Crestron electronic TPS-GA-TPI Manuale Utente

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Isys
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 G-Series Touchpanel Interface 
 
Crestron TPS-GA-TPI
 
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  Isys
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 G-Series Touchpanel Interface: TPS-GA-TPI 
Operations Guide – DOC. 6501 
to its User’s Guide and extensive help information provided with the software. Also 
refer to the help file in VT Pro-e to learn how to use its audio tool, Sound Manager, 
to attach WAV files to an interface project.  
Pre-recorded WAV files for voice prompts and responses are available from 
Crestron. These files can be stored into and programmed for use in the interfaces 
directly or may be edited with the Sound Recorder. For example, the individual files 
can be combined to create custom messages. 
NOTE:  Interface WAV files can be obtained from the Wave LC Library of the 
Crestron FTP site. 
Bit Depth and File Size 
A bit depth refers to the number of memory bits used to store color data for each 
pixel in a raster image. A TPS-GA-TPI raster image consists of a rectangular grid of 
picture elements (pixels). Each pixel uses the same amount of memory to store its 
color data. The amount of memory is called the bit depth of the image.  
Greater bit depths are required to represent finer gradations of color. Increasing bit 
depth necessarily increases file size. A black and white drawing requires only one bit 
per pixel to store all the available color information. Using a 32-bit per pixel bit 
depth for a black and white image increases the file size 32 times, without adding 
anything to the black and white image quality.   
In an 8-bit per pixel system, the associated 8-bits of video memory for every screen 
pixel, contains a value referring to a location in an 8-bit color table. In this way, any 
one of the specific 256 color table locations is assigned to a pixel.  
A 16-bit highcolor system is considered sufficient to provide life-like colors. It is 
encoded using 5-bits to represent red, 5-bits to represent blue, but (since the human 
eye is more sensitive to the color green) 6-bits to represent 64 levels of green. These 
can therefore be combined to provide 65,536 mixed colors (32 x 32 x 64 = 65,536). 
In a 24-bit graphics display, the video memory allocates 24 bits for each pixel on the 
screen, enabling each pixel to take on any one of a possible 16.7 million colors. Each 
24-bit value is composed of 8-bits for red, 8-bits for green, and 8-bits for blue. These 
triplets of 8-bit values are also referred to as the red, green, and blue color planes. A 
24-bit image is actually composed of three component images, which combine to 
create the truecolor picture. The reason this is called truecolor is that this is around 
the maximum number of colors the human eye is able to detect. 
Truecolor images are sometimes represented by a 32-bit value. The extra 8-bits do 
not enhance the precision of the color representation, but act as an alpha channel that 
represents pixel translucency. The 32-bit truecolor has become popular on the 
computer desktop to provide effects such as translucent windows, fading menus, and 
shadows.  
In graphics intensive applications, raising or lowering the color depth of the 
displayed graphics can achieve a balance of performance and quality. Lower color 
depths do not require as much frame buffer memory or display bandwidth, allowing 
them to be generated and displayed more quickly. Increasing color depth results in 
higher color quality at the expense of display speed and responsiveness. By using a 
majority of 8-bit or 16-bit graphics, and holding the 32-bit graphics to a minimum 
(ex. for a family photo, etc.), you can create a sophisticated project that will fit in the 
memory space provided, and have the interface remain very responsive.