Kyu-Ik Sohng

Small target detection using cross product based on temporal profile in infrared image sequences

This paper presents a new small target detection method using the cross product of the temporal pixels based on the temporal profile in infrared (IR) image sequences. The temporal characteristics of small targets and the various backgrounds are different. A new algorithm classifies target pixels and the background pixels through the hypothesis testing using the cross product of pixels on the temporal profile and predicts the temporal backgrounds based on the results. The small targets are detected by subtracting the predicted temporal background profile from the original temporal profile. For the performance comparison between the proposed algorithm and the conventional algorithms, the receiver operating characteristics (ROC) curves is computed in experiment. Experimental results show that the proposed algorithm has better discrimination and a lower false alarm rate than the conventional methods.

The Quantitative Model for Optimal Threshold and Gamma of Display Using Brightness Function

We investigated physical conditions for optimum display systems on various TV viewing conditions, and found that visual brightness function could be derived from relationships between Stevens power law and Bartleson-Brenemans brightness function, and that the optimum physical contrast ratio and compensated gamma for display system with adaptation luminance level could be obtained from the proposed brightness function.

Compensation of de-saturation effect in HDR imaging using a real scene adaptation model

The iCAM06, a high dynamic range rendering process, contains chromatic adaptation method based on the CIECAM02 model. The D factor, degree of adaptation, in the chromatic adaptation of the iCAM06 is the function of the adapting luminance level, but it does not consider the visual white point shift according to the variation of luminance level. The iCAM06 acquires a blurred illuminant image. So, each pixel has a different illuminant color. When some of the colors cover the entire image, a de-saturation effect appears around these colors. The simply modified D factor to reduce the de-saturation effect causes unsuitable changes in the degree of adaptation. Therefore, we propose a new method to find the global illuminant information and the D factor for the illuminant in the HDR image rendering process. Comparing the proposed with the conventional method, we confirm that the proposed method provides better illuminant estimation and color representation.

Implementation of a reticle seeker missile simulator for jamming effect analysis

In this paper, we implement a reticle seeker missile simulator on MATLAB-SIMULINK to analyze the jamming effect of the spin-scan and conscan reticle seeker. The DIRCM (Directed Infrared Countermeasures) system uses the pulsing flashes of infrared (IR) energy and its frequency and intensity have influence on the missile guidance system. Our simulation results show that jamming effect is indicated significantly when jammer frequency and reticle frequency are similar and present a 3D trajectory of missile motions by jamming.

A novel Two-Dimensional LMS (TDLMS) using sub-sampling mask and step-size index for small target detection

In this paper, we propose a novel TDLMS filter using a sub-sampling mask and step-size index for small target detection in infra-red (IR) imagery. The concept of the proposed TDLMS is to utilize the sub-sampling mask of the weight-matrix having the structure reducing effects of the target pixels in order to predict the background exactly. And the nonlinear step size using the luminance rate (LR) and contrast rate (CR) is used and then background is predicted finally by using the two-dimensional Gaussian distance (TDGD). Experimental results show that the proposed method exhibits higher detection rates in comparison to the conventional TDLMS filter.

Development of T-DMB system for mobile multimedia broadcasting service

We show the framework of the Korean terrestrial digital multimedia broadcasting (T-DMB) standard and propose the architecture of a new T-DMB system for mobile multimedia broadcasting services. We also designed and implemented a new device called the ensemble remultiplexer to verify the proposed T-DMB transmission system.

Recursive multi-SEs NWTH method for small target detection in infrared images

Mathematical morphology techniques, such as white top-hat (WTH) and new white top-hat (NWTH) transformation have been researched for small target detection application in the infrared (IR) images. However, its target enhancement performance still depends on its SE size set by users. To solve this problem, we propose a recursive multi-structuring elements (multi-SEs) NWTH method with an automatic decision mechanism of the SE size. The proposed method based on the NWTH transformation updates the multi-SEs by calculating candidate target-to-clutter ratio gain (CTCRG) of the NWTH images by the multi-SEs. Through a recursive procedure, final multi-SEs is automatically selected, and then small targets can be detected in a summation image of NWTH images by the final multi-SEs.

Development of a T-DMB extended WIPI platform for interactive mobile broadcasting services

In this paper, we present the architecture of the interactive terrestrial digital multimedia broadcasting (T-DMB) system using the code division multiple access (CDMA) network for the new interactive broadcasting services. We also propose the novel structure of the novel platform based on wireless Internet platform for interoperability (WIPI), which is the standard specifications for the mobile platform in Korea, to co-operate broadcasting and telecommunication. The proposed extended WIPI platform is implemented as an emulator on PC, and an integrated browser which shows multimedia broadcasting data including AV contents and interactive data returned through the telecommunication network, is developed to carry on with it. And then to verify the proposed platform and the interactive mobile broadcasting services, we implemented the integrated receiver as well as the data broadcasting server and the return channel server. Users can get interactive services or more information about broadcasting contents through CDMA network by using the proposed platform. This shows a possibility of new interactive services in digital broadcasting by using mobility of T-DMB and CDMA

DTV lip-sync test using time-indexed audio and video signals without effect on program

A new lip-synchronization (lip-sync) test method using audio and video signals for DTV is presented. The proposed method does not interfere with or have any effect on the program being broadcast, as the time-indexed lip-sync test signals (TILTS) are embedded in a hidden region. The video TILTS is embedded into transient effect areas outside the active pixel region, making it invisible on-screen. Experimental results confirm that the time difference between audio and video signals can be easily measured at any time from the TILTS in the decoder outputs.

Small target detection using the Bilateral Filter based on Target Similarity Index

This paper presents a new bilateral filter (BF)using the adaptive standard deviation based on the target similarity index (TSI) for small target detection. At first, the threshold value of pixels TSI in window decides whether any pixel is a potential small target or not. The TSIs of the potential small target pixels are mapped to standard deviations of domain and range filters of the BF by linear mapping and the two standard deviations increase in proportion to the TSI for blurring the small targets. For the more blurred small targets, the filter size according to the TSI is increased. Experimental results demonstrate that the proposed method is more robust and efficient than the conventional methods.