version 1.3

2026-11-14 09:47:30 -05:00 · 2011-08-21 03:31:35 -04:00
commit 59f8d3890e
36 changed files with 8441 additions and 0 deletions
--- a/dsd_upsample.c
+++ b/dsd_upsample.c
@@ -0,0 +1,171 @@
+/*
+ * Copyright (C) 2010 DSD Author
+ * GPG Key ID: 0x3F1D7FD0 (74EF 430D F7F2 0A48 FCE6  F630 FAA2 635D 3F1D 7FD0)
+ *
+ * Permission to use, copy, modify, and/or distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES WITH
+ * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
+ * AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR ANY SPECIAL, DIRECT,
+ * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
+ * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE
+ * OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR
+ * PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include "dsd.h"
+
+void
+upsample (dsd_state * state, float invalue)
+{
+
+  int i, j, sum;
+  float *outbuf1, a, b, c, d;
+  float phasestart, phaseend, resamplestart, resampleend, phasestep, resampleamp2;
+  float resamplemin, resamplemax;
+
+  if (state->audio_out_idx2 > 23)
+    {
+      outbuf1 = state->audio_out_float_buf_p;
+      outbuf1--;
+      c = *outbuf1;
+      outbuf1 -= 6;
+      b = *outbuf1;
+      outbuf1 -= 6;
+      a = *outbuf1;
+      d = (invalue);
+      resamplemin = 32767;
+      resamplemax = -32768;
+      if (a < resamplemin)
+        {
+          resamplemin = a;
+        }
+      if (a > resamplemax)
+        {
+          resamplemax = a;
+        }
+      if (b < resamplemin)
+        {
+          resamplemin = b;
+        }
+      if (b > resamplemax)
+        {
+          resamplemax = b;
+        }
+      if (c < resamplemin)
+        {
+          resamplemin = c;
+        }
+      if (c > resamplemax)
+        {
+          resamplemax = c;
+        }
+      if (d < resamplemin)
+        {
+          resamplemin = d;
+        }
+      if (d > resamplemax)
+        {
+          resamplemax = d;
+        }
+      resampleamp2 = ((float) resamplemax - (float) resamplemin) / (float) 2;
+#ifdef UPSAMPLE_DEBUG
+      printf ("a:%f b:%f c:%f d:%f resamplemin:%f resamplemax:%f resampleamp2:%f\n", a, b, c, d, resamplemin, resamplemax, resampleamp2);
+#endif
+      if (resampleamp2 == 0)
+        {
+          resamplestart = (float) 0;
+          resampleend = (float) 0;
+        }
+      else
+        {
+          resamplestart = (((float) b - (float) resamplemin) / resampleamp2) - (float) 1.0;
+          resampleend = (((float) c - (float) resamplemin) / resampleamp2) - (float) 1.0;
+        }
+
+      if (resamplestart < -1)
+        {
+          resamplestart = (float) -1;
+        }
+      else if (resamplestart > (float) 1)
+        {
+          resamplestart = (float) 1;
+        }
+      if (resampleend < -1)
+        {
+          resampleend = (float) -1;
+        }
+      else if (resampleend > (float) 1)
+        {
+          resampleend = (float) 1;
+        }
+
+      phasestart = asinf (resamplestart);
+      phaseend = asinf (resampleend);
+      phasestep = (phaseend - phasestart) / 6;
+#ifdef UPSAMPLE_DEBUG
+      printf ("resamplestart:%f, resampleend:%f, phasestart:%f, phaseend:%f, phasestep:%f\n", resamplestart, resampleend, phasestart, phaseend, phasestep);
+#endif
+
+      // rewrite samples between b and c
+      outbuf1 = state->audio_out_float_buf_p;
+      outbuf1 -= 6;
+      for (i = 1; i < 6; i++)
+        {
+          *outbuf1 = (resamplemin + resampleamp2 + (resampleamp2 * sin (phasestart + (phasestep * (float) i))));
+#ifdef UPSAMPLE_DEBUG
+          printf ("audio_out_idx2:%i outbuf:%f\n", state->audio_out_idx2, *outbuf1);
+#endif
+          outbuf1++;
+        }
+#ifdef UPSAMPLE_DEBUG
+      printf ("(c):%f\n", *outbuf1);
+#endif
+      // write d
+      outbuf1 += 6;
+      *outbuf1 = d;
+#ifdef UPSAMPLE_DEBUG
+      printf ("audio_out_idx2:%i outbuf(d):%f\n", state->audio_out_idx2, *outbuf1);
+#endif
+      outbuf1++;
+
+      // smooth
+      outbuf1 -= 36;
+      for (j = 0; j < 12; j++)
+        {
+          for (i = 0; i < 12; i++)
+            {
+              sum = 0;
+              outbuf1--;
+              sum += *outbuf1;
+              outbuf1++;
+              sum += *outbuf1;
+              outbuf1++;
+              sum += *outbuf1;
+              outbuf1--;
+              *outbuf1 = (sum / (float) 3);
+              outbuf1++;
+            }
+          outbuf1 -= 11;
+        }
+    }
+  else
+    {
+      outbuf1 = state->audio_out_float_buf_p;
+      outbuf1--;
+      c = *outbuf1;
+      *outbuf1 = ((invalue * (float) 0.166) + (c * (float) 0.834));
+      outbuf1++;
+      *outbuf1 = ((invalue * (float) 0.332) + (c * (float) 0.668));
+      outbuf1++;
+      *outbuf1 = ((invalue * (float) 0.5) + (c * (float) 0.5));
+      outbuf1++;
+      *outbuf1 = ((invalue * (float) 0.668) + (c * (float) 0.332));
+      outbuf1++;
+      *outbuf1 = ((invalue * (float) 0.834) + (c * (float) 0.166));
+      outbuf1++;
+      *outbuf1 = invalue;
+    }
+}