A Two-Dimensional Quantizer for Coding of Digital Imagery

A spatial domain image coding method which is computationally straightforward and requires only one pass through the incoming data is presented. The technique is based on approximating a near-optimal three-level uniform quantizer over a spatially local region of the image. This method can maintain single pixel resolution and is therefore applicable to wide bandwidth data. Results of applying this procedure to a variety of images are given, along with comparisons to some other image coding techniques. A variablelength code word version providing increased compression is also developed.