* init table once

Originally committed as revision 1203 to svn://svn.ffmpeg.org/ffmpeg/trunk

libavcodec/dsputil.c

@@ -1344,8 +1344,10 @@ static void clear_blocks_c(DCTELEM *blocks)
 
 void dsputil_init(DSPContext* c, unsigned mask)
 {
+    static int init_done = 0;
     int i;
 
+    if (!init_done) {
 	for(i=0;i<256;i++) cropTbl[i + MAX_NEG_CROP] = i;
 	for(i=0;i<MAX_NEG_CROP;i++) {
 	    cropTbl[i] = 0;
@@ -1355,6 +1357,8 @@ void dsputil_init(DSPContext* c, unsigned mask)
 	for(i=0;i<512;i++) {
 	    squareTbl[i] = (i - 256) * (i - 256);
 	}
+        init_done = 1;
+    }
 
     c->get_pixels = get_pixels_c;
     c->diff_pixels = diff_pixels_c;