can do mediacapture with StartPreviewAsync

Author: linnealovespie

Samples/StyleTransfer/AppModel.cs

@@ -23,7 +23,7 @@ public AppModel()
             this._useGPU = true;
             this._modelSource = "candy";
             this._selectedCameraIndex = 0;
-            this._outputMediaCapture = new CaptureElement();
+            this._outputCaptureElement = new CaptureElement();
         }
 
         // Name of the style transfer model to apply to input media
@@ -86,14 +86,15 @@ public VideoFrame OutputFrame
             }
         }
         // MediaSource for transformed media
-        private CaptureElement _outputMediaCapture;
-        public CaptureElement OutputMediaCapture
+        private CaptureElement _outputCaptureElement;
+        public CaptureElement OutputCaptureElement
         {
-            get {
-                if (_outputMediaCapture == null) _outputMediaCapture = new CaptureElement();
-                return _outputMediaCapture; 
+            get
+            {
+                if (_outputCaptureElement == null) _outputCaptureElement = new CaptureElement();
+                return _outputCaptureElement;
             }
-            set { _outputMediaCapture = value; OnPropertyChanged(); }
+            set { _outputCaptureElement = value; OnPropertyChanged(); }
         }
 
         // MediaSource for the input media

Samples/StyleTransfer/AppViewModel.cs

@@ -298,12 +298,33 @@ public async Task ChangeLiveStream()
             try
             {
                 // Check that SCI hasn't < 0 
+                if (_appModel.SelectedCameraIndex < 0) _appModel.SelectedCameraIndex = 0;
                 _selectedMediaFrameSourceGroup = _mediaFrameSourceGroupList[_appModel.SelectedCameraIndex];
 
                 // Create MediaCapture and its settings
+                var settings = new MediaCaptureInitializationSettings
+                {
+                    SourceGroup = _selectedMediaFrameSourceGroup,
+                    PhotoCaptureSource = PhotoCaptureSource.Auto,
+                    MemoryPreference = _appModel.UseGPU ? MediaCaptureMemoryPreference.Auto : MediaCaptureMemoryPreference.Cpu,
+                    StreamingCaptureMode = StreamingCaptureMode.Video
+                };
                 _mediaCapture = new MediaCapture();
-                await _mediaCapture.InitializeAsync();
+                await _mediaCapture.InitializeAsync(settings);
+
+                var capture = new CaptureElement();
+                capture.Source = _mediaCapture;
+                _appModel.OutputCaptureElement = capture;
+
+                videoEffectDefinition = new VideoEffectDefinition(_videoEffectID);
+                videoEffect = await _mediaCapture.AddVideoEffectAsync(videoEffectDefinition, MediaStreamType.VideoPreview);
+                videoEffect.SetProperties(new PropertySet() {
+                    { "Session", m_session},
+                    { "Binding", m_binding },
+                    { "InputImageDescription", m_inputImageDescription },
+                    { "OutputImageDescription", m_outputImageDescription } });
 
+                await _mediaCapture.StartPreviewAsync();
             }
             catch (Exception ex)
             {
@@ -329,12 +350,13 @@ private void StartPreview()
                 return;
             }
 
-            //_appModel.OutputMediaCapture = MediaSource.CreateFromMediaFrameSource(_selectedMediaFrameSource);
+            //_appModel.OutputCaptureElement = MediaSource.CreateFromMediaFrameSource(_selectedMediaFrameSource);
             //_appModel.InputMediaSource = MediaSource.CreateFromMediaFrameSource(_selectedMediaFrameSource);
         }
 
         private async Task LoadModelAsync()
         {
+
             m_session?.Dispose();
 
             StorageFile modelFile = await StorageFile.GetFileFromApplicationUriAsync(new Uri($"ms-appx:///Assets/{_appModel.ModelSource}.onnx"));
@@ -391,10 +413,9 @@ private void CleanupCameraAsync()
             try
             {
                 _mediaCapture?.Dispose();
-                if (_appModel.OutputMediaCapture != null)
+                if (_appModel.OutputCaptureElement != null)
                 {
-                    CaptureElement output = _appModel.OutputMediaCapture;
-                    _appModel.OutputMediaCapture = null;
+                    _appModel.OutputCaptureElement = null;
 
                 }
                 if (videoEffect != null)
@@ -410,6 +431,7 @@ private void CleanupCameraAsync()
             }
         }
 
+
         private void CleanupInputImage()
         {
             try

Samples/StyleTransfer/MainPage.xaml

@@ -139,7 +139,8 @@
 
           <Button
               Name="UIButtonLiveStream"
-              Click="UIButtonLiveStream_Click"
+              Command="{Binding SetMediaSourceCommand}"
+              CommandParameter="LiveStream"
               ToolTipService.ToolTip="Camera preview">
             <Button.Content>
               <SymbolIcon Symbol="Video" />
@@ -222,10 +223,11 @@
           </StackPanel>
         </Viewbox>
 
-        <CaptureElement
+        <ContentControl
             Name="PreviewControl"
-            Source="{Binding CurrentApp.OutputMediaCapture}"
-            Stretch="Uniform" />
+            Width="720"
+            Height="720"
+            Content="{Binding CurrentApp.OutputCaptureElement}" />
 
         <!--  Input image preview  -->
         <Image

Samples/StyleTransfer/MainPage.xaml.cs

@@ -69,7 +69,7 @@ public async void UIButtonLiveStream_Click(object sender, RoutedEventArgs e)
             }
             try
             {
-                PreviewControl.Source = _viewModel._mediaCapture;
+                //PreviewControl.Source = _viewModel._mediaCapture;
 
                 _viewModel.videoEffectDefinition = new VideoEffectDefinition(_viewModel._videoEffectID);
                 _viewModel.videoEffect = await _viewModel._mediaCapture.AddVideoEffectAsync(_viewModel.videoEffectDefinition, MediaStreamType.VideoPreview);