• Title/Summary/Keyword: Chrominance

Search Result 111, Processing Time 0.021 seconds

Block Truncation Coding using Reduction Method of Chrominance Data for Color Image Compression (색차 데이터 축소 기법을 사용한 BTC (Block Truncation Coding) 컬러 이미지 압축)

  • Cho, Moon-Ki;Yoon, Yung-Sup
    • Journal of the Institute of Electronics Engineers of Korea SD
    • /
    • v.49 no.3
    • /
    • pp.30-36
    • /
    • 2012
  • block truncation coding(BTC) image compression is known as a simple and efficient technology for image compression algorithm. In this paper, we propose RMC-BTC algorithm(RMC : reduction method chrominace data) for color image compression. To compress chrominace data, in every BTC block, the RMC-BTC coding employs chrominace data expressed with average of chrominace data and using method of luminance data bit-map to represented chrominance data bit-map. Experimental results shows efficiency of proposed algorithm, as compared with PSNR and compression ratio of the conventional BTC method.

Face Detection Based on Distribution Map (분포맵에 기반한 얼굴 영역 검출)

  • Cho Han-Soo
    • Journal of Korea Multimedia Society
    • /
    • v.9 no.1
    • /
    • pp.11-22
    • /
    • 2006
  • Recently face detection has actively been researched due to its wide range of applications, such as personal identification and security systems. In this paper, a new face detection method based on the distribution map is proposed. Face-like regions are first extracted by applying the skin color map with the frequency to a color image and then, possible eye regions are determined by using the pupil color distribution map within the face-like regions. This enables the reduction of space for finding facial features. Eye candidates are detected by means of a template matching method using weighted window, which utilizes the correlation values of the luminance component and chrominance components as feature vectors. Finally, a cost function for mouth detection and location information between the facial features are applied to each pair of the eye candidates for face detection. Experimental results show that the proposed method can achieve a high performance.

  • PDF

Fast Video Fire Detection Using Luminous Smoke and Textured Flame Features

  • Ince, Ibrahim Furkan;Yildirim, Mustafa Eren;Salman, Yucel Batu;Ince, Omer Faruk;Lee, Geun-Hoo;Park, Jang-Sik
    • KSII Transactions on Internet and Information Systems (TIIS)
    • /
    • v.10 no.12
    • /
    • pp.5485-5506
    • /
    • 2016
  • In this article, a video based fire detection framework for CCTV surveillancesystems is presented. Two novel features and a novel image type with their corresponding algorithmsareproposed for this purpose. One is for the slow-smoke detection and another one is for fast-smoke/flame detection. The basic idea is slow-smoke has a highly varying chrominance/luminance texture in long periods and fast-smoke/flame has a highly varying texture waiting at the same location for long consecutive periods. Experiments with a large number of smoke/flame and non-smoke/flame video sequences outputs promising results in terms of algorithmic accuracy and speed.

Surface Appearance of Galvanized Steel with Outdoor Exposure Testing in Korea for 36 Months (36개월간 국내 옥외폭로시험에 따른 아연도강의 표면외관 변화)

  • Kim, K.T.;Kim, Y.S.
    • Corrosion Science and Technology
    • /
    • v.17 no.6
    • /
    • pp.301-309
    • /
    • 2018
  • If galvanized steel is exposed to an outdoor environment, atmospheric corrosion will occur with time and red rust will form when the sacrificial protection capacity of zinc reaches its limit. With corrosion, the surface appearance of steel changes, and the properties of the exterior materials degrade. In this study, two kinds of galvanized steel, (GA and GI specimens) were subjected to an outdoor exposure test for 36 months in six regions of Korea. Chrominance (color, chroma, and brightness) and glossiness surface analyses were performed. The color change was not significant, regardless of the exposed area or the specimens tested. With increasing exposure times, the GA specimen became blackened by the formation of zinc oxide, and red coloration was increased by the formation of red rust. As the exposure time of GI specimen increased, the surface proceeded to blacken, but no red rust was formed and the color did not change significantly. Regardless of the outdoor exposure area or the specimen, longer exposure times led to lower glossiness, and this behavior appears to be influenced by the formation of zinc oxide.

New Prefiltering Methods based on a Histogram Matching to Compensate Luminance and Chrominance Mismatch for Multi-view Video (다시점 비디오의 휘도 및 색차 성분 불일치 보상을 위한 히스토그램 매칭 기반의 전처리 기법)

  • Lee, Dong-Seok;Yoo, Ji-Sang
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.47 no.6
    • /
    • pp.127-136
    • /
    • 2010
  • In multi-view video, illumination disharmony between neighboring views can occur on account of different location of each camera and imperfect camera calibration, and so on. Such discrepancy can be the cause of the performance decrease of multi-view video coding by mismatch of inter-view prediction which refer to the pictures obtained from the neighboring views at the same time. In this paper, we propose an efficient histogram-based prefiltering algorithm to compensate mismatches between the luminance and chrominance components in multi-view video for improving its coding efficiency. To compensate illumination variation efficiently, all camera frames of a multi-view sequence are adjusted to a predefined reference through the histogram matching. A Cosited filter that is used for chroma subsampling in many video encoding schemes is applied to each color component prior to histogram matching to improve its performance. The histogram matching is carried out in the RGB color space after color space converting from YCbCr color space. The effective color conversion skill that has respect to direction of edge and range of pixel value in an image is employed in the process. Experimental results show that the compression ratio for the proposed algorithm is improved comparing with other methods.

Two dimensional filter design for HDTV (고화질 텔레비젼용 이차원 필터 설계)

  • 박주성;윤병우;제영호;양진영;박종철;심영석
    • Journal of the Korean Institute of Telematics and Electronics A
    • /
    • v.31A no.10
    • /
    • pp.152-160
    • /
    • 1994
  • Two dimensional interpolation filter for HD-MAC is designed with 1.0 .mu.m CMOS standard cells and verified by logic simulation. The interpolator uses FMH(FIR-Median Hybrid) filter. The median filter, which is the most complicated part of FMH filtre, is simply implemented by modifying Hadian-Sobel algorithm. the filter generates accurately the missed pixel data of luminance and chrominance with the worst case simulation condition at 27MHz clock rates.

  • PDF

Non-linear Interpolation for Color Images

  • Kim, Jong-Ho;Kim, Won-Ki;Yeom, Dong-Hyun;Jeong, Je-Chang
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2006.08a
    • /
    • pp.1326-1329
    • /
    • 2006
  • In this paper, we propose a non-linear interpolation of chrominance components based on the property of luminance signals to display color images effectively. The proposed method is more useful, in particular, for the images including stair-typed signal changes around edges. Experimental results show that the proposed method is superior to conventional methods in both objective and subjective performance.

  • PDF

Color Demosaicing Algorithm Considering Color Constancy (색의 일관성을 고려한 색상 보간)

  • Kim, Chang-Won;Oh, Hyun-Mook;Kang, Moon-Gi
    • Journal of the Institute of Electronics Engineers of Korea SP
    • /
    • v.47 no.3
    • /
    • pp.1-10
    • /
    • 2010
  • In this paper, we propose a novel way of combining color demosaicing and the auto white balance (AWB) method, which are important parts of image processing. Performance of the AWB is generally affected by demosaicing results because most AWB algorithms are performed posterior to color demosaicing. In order to increase the performance and efficiency of the AWB algorithm, the color constancy problem is considered during the color demosaicing step. Initial estimates of the directional luminance and chrominance values are defined for estimating edge direction and calculating the AWB gain. We propose a modified edge-based AWB method that used a pre-defined achromatic region. The estimation of edge direction is performed region adaptively by using the local statistics of the initial estimates of the luminance and chrominance information. The proposed method shows significant improvements in terms of visual and numerical criteria when compared to conventional methods.

An Efficient Color Interpolation Method for Color Filter Array (색상 필터 배열을 위한 효율적인 색상 보간 방법)

  • Cho, Yang-Ki;Kim, Hi-Seok
    • Journal of the Institute of Electronics Engineers of Korea CI
    • /
    • v.43 no.6 s.312
    • /
    • pp.92-100
    • /
    • 2006
  • In imaging devices such as digital cameras using a single image sensor, captured images are the sub-sampled images comprised of the pixels that have only one of the three primary colors per a pixel. This images should be restored to the color images through an image processing referred as color interpolation. In this paper, we derive relation between the average of the data from CFA image sensor and the average of each color channel data. By using this relation, a new efficient method for color interpolation is proposed. Also, in order to reduce the zipper effect in a restored image, missing luminance values are interpolated along any edges in the captured image. On the other hand, for the chrominance channel interpolation, we average difference between a chrominance value and a luminance value in a local area, and this average value is added to the pixel value of the interpolated location. The proposed method has been compared with several previous methods, and our experimental results show the better results than the other methods.

Face Region Detection using a Color Union Model and The Levenberg-Marquadt Algorithm (색상 조합 모델과 LM(Levenberg-Marquadt)알고리즘을 이용한 얼굴 영역 검출)

  • Kim, Jin-Ok
    • The KIPS Transactions:PartB
    • /
    • v.14B no.4
    • /
    • pp.255-262
    • /
    • 2007
  • This paper proposes an enhanced skin color-based detection method to find a region of human face in color images. The proposed detection method combines three color spaces, RGB, $YC_bC_r$, YIQ and builds color union histograms of luminance and chrominance components respectively. Combined color union histograms are then fed in to the back-propagation neural network for training and Levenberg-Marquadt algorithm is applied to the iteration process of training. Proposed method with Levenberg-Marquadt algorithm applied to training process of neural network contributes to solve a local minimum problem of back-propagation neural network, one of common methods of training for face detection, and lead to make lower a detection error rate. Further, proposed color-based detection method using combined color union histograms which give emphasis to chrominance components divided from luminance components inputs more confident values at the neural network and shows higher detection accuracy in comparison to the histogram of single color space. The experiments show that these approaches perform a good capability for face region detection, and these are robust to illumination conditions.