diff --git a/mpp/base/mpp_buffer_impl.cpp b/mpp/base/mpp_buffer_impl.cpp
index 16254fca..18e51bfb 100644
--- a/mpp/base/mpp_buffer_impl.cpp
+++ b/mpp/base/mpp_buffer_impl.cpp
@@ -325,7 +325,8 @@ MPP_RET mpp_buffer_ref_dec(MppBufferImpl *buffer, const char* caller)
 
     MPP_RET ret = MPP_OK;
     MppBufferGroupImpl *group = SEARCH_GROUP_BY_ID(buffer->group_id);
-    buffer_group_add_log(group, buffer, BUF_REF_DEC, caller);
+    if (group)
+        buffer_group_add_log(group, buffer, BUF_REF_DEC, caller);
 
     if (buffer->ref_count <= 0) {
         mpp_err_f("found non-positive ref_count %d caller %s\n",
@@ -717,6 +718,8 @@ MppBufferGroupImpl *MppBufferService::get_group_by_id(RK_U32 id)
         }
     }
 
+    mpp_err_f("can not find group with id %d\n", id);
+
     return NULL;
 }
 
diff --git a/mpp/codec/mpp_dec.cpp b/mpp/codec/mpp_dec.cpp
index 181e4f94..a5beef69 100644
--- a/mpp/codec/mpp_dec.cpp
+++ b/mpp/codec/mpp_dec.cpp
@@ -838,9 +838,7 @@ void *mpp_dec_advanced_thread(void *data)
     MppTask mpp_task = NULL;
     MPP_RET ret = MPP_OK;
     MppFrame frame = NULL;
-    MppFrame tmp_frame = NULL;
     MppPacket packet = NULL;
-    mpp_frame_init(&tmp_frame);
 
     while (MPP_THREAD_RUNNING == thd_dec->get_status()) {
         thd_dec->lock();
@@ -915,13 +913,14 @@ void *mpp_dec_advanced_thread(void *data)
                 mpp_hal_hw_start(dec->hal, &pTask->info);
                 mpp_hal_hw_wait(dec->hal, &pTask->info);
 
-                mpp_buf_slot_get_prop(frame_slots, task_dec->output, SLOT_FRAME, &tmp_frame);
-                mpp_frame_set_width(frame, mpp_frame_get_width(tmp_frame));
-                mpp_frame_set_height(frame, mpp_frame_get_height(tmp_frame));
-                mpp_frame_set_hor_stride(frame, mpp_frame_get_hor_stride(tmp_frame));
-                mpp_frame_set_ver_stride(frame, mpp_frame_get_ver_stride(tmp_frame));
-                mpp_frame_set_pts(frame, mpp_frame_get_pts(tmp_frame));
-                mpp_frame_set_fmt(frame, mpp_frame_get_fmt(tmp_frame));
+                MppFrame tmp = NULL;
+                mpp_buf_slot_get_prop(frame_slots, task_dec->output, SLOT_FRAME_PTR, &tmp);
+                mpp_frame_set_width(frame, mpp_frame_get_width(tmp));
+                mpp_frame_set_height(frame, mpp_frame_get_height(tmp));
+                mpp_frame_set_hor_stride(frame, mpp_frame_get_hor_stride(tmp));
+                mpp_frame_set_ver_stride(frame, mpp_frame_get_ver_stride(tmp));
+                mpp_frame_set_pts(frame, mpp_frame_get_pts(tmp));
+                mpp_frame_set_fmt(frame, mpp_frame_get_fmt(tmp));
 
                 mpp_buf_slot_clr_flag(packet_slots, task_dec->input,  SLOT_HAL_INPUT);
                 mpp_buf_slot_clr_flag(frame_slots, task_dec->output, SLOT_HAL_OUTPUT);
@@ -961,11 +960,6 @@ void *mpp_dec_advanced_thread(void *data)
     dec_release_task_in_port(input);
     dec_release_task_in_port(mpp->mOutputPort);
 
-    if (tmp_frame) {
-        mpp_frame_deinit(&tmp_frame);
-        tmp_frame = NULL;
-    }
-
     return NULL;
 }