"--extra-verbose" option for identify

[naoliv]

Hi!

I don't know if it's something interesting to implement, but (from http://bugs.debian.org/508684) can identify have an "--extra-verbose" option? (or something like this)

(read "--extra-verbose" as "displays even more information, all of them if possible", like the number of colors of the image))

Thank you!

[magick]

Computing the number of unique colors in an image is compute intensive, particularly for large images, so an extra option is required:

• identify -define unique=true -verbose myimage.png