@@ -355,38 +355,45 @@ void ff_emulated_edge_mc(uint8_t *buf, const uint8_t *src, int linesize, int blo

     start_x= FFMAX(0, -src_x);

     end_y= FFMIN(block_h, h-src_y);

     end_x= FFMIN(block_w, w-src_x);

+    assert(start_y < end_y && block_h);

+    assert(start_x < end_x && block_w);

-    // copy existing part

-    for(y=start_y; y<end_y; y++){

-        for(x=start_x; x<end_x; x++){

-            buf[x + y*linesize]= src[x + y*linesize];

-        }

-    }

+    w    = end_x - start_x;

+    src += start_y*linesize + start_x;

+    buf += start_x;

     //top

     for(y=0; y<start_y; y++){

-        for(x=start_x; x<end_x; x++){

-            buf[x + y*linesize]= buf[x + start_y*linesize];

-        }

+        memcpy(buf, src, w);

+        buf += linesize;

+    }

+

+    // copy existing part

+    for(; y<end_y; y++){

+        memcpy(buf, src, w);

+        src += linesize;

+        buf += linesize;

     }

     //bottom

-    for(y=end_y; y<block_h; y++){

-        for(x=start_x; x<end_x; x++){

-            buf[x + y*linesize]= buf[x + (end_y-1)*linesize];

-        }

+    src -= linesize;

+    for(; y<block_h; y++){

+        memcpy(buf, src, w);

+        buf += linesize;

     }

-    for(y=0; y<block_h; y++){

+    buf -= block_h * linesize + start_x;

+    while (block_h--){

        //left

         for(x=0; x<start_x; x++){

-            buf[x + y*linesize]= buf[start_x + y*linesize];

+            buf[x] = buf[start_x];

         }

        //right

         for(x=end_x; x<block_w; x++){

-            buf[x + y*linesize]= buf[end_x - 1 + y*linesize];

+            buf[x] = buf[end_x - 1];

         }

+        buf += linesize;

     }

 }