Vishal Monga, Niranjan
Damera-Venkata, Hamood Rehman and Brian L. Evans
The University of Texas at Austin, Austin, TX 78712 USA
Version 1.2 works under both Matlab 6.5 and Matlab 7.0.
Version 1.1 and higher contains methods for both grayscale and color halftoning. Figures of merit are evaluated for the generated halftones.
Grayscale halftoning methods in the toolbox include
1. Classical and user-defined screens
2. Classical error diffusion methods
3. Edge enhancement error diffusion
4. Green noise error diffusion
5. Block error diffusion
Figures of merit measures for grayscale halftones
include
1. Peak signal-to-noise ratio (PSNR)
2. Weighted signal-to-noise ratio (WSNR)
3. Linear distortion measure (LDM)
4. Universal quality index (UQI)
Color halftoning methods in the toolbox include
1. Classical and user-defined (multilevel) screens (separable)
2. Classical separable error diffusion methods (separable)
3. Edge enhancement error diffusion (separable)
4. Green noise error diffusion (separable)
5. Block error diffusion (separable)
6. Minimum brightness variation quadruple error diffusion (non-separable design for separable implementation)
7. Vector error diffusion (non-separable)
Figures of merit measures for color
include
1. Peak signal-to-noise ratio (PSNR)
2. Weighted signal-to-noise ratio (WSNR)
3. Linear distortion measure (LDM)
4. Universal quality index (UQI)
5. Noise gain in dB over Floyd-Steinberg error diffusion
(specific to Vector Error Diffusion)
An introduction to halftoning methods, instructions on running the toolbox and the needed resources are available in the file "README.rtf".
References to appropriate texts and published conference and journal articles are made in the MATLAB files wherever required, and are available in the HELP entry for those files.
The toolbox depends on two Matlab toolboxes: Signal Processing Toolbox and Image Processing Toolbox.
Versions 1.0 and 1.1 of the toolbox were generated by Dr. Vishal Monga and Dr. Niranjan Damera-Venkata at UT Austin under the direction of Prof. Brian L. Evans. Mr. Hamood Rehman created version 1.2.
Dr. Vishal Monga and Prof. Brian L. Evans are currently with the department of Electrical and Computer Engineering at the University of Texas at Austin, TX - 78712. Dr. Niranjan Damera-Venkata is now with the Halftoning and Image Processing group at HP labs, Palo Alto, CA.
The previous releases of the halftoning toolbox are still available on this Web site:
For questions on the toolbox please write to vishal@ece.utexas.edu.