Creating a circle image with the new ImageDecoder

As mentioned in the previous recipe, the ImageDecoder library is a new library introduced in Android P and promises many new and exciting features not available before with the BitmapFactory class. One of those features is the ability to apply effects to the image with a post processor. A post processor is a new helper class allowing you to add custom processing (or manipulation) to an image after it is loaded. Custom processing might include adding a tint to the image, drawing (such as stamps) on top of the image, adding a frame, or in our example making the image round.

In our example, we start with a rectangle image (downloaded from Pixabay.com, which you can see here: https://pixabay.com/en/wallpaper-background-eclipse-1492818/.) We then apply a post processor to create a rounded image, as you can see in this screenshot: 

This is another exciting new feature available in the ImageDecoder library because until now, developers usually turned...