What do scale and inflate do in the ImageMagick file resizer class

I am using ImageMagick via Symfony to resize images in PHP.

The sfThumbnailer class uses 'scale' and 'inflate' parameters to interface with ImageMagick. What do they do and how will they affect my results?

I realise this is a RTM question, but I already have, and the documentation is not clear.

Image Magick Documentation

Symfony Thumbnail Documentation开发者_运维知识库

Thanks.

Scale

Scale maintains aspect ratio. If set, then aspect will be maintained.

Inflate

Inflate tells script to scale image upward if required. I.e. if set true, then it might increase the width or height if the given width and height are bigger than original width and height.