diff --git a/dita/RTC-NG/API/rtc_lite_api.dita b/dita/RTC-NG/API/rtc_lite_api.dita
index 86fab1cee76..6967f74af79 100644
--- a/dita/RTC-NG/API/rtc_lite_api.dita
+++ b/dita/RTC-NG/API/rtc_lite_api.dita
@@ -554,15 +554,16 @@
     </section>
     <section>
         <title><apiname keyref="IVideoFrameObserver"/></title>
+        <note type="attention">通过 <xref keyref="onCaptureVideoFrame"/>、<xref keyref="onPreEncodeVideoFrame"/> 和 <xref keyref="onRenderVideoFrame"/> 回调返回的视频数据中，<parmname>alphabuffer</parmname> 为 <codeph><ph keyref="NULL"/></codeph>。</note>
         <ul>
             <li props="native unreal bp"><xref keyref="getMirrorApplied"/></li>
             <li props="native unreal bp"><xref keyref="getObservedFramePosition"/></li>
             <li props="native unreal bp"><xref keyref="getRotationApplied"/></li>
             <li props="native unreal bp"><xref keyref="getVideoFormatPreference"/></li>
             <li props="native unreal bp"><xref keyref="getVideoFrameProcessMode"/></li>
-            <li><xref keyref="onCaptureVideoFrame"/></li>
             <li props="cpp unreal bp"><xref keyref="onFrame_IVideoFrameObserver"/></li>
             <li props="hide"><xref keyref="onMediaPlayerVideoFrame"/></li>
+            <li><xref keyref="onCaptureVideoFrame"/></li>
             <li><xref keyref="onPreEncodeVideoFrame"/></li>
             <li><xref keyref="onRenderVideoFrame"/></li>
         </ul>