Wednesday, August 21, 2019
Different Raster Systems With Resolutions
Different Raster Systems With Resolutions Consider three different raster systems with resolutiuns of 640 by 480, 1280 by 1024, and 2560 by 2048. What size frame buffer in bytes is needed for each of these systems to store 12 bits per pixel? How, much storage: is required for each system if 24 bits per pixel are to be stored? Solution:- For 12 bits per pixel:- Frame buffer size=640* 480*12=3686400/8=460800bytes Frame buffer size=1280*1024*12=15728640/8=1966080 bytes Frame buffer size=2560*2048*12=62914560/8=7864320 bytes For 24 bits per pixel:- Frame buffer size=640*480*24=7372800/8 =921600bytes Frame buffer size=1280*1024*24=31457280bits=3932160 bytes Frame buffer size=2560*2048*24=125829120 bits=15728640 bytes Suppose an RGB raster system is to be designed using an 8-inch by 10-inch screen with a resolution of 100 pixels per inch in each direction. If we want to store 6 bits per pixel in the frame buffer, how much storage ( in bytes ) do we need for the frame buffer? Storage to store 6 bits per pixels=8*10*100*6=6000bytes How long would it take to load a 640 by 480 frame buffer with 12 bits per pixel, if lo5 bits can be transferred per second! How long would it take to load a 24-bit per pixel frame buffer with a resolution of 1280 by 1024 using this same transfer rate? For 12 bits per pixel:- Time taken=640*480*12=(3686400)/10^5=36.864 second For 24 bits per pixel:- Time taken=(1280*1024*24)/10^5=314.57second Consider two raster systems with resolutions of 640 by 480 and 1280 by 1024. How many pixels could be accessed per second in each of these systems by a display controller that refreshes the screen at a rate of 60 frames per second? What is the access time per pixel in each system? For resolution 640 by 480 Total pixels=640*480*60=18432000 pixels Time taken=1/18432000=5.425*10^-8 seconds For resolution 1280 by 1024 Total pixels =1280*1024*60=78643200 pixels Time taken =1/78643200=1.27*10^-8 seconds How much time is spent scanning across each row of pixels during screen refresh on a raster system with a resolution of 1280 by 1024 and refresh rate of 60 frames per second? 1024*60=61440rows Time taken =1/61440=1.628^-5seconds Section B Wide-Screen displays Widescreen usually refers to the aspect ratio of an image. In general terms, most images are considered to be in widescreen format when they have an aspect ratio larger than 4:3. When talking about widescreen, generally, most people are referring to the aspect ratio or shape of their TV set, monitor or digital image. One of the best ways to understand widescreen is to compare it with the most common type of aspect ratio, 4:3 which is the aspect ratio or shape of a standard TV set. A standard TV set is pretty much boxy in shape. The aspect ratio is 4:3, this means that the TV screen is 4 times wide by three times high. Because this ratio is almost equal to each other, it is considered similar to a box or square. A perfect square would be 4:4, which is really a ratio that is to 1:1. So now that we know that a standard TV is boxy or squares in shape having an aspect ratio of 4:3, widescreen formats usually have 16:9, a much more rectangular shape. A rectangular is a much more natural looking image. When the human eye sees the world, it does not see a box, but mainly a panorama image. We might focus our attention on a square shape in front of us, but there is a lot more visual information that our peripheral vision picks up. 16:9 aspect ratio is considered widescreen format and is much more natural to view. Most cinematic films are an aspect ratio of 16:9, so they can be viewed easily on a widescreen TV or monitor. You might not have realized that when you watch a movie on your standard TV that has an aspect ratio of 4:3, part of the sides of the movie are cut off or cropped. When you watch a movie on a widescreen, you are able to see the entire picture without any cropping. Sometimes widescreen is referred to by the term letterbox meaning a rectangular shape. Wide screen TV:- When television was introduced and for many years since then the aspect ratio was 4:3. The original standard aspect ratio for films was 4:3 , the adoption of the Academy ratio 1932 brought a slight change to a 1.37 aspect ratio. Material which was originally widescreen (e.g., Cinemascope films) were often transmitted with the sides truncated, using a technique called pan and scan. The introduction of a wider television format was met with some resistance within the film industry, but eventually became the norm. In Europe the PAL TV format, with its higher number of visible screen lines means that the low horizontal resolution associated with showing un cropped widescreen movies on TV is not as bad There is even an extension to PAL, called PAL plus, which allows specially equipped receivers to receive a PAL picture as true 16:9 with full 576 lines of vertical resolution, provided the stations employ the same system. Standard PAL receivers will receive such a broadcast as a 16:9 image letterboxed to 4:3, with a small amount of color noise in the black bars; this noise is actually the additional lines which are hidden inside the color signal. This system has no equivalent in analog NTSC broadcasting. Despite the existence of PALplus and support for widescreen in the DVB-based digital satellite, terrestrial and cable broadcasts in use across Europe, only Belgium, Ireland, the Netherlands, Austria, Germany, Scandinavia and the UK have taken up widescreen at any great rate, with over half of all widescreen channels available by satellite in Europe targeting those areas. 16:9 TV displays have come into wide use. They are typically used in conjunction with Digital, High-Definition Television (HDTV) receivers, or Standard-Definition DVD players and other digital television sources. Digital material is provided to widescreen TVs either in high-definition format, which is natively 16:9 , or as an anamorphically-compressedstandard-definition picture. Typically, devices decoding Digital Standard-Definition pictures can be programmed to provide anamorphic widescreen formatting, for 16:9 sets, and formatting for 4:3 sets. Pan-and-scan mode can be used on 4:3 if the producers of the material have included the necessary panning data; if this data is absent, letterboxing or centre cut-out is used. HD DVD and Blu-ray disc players were introduced in 2006. Toshiba ceased production of HD DVD players in early 2008 after key defections from the HD DVD camp damaged the viability of the format. As of 2010 it still remains to be seen whether Blu-ray will stimulate the sales of HD pre-recorded films on disc, and more HD monitors and tuners. Consumer camcorders are also available in HD-video format at fairly low prices. These developments will result in more options for viewing widescreen images on television monitors. Widescreen Computer Displays Computer displays with aspect ratios wider than 4:3 are also called widescreen. Widescreen computer displays are mainly intended for computers used, at least sometimes, to display entertainment; data processing tends to use 4:3. Widescreen computer displays are typically of the 1.6 (8:5, typically written as 16:10) aspect ratio. True widescreen (16:9) monitors can be found in resolutions of 1024576, 1152648, 1280720, 1600900, and 19201080. Apples 27 iMac introduced a new 16:9 resolution: 25601440 in late 2009. By 2010 many manufacturers had practically abandoned the older 4:3 format, instead opting to manufacture 16:10 models, and lately, even shorter 16:9 displays. Suitability for applications Since many modern DVDs and some TV shows are in a widescreen format, widescreen displays are optimal for their playback on a computer. 16:9 material on a 16:10 display will be letterboxed, but only slightly. However, when screen width is not an issue, as in data processing or viewing 4:3 entertainment material such as older films and digitalphotographs, the sides of the widescreen image may be wasted, although it can be useful to display two or more windows side-by-side.. Most non-linear digital video editing software benefits more from horizontal space than from vertical space. However, for data processing many computer programs often have many toolbars and other information such as status bars, headers, and tabs, which require vertical space. In such cases the additional width is unwanted; on a computer used only for data-processing the additional screen area is better dedicated to a larger 4:3 screen. When displaying a document or ebook, two pages can be displayed side by side on a wide screen, or two documents compared. If a desktop monitor supports it, a whole single page of a book or document can be displayed on a rotated portrait-oriented screen. A very few computer games, including the first few Command Conquer games, run at a native 640400 resolution, making them exceptionally well-suited to 8:5 monitors. A slightly larger number, including Doom 3, can be set to either widescreen or full screen (4:3), with the widescreen options offering wider horizontal fields of view without sacrificing vertical FOV. However, most computer games are not designed for optimum effect on a widescreen display, being stretched unnaturally, not filling the screen, or letterboxed. Older laptop computers with a pointing device that did not take up space such as a pointing stick (Trackpoint) or trackball attached to the side of the machine could accommodate a keyboard which matched a 16:9 screen well. The use of touchpads, which require a lot of space below the keyboard, and the removal of keys such as the Numeric keypad more accurately matches the 4:3 ratio of a screen found on smaller net books and laptops. Widescreen Notebook Displays The earliest instance of the widescreen display being installed inside a notebook computer can be traced back to the Sony C1 which displayed a resolution of just 800 x 480. Widescreens made their official entrance in PC notebooks in 2003, although Apple preceded this by offering the 15 widescreen Power Mac. In 2005, the popularity of widescreen notebooks reached a new high with the unveiling of the Thinkpad widescreen Z60 series notebooks. Sonys pioneering widescreen VAIO C1 notebook The question is: Is the widescreen format for everybody? A big part of the answer will depend on what a widescreen notebook or monitor is used to do. Here are some considerations that might help with your decision: 1. Widescreen Notebooks The length and width of a widescreen notebooks screen set it apart from the standard notebook. The average notebook uses an aspect ratio of 4:3 and a resolution of 1024 x 768 pixels. The widescreen notebook breaks with tradition and increases screen size 25% lengthwise for proportions equal to that of the cinema screen or a widescreen LCD TV. 2. Widescreen Display Sizes The Sony C1 may have started it all, but it is by now considered only as a small-sized widescreen notebook, which is anything below 12.1. Currently on offer are 8.9, 10.6, 11.1, 12.1, 13.3, 14, 15.4, and 17 display sizes, with 19 products reportedly in the pipeline. 3. Widescreen Resolutions and their Corresponding Aspect Ratios Here are the common resolutions found in widescreen displays: 800 x 480 Representing an aspect ratio of 10:6, it was seen first in the Sony C1 notebook computer. Although this resolution is very low by todays standards, it was still quite acceptable compared to the 800 x 600 (4:3) resolutions of the time. Although the C1s screen measured only 8.9, it came as a part of the C1s delightfully tight packaging and superb portability. Currently, displays of this resolution are rarely available. 1024 x 600 Also having an aspect ratio of 10:6, it is meant to challenge the mainstream screen with 1024 x 768 resolution. 1280x 768 1280800 The 1280 x 768 resolution representing an aspect ratio of 16:9.5 and the 1280 x 800 resolution representing 16:10 respectively; these are the two most common resolutions used in contemporary 10.6, 12.1, 13.3, 14, 15.4 widescreen displays and can be considered entry-level for widescreen notebook computers. They provide about a 25% increase in onscreen content compared to screens displaying resolutions of 1024 x 768. 1280 x 854 This resolution (16:10.5) was used first in the 15.4 Power Mac notebook computer and adopted later by a limited number of other PC notebooks (mostly sized 154). This resolution has fallen out of favor in recent times. 1366 x 768 This resolution provides a perfect 16:9 aspect ratio and a perfect home for DVD movies and no more annoying black bands above and below the picture. It is currently available in the 11.1 VAIO Type TX widescreen notebook. 1440 x 900 This resolution (16:10) is found in 17 notebooks only, and is positioned as entry level in 17 widescreen notebooks. 1680 x 1050 This is currently the mainstream resolution (also 16:10) for 17 widescreen notebook computer displays. Users will experience a 35% increase in onscreen content compared to the normal 17 screen displaying a resolution of 1280 x 1024. 1920 x 1200 This is the pinnacle for current 17 widescreen notebook displays, and provides a 75% increase in onscreen content when compared to a normal 17 screen of 1280 x 1024 resolution. The resolution is a perfect fit for 1080p and 1080i (1920 x 1080 16:9) HDTV. 4. Benefits of the Widescreen When used for entertainment, a widescreen display is in its element when showing widescreen DVD movies in their intended 16:9 aspect ratio. This means a bigger picture more comfort and less wasted space (less or no black bands on either side of the picture). The widescreen display also makes it easier to edit and view panoramic images and may eliminate troublesome horizontal scrolling altogether. Comparison of different resolutions Another benefit of the widescreen display is evident when it comes to serious work the ability to display two windows side by side and to drag and drop (or copy n paste) data without having to switch between them is priceless. 5. Is the Widescreen Display Perfect? Weve covered a lot of the widescreen displays positive points, but that doesnt mean that there are no drawbacks. Here are some of them: a. The first and most obvious drawback is price, with the widescreen display being quite a bit pricier than the corresponding 4:3 display This is also the reason why widescreen displays are so ubiquitously absent at the entry level price points, though the gap is getting closer. b. The next problem is an issue of mobility, although this really points to notebook sizes 15 and above. It does depend, however, on the design philosophy of the manufacturer some use the desktop replacement mentality and cause their products to be quite large in size and therefore heavier as well. c. Compatibility with applications especially games may be an issue as many games are programmed to be displayed in 4:3 aspect ratio. Depending on your settings, you will experience black bands to the sides of the image, or you may try and stretch the image, which will look uncomfortable in any case. Certainly more and more, if not all, games today are compatible with widescreen display Latest development in widescreen display: Widescreen LCD displays: Barcos LC series of High-Resolution LCD displays has been specifically designed for use in a wide variety of professional applications. The LC family presents crisp, clear and color-accurate images on 42, 47 and 56 screen sizes. Dedicated versions with HD-SDI inputs are available. Featuring some of the most advanced LCD technology available today, Barcos LC series stands for the ultimate in detail. The LC series consists of a 42 and 47 display in native full high definition (19201080 pixels) and a 56 display in quad full high definition (38402160 pixels). Benefits: High brightness High contrast, even in high ambient light environments High resolution and pixel density Frame lock and gunlock functionality Low power consumption Long lifetime Technology used: Plasma screen technology LED technology CRT (cathode ray tube) LCD Plasma screen technology: Flat panel plasma display is the latest display technology and the best way to achieve displays with excellent image quality and large, flat screen sizes that are easily viewable in any environment. Plasma panels are an array of cells, known as pixels, which are composed of three sub pixels, corresponding to the colors red, green, and blue. Gas in the plasma state is used to react with phosphors in each sub pixel to produce colored light (red, green, or blue). These phosphors are the same types used in cathode ray tube (CRT) devices such as televisions and standard computer monitors. You get the rich dynamic colors that you expect. Each sub pixel is individually controlled by advanced electronics to produce over 16 million different colors. All of this means that you get perfect images that are easily viewable in a display that is less than six inches thick. LED technology : There are many consumer advantages to LEDs over incandescent or fluorescent light bulbs. LED lights consume much less energy. They are 300 percent more efficient than a compact fluorescent light (CFL), and 1,000 percent more efficient than an incandescent bulb. They have a very long life, about 50,000 hours of use at 70 percent of their original power. (LEDs dont burn out or flicker, they simply fade.) This works out to eight hours a day for 13 years at 70 percent power. A typical 60-watt incandescent bulb may last about 1,000 hours. LED lighting contains no mercury or other toxins. LEDs emit no ultra violet (UV) light, so they dont attract bugs. They dont generate heat, so they are cool to the touch. They dont generate radio frequency waves, so they dont interfere with radios or television broadcasts. They also are resistant to vibrations and shocks. CRT (cathode ray tube): The Cathode Ray Tube (CRT) is a vacuum tube containing an electron gun (a source of electrons) and a fluorescent screen, with internal or external means to accelerate and deflect the electron beam, used to create images in the form of light emitted from the fluorescent screen. The image may represent electrical waveforms (oscilloscope), pictures (television, computer monitor), radar targets and others.The CRT uses an evacuated glass envelope which is large, deep, heavy, and relatively fragile. LCD (Liquid-crystal display): Liquid-crystal display televisions (LCD TV) are television sets that use LCD technology to produce images. LCD televisions are thinner and lighter than CRTs of similar display size, and are available in much larger sizes. This combination of features made LCDs more practical than CRTs for many roles, and as manufacturing costs fell, their eventual dominance of the television market was all but guaranteed. In 2007, LCD televisions surpassed sales of CRT-based televisions worldwide for the first time, and their sales figures relative to other technologies are accelerating. LCD TVs are quickly displacing the only major competitors in the large-screen market, the plasma display panel and rear-projection television. LCDs are, by far, the most widely produced and sold television technology today, pushing all other technologies into niche roles .
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment
Note: Only a member of this blog may post a comment.