Average Reviews:
(More customer reviews)First, I'll agree that this book is outdated. It was written on the edge of the Dot Com boom, when the entire CCTV industry was still based on analog equipment. This is why I am not giving it the full 5 stars.
Critique of this book:
The previous reviewer complains about the book not discussing digital video servers - but in chapter 8 this book DOES talk about storing video on hard drives and on optical disks. In 1995 optical disks were the most cost effective method of storing video.
The previous reviewer also complains that this book doesn't describe Frames and Fields, and that too is a valid complaint, but one that should not be held against this book due to the time it was published.
This book is meant as an overview for the CCTV professional just starting out in the CCTV industry. It is not meant to be an engineer's handbook on how PAL or NTSC video is constructed, and it does not go into the mathematics of video. Kruegle was not concerned with explaining video Frames or Fields because these concepts were only of interest to CCTV design engineers. Frames and Fields only became important to the layman when explaining to the layman about storage of video in a digital format.
Video servers were not mentioned because in 1995 video servers were rare and costly. In 1995 when this book was published, hard drive storage cost 23 to 24 cents per megabyte. Today (Feb 2005) hard drive storage costs 6 to 7 cents per 100 megabytes. A video storage system that uses 16 cameras would need to store 480 images a second for real-time video. If the average image size were 9 KB, then one day of storage would require 373 GB of storage. In 1995 this storage would have required two hundred twenty seven top of the line 1.6 GB hard drives, and the cost of the hard drives alone would have been over 85 thousand dollars! Compare this to a single 400 GB hard drive today, which would cost a mere $200.
It's no wonder that Kruegle only touched on digital storage. He mentions that the CCTV industry will advance in the digital realm within the "next decade", and boy was he right! But at the time of his writing, all CCTV systems were analog based, and centrally located. Distributed Ethernet based CCTV systems were not practical. (Many people today would argue that they are still not practical.)So what's so good about this book?
Why in the world would anyone want to have this outdated book on his or her bookshelf?
Because the basic concepts of CCTV are still valid! Also because no other book has been written to present such a well thought out overview of CCTV!
This book describes the role of CCTV in protecting property, people and assets, it describes the limitations of CCTV in general, it discusses the lighting needed, and exactly how to determine what lens to use in which situation. It has one of the best descriptions of how to calculate field of view from focal length that I've ever seen. (Recording methods may have changed, but lens technology is still pretty much the same!)
It discusses analog video transmission methods. And even though there is a huge push today to make all video dependant on gigabit Ethernet, there will always be a need for a few feet of 75-ohm coax cable. An understanding of cable impedance and termination will always be essential.
Kruegle's discussion of Pan / Tilt camera systems is still valid today. He explains pan and tilt degrees per second and why it is important to the CCTV professional. His advice on what is required for servicing a dome or P/T system will save installers and maintainers headaches.
The chapters on low light and covert cameras are extremely outdated (with shoebox cameras for covert installations!) but his advice on placement and lenses for these applications is still extremely useful.
The chapters on CCTV use and applications, and on CCTV power sources are still current. There are a lot of books on the market that explain digital video at an engineering level, including compression and digital storage (check out the books by Peter Symes), but for a good layman's explanation of where to install your CCTV system, which lenses to use, and how to make the system friendly to users, this is the book to start with.
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