A novel halftoning approach that has embedded in it a model for the electrophotographic process is presented. Models for the laser beam, exposure of the organic photoconductor, and the resulting absorptance on the paper are embedded into the direct binary search (DBS) halftoning algorithm. The algorithm is applicable to any arbitrary pixel modulation scheme and is also highly portable between different electrophotographic print engines. Computational issues are addressed to make the approach viable. Results show good exploitation of pixel modulation and improvement over DBS with no printer model throughout most of the tone scale.

A spread spectrum watermarking algorithm for hardcopy imaging applications using a human visual system model based halftoning technique called direct binary search (DBS) is presented. DBS is used to design a halftone that jointly optimizes a human visual system based error metric and correlation watermark detector output. The original image is required for the correlation watermark detector.

A wavelet decomposition based surface compression technique to represent the forward transformation for a color printer is presented. The method creates a multi-scale grid structure for a given maximum pointwise error threshold. The error performance, the memory requirement, and the computational cost of this technique are compared with those of minimax sequential linear interpolation (SLI) and minimum mean-squared (MMSE) SLI.

The usefulness of multichannel filtering for image texture segmentation has been demonstrated in the literature. Based on psychophysical studies, it has been largely believed that Gabor filters are optimal for segmentation. In this paper, the application of maximally decimated, non-separable, perfect reconstruction filter banks (subband systems) are investigated for texture segmentation. The subband decomposition used in this paper forms a maximally decimated filter bank and therefore computation time and complexity is much less than the full rate case of the Gabor filters. The directional selectivity achieved by the non-separable, multirate filter bank results in performance similar to that achievable with the Gabor filters, but with a drastically reduced computational load.