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Eliminate clipping from the low-pass filter stage by increasing intermediate buffer type size to int

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

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

@@ -61,7 +61,7 @@

     unsigned int phase_inc;

     float a1, a2, b02, b1;

     float yn1, yn2;

-    short buffer_in[fir_buffer_size * 2];

+    int buffer_in[fir_buffer_size * 2];

     int buffer_out[fir_buffer_size];

 } fir_resampler;

@@ -166,23 +166,22 @@

     if ( r->write_filled < fir_buffer_size )

 	{

+        int s32 = s;

+

         if ( r->phase_inc > 65536 )

         {

             /* The filter is implemented in Direct-II form. */

-            int s32;

             float in, out, dsp_centernode;

-            in = s;

+            in = s32;

             dsp_centernode = in - r->a1 * r->yn1 - r->a2 * r->yn2;

             out = r->b02 * (dsp_centernode + r->yn2) + r->b1 * r->yn1;

             r->yn2 = r->yn1;

             r->yn1 = dsp_centernode;

             s32 = out;

-            if ( (unsigned)(s32 + 0x8000) >= 0x10000 ) s32 = (s32 >> 31) ^ 0x7FFF;

-            s = (short) s32;

         }

-        r->buffer_in[ r->write_pos ] = s;

-        r->buffer_in[ r->write_pos + fir_buffer_size ] = s;

+        r->buffer_in[ r->write_pos ] = s32;

+        r->buffer_in[ r->write_pos + fir_buffer_size ] = s32;

         ++r->write_filled;

@@ -220,14 +219,14 @@

 {

 	fir_resampler * r = ( fir_resampler * ) _r;

     int in_size = r->write_filled;

-    short const* in_ = r->buffer_in + fir_buffer_size + r->write_pos - r->write_filled;

+    int const* in_ = r->buffer_in + fir_buffer_size + r->write_pos - r->write_filled;

 	int used = 0;

 	in_size -= fir_write_offset;

 	if ( in_size > 0 )

 	{

 		int* out = *out_;

-		short const* in = in_;

-		short const* const in_end = in + in_size;

+		int const* in = in_;

+		int const* const in_end = in + in_size;

         int phase = r->phase;

         int phase_inc = r->phase_inc;