An image file (e.g. JPEG, PNG) contains metadata, i.e. information about the image, e.g. which camera model was used, when the picture has been taken or various image regions. Image regions are useful for describing specific areas of the image (e.g. objects, people) or for indicating how the image should be cropped or rotated to best fit a given container.
This WordPress plugin reads such image regions in order to automatically crop images the best possible way, depending on which container they are being displayed in.
The Frameright app can be used to define such image regions and insert them in the metadata of a picture.
When rendering a post or a page, the plugin looks for images that have image region metadata and replaces them with a web component automatically zooming on the best suited image region, effectively doing better than a classical middle-crop.
This plugin is based on Frameright/php-image-metadata-parser, a fork of dchesterton/image, an image metadata parsing library. Many thanks to dchesterton!