• Journal of Information Processing Systems
• /
• 제13권2호
• /
• pp.340-347
• /
• 2017

A watermark is a signal added to the original signal in order to preserve the copyright of the owner of the digital content. The basic challenge for designing a watermarking system is a dilemma between transparency and robustness. If we want a higher rate of transparency, there has to be a compromise in terms of its robustness and vice versa. Also, until now, watermarking is generalized, resulting in the need for a specialized algorithm to work for a specialized image processing application domain. Our proposed technique takes into consideration the image characteristics for watermark insertion and it optimizes transparency and robustness. It achieved a 99.98% retrieval efficiency for an image blurring attack and counterfeits other attacks. Our proposed technique counterfeits almost all of the image processing attacks.

• 전기전자학회논문지
• /
• 제26권3호
• /
• pp.475-482
• /
• 2022

Signal pre-processing and post-processing are some areas of study around electrical resistance tomography due to the low spatial resolution of pixel-based reconstructed images. In addition, methods that improve integrity and noise reduction are candidates for application in ERT. Lately, formulations of image processing methods provide new implementations and studies to improve the response against noise. For example, compact variational mode decomposition has recently shown good performance in image decomposition and segmentation. The results from this first approach of C-VMD to ERT show an improvement due to image segmentation, providing filtering of noise in the background and location of the target.

• 융합신호처리학회논문지
• /
• 제12권2호
• /
• pp.91-95
• /
• 2011

In this paper, we present an improved multi-scale gradient algorithm. The proposed algorithm works the effectively handling of both step and blurred edges. In the proposed algorithm, the image sharpening operator is sharpening the edges and contours of the objects. This operation gives an opportunity to get noise reduced image and step edged image. After that, multi-scale gradient operator works on noise reduced image in order to get a gradient image. The gradient image is segmented by watershed transform. The approach of region merging is used after watershed transform. The region merging is carried out according to the region area and region homogeneity. The region number of the proposed algorithm is 36% shorter than that of the existing algorithm because the proposed algorithm produces a few irrelevant regions. Moreover, the computational time of the proposed algorithm is relatively fast in comparison with the existing one.

• 센서학회지
• /
• 제29권2호
• /
• pp.82-88
• /
• 2020

In this paper, we propose a complementary metal-oxide semiconductor (CMOS) binary image sensor with a gate/body-tied (GBT) p-channel metal-oxide-semiconductor field-effect transistor (PMOSFET)-type photodetector using a double-tail comparator for high-speed and low-power operations. The GBT photodetector is based on a PMOSFET tied with a floating gate (n+ polysilicon) and a body that amplifies the photocurrent generated by incident light. A double-tail comparator compares an input signal with a reference voltage and returns the output signal as either 0 or 1. The signal processing speed and power consumption of a double-tail comparator are superior over those of conventional comparator. Further, the use of a double-sampling circuit reduces the standard deviation of the output voltages. Therefore, the proposed CMOS binary image sensor using a double-tail comparator might have advantages, such as low power consumption and high signal processing speed. The proposed CMOS binary image sensor is designed and simulated using the standard 0.18 ㎛ CMOS process.

• 융합신호처리학회논문지
• /
• 제5권1호
• /
• pp.13-17
• /
• 2004

망막 촬영 및 다채널 고속 영상 획득 시스템을 개발하였다. 망막 두께 측정은 망막을 3차원으로 촬영하고 고속으로 신호처리를 할 수 있는 시스템을 요구한다. 망막에 레이저를 투사한 후에 반사되어 돌아오는 레이저의 양을 array photo diode를 이용하여 감지하며 이를 3차원 영상화하여 망막의 두께를 측정할 수 있다. 망막에 레이저를 투사하는 장치, APD 광센서를 이용한 망막 영상화 장치, 다채널 고속 A/D 변환장치 및 PCI 인터페이스를 개발하였다. polygon mirror와 galvano mirror를 이용하여 HeNe 레이저 빔을 각각 수평방향과 수직방향으로 주사하여 이미지 평면을 만들어 망막에 투사하였다. APD 어레이 광센서를 이용하여 각 층별로 나타나는 망막영상을 획득하였으며, 이를 실시간으로 A/D 변환하여 PCI 버스를 통해 컴퓨터로 전송하였다.

• 대한원격탐사학회:학술대회논문집
• /
• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
• /
• pp.526-529
• /
• 2007

Due to its inherent feature of high-resolution satellite, there is strong need in some specific area to minimize the processing time required to get a standard image on hand from downlink signal acquisition. However, in general image processing system, it takes considerable time to get image data up to certain level from raw data acquisition because the huge amount of data is dealt sequentially as input data. This paper introduces the high-speed image processing system which generates the image data only for the area selected by user. To achieve the high speed performance, this system includes Quick Look Image display function with sampling, ROI selection function, Image Line Index function, and Distributed processing function. The developed RPS was applied to KOMPSAT-2 320Mbps downlink channel and its effectiveness was successfully demonstrated. This feature to provide the image product very quickly is expected to promote the application of high resolution satellite image.

• 반도체디스플레이기술학회지
• /
• 제21권4호
• /
• pp.92-98
• /
• 2022

This paper proposes a new method of the traffic signal detection and the recognition in an HSI color model. The proposed method firstly converts a ROI image in the RGB model to in the HSI model to segment the color of a traffic signal. Secondly, the segmented colors are dilated by the morphological processing to connect the traffic signal light and the signal light case and finally, it extracts the traffic signal light and the case by the aspect ratio using the connected component analysis. The extracted components show the detection and the recognition of the traffic signal lights. The proposed method is implemented using C language in Raspberry Pi 4 system with a camera module for a real-time image processing. The system was fixedly installed in a moving vehicle, and it recorded a video like a vehicle black box. Each frame of the recorded video was extracted, and then the proposed method was tested. The results show that the proposed method is successful for the detection and the recognition of traffic signals.

• 대한전자공학회:학술대회논문집
• /
• 대한전자공학회 2003년도 하계종합학술대회 논문집 Ⅲ
• /
• pp.1685-1688
• /
• 2003

The modem multimedia applications which are video Processor, video conference or video phone and so forth require real time processing. Because of a large amount of image data, those require high compression performance. In this paper, the proposed image processing encoder was designed by using wavelet transform encoding. The proposed filter block can process image data on tile high speed because of composing individual function blocks by parallel and compute both highpass and lowpass coefficient in the same clock cycle. When image data is decomposed into multiresolution, the proposed scheme needs external memory and controller to save intermediate results and it can operate within 33㎒.

• Journal of Information Processing Systems
• /
• 제1권1호
• /
• pp.32-35
• /
• 2005

Image denoising is basic work for image processing, analysis and computer vision. This paper proposes a novel algorithm based on wavelet threshold for image denoising, which is combined with the linear CLS (Constrained Least Squares) filtering and thresholding methods in the transform domain. We demonstrated through simulations with images contaminated by white Gaussian noise that our scheme exhibits better performance in both PSNR (Peak Signal-to-Noise Ratio) and visual effect.

• 한국멀티미디어학회논문지
• /
• 제9권11호
• /
• pp.1455-1464
• /
• 2006

본 논문에서는 컬러 이미지에 적합한 화질 향상 알고리듬을 제안 하였다. 제안된 알고리듬은 입력 이미지의 명도 향상을 위한 MIE기법과 채도 향상을 위한 MSE기법으로 구분된다. MIE기법은 휘도 신호 처리 시 발생하는 색 재현 문제 및 과도한 밝기 변화를 제어하기 위한 알고리듬이고, MSE기법은 색차 신호 처리 시 발생하는 De-Saturation 혹은 Over-Saturation의 발생을 제어하기 위한 알고리듬이다. 제안된 알고리듬은 인간의 시각선호색을 중심으로 연산하며, 전체 이미지에 균등하게 적용하는 것 보다 고품질의 이미지를 얻을 수 있다. 제안한 알고리듬은 고화질을 위한 모니터나 TV등의 디스플레이 장치에 적용 가능하다.