S3 Graphic's Chrome S27

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Chromotion 3.0 - ChromeView Non-Linear Scaling

Chromotion 3.0 - Continued
ChromeView Non-Linear Scaling

To handle the Chrome S27's video scaling capabilities, S3 utilizes a number of technologies depending on the specific task.  With regard to certain types of HDTV output, S3's ChromeView Non-Linear Scaling feature comes into play.  In essence, when it's necessary to output a standard 4:3 aspect ratio image to an HDTV screen, compensation must occur to fit the image to the HDTV's 16:9 aspect ratio.  One method is to leave the target image unchanged, fitting the image to the screen vertically and leaving the horizontal width unchanged.  This maintains the image's original aspect ratio, which results in vertical black bands on either side of the image.


Direct Scaling

Another method is Simple Linear Horizontal Scaling which stretches the image to fit the 16:9 aspect ratio of the HDTV monitor, but results in severe stretching of the image, which is not going to be acceptable in most situations.


Simple Linear Horizontal Scaling

The last option is Non-Linear Horizontal Scaling of the image.  With this technique, the center of the image is left unchanged while the sides of the image are stretched to fit the remainder of the screen.  In most cases, the viewer is focusing on the center of the screen, so the stretching effect applied on the sides is more tolerable that with Simple Linear Horizontal Scaling.


Non-Linear Horizontal Scaling

With Non-Linear Horizontal Scaling, in situations where a 4:3 aspect ration image needs to be scaled to an HDTV 16:9 image area, this method offers a balanced solution that minimizes distortion on the main subject, which makes this method the most viable option when needed. 

When ChromoVision is enabled, ChromeView offers four options, giving the user the option to decide which method best applies to their situation.  Normal mode leaves the image in its normal aspect ratio, resulting in black bands on the left and right of the image.  Zoom mode displays letterboxed 4:3 images while Full mode is uses linear scaling to stretch a 4:3 aspect ratio image to 16:9.  Non-Linear Mode uses ChromoView's Non-Linear Scaling methods to stretch the image while minimizing distortion.

Tags:  S3, Chrome, s2, Graphic, rom, 27, AP

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