|Image smoothing performs anti-aliasing (smoothing) of images when 'scaling up'. Eg. Scaling an 800x600 image to 1024x768 using simple pixel or line duplication would given uneven 'blocky' results as some pixels are doubled-up and some are not. Image smoothing ensures these effects are reduced by merging pixels and lines together.|
The standard value is 'High' for maximum reduction of blocky pixels. However, this can be detrimental for high Zoom levels where a crisp 'blocky' pixel is desired.
The (default) 'Auto' option has thus been added to reduce Image smoothing gradually from High to Medium and then Off as the Zoom level increases.