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Improving the Visual Quality of Size-Invariant Visual Cryptography for Grayscale Images: An Analysis-by-Synthesis (AbS) Approach

Version 2 2024-06-03, 11:49
Version 1 2018-10-26, 15:31
journal contribution
posted on 2024-06-03, 11:49 authored by B Yan, Yong XiangYong Xiang, G Hua
In visual cryptography (VC) for grayscale image, size reduction leads to bad perceptual quality to the reconstructed secret image. To improve the quality, the current efforts are limited to the design of VC algorithm for binary image, and measuring the quality with metrics that are not directly related to how the human visual system (HVS) perceives halftone images. We propose an analysis-by-synthesis (AbS) framework to integrate the halftoning process and the VC encoding: the secret pixel/block is reconstructed from the shares in the encoder and the error between the reconstructed secret and the original secret images is fed back and compensated concurrently by the error diffusion process. In doing so, the error between the reconstructed secret and original secret is pushed to high frequency band, thus producing visually pleasing reconstructed secret image. This framework is simple and flexible in that it can be combined with many existing size-invariant VC algorithms, including probabilistic VC, random grid VC and vector/block VC. More importantly, it is proved that this AbS framework is as secure as the traditional VC algorithms. Experimental results demonstrate the effectiveness of the proposed AbS framework.

History

Journal

IEEE Transactions on Image Processing

Volume

28

Pagination

896-911

Location

United States

ISSN

1057-7149

eISSN

1941-0042

Language

English

Publication classification

C1 Refereed article in a scholarly journal

Copyright notice

2018, IEEE

Issue

2

Publisher

IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC