Lumia imaging crop filter

Question

Hi so I'm making an app for Windows 10 that requires a user to choose an image and it's going to crop the image to 310*128. I got the file picker code already. But I want to know how to actually crop and save the image and display in image box. I already have the xaml page done

Answer 1

With Lumia Imaging SDK you can both crop the selected image and resize the image. In this answer I assume you actually want to crop, but from the text I could just as well guess you really just want to resize.

For crop, use the CropEffect from Lumia.Imaging.Transforms. Set the CropArea property on it to the object, and then render it. If you are rendering straight to the XAML page I recommend using a SwapChainPanel object in XAML and a SwapChainPanelRenderer to render on it.

Given that you are loading a StorageFile and rendering to a SwapChainPanel your code might look like something like this:

StorageFile file = ...

using (var source = new StorageFileImageSource(file))
using (var crop = new CropEffect(source, new Rect(0, 0, 310, 128))
using (var renderer = new SwapChainPanelRenderer(crop, YourSwapChainPanel))
{
    await renderer.RenderAsync();
}