Content-based Grayscale Image Colorization

This paper presents a new, effective and simple approach for grayscale image colorization. Based on human vision theories and digital signal analysis, image layers of different spatial frequencies would have different perceptual and physical (i.e. surface roughness) properties. Associating this concept with the classical color transfer technique of Welsh et al simplifies the colorization process when the image has no distinct texture or confusing luminance distribution. The results demonstrate the effectiveness of the proposed colorization scheme when compared with the classical Welsh et al colorization method for coloring a wide range of images including homogeneous and heterogeneous ones