修复了canvas无法播放的问题

lib/pages/canvas_player/widgets/canvas_player.dart

@@ -63,7 +63,7 @@ class _VidCanvasPlayerState extends State<VidCanvasPlayer> {
   }
 
   void loadFrame(Uint8List bytes) async {
-    image = await decodeImageFromList(bytes.buffer.asUint8List());
+    image = await decodeImageFromList(bytes);
     setState(() {});
   }
 
@@ -108,7 +108,7 @@ class _VidCanvasPlayerState extends State<VidCanvasPlayer> {
   }
 
   Widget buildFrameView(BuildContext context) {
-    if (frameBytes != null) {
+    if (image != null) {
       // final size = MediaQuery.of(context).size;
       return CustomPaint(
         painter: VidPainter(image: image),