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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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42
src/fm_mpx.c
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@ -122,15 +122,15 @@ int fm_mpx_open(char *filename, size_t len) {
printf("1 channel, monophonic operation.\n"); printf("1 channel, monophonic operation.\n");
} }
// Create the preemphasis // Create the preemphasis
last_buffer_val = (float*) malloc(sizeof(float)*channels); last_buffer_val = (float*) malloc(sizeof(float)*channels);
for(int i=0;i<channels;i++) last_buffer_val[i] = 0; 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_corner_freq = 2120; //3.185kHz for Europe, 2,120kHz for US
preemphasis_prewarp = tan(PI*preemphasis_corner_freq/in_samplerate); preemphasis_prewarp = tan(PI*preemphasis_corner_freq/in_samplerate);
preemphasis_coefficient_a = (1.0 - preemphasis_prewarp)/(1.0 + preemphasis_prewarp); preemphasis_coefficient_a = (1.0 - preemphasis_prewarp)/(1.0 + preemphasis_prewarp);
preemphasis_coefficient_b = (1.0 + preemphasis_coefficient_a)/2.0; 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); 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 // Create the low-pass FIR filter
@ -197,20 +197,20 @@ int fm_mpx_get_samples(float *mpx_buffer) {
return -1; return -1;
} }
} else { } else {
//apply preemphasis //apply preemphasis
int k; int k;
int l; int l;
float tmp; float tmp;
for(k=0;k<audio_len;k+=channels) { for(k=0;k<audio_len;k+=channels) {
for(l=0;l<channels;l++) { for(l=0;l<channels;l++) {
tmp = audio_buffer[k+l]; tmp = audio_buffer[k+l];
audio_buffer[k+l] = preemphasis_coefficient_b*audio_buffer[k+l] - audio_buffer[k+l] = preemphasis_coefficient_b*audio_buffer[k+l] -
preemphasis_coefficient_b*last_buffer_val[l] + preemphasis_coefficient_b*last_buffer_val[l] +
preemphasis_coefficient_a*last_buffer_val[l]; preemphasis_coefficient_a*last_buffer_val[l];
last_buffer_val[l] = tmp; last_buffer_val[l] = tmp;
} }
} }
break; break;
} }