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-rw-r--r--media/libtremor/lib/tremor_window.c83
1 files changed, 83 insertions, 0 deletions
diff --git a/media/libtremor/lib/tremor_window.c b/media/libtremor/lib/tremor_window.c
new file mode 100644
index 000000000..006a1ee6b
--- /dev/null
+++ b/media/libtremor/lib/tremor_window.c
@@ -0,0 +1,83 @@
+/********************************************************************
+ * *
+ * THIS FILE IS PART OF THE OggVorbis 'TREMOR' CODEC SOURCE CODE. *
+ * *
+ * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS *
+ * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
+ * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING. *
+ * *
+ * THE OggVorbis 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2002 *
+ * BY THE Xiph.Org FOUNDATION http://www.xiph.org/ *
+ * *
+ ********************************************************************
+
+ function: window functions
+
+ ********************************************************************/
+
+#include <stdlib.h>
+#include <math.h>
+#include "misc.h"
+#include "window.h"
+#include "window_lookup.h"
+
+const void *_vorbis_window(int type, int left){
+
+ switch(type){
+ case 0:
+
+ switch(left){
+ case 32:
+ return vwin64;
+ case 64:
+ return vwin128;
+ case 128:
+ return vwin256;
+ case 256:
+ return vwin512;
+ case 512:
+ return vwin1024;
+ case 1024:
+ return vwin2048;
+ case 2048:
+ return vwin4096;
+ case 4096:
+ return vwin8192;
+ default:
+ return(0);
+ }
+ break;
+ default:
+ return(0);
+ }
+}
+
+void _vorbis_apply_window(ogg_int32_t *d,const void *window_p[2],
+ long *blocksizes,
+ int lW,int W,int nW){
+
+ LOOKUP_T *window[2]={window_p[0],window_p[1]};
+ long n=blocksizes[W];
+ long ln=blocksizes[lW];
+ long rn=blocksizes[nW];
+
+ long leftbegin=n/4-ln/4;
+ long leftend=leftbegin+ln/2;
+
+ long rightbegin=n/2+n/4-rn/4;
+ long rightend=rightbegin+rn/2;
+
+ int i,p;
+
+ for(i=0;i<leftbegin;i++)
+ d[i]=0;
+
+ for(p=0;i<leftend;i++,p++)
+ d[i]=MULT31(d[i],window[lW][p]);
+
+ for(i=rightbegin,p=rn/2-1;i<rightend;i++,p--)
+ d[i]=MULT31(d[i],window[nW][p]);
+
+ for(;i<n;i++)
+ d[i]=0;
+}