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Inverse halftoning algorithm using edge-based lookup table approach.

Kuo-Liang Chung·Shih-Tung Wu
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Abstract

The inverse halftoning algorithm is used to reconstruct a gray image from an input halftone image. Based on the recently published lookup table (LUT) technique, this paper presents a novel edge-based LUT method for inverse halftoning which improves the quality of the reconstructed gray image. The proposed method first uses the LUT-based inverse halftoning method as a preprocessing step to transform the given halftone image to a base gray image, and then the edges are extracted and classified from the base gray image. According to these classified edges, a novel edge-based LUT is built up to reconstruct the gray image. Based on a set of 30 real training images with both low-and high-frequency contents, experimental results demonstrated that the proposed method achieves a better image quality when compared to the currently published two methods, by Chang et al. and Meşe and Vaidyanathan.

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AlgorithmsArtificial IntelligenceComputer GraphicsData CompressionDatabases, FactualImage EnhancementImage Interpretation, Computer-AssistedNumerical Analysis, Computer-AssistedPattern Recognition, AutomatedSignal Processing, Computer-AssistedEvaluation StudyJournal ArticleResearch Support, Non-U.S. Gov't

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Kuo-Liang Chung, Shih-Tung Wu. 2005. Inverse halftoning algorithm using edge-based lookup table approach.. https://doi.org/10.1109/tip.2005.854494

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