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Move samples of int16_t format to sample_t, that is of type double

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This prepares the correction of all levels
This commit is contained in:
Andreas Eversberg
2017-01-27 16:57:34 +01:00
parent 538a959128
commit 7ea3bc188d
74 changed files with 471 additions and 447 deletions
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33
src/common/goertzel.c
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@@ -22,7 +22,8 @@
#include <string.h>
#include <errno.h>
#include <math.h>
#include "../common/debug.h"
#include "sample.h"
#include "debug.h"
#include "goertzel.h"
/*
@@ -30,9 +31,9 @@
*/
/* return average value (rectified value), that can be 0..1 */
double audio_level(int16_t *samples, int length)
double audio_level(sample_t *samples, int length)
{
int32_t bias;
double bias;
double level;
int sk;
int n;
@@ -57,6 +58,12 @@ double audio_level(int16_t *samples, int length)
return level;
}
void audio_goertzel_init(goertzel_t *goertzel, double freq, int samplerate)
{
memset(goertzel, 0, sizeof(*goertzel));
goertzel->coeff = 2.0 * cos(2.0 * M_PI * freq / (double)samplerate);
}
/*
* goertzel filter
*/
@@ -70,11 +77,11 @@ double audio_level(int16_t *samples, int length)
* result: array of result levels (average value of the sine, that is 1 / (PI/2) of the sine's peak)
* k: number of frequencies to check
*/
void audio_goertzel(int16_t *samples, int length, int offset, int *coeff, double *result, int k)
void audio_goertzel(goertzel_t *goertzel, sample_t *samples, int length, int offset, double *result, int k)
{
int32_t bias;
int32_t sk, sk1, sk2;
int64_t cos2pik;
double bias;
double sk, sk1, sk2;
double cos2pik;
int i, n;
/* calculate bias to remove DC */
@@ -88,10 +95,10 @@ void audio_goertzel(int16_t *samples, int length, int offset, int *coeff, double
sk = 0;
sk1 = 0;
sk2 = 0;
cos2pik = coeff[i];
cos2pik = goertzel[i].coeff;
/* note: after 'length' cycles, offset is restored to its initial value */
for (n = 0; n < length; n++) {
sk = ((cos2pik * sk1) >> 15) - sk2 + samples[offset++] - bias;
sk = (cos2pik * sk1) - sk2 + samples[offset++] - bias;
sk2 = sk1;
sk1 = sk;
if (offset == length)
@@ -99,10 +106,10 @@ void audio_goertzel(int16_t *samples, int length, int offset, int *coeff, double
}
/* compute level of signal */
result[i] = sqrt(
((double)sk * (double)sk) -
((double)((cos2pik * sk) >> 15) * (double)sk2) +
((double)sk2 * (double)sk2)
) / (double)length / 32767.0 * 2.0 * 0.63662; /* 1 / (PI/2) */
(sk * sk) -
(cos2pik * sk * sk2) +
(sk2 * sk2)
) / (double)length * 2.0 * 0.63662; /* 1 / (PI/2) */
}
}