The codebook generator algorithm involves picking three

different codebook centroids ("high utility", "low 
utility" and "closest to the low utility one"). This 
change avoid the corner case of choosing two times the 
same centroid.


git-svn-id: file:///var/local/repositories/ffmpeg/trunk@14340 9553f0bf-9b14-0410-a0b8-cfaf0461ba5b

libavcodec/elbg.c

@@ -299,8 +299,10 @@ static void do_shiftings(elbg_data *elbg)
             if (elbg->utility_inc[elbg->numCB-1] == 0)
                 return;
 
-            idx[1] = get_high_utility_cell(elbg);
             idx[2] = get_closest_codebook(elbg, idx[0]);
+            do {
+                idx[1] = get_high_utility_cell(elbg);
+            } while (idx[1] == idx[0] || idx[1] == idx[2]);
 
             try_shift_candidate(elbg, idx);
         }