• Title/Summary/Keyword: Block-based difference image

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Smoke Detection using Block-based Difference Images and Projections (블록기반 차영상과 투영 그래프를 이용한 연기검출)

  • Kim, Dong-Keun;Kim, Won-Ho
    • The KIPS Transactions:PartB
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    • v.14B no.5
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    • pp.361-368
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    • 2007
  • In this paper, we propose a smoke detection method which is based on block-wise difference of image frames in video. Our proposed method is composed of three steps which are (a) the detection step of the changed regions against the background, (b) the background update step, and (c) the smoke determination step from the changed regions. We first construct the block mean Image of frames in video. And to extract the changed regions against the background, we use a block-wise difference between background's block mean image and a current input frame's block mean image. After applying projections in block-based difference images, we can determine the changed regions as rectangles using projections of difference images. we propose a update scheme of background's block mean image using the projections. We decide the smoke region using the femoral statistics of the central position and YUV color in the changed region.

Intermediate Image Generation of Stereo Image Using Depth Information and Block-based Matching Method (깊이정보와 블록기반매칭을 이용한 스테레오 영상의 중간영상 생성)

  • 양광원;허경무;김장기
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.10
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    • pp.874-880
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    • 2002
  • A number of techniques have been proposed for 3D display using view-difference of two eyes. These methods do not express enough reality like real world. The display images have to change according to the position of a viewer to improve reality. In this paper, we present an approach for generating intermediate image between two different view images by applying new image interpolation algorithm The interpolation algorithm is designed to cope with complex shapes. The proposed image interpolation algorithm generates rotated image about vertical axes by any angle from base images. Each base image that was obtained from CCD camera has an view-angle difference of $3^{\circ}C$, $5.5^{\circ}C$, $^{\circ}C$, $22^{\circ}C$, and $45^{\circ}C$. The proposed into mediate image generation method uses the geometric analysis of image and depth information through the block-based matching method.

A Texture Classification Based on LBP by Using Intensity Differences between Pixels (화소간의 명암차를 이용한 LBP 기반 질감분류)

  • Cho, Yong-Hyun
    • Journal of the Korean Institute of Intelligent Systems
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    • v.25 no.5
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    • pp.483-488
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    • 2015
  • This paper presents a local binary pattern(LBP) for effectively classifying textures, which is based on the multidimensional intensity difference between the adjacent pixels in the block image. The intensity difference by considering the a extent of 4 directional changes(verticality, horizontality, diagonality, inverse diagonality) in brightness between the adjacent pixels is applied to reduce the computation load as a results of decreasing the levels of histogram for classifying textures of image. And the binary patterns that is represented by the relevant intensities within a block image, is also used to effectively classify the textures by accurately reflecting the local attributes. The proposed method has been applied to classify 24 block images from USC Texture Mosaic #2 of 128*128 pixels gray image. The block images are different in size and texture. The experimental results show that the proposed method has a speedy classification and makes a free size block images classify possible. In particular, the proposed method gives better results than the conventional LBP by increasing the range of histogram level reduction as the block size becomes larger.

A Block Adaptive Bit Allocation for Progressive Transmission of Mean Difference Pyramid Image (Mean difference pyramid 영상의 점진적 전송을 위한 블록 적응 비트 배정)

  • 김종훈;신재범;심영석
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.4
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    • pp.130-137
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    • 1993
  • In this paper, A progressive coding of mean difference pyramid by Hadamard transform of the difference between two successive pyramid levels has been studied. A block adaptive bit allocation method based on ac energy of each sub-block has been proposed, which efficiently reduces the final distortion in the progressive transmission of image parameters. In our scheme, the dc energy equals the sum of the quantization errors of the Hadamard transform coefficients at previous level. Therefore proposed allocation method includes the estimation of dc energy at each pyramid level. Computer simulation results show some improvements in terms of MSE and picture quality over the conventional fixed allocation scheme.

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Fingerprint Image Quality Analysis for Knowledge-based Image Enhancement (지식기반 영상개선을 위한 지문영상의 품질분석)

  • 윤은경;조성배
    • Journal of KIISE:Software and Applications
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    • v.31 no.7
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    • pp.911-921
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    • 2004
  • Accurate minutiae extraction from input fingerprint images is one of the critical modules in robust automatic fingerprint identification system. However, the performance of a minutiae extraction is heavily dependent on the quality of the input fingerprint images. If the preprocessing is performed according to the fingerprint image characteristics in the image enhancement step, the system performance will be more robust. In this paper, we propose a knowledge-based preprocessing method, which extracts S features (the mean and variance of gray values, block directional difference, orientation change level, and ridge-valley thickness ratio) from the fingerprint images and analyzes image quality with Ward's clustering algorithm, and enhances the images with respect to oily/neutral/dry characteristics. Experimental results using NIST DB 4 and Inha University DB show that clustering algorithm distinguishes the image Quality characteristics well. In addition, the performance of the proposed method is assessed using quality index and block directional difference. The results indicate that the proposed method improves both the quality index and block directional difference.

The Study on the Medical Image Compression using the Characteristics of Human Visual System (인간 시각 장치의 특성을 이용한 의학 영상 압축에 관한 연구)

  • Chee, Young-Joon;Park, Kwang-Seok
    • Proceedings of the KOSOMBE Conference
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    • v.1993 no.05
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    • pp.38-41
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    • 1993
  • For efficient transmission and storage of digital images, the requirements of image compression is incresing. Because the medical images contain diagnostic information small distortion has been more important factor than the low rate in such images. Generally the distortion in image is the difference of pixel values. However the image is percieved by human visual systems. So it is reasonable that human visual system characteristics be used as criteria of the image compression. In this paper, the Just Noticeable Difference curve is used as criteria of determining the homogeniety of a block and acceptibility of distortions. And Block Truncation Coding using spatial masking effect of eyes is adopted to code the blocks which contain line components. And small blocks which varies slowly can be approximated to polynomial functions successfully. We proposed the hybrid block coding scheme based on the block characteristics and human visual system characteristics. Simulation to several kinds of the medical images using this method showed that medical images can be compressed 5:1 - 10:1 without noticeable distortion.

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Hiding Secret Data in an Image Using Codeword Imitation

  • Wang, Zhi-Hui;Chang, Chin-Chen;Tsai, Pei-Yu
    • Journal of Information Processing Systems
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    • v.6 no.4
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    • pp.435-452
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    • 2010
  • This paper proposes a novel reversible data hiding scheme based on a Vector Quantization (VQ) codebook. The proposed scheme uses the principle component analysis (PCA) algorithm to sort the codebook and to find two similar codewords of an image block. According to the secret to be embedded and the difference between those two similar codewords, the original image block is transformed into a difference number table. Finally, this table is compressed by entropy coding and sent to the receiver. The experimental results demonstrate that the proposed scheme can achieve greater hiding capacity, about five bits per index, with an acceptable bit rate. At the receiver end, after the compressed code has been decoded, the image can be recovered to a VQ compressed image.

Data Hiding in Halftone Images by XOR Block-Wise Operation with Difference Minimization

  • Yang, Ching-Nung;Ye, Guo-Cin;Kim, Cheon-Shik
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.5 no.2
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    • pp.457-476
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    • 2011
  • This paper presents an improved XOR-based Data Hiding Scheme (XDHS) to hide a halftone image in more than two halftone stego images. The hamming weight and hamming distance is a very important parameter affecting the quality of a halftone image. For this reason, we proposed a method that involves minimizing the hamming weights and hamming distances between the stego image and cover image in $2{\times}2$-pixel grids. Moreover, our XDHS adopts a block-wise operation to improve the quality of a halftone image and stego images. Furthermore, our scheme improves security by using a block-wise operation with A-patterns and B-patterns. Our XDHS method achieves a high quality with good security compared to the prior arts. An experiment verified the superiority of our XDHS compared with previous methods.

Smoke Detection Method of Color Image Using Object Block Ternary Pattern (물체 블록의 삼진 패턴을 이용한 컬러 영상의 연기 검출 방법)

  • Lee, Yong-Hun;Kim, Won-Ho
    • Journal of Satellite, Information and Communications
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    • v.9 no.4
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    • pp.1-6
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    • 2014
  • Color image processing based on smoke detection is suitable detecting target to early detection of fire smoke. A method for detecting the smoke is processed in the pre-processing movement and color. And Next, characteristics of smoke such as diffusion, texture, shape, and directionality are used to post-processing. In this paper, propose the detection method of density distribution characteristic in characteristics of smoke. the generate a candidate regions by color thresholding image in Detecting the movement of smoke to the 10Frame interval and accumulated while 1second image. then check whether the pattern of the smoke by candidate regions to applying OBTP(Object Block Ternary Pattern). every processing is Block-based processing, moving detection is decided the candidate regions of the moving object by applying an adaptive threshold to frame difference image. The decided candidate region accumulates one second and apply the threshold condition of the smoke color. make the ternary pattern compare the center block value with block value of 16 position in each candidate region of the smoke, and determine the smoke by compare the candidate ternary pattern and smoke ternary pattern.

Statistical Image Feature Based Block Motion Estimation for Video Sequences (비디오 영상에서 통계적 영상특징에 의한 블록 모션 측정)

  • Bae, Young-Lae;Cho, Dong-Uk;Chun, Byung-Tae
    • The Journal of the Korea Contents Association
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    • v.3 no.1
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    • pp.9-13
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    • 2003
  • We propose a block motion estimation algorithm based on a statistical image feature for video sequences. The statistical feature of the reference block is obtained, then applied to select the candidate starting points (SPs) in the regular starting points pattern (SPP) by comparing the statistical feature of reference block with that of blocks which are spread ower regular SPP. The final SPs are obtained by their Mean Absolute Difference(MAD) value among the candidate SPs. Finally, one of conventional fast search algorithms, such as BRGDS, DS, and three-step search (TSS), has been applied to generate the motion vector of reference block using the final SPs as its starting points. The experimental results showed that the starting points from fine SPs were as dose as to the global minimum as we expected.

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