[FFmpeg-cvslog] r11881 - trunk/libavcodec/flacenc.c

[michael]

Author: michael
Date: Sat Feb  9 04:42:48 2008
New Revision: 11881

Log:
optimize apply_welch_window()


Modified:
   trunk/libavcodec/flacenc.c

Modified: trunk/libavcodec/flacenc.c
==============================================================================
--- trunk/libavcodec/flacenc.c	(original)
+++ trunk/libavcodec/flacenc.c	Sat Feb  9 04:42:48 2008
@@ -595,11 +595,14 @@ static void apply_welch_window(const int
 
     n2 = (len >> 1);
     c = 2.0 / (len - 1.0);
+
+    w_data+=n2;
+      data+=n2;
     for(i=0; i<n2; i++) {
-        w = c - i - 1.0;
+        w = c - n2 + i;
         w = 1.0 - (w * w);
-        w_data[i] = data[i] * w;
-        w_data[len-1-i] = data[len-1-i] * w;
+        w_data[-i-1] = data[-i-1] * w;
+        w_data[+i  ] = data[+i  ] * w;
     }
 }