libretro/RetroArch
1
0
Fork 0
mirror of https://github.com/libretro/RetroArch.git synced 2025-01-24 10:24:55 +00:00
Code Issues Actions 24 Packages Projects Releases Wiki Activity

Add cutoff.

Browse Source
This commit is contained in:
Themaister 2012-02-26 19:16:46 +01:00
parent 60edff831a
commit afa6776b1d
2 changed files with 6 additions and 3 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

7
audio/sinc.c
View File

@ -45,8 +45,9 @@
#define PHASES_WRAP (1 << (PHASE_BITS + SUBPHASE_BITS))
#define FRAMES_SHIFT (PHASE_BITS + SUBPHASE_BITS)
#define SIDELOBES 16
#define SIDELOBES 32
#define TAPS (SIDELOBES * 2)
#define CUTOFF 0.9
#define PHASE_INDEX 0
#define DELTA_INDEX 1
@ -94,7 +95,7 @@ static void init_sinc_table(ssnes_resampler_t *resamp)
{
double p = (double)i / PHASES;
double sinc_phase = M_PI * (p + (SIDELOBES - 1 - j));
resamp->phase_table[i][PHASE_INDEX][j] = sinc(sinc_phase) *
resamp->phase_table[i][PHASE_INDEX][j] = CUTOFF * sinc(CUTOFF * sinc_phase) *
lanzcos(sinc_phase / SIDELOBES);
}
}
@ -114,7 +115,7 @@ static void init_sinc_table(ssnes_resampler_t *resamp)
{
double p = 1.0;
double sinc_phase = M_PI * (p + (SIDELOBES - 1 - j));
double phase = sinc(sinc_phase) * lanzcos(sinc_phase / SIDELOBES);
double phase = CUTOFF * sinc(CUTOFF * sinc_phase) * lanzcos(sinc_phase / SIDELOBES);
float result = (phase - resamp->phase_table[PHASES - 1][PHASE_INDEX][j]) / SUBPHASES;
resamp->phase_table[PHASES - 1][DELTA_INDEX][j] = result;

2
audio/test/snr.c
View File

@ -75,6 +75,8 @@ struct snr_result
double phase;
};
// This doesn't yet take account for slight phase distortions,
// so reported SNR is lower than reality.
static void calculate_snr(struct snr_result *res,
double omega,
float *orig, const float *resamp, size_t samples)