Fix the picture-in-picture scene bug

Author: qinhui

iOS/APIExample/APIExample/Examples/Advanced/PictureInPicture/PixelBufferPIPViewController/PixelBufferPIPViewController.swift

@@ -256,9 +256,14 @@ extension PixelBufferPIPViewController: AgoraVideoFrameDelegate {
 
     func onRenderVideoFrame(_ videoFrame: AgoraOutputVideoFrame, uid: UInt, channelId: String) -> Bool {
         if let view = displayViews.allObjects.first(where: { $0.uid == uid }) {
-            view.renderFromVideoFrameData(videoData: videoFrame, uid: Int(uid))
+            if let pixelBuffer = videoFrame.pixelBuffer {
+                view.renderVideoPixelBuffer(pixelBuffer: pixelBuffer, width: videoFrame.width, height: videoFrame.height)
+            } else {
+                view.renderFromVideoFrameData(videoData: videoFrame, uid: Int(uid))
+            }
         }
 
         return true
     }
+
 }