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DIPOL Weekly Review - TV and SAT TV, CCTV, WLAN
No. 19/2008 (May 19, 2008)
IFSEC 2008 in Birmingham - a new revolution. The International Fire &Security Exhibition and Conference (IFSEC) in Birmingham that closed last week has confirmed revolutionary changes in the leading ideas of video surveillance.
The main pillars seem to be: use of megapixel cameras, implementation of MPEG-4 compression with H.264 codec, image analysis.
The result of employing these new technologies is, first of all, reduction of the surveillance staff, but also possibility of using professional monitoring center for many locations and automation of alarm procedures.
It marks the end of the era of speed dome cameras. They require individual control, their cooperation with image analysis software is very difficult, and they "loose" in zoom mode a lot of information out of the observed area (usually it is the main drawback).
Megapixel cameras are free of above disadvantages. Suitable system architecture, dual streaming function, and better parameters of transmission (thanks to use of H.264 compression), allow to solve the problem of distributing large data streams, typical for megapixel cameras.
Popularity of IP cameras creates new possibilities for programmers. They work on implementations of systems resistant to various interferences (causing false alarms), capable of: detecting left objects, tracking moving objects, recognizing people, identifying license plates, analyzing persons/objects that are a long time in the field of view, detecting fire, counting people, analyzing traffic flow, analyzing action (scuffles etc.), monitoring flow of crowds of people (at stadiums etc.), analyzing behavior of people observing an object (exhibitions, shop windows etc).
Sony blazes a trail: Go Mega
Transition state in development of television. Digital television replaces analog systems. In th case of satellite broadcasts the process has been concluded, now the migration takes place in terrestrial TV systems.
It should be emphasized that digital television does not mean high definition (HD) itself. In the case of satellite broadcasts, there are available a large number of PAL-resolution programs, but only sparse HD programs. In the instance of terrestrial TV, only several European countries have developed strategies for implementing HD platform. The leaders are France, Great Britain, Estonia. In Poland, a schedule of transition from analog TV to digital TV will be announced by telecommunication regulatory authority, UKE, in June.
What does digitalization mean in practice? Analog signals are susceptible to various interferences. The interferences do not affect digital transmission. Among others, it means elimination of "ghosts" that occur in analog TV as the result of signal reflections from hills, buildings etc. Digital signals are practically insensitive to reflections.
Digital transmission has error correction mechanisms. Some errors can be eliminated in the receiver, due to redundant coding of the signal.
To send audio-video signal digitally, it has to be digitalized and compressed. The first, and still the main compression standard used in satellite broadcasting is MPEG-2. The data streams are received and decoded by typical satellite receivers, e.g. FERGUSON 6600 A99235. The newer MPEG-4 is used as the main standard for HD transmissions (e.g. Polish platform "n").
An important issue is also the kind of modulation used. Most of satellite broadcasts utilize QPSK modulation, the mentioned "n" platform uses 8PSK ("n"), it is also expected implementation of 16PS. The more efficient modulations with higher bitrates require adequately high C/N ratio.

More efficient codecs and modulations allow to send more information in the same channel. It means possibility of resolution improvement - a free space for HD transmissions.
In 2005, JVC presented the first HDTV 1080p television. In 2006, there were more than ten manufacturers of such TV sets, including Samsung. But it will take a lot of time, especially in Europe, one gets possibility of receiving Full HD broadcasts. 1080p (progressive scan) is HDTV standard providing much better picture quality than 1080i (interlaced - alternate displaying of odd and even lines).

SATakademy - kopalnia wiedzy o instalacjach satelitarnych.
PiXORD P463DW - IP speed dome camera for offices, stores, developments.
IP Speed Dome Camera: PiXORD P463DW
IP speed dome camera PiXORD P463DW K1236
ULTIMAX - DVRs for demanding customers - configuring motion detection with Remote Client program. Configuration of motion detection utility in ULTIMAX DVRs can be performed directly with the DVR's keyboard or via Remote Client program, included with each DVR. The program is installed on a computer running Windows XP. It enables the user to setup detection parameters step by step:
  • choose the camera to be configured,
  • mark the motion detection area,
  • set sensitivity level,
  • set the schedule of recording (the periods of time when motion detection triggers recording),
  • assign the channels (cameras) that are to be recorded,
  • assign the alarm outputs that are to be activated,
  • activate OSD info and Remote Client call.
Setting motion detection areas.
ULTIMAX Remote Client program.
Setting motion detection schedule.
ULTIMAX Remote Client program.
Motion detection link - assigning channels to be recorded and alarm outputs to be activated.
ULTIMAX Remote Client program.
The advantage of SATA over IDE. Most of DVRs available on the market are prepared for cooperation with IDE hard discs. However, the newest models are equipped with SATA interfaces. SATA interface provides:
  • higher maximum data transfers: SATA2 - 3000 Mbps, IDE - 1064 Mbps (133 MB/s),
  • possibility of using Hot-Swap discs (ideal for backup, no break in system operation),
  • better ventilation inside DVR (SATA cable is slimmer and can be easily tidied up).
SATA drives have better mechanisms of error detection and correction. Due to monopoly of SATA HDDs for larger capacities, the manufacturers of DVRs launch new models with SATA interfaces. ULTIMAX DVRs of 700 and 500 series and the 316 model are equipped with SATA II buses. The 304 and 308 models will be soon available with SATA II interface, too.
Operational requirements for CCTV systems - part 1. The British Home Office has issued a number of documents on CCTV systems being an important tool in the Government's crime-fighting strategy. The United Kingdom is generally recognised as a leading user CCTV for community safety and crime investigation purposes. There has been developed set of functional requirements for effective use of CCTV footage for evidential purposes in the Criminal Justice System (CJS) and for the needs of the Court Service. An important part of these requirements are technical standards and all aspects of equipment selection.
What is the optimal resolution? Which compression should be chosen for video transmission and recording? What is the sufficient recording speed (frame rate)? It depends on the functional requirements:
  • Areas of concern - what is to be monitored, with what resolution, and with what equipment (cameras, lenses, lighting).
  • Image quality required on the recorded image (choice of DVR).
  • Time synchronization of all system components.
  • Storage capacity (how long is the video retained on the system before being overwritten; the priority is always the required quality level - the capacity has to be adjusted to the retention time).
DHCP server is used for automatic assignment of IP addresses and their configuration for the local network. Due to this service, such parameters like: IP of the computer, the subnet mask, default gateway, and DNS are assigned without any intervention of the user into NIC settings. DHCP service is very convenient in home, office, any IP network - the devices can be added to the network with minimal or no manual configurations. Routers usually support DHCP protocol by default. The local computers, after setting DHCP mode, should be automatically connected to the network. The DHCP server can be also configured according to specific requirements:
  • longer or shorter address lease time,
  • start and end IP address,
  • assignment of static IP addresses for some devices,
  • list of allowed/forbidden MAC addresses etc.

In the case of TP-Link routers this function can be found in DHCP >> DHCP Settings.
Example configuration of DHCP server

We have written about:

9-cable system - multiswitch installations. The most flexible multiswitch installations in multi-story buildings are based on 9-cable system (signals from two Quatro LNBs and terrestrial TV antenna). On each floor we employ the splitter providing signals to multiswitches. It allows to shape the network according to actual requirements - we may deploy practically unlimited number of outlets...
- archive DWR of Jan. 14, 2008

Remote monitoring via the Web. Easy access to the Internet allows to distribute in the Web both live and archived video. Many users have access over ADSL links, without static IP addresses. In this case, to operate video servers it is indispensable to use DDNS service...
- archive DWR of Jan. 14, 2008

How does DDNS work? Users of ADSL service (e.g. Neostrada in Poland) do not have a static IP - it is changed periodically. With this type of connectivity it is not possible to run a server, because the current IP address is unknown...
- archive DWR of Dec. 17, 2007

Index of published issues
24-hour relay race. Like every year, DIPOL will be actively involved in Flower Run (website in Polish). Kwietny Bieg to sztafeta dla wszystkich chętnych, którzy chcą podjąć to wyzwanie, być może najdłuższa i najliczniejsza sztafeta świata. Odbywa sie co roku na przełomie maja i czerwca. Rozgrywa sie w dwóch biegach - dookoła Polski i wokół krakowskich Błoń.
 
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