Dynamically resizing WordPress images on nginx with ngx_http_image_filter_module

Ever notice that image galleries on WordPress.com load faster than those on your own? WordPress.com can serve dynamically-resized images on-the-fly to improve page load speeds and create pretty-looking image galleries. You can achieve this on your own server too, with a few simple tricks in your nginx.conf, taking advantage of URL parameters WordPress appends to image uploads and the nginx libgd-based ngx_http_image_filter_module.

WordPress’ dynamic image sizes serve two main purposes: aside from resizing the source images to a smaller size, it also lets you crop rectangular images to a thumbnail without completely skewing the aspect ratio and butchering the result.

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