diff --git a/display/graphic/common/v2_2/BufferHandleMetaKeyType.idl b/display/graphic/common/v2_2/BufferHandleMetaKeyType.idl
index b3d8175dca229559198906bdf8e25ff911730633..409a1a9a50d44b0b2f6ee8d63eca532a59174bfd 100644
--- a/display/graphic/common/v2_2/BufferHandleMetaKeyType.idl
+++ b/display/graphic/common/v2_2/BufferHandleMetaKeyType.idl
@@ -23,10 +23,17 @@
 package ohos.hdi.display.graphic.common.v2_2;
 import ohos.hdi.display.graphic.common.v2_1.BufferHandleMetaKeyType;
 
+enum BufferHandleAttrKey : ohos.hdi.display.graphic.common.v2_1.BufferHandleAttrKey {
+    ATTRKEY_VIDEO_AI_HDR_LUT = 4099,                // value: grid lut for video aihdr
+    ATTRKEY_EXTERNAL_LOWDELAY_INFO = 4100,          // value: ExternalLowDelayInfo
+};
+
 /**
- * @ brief Enumerates buffer handle attribution keys.
+ * @brief ExternalLowDelayInfo of [value] in GetMetadata/SetMetaData, to trans metadata.
  *
+ * @since 6.0
+ * @version 1.0
  */
-enum BufferHandleAttrKey : ohos.hdi.display.graphic.common.v2_1.BufferHandleAttrKey {
-    ATTRKEY_VIDEO_AI_HDR_LUT = 4099,                // value: grid lut for video aihdr
+struct ExternalLowDelayInfo {
+    unsigned int enhanceLayerFlag;                  // enhance layer flag for lowdelay dual420
 };
\ No newline at end of file