Bit-Swizzling and Filtering for Real-Time Grey Scale Display

The use of grey scale is a way of increasing the apparent bandwidth and potential image quality of a display system without a corresponding increase in its frequency response. The ongoing trend to higher screen resolution has been accompanied by a substantial increase in monitor cost; we seek to achieve high quality images for the lowest cost. The Gnot terminal was designed largely as an experiment in trading off spatial resolution in favor of grey scale. Preliminary results have been very good, and point out the need for grey scale rendering techniques that approach bitmap techniques in speed. This talk describes specific algorithms and techniques for turning bitmap images into grey scale images at lower resolution. While this approach may not result in the highest possible image quality at a certain level of grey scale, rendering in bitmaps is very simple and the conversion to grey scale can be very fast.