BitmapImage and RenderTargetBitmap inherit directly from BitmapSource. The functionality that BitmapImage provides over BitmapSource is just for the convenience of downloading from a URI. I can’t think of any scenario where you will need BitmapImage, and not BitmapSource (which is already RenderTargetBitmap) after you have already uploaded / displayed the image.
What exactly are you trying to do?
Martin harris
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