Fig. 5: Effect of automatic color equalization (ACE) on a manuscript image. | npj Heritage Science

Fig. 5: Effect of automatic color equalization (ACE) on a manuscript image.

From: Restoration of ancient Japanese manuscripts via the diffusion denoising restoration model and color space-based masking

Fig. 5

Example showing the impact of color normalization using Automatic Color Equalization (ACE)37. (Left) Original manuscript image cropped from high-resolution scans of the Tsurezuregusa manuscript (National Institute of Japanese Literature, CODH dataset) using LabelImg. (Right) The same image after ACE correction, where the color distribution has been normalized and the contrast between text and background has been enhanced. ACE effectively compensates for uneven illumination and discoloration, reduces the yellowish tint, and improves the separability between ink and paper regions.

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