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polar stereo?

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Kuba 2024-07-01 15:58:54 +02:00 committed by GitHub
parent 09fd9646d6
commit 66ce9482cd
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1 changed files with 5 additions and 3 deletions
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8
src/pifmrds/fm_mpx.c
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@ -46,9 +46,9 @@ float low_pass_fir[FIR_PHASES][FIR_TAPS];
float carrier_38[] = {0.0, 0.8660254037844386, 0.8660254037844388, 1.2246467991473532e-16, -0.8660254037844384, -0.8660254037844386}; float carrier_38[] = {0.0, 0.8660254037844386, 0.8660254037844388, 1.2246467991473532e-16, -0.8660254037844384, -0.8660254037844386};
float carrier_19[] = {0.0, 0.5, 0.8660254037844386, 1.0, 0.8660254037844388, 0.5, 1.2246467991473532e-16, -0.5, -0.8660254037844384, -1.0, -0.8660254037844386, -0.5}; //can someone generate a 31.25 khz carrier? float carrier_19[] = {0.0, 0.5, 0.8660254037844386, 1.0, 0.8660254037844388, 0.5, 1.2246467991473532e-16, -0.5, -0.8660254037844384, -1.0, -0.8660254037844386, -0.5};
float carrier_3125[] = {0.0, 0.8660254037844386, 0.8660254037844388, 1.2246467991473532e-16, -0.8660254037844384, -0.8660254037844386}; float carrier_3125[] = {0.0, 0.7586133425663026, 0.9885355334735083, 0.5295297022607088, -0.29851481100169425, -0.918519035014914, -0.898390981891979, -0.2521582503964708};
int phase_38 = 0; int phase_38 = 0;
int phase_3125 = 0; int phase_3125 = 0;
@ -362,8 +362,10 @@ int fm_mpx_get_samples(float *mpx_buffer, int drds, float compressor_decay, floa
if(phase_38 >= 6) phase_38 = 0; if(phase_38 >= 6) phase_38 = 0;
} else { // polar stereo (https://forums.stereotool.com/viewtopic.php?t=6233, https://personal.utdallas.edu/~dlm/3350%20comm%20sys/ITU%20std%20on%20FM%20--%20R-REC-BS.450-3-200111-I!!PDF-E.pdf) } else { // polar stereo (https://forums.stereotool.com/viewtopic.php?t=6233, https://personal.utdallas.edu/~dlm/3350%20comm%20sys/ITU%20std%20on%20FM%20--%20R-REC-BS.450-3-200111-I!!PDF-E.pdf)
mpx_buffer[i] += 4.05*(out_left+out_right) + // Stereo sum signal (L+R) mpx_buffer[i] += 4.05*(out_left+out_right) + // Stereo sum signal (L+R)
4.05 * (out_left-out_right); // Stereo difference signal 4.05 * carrier_3125[phase_3125] * (out_left-out_right); // Stereo difference signal
//NO PIOT TONE!!!!!!!!!!!!!!!!!!!!!!!!!!!! (its missplelled correctly probably just like misspelled) //NO PIOT TONE!!!!!!!!!!!!!!!!!!!!!!!!!!!! (its missplelled correctly probably just like misspelled)
phase_3125++;
if(phase_3125 >= 8) phase_3125 = 0;
} }
} }
} else { } else {