The warm reception accorded to our original volume made us decide to put out this updated paperback edition so that the book can be more accessible to graduate students.
This paperback edition is essentially identical to the original hardcover one except for the addition of a new chapter (Chapter 7) which reviews the recent advances in two-dimensional transforms and filters, and image restoration and enhancement. One hundred additional references have been evaluated and cited. A few typographic errors in the original edition were corrected.
Because of limitation of space, we can do little more in Chapter 7 than point the reader to the literature. We hope that in-depth treatments of some of the important recent results in picture processing and digital filtering will appear in future volumes of the Springer physics program.