Win8 App Store - 如何獲得PixelFormat？

Question

在Win8 App Store中，給定一個流，我怎樣才能得到來自該流的圖像的PixelFormat？我只能得到byte array, width, height, stride，但我還需要像素格式類型（例如，有多少位每像素，RGBA32 ...）創建某種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 = ?????? 

我能做到這一點？

Answer 1

我發現我可以使用BitmapDecoder得到的PixelFormat信息： http://msdn.microsoft.com/en-us/library/windows/apps/jj709939.aspx