Selecting commutation devices
Commutation systems are referred here as the interconnection devices including cables, transformers of audio and video formats (scalers), switches, commutators, and a variety of amplifiers. The composition and configuration of the commutation system is determined by the types of sources and receivers, and the configuration of the entire complex.
In the simplest case a single-channel switch from N inputs into one output is used, where N is the number of sources. And the video switch with the appropriate interface should be selected (in the simplest case, it is common for all sources and receivers). If one or more sources do not have an interface that matches the switch interface, an interface converter (scaler) is installed on the corresponding input. For example, to connect the computer with SVGA output to the system where all the sources and receivers have S-Video a SVGA à S-Video format converter is required. Often, in such cases the application of universal switches with built-in scalers for each input is justified, as it provides more flexible use of the system for its modernization, for example, when replacing one other player with another one with better parameters but with a different interface (Javidi & Okano, 2011; Berbecel, 2003).
The most flexible solution, and in the case of different rooms with receivers the only possible one, is the use of matrix switchers N x K. There are N inputs and K outputs, while the signal from any input can be fed to any or all outputs. The interface of the matrix switcher is selected on based on video receiver interface, and coordination with the sources is the same as with single-channel switches. It should be noted that all video switches also have audio switches with the similar structure. In this case, the audio part works primarily in the “audio after video” mode, that is, when switching the direction of the video signal causes the corresponding transducing of the audio channel. Some models have independent controls for audio and video channels (Javidi & Okano, 2011; Berbecel, 2003).
When building small single-channel systems with up to four sources the control of all the equipment is normally carried out from the front panels of switches and sources. In the case of more complex systems it is necessary to specify the availability of ports, remote control for the selected switches and sources. Usually it is the RS-232, RS-485 or infrared ports that are used when working with standard remote control (Javidi & Okano, 2011).
Selecting control devices
The equipment of control system is selected based on the criteria of convenience and efficiency when dealing with the complex. In the simplest case it consists of a master controller and keypad located in a convenient place to work. The controller is usually installed with switches and sources. If there are several rooms with independent receivers, audio or video (the so-called “zones”), each of them must have a local control unit installed.
Control devices that connect to the host controller, can be of many different types ranging from simple buttons to touch video panels. The latter are most convenient in use, but at the same time the most expensive solutions. When using them, it should be understood that in addition to the electrical connection to the host controller, a lot of work should be done on their programming. And the programming is not so much in linking the logic of operation of all equipment in the complex, but in the meticulous work with low-level protocols to control each individual device. Additionally, it is necessary to develop a simple and user-friendly graphical interface for a specific touch panel. It is important that a vendor should have the control device with related software and the software should be available, as it can be paid (Javidi & Okano, 2011; Berbecel, 2003).
Purpose-based distinction between different types of information display
Plasma and LCD-panels
The great advantage of LCD-videowalls when compared to plasma is the possibility of continuous operation with a static image. Thus, LCD multi-screen monitors can be used as information boards in airports used for information displays in workplaces, i.e. in areas where previously it was impossible to use plasma video walls.
Available configurations for DIBOSS video wall is up to 9×9 panels. The total value of the image gap in two panels is 2.7 cm. Panels have an internal processor that supports the resolution up to 1920×1080. It is controlled via IR remote control (included); the menu is displayed on the panels themselves (Javidi & Okano, 2011).
Vandal-proof LCD-panels ICON ONE. The information display system Icon One is based on LCD-panels 46”, 57” and 82”. City-format for indoor and outdoor installation in a vandal-resistant casing. Each panel has a built-in computer, through which all installed panels can be combined into a single network, regardless of their location. You can simultaneously transmit information on the panels located in different parts of the city, country, etc. The software allows uploading videos and images of any format. Maintenance and control, scheduling shows, on-off schedule can be carried out from a single remote computer. After installing the vandal-proof display Icon One does not require any intervention (Javidi & Okano, 2011).
Vandal-proof LCD-panels VITZE. Large anti-vandal LCD displays VITZE have diagonals of 46”, 57” and 82”. Optionally, the panel can be equipped with an internal PC for independent operation of each display. At the same time, these panels can be easily combined into an Ethernet local area network for remote access to dashboards and controls regardless of their location. Each panel with internal PC has built-in speakers. Vandal-proof casing protects the panel from the mechanical and electromagnetic effects. Such panels provide huge opportunities in the field of advertising. VITZE panels can display information in a slide show form as well as dynamic video with resolution up to 1920×1080. Ability to connect to the network WLAN, LAN allows simultaneous display of information on the monitors on great distances. Advertising campaign can be started simultaneously in different cities, without leaving the office. Excellent image quality is provided in terms of brightness, contrast, resolution. VITZE LCD-panels are also suitable for static image. Minimum operating time is 50,000 hours, which is 5.5 years of twenty-four hour a day use (Javidi & Okano, 2011).
The installation of the panels is quite easy: for the installation of on-floor panel version only the access to the standard (220V) power supply is needed. Installation is possible in almost any location. Mounting options are: floor, wall (including perpendicular to the wall), ceiling, vertical or horizontal mounting (portrait or landscape format).