Microsoft KB Archive/228383

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Quality Is Lost When You Convert a Graphic from RGB to YUV on a Computer by Using an S3 Savage4 driver

Article ID: 228383

Article Last Modified on 10/30/2006



APPLIES TO

  • Microsoft Windows 2000 Professional Edition



This article was previously published under Q228383

SYMPTOMS

When you view YUV-formatted graphics or videos on a computer with the hibernation mode turned on and with an S3 Savage4 driver in use, you find that the pixels appear larger, and the detail of the graphic is lost. This behavior occurs when an RGB graphic is converted to YUV format.

STATUS

This behavior is by design.

MORE INFORMATION

YUV Color System is a color-encoding scheme for natural pictures in which the luminance and chrominance are separate. The human eye is less sensitive to color variations than to intensity variations, so YUV allows the encoding of luminance (Y) information at full bandwidth and chrominance (UV) information at half bandwidth.

The primary colors in color video are red, green, and blue (RGB). RGB is often used to describe a type of video color-recording scheme and the type of equipment that uses it. It also describes a type of computer color display output signal comprising separately controllable red, green, and blue signals (as opposed to composite video, in which signals are combined before output). RGB monitors typically offer higher resolution than composite monitors.

More complex graphics may not be able to stand the conversion from RGB to YUV without losing quality. Data in a YUV format shares every two pixels in a Y component, and every four pixels in U and V components. This results in image details, like the text, being lost in the RGB-to-YUV conversion. Also, the program you use for the conversion may just delete pixels instead of merging them, causing the quality to be lower.

For additional information, click the article number below to view the article in the Microsoft Knowledge Base:

108803 MultiMedia Glossary


The third-party products that are discussed in this article are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.


Keywords: kbprb KB228383