Remove the sinc4 table

1 files changed, 4 insertions, 43 deletions

diff --git a/native-tools/bsincgen.c b/native-tools/bsincgen.c
index 2a7e4326..49102279 100644
--- a/native-tools/bsincgen.c
+++ b/native-tools/bsincgen.c
@@ -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);