X-bit labs

S3 GammaChromeS18 Graphics Processor Preview (page 7)

Category: Video

by Anton Shilov , Anna Filatova

[ 03/14/2005 | 07:34 AM ]

Chromotion 2.0

The new S3G graphics processor also acquired a new version of the programmable Chromotion engine, which we have already discussed in detail in our article called The Return of S3: DeltaChrome Graphics Card Review. Chromotion 2.0 is fully compatible with DirectX-VA and can process any video formats: WMV, MPEG-2, MPEG-4/DivX, etc. The list of supported features for Chromotion 2.0 is pretty long:

• Film-Like Video with Per Pixel Adaptive Deinterlacing;
• High Quality Video Scaling with the Programmable Kernel Filter;
• ArtisticLicense Effect Generation with Advanced Real-time Image Processing Soft Focus, Embossed, Sharpen, and Neon Edges Artistic Effects;
• Video Deblocking Image;
• MPEG-2/4 Hardware acceleration;
• Hardware Accelerated IDCT and Motion Compensation;
• ChromoColor;
• PureFlow TV;
• ChromoVision full screen video on TV or HDTV;

The last three items are the most interesting ones, I should say, since these are brand new features, which didn’t exist in the old engine version. Let’s take a closer look at them now.

ChromoColor technology allows adjusting brightness, contrast, hue and saturation of the video playback with the help of special pixel shaders instead of using the Overlay Engine. This approach has certain advantages: the settings work for an unlimited number of video streams, while the traditional adjustment is usually limited by the number of overlay engines.

ChromoColor mode is enabled automatically when the S3G drivers detect the corresponding hardware in the system. The settings can be modified in the S3G Color Plus page:

The idea behind PureFlow Technology implies that the color data do not get transformed during video files playback or image display on the TV screen. PureFlow technology allows direct transmission of YUV data to the TV encoder. Without this technology the YUV data needs to be converted to RGB format inside the graphics processor before it is displayed onto a TV screen, even if the device connected to the TV-Out of the graphics card is working in the full-screen mode.

The conversion of YUV to RGB is a complex process involving floating-point calculations, which automatically results into certain errors during rounding operations and this inevitably tells on the quality of the final image. PureFlow technology allows skipping the conversion if the display device is working in the full-screen mode. This approach improves the image quality, because there are no errors resulting from inaccurate conversion procedures that affect the final image.

S3G PureFlow technology works with regular TV-sets as well as with HDTV devices, since YPbPr format is simply another variation of HDTV.

ChromoVision allows borderless video playback full screen on a TV or HDTV while windowed video plays on a fully functional desktop visible on another display device. ChromoVision can be enabled if two display devices are connected to the primary output port. The user can resize the window or move it on the PC monitor without any visible effects displaying on the TV screen or HDTV device. The Chromotion effects will however be displayed on both: PC monitor window as well as the full-screen video.