Data compression of scanned halftone images

Data compression of scanned halftone images

A new method for coding scanned halftone images is proposed. It is information-lossy, but still preserving the image quality, compression rates of 16-35 have been achieved for a typical test image scanned on a high resolution scanner. The bi-level halftone images are filtered, in phase with the halftone grid, and converted to a gray level representation. A new digital description of (halftone) ...

Reconstruction from Scanned Halftone Images

Suppression of moiré patterns in scanned halftone images

Moiré patterns often appear in the image obtained from scanning an image printed on a magazine or a newspaper. The patterns do not exist in the original printing but come from alias sampling of screened halftone pictures. A strategy to design a moiré suppression scanning procedure is proposed. Fourier analysis is presented for both the screening and the scanning processes, from which a formula ...

Lossy Compression of Scanned Map Images

An algorithm for lossy compression of scanned map images is proposed. The algorithm is based on color quantization, efficient statistical context tree modeling and arithmetic coding. The ratedistortion performance is evaluated on a set of scanned maps and compared to JPEG2000 lossy compression algorithm, and to ECW, which is a commercially available solution for compression of satellite and aer...

Hiding Data in Halftone Images

Most recent papers about visual cryptography for halftone images are dedicated to get a higher contrast decoded image. However, the hidden visual pattern often blends into the background image and leads to a confused image. In this paper, we propose an improved method for halftone image hiding. By using the proposed method, the background image can be eliminated and the hidden visual pattern ca...