Scientific Research and Essays

  • Abbreviation: Sci. Res. Essays
  • Language: English
  • ISSN: 1992-2248
  • DOI: 10.5897/SRE
  • Start Year: 2006
  • Published Articles: 2767

Full Length Research Paper

A novel adaptive color to grayscale conversion algorithm for digital images

Wei Hong Lim and Nor Ashidi Mat Isa*
Email: [email protected]

  •  Accepted: 06 July 2012
  •  Published: 31 August 2012




A color image sent to the monochrome device must undergo the color-to-grayscale conversion process. Although the conventional color-to-grayscale conversion algorithms are widely used, their performance is questionable in certain circumstances and poor quality resultant grayscale images will be produced. This paper tackled some drawbacks of the conventional methods by introducing a novel approach namely the Adaptive Color to Grayscale (ACGS) conversion algorithm. In the proposed ACGS method, the pixels distribution analysis of input color images was performed to calculate the weight contribution of red, green, and blue components during the conversion process. The extensive experimental results demonstrated the superior qualitative and quantitative performance of the proposed ACGS method over the conventional algorithms and its feasibility in real-time video processing applications. These promising results suggest that the proposed ACGS method is suitable to be employed in the monochrome devices for pre- and post- processing of digital images.


Key words: Color-to-grayscale conversion, adaptive, color image, grayscale image, image pre-processing.




Abbreviations: 2-D, Two-dimensional; 3-D, three dimensional; ACGS, adaptive color to grayscale; AE, average entropy; AMI, average mean intensity; ASD,average standard deviation; E, entropy; HSV, human visual system; MI, mean intensity; NTSC, national television system committee; PDF, probability density function; RGB, red, green, and blue; SD, standard deviation.