Are there known problems with 8.1 MediaCapture InitializeAsync?

Question

My Lumia 920 keeps needing to be soft reset with volume down and power for 15 seconds, as it randomly completely locks up while debugging.
I'm awaiting MediaCapture.IntializeAsync followed by awaiting MediaCapture.StartPreviewAsync
I'm running the developer preview version.  Anyone else run against this, or got it to work successfully?
If it's of any help, occasionally the phone gets into a state where InitializeAsync throws an exception with Hresult 0xE8010014
My initialization CapSettings are:
capSettings
{Windows.Media.Capture.MediaCaptureInitializationSettings}
AudioDeviceId: ""
AudioProcessing: Default
AudioSource: null
MediaCategory: Other
PhotoCaptureSource: Auto
StreamingCaptureMode: Video
VideoDeviceId: "\\\\?\\DISPLAY#QCOM_AVStream#3&2e24c17&0&UID32768#{e5323777-f976-4f5b-9b55-b94699c46e44}\\Front Sensor"
VideoSource: null
I have yesterday's latest WP8.1 preview now installed, and the problem still exists.
The program is particularly prone to locking up the entire phone when re-initializing.
Several times before crashing I've had a green background on the phone that flashed or just got stuck, but I've had the same problem without actually enabling the preview at all, and just initializing.
Anthony Wieser | Wieser Software Ltd |
www.wieser-software.com

Answer 1

I've got a slightly more improved version here,
http://npsoftware.s3.amazonaws.com/cameraui/CameraUI_2.zip
This one doesn't crash anywhere near as much, but it is still really sluggish.  It now sets the capture and preview resolutions to 640x480.  Via the following code,
private struct SetCaptureResolutionResult
public Boolean CaptureSet;
public IMediaEncodingProperties CaptureProps;
public Boolean PreviewSet;
public IMediaEncodingProperties PreviewProps;
private async Task<SetCaptureResolutionResult> SetCaptureResolution(Size iSize)
SetCaptureResolutionResult pCRRResult = new SetCaptureResolutionResult();
System.Collections.Generic.IReadOnlyList<IMediaEncodingProperties> res = cMCeCapture.VideoDeviceController.GetAvailableMediaStreamProperties(MediaStreamType.Photo);
if (res.Count >= 1)
for (int i = 0; i < res.Count; i++)
if (res[i] is ImageEncodingProperties)
ImageEncodingProperties ip = (ImageEncodingProperties)res[i];
if (ip.Width == iSize.Width && ip.Height == iSize.Height)
await cMCeCapture.VideoDeviceController.SetMediaStreamPropertiesAsync(MediaStreamType.Photo, res[i]);
pCRRResult.CaptureSet = true;
pCRRResult.CaptureProps = ip;
break;
else if (res[i] is VideoEncodingProperties)
VideoEncodingProperties vp = (VideoEncodingProperties)res[i];
if (vp.Width == iSize.Width && vp.Height == iSize.Height)
await cMCeCapture.VideoDeviceController.SetMediaStreamPropertiesAsync(MediaStreamType.Photo, res[i]);
pCRRResult.CaptureSet = true;
pCRRResult.CaptureProps = vp;
break;
res = cMCeCapture.VideoDeviceController.GetAvailableMediaStreamProperties(MediaStreamType.VideoPreview);
if (res.Count >= 1)
for (int i = 0; i < res.Count; i++)
if (res[i] is ImageEncodingProperties)
ImageEncodingProperties ip = (ImageEncodingProperties)res[i];
if (ip.Width == iSize.Width && ip.Height == iSize.Height)
await cMCeCapture.VideoDeviceController.SetMediaStreamPropertiesAsync(MediaStreamType.VideoPreview, res[i]);
pCRRResult.PreviewSet = true;
pCRRResult.PreviewProps = ip;
break;
else if (res[i] is VideoEncodingProperties)
VideoEncodingProperties vp = (VideoEncodingProperties)res[i];
if (vp.Width == iSize.Width && vp.Height == iSize.Height)
await cMCeCapture.VideoDeviceController.SetMediaStreamPropertiesAsync(MediaStreamType.VideoPreview, res[i]);
pCRRResult.PreviewSet = true;
pCRRResult.PreviewProps = vp;
break;
return (pCRRResult);
One odd thing to note from this code is that in the emulator it return the resolutions for MediaStreamType.Photo as ImageEncodingProperties, on the phone it returns them as VideoEncodingProperties, why the difference?
Somewhere out there...