resampler unit test

git-svn-id: https://svn.code.sf.net/p/freetel/code@1769 01035d8c-6547-0410-b346-abe4f91aad63

diff --git a/codec2-dev/unittest/t16_8.c b/codec2-dev/unittest/t16_8.c
new file mode 100644 (file)
index 0000000..c9ad3f5
--- /dev/null
+++ b/codec2-dev/unittest/t16_8.c
@@ -0,0 +1,112 @@
+/* 
+   t16_8.c
+   David Rowe
+   May 10 2012
+
+   Unit test for 16 to 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 <stdlib.h>
+#include <stdio.h>
+#include "codec2_fdmdv.h"
+
+#define N8                        160 /* procssing buffer size at 8 kHz */
+#define N16             (N8*FDMDV_OS)
+#define MEM8 (FDMDV_OS_TAPS/FDMDV_OS)
+#define FRAMES                     50
+#define TWO_PI            6.283185307
+#define FS                       8000
+
+#define SINE
+
+int main() {
+    float in8k[MEM8 + N8];
+    float out16k[N16];
+    short out16k_short[N16];
+    FILE *f16;
+
+    float in16k[FDMDV_OS_TAPS + N16];
+    float out8k[N16];
+    short out8k_short[N8];
+    FILE *f8;
+
+    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);
+    
+    /* clear filter memories */
+
+    for(i=0; i<MEM8; i++)
+       in8k[i] = 0.0;
+    for(i=0; i<FDMDV_OS_TAPS; i++)
+       in16k[i] = 0.0;
+
+    t = t1 = 0;
+    for(f=0; f<FRAMES; f++) {
+
+#ifdef DC
+       for(i=0; i<N8; i++)
+           in8k[MEM8+i] = 16000.0;
+#endif
+#ifdef SINE
+       for(i=0; i<N8; i++,t++)
+           in8k[MEM8+i] = 16000.0*cos(TWO_PI*t*freq/FS);
+#endif
+
+       /* upsample  */
+
+       fdmdv_8_to_16(out16k, &in8k[MEM8], N8);
+       /*
+       for(i=0; i<MEM8; i++)
+           in8k[i] = in8k[i+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 10 kHz spurious signal for fun, we want down sampler to
+          knock this out */
+
+       for(i=0; i<N16; i++,t1++)
+           in16k[i+FDMDV_OS_TAPS] = out16k[i] + 16000.0*cos(TWO_PI*t1*1E4/FS);
+
+       /* downsample */
+
+       fdmdv_16_to_8(out8k, &in16k[FDMDV_OS_TAPS], N8);
+       /*
+       for(i=0; i<FDMDV_OS_TAPS; i++)
+           in16k[i] = in16k[i+N16];
+       */
+
+       /* 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);
+    return 0;
+
+}