diff --git a/src/rtl_fm.c b/src/rtl_fm.c index 35c57f8..39f3522 100644 --- a/src/rtl_fm.c +++ b/src/rtl_fm.c @@ -763,71 +763,6 @@ int squelch_to_rms(int db, struct dongle_state *dongle, struct demod_state *demo return (int)linear + 1; } -void arbitrary_upsample(int16_t *buf1, int16_t *buf2, int len1, int len2) -/* linear interpolation, len1 < len2 */ -{ - int i = 1; - int j = 0; - int tick = 0; - double frac; // use integers... - while (j < len2) { - frac = (double)tick / (double)len2; - buf2[j] = (int16_t)(buf1[i-1]*(1-frac) + buf1[i]*frac); - j++; - tick += len1; - if (tick > len2) { - tick -= len2; - i++; - } - if (i >= len1) { - i = len1 - 1; - tick = len2; - } - } -} - -void arbitrary_downsample(int16_t *buf1, int16_t *buf2, int len1, int len2) -/* fractional boxcar lowpass, len1 > len2 */ -{ - int i = 1; - int j = 0; - int tick = 0; - double remainder = 0; - double frac; // use integers... - buf2[0] = 0; - while (j < len2) { - frac = 1.0; - if ((tick + len2) > len1) { - frac = (double)(len1 - tick) / (double)len2;} - buf2[j] += (int16_t)((double)buf1[i] * frac + remainder); - remainder = (double)buf1[i] * (1.0-frac); - tick += len2; - i++; - if (tick > len1) { - j++; - buf2[j] = 0; - tick -= len1; - } - if (i >= len1) { - i = len1 - 1; - tick = len1; - } - } - for (j=0; j