The Importance of Dithering Technique Revisited With Biomedical Images—A Survey

Abstract

Dithering is used regularly for printing monochrome images. Newspaper photographs are dithered for example. In the monochrome images, each pixel is stored as a single bit. The smallest unit of the digital image is a pixel, i.e., the picture element. The bits-per-pixel is the significant metric to the appearance level of the nature of the image. To obtain the diverse gray shades, different patterns of white and black dots are used. This paper deals with the underlying fundamental behind the dithering with medical test images. The techniques such as quantization, dithered, dithered and quantized, dithered and quantized with subtraction, and the adoption of filtering kernel are implemented. The performance of each one is evaluated with mean-square-error and peak signal-to-noise ratio metrics. Three medical test images such as one mammogram image, one angiogram image, and one thermal image are used in this paper. The Matlab R2018a tool is used to obtain the simulation results.

Keywords

• Dithering
• filtering
• half-toning
• MSE
• PSNR