0; i<NUM_BLOCKS; i++) {
+ float32_t *signal = output + i*BLOCK_SIZE;
+ sine_1K.process(signal);
+ sine_15K.process(signal);
+ fir.process(signal);
+ }
+
+ sine_1K.reset();
+ for (int i=0; i<NUM_BLOCKS; i++) {
+ float32_t *signal = expected_output + i*BLOCK_SIZE;
+ sine_1K.process(signal);
+ }
+
+ float snr = arm_snr_f32(&expected_output[DELAY-1], &output[WARMUP-1], TEST_LENGTH_SAMPLES-WARMUP);
+ printf("snr: %f\n\r", snr);
+ if (snr < SNR_THRESHOLD_F32) {
+ printf("Failed\n\r");
+ } else {
+ printf("Success\n\r");
+ }
+}
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed.bld Mon Mar 12 11:37:31 2012 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/mbed_official/code/mbed/builds/737756e0b479
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/mbed_dsp.lib Mon Mar 12 11:37:31 2012 +0000 @@ -0,0 +1,1 @@ +http://mbed.org/users/emilmont/code/mbed_dsp/#7e3eedc2a9fa