
	Where results make sense

Topic: Anisotropic filtering

Related Topics

Trilinear filtering

Bilinear filtering

ATI Technologies

Snes9X

SNES 2

VGA

Nintendo GameCube

RGB

Star Ocean

Customizing Nokia mobile phones

ZSNES

Modchip

SCART

In the News (Sun 27 May 12)

EXECUTIVE POWER

Iran

ANALYSIS

Pakistan

Family compact

	Anisotropy - Wikipedia, the free encyclopedia
		Anisotropic filtering (AF) is a method of enhancing the image quality of textures on surfaces that are far away and steeply angled with respect to the camera.
		This is not to be confused with an anisotropic filter, as used to filter particles, which is a filter with increasingly smaller interstitial spaces in the direction of filtration so that the proximal regions filter out larger particles and distal regions increasingly remove smaller particles, resulting in greater flow-through and more efficient filtration.
		Anisotropic etching techniques (such as Deep reactive ion etching) are used in microfabrication processes to create well defined microscopic features with a high aspect ratio.
	en.wikipedia.org /wiki/Anisotropic (549 words)

	Anisotropic filtering - Wikipedia, the free encyclopedia
		In 3D computer graphics, Anisotropic filtering (AF) is a method of enhancing the image quality of textures on surfaces that are far away and steeply angled with respect to the camera.
		Anisotropic filtering is computationally relatively expensive and has only recently become a standard feature of consumer-level graphics cards.
		In mip mapping, the mip level is anisotropic, so a 256x256 texture may be downsized to a 128x64 bitmap, which doubles its horizontal resolution.
	en.wikipedia.org /wiki/Anisotropic_filtering (504 words)

	nV News - NVIDIA GeForce3 Preview - Anisotropic Filtering
		Anisotropic filtering is a technique more suited to texturing angled surfaces, but requires additional processing in the form of texture memory reads.
		Anisotropic texture filtering calculates the shape of this ellipse and maps it onto the required texture.
		When used in conjunction with trilinear filtering, anisotropic filtering utilizes an additional average of 8, 16, or 32 texel samples within the ellipse to determine the color to be mapped to the target surface.
	www.nvnews.net /previews/geforce3/anisotropic.shtml (1503 words)

	X-bit labs - Articles - Anisotropic Filtering Investigation: NVIDIA GeForce3
		Anisotropic filtering considers the optic angle (the angle at which you look at an object surface), so the textures right in front of you get "smeared" along the object surface much more than in any other direction.
		To calculate a pixel color in bilinear filtering mode, for instance, the colors of four texels are used (or four "texture pixels" closest to the spot on the object surface, to which the pixel center is projected).
		In case of anisotropic filtering, ideally, the colors of all the texture samples falling into the pixel projection to the object should be taken into consideration.
	www.xbitlabs.com /articles/video/display/gf3-anis-filtering.html (1867 words)

	Richard Leader: Bargain Bin Review: Anisotropic Filtering
		Trilinear filtering specifies three regions allowing the central one set at mid-distance to blend the two other ranges of texture quality together, though lines are still visible) separating the three filtering sections) to astute observers.
		Anisotropic filtering allows for the gradual decrease in mip-map size over distance without any resulting visual lines delimiting the various zones.
		This results in a strange visual effect when using bilinear or trilinear filtering (the modes used by the majority of gamers) as the fence might sometimes be rendered using two different mip-maps with a seam between the two.
	www.richleader.com /bargainbinreview_anisotropic-filtering.htm (1074 words)

	Anisotropic Filtering (Site not responding. Last check: 2007-11-01)
		Anisotropic means "non-uniform shape" and it is because this filtering technique works on non-uniform, or uneven, shaped areas that it is more powerful, and takes much more processing power, than point sampling, bi-linear or tri-linear filtering.
		Anisotropic texture filtering calculates the shape of this ellipse, maps it onto the required texture and then takes an average of the colours from up to 32 texels within the ellipse to decide what colour should be plotted onto the target surface.
		Because anisotropic texture filtering requires so many calculations to be done to plot a single pixel, it has, until quite recently, been available only on the most expensive 3D hardware.
	www.meko.co.uk /anisofilter.shtml (357 words)

	Anisotropic filtering - DmWiki
		While mipmapping effectively reduces texture aliasing by deliberately blurring the texture, sometimes it blurs it too much; anisotropic filtering is a more accurate filtering method that allows the texture to appear sharp and crisp while still being free of aliasing.
		It's called anisotropic because the degree of filtering in one direction (the direction in which the polygon is tilted) is greater than the degree of filtering in the direction perpendicular to that.
		With anisotropic filtering, the only cost is taking the extra samples in the texture and averaging them together.
	www.devmaster.net /wiki/Anisotropic_filtering (456 words)

	August 2002 3Digest: Anisotropic filtering research
		So, bilinear filtering is used for removing sharp edges between texture pixels (for us to see the walls and floor textured not by squares, but by some smooth real-life materials), and trilinear filtering additionally dithers the scene once more interpolating edges of two bilinear-filtered MIP levels.
		Depending on filtering quality settings and surface viewing angle relative to screen plane, the standard bi- (or tri-) linear filtering is performed 1-4 times for points located on a straight line, drawn along dividing pixel, projected from the screen to texture surface along its long side (represented by an arrow on the figure).
		filtering quality will be high for values of projecting vector that are close to orts (an arrow on the figure), but as it turns, the effect will be still smaller down to the full loss of sense in using such method.
	www.digit-life.com /articles2/digest3d/1002/itogi-video-ani.html (1766 words)

	6.7 Anisotropic Texture Filtering
		This means that the amount of filtering done along the s and t axes of the texture is the same, and is the maximum of the filtering needed along each of the two axes individually.
		But since the minification filter is isotropic, the actual footprint is forced to a square that encloses the dark region.
		A mipmap level will be chosen in which this square footprint is properly filtered for the fragment; in other words, a mipmap level will be selected in which the size of this square is closest to the size of the fragment.
	www.opengl.org /resources/code/samples/sig99/advanced99/notes/node67.html (736 words)

	What is anisotropic filtering ? - a definition from Whatis.com
		- Anisotropic filtering (AF) is a feature of some video cards that sharpens the details of the fading-away part of a 3D object that recedes into the distance.
		In a 3D image, you may want a comparable effect to retain the sharpness of an object as it recedes; anisotropic filtering does this.
		Since anisotropic filtering requires intense processing as image frames are presented to the display, it may affect performance.
	searchsmb.techtarget.com /sDefinition/0,,sid44_gci870037,00.html (257 words)

	[No title]
		Implementations are free to use the specified minification and magnification filter to select a particular anisotropic texture filtering scheme.
		For example, a NEAREST filter with a maximum degree of anisotropy of two could be treated as a 2-tap filter that accounts for the direction of anisotropy.
		Implementations are also permitted to ignore the minification or magnification filter and implement the highest quality of anisotropic filtering possible.
	oss.sgi.com /projects/ogl-sample/registry/EXT/texture_filter_anisotropic.txt (772 words)

	Anisotropic filtering weirdness - Beyond3D Forum (Site not responding. Last check: 2007-11-01)
		Anisotropic filtering on the GF4 was originally hammered for it's poor performance, from which it has improved a tad since then in most recent drivers.
		On the other hand, if Z compression becomes lossy when anisotropic filtering is enabled, and it produces such significant differences, we shall see much more problems everywhere.
		Since anisotropic filtering increases the number of texels sampled, the reference value would have to decrease if you want to ensure that every pixel that has some of the fence in it is drawn.
	www.beyond3d.com /forum/showthread.php?t=592 (554 words)

	FS 3D Guide: Filtering and Lighting (Site not responding. Last check: 2007-11-01)
		Anisotropic filtering is the newest filtering method on the block.
		However, what separates anisotropic filtering from the others is that it is able to more correctly represent pictures that are angled to the viewer.
		Instead, anisotropic filtering is able to give more weight on sampling pixels on the horizontal edge (since it is a different proportion), and less relative sampling weight to the vertical edge, since the dimension there has not changed.
	www.firingsquad.com /guides/videolightfilter/page4a.asp (423 words)

	X-bit labs - Articles - NVIDIA GeForce3 Guide /part 2/
		Of course, anisotropic filtering requires a lot of computing resources and increases the memory bus workload significantly that's why you may notice a certain performance drop when this filtering is enabled.
		For example, in case of anisotropic filtering with 32 samples at lower resolutions the memory bus isn't overloaded because the CPU restricts the performance.
		However, fully-fledged trilinear filtering needs only 1 extra texturing unit to be involved in the process, which doesn't tell on the performance that greatly.
	www.xbitlabs.com /articles/video/display/geforce3_2.html (1698 words)

	Coding Horror: Anisotropic Filtering
		I've talked about Bilinear vs. Bicubic filtering before in the context of 2D images, but bilinear filtering is a key ingredient in 3D graphics, too.
		Proper anisotropic filtering is computationally expensive, even on dedicated 3D hardware.
		ATI was the first 3d hardware vendor to introduce some anisotropic filtering optimizations-- some would say shortcuts-- in their cards which allowed much higher performance.
	www.codinghorror.com /blog/archives/000484.html (775 words)

	Rage3D - ATI Radeon X1800 XT Technology Preview - Image Quality - Anisotropic Filtering
		ATI kicked off the trend with their angle-dependant filtering techniques on the 9700 Pro, which helped significantly with frame rates but didn't look as good in certain situations.
		More significantly, they have added a new feature, simply known as HQ AF, to their filtering engine that greatly improves overall texture filtering quality by vastly reducing the angle dependant filtering algorithms that are normally used.
		The first app shows us that the default filtering mode of the X1800 has a sample pattern which is about the same as the X850 before it, and that both of them use angle-dependent filtering optimizations.
	www.rage3d.com /reviews/video/atix1800xt/?p=11 (966 words)

	Sharky Extreme - '+$ArtG+' - '+$ArtC+' - '+$ArtN+'
		Fortunately, the next-generation of graphics boards should be introducing 32-tap and higher sampling levels of anisotropic filtering in the near future.
		Anisotropic is going to quickly become an important feature.
		And further down the road, we can expect hardware to support even higher levels of anisotropic filtering, such as 128-tap, yet another step down the technology path that leads to the merging of real world and rendered images.
	www.sharkyextreme.com /hardware/guides/texture_filtering/6.shtml (277 words)

	TR interviews ATI's David Nalasco - The Tech Report - Page 6
		When anisotropic filtering is enabled via the control panel, then only the first texture layer has trilinear filtering applied.
		In the case of anisotropic filtering, we wanted to give people a way to enable it in games that don't specifically or explicitly support it in a way that, again, improves image quality without having a huge impact on performance.
		Much like our anisotropic filtering algorithm, we don't do 16X anisotropic filtering, which requires 128 texture samples, if you're staring straight at a wall when it will look no different than using a single texture sample.
	www.techreport.com /etc/2004q2/nalasco/index.x?pg=6 (1522 words)

	RADEON 8500 - Driven To New Heights \| Tom's Hardware
		On the Radeon, anisotropic filtering uses blocks of already-blended samples [bilinear (4) or trilinear (8)].
		According to ATi, R8500's impressive performance when using anisotropic filtering is the result of a dynamic filter implemented in the driver.
		For example, if you are standing right in front of a wall in a first-person shooter, the driver will only use bilinear filtering (4 texels), since the difference in quality when using anisotropic filtering (64 texels) would be all but unnoticeable (a claim which remains to be proven).
	www.tomshardware.com /2001/11/23/radeon_8500_/page4.html (704 words)

	Anisotropic Texture Filtering (DirectX8 C/C++ Archive)
		Anisotropy is the distortion visible in the texels of a 3-D object whose surface is oriented at an angle with respect to the plane of the screen.
		When a pixel from an anisotropic primitive is mapped to texels, its shape is distorted.
		Set the value of the first parameter to the integer index number (0-7) of the texture for which you are selecting a texture filtering method.
	msdn.microsoft.com /archive/en-us/dx8_c/directx_cpp/graphics_using_20xf.asp?frame=true (290 words)

	AnandTech: NVIDIA GeForce 6800 Ultra: The Next Step Forward
		Trilinear filtering optimizations can be turned off (doing full trilinear all the time), and a new "High Quality" rendering mode turns off adaptive anisotropic filtering.
		We appreciated the fact that NVIDIA's previous implementation of anisotropic filtering employed a Euclidean distance calculation which is less sensitive to the orientation of a surface than a weighted Manhattan calculation.
		The advantage is that NVIDIA now has a lower impact when enabling anisotropic filtering, and we will also be doing a more apples to apples comparison when it comes to anisotropic filtering (ATI also makes use of a weighted Manhattan scheme for distance calculations).
	www.anandtech.com /showdoc.aspx?i=2023&p=8 (766 words)

	nHancer (Site not responding. Last check: 2007-11-01)
		For a trilinear filter, 8 texel samples have to be taken for each rendered pixel.
		The quality of the Anisotropic Filtering is indicated by the factor of the additional samples.
		With lower screen resolutions, the effect of Anisotropic Filtering is more pronounced, but it's effect is visible in every resolution.
	www.nhancer.com /help/enhancements.php (1392 words)

	The Naked Truth About Anisotropic Filtering
		Usable anisotropic filtering (AF) is one of the more recent effects to migrate from the digital cinematographer's workstation to the PC, joining bilinear and trilinear filtering, among others (for a complete description of AF, see the next section).
		Real-time 3D is the fl art of getting the most visual bang for the least processing horsepower/memory bandwidth buck, and as real-time 3D in games continues to approach CG effects in films, the incremental improvements have become increasingly subtle, though still important.
		Anisotropic filtering would seem to be the next frontier of texture filtering in 3D, but if applied to every pixel in a scene, it can induce a severe performance hit.
	www.extremetech.com /article2/0,3973,548248,00.asp (740 words)

	Asus V8420 Deluxe GF4 Ti4200 - Hot Hardware
		Anisotropic Filtering is another filtering method used to clean up image quality by filtering textures in order to prevent "fuzziness" on sloped surfaces.
		We should also mention that what NVIDIA calls 32-Tap Anisotropic filtering (4X in their drivers) is not what ATi calls 32-Tap Anisotropic filtering (8X in their drivers).
		Another thing to consider is that the Radeon 8500 we used for testing can't do trilinear filtering when Anisotropic filtering is enabled.
	www.hothardware.com /viewarticle.aspx?page=3&articleid=320 (499 words)

	[No title]
		Background Texture filtering is the process of sampling the texture function (represented by a texture image) at a pixel.
		Ideally the filtered color would be a weighted average of all the texels covered by the footprint, but the cost of computing the coverage and accessing each texel would make real-time rendering virtually impossible.
		Anisotropic texture filtering, through whatever mechanism it is implemented, is the process of sampling a texture function with a reconstruction filter that is narrow and long in texture space.
	www.nps.navy.mil /cs/sullivan/MV4470/resources/filter_anisotropic2.doc (1702 words)

	Castro-Pareja, Dandekar and Shekhar (2005) FPGA-based real-time anisotropic diffusion filtering of 3D ultrasound images (Site not responding. Last check: 2007-11-01)
		Three-dimensional ultrasonic imaging, especially the emerging real-time version of it, is particularly valuable in medical applications such as echocardiography, obstetrics and surgical navigation.
		Anisotropic diffusion filtering has been shown to be effective in enhancing the visual quality of 3D ultrasound images and as preprocessing prior to advanced image processing.
		We present an FPGA-based architecture that allows performing anisotropic diffusion filtering of 3D images at acquisition rates, thus enabling the use of this filtering technique in real-time applications, such as visualization, registration and volume rendering.
	www.getcited.org /pub/103411992 (158 words)

	AnandTech: Matrox's Parhelia - A Performance Paradox (Site not responding. Last check: 2007-11-01)
		When anisotropic filtering is enabled, both Matrox and NVIDIA are always applying the filtering technique.
		The Radeon 8500 however calculates when it believes that anisotropic filtering is necessary and only uses it then, otherwise it defaults to a lesser filtering technique.
		The benefit of this is that the performance hit incurred while enabling anisotropic filtering is next to nothing so you can increase the degree of texture anisotropy without taking too big of a performance hit.
	www.anandtech.com /showdoc.html?i=1645&p=12 (500 words)

Try your search on: Qwika (all wikis)