Some issues however detract from a 5 star rating:
a) The code examples are lame (lots of single letter variables) and poor C idioms, and some silly extra calculations, like counting pixels one at time in a loop when a single multiply would yield the same result.
b)The book feels old even though it was written in 1993. It has a codec for MacPaint files. If this doesn't ring a bell to you, MacPaint was written circa 1985 and it supports two bit images only. Most algorithms are tweaked for the B/W and/or grayscale versions so the reader will have to interpolate/derive her own color versions
C) The descriptions of the algorithms are suboptimal, but heck it is still orders of magnitude more useful than one of the fat texts on the subject. Coupled with the code examples you can easily figure out any non-clear descriptions without having to wade through a giant tome full of pseudo code.
Would I get it again - absolutely. I even made a special place for it (the top of my monitor so it won't get lost).
The theory is not emphasized, so readers should look elsewhere for that information. However, considering its small size, this book offers a lot of very useful information.