# Inverse halftoning using wavelets

@article{Xiong1996InverseHU, title={Inverse halftoning using wavelets}, author={Zixiang Xiong and Michael T. Orchard and Kannan Ramchandran}, journal={Proceedings of 3rd IEEE International Conference on Image Processing}, year={1996}, volume={1}, pages={569-572 vol.1} }

This paper introduces a new approach to inverse halftoning using nonorthogonal wavelets. The distinct features of this wavelet-based approach are: a) edge information in the highpass wavelet images of a halftone is extracted and used to assist inverse halftoning, b) cross-scale correlations in the multiscale wavelet decomposition are used for removing background halftoning noise while preserving important edges in the wavelet lowpass image, c) experiments show that our simple wavelet-based… Expand

#### 17 Citations

Inverse halftoning using wavelets

- Mathematics, Medicine
- IEEE Trans. Image Process.
- 1999

This work introduces a new approach to inverse halftoning using nonorthogonal wavelets and shows that this simple wavelet-based approach outperforms the best results obtained from inverse Halftoning methods published in the literature, which are iterative in nature. Expand

A robust technique for image descreening based on the wavelet transform

- Computer Science, Mathematics
- IEEE Trans. Signal Process.
- 1998

A novel wavelet-based approach to recover continuous-tone (contone) images from halftone images is presented that lends itself to practical applications since it is independent of parameter estimation and, hence, universal to all types of halftoned images, including those obtained by scanning printed halftones. Expand

A Robust Nonlinear Filtering Approach to Inverse Halftoning

- Computer Science, Mathematics
- J. Vis. Commun. Image Represent.
- 2001

Distinct features of the proposed approach include efficiently smoothing halftone patterns in large homogeneous areas, additional edge enhancement capability to recover the edge quality, and an excellent PSNR performance with only local integer operations and a small memory buffer. Expand

Set theoretic inverse halftoning

- Mathematics, Computer Science
- Proceedings of International Conference on Image Processing
- 1997

A general method to recover a continuous-tone image from a halftone image in the situation where the halftoning algorithm is known and is applicable to all digital halftoned techniques. Expand

Image halftoning and inverse halftoning for optimized dot diffusion

- Computer Science
- Proceedings 1998 International Conference on Image Processing. ICIP98 (Cat. No.98CB36269)
- 1998

The dot diffusion algorithm and the optimization of the class matrix are reviewed and a method for inverse halftoning of dot diffused images is proposed that uses wavelet decomposition to eliminate the halftoned noise and does not make use of the knowledge of theclass matrix. Expand

Look-up table and Gaussian filter-based inverse halftoning method excellent in gray-scale reproducibility of details and flat regions

- Computer Science
- 2009

A new inverse halftoning method based on a combination of this LUT method and a Gaussian filter is discussed and the output gray-scale image is reproduced by blending the output of the LUT-based inverse Halftoning and that of the Gaussian filtering appropriately in accordance with local statistics of the image. Expand

An Inverse Halftoning Algorithms Based on Neural Networks and Atomic Functions

- IEEE Latin America Transactions
- 2017

Halftoning and inverse halftoning algorithms are very important image processing tools, widely used in the development of digital printers, scanners, steganography and image authentication systems.… Expand

Look up table (LUT) inverse halftoning

- Computer Science, Mathematics
- 2000 IEEE International Symposium on Circuits and Systems. Emerging Technologies for the 21st Century. Proceedings (IEEE Cat No.00CH36353)
- 2000

A novel method for inverse halftoning of images using a Look Up Table (LUT) based method that is extremely fast (no filtering is required) and also the image quality achieved is comparable to the best methods known for inverse Halftoning. Expand

Optimized halftoning using dot diffusion and methods for inverse halftoning

- Mathematics, Medicine
- IEEE Trans. Image Process.
- 2000

It is shown how the dot diffusion method can be improved by optimization of the so-called class matrix, by taking the human visual characteristics into account and showing that such optimization consistently results in images comparable to error diffusion, without sacrificing the pixel-level parallelism. Expand

Hybrid inverse halftoning using adaptive filtering

- Mathematics, Computer Science
- ISCAS'99. Proceedings of the 1999 IEEE International Symposium on Circuits and Systems VLSI (Cat. No.99CH36349)
- 1999

A novel fast inverse halftoning technique using a combination of spatial varying filtering and spatial invariant filtering is proposed, which is significantly simpler than most existing algorithms. Expand

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