diff --git a/inc/rk_mpi.h b/inc/rk_mpi.h
index 682be05b..c1b344d4 100644
--- a/inc/rk_mpi.h
+++ b/inc/rk_mpi.h
@@ -66,13 +66,13 @@ typedef enum {
     MPP_HAL_CMD_BASE                    = 0x10000,
 
     MPP_OSAL_CMD_BASE                   = 0x20000,
-    MPP_OSAL_SET_VPUMEM_CONTEXT,
 
     MPP_CODEC_CMD_BASE                  = 0x30000,
     MPP_CODEC_INFO_CHANGE,
     MPP_CODEC_SET_DEFAULT_WIDTH_HEIGH,
 
     MPP_DEC_CMD_BASE                    = 0x40000,
+    MPP_DEC_SET_EXT_BUF_GROUP,          /* IMPORTANT: set external buffer group to mpp decoder */
     MPP_DEC_USE_PRESENT_TIME_ORDER,
     MPP_DEC_SET_VC1_EXTRA_DATA,
     MPP_DEC_SET_VP6_ID,
diff --git a/mpp/mpi.cpp b/mpp/mpi.cpp
index 8b412e83..832ec00e 100644
--- a/mpp/mpi.cpp
+++ b/mpp/mpi.cpp
@@ -136,10 +136,18 @@ static MPP_RET mpi_flush(MppCtx ctx)
 
 static MPP_RET mpi_control(MppCtx ctx, MpiCmd cmd, MppParam param)
 {
-    (void)ctx;
-    (void)cmd;
-    (void)param;
     MPI_FUNCTION_ENTER();
+    MpiImpl *p = (MpiImpl *)ctx;
+    switch (cmd) {
+        case MPP_DEC_SET_EXT_BUF_GROUP: {
+            mpp_log("mpi_control group %p", param);
+            p->ctx->mFrameGroup = (MppBufferGroup)param;
+            break;
+        }
+        default: {
+            break;
+        }
+    }
 
     MPI_FUNCTION_LEAVE();
     return MPP_OK;