Question

I’ve found the common way to get image metadata in WPF is to create a BitmapFrame object and inspect the Metadata property on it. However I can’t seem to create a BitmapFrame object that fulfills these two requirements:

1. Does not lock the file
2. Does not throw weird, undocumented exceptions when given certain files

Using these lines seems to create the BitmapImage reliably:

BitmapFrame.Create(new Uri(imageName));
BitmapFrame.Create(new Uri(imageName), BitmapCreateOptions.DelayCreation, BitmapCacheOption.None);

However they leave the file locked for an indeterminate amount of time. There is no dispose method on the BitmapFrame as far as I can tell.

This keeps the file from being locked:

BitmapFrame.Create(new Uri(imageName), BitmapCreateOptions.None, BitmapCacheOption.OnLoad);

However on Vista it throws ArgumentExceptions and InvalidOperationExceptions on certain files and on Win7 it throws FileFormatExceptions and IOExceptions. This makes me think that caching the BitmapFrame is unsupported/untested.

Can you get metadata from an image in WPF without leaving a lock on the file for an indeterminate length of time?

Answer 1

Have you tried using a converter approach? For example, my Intuipic application does this. See BitmapFrameConverter for details on loading without locking, and BitmapOrientationConverter for getting at metadata.