Win8 App Store - How to get PixelFormat?

Question

In Win8 App Store, given a stream, how can I get the PixelFormat of the image from that stream? I can only get byte array, width, height, stride but I also need pixel format type (like how many bits per pixel, rgba32...) to create some kind of BitmapSource :

//Copy photo from camera to stream
var fPhotoStream = new InMemoryRandomAccessStream();
await mediaCaptureMgr.CapturePhotoToStreamAsync(ImageEncodingProperties.CreateJpeg(), fPhotoStream);
await fPhotoStream.FlushAsync();
fPhotoStream.Seek(0);

//Convert stream to byte array
byte[] bytes = new byte[fPhotoStream.Size];
await fPhotoStream.ReadAsync(bytes.AsBuffer(), (uint)fPhotoStream.Size, InputStreamOptions.None); 

//Get pointer to byte array
GCHandle pinnedArray = GCHandle.Alloc(bytes, GCHandleType.Pinned);
IntPtr pointer = pinnedArray.AddrOfPinnedObject();

//Get image width, height, stride
BitmapImage bmp = new BitmapImage();
bmp.SetSource(fPhotoStream);            
int imgWidth = bmp.PixelWidth;
int imgHeight = bmp.PixelHeight;
int stride = bmp.Width * 4;

//But how to get image pixel format?
int pixelFormat = ??????

Can I do that?

Answer 1

我发现可以使用BitmapDecoder获取PixelFormat信息： http : //msdn.microsoft.com/zh-cn/library/windows/apps/jj709939.aspx