WinJS / WinRT: detect corrupt image file - windows-8

Question

I'm building a Win8/WinJS app that loads pictures from the local pictures library. Everything is generally working fine for loading valid images and displaying them in a list view.
Now I need to detect corrupt images and disable parts of the app for those images.
For example, open a text file and enter some text in it. Save the file as .jpg, which is obviously not going to be a valid jpg image. My app still loads the file because of the .jpg name, but now I need to disable certain parts of the app because the image is corrupt.
Is there a way I can check to see if a given image that I've loaded is a valid image file? To check if it's corrupt or not?
I'm using standard WinRT / WinJS objects like StorageFile, Windows.Storage.Search related objects, etc, to load up my image list based on searches for file types.
I don't need to filter out corrupt images from the search results. I just need to be able to tell if an image is corrupt after someone selects it in a ListView.

Answer 1

One possible solution would be to check the image's width and height properties to determine whether it is valid or not.

Answer 2

Yeah, the contentType property will return whatever the file extension is. The best way I can find it to look at the image properties:
file.properties.getImagePropertiesAsync()
.done(function(imageProps) {
if(imageProps.width === 0 && imageProps.height === 0) {
// I'm probably? likely? invalid.
});

Answer 3

where SelectImagePlaceholder is an Image Control.. =)
StorageFile file;
using (IRandomAccessStream fileStream = await file.OpenAsync(Windows.Storage.FileAccessMode.Read))
{
try
{
// Set the image source to the selected bitmap
BitmapImage bitmapImage = new BitmapImage();
await bitmapImage.SetSourceAsync(fileStream);
SelectImagePlaceholder.Source = bitmapImage;
//SelectImagePlaceholder.HorizontalAlignment = HorizontalAlignment.Center;
//SelectImagePlaceholder.Stretch = Stretch.None;
this.SelectImagePlaceholder.DataContext = file;
_curMedia = file;
}
catch (Exception ex)
{
//code Handle the corrupted or invalid image
}
}