Video scaling lets the user stretch out the viewing area of the video clip up to full screen so the clip is viewable in a display larger than the small Media Player viewing screen. A video clip is usually captured at 160 x 120 or 320 x 200 resolution, so scaling the video increases that resolution to 640 x 480 and above.

Pixel Interpolation is the technique most video cards use during video scaling. Interpolation calculates the color information needed to allow for a smooth transition between pixels that have become separated by scaling up in size.

X and Y-scaling improves video quality by interpolating in horizontal and vertical directions.

Color Space Conversion is the method used to convert YUV signals, data used to better compress composite signals, to RGB signals, information recognizable by the monitor.

Dithering allows you to play a video clip in less than 16.7 million colors, the color depth that MPEG and AVI clips are originally recorded in. (i.e. - you can use the Window’s drivers with either 256 or 65K colors).

All PC video is compressed by a CODEC which stands for compression/decompression.

Decompression of the CODEC (Compression/Decompression) is done completely with software through the CPU. Hardware video acceleration only handles the tasks listed on the previous slide.

Examples of CODECs include:

• MS Video 1
• Cinepak Supported through Video for Windows disk
• Indeo 3.2
• MPEG-1 - Supported through Mediamatics, Compcore or Xing disk
• MPEG-2 - Video compression standard for DVD video

Video for Windows files commonly have an .AVI extensions
MPEG files commonly have an .MPG extensions
(.MP3 for MPEG sound files.)