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Double-sided Disk
{{unreferenced, date=April 2019 In computer science, a double-sided disk is a disk of which both sides are used to store data. Early floppy disks only used one surface for recording. The term ''single-sided disk'' was not common until the introduction of the double-sided disk, which offered double the capacity in the same physical size. Initially, double-sided disks had to be removed and flipped over to access data on the other side, but eventually devices were made that could read both sides without the need to eject the disk. Manufacturers sold both single-sided and double-sided disks with the double-sided disks being typically 50% more expensive than single-sided disks. While the magnetic-coated medium was coated on both sides, the single-sided floppies had a read-write notch on only one side, thus allowing only one side of the disk to be used. When users discovered this, they began buying the less-expensive single-sided disks and "notching" them using scissors, a hole punch, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Science
Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical disciplines (including the design and implementation of Computer architecture, hardware and Computer programming, software). Computer science is generally considered an area of research, academic research and distinct from computer programming. Algorithms and data structures are central to computer science. The theory of computation concerns abstract models of computation and general classes of computational problem, problems that can be solved using them. The fields of cryptography and computer security involve studying the means for secure communication and for preventing Vulnerability (computing), security vulnerabilities. Computer graphics (computer science), Computer graphics and computational geometry address the generation of images. Progr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Disk Storage
Disk storage (also sometimes called drive storage) is a general category of storage mechanisms where data is recorded by various electronic, magnetic, optical, or mechanical changes to a surface layer of one or more rotating disks. A disk drive is a device implementing such a storage mechanism. Notable types are the hard disk drive (HDD) containing a non-removable disk, the floppy disk drive (FDD) and its removable floppy disk, and various optical disc drives (ODD) and associated optical disc media. (The spelling ''disk'' and ''disc'' are used interchangeably except where trademarks preclude one usage, e.g. the Compact Disc logo. The choice of a particular form is frequently historical, as in IBM's usage of the ''disk'' form beginning in 1956 with the " IBM 350 disk storage unit".) Background Audio information was originally recorded by analog methods (see Sound recording and reproduction). Similarly the first video disc used an analog recording method. In the music indu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Floppy Disk
A floppy disk or floppy diskette (casually referred to as a floppy, or a diskette) is an obsolescent type of disk storage composed of a thin and flexible disk of a magnetic storage medium in a square or nearly square plastic enclosure lined with a fabric that removes dust particles from the spinning disk. Floppy disks store digital data which can be read and written when the disk is inserted into a floppy disk drive (FDD) connected to or inside a computer or other device. The first floppy disks, invented and made by IBM, had a disk diameter of . Subsequently, the 5¼-inch and then the 3½-inch became a ubiquitous form of data storage and transfer into the first years of the 21st century. 3½-inch floppy disks can still be used with an external USB floppy disk drive. USB drives for 5¼-inch, 8-inch, and other-size floppy disks are rare to non-existent. Some individuals and organizations continue to use older equipment to read or transfer data from floppy disks. Floppy disk ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Flippy Disk
The floppy disk is a data storage and transfer medium that was ubiquitous from the mid-1970s well into the 2000s. Besides the 3½-inch and 5¼-inch formats used in IBM PC compatible systems, or the 8-inch format that preceded them, many proprietary floppy disk formats were developed, either using a different disk design or special layout and encoding methods for the data held on the disk. Non-standard media and devices IBM DemiDiskette In the early 1980s, IBM Rochester developed a 4-inch floppy disk drive, the Model 341 and an associated diskette, the DemiDiskette. At about half the size of the original 8-inch floppy disk the name derived from the prefix ''demi'' for "half". This program was driven by aggressive cost goals, but missed the pulse of the industry. The prospective users, both inside and outside IBM, preferred standardization to what by release time were small cost reductions, and were unwilling to retool packaging, interface chips and applications for a propr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Widescreen
Widescreen images are displayed within a set of aspect ratios (relationship of image width to height) used in film, television and computer screens. In film, a widescreen film is any film image with a width-to-height aspect ratio greater than the standard 1.37:1 Academy aspect ratio provided by 35 mm film. For television, the original screen ratio for broadcasts was in fullscreen 4:3 (1.33:1). Largely between the 1990s and early 2000s, at varying paces in different nations, 16:9 (1.78:1) widescreen TV displays came into increasingly common use. They are typically used in conjunction with high-definition television (HDTV) receivers, or Standard-Definition (SD) DVD players and other digital television sources. With computer displays, aspect ratios wider than 4:3 are also referred to as widescreen. Widescreen computer displays were previously made in a 16:10 aspect ratio (e.g. 1680 × 1050), but now are usually 16:9 (e.g. 1920 × 1080). Film History Widescreen was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Letterboxed
Letterboxing is the practice of transferring film shot in a widescreen aspect ratio to standard-width video formats while preserving the film's original aspect ratio. The resulting videographic image has mattes (black bars) above and below it; these mattes are part of each frame of the video signal. LBX and LTBX are identifying abbreviations for films and images thus formatted. Etymology The term refers to the shape of a letter box, a slot in a wall or door through which mail is delivered, being rectangular and wider than it is high. Early home video use The first use of letterbox in consumer video appeared with the RCA Capacitance Electronic Disc (CED) videodisc format. Initially, letterboxing was limited to several key sequences of a film such as opening and closing credits, but was later used for entire films. The first fully letterboxed CED release was '' Amarcord'' in 1984, and several others followed including '' The Long Goodbye'', '' Monty Python and the Holy Grail ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pan And Scan
Pan and scan is a method of adjusting widescreen film images so that they can be shown in fullscreen proportions of a standard-definition 4:3 aspect ratio television screen, often cropping off the sides of the original widescreen image to focus on the composition's most important aspects. Some film directors and enthusiasts disapprove of pan and scan cropping, because it can remove up to 43% of the original image on 2.35:1 films or up to 48% on earlier 2.55:1 presentations, changing the director or cinematographer's original vision and intentions. The most extreme examples remove up to 52% of the original picture on 2.76:1 presentations. The vertical equivalent is known as "tilt and scan" or "reverse pan and scan". The method was most common in the days of VHS, before widescreen home media such as Laserdisc, DVD and Blu-ray. Background For the first several decades of television broadcasting, sets displayed images with a 4:3 aspect ratio, in which the width is 1.33 times the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
LaserDisc
The LaserDisc (LD) is a home video format and the first commercial optical disc storage medium, initially licensed, sold and marketed as DiscoVision, MCA DiscoVision (also known simply as "DiscoVision") in the United States in 1978. Its diameter typically spans . Unlike most optical disc standards, LaserDisc is not fully Digital data, digital, and instead requires the use of analog video signals. Although the format was capable of offering higher-quality video and audio than its consumer rivals—VHS and Betamax videotape—LaserDisc never managed to gain widespread use in North America, largely due to high costs for the players and the inability to record TV programmes. It eventually did gain some traction in that region and became somewhat popular in the 1990s. It was not a popular format in Europe and Australia. By contrast, the format was much more popular in Japan and in the more affluent regions of Southeast Asia, such as Hong Kong, Singapore and Malaysia, and was the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DualDisc
The DualDisc is a type of double-sided optical disc product developed by a group of record companies including MJJ Productions Inc., EMI Music, Universal Music Group, Sony BMG Music Entertainment, Warner Music Group, and 5.1 Entertainment Group and later under the aegis of the Recording Industry Association of America (RIAA). It featured an audio layer intended to be compatible with CD players (but too thin to meet Red Book CD Specifications) on one side and a standard DVD layer on the other. In this respect it was similar to, but distinct from, the DVDplus developed in Europe by Dieter Dierks and covered by European patents. DualDiscs first appeared in the United States in March 2004 as part of a marketing test conducted by the same five record companies who developed the product. The test involved 13 titles being released to a limited number of retailers in the Boston, Massachusetts, and Seattle, Washington, markets. The test marketing was seen as a success after 82% of resp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DVDplus
The DVDplus is a dual-sided disc similar to the DualDisc. It is an optical disc storage technology that combines the technology of DVD and CD in one disc. A DVD and a CD-compatible layer are bonded together to provide a multi-format hybrid disc. DVDplus, like DualDisc, is not a new format as such: it combines two existing formats, DVD and CD, to produce a new product. DVDplus is currently available in three variants: #CD / DVD #CD / DVD-Audio #DVD / ROM These variants can be combined: for example the DVD side can contain a DVD-Video zone, a DVD-Audio zone and a ROM/file download zone, just as is the case with conventional DVDs. It will eventually be possible to produce the DVDplus with upcoming formats, such as Blu-ray. All DVDplus formats can be played both on conventional CD players, on DVD players and on the computer (the format is compatible with approximately 99% of the players on the market). There has been some controvers(See MSNBC article)surrounding the DVDplus format ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compact Disc
The compact disc (CD) is a Digital media, digital optical disc data storage format that was co-developed by Philips and Sony to store and play digital audio recordings. In August 1982, the first compact disc was manufactured. It was then released in October 1982 in Japan and branded as ''Compact Disc Digital Audio, Digital Audio Compact Disc''. The format was later adapted (as CD-ROM) for general-purpose data storage. Several other formats were further derived, including write-once audio and data storage (CD-R), rewritable media (CD-RW), Video CD (VCD), Super Video CD (SVCD), Photo CD, Picture CD, Compact Disc-Interactive (CD-i) and Enhanced Music CD. Standard CDs have a diameter of and are designed to hold up to 74 minutes of uncompressed stereo digital audio or about 650 mebibyte, MiB of data. Capacity is routinely extended to 80 minutes and 700 mebibyte, MiB by arranging data more closely on the same sized disc. The Mini CD has various diameters ranging from ; t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
