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Changed sinc window to Nuttal 3 term, and added pre-fill of silence to account for half the window size minus one

--- a/dumb/src/helpers/resampler.c

+++ b/dumb/src/helpers/resampler.c

@@ -76,9 +76,12 @@

     for (i = 0; i < SINC_SAMPLES + 1; ++i, x += dx)

     {

         float y = x / SINC_WIDTH;

-#if 1

+#if 0

         // Blackman

         float window = 0.42659 - 0.49656 * cos(M_PI + M_PI * y) + 0.076849 * cos(2.0 * M_PI * y);

+#elif 1

+        // Nuttal 3 term

+        float window = 0.40897 + 0.5 * cos(M_PI * y) + 0.09103 * cos(2.0 * M_PI * y);

 #elif 0

         // C.R.Helmrich's 2 term window

         float window = 0.79445 * cos(0.5 * M_PI * y) + 0.20555 * cos(1.5 * M_PI * y);

@@ -118,8 +121,8 @@

     resampler * r = ( resampler * ) malloc( sizeof(resampler) );

     if ( !r ) return 0;

-    r->write_pos = 0;

-    r->write_filled = 0;

+    r->write_pos = SINC_WIDTH - 1;

+    r->write_filled = SINC_WIDTH - 1;

     r->read_pos = 0;

     r->read_filled = 0;

     r->phase = 0;

@@ -215,11 +218,13 @@

 void resampler_clear(void *_r)

 {

     resampler * r = ( resampler * ) _r;

-    r->write_pos = 0;

-    r->write_filled = 0;

+    r->write_pos = SINC_WIDTH - 1;

+    r->write_filled = SINC_WIDTH - 1;

     r->read_pos = 0;

     r->read_filled = 0;

     r->phase = 0;

+	memset(r->buffer_in, 0, (SINC_WIDTH - 1) * sizeof(r->buffer_in[0]));

+	memset(r->buffer_in + resampler_buffer_size, 0, (SINC_WIDTH - 1) * sizeof(r->buffer_in[0]));

 }

 void resampler_set_rate(void *_r, double new_factor)