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PiFmRds
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Code cleanup 

whitespaces instead of tabs, see ad766936dc
This commit is contained in:
Florian Schöck 2016-03-12 17:32:38 +01:00
parent ad766936dc
commit 3629b9ec46
1 changed files with 26 additions and 26 deletions
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52
src/fm_mpx.c
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@ -121,17 +121,17 @@ int fm_mpx_open(char *filename, size_t len) {
} else {
printf("1 channel, monophonic operation.\n");
}
// Create the preemphasis
last_buffer_val = (float*) malloc(sizeof(float)*channels);
for(int i=0;i<channels;i++) last_buffer_val[i] = 0;
preemphasis_corner_freq = 2120; //3.185kHz for Europe, 2,120kHz for US
preemphasis_prewarp = tan(PI*preemphasis_corner_freq/in_samplerate);
preemphasis_coefficient_a = (1.0 - preemphasis_prewarp)/(1.0 + preemphasis_prewarp);
preemphasis_coefficient_b = (1.0 + preemphasis_coefficient_a)/2.0;
printf("Created preemphasis with \n%lf \n%lf \n%lf \n%lf", preemphasis_corner_freq, preemphasis_prewarp, preemphasis_coefficient_a, preemphasis_coefficient_b);
// Create the preemphasis
last_buffer_val = (float*) malloc(sizeof(float)*channels);
for(int i=0;i<channels;i++) last_buffer_val[i] = 0;
preemphasis_corner_freq = 2120; //3.185kHz for Europe, 2,120kHz for US
preemphasis_prewarp = tan(PI*preemphasis_corner_freq/in_samplerate);
preemphasis_coefficient_a = (1.0 - preemphasis_prewarp)/(1.0 + preemphasis_prewarp);
preemphasis_coefficient_b = (1.0 + preemphasis_coefficient_a)/2.0;
printf("Created preemphasis with \n%lf \n%lf \n%lf \n%lf", preemphasis_corner_freq, preemphasis_prewarp, preemphasis_coefficient_a, preemphasis_coefficient_b);
// Create the low-pass FIR filter
float cutoff_freq = 15000 * .8;
@ -197,21 +197,21 @@ int fm_mpx_get_samples(float *mpx_buffer) {
return -1;
}
} else {
//apply preemphasis
int k;
int l;
float tmp;
for(k=0;k<audio_len;k+=channels) {
for(l=0;l<channels;l++) {
tmp = audio_buffer[k+l];
audio_buffer[k+l] = preemphasis_coefficient_b*audio_buffer[k+l] -
preemphasis_coefficient_b*last_buffer_val[l] +
preemphasis_coefficient_a*last_buffer_val[l];
last_buffer_val[l] = tmp;
}
}
//apply preemphasis
int k;
int l;
float tmp;
for(k=0;k<audio_len;k+=channels) {
for(l=0;l<channels;l++) {
tmp = audio_buffer[k+l];
audio_buffer[k+l] = preemphasis_coefficient_b*audio_buffer[k+l] -
preemphasis_coefficient_b*last_buffer_val[l] +
preemphasis_coefficient_a*last_buffer_val[l];
last_buffer_val[l] = tmp;
}
}
break;
}
}