1 files changed, 97 insertions, 0 deletions
diff --git a/pjmedia/src/pjmedia-codec/speex/medfilter.c b/pjmedia/src/pjmedia-codec/speex/medfilter.c
new file mode 100644
index 00000000..83872e54
--- /dev/null
+++ b/pjmedia/src/pjmedia-codec/speex/medfilter.c
@@ -0,0 +1,97 @@
+/* Copyright (C) 2004 Jean-Marc Valin
+   File medfilter.c
+   Median filter
+
+
+   Redistribution and use in source and binary forms, with or without
+   modification, are permitted provided that the following conditions
+   are met:
+   
+   - Redistributions of source code must retain the above copyright
+   notice, this list of conditions and the following disclaimer.
+   
+   - Redistributions in binary form must reproduce the above copyright
+   notice, this list of conditions and the following disclaimer in the
+   documentation and/or other materials provided with the distribution.
+   
+   - Neither the name of the Xiph.org Foundation nor the names of its
+   contributors may be used to endorse or promote products derived from
+   this software without specific prior written permission.
+   
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+   ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+   A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR
+   CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+*/
+
+#include "medfilter.h"
+#include "misc.h"
+
+MedianFilter *median_filter_new(int N)
+{
+   MedianFilter *f = (MedianFilter*)speex_alloc(sizeof(MedianFilter));
+   f->N = N;
+   f->ids = (int*)speex_alloc(sizeof(int)*N);
+   f->val = (float*)speex_alloc(sizeof(float)*N);
+   f->filled = 0;
+   return f;
+}
+
+void median_filter_update(MedianFilter *f, float val)
+{
+   int i=0;
+   int insert = 0;
+   while (insert<f->filled && f->val[insert] < val)
+   {
+      insert++;
+   }
+   if (f->filled == f->N)
+   {
+      int remove;
+      for (remove=0;remove<f->N;remove++)
+         if (f->ids[remove] == 0)
+            break;
+      if (insert>remove)
+         insert--;
+      if (insert > remove)
+      {
+         for (i=remove;i<insert;i++)
+         {
+            f->val[i] = f->val[i+1];
+            f->ids[i] = f->ids[i+1];
+         }
+      } else if (insert < remove)
+      {
+         for (i=remove;i>insert;i--)
+         {
+            f->val[i] = f->val[i-1];
+            f->ids[i] = f->ids[i-1];
+         }
+      }
+      for (i=0;i<f->filled;i++)
+         f->ids[i]--;
+   } else {
+      for (i=f->filled;i>insert;i--)
+      {
+         f->val[i] = f->val[i-1];
+         f->ids[i] = f->ids[i-1];
+      }
+      f->filled++;
+   }
+   f->val[insert]=val;
+   f->ids[insert]=f->filled-1;
+}
+
+float median_filter_get(MedianFilter *f)
+{
+   return f->val[f->filled>>1];
+}
+