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Wobble Frequency
Optical discs, with the exception of DVD-RAM, have their data encoded on a single spiral, or a ''groove'', which covers the surface of the disc. In the case of recordable media, this spiral contains a slight sinusoidal deviation from a perfect spiral. The period of this sine curve corresponds to the wobble frequency. The wobble frequency is commonly used as a synchronization source to achieve constant linear velocity while writing a disc, but has other uses as well depending on the type of disc. The frequencies quoted all assume that the disc is being written at the '1x' speed. The frequencies are appropriately higher for faster writing speeds. CD-R and CD-RW discs use a frequency modulated wobble of 22.05 kHz to encode information, such as the Absolute Time in Pregroove (ATIP), into the groove. DVD-R and DVD-RW have a constant wobble frequency of 140.6 kHz relying on data 'pits' beside the groove to convey information (Land pre-pit). DVD+R and DVD+RW have a constant w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Optical Discs
An optical disc is a flat, usuallyNon-circular optical discs exist for fashion purposes; see shaped compact disc. disc-shaped object that stores information in the form of physical variations on its surface that can be read with the aid of a beam of light. Optical discs can be reflective, where the light source and detector are on the same side of the disc, or transmissive, where light shines through the disc to be detected on the other side. Optical discs can store analog information (e.g. LaserDisc), digital information (e.g. DVD), or store on the same disc (e.g. CD Video). Their main uses are the distribution of media and data, and long-term archival. Design and technology The encoding material sits atop a thicker substrate (usually polycarbonate) that makes up the bulk of the disc and forms a dust defocusing layer. The encoding pattern follows a continuous, spiral path covering the entire disc surface and extending from the innermost track to the outermost track. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DVD-RW
DVD recordable and DVD rewritable are a collection of optical disc formats that can be written to by a DVD recorder and by computers using a DVD writer. The "recordable" discs are write-once read-many (WORM) media, where as "rewritable" discs are able to be erased and rewritten. Data is written (" burned") to the disc by a laser, rather than the data being "pressed" onto the disc during manufacture, like a DVD-ROM. Pressing is used in mass production, primarily for the distribution of home video. DVD±R (also DVD+/-R, or "DVD plus/dash R") is a shorthand term for both DVD+R and DVD-R formats. Likewise, the term DVD±RW refers to both rewritable disc types, the DVD+RW and the DVD-RW. DVD±R/W (also written as, DVD±R/RW, DVD±R/±RW, DVD+/-RW, DVD±R(W) and other arbitrary ways) handles all common writable disc types, but not DVD-RAM. A drive that supports writing to all these disc types including DVD-RAM (but not necessarily including cartridges or 8cm diameter discs) is refer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Compact Disc
The compact disc (CD) is a Digital media, digital optical disc data storage format co-developed by Philips and Sony to store and play digital audio recordings. It employs the Compact Disc Digital Audio (CD-DA) standard and was capable of holding of uncompressed stereo audio. First released in Japan in October 1982, the CD was the second optical disc format to reach the market, following the larger LaserDisc (LD). In later years, the technology was adapted for computer data storage as CD-ROM and subsequently expanded into various writable and multimedia formats. , over 200 billion CDs (including audio CDs, CD-ROMs, and CD-Rs) had been sold worldwide. Standard CDs have a diameter of and typically hold up to 74 minutes of audio or approximately of data. This was later regularly extended to 80 minutes or by reducing the spacing between data tracks, with some discs unofficially reaching up to 99 minutes or which falls outside established specifications. Smaller variants, such ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Media Identification Code
The Media Identification Code (MID) is used on DVD-R, DVD+R and DVD-RAM discs to identify the manufacturer and to assist the DVD burner to select the best write strategy for the inserted media. The technology is inherited from the ATIP code used on CD-R discs. If the DVD burner recognizes the discs it means that the disc has been tested by the drive manufacturer to achieve the best possible burn using an optimal write strategy. The strategy is stored in the firmware. Writing to a disc with no MID code or a code that is not recognized can result in inaccurate recording and data read-back problems. Displaying the MID The following programs can be used to display the contents of the MID With Windows * instalDVDInfoProby Nic Wilson (full 14-day trial available without any adverts) * instalDVDIdentifierby Kris Schoofs (freeware) With Linux Ubuntu and other Linux systems have dvd+rw-tools installed by default, which provides a command to display the media data: $ dvd+rw-m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Book Type
The book type is a field of four bits at the start of every DVD (in the physical format information section of the control data block) that indicates what the physical format of the disc is. Many devices will use this field to determine how the disc should be treated. One common cause of compatibility problems is the failure of a device to recognize the book type of the disc, most likely because the device had been manufactured before that particular book type was defined; for example, most DVD playback devices made before mid-2004 cannot recognize the relatively new DVD+R DL Book Type. For DVD+R, DVD+RW, and DVD+R DL discs, it is possible to change the book type field value to the value associated with the DVD-ROM format (or in some rare and unorthodox cases, even the value associated with the DVD-R format—though only DVD+R can be changed to this) in order to fool older devices, which is a trick known as ''bitsetting''. These are the possible values of the Book Type Field ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
HD DVD
HD DVD (short for High Density Digital Versatile Disc) is an obsolete high-density optical disc format for storing data and playback of high-definition video.Alternative Uses for your soon to be obsolete HD-DVD Player . Retrieved September 18, 2019.Format Wars Retrieved September 18, 2019.HD DVD owners 'anger' over obsolete players Retrieved September 18, 2019. [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BD-R
Blu-ray Disc Recordable (BD-R) and Blu-ray Disc Recordable Erasable (BD-RE) refer to two direct-to-disk recording, direct to disc optical disc recording technologies that can be recorded on to a Blu-ray-based optical disc with an optical disc recorder. BD-R discs can only be Write once read many, written to once, whereas BD-RE discs can be erased and re-recorded multiple times, similar to CD-R and CD-RW for a compact disc (CD). #Capacity, Disc capacities are 25 gigabyte, GB for single-layer discs, 50 GB for double-layer discs, 100 GB ("BDXL") for triple-layer, and 128 GB ("BDXL") for quadruple-layer (in BD-R only). The minimum speed at which a Blu-ray Disc can be written is 36 megabits (4.5 megabytes) per second. As of 2024, one of the primary pioneers of the Blu-ray disc, Sony, is winding down production of recordable Blu-ray discs in its plant in Tagajō, Japan. Sony plans to gradually cease its manufacturing of optical media, including recordable Blu-ray disc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DVD+RW
DVD recordable and DVD rewritable are a collection of optical disc formats that can be written to by a DVD recorder and by computers using a DVD writer. The "recordable" discs are write-once read-many (WORM) media, where as "rewritable" discs are able to be erased and rewritten. Data is written (" burned") to the disc by a laser, rather than the data being "pressed" onto the disc during manufacture, like a DVD-ROM. Pressing is used in mass production, primarily for the distribution of home video. DVD±R (also DVD+/-R, or "DVD plus/dash R") is a shorthand term for both DVD+R and DVD-R formats. Likewise, the term DVD±RW refers to both rewritable disc types, the DVD+RW and the DVD-RW. DVD±R/W (also written as, DVD±R/RW, DVD±R/±RW, DVD+/-RW, DVD±R(W) and other arbitrary ways) handles all common writable disc types, but not DVD-RAM. A drive that supports writing to all these disc types including DVD-RAM (but not necessarily including cartridges or 8cm diameter discs) is refer ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DVD-R
DVD recordable and DVD rewritable are a collection of optical disc formats that can be written to by a DVD recorder and by computers using a DVD writer. The "recordable" discs are write-once read-many (WORM) media, where as "rewritable" discs are able to be erased and rewritten. Data is written (" burned") to the disc by a laser, rather than the data being "pressed" onto the disc during manufacture, like a DVD-ROM. Pressing is used in mass production, primarily for the distribution of home video. DVD±R (also DVD+/-R, or "DVD plus/dash R") is a shorthand term for both DVD+R and DVD-R formats. Likewise, the term DVD±RW refers to both rewritable disc types, the DVD+RW and the DVD-RW. DVD±R/W (also written as, DVD±R/RW, DVD±R/±RW, DVD+/-RW, DVD±R(W) and other arbitrary ways) handles all common writable disc types, but not DVD-RAM. A drive that supports writing to all these disc types including DVD-RAM (but not necessarily including cartridges or 8cm diameter discs) is ref ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
DVD-RAM
DVD-RAM (DVD Random Access Memory) is a DVD-based disc specification presented in 1996 by the DVD Forum, which specifies rewritable DVD-RAM media and the appropriate DVD writers. DVD-RAM media have been used in computers as well as camcorders and personal video recorders since 1998. In May 2019, Panasonic, the only remaining manufacturer of DVD-RAM discs, announced that it would end production of DVD-RAM media by the end of that month, citing shrinking demand as the primary motivation. Panasonic made these discs under its own brand name and also under the Verbatim brand. The "RAM" in its name is related to random-access memory that computers use as main memory, not in the technology but in sense that it can be used as a random-access memory unit rather than a sequential-access memory unit such as a magnetic tape drive. Format DVD-RAM works by means of phase change technology which was chosen instead of magneto-optical technology (an already existing rewritable solutio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Absolute Time In Pregroove
Absolute Time in Pregroove (ATIP) is a method of storing information on an optical medium, used on CD-R and CD-RW. ATIP information is only readable on CD-R and CD-RW drives, as read-only drives do not need the information stored on it. The information indicates if the disk is writable and information needed to correctly write to the disk. Usage ATIP is used as a method of putting data on an optical medium, specifically: * Manufacturer * Writable/Rewritable * Dye type * Spiral length in blocks * Rated speed * Audio These features are rather important to the function as it lets the drive know if it is writable. If the disc is re-writable, and the ATIP is damaged, it will not be able to write more than once. Also, it lets the drive know what the maximum write speed available for the disc is, and how much space (in blocks) the disc holds. Function Every writable disc has at least four layers: * Disc substrate – the bulk of the disc is 1.2 mm thick, and is usually injection m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
