Fast Color Removal Method Considering Differences between Colors

When a color image is converted into a monochrome one, luminance components of the pixels have been used as gray-levels for the representation of the monochrome image in HDTV standard. However, saliencies of the image embedded only in the chrominance components are disappeared in the monochrome image converted by using luminance components. To cope with this problem, A.A. Gooch et al. have proposed the salience-preserving color removal method called “Color2Gray.” The monochrome image well reected the impression of an input color image can be yielded by Color2Gray. However, the calculation cost of that algorithm is tremendous, and its utility is not so much. In this paper, fast Color2Gray algorithms are proposed. The effectiveness of the proposed method is illustrated through the experiments

Multiscale Retinex with Data-dependent Offset

As one of methods to improve the image quality, there is a method called multiscale retinex (MSR) which has been proposed by D.J. Jobson et al. In MSR, the reection components of an image are extracted and emphasized, and then the image with improved quality is obtained. This method is very useful and powerful especially for the visibility improvement of dark regions of the image. However, the resulting image tends to give us the unnatural impression because luminance components are removed, and the global contrast of the image is decreased in the processing. In this paper, a new MSR with a variable offset, which changes dependently on the local luminance information of the image, is proposed in order to overcome the disadvantage of the conventional MSR, and to further improve the image quality. Through the experiments, the effectiveness of the proposed method is illustrated

Tissue Characterization of Coronary Plaque by Using Fractal Analysis-based Features of IVUS RF-signal

We propose a precise tissue characterization method of coronary plaque by using fractal analysis-based features which are obtained from radiofrequency (RF) signal employing intravascular ultrasound (IVUS) method. The IVUS method is used for the diagnosis of the acute coronary syndromes (ACS). In the proposed method, the fact that the RF signal reflects the complexity of the structure of tissue is used. The effectiveness of the proposed method is verified through a series of experiments by using IVUS RF signals obtained from a rabbit and a human patient

Image enlargement with high-frequency component augmentation based on predefined codebook describing edge blurring properties

Image super-resolution as high-quality image enlargement is achieved by some type of restoration for high-frequency components that deteriorate through the image enlargement. The estimation methods using the given image itself are effective for the restoration, and we have proposed a method employing the codebook describing edge blurring properties that are derived from the given image. It is, however, unfavourable to apply those image-dependent methods to movies whose scene varies momentarily. In this paper, an image-independent codebook incorporating local edge patterns of images is proposed, and then the predefined codebook is applied. The effectiveness is shown through some experiments

Chroma Enhancement in CIELAB Color Space Using a Lookup Table

In this study, we present a method of chroma enhancement in the CIELAB color space and compare it with that in the RGB color space. Color image enhancement using the CIELAB color space has the disadvantage that the color gamut problem occurs because the conversion to the RGB color space is necessary to display the image. However, since the CIELAB color space is based on human visual perception, the quality of the resulting images is expected to be higher than that of the RGB color space. In the method using the CIELAB color space, we introduce a lookup table to reduce the calculation costs. Experiments comparing image enhancement results obtained from two color spaces are performed using several digital images

Fast Color Removal Method Considering Differences between Colors

Abstract-When a color image is converted into a monochrome one, luminance components of the pixels have been used as gray-levels for the representation of the monochrome image in HDTV standard. However, saliencies of the image embedded only in the chrominance components are disappeared in the monochrome image converted by using luminance components. To cope with this problem, A.A. Gooch et al. have proposed the salience-preserving color removal method called "Color2Gray." The monochrome image well reflected the impression of an input color image can be yielded by Color2Gray. However, the calculation cost of that algorithm is tremendous, and its utility is not so much. In this paper, fast Color2Gray algorithms are proposed. The effectiveness of the proposed method is illustrated through the experiments

Multiscale Retinex with Data-dependent Offset

As one of methods to improve the image quality, there is a method called multiscale retinex (MSR) which has been proposed by D.J. Jobson et al. In MSR, the reflection components of an image are extracted and emphasized, and then the image with improved quality is obtained. This method is very useful and powerful especially for the visibility improvement of dark regions of the image. However, the resulting image tends to give us the unnatural impression because luminance components are removed, and the global contrast of the image is decreased in the processing. In this paper, a new MSR with a variable offset, which changes dependently on the local luminance information of the image, is proposed in order to overcome the disadvantage of the conventional MSR, and to further improve the image quality. Through the experiments, the effectiveness of the proposed method is illustrated