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Rebuild full ResamplerFilter (left wing + right wing) at runtime

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Brick 2023-08-24 00:18:52 +01:00 • committed by Ryan C. Gordon
parent 0c15ce0060
commit 6a73f74b6b
4 changed files with 53 additions and 33 deletions
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14
build-scripts/gen_audio_resampler_filter.c
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@ -50,7 +50,6 @@ gcc -o genfilter build-scripts/gen_audio_resampler_filter.c -lm && ./genfilter >
#define RESAMPLER_BITS_PER_ZERO_CROSSING ((RESAMPLER_BITS_PER_SAMPLE / 2) + 1)
#define RESAMPLER_SAMPLES_PER_ZERO_CROSSING (1 << RESAMPLER_BITS_PER_ZERO_CROSSING)
#define RESAMPLER_FILTER_SIZE (RESAMPLER_SAMPLES_PER_ZERO_CROSSING * RESAMPLER_ZERO_CROSSINGS)
#define RESAMPLER_TABLE_SIZE (RESAMPLER_FILTER_SIZE + RESAMPLER_ZERO_CROSSINGS)
/* This is a "modified" bessel function, so you can't use POSIX j0() */
static double
@ -136,18 +135,13 @@ int main(void)
"#define RESAMPLER_BITS_PER_ZERO_CROSSING ((RESAMPLER_BITS_PER_SAMPLE / 2) + 1)\n"
"#define RESAMPLER_SAMPLES_PER_ZERO_CROSSING (1 << RESAMPLER_BITS_PER_ZERO_CROSSING)\n"
"#define RESAMPLER_FILTER_SIZE (RESAMPLER_SAMPLES_PER_ZERO_CROSSING * RESAMPLER_ZERO_CROSSINGS)\n"
"#define RESAMPLER_TABLE_SIZE (RESAMPLER_FILTER_SIZE + RESAMPLER_ZERO_CROSSINGS)\n"
"\n", RESAMPLER_ZERO_CROSSINGS, RESAMPLER_BITS_PER_SAMPLE
);
printf("static const float ResamplerFilter[RESAMPLER_TABLE_SIZE] = {");
for (i = 0; i < RESAMPLER_TABLE_SIZE; i++) {
double v = 0.0;
if (i < RESAMPLER_FILTER_SIZE) {
j = (i % RESAMPLER_ZERO_CROSSINGS) * RESAMPLER_SAMPLES_PER_ZERO_CROSSING + (i / RESAMPLER_ZERO_CROSSINGS);
v = ResamplerFilter[j];
}
printf("%s%12.9ff,", (i % RESAMPLER_ZERO_CROSSINGS) ? "" : "\n ", v);
printf("static const float ResamplerFilter[RESAMPLER_FILTER_SIZE] = {");
for (i = 0; i < RESAMPLER_FILTER_SIZE; i++) {
j = (i % RESAMPLER_ZERO_CROSSINGS) * RESAMPLER_SAMPLES_PER_ZERO_CROSSING + (i / RESAMPLER_ZERO_CROSSINGS);
printf("%s%12.9ff,", (i % RESAMPLER_ZERO_CROSSINGS) ? "" : "\n ", ResamplerFilter[j]);
}
printf("\n};\n\n");