X-bit labs

Thursday, July 7, 2005

Web-Site Explains Image Quality Improving Techs. FSAA and AF in Details

Bit-tech.net has posted an article wish explains some standard modern graphics cards features. The Full Scene Anti-Aliasing (FSAA) as well as Anisotropic Filtering (AF) technologies implemented in all of the latest graphics cards are aimed to enhance image quality in 3D applications. The article includes some analysis and picture quality comparison made with and without FSAA and AF enabling.

“If you can’t increase resolution, you turn to anti-aliasing which, as the name might suggest, is a technique designed to reduce the appearance of jagged lines. Anti-aliasing blends the edges of shapes using color to make them less harsh, effectively fooling the eye into thinking the line is smoother than it is. Of course, this blending reduces the sharpness of the line and over-blending can make it blurry. Anti-aliasing techniques aim to keep blurring to a minimum whilst reducing the aliasing that can be apparent,” writes Bit-tech.net.

While FSAA is aimed at reducing the appearance of jagged lines, anisotropic filtering is designed to insure better quality of the whole scene and improve the clarity of the textures. 

“To understand this technique, we must understand how textures are applied to a 3D scene on your screen. Textures are the images, the details if you like, that sit on top of bare lines. A scene rendered without textures looks blocky and simple, whereas a scene with textures on immediately adds realism. As a 3D scene stretches into the distance, less detail is required as the objects become further away. Rendering textures that are far away at a lesser detail than those that are closer to the player means that graphics cards can give better performance. These lower-quality distance textures are called mipmaps. However, what can be evident are the points at which the different levels of texturing change. Often, changes between mipmap levels are all too evident on the screen. Textures are therefore filtered to make the transitions between different levels smoother. The higher the level of anisotropic filtering, the better image quality is achieved for mipmap transitions,” writes the author.

• Bit-tech.net: Aliasing and Filtering Explained.

The Cell Processor Gets Previewed. Cell Processor Architecture under Investigation

The Cell processor developed by IBM, Sony and Toshiba unveiled earlier this year is probably the first consumer-oriented chip that attracts a lot of interest, which Dev Hardware web-site has decided to address as in-depth as possible.

The Cell processor is a yet another multi-core approach which should provide strong performance and while half a year after Cell’s release it is no longer unusual to hear about multi-core architecture, the Cell chip utilizes a bit different approach than AMD’s and Intel’s dual-core products which are available for purchase at the moment.

Early reviews showed that current software applications cannot benefit from additional core on a die, and since Cell processor was only demonstrated on E3 exhibition and never made its way to the hands of hardware editors, the question of Cell performance in real life applications is still open.

“IBM is trying to accelerate Cell’s development by lifting limitations and revealing its structure; in this way, talented programmers can better understand the processor and program for it more easily than otherwise. This might make it attractive for some companies that want great performance that the Cell delivers without extreme costs. IBM might also get some free hardware and software development from these opportunistic companies and from some helpful individuals. Open hardware could bring flexibility and usefulness to Cell systems that it couldn’t have reached before,” speculates Dev Hardware.

• Dev Hardware: Cell Inside, the Future of Processor Architecture.