detecting image-type and dimensions, recommended approach

[gabor]

i need to get the width/height/image_type of a Buffer. this module works great for this, because the returned structure does have a type attribute that i can use. but it is not documented in the README, so i'm a little worried about using it.
could you please document it in the README?

or, if it's not recommended to use the .type attribute, what alternative approach do you recommend?

(i found issue #29 that might be related to this, and that one recommend using other modules to do the file-type detection, but i need both dimensions and file-type, and it seems suboptimal to parse the Buffer twice. also it was 4 years ago, perhaps things have changed since)