view tools/audio_processor_test/fir/checker/checker.cpp @ 76:8bd0e4d37ad2 pygar svn.77 tip

[svn r77] I don't know why my last change didn't go through grumble grumble....
author rlm
date Wed, 12 May 2010 08:58:23 -0400
parents 90197e3375e2
children
line wrap: on
line source
1 #include <stdio.h>
2 #include <assert.h>
3 #include <string.h>
4 #include "SndfileWavUtil.h"
6 const int Taps = 9;
7 static int newest;
8 static short int x[Taps] = {0,0,0,0,0,0,0,0,0};
9 static short int fir(short int);
10 const int short_sz = sizeof(short);
12 // lifted from the bluespec code
13 static double h[Taps] = {-0.0124,
14 0.0,
15 -0.0133,
16 0.0,
17 0.8181,
18 0.0,
19 -0.0133,
20 0.0,
21 -0.0124};
24 int
25 main (int argc, char * argv [])
26 {
27 const char* inputWavFileName;
28 const char* outputWavFileName;
30 FILE *inputPcmFile;
31 FILE *outputPcmFile;
33 short int sample;
35 inputWavFileName = argv[1];
36 outputWavFileName = argv[2];
38 // Convert input wav to pcm
39 generate_pcm(inputWavFileName, "input.pcm");
41 inputPcmFile = fopen("input.pcm", "r");
42 outputPcmFile = fopen("output.pcm", "w");
44 assert(inputPcmFile);
45 assert(outputPcmFile);
47 newest = 0;
48 memset(x, 0, sizeof(x));
50 while(fread(&sample, short_sz, 1, inputPcmFile)) {
51 sample = fir(sample);
52 assert(fwrite(&sample,short_sz,1,outputPcmFile));
53 }
55 fclose(inputPcmFile);
56 fclose(outputPcmFile);
58 generate_wav("output.pcm", inputWavFileName, outputWavFileName);
59 }
61 short int
62 fir(short int sample)
63 {
65 x[newest] = sample;
66 double y = 0;
68 for (int k = 0; k < Taps; k++) {
70 short int bits = x[(newest+k)%Taps];
71 double x = (double)bits;
72 y += h[k] * x;
74 }
76 newest = (newest == 0) ? (Taps-1) : (newest-1);
78 short int rv = ((short int)y)&0x0000FFFF;
79 return rv;
80 }