|
Wallpaper (computing)
A wallpaper or background (also known as a desktop background, desktop picture or desktop image on computers) is a digital image (photo, drawing etc.) used as a decorative background of a graphical user interface on the screen of a computer, smartphone or other electronic device. On a computer, wallpapers are generally used on the desktop, while on a mobile phone they serve as the background for the ''home screen''. Though most devices come with a default background image, modern devices usually allow users to manually change the background image. The term " wallpaper" was used in Microsoft Windows before Windows XP (where it is called the "desktop background"), while macOS refers to it as "desktop picture". On older systems which allowed small repeated patterns to be set as background images, the term desktop pattern was used. History The X Window System was one of the earliest systems to include support for an arbitrary image as wallpaper via the xsetroot program, which at l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Monitor Screen Image Simulated
A computer is a machine that can be programmed to carry out sequences of arithmetic or logical operations (computation) automatically. Modern digital electronic computers can perform generic sets of operations known as programs. These programs enable computers to perform a wide range of tasks. A computer system is a nominally complete computer that includes the hardware, operating system (main software), and peripheral equipment needed and used for full operation. This term may also refer to a group of computers that are linked and function together, such as a computer network or computer cluster. A broad range of industrial and consumer products use computers as control systems. Simple special-purpose devices like microwave ovens and remote controls are included, as are factory devices like industrial robots and computer-aided design, as well as general-purpose devices like personal computers and mobile devices like smartphones. Computers power the Internet, whi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xv (software)
xv is a shareware program written by John Bradley to display and modify digital images under the X Window System. While popular in the early 1990s ("XV is widely considered to be the preeminent image viewer for the X Window System"), no official releases have been made since December 1994. Bradley was unable to negotiate the LZW patent licence necessary for encoding the then-popular GIF format. The patent has now expired, so this legal constraint is no longer relevant. Until at least 2000, Bradley collected third-party updates to xv, for example, support for the PNG image format. These were published as source code patches only. Additional patches are still () created and maintained by volunteers. xv can be run from either the command line or through a graphical interface. It distinguishes itself from many other bitmap viewing and editing programs with a very efficient interface in which the user edits just the parameters of a fixed pipeline of processing steps, rather than m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft
Microsoft Corporation is an American multinational technology corporation producing computer software, consumer electronics, personal computers, and related services headquartered at the Microsoft Redmond campus located in Redmond, Washington, United States. Its best-known software products are the Windows line of operating systems, the Microsoft Office suite, and the Internet Explorer and Edge web browsers. Its flagship hardware products are the Xbox video game consoles and the Microsoft Surface lineup of touchscreen personal computers. Microsoft ranked No. 21 in the 2020 Fortune 500 rankings of the largest United States corporations by total revenue; it was the world's largest software maker by revenue as of 2019. It is one of the Big Five American information technology companies, alongside Alphabet, Amazon, Apple, and Meta. Microsoft was founded by Bill Gates and Paul Allen on April 4, 1975, to develop and sell BASIC interpreters for the Altair 8800. I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bliss (image)
''Bliss'', originally titled Bucolic Green Hills, is the default computer wallpaper of Microsoft's Windows XP operating system. It is a virtually unedited photograph of a green hill and blue sky with clouds in the Los Carneros American Viticultural Area of California's Wine Country. Charles O'Rear took the photo in January 1996 and Microsoft bought the rights in 2000. It is estimated that billions of people have seen the picture, possibly making it the most viewed photograph in history. Overview Former ''National Geographic'' photographer Charles O'Rear, a resident of the nearby Napa Valley, took the photo on film with a medium-format Mamiya RZ67 camera while on his way to visit his girlfriend in 1996. While it was widely believed later that the image was manipulated or even created with software such as Adobe Photoshop, O'Rear says it never was. He sold it to Westlight for use as a stock photo titled ''Bucolic Green Hills''.Metadata of Bliss, Windows XP Beta 2 Westlight ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Personal Computer
A personal computer (PC) is a multi-purpose microcomputer whose size, capabilities, and price make it feasible for individual use. Personal computers are intended to be operated directly by an end user, rather than by a computer expert or technician. Unlike large, costly minicomputers and mainframes, time-sharing by many people at the same time is not used with personal computers. Primarily in the late 1970s and 1980s, the term home computer was also used. Institutional or corporate computer owners in the 1960s had to write their own programs to do any useful work with the machines. While personal computer users may develop their own applications, usually these systems run commercial software, free-of-charge software (" freeware"), which is most often proprietary, or free and open-source software, which is provided in "ready-to-run", or binary, form. Software for personal computers is typically developed and distributed independently from the hardware or operating sys ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Beta Release
A software release life cycle is the sum of the stages of development and maturity for a piece of computer software ranging from its initial development to its eventual release, and including updated versions of the released version to help improve the software or fix software bugs still present in the software. There are several models for such a life cycle. A common method is that suggested by Microsoft, which divides software development into five phases: Pre-alpha, Alpha, Beta, Release candidate, and Stable. Pre-alpha refers to all activities performed during the software project before formal testing. The alpha phase generally begins when the software is feature complete but likely to contain several known or unknown bugs. The beta phase generally begins when the software is deemed feature complete, yet likely to contain several known or unknown bugs. Software in the production phase will generally have many more bugs in it than completed software, as well as speed/performan ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Charles Petzold
Charles Petzold (born February 2, 1953) is an American programmer and technical author on Microsoft Windows applications. He is also a Microsoft Most Valuable Professional and was named one of Microsoft's seven Windows Pioneers. Biography He graduated with a Master of Science in Mathematics from Stevens Institute of Technology in 1975. Aside from writing books about Windows programming he has contributed to various magazines about computers. He had an interest in electronic music and in 1977 started building electronic music instruments out of CMOS chips. In 1979, Petzold started building a computer-controlled digital electronic music synthesizer based on the Zilog Z80 microprocessor. This experience of digital circuitry and assembly language programming formed the basis of his book ''Code: The Hidden Language of Computer Hardware and Software''. Petzold purchased a two-diskette IBM PC in 1984 for $5,000. This debt encouraged him to use the PC to earn some revenue so he w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palette (computing)
In computer graphics, a palette is the set of available colors from which an image can be made. In some systems, the palette is fixed by the hardware design, and in others it is dynamic, typically implemented via a color lookup table (CLUT), a correspondence table in which selected colors from a certain color space's color reproduction range are assigned an index, by which they can be referenced. By referencing the colors via an index, which takes less information than needed to describe the actual colors in the color space, this technique aims to reduce data usage, including processing, transfer bandwidth, RAM usage, and storage. Images in which colors are indicated by references to a CLUT are called indexed color images. Description As of 2019, the most common image colorspace in graphics cards is the RGB color model with 8 bits per pixel color depth. Using this technique, 8 bits per pixel are used to describe the luminance level in each of the RGB channels, therefore 24 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dithering
Dither is an intentionally applied form of noise used to randomize quantization error, preventing large-scale patterns such as color banding in images. Dither is routinely used in processing of both digital audio and video data, and is often one of the last stages of mastering audio to a CD. A common use of dither is converting a grayscale image to black and white, such that the density of black dots in the new image approximates the average gray level in the original. Etymology The term ''dither'' was published in books on analog computation and hydraulically controlled guns shortly after World War II. Though he did not use the term ''dither'', the concept of dithering to reduce quantization patterns was first applied by Lawrence G. Roberts in his 1961 MIT master's thesis and 1962 article. By 1964 dither was being used in the modern sense described in this article. The technique was in use at least as early as 1915, though not under the name ''dither''. In digita ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
24-bit Color
In computer architecture, 4-bit integers, or other data units are those that are 4 bits wide. Also, 4-bit central processing unit (CPU) and arithmetic logic unit (ALU) architectures are those that are based on registers, or data buses of that size. Memory addresses (and thus address buses) for 4-bit CPUs are generally much larger than 4-bit (since only 16 memory locations would be very restrictive), such as 12-bit or more, while they could in theory be 8-bit. A group of four bits is also called a nibble and has 24 = 16 possible values. Some of the first microprocessors had a 4-bit word length and were developed around 1970. Traditional (non-quantum) 4-bit computers are by now obsolete, while recent quantum computers are 4-bit, but also based on qubits, such as the IBM Q Experience. See also: Bit slicing#Bit-sliced quantum computers. The first commercial microprocessor was the binary-coded decimal (BCD-based) Intel 4004, developed for calculator applications in 1971; it had a 4 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
8-bit Color
8-bit color graphics are a method of storing image information in a computer's memory or in an image file, so that each pixel is represented by 8 bits (1 byte). The maximum number of colors that can be displayed at any one time is 256 or 28. Color quantization In order to turn a true color 24-bit image into an 8-bit image, the image must go through a process called color quantization. Color quantization is the process of creating a color map for a less color dense image from a more dense image. The simplest form of quantization is to simply assign 3 bits to red, 3 bits to green and 2 bits to blue, as the human eye is less sensitive to blue light. This creates a so called 3-3-2 8-bit color image, arranged like on the following table: Bit 7 6 5 4 3 2 1 0 Data R R R G G G B B This process is sub optimal. There could be different groupings of colors that make evenly spreading the colors out inefficient and likely to misrepresent the actual image. An alternati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BMP File Format
The BMP file format, also known as bitmap image file, device independent bitmap (DIB) file format and bitmap, is a raster graphics image file format used to store bitmap digital images, independently of the display device (such as a graphics adapter), especially on Microsoft Windows and OS/2 operating systems. The BMP file format is capable of storing two-dimensional digital images both monochrome and color, in various color depths, and optionally with data compression, alpha channels, and color profiles. The Windows Metafile (WMF) specification covers the BMP file format. Device-independent bitmaps and the BMP file format Microsoft has defined a particular representation of color bitmaps of different color depths, as an aid to exchanging bitmaps between devices and applications with a variety of internal representations. They called these device-independent bitmaps or DIBs, and the file format for them is called DIB file format or BMP image file format. According to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
