• Title/Summary/Keyword: Wavelet video

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Implementation of Intelligent Image Surveillance System based Context (컨텍스트 기반의 지능형 영상 감시 시스템 구현에 관한 연구)

  • Moon, Sung-Ryong;Shin, Seong
    • Journal of the Institute of Electronics Engineers of Korea SP
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    • v.47 no.3
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    • pp.11-22
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    • 2010
  • This paper is a study on implementation of intelligent image surveillance system using context information and supplements temporal-spatial constraint, the weak point in which it is hard to process it in real time. In this paper, we propose scene analysis algorithm which can be processed in real time in various environments at low resolution video(320*240) comprised of 30 frames per second. The proposed algorithm gets rid of background and meaningless frame among continuous frames. And, this paper uses wavelet transform and edge histogram to detect shot boundary. Next, representative key-frame in shot boundary is selected by key-frame selection parameter and edge histogram, mathematical morphology are used to detect only motion region. We define each four basic contexts in accordance with angles of feature points by applying vertical and horizontal ratio for the motion region of detected object. These are standing, laying, seating and walking. Finally, we carry out scene analysis by defining simple context model composed with general context and emergency context through estimating each context's connection status and configure a system in order to check real time processing possibility. The proposed system shows the performance of 92.5% in terms of recognition rate for a video of low resolution and processing speed is 0.74 second in average per frame, so that we can check real time processing is possible.

An Empirical Digital Image Watermarking using Frequency Properties of DWT (DWT의 주파수 특성을 이용한 실험적 디지털 영상 워터마킹)

  • Kang, I-Seul;Lee, Yong-Seok;Seob), Young-Ho;Kim, Dong-Wook
    • Journal of Broadcast Engineering
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    • v.22 no.3
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    • pp.295-312
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    • 2017
  • Digital video content is the most information-intensive and high-value content. Therefore, it is necessary to protect the intellectual property rights of these contents, and this paper also proposes a watermarking method of digital image for this purpose. The proposed method uses the frequency characteristics of 2-Dimensional Discrete Wavelet Transform (2D-DWT) for digital images and digital watermark on global data without using local or specific data of the image for watermark embedding. The method to insert digital watermark data uses a simple Quantization Index Modulation (QIM) and a multiple watermarking method that inserts the same watermark data in multiple. When extracting a watermark, multiple watermarks are extracted and the final watermark data is determined by a simple statistical method. This method is an empirical method for experimentally determining the parameters in the watermark embedding process. The proposed method performs experiments on various images against various attacks and shows the superiority of the proposed method by comparing the performance with the representative existing methods.

Effective MCTF based on Correlation Improvement of Motion Vector Field (움직임 벡터 필드의 상관도 향상을 통한 효과적인 MCTF 방법)

  • Kim, Jongho
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.18 no.5
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    • pp.1187-1193
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    • 2014
  • This paper presents an effective motion estimation to improve the performance of the motion compensated temporal filtering (MCTF) which is a core part of the wavelet-based scalable video coding. The proposed scheme makes the motion vector field uniform by the modified median operation and the search strategies using adjacent motion vectors, in order to enhance the pixel connectivity which is significantly relevant to the performance of the MCTF. Moreover, the motion estimation with variable block sizes that reflects the features of frames is introduced for further correlation improvement of the motion vector field. Experimental results illustrate that the proposed method reduces the decomposed energy on the temporal high frequency subband frame up to 30.33% in terms of variance compared to the case of the full search with fixed block sizes.

Extraction of Features in key frames of News Video for Content-based Retrieval (내용 기반 검색을 위한 뉴스 비디오 키 프레임의 특징 정보 추출)

  • Jung, Yung-Eun;Lee, Dong-Seop;Jeon, Keun-Hwan;Lee, Yang-Weon
    • The Transactions of the Korea Information Processing Society
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    • v.5 no.9
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    • pp.2294-2301
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    • 1998
  • The aim of this paper is to extract features from each news scenes for example, symbol icon which can be distinct each broadcasting corp, icon and caption which are has feature and important information for the scene in respectively, In this paper, we propose extraction methods of caption that has important prohlem of news videos and it can be classified in three steps, First of al!, we converted that input images from video frame to YIQ color vector in first stage. And then, we divide input image into regions in clear hy using equalized color histogram of input image, In last, we extracts caption using edge histogram based on vertical and horizontal line, We also propose the method which can extract news icon in selected key frames by the difference of inter-histogram and can divide each scene by the extracted icon. In this paper, we used comparison method of edge histogram instead of complex methcxls based on color histogram or wavelet or moving objects, so we shorten computation through using simpler algorithm. and we shown good result of feature's extraction.

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A differential image quantizer based on wavelet for low bit rate video coding (저비트율 동영상 부호화에 적합한 웨이블릿 기반의 차영상 양자화기)

  • 주수경;유지상
    • Journal of Broadcast Engineering
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    • v.8 no.4
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    • pp.473-480
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    • 2003
  • In this paper, we propose a new quadtree coding a1gorithm to improve the performance of the old one. The new algorithm can process any frame of size in standard and reduce encoding and decoding time by decreasing computational load. It also improves the image quality comparing with any old quantizer based on quadtree and zerotree structure. In order for the new algorithm to be applied for real video codec, we analyze the statistical characteristics of coefficients of differential image and add a function that makes It deal with an arbitrary size of image by using new technique while the old one process by block unit. We can also improve the image quality by scaling the coefficient's value from a differential image. By comparing the performance of the new algorithm with quadtree and SPIHT, it Is shown that PSNR is improved, that the computational load is not reduced in encoding and decoding.

Multi-resolution Motion Estimation Algorithm Using Adaptive Search Region (적응적 탐색영역을 이용한 다중해상도 움직임 추정 방법)

  • 최정현;이경환;이법기;정원식;정태연;김덕규
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.24 no.8B
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    • pp.1540-1548
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    • 1999
  • We propose a multi-resolution motion estimation algorithm using adaptive search region. It is constructed in wavelet domain that a binary plane which represents the potential motion areas(PMA's) based on the temporal redundancy between video frames, and motion estimation is processed in the PMA's. We reduce the PMA's gradually as the resolution level is higher, considering the distribution of the energy in subband layers and the complexity. As compared with EMRME(enhanced multi-resolution motion estimation) method[7], simulation results show that computational amount and bit rate reduced to about 33 ~46 % and 10 ~l8% respectively in active image with similar PSNR, and computational amount reduced to about 37 ~65 % in small notion image with similar PSNR and bit rate.

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Fast Hybrid Transform: DCT-II/DFT/HWT

  • Xu, Dan-Ping;Shin, Dae-Chol;Duan, Wei;Lee, Moon-Ho
    • Journal of Broadcast Engineering
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    • v.16 no.5
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    • pp.782-792
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    • 2011
  • In this paper, we address a new fast DCT-II/DFT/HWT hybrid transform architecture for digital video and fusion mobile handsets based on Jacket-like sparse matrix decomposition. This fast hybrid architecture is consist of source coding standard as MPEG-4, JPEG 2000 and digital filtering discrete Fourier transform, and has two operations: one is block-wise inverse Jacket matrix (BIJM) for DCT-II, and the other is element-wise inverse Jacket matrix (EIJM) for DFT/HWT. They have similar recursive computational fashion, which mean all of them can be decomposed to Kronecker products of an identity Hadamard matrix and a successively lower order sparse matrix. Based on this trait, we can develop a single chip of fast hybrid algorithm architecture for intelligent mobile handsets.

Postprocessing in Block-Based Video Coding Based on a Quantization Noise Model (양자화 잡음 모델에 근거한 블록기반 동영상 부호화에서의 후처리)

  • 문기웅;장익훈;김남철
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.26 no.8B
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    • pp.1129-1140
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    • 2001
  • 본 논문에서는 블록기반 동영상 부호화에서 나타나는 양자화 잡음을 그 특성에 맞게 모델링을 하고, 이를 기반으로 웨이블렛 변환(wavelet transform)을 이용하여 양자화 잡음을 제거하는 후처리 방법을 제안한다. 제안된 방법에서는 양자화 잡음을 특정 프로화일(profile)로 표현되는 블록화 잡음과 비에지 화소(non-edge pixel)에서 백색 가우시안 특성을 가지는 나머지 잡음의 합으로 모델링 한다. 이러한 양자화 잡음의 모델을 기반으로 정칙화 미분(regularized differentiation)을 표현하는 Mallat의 1차원 웨이브렛 변환을 이용하여 영상복원 관점에서 각각의 잡음을 제거한다. 먼저, 웨이브렛 영역의 블록경계에서 임펄스로 나타나는 블록화 잡음 성분들의 크기를 추정하여 줄임으로 해서 블록화 잡음을 제거한다. 이때 임펄스 크기의 추정은 메디안 필터와 양자화 파라미터(quantization parameter), 그리고 국부 활동도(local activity)를 이용하여 이루어진다. 그리고 나머지 잡음은 비에지 화소에서 연역치화(soft-thresholding)을 수행함으로써 제거한다. 이러한 후처리 방법의 구현은 실시간 응용을 위해 웨이브렛 필터를 이용하여 근사적으로 공간 영역에서 이루어진다. 실험 결과, 제안된 방법이 다양한 영상과 압축률에 대해 MPEG-4 VM(verification model) 후처리 필터(post-filter)보다 PSNR 성능뿐만 아니라 주관적 화질면에서도 우수함을 확인하였다.

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A Study on Low-Band-Shift with Integer Lifting for Effective Motion Estimation (효과적인 움직임 예측을 위한 정수형 리프팅 기반의 저대역 이동법에 관한 연구)

  • Baek, Jung-Eun;Jang, Sun-Bong;Shin, Jong-Hong;Jee, Inn-Ho
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.10C
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    • pp.948-955
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    • 2006
  • In this paper, we propose motion estimation and compensation using Low-Band-Shift(LBS) with Integer Lifting Shift property. To overcome shift-variant property on wavelet coefficients, the LBS was previously proposed. This method which is applied to reference frame in video coding technique has superior performance in terms of rate-distortion characteristic. However, this method needs more memory and computational complexity. For the enhancement of those disadvantages, we propose motion estimation using Low-Band-Shift with Integer Lifting. The Integer Lifting implementation gives us good efficiency of calculation and storage.

Contents Adaptive MCTF Using JND (JND를 이용한 적응적 MCTF)

  • Heo, Jae-Seong;Ryu, Chul
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.34 no.1C
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    • pp.48-55
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    • 2009
  • In scalable video coding, MCTF plays an important role for time-scalability and SNR-scalability. But there is image quality decreasing as MCTF level is increased because time interval of each frame is extended so that is hard to find suitable motion vector. In this paper, we propose an algorithm to prevent image quality from decreasing with unsuitable motion vector during MCTF update process using JND. We adapt JND to find errors within blocks of image and set a threshold which is used to add high frequency components during update process. We can overcome time-gap between frames and achieve better image quality through the proposed algorithm.