on January 4, 2003
This book seems to follow the disappointing (to me at least) model of many engineering texts--that being the reluctance to present new mathematical concepts/techniques. Almost every mathematical concept/technique used in this book was already covered by the prerequisite text by Oppenheim, "Signals and Systems." It would seem that a subject so entrenched with complex numbers and polynomials could be taught in such a manner that would include theorems and concepts from these well-established mathematical disciplines. Note that I did not read the chapter on Hilbert transforms, or the section on the Discrete Cosine Transform, so I cannot comment on them. I did read all other sections. The sections on random signals do introduce new concepts, but they were only put in as a quick review of concepts meant to be studied in a random processes class. On the other hand, this is a very readable book, which has proven very useful. It does present MANY new engineering concepts. If analytic function theory had been introduced, this book probably would not have room left to be as complete a reference for existing introductory DSP theory. However by avoiding the math it has limited the continuing students ability to develop insight into deeper theory, or develop new theory.
on August 8, 2002
I used the author's book "Digital Signal Processing" in my college study, and I also read and cite the 1st Edition of
"Discrete-Time Signal Processing" during my work experience. That's a very good reference. But I don't have the
However, after going through the Table Of Contents of the 2nd Edition of "Discrete-Time Signal Processing", I
think Oppenheim&Schafer did a resaonable tradeoff to reflect state of the art in DSP domain.
They add: Discrete Cosine Transform (DCT) which is mostly used in image compression, Multirate Signal
Processing which is used widely in modern DSP, and Oversampling and Noise Shaping Sampling for A/D and D/A
In consequence, they remove: Lattice Structure, IIR Filters Design, Cepstrum Analysis (often used in speech
signal processing) and Homomorphic Signal Processing, which are a bit sophisticated. And I guess the reason to
remove IIR Filter Dsign is there exists many computer-aided tools on digital filter design, and made this very easy.
on May 26, 2000
I am referring here to the Digital Signal Processing (DSP) that the authors wrote in the 1970's or earlier versus the more recent editions of Discrete-Time Signal Processing (DTSP).
I have both the DSP version and the 1st edition of DTSP, and used them for coursework. From my personal recollection: I tried to take an introductory graduate-level DSP course twice, once with the old DSP text (but did not get to finish), and the second time completing the course from another college with the DTSP text. DSP, in spite of its introductory and pioneering nature, turned out to be the more readable and better organized textbook among the two. It is shorter by many pages, less verbose, less "heavy and circular in arguments", and quicker to come to the point, not to mention being clearer, more lucid, and well-illustrated with good examples and diagrams without overwhelming the reader. The beginning chapters are well written with introduction to the applications of Complex Variables in the context of DSP as an EE subject. In short, DSP by Oppenheim and Schafer is the less ambitious book of the two, but really accomplishes much more by doing less and focusing on the essential concepts underlying DSP.
I can see why and where many beginning EE Signal Processing students tend to get frustrated. DTSP, 1st edition, is actually a rewritten version of DSP, albeit meant to be a major extension (or expansion, if you wish) with more applications appended and "heavier expositions". (This reminds me of many other books by MIT EE faculty on the market.) I find the most frustrating part of DTSP is the chapters on transcending from the Discrete Fourier Transform (DFT) to Fast Fourier Transform (FFT). Why? All you have to do is look at the way the authors present the DFT, then get to understand the truncated DFT, and try to follow the steps that supposedly get one toward FFT's - not at all clear or well-connected conceptually. It is even more obvious when one tries to do the moderately difficult and somewhat tedious exercises at the back of each chapter. While it is true that DTSP appears superficially "precise and rigorous", I find it a bit convoluted and too ambitious in its treatment of digital signal processing topics, indicative of a desire to reflect trappings of the latest applications by demonstrating the power of the theory presented. Why not just return to the fundamentals of DSP and limit the topics to a manageable level, thereby retaining a high degree of visibility for the more average EE student. (Maybe DTSP was meant to be taught by the authors themselves, or by their Ph.D. students. That way, the obscure points, discussions and topics in the textbook could be explained away in live classroom lectures via student interactions. Right?) In spite of all this, I think DTSP has intrinsic value in EE Signal Processing, being that it retained much of the key concepts in the older DSP text with some original flavor.
Suggestion to authors: Write another book on DSP, but limit the book to concepts and some elementary applications, just like the 1970's original, or better still edit and update the original to be published as an inexpensive classic by, say, Dover. Rewrite DTSP as the follow-on textbook. How about it? I really miss the lucid style of the more original DSP textbook by the authors. And I mean it, seriously!
on August 9, 2000
As others have said, this is the DSP bible. I have worked in the field of DSP as a post-grad student, lecturer ("professor") and an R&D engineer for over 10 years now and this book is in my "must-have" collection. It is the book I learnt my DSP from; it is the book I have taught DSP from; it is a very good reference book for the practicioner.
Having said that, I should also point out what I believe this book is not (and why it gets only 4 stars) : it is not a good book for self-learning. If this is what you are after, I recommend Rick Lyons' book "Understanding Digital Signal Processing" (five stars from me).
If you are a mechanical engineer learning DSP, I suggest asking your local Bruel & Kjaer representative if he'll give you a copy of Bob Randall's "Frequency Analysis" published by B&K (ISBN 87 87355 07 8; "only" 3.5 stars, but 4.5 stars if you're a mechanical engineer).
on December 9, 1999
I am currently taking a first course in DSP where O&S is the text used. The text is just plain HELL to read. Explanations are often incomplete. I don't believe my professor had a choice in the selection because the other day he called in incoherent. I recently spoke to a second professor at UT who said he never uses it in his courses because he believes the authors are trying to impress their colleagues with the writing style.
Specific topics covered so far in the course, which are mentioned, but NOT covered in the text: Closed form solution of Difference Equations, complex convolution theorem, unilateral Z-transform and their use in the solution of Difference Equations with non-zero initial conditions, and Contour Integration.
I can see where some people use this as a reference, because there are many brief, accurate statements. But if you're trying to learn this material for the first time, look elsewhere.
on September 21, 2001
This book has its share of shortcomings, but overall, it is probably the best and most complete reference on DSP. Unfortunately, it does skip a few important topics. For example, the second edition threw out the section on designing IIR bandpass and highpass filters from lowpass prototypes. This section used to be in the first edition and is VERY important, so I don't see how Oppenheim & Schafer could have justified throwing it out. They also conspicuously left out filter design based on the frequency sampling method. But in spite of these omissions, it's hard to recommend another book over this one. The one that comes closest is Mitra's.
In the end, if you want to learn DSP and work in the field, you have to have this book, as well as the ones by Mitra, Proakis & Manolakis, Jackson, and, of course, Rabiner & Gold. If you get all those, you'll have the complete reference of CORE DSP texts.
on August 17, 1999
I'm almost an engineer and during my digital signal theory course I found this book exaustive, precise, never approximative. If you want to start learning about DSP theory, read this one even if you'll need some knowledge especially in the field of complex analysys; anyway when you get to the end you'll be able to make filter projects in the same way you drink a glass of water!! The content of the book is well exposed: the author start introducing LTI systems representation, then he explores the Z-transform domain; after that he goes on speaking about A/D and D/A conversion. As far as I'm concerned I found chap 6 (about structures for digital filter) and chap 7 (about filter techniques) extremely interesting and useful. Hey, guys, if you don't have understood yet, this is a MUST
on April 21, 2001
This is probably the most complete reference in DSP. It's full of examples covering the whole stuff in DSP. However this is certainly not fur use as an introductory book because the aim is not the explanation of fundamental concepts in DSP (for that go to Lyons "Understanding Digital Signal Processing"). Maybe it is possible to learn DSP with this book but then as a companion of a good undergrad course, not for self-study.
As stated by another reviewer, this book is over-crowded with developments, details and examples that could be overwhelming to the newcomer. This is probably its biggest drawback, in that its completeness hinders on its readability. So be aware that this is not an easy DSP book, it's THE DSP book.
on September 13, 2000
Although the authors say this book could be used as an introductory text in DSP, it is not. This book is a no nonsense approach towards DSP. You need firm grounding in calculus, signals and systems to be close to even understand what the authors intend to say.
With a good professor and with the skill set that the authors assume you have, you will find this a life long reference. How ever for the not so sure Stanley's Digital Signal processing is a much better choice.
The beginner should find Richard Lyon's Understanding DSP to be more user friendly, but if you outgrow Lyon, then this is the book that would whet your appetite.This book will be one you will frequently refer to clear your doubts.
on June 5, 2001
I found this book to be an excellent fundamental text about DSP. But is it a good introductory book for beginners? Well, it depends... The book covers the essential topics in great depth and that means every one of its 800+ pages is packed with concepts and details and examples. The style is clear, but the amount of information can be a little overwhelming when you read it for the first time. If you have time, patience, a good maths background, the desire to master the subject, and someone to clarify your doubts, this can be the best first book on DSP you could ever buy. If you just want to learn the basics, and don't have much time or patience you should probably look elsewhere.