tailieunhanh - Lecture Computer graphics: Lecture 6 - Fasih ur Rehman

The following will be discussed in this chapter: Identify and briefly describe various broadband Internet connections, describe the types of Internet access providers, explain the purpose of a Web browser and identify the components of a Web address, describe how to use a search engine to search for information on the Web,. | Computer Graphics Lecture 06 Fasih ur Rehman Last Class Overview of Graphic Systems LED Display Plasma TV Hardcopy Devices Input Devices Human Visual System Today’s Agenda Human Visual System Illusions Ray Tracing Illusions Illusions Illusions Illusions Illusions Pixel Formats 1-bit gray scale—text and other images where intermediate grays are not desired (high resolution required) 8-bit RGB fixed-range color (24 bits total per pixel)—web and email applications, consumer photographs 8- or 10-bit fixed-range RGB (24–30 bits/pixel)—digital interfaces to computer displays; 12- to 14-bit fixed-range RGB (36–42 bits/pixel)—raw camera images for professional photography 16-bit fixed-range RGB (48 bits/pixel)—professional photography and printing, intermediate format for image processing of fixed-range images; 16-bit fixed-range gray scale (16 bits/pixel)—radiology and medical imaging; 16-bit “half-precision” floating-point RGB—HDR images; intermediate format for real-time rendering; 32-bit | Computer Graphics Lecture 06 Fasih ur Rehman Last Class Overview of Graphic Systems LED Display Plasma TV Hardcopy Devices Input Devices Human Visual System Today’s Agenda Human Visual System Illusions Ray Tracing Illusions Illusions Illusions Illusions Illusions Pixel Formats 1-bit gray scale—text and other images where intermediate grays are not desired (high resolution required) 8-bit RGB fixed-range color (24 bits total per pixel)—web and email applications, consumer photographs 8- or 10-bit fixed-range RGB (24–30 bits/pixel)—digital interfaces to computer displays; 12- to 14-bit fixed-range RGB (36–42 bits/pixel)—raw camera images for professional photography 16-bit fixed-range RGB (48 bits/pixel)—professional photography and printing, intermediate format for image processing of fixed-range images; 16-bit fixed-range gray scale (16 bits/pixel)—radiology and medical imaging; 16-bit “half-precision” floating-point RGB—HDR images; intermediate format for real-time rendering; 32-bit floating-point RGB—general-purpose intermediate format for software rendering and processing of HDR images. Image Storage RGB images result in almost 3MB for 1 million pixel image To reduce storage space, various compression techniques are employed and used in image compression. Generally compression is categorized as Lossless Compression Lossy Compression Storage Formats jpeg. This lossy format compresses image blocks based on thresholds in the human visual system. This format works well for natural images. tiff. This format is most commonly used to hold binary images or losslessly compressed 8- or 16-bit RGB although many other options exist. ppm. (Portable Pixel Map)This very simple lossless, uncompressed format is most often used for 8-bit RGB images although many options exist. png. (Portable Network Graphics) This is a set of lossless formats with a good set of open source management tools. Rendering Rendering Rendering Most basic task in graphics. Two types Object Oder .