Min-Kyu Park

Real-time digital zooming for mobile consumer cameras using directionally adaptive image interpolation and restoration

In this digest, we present a novel real-time digital zooming method based on directionally adaptive image interpolation and restoration. The proposed method first estimates an edge direction using steerable filters and performs weighted smoothing along the estimated edge direction. Bi-cubic and bi-linear interpolations are selectively used according to the estimated edge direction. Degradation and artifacts caused by interpolation are removed by employing a directionally adaptive truncated constrained least squares (TCLS) filter. The proposed digital zooming method followed by image restoration provides high-quality magnified images which are similar to the result of computationally intensive super-resolution algorithms. The proposed method can be applied to real-time image processing, and embedded in the form of the finite impulse response (FIR) filtering structure. It is suitable for digital zooming system of mobile phone cameras, tablet PCs, and digital camcorders.

61.1: Motion-Compensated Impulsive Driving Technique for LCD-TV

otion-estimation/motion-compensation (ME/MC) provides superior motion picture quality but its huge computation load results in high cost. Impulsive driving is a cost-effective solution but it suffers from large flicker and brightness loss. Motion compensated impulsive driving technology has been developed to achieve high motion picture quality in a cost-effective implementation by combining ME/MC and impulsive driving. The key idea is to apply ME/MC or impulsive driving selectively according to the motion vector distribution of the incoming image sequence. In this paper, the description of the algorithm and the experimental results are provided.

22.1: Low Power Driving Scheme for High Frame Rate LCD TVs

Recently, there have been lots of demands for green products. One of solutions is to reduce the power consumption. Whereas the most approaches in liquid crystal displays (LCDs) are focused on reduction of the backlight power consumption with local dimming technologies, this paper proposes the new low power driving scheme for LCD TV panels operated at high frame rates of 120Hz and 240Hz. Dynamic and static power consumptions have been lowered by means of the frame rate reduction for still input image and fallback and the charge sharing method applied at the vertical blank period. As the maximum, the total power can be reduced to around 50% and 75% for 120Hz and 240Hz.

Region adaptive color demosaicing using cross-channel correlation

In this paper, we consider the problem of recovering full-color images from color-sampled observation. Each pixel location is classified into flat, edge and pattern region and edge indicator function is used to avoid artifacts in high frequency regions and improve the performance. The horizontal and vertical direction of edge is decided using local statistics based on the concepts of spectral-spatial correlation. As a postprocessing, the modified filtering on color difference domain is adopted to improve the quality of the image. Experimental results illustrate the benefits of the proposed method. When compared to the conventional methods, the proposed method outperforms them on quantitative and qualitative criteria.

26.3: Motion Interpolation Performance of 120Hz Display Systems

120Hz driving using interpolated frames achieves better moving picture quality with less motion blur and less motion judder. However, errors in the interpolated frames can cause visual artifacts such as static text breakup, halos, and occlusions. This paper focuses on categorizing characteristics of visual artifacts and on reducing side-effects by using information from original frames in special cases.