Guotong Feng

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Effective document compression algorithms require scanned document images be first segmented into regions such as text, pictures and background. In this paper, we present a document compression algorithm that is based on the 3-layer (foreground/mask/background) MRC (mixture raster content) model. This compression algorithm first segments a scanned document(More)
Conventional halftoning methods such as error diffusion and ordered dithering are poorly suited to the compression of halftone images using the baseline fax compression schemes CCITT G3 and G4. This paper proposes an efficient and flexible solution for binary representation of mixed content documents using CCITT G3/G4 compression. The solution includes two(More)
Recent research demonstrates the advantage of designing electro-optical imaging systems by jointly optimizing the optical and digital subsystems. The optical systems designed using this joint approach intentionally introduce large and often space-varying optical aberrations that produce blurry optical images. Digital sharpening restores reduced contrast due(More)
It has been shown that electro-optical imaging systems designed by integrating optics and digital processing provide system-level advantages such as extended depth-of-field and lower optical component costs. In such imaging systems, the strength of the optical aberration or blur can dramatically change with the f-number, and hence different digital filters(More)
This paper reports on novel and traditional pixel and semantic operations using a recently standardized document representation called JPM. The JPM representation uses compressed pixel arrays for all visible elements on a page. Separate data containers called boxes provide the layout and additional semantic information. JPM and related image-based document(More)
Document imaging and transmission systems (typically MFPs) require both effective and efficient image rendering methods that support standard data formats for a variety of document types, and allow for real time implementation. Since most conventional raster formats (e. g. TIFF, PDF, JPEG) are designed for use with either black and white text, or(More)
Raster document coders are typically based on the use of a binary mask layer that efficiently encodes the text and graphic content. While these methods can yield much higher compression ratios than natural image compression methods , the binary representation tends to distort fine document details, such as thin lines, and text edges. In this paper, we(More)
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