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Remove the sinc4 table

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This commit is contained in:
Chris Robinson
2018-01-07 05:58:52 -08:00
parent 4cc1c64646
commit c423b6c8b7
3 changed files with 4 additions and 53 deletions
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Alc/ALu.c
-5
View File
@@ -1046,9 +1046,6 @@ static void CalcNonAttnSourceParams(ALvoice *voice, const struct ALvoiceProps *p
BsincPrepare(voice->Step, &voice->ResampleState.bsinc, &bsinc24);
else if(props->Resampler == BSinc12Resampler)
BsincPrepare(voice->Step, &voice->ResampleState.bsinc, &bsinc12);
else
voice->ResampleState.sinc4.filter = sinc4Tab;
voice->Resampler = SelectResampler(props->Resampler);
/* Calculate gains */
@@ -1396,8 +1393,6 @@ static void CalcAttnSourceParams(ALvoice *voice, const struct ALvoiceProps *prop
BsincPrepare(voice->Step, &voice->ResampleState.bsinc, &bsinc24);
else if(props->Resampler == BSinc12Resampler)
BsincPrepare(voice->Step, &voice->ResampleState.bsinc, &bsinc12);
else
voice->ResampleState.sinc4.filter = sinc4Tab;
voice->Resampler = SelectResampler(props->Resampler);
if(Distance > FLT_EPSILON)
OpenAL32/Include/alu.h
-5
View File
@@ -84,13 +84,8 @@ typedef struct BsincState {
const ALfloat *filter;
} BsincState;
typedef struct Sinc4State {
const ALfloat (*filter)[4];
} Sinc4State;
typedef union InterpState {
BsincState bsinc;
Sinc4State sinc4;
} InterpState;
typedef const ALfloat* (*ResamplerFunc)(const InterpState *state,
native-tools/bsincgen.c
+4 -43
View File
@@ -50,6 +50,10 @@
#define log2(x) (log(x) / log(2.0))
#endif
/* Same as in alu.h! */
#define FRACTIONBITS (12)
#define FRACTIONONE (1<<FRACTIONBITS)
// The number of distinct scale and phase intervals within the filter table.
// Must be the same as in alu.h!
#define BSINC_SCALE_COUNT (16)
@@ -316,48 +320,6 @@ static void BsiGenerateTables(FILE *output, const char *tabname, const double re
}
/* These methods generate a much simplified 4-point sinc interpolator using a
* Kaiser window. This is much simpler to process at run-time, but has notably
* more aliasing noise.
*/
/* Same as in alu.h! */
#define FRACTIONBITS (12)
#define FRACTIONONE (1<<FRACTIONBITS)
static void Sinc4GenerateTables(FILE *output, const double rejection)
{
static double filter[FRACTIONONE][4];
const double width = CalcKaiserWidth(rejection, 3);
const double beta = CalcKaiserBeta(rejection);
const double scaleBase = width / 2.0;
const double scaleRange = 1.0 - scaleBase;
const double scale = scaleBase + scaleRange;
const double a = MinDouble(4.0, floor(4.0 / (2.0*scale)));
const int m = 2 * (int)a;
const int l = (m/2) - 1;
int pi;
for(pi = 0;pi < FRACTIONONE;pi++)
{
const double phase = l + ((double)pi / FRACTIONONE);
int i;
for(i = 0;i < m;i++)
{
double x = i - phase;
filter[pi][i] = Kaiser(beta, x / a) * Sinc(x);
}
}
fprintf(output, "alignas(16) static const float sinc4Tab[FRACTIONONE][4] = {\n");
for(pi = 0;pi < FRACTIONONE;pi++)
fprintf(output, " { %+14.9ef, %+14.9ef, %+14.9ef, %+14.9ef },\n",
filter[pi][0], filter[pi][1], filter[pi][2], filter[pi][3]);
fprintf(output, "};\n\n");
}
int main(int argc, char *argv[])
{
FILE *output;
@@ -396,7 +358,6 @@ int main(int argc, char *argv[])
BsiGenerateTables(output, "bsinc24", 60.0, 23);
/* An 11th order filter with a -60dB drop at nyquist. */
BsiGenerateTables(output, "bsinc12", 60.0, 11);
Sinc4GenerateTables(output, 60.0);
if(output != stdout)
fclose(output);