How to create round images
When you are creating a marketing site with a lot of visual on it very likely that you will need to process images that you need to display.Fortunately, Sitecore provide you with some basic operation that you would need like resize or grayscale image. Moreover it will think for about caching images on server side after processing, so that processing of the image for specific page will happen only once ( for more information about images params see this link ).