Crop
Crop an image to a given aspect ratio. This argument is given as a crop and (optionally) a keep setting. The values given here will override the preset settings (if present), can be given after every image, and apply only to the preceding image.
crop is given as an aspect ratio in the width:height format.
keep sets which portion of the image to keep; it's the ‘interestingness' setting passed to the libvips smartcrop function. Your options are:
attention- automagically keep parts likely to draw human attention. Defaultentropy- Crop out the parts with the least variation.centerorcentre- Keep the middle part.
Note
Cropping happens before resizing; the preset widths setting is a post-crop value.
More fine-grained control is beyond the scope of this plugin. I'm not writing an image editor here!
Examples
16:91:1 entropy3:2 center