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authorMarin Ivanov <[email protected]>2025-07-25 10:17:14 +0300
committerMarin Ivanov <[email protected]>2026-01-18 20:09:26 +0200
commit0168586485e6310c598713c911b1dec5618d61a1 (patch)
tree6aabc2a12ef8fef70683f5389bea00f948015f77 /unittest/t16_8.c
Initial commitHEADmaster
* codec2 cut-down version 1.2.0 * Remove codebook and generation of sources * remove c2dec c2enc binaries * prepare for emscripten
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diff --git a/unittest/t16_8.c b/unittest/t16_8.c
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+/*
+ t16_8.c
+ David Rowe
+ May 10 2012
+
+ Unit test for 16 <-> 8 kHz sample rate conversion functions. I
+
+ Evaluated output by plotting using Octave and looking for jaggies:
+
+ pl("../unittest/out16.raw",1,3000)
+ pl("../unittest/out8.raw",1,3000)
+
+ Listening to it also shows up anything nasty:
+
+ $ play -s -2 -r 16000 out16.raw
+ $ play -s -2 -r 8000 out8.raw
+
+ */
+
+#include <assert.h>
+#include <math.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "codec2_fdmdv.h"
+
+#define N8 159 /* processing buffer size at 8 kHz (odd number deliberate) */
+#define N16 (N8 * FDMDV_OS)
+#define FRAMES 50
+#define TWO_PI 6.283185307
+#define FS 16000
+
+#define SINE
+
+int main() {
+ float in8k[FDMDV_OS_TAPS_8K + N8];
+ short in8k_short[N8];
+ float out16k[N16];
+ short out16k_short[N16];
+ FILE *f16;
+
+ float in16k[FDMDV_OS_TAPS_16K + N16];
+ float out8k[N16];
+ short out8k_short[N8];
+ FILE *f8, *f8in;
+
+ int i, f, t, t1;
+ float freq = 800.0;
+
+ f16 = fopen("out16.raw", "wb");
+ assert(f16 != NULL);
+ f8 = fopen("out8.raw", "wb");
+ assert(f8 != NULL);
+ f8in = fopen("in8.raw", "wb");
+ assert(f8in != NULL);
+
+ /* clear filter memories */
+ for (i = 0; i < FDMDV_OS_TAPS_8K; i++) in8k[i] = 0.0;
+ for (i = 0; i < FDMDV_OS_TAPS_16K; i++) in16k[i] = 0.0;
+
+ t = t1 = 0;
+ for (f = 0; f < FRAMES; f++) {
+#ifdef DC
+ for (i = 0; i < N8; i++) in8k[FDMDV_OS_TAPS_8K + i] = 16000.0;
+#endif
+#ifdef SINE
+ for (i = 0; i < N8; i++, t++)
+ in8k[FDMDV_OS_TAPS_8K + i] =
+ 16000.0 * cos(TWO_PI * t * freq / (FS / FDMDV_OS));
+#endif
+ for (i = 0; i < N8; i++) in8k_short[i] = (short)in8k[i];
+ fwrite(in8k_short, sizeof(short), N8, f8in);
+
+ /* upsample */
+ fdmdv_8_to_16(out16k, &in8k[FDMDV_OS_TAPS_8K], N8);
+
+ /* save 16k to disk for plotting and check out */
+ for (i = 0; i < N16; i++) out16k_short[i] = (short)out16k[i];
+ fwrite(out16k_short, sizeof(short), N16, f16);
+
+ /* add a 6 kHz spurious signal, down sampler should
+ knock this out */
+ for (i = 0; i < N16; i++, t1++)
+ in16k[i + FDMDV_OS_TAPS_16K] =
+ out16k[i] + 16000.0 * cos(TWO_PI * t1 * 6000.0 / FS);
+
+ /* downsample */
+ fdmdv_16_to_8(out8k, &in16k[FDMDV_OS_TAPS_16K], N8);
+
+ /* save 8k to disk for plotting and check out */
+ for (i = 0; i < N8; i++) out8k_short[i] = (short)out8k[i];
+ fwrite(out8k_short, sizeof(short), N8, f8);
+ }
+
+ fclose(f16);
+ fclose(f8);
+ fclose(f8in);
+ return 0;
+}