diff --git a/av1/common/alloccommon.c b/av1/common/alloccommon.c
index b4fff4d..0e23ca2 100644
--- a/av1/common/alloccommon.c
+++ b/av1/common/alloccommon.c
@@ -31,6 +31,38 @@
   return mb_rows * mb_cols;
 }
 
+#if LOOP_FILTER_BITMASK
+static int alloc_loop_filter_mask(AV1_COMMON *cm) {
+  aom_free(cm->lf.lfm);
+  cm->lf.lfm = NULL;
+
+  // Each lfm holds bit masks for all the 4x4 blocks in a max
+  // 64x64 (128x128 for ext_partitions) region.  The stride
+  // and rows are rounded up / truncated to a multiple of 16
+  // (32 for ext_partition).
+  cm->lf.lfm_stride = (cm->mi_cols + (MI_SIZE_64X64 - 1)) >> MIN_MIB_SIZE_LOG2;
+  cm->lf.lfm_num = ((cm->mi_rows + (MI_SIZE_64X64 - 1)) >> MIN_MIB_SIZE_LOG2) *
+                   cm->lf.lfm_stride;
+  cm->lf.lfm =
+      (LoopFilterMask *)aom_calloc(cm->lf.lfm_num, sizeof(*cm->lf.lfm));
+  if (!cm->lf.lfm) return 1;
+
+  unsigned int i;
+  for (i = 0; i < cm->lf.lfm_num; ++i) av1_zero(cm->lf.lfm[i]);
+
+  return 0;
+}
+
+static void free_loop_filter_mask(AV1_COMMON *cm) {
+  if (cm->lf.lfm == NULL) return;
+
+  aom_free(cm->lf.lfm);
+  cm->lf.lfm = NULL;
+  cm->lf.lfm_num = 0;
+  cm->lf.lfm_stride = 0;
+}
+#endif
+
 void av1_set_mb_mi(AV1_COMMON *cm, int width, int height) {
   // Ensure that the decoded width and height are both multiples of
   // 8 luma pixels (note: this may only be a multiple of 4 chroma pixels if
@@ -47,6 +79,10 @@
   cm->mb_cols = (cm->mi_cols + 2) >> 2;
   cm->mb_rows = (cm->mi_rows + 2) >> 2;
   cm->MBs = cm->mb_rows * cm->mb_cols;
+
+#if LOOP_FILTER_BITMASK
+  alloc_loop_filter_mask(cm);
+#endif
 }
 
 void av1_free_ref_frame_buffers(BufferPool *pool) {
@@ -142,29 +178,6 @@
   aom_free_frame_buffer(&cm->rst_frame);
 }
 
-#if LOOP_FILTER_BITMASK
-static int alloc_loop_filter(AV1_COMMON *cm) {
-  aom_free(cm->lf.lfm);
-  cm->lf.lfm = NULL;
-  if (cm->coded_lossless) return 0;
-  // Each lfm holds bit masks for all the 4x4 blocks in a max
-  // 64x64 (128x128 for ext_partitions) region.  The stride
-  // and rows are rounded up / truncated to a multiple of 16
-  // (32 for ext_partition).
-  cm->lf.lfm_stride = (cm->mi_cols + (MI_SIZE_64X64 - 1)) >> MIN_MIB_SIZE_LOG2;
-  cm->lf.lfm_num = ((cm->mi_rows + (MI_SIZE_64X64 - 1)) >> MIN_MIB_SIZE_LOG2) *
-                   cm->lf.lfm_stride;
-  cm->lf.lfm =
-      (LoopFilterMask *)aom_calloc(cm->lf.lfm_num, sizeof(*cm->lf.lfm));
-  if (!cm->lf.lfm) return 1;
-
-  unsigned int i;
-  for (i = 0; i < cm->lf.lfm_num; ++i) av1_zero(cm->lf.lfm[i]);
-
-  return 0;
-}
-#endif  // LOOP_FILTER_BITMASK
-
 void av1_free_above_context_buffers(AV1_COMMON *cm,
                                     int num_free_above_contexts) {
   int i;
@@ -202,11 +215,8 @@
   av1_free_above_context_buffers(cm, cm->num_allocated_above_contexts);
 
 #if LOOP_FILTER_BITMASK
-  aom_free(cm->lf.lfm);
-  cm->lf.lfm = NULL;
-  cm->lf.lfm_num = 0;
-  cm->lf.lfm_stride = 0;
-#endif  // LOOP_FILTER_BITMASK
+  free_loop_filter_mask(cm);
+#endif
 }
 
 int av1_alloc_above_context_buffers(AV1_COMMON *cm,
@@ -263,10 +273,6 @@
     if (cm->alloc_mi(cm, new_mi_size)) goto fail;
   }
 
-#if LOOP_FILTER_BITMASK
-  if (alloc_loop_filter(cm)) goto fail;
-#endif  // LOOP_FILTER_BITMASK
-
   return 0;
 
 fail:
diff --git a/av1/common/enums.h b/av1/common/enums.h
index 47259c2..445d30c 100644
--- a/av1/common/enums.h
+++ b/av1/common/enums.h
@@ -94,7 +94,7 @@
 // TODO(chengchen): Temporal flag serve as experimental flag for WIP
 // bitmask construction.
 // Shall be removed when bitmask code is completely checkedin
-#define LOOP_FILTER_BITMASK 0
+#define LOOP_FILTER_BITMASK 1
 
 #define PROFILE_BITS 3
 // The following three profiles are currently defined.
diff --git a/av1/encoder/picklpf.c b/av1/encoder/picklpf.c
index 2285d34..66f42fa 100644
--- a/av1/encoder/picklpf.c
+++ b/av1/encoder/picklpf.c
@@ -67,6 +67,12 @@
     case 2: cm->lf.filter_level_v = filter_level[0]; break;
   }
 
+      // TODO(any): please enable multi-thread and remove the flag when loop
+      // filter mask is compatible with multi-thread.
+#if LOOP_FILTER_BITMASK
+  av1_loop_filter_frame(cm->frame_to_show, cm, &cpi->td.mb.e_mbd, plane,
+                        plane + 1, partial_frame);
+#else
   if (cpi->num_workers > 1)
     av1_loop_filter_frame_mt(cm->frame_to_show, cm, &cpi->td.mb.e_mbd, plane,
                              plane + 1, partial_frame, cpi->workers,
@@ -74,6 +80,7 @@
   else
     av1_loop_filter_frame(cm->frame_to_show, cm, &cpi->td.mb.e_mbd, plane,
                           plane + 1, partial_frame);
+#endif
 
   int highbd = 0;
   highbd = cm->use_highbitdepth;