Duk-Gyoo Kim

Image Adaptive Watermarking Technique for Digital Phone

Digital watermarking has been proposed as a solution to the problem of copyright protection of digital images in digital phone camera. There are two important issues that watermarking algorithms need to address. First, watermarking schemes are required to provide trustworthy evidence for protecting rightful ownership. Second, good watermarking schemes should satisfy the requirement of robustness and resist distortions due to common image manipulations. This paper presents a blind image watermarking scheme for camera phone. This method is based on singular value decomposition (SVD) and wavelet decomposition. Analysis and experimental results show that the proposed watermarking method performs well in security and robustness of digital phone camera

Dim moving target detection based on detection index using local gamma correction and motion information

This paper introduces a novel adaptive algorithm for target detection in infrared search and track (IRST) system. The algorithm is proposed on the basis of robust and adaptive method that is invariant to the prior uncertainty with respect to statistical properties of cluttered background and noise. The essence of proposed algorithm is to design the detection index over two images obtained by processing the given image through the local gamma correction (LGC) and the estimation of target motion. And the detection index (DI) is obtained by the two factors which calculated relations between two images: luminance rate (LR), and contrast rate (CR). Results of simulation show that the proposed algorithm gives an enormous gain on real infrared image sequences.

The feature vector selection for robust multiple face detection

This paper presents the robust feature vector selection for multiple frontal face detection based on the Bayesian statistical method. The feature vector for the training and classification are integrated by means, amplitude projections, and its 1D Harr wavelet of input image. And the statistical modeling is performed both for face and nonface classes. Finally, the estimated probability density functions (PDFs) are applied by the proposed Bayesian method to detect multiple frontal faces in an image. The proposed method can handle multiple faces, partially occluded faces, and slightly posed-angle faces. Especially, the proposed method is very effective for low quality face images. Experiments show that detection rate of the propose method is 98.3% with three false detections on SET3 testing data which have 227 faces in 80 images.

Efficient moving object segmentation algorithm for illumination change in surveillance system

An efficient algorithm to segment the moving object is very important in the surveillance system. In general, the change detection by comparing brightness value is a good and simple method, but it shows a poor performance under illumination change. Therefore, we propose the segmentation algorithm to extract effectively the object in spite of the illumination change. There are three modes to extract the object, the criteria of mode selection are both available background existence and illumination change. Then the object is finally obtained by using projection and the morphological operator in post-processing. Furthermore, the double binary method using the similarity of brightness value and spatial proximity is used to obtain more edge information. A good segmentation performance is demonstrated by the simulation result.

A Simple Estimation of the Rotation Parameter for the 2-Axes Stabilization System

The recent sight system requires high stabilization functions for the longer range of observation and the higher kill probability. To this end, it is necessary to compensate rotational disturbances which are not stabilized with the conventional 2-axes stabilization system. This paper proposes a simple method on the rotational motion estimation for the stabilization of the sight system.

A Novel Image Enhancement Algorithm for a Small Target Detection of Panoramic Infrared Imagery

A novel image enhancement algorithm that can efficiently detect a small target of panoramic infrared (IR) imagery is proposed. Image enhancement is the first step for detecting and recognizing a small target in the IR imagery. The essence of the proposed algorithm is to utilize the independent histogram equalization (HE) separately over two sub-images obtained by decomposing the given image through the statistical hypothesis testing (SHT). Experimental results show that the proposed algorithm has better discrimination and lower false alarm rate than the conventional algorithms.

In 0.7 Ga 0.3 As quantum-well MOSFETs with record g m and effective mobility

In this paper, we have fabricated and characterized In_0.7Ga_0.3As quantum-well (QW) MOSFETs with bi-layer Al₂O₃/HfO₂ gate stack, grown by ALD. The fabricated device with L_g = 4 μm exhibits excellent maximum transconductance (g_{m_max}) in excess of 0.5 mS/μm, together with reasonably good electrostatics integrity, such as DIBL <; 45 mV/dec and subthreshold swing <; 110 mV/dec. In addition, we have modeled a trend of g_{m_max} as a function of L_g, and benchmarked g_m characteristics of our InGaAs MOSFETs against other reports, revealing that the value of g_m demonstrated in this work is the highest among any other devices with similar values of L_g. In trying to understand how such performance comes from, we have extracted effective mobility, where the mobility in our devices is as high as 6,600 cm²/V-s at 300 K.

Super-resolution image enhancement by Papoulis-Gerchbergmethod improvement

This paper proposes super-resolution reconstruction algorithm for image enhancement. Super-resolution reconstruction algorithms reconstruct a high-resolution image from multi-frame low-resolution images of a scene. Conventional super- resolution reconstruction algorithms are iterative back-projection(IBP), robust super-resolution(RS)method and standard Papoulis-Gerchberg(PG)method. However, traditional methods have some problems such as rotation and ringing. So, this paper proposes modified algorithm to improve the problem. Experimental results show that this proposed algorithm solve the problem. As a result, the proposed method showed an increase in the PSNR for traditional super-resolution reconstruction algorithms.

Blind Image Watermarking Technique for Digital Phone Camera

In todays modern world, digital phone cameras are common daily gadgets that most people have and use. In the event of a traffic accident, a fire accident, or a criminal act, anyone will be able to capture these important moments and use authentic photographs for evidence purposes. Digital watermarking is able to ensure that the digital photographs taken are authentic and indeed taken from a particular phone camera. This paper presents a blind image watermarking technique for digital phone camera. This method is based on singular value decomposition (SVD) and wavelet decomposition. Experimental results show that the proposed technique performs well in security and robustness against JPEG compression.