diff --git a/src/util.c b/src/util.c
index aed0cd7..760a094 100644
--- a/src/util.c
+++ b/src/util.c
@@ -100,7 +100,6 @@ int db_usage_map(imdb_t *db, unsigned short int cols)
 int rec_bitmap(imdb_t *db, uint64_t number)
 {
   imdb_rec_t rec;
-  unsigned char *map = NULL;
 
   assert(db != NULL);
   memset(&rec, 0x0, sizeof(imdb_rec_t));
@@ -114,52 +113,44 @@ int rec_bitmap(imdb_t *db, uint64_t number)
     return 0;
   }
 
-  bitmap_unpack(&rec.data[REC_OFF_BM], &map);
-  bitmap_print(map);
+  bitmap_print(&rec.data[REC_OFF_BM]);
 
   return 0;
 }
 
 int rec_diff(imdb_t *db, uint64_t a, uint64_t b, unsigned short int showmap)
 {
-  imdb_rec_t src;
-  imdb_rec_t dst;
+  imdb_rec_t rec;
   float diff = 0.0;
+  unsigned char one[BITMAP_SIZE];
+  unsigned char two[BITMAP_SIZE];
   unsigned char map[BITMAP_SIZE];
 
   assert(db != NULL);
+  memset(&rec, 0x0, sizeof(imdb_rec_t));
 
-  memset(&src, 1, sizeof(imdb_rec_t));
-  memset(&dst, 2, sizeof(imdb_rec_t));
-
-  src.num = a;
-  dst.num = b;
-
-  if (imdb_read_rec(db, &src) < 1)
-    return -1;
-
-  if (!src.data[0]) {
+  rec.num = a;
+  if (imdb_read_rec(db, &rec) < 1) {
     puts("First sample not exists");
     return 0;
   }
+  memcpy(one, &rec.data[REC_OFF_BM], BITMAP_SIZE);
 
-  if (imdb_read_rec(db, &dst) < 1)
-    return -1;
-
-  if (!src.data[0]) {
-    puts("First sample not exists");
+  rec.num = b;
+  if (imdb_read_rec(db, &rec) < 1) {
+    puts("Second sample not exists");
     return 0;
   }
+  memcpy(two, &rec.data[REC_OFF_BM], BITMAP_SIZE);
 
-  if (showmap == 0) {
-    diff  = (float) bitmap_compare(&src.data[REC_OFF_BM], &dst.data[REC_OFF_BM]);
-    diff /= BITMAP_BITS;
-    printf("%.2f%%\n", diff * 100);
+  if (showmap) {
+    bitmap_diffmap(map, one, two);
+    bitmap_print(map);
     return 0;
   }
 
-  bitmap_diffmap(&map[0], &src.data[REC_OFF_BM], &dst.data[REC_OFF_BM]);
-  bitmap_print(map);
+  diff = (float) bitmap_compare(one, two);
+  printf("%.2f%%\n", (diff / BITMAP_BITS) * 100);
 
   return 0;
 }