About aliasing in signal processing, including computer graphics aliasing in computer programming aliasing ... Moire pattern of bricks small.jpg thumb 205px Spatial aliasing in the form of a Moir pattern . In signal processing and related disciplines, aliasing refers to an effect that causes different signals ... from samples is different from the original continuous signal. Description File Aliasing a.png thumb 200px Aliasing example of the A letter in Times New Roman. Left aliased image, right antialiased ... of spatial aliasing is the Moir pattern one can observe in a poorly pixelized image of a brick wall. Techniques that avoid such poor pixelizations are called anti aliasing . Aliasing can be caused ... aliasing anchor prealiasing prealiasing and reconstruction aliasing anchor postaliasing postaliasing ... 4 ISBN 0 89791 275 6 ref Temporal aliasing is a major concern in the sampling of video and Sound ... frequency components above 16000 hertz Hz the Nyquist frequency will cause aliasing when the music is reproduced ... above the Nyquist frequency with an Anti aliasing anti aliasing filter prior to sampling. But any ... or cinematography, temporal aliasing results from the limited frame rate, and causes the wagon wheel effect , whereby a spoked wheel appears to rotate too slowly or even backwards. Aliasing has changed ... . Temporal aliasing frequencies in video and cinematography are determined by the frame rate of the camera ... exposure time or the use of a temporal aliasing reduction filter during filming. ref name tessive ... number of samples per second. Some of the most dramatic and subtle examples of aliasing occur ... transform, has no upper bound. Some amount of aliasing always occurs when such functions are sampled ... aliasing is used intentionally on signals with no low frequency content, called bandpass signals. Undersampling ... isbn 0 13 146511 2 ref exploit aliasing in this way for computational efficiency. See Sampling signal ... transform . Understanding what aliasing does to the individual sinusoids is useful in understanding ... more details
for the method to replace command names in a computer shell Alias command In computing , aliasing describes ... to all aliased names, which may not be expected by the programmer. As a result, aliasing makes it particularly difficult to understand, analyze and optimize programs. Alias analysis Aliasing analysers intend to make and compute useful information for understanding aliasing in programs. Examples Array ... aliasing effects. If an array is created on the call stack stack , with a variable laid out in memory ... outside of the array is possible. Note that the aforementioned aliasing behaviour is implementation ... IEC 9899 1999, section 6.2.6.1 . It is not erroneous for a compiler to omit aliasing effects for accesses that fall outside the bounds of an array. Aliased pointers see also Pointer aliasing Another variety of aliasing can occur in any language that can refer to one location in memory with more than ... thereof for aliasing must be carefully documented, particularly for functions that perform complex manipulations on memory areas passed to them. Specified aliasing Controlled aliasing behaviour may be desirable in some cases that is, aliasing behaviour that is specified, unlike that relevant to memory ... constructs, aliasing behaviour, such as in tt foreach tt loops. This allows certain data structures ... wanted to bypass aliasing effects, one could copy the contents of the index variable into another and change ... ? Then, if the answer is no, code x 5 code can be propagated safely. Another optimization impacted by aliasing ..., known as strict aliasing , sometime allows for impressive increases in performance, ref cite ... Mike Acton date 2006 06 01 title Understanding Strict Aliasing ref but has been known to break some ... title ANSI strict aliasing and Python ref and required changes to the basic object structs in Python 3 to enable this optimisation. The Linux kernel does this because strict aliasing causes problems with optimization ... date 2003 02 26 title Re Invalid compilation without fno strict aliasing ref In such cases, when ... more details
Unreferenced date March 2007 see also Aliasing computing In computer programming , aliasing refers to the situation where the same memory location can be accessed using different names . For instance, if a function takes two pointers code A code and code B code which have the same value, then the name code A 0 code aliases the name code B 0 code . In this case we say the Pointer computer programming pointers code A code and code B code alias each other. Note that the concept of pointer aliasing is not very well defined two pointers code A code and code B code may or may not alias each other, depending on what operations are performed in the function using code A code and code B code . For instance, in code memcpy A 8, A, 8 code , the destination and source pointers do not alias, but in code memmove A 8, A, 9 code they do. Aliasing and re ordering Aliasing introduces strong constraints on program execution order. If two write accesses which alias occur in sequence in a program text, they must occur in sequence in the final machine code. Re ordering the accesses will produce an incorrect program result in the general case . The same is true for a write access and a read access. However, if two read accesses which alias occur in sequence in a program text, they need not occur in the same sequence in the machine code aliasing read accesses are safe to re order. This is because the underlying data is not changed by the read operation, so the same value is always read. It is vitally important that a compiler can detect which accesses may alias each other, so that re ordering optimizations ... types strict aliasing rules . This allows more optimizations to be done than in C. In C99 , the code ... language. Note that aliasing may still occur within a FORTRAN function. For instance, if code A code ... alias each other, but all pointers are read only. Thus, no alias analysis needs to be done. Aliasing ... section . Secondly, even with synchronization, if two aliasing accesses occur in different ... more details
IP aliasing is associating more than one IP address to a network card network interface . With this, one node on a computer network network can have multiple connections to a network, each serving a different purpose. In the Linux kernel, it was first implemented by Juan Jos Ciarlante in 1995. ref cite mailing list url http www.uwsg.iu.edu hypermail linux net 9512.0 0003.html title ip alias .... mailinglist Linux Net date 1995 11 30 last Ciarlante first Juan Jose ref It has also been possible in Microsoft Windows NT since at least Windows NT 3.51 , ref cite web title Adding More than Five IP Addresses to NIC in Windows NT MSKB 149426 work Microsoft Knowledge Base date October 31, 2006 url http support.microsoft.com kb 149426 accessdate 2010 07 26 ref released in 1995. References references DEFAULTSORT Ip Aliasing Category Internet compu network stub ... more details
An anti aliasing filter is a filter used before a signal sampler, to restrict the bandwidth of a signal ... is zero, a real anti aliasing filter can generally not completely satisfy the theorem. A realizable anti aliasing filter will typically permit some aliasing to occur the amount of aliasing that does ... aliasing filters are commonly used at the input of digital signal processing systems, for example ... of such systems, for example in music players. In the later case, the filter is to prevent aliasing ... would be required to guarantee zero aliasing. The theoretical impossibility of realizing perfect filters ... choices such as oversampling to make it easier to realize good enough anti aliasing filters. Optical anti aliasing filter Image anti aliasing filter.jpg thumb 250px Anti aliasing and IR reject filter ... camera s, the anti aliasing filter is also known as an optical lowpass filter or blur filter ...&dq anti aliasing lithium niobate&sig YUsQZMtxjtq70oOYWmU1K2yfoNY PPA30,M1 isbn 0240515900 ref The choice of spot separation for such a filter involves a tradeoff among sharpness, aliasing, and fill ..., if near 100 effective with microlenses, can provide a significant anti aliasing effect, ref cite book chapter Tradeoffs between aliasing and MTF title Proceedings of the Electro Optical Systems Design ... array CFA, e.g. Bayer filter cameras, an additional filter is generally needed to reduce aliasing ... anti aliasing filters&sig IWnjfbrjX oMXNkeW2ZBxH RBmg isbn 0824707702 ref ref cite book title Scientific ... page 61 url http books.google.com books?id AEFPNfghI3QC&pg PA61&dq aliasing fill factor&lr ... isbn 9783833414893 page 34 url http books.google.com books?id ZTJJ8QzNv1wC&pg PA34&dq aliasing fill ... cut off aliasing near the original low Nyquist frequency , while a much simpler analog filter can stop ... on the anti aliasing filter, or to further reduce the aliasing. Since the initial anti aliasing ... are not as stringent, and also allows the anti aliasing filter to have a smoother frequency ... more details
aliasing is the technique of minimizing the distortion artifacts known as aliasing when representing a high resolution image at a lower resolution. Anti aliasing is used in digital photography , computer graphics , digital audio , and many other applications. Anti aliasing means removing signal components ... noise near the top of figure 1 a Figure1 below . In signal acquisition and audio, anti aliasing is often done using an analog anti aliasing filter to remove the out of band component of the input signal prior to sampling with an analog to digital converter . In digital photography , optical anti aliasing .... The anti aliasing filter essentially blurs the image slightly in order to reduce resolution to below ... at the sensor level . See the articles on signal processing and aliasing for more information about the theoretical justifications for anti aliasing. Examples align right style margin left 5px anchor ... b center Image antialiased lanczos.png There are different algorithms for anti aliasing, creating ... framed Figure 2 In computer graphics, anti aliasing improves the appearance of polygon edges, so ... card and uses more video memory. The level of anti aliasing determines how smooth polygon ... when anti aliasing is not used. Notice that near the top of the image, where the checkerboard ... image. Figure 1 c shows another anti aliasing algorithm , based on the sinc filter , which is considered ... Leler, William J. title Human Vision, Anti aliasing, and the Cheap 4000 Line Display journal ACM .... In Figure 1 c, anti aliasing has interpolated the brightness of the pixels at the boundaries ... Figure 1 c appear much smoother than Figure 1 a at original magnification. In Figure 3, anti aliasing ... effect of the sharp, step like boundaries that appear in the aliased graphic at the left. Anti aliasing ... like ClearType . Subpixel rendering requires special color balanced anti aliasing filters to turn what ... based anti aliasing filter as is done in the OLPC XO 1 laptop s display controller. Pixel geometry ... more details
Temporal anti aliasing seeks to reduce or remove the effects of temporal aliasing . Temporal aliasing is caused by the Sampling signal processing sampling rate i.e. number of frames per second of a scene being too low compared to the transformation speed of objects inside of the scene this causes objects to appear to jump or appear at a location instead of giving the impression of smoothly moving towards them. To avoid aliasing artifacts altogether, the sampling rate of a scene must be at least twice as high as the fastest moving object. ref name grant Grant, C. 1985 . http doi.acm.org 10.1145 325165.325184 Integrated analytic spatial and temporal anti aliasing for polyhedra in 4 space . Computer Graphics publication SIGGRAPH Computer Graphics , 19 3 79 84 ref The shutter behavior of the sampling system typically a camera strongly influences aliasing, as the overall shape of the exposure over time determines the band limiting of the system before sampling, an important factor in aliasing. A temporal anti aliasing filter can be applied to a camera to achieve better band limiting. ref name tessive Tessive, LLC 2010 . http www.tessive.com home time filter faq 1 time filter technical explanation Time Filter Technical Explanation ref A common example of temporal aliasing in film is the appearance ... aliasing in computer graphics, the anti aliasing system requires a key piece of information which ... 10.1145 964967.801168 Temporal anti aliasing in computer generated animation . Computer Graphics ... concern, linear interpolation may be a better choice. Temporal anti aliasing can be applied ... some or all calculations for the above algorithm to be performed in object space. In spatial anti aliasing ... a valid approach to use in temporal anti aliasing the animation system can generate multiple instead ... system is used. ru Temporal anti aliasing See also Motion blur Anti aliasing Exposure photography Temporal posterization References Reflist DEFAULTSORT Temporal Anti Aliasing Category Computer graphics ... more details
Multisample anti aliasing MSAA is a type of anti aliasing , a technique used in computer graphics to improve image quality. Definition The term generally refers to a special case of supersampling . Initial implementations of full scene anti aliasing FSAA worked conceptually by simply rendering a scene at a higher resolution, and then downsampling to a lower resolution output. Most modern Graphics processing unit GPUs are capable of this form of antialiasing, but it greatly taxes resources such as texture bandwidth and fillrate . If a game is highly Transform, clipping, and lighting TCL bound or Central processing unit CPU bound, supersampling can be used without much performance hit. According to the OpenGL GL ARB multisample specification, ref http www.opengl.org registry specs ARB multisample.txt ARB multisample , Additions to Chapter 3 of the 1.2.1 specification ref multisampling refers to a specific optimization of supersampling. The specification dictates that the renderer evaluate ... anti aliasing, if any of the multi sample locations in a pixel are covered by the triangle ... once per pixel. The edges of polygons the most obvious source of aliasing in 3D graphics are antialiased .... The resulting image may contain aliasing along the edges of transparent objects or edges ... aliasing. ref http alt.3dcenter.org artikel multisampling anti aliasing index7 e.php Multisampling Anti Aliasing A Closeup View ref Translucent objects that are modelled using alpha test textures will also ... Anti Aliasing modes ref Aliasing Because multi sampling calculates textures only once per pixel, aliasing and other artifacts will still be visible inside rendered polygons where fragment shader ... cause aliasing and other artifacts. Sample patterns Regular grid A regular grid sample pattern, where ... number of samples. Quality Compared to supersampling, multisample anti aliasing can provide ... artikel multisampling anti aliasing index8 e.php Multisampling Anti Aliasing A Closeup View ref ... more details
Stroboscopic may refer to Stroboscopic effect , visual temporal aliasing Stroboscope , any of various stroboscopic devices Strobe light , high intensity and short duration stroboscopic device disambig ... more details
Alpha to coverage is a Multisample anti aliasing multisampling computer graphics technique useful for situations where dense foliage or grass must be rendered in a video game . This technique uses the Alpha compositing alpha channel of Texture mapping textures as a Mask computing Image masks coverage mask for anti aliasing . Alpha to coverage multisampling is based on regular multisampling, except that the Alpha compositing alpha coverage mask is Bitwise AND AND ANDed with the multisample mask. Alpha to coverage converts the Alpha compositing alpha component output from the pixel shader to a coverage mask. When the Multisample anti aliasing multisampling is applied each output fragment gets a transparency of 0 or 1 depending on alpha coverage and the Multisample anti aliasing multisampling result. References reflist 2 External links http http.developer.nvidia.com GPUGems3 gpugems3 ch04.html GPU Gems 3 Chapter 4. Next Generation SpeedTree Rendering http www.pcgameshardware.com aid,685997 Street Fighter IV PC explained in detail News Street Fighter IV PC explained in detail See also Anti aliasing Multisample anti aliasing compu graphics stub Category Image processing Category Computer graphic artifacts de Alpha to Coverage ... more details
Unreferenced stub auto yes date December 2009 This article is related to signal processing . For other meanings of the word Decimation , please see Decimation disambiguation . In digital signal processing , decimation is a technique for reducing the number of Sample signal samples in a Discrete signal discrete time signal . The element which implements this technique is referred to as a decimator . Decimation is a two step process Anti aliasing filter Low pass anti aliasing filter Downsampling An example of decimation the frequency of a recorded sound can be raised an octave in other words, doubled in frequency by eliminating every other sample without changing the sampling rate . This will result in aliasing if the sound contains overtones whose doubled frequency will exceed half the sampling rate. Decimation aliasing can be avoided by eliminating those overtones with a lowpass filter before downsampling. The same principle applies to eliminating samples at other intervals. DEFAULTSORT Decimation Signal Processing Category Digital signal processing Tech stub pl Decymacja cyfrowe przetwarzanie sygna w ru ... more details
MSAA may stand for Magical Shopping Arcade Abenobashi Microsoft Active Accessibility , a computer software development component Multiple Sclerosis Association of America Multisample anti aliasing , a 3D rendering technique disambig ru MSAA ... more details
CSAA may refer to Organisations California State Automobile Association Canadian Sociology and Anthropology Association Central Station Alarm Association Chinese Studies Association of Australia Technology Coverage Sampling Anti Aliasing , a technology first used in GeForce 8 Series disambig ... more details
Unreferenced date December 2009 An analog sampled filter an electronic filter that is a Hybrid integrated circuit hybrid between an analog filter analog and a digital filter . The input signal is analog signal analog , and usually stored in capacitor s. The time domain is Discrete time discrete , however. Distinct analog samples are shifted through an array of holding capacitors as in a bucket brigade . Analog adders and amplifiers do the arithmetic in the signal domain, just as in an analog computer . Note that these filters are subject to aliasing phenomena just like a digital filter, and anti aliasing filters will usually be required. See Filter design Companies such as Linear Technology and Maxim Integrated Products Maxim produce integrated circuit s that implement this functionality. Filters up to the 8th order may be implemented using a single chip. Some are fully configurable some are pre configured, usually as low pass filter s. Due to the high filter order that can be achieved in an easy and stable manner, single chip analog sampled filters are often used for implementing anti aliasing filters for digital filters. The analog sampled filter will in its turn need yet another anti aliasing filter, but this can often be implemented as a simple 1st order low pass analog filter consisting of one series resistor and one capacitor to ground electricity ground . DEFAULTSORT Analog Sampled Filter Category Linear filters Category Electronic circuits ... more details
CFAA may refer to Computer Fraud and Abuse Act Custom Filter Anti Aliasing disamb Short pages monitor This long comment was added to the page to prevent it being listed on Special Shortpages. It and the accompanying monitoring template were generated via Template Longcomment. Please do not remove the monitor template without removing the comment as well. ... more details
Wavelet noise is an alternative to Perlin noise which reduces the problems of aliasing and detail loss that are encountered when Perlin noise is Harmonic sum summed into a fractal . External links http graphics.pixar.com library WaveletNoise paper.pdf Wavelet Noise Paper at pixar.com. Category Computer graphics compu graphics stub ... more details
device. Solutions see Anti aliasing The effect of jaggies can be reduced somewhat by a graphics technique known as anti aliasing . Anti aliasing smooths out jagged lines by surrounding the jaggies ... of anti aliasing is that it reduces contrast rather than sharp black white transitions, there are shades ... thereof. In realtime computer graphics, especially gaming, Anti aliasing Full scene anti aliasing full screen anti aliasing FSAA is used to remove jaggies created by the edges of polygons and other ... Anti aliasing Temporal posterization Category Computer graphic artifacts Category Image processing ... more details
WS Topics is a web services specification that works as part of the WS Notification specification family, providing a method to define and address topics event notifications to which web service consumers can subscribe, as well as organising them into complex structures allowing hierarchy hierarchies topic trees and synonyms topic aliasing . In topic hierarchies topic trees , subscribing to a node also implies a subscription to all child nodes. Addressing Topics Topics can be addressed in three main ways each of which is a subset of the next SimpleTopic A QName that describes a topic this method can only address the root topics . ConcreteTopicPath A list of QName s that describes a path to a topic. FullTopicPath An expression in a subset of XPath that addresses topics using wildcards. Topic Aliasing Topic aliasing provides a formal way to declare that a topic is identical to another topic or group of topics found elsewhere in the topic space. Ad Hoc Topics The ad hoc topic space allows the dynamic definition of topic trees without the overhead of defining a new topic space. See also http docs.oasis open.org wsn wsn ws topics 1.3 spec os.pdf WS Topics 1.3 Specification Category Web service specifications Topics ... more details
Unreferenced date March 2007 Pitch cueing is the process a DJ does to seamlessly beat lock two different tracks. It is similar to the process of changing sample rate in the digital domain or time rotation speed in the analog domain. A direct implementation of rotation speed modulation in the digital domain is possible using simple array resampling and anti aliasing. A different implementation may yield a more intuitive interface. Category DJing music stub DJing ... more details
mathematics holomorph of the infinite cyclic group . Aliasing File Aliasing folding.svg thumb ... 0, f sub s sub 2 . br Here a horizontal line demonstrating the many to one phenomenon of aliasing ... f s, , math all of which thus lie in the same orbit they are aliases of one another . details Aliasing A concrete example of infinite dihedral symmetry is in aliasing of real valued signals this is realized ... is called aliasing Folding folding , as the graph of the detected signal folds back on itself, as depicted in the diagram at right. Formally, the quotient under aliasing is the orbifold ... more details
Wiktionary alias aliasing An alias is a pseudonym . In culture Alias TV series Alias TV series , an American television series Alias video game Alias video game , a video game based on the TV series Alias , a song from the album A Sense of Purpose by Swedish band In Flames Alias comics Alias comics , an American comic book Alias band , a rock band Alias album Alias album , an album by the band Alias Alias artist , Brendon Whitney, a hip hop artist Alias, the heroine of the novel Azure Bonds Samsung Alias or Samsung SCH U740 , a cell phone Alias Records , a record label Alias Enterprises , a United States publishing company Alias, the name used by singer songwriter Ryan Tedder when working as a producer Alias board game , a Finnish board game Alias film , a Belgian film by Jan Verheyen Alias the Jester , a figure in an English TV cartoon series In computing Aliasing , different continuous signals becoming indistinguishable when sampled Aliasing computing , multiple names for the same data location E mail alias , a virtual email address Alias command , a shell command Alias Mac OS , an icon linking to another file Alias Systems Corporation formerly Alias Wavefront PowerAnimator , an Alias Systems Corporation program also known as Alias Disambiguation cs Alias da Alias flertydig de Alias et Alias es Alias desambiguaci n fr Alias it Alias nl Alias ja pt Alias ru Alias sk Alias fi Alias sv Alias zh ... more details
of rasterization is simple line drawing with no anti aliasing of any sort. This is the fastest method ... complicated approach is to use standard anti aliasing techniques from computer graphics. This can be thought ... date 2009 12 29 accessdate 2010 09 12 ref RISC OS has featured font anti aliasing since ... s and Apple s implementations it supports hinting and anti aliasing, and optionally performs ... accessdate 2009 11 30 ref It provides anti aliasing, subpixel precision, automatic hinting, bitmap ... more details
A stale pointer bug , otherwise known as an aliasing bug , is a class of subtle programming errors that can arise in code that does dynamic memory allocation, especially via the malloc function or equivalent. If several Pointer computer programming pointer s address are aliases for a given hunk of storage, it may happen that the storage is freed or reallocated and thus moved through one alias and then referenced through another, which may lead to subtle and possibly intermittent lossage depending on the state and the allocation history of the malloc arena. This bug can be avoided by never creating aliases for allocated memory, by controlling the dynamic scope programming scope of references to the storage so that none can remain when it is freed, or by use of a garbage collection computer science garbage collector , in the form of an intelligent memory allocation library or as provided by high level programming language higher level languages , such as Lisp programming language Lisp . The term aliasing bug is nowadays associated with C programming language C programming, but it was already in use in a very similar sense in the ALGOL 60 and Fortran programming language communities in the 1960s. See also Dangling pointer FOLDOC Category Software bugs Category Software anomalies ar ... more details
4 would result in a sampling rate of 800 Hz. This gives the anti aliasing filter a transition band of 600 ... was virtually 200 Hz. An anti aliasing filter with a transition band of 600 Hz is much more realizable ... over then the transition band would increase to 1400 Hz, which means the anti aliasing filter could ... more details
unreferenced date September 2009 Image N64rcp.png thumb Casing of the Reality Co Processor chip RCP Reality Coprocessor Co Processor is one of two main chips for the Nintendo 64 the other being the NEC VR4300 . It was developed by Silicon Graphics for Nintendo, and little is known about it or the way it works. The RCP features a vector processor . It handles the audio and video of the Nintendo 64 and can perform very well in operations such as real time edge anti aliasing , high frame rate on complex images, automatic load management, advanced texture mapping , real time depth buffering , etc. During the development of GoldenEye 007 1997 video game GoldenEye 007 , a weapon RCP 90 was included as an in joke amongst the developers. Nintendo hardware N64 DEFAULTSORT Rcp Chip Category Nintendo hardware videogame hardware stub ... more details
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