• Title/Summary/Keyword: Video Projection

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An Efficient Video Retrieval Algorithm Using Luminance Projection

  • Kim, Sang-Hyun
    • Journal of the Korean Data and Information Science Society
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    • v.15 no.4
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    • pp.891-898
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    • 2004
  • An effective video indexing is required to manipulate large video databases. Most algorithms for video indexing have been commonly used histograms, edges, or motion features. In this paper, we propose an efficient algorithm using the luminance projection for video retrieval. To effectively index the video sequences and to reduce the computational complexity, we use the key frames extracted by the cumulative measure, and compare the set of key frames using the modified Hausdorff distance. Experimental results show that the proposed video indexing and video retrieval algorithm yields the higher accuracy and performance than the conventional algorithm.

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A Method for Identification of Harmful Video Images Using a 2-Dimensional Projection Map

  • Kim, Chang-Geun;Kim, Soung-Gyun;Kim, Hyun-Ju
    • Journal of information and communication convergence engineering
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    • v.11 no.1
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    • pp.62-68
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    • 2013
  • This paper proposes a method for identification of harmful video images based on the degree of harmfulness in the video content. To extract harmful candidate frames from the video effectively, we used a video color extraction method applying a projection map. The procedure for identifying the harmful video has five steps, first, extract the I-frames from the video and map them onto projection map. Next, calculate the similarity and select the potentially harmful, then identify the harmful images by comparing the similarity measurement value. The method estimates similarity between the extracted frames and normative images using the critical value of the projection map. Based on our experimental test, we propose how the harmful candidate frames are extracted and compared with normative images. The various experimental data proved that the image identification method based on the 2-dimensional projection map is superior to using the color histogram technique in harmful image detection performance.

Luminance Projection Model for Efficient Video Similarity Measure (효율적인 비디오 유사도 측정을 위한 휘도 투영모델)

  • Kim, Sang-Hyun
    • Journal of the Institute of Convergence Signal Processing
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    • v.10 no.2
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    • pp.132-135
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    • 2009
  • The video similarity measure is very important factor to index and to retrieve for video data. In this paper, we propose the luminance projection model to measure the video similarity efficiently. Most algorithms for video indexing have been commonly used histograms, edges, or motion features, whereas in this paper, the proposed algorithm is employed an efficient measure using the luminance projection. To index effectively the video sequences and to decrease the computational complexity, we calculate video similarity using the key frames extracted by the cumulative measure, and compare the set of key frames using the modified Hausdorff distance. Experimental results show that the proposed luminance projection model yields the remarkable accuracy and performance than the conventional algorithm.

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Inactive Regions Padding Methods for Rotated Sphere Projection of 360 Video

  • Yoon, Yong-Uk;Kim, Hyun-Ho;Kim, Jae-Gon
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2018.06a
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    • pp.200-201
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    • 2018
  • In the workflow of 360 video coding of JVET (Joint Video Experts Team), firstly the 360 videos are projected onto the 2D plane with diverse projection formats, such as Equi-Rectangular Projection (ERP), Cubemap Projection (CMP), Rotated Sphere Projection (RSP), etc. The projection format of RSP has inactive regions in the converted 2D plane. The inactive regions may cause visual artifact as well as the reduction of the coding efficiency due to discontinuity at boundaries between active and inactive regions. In this paper, to overcome these problems, the inactive regions are padded by using two types of adjacent pixels. Then padded regions of RSP are blended with inactive regions padded by proposed method. The experimental results demonstrate that, in terms of end-to-end WS-PSNR-NN, the proposed method achieves 0.1% BD-rate reduction. In addition, the visual artifacts along the borders between discontinuous faces are noticeably reduced.

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A Study on Projection Conversion for Efficient 3DoF+ 360-Degree Video Streaming

  • Jeong, Jong-Beom;Lee, Soonbin;Jang, Dongmin;Kim, Sungbin;Lee, Sangsoon;Ryu, Eun-Seok
    • Journal of Broadcast Engineering
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    • v.24 no.7
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    • pp.1209-1220
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    • 2019
  • The demand for virtual reality (VR) is rapidly increasing. Providing the immersive experience requires much operation and many data to transmit. For example, a 360-degree video (360 video) with at least 4K resolution is needed to offer an immersive experience to users. Moreover, the MPEG-I group defined three degrees of freedom plus (3DoF+), and it requires the transmission of multiview 360 videos simultaneoulsy. This could be a burden for the VR streaming system. Accordingly, in this work, a bitrate-saving method using projection conversion is introduced, along with experimental results for streaming 3DoF+ 360 video. The results show that projection conversion of 360 video with 360lib shows a Bjontegaard delta bitrate gain of as much as 11.4%.

Efficient Video Retrieval Scheme with Luminance Projection Model (휘도투시모델을 적용한 효율적인 비디오 검색기법)

  • Kim, Sang Hyun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.16 no.12
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    • pp.8649-8653
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    • 2015
  • A number of video indexing and retrieval algorithms have been proposed to manage large video databases efficiently. The video similarity measure is one of most important technical factor for video content management system. In this paper, we propose the luminance characteristics model to measure the video similarity efficiently. Most algorithms for video indexing have been commonly used histograms, edges, or motion features, whereas in this paper, the proposed algorithm is employed an efficient similarity measure using the luminance projection. To index the video sequences effectively and to reduce the computational complexity, we calculate video similarity using the key frames extracted by the cumulative measure, and compare the set of key frames using the modified Hausdorff distance. Experimental results show that the proposed luminance projection model yields the remarkable improved accuracy and performance than the conventional algorithm such as the histogram comparison method, with the low computational complexity.

Geometry Padding for Segmented Sphere Projection (SSP) in 360 Video (360 비디오의 SSP를 위한 기하학적 패딩)

  • Kim, Hyun-Ho;Myeong, Sang-Jin;Yoon, Yong-Uk;Kim, Jae-Gon
    • Journal of Broadcast Engineering
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    • v.24 no.1
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    • pp.25-31
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    • 2019
  • 360 video is attracting attention as immersive media, and is also considered in VVC (Versatile Video Coding), which is being developed in JVET (Joint Video Expert Team) as a new video coding standard of post-HEVC. A 2D image projected from 360 video for its compression may has discontinuities between the projected faces and inactive regions, and they may cause the visual artifacts in the reconstructed video as well as decrease of coding efficiency. In this paper, we propose a method of efficient geometric padding to reduce these discontinuities and inactive regions in the projection format of SSP (Segmented Sphere Projection). Experimental results show that the proposed method improves subjective quality compared to the existing padding of SSP that uses copy padding with minor loss of coding gain.

Digital Video Warping for Convergence of Projection TV Receivers (프로젝션 TV에서의 광학적 왜곡 보정 알고리즘)

  • Hwang, Kyu-Young;Shin, Hyun-Chool;Woong Seo;Song, Woo-Jin
    • Proceedings of the IEEK Conference
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    • 2001.09a
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    • pp.535-538
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    • 2001
  • In this paper, we present a novel method to solve the inevitable RGB beam mismatch problem in projection TV receivers. Conventional methods solve the mismatch problem by directly controlling the cathode ray tube (CRT) using the convergence yoke (CY). Unlike conventional methods, the proposed method is based on digital video processing using image warping techniques. Firstly RGB beam projection paths are mathematically modeled. Then based on the modeling, the input video signal to CRT is prewarped so that RGB beams are landed at the same point on the screen. Since the proposed method is based on a digital video processing instead of using CY, it can outperform the conventional method in terms of quality and cost. The experimental results with a real 60´projection TV demonstrate that the proposed method indeed produces converged images on the projection TV screen.

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An Identification Method of Detrimental Video Images Using Color Space Features (컬러공간 특성을 이용한 유해 동영상 식별방법에 관한 연구)

  • Kim, Soung-Gyun;Kim, Chang-Geun;Jeong, Dae-Yul
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.12 no.6
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    • pp.2807-2814
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    • 2011
  • This paper proposes an identification algorithm that detects detrimental digital video contents based on the color space features. In this paper, discrimination algorithm based on a 2-Dimensional Projection Maps is suggested to find targeted video images. First, 2-Dimensional Projection Maps which is extracting the color characteristics of the video images is applied to extract effectively detrimental candidate frames from the videos, and next estimates similarity between the extracted frames and normative images using the suggested algorithm. Then the detrimental candidate frames are selected from the result of similarity evaluation test which uses critical value. In our experimental test, it is suggested that the results of the comparison between the Color Histogram and the 2-Dimensional Projection Maps technique to detect detrimental candidate frames. Through the various experimental data to test the suggested method and the similarity algorithm, detecting method based on the 2-Dimensional Projection Maps show more superior performance than using the Color Histogram technique in calculation speed and identification abilities searching target video images.

Video Art and Media Environment in City Space (도시 공간에서의 비디오 아트와 미디어 환경에의 재고)

  • Sohn, Young-Sil
    • The Journal of the Korea Contents Association
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    • v.11 no.4
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    • pp.196-206
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    • 2011
  • The development of projection technology produces series of discussions associated to various form of visual immersing possibilities by the way of projecting image directly to the obscure surface surrounded us. Besides, the significance can be found in terms of that this kind of image projection offers chance to citizens to enjoy high standard images and makes people consider media environment of city. Video art as the digital technology grafts penetrates formative space of city by projecting images. The certain thing about questions how the media has status in city is that media is now not existing for self neither for abstractly and virtual reality is existing in the general appearance of metropolis. This paper treats media environment of city and the meaning of image projection as from of video art in the city. It accesses about the meaning of video form visual art in big city- new reality, the virtual and the real, immersion and interactivity. And media reality of metropolis defines that there is not one major discourse in the gigantic text -metropolis rather they are different discourses each other simultaneously compatible in the gigantic text -metropolis and in fact, they affect each other and interact.