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Contextual Image Delivery

When developing a mobile version of your Web site, you may want to serve cropped, scaled-down or otherwise transformed versions of the images on your Web server. Contextual Image Delivery lets you construct URLs that transform images server-side at request time, and serve the transformed images to the client.

Using Contextual Image Delivery improves your mobile Web site in several ways:
Image dimensions suited to client screen size
Serving an image of the same dimensions as those served on the regular personal computer version of the Web site to the mobile version typically results in a bad user experience. By using the information provided by the Context Engine, you can discover client screen size and adjust your images' dimensions accordingly.
Performance
While it is possible to perform scaling, cropping and other transformations client-side, this still means serving the original large image. Images are typically the greatest contributors to page weight, so serving original, large images slows down the mobile version of your site.