Quantization of accumulated diffused errors in error diffusion

Abstract

Quantization of the accumulated diffused error (ADE) is an effective means to reduce on-chip storage in a hardware implementation of error diffusion. A simple uniform quantizer can yield a factor of 2 savings with no apparent loss in image quality. Nonuniform quantizers with memory that depend on the quantizer index or various features13 can yield even greater savings -- up to a factor of 4, with essentially no loss in image quality. However, these quantizers depend on the trainability of the tone-dependent error diffusion (TDED) framework to achieve this level of quality. In addition, the design of the quantizers must be coupled to that of the TDED parameters in either a sequential or iterative fashion.