Gaming Overview课件.ppt

Image Quality Issues Screen resolution Color Blank space between the pixels Intentional image degradation Brightness Contrast Refresh rate Sensitivity of display to viewing angle 精品文档 Pixels Pixel - The most basic addressable image element in a screen CRT - Color triad (RGB phosphor dots) LCD - Single color element Screen Resolution - measure of number of pixels on a screen (m by n) m - Horizontal screen resolution n - Vertical screen resolution 精品文档 Other meanings of resolution Pitch - Size of a pixel, distance from center to center of individual pixels. Cycles per degree - Addressable elements (pixels) divided by twice the FOV measured in degrees. The human eye can resolve 30 cycles per degree (20/20 Snellen acuity). 精品文档 Color There are no commercially available small pixel technologies that can individually change color. Color is encoded by placing different-colored pixels adjacent to each other. Field sequential color uses red, blue and green liquid crystal shutters to change color in front of a monochrome screen. 精品文档 Video Formats NTSC - 525x480, 30f/s, interlaced PAL - 625x480, 25f/s, interlaced VGA - 640x480, 60f/s, noninterlaced SVGA – 800x600, 60f/s noninterlaced RGB - 3 independent video signals and synchronization signal, vary in resolution and refresh rate Time-multiplexed color - R,G,B one after another on a single signal, vary in resolution and refresh rate 精品文档 Raster Displays Cathode Ray Tubes (CRTs), most “tube” monitors you see. Very common, but big and bulky. Liquid Crystal Displays (LCDs), there are two types transmissive (laptops, those snazzy new flat panel monitors) and reflective (wrist watches). 精品文档 Cathode Ray Tubes (CRTs) Heating element on the yolk. Phosphor coated screen Electrons are boiled off the filament and drawn to the focusing system. The electrons are focused into a beam and “shot” down the cylinder. The deflection plates “aim” the electrons to a specific position on the screen. 精品文档 CRT Phosphor Screen The screen is c