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7th IEEE International Symposium on Signal Processing and Information Technology

作者： Bagheri, M. Lotfi, T. Darabi, A. A. Kasaei, S. Sharif Univ Technol Image Proc Lab Dept Comp Engn Tehran Iran

ISBN: (纸本)9781424418343

This paper presents a novel video encoding method for cooperative Educational Dissemination Systems. Taking into consideration the inherent characteristics of distance learning video streams, existing a few moving objects in the scene and objects having slow motions, we propose a novel content-based video encoding method which is very efficient on low bandwidth channels. In the encoding process, we apply a background subtraction algorithm for motion segmentation with a novel statistical background modeling. In each frame, the moving objects are extrapolated with rectangular bounding boxes which are the only data send over the low bandwidth channel. In the decoding process, we propose a new scene modeling algorithm based on video mosaicing, to reconstruct the original video scene from the partially overlapped frames. Our conducted experiments show that the proposed encoding and decoding algorithms are very efficient in real-time video webcasting with maximum 18 fps for CIF formatted sequences and produce 8 to 12 percent bitrate saving when compared to the H.264 standard.

关键词： content-based video coding distance learning motion segmentation mosaicing H.264

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content-based video coding of newscasts for mobile devices

Content-based video coding of newscasts for mobile devices

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International Conference on Imaging Science, Systems, and Technology - Computer Graphics

作者： Geisler, S Tech Univ Clausthal Dept Comp Sci Clausthal Zellerfeld Germany

ISBN: (纸本)1932415645

The transmission of video content for mobile devices requires video codecs for low bit rates. In this paper content-based video coding is used to approximately half the required bandwidth for news speaker scenes without additional loss of quality. A second aspect is the problem, of the small display sizes, which leads to the loss of details. content-based video coding can be used to allow a more detailed look at different video objects. Both advantages can be achieved, by using seperate video streams for the different objects of the scene. The necessary segmentation for newscaster scenes is also provided.

关键词： content-based video coding region of interest mobile devices

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Segmentation and tracking of moving objects for content-based video coding

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IEE PROCEEDINGS-VISION IMAGE AND SIGNAL PROCESSING 1999年第3期146卷 144-150页

作者： Meier, T Ngan, KN Univ Western Australia Dept Elect & Elect Engn Visual Commun Res Grp Perth WA 6907 Australia

To enable content-based functionalities in video coding, a decomposition of the scene into physical objects is required. Such objects are normally not characterised by homogeneous colour, intensity, or optical flow Therefore, conventional techniques based on these low-level features cannot perform the desired segmentation. The authors address segmentation and tracking of moving objects and present a new video object plane (VOP) segmentation algorithm that extracts semantically meaningful objects. A morphological motion filter detects physical objects by identifying areas that are moving differently from the background. A new filter criterion is introduced that measures the deviation of the estimated local motion from the synthesised global motion. A two-dimensional binary model is derived for the object of interest and tracked throughout the sequence by a Hausdorff object tracker. To accommodate for rotations and changes in shape, the model is updated every frame by a two-stage method that accounts for rigid and non-rigid moving parts of the object. The binary model then guides the actual VOP extraction, whereby a novel boundary post-processor ensures high boundary accuracy. Experimental results demonstrate the performance of the proposed algorithm.

关键词： image sequence moving objects segmentation video coding motion estimation high boundary accuracy rigid moving parts scene decomposition feature extraction image segmentation Hausdorff object tracker Filtering methods in signal processing content-based video coding video signal processing moving objects tracking two-dimensional binary model edge detection filter criterion morphological motion filter local motion estimation boundary post-processor performance Image recognition tracking Image and video coding nonrigid moving parts filtering theory synthesised global motion image sequences video object plane VOP segmentation algorithm experimental results

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A content-based video coding approach for rigid and non-rigid textures

A content-based video coding approach for rigid and non-rigi...

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IEEE International Conference on Image Processing (ICIP 2006)

作者： Ndjiki-Nya, Patrick Hinz, Tobias Stuber, Christoph Wiegand, Thomas Fraunhofer Heinrich Hertz Inst Image Proc Dept Berlin Germany

ISBN: (纸本)9781424404810

A generic, content-based video coding framework is described. The approach is based on H.264/MPEG4-AVC that is extended by a closed-loop texture analysis / synthesis algorithm. The texture analysis yields regions that can be reproduced with reduced accuracy at the decoder without noticeable quality degradations. These textures are synthesized at the decoder given side information generated through analysis. The remainder regions are coded using H.264/MPEG4-AVC that serves as fallback option in our framework. Texture synthesis is constrained in the proposed system as the area to synthesize is typically surrounded by one or more textures. In this paper, it is shown that constrained synthesis can be done successfully for a large class of textures including non-rigid textures such as water. Experimental results verify improvements of the proposed system compared to H.264/MPEG4-AVC without our approach.

关键词： content-based video coding texture analysis texture synthesis H.264/MPE4-AVC

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An Efficient content-based video coding Method for Distance Learning Applications

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SCIENTIA IRANICA TRANSACTION D-COMPUTER SCIENCE & ENGINEERING AND ELECTRICAL ENGINEERING 2009年第2期16卷 85-103页

作者： Lotfi, T. Bagheri, M. Darabi, A. A. Kasaei, S. Sharif Univ Technol Dept Comp Engn Tehran Iran

This paper presents a novel method for cooperative educational dissemination systems. Taking into consideration the inherent characteristics of distance learning video streams (existence of a few slow moving objects in a classroom), we have proposed a novel content-based video coding method that is very efficient at low bitrate channels. On the encoding side, we have applied a background subtraction algorithm for motion segmentation using a novel statistical background modeling approach. At each frame, the moving objects are extrapolated with a rectangular model and tracked frame by frame (which forms the only data needed to be sent over the channel). On the decoding side, we have used a new error concealment algorithm (based on edge information of frames) to eliminate probable channel errors in, the received data. Moreover, a new fuzzy scene modeling algorithm. is proposed that adaptively computes the alpha blending coefficient (used in. dynamic video mosaicing) and reconstructs the original video scene from partially overlapped frames. Our experiments show that the proposed coding system is very efficient in real-time video webcasting with approximately 24 fps for CIF formatted sequences (and at a minimum of 13 fps transmission for 720 x 576 frame sizes). Applying our proposed system. has reduced the required bitrate of H.264 and MPEG-4 coding standards by about 2.5% to 8%, respectively, with almost the same, or even better, reconstructed video qualities.

关键词： content-based video coding Distance learning Motion segmentation Mosaicing

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content-based 3-D Mosaics for Representing videos of Dynamic Urban Scenes

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR video TECHNOLOGY 2012年第2期22卷 295-308页

作者： Tang, Hao Zhu, Zhigang CUNY Grad Ctr Dept Comp Sci New York NY 10016 USA CUNY City Coll Dept Comp Sci New York NY 10031 USA

We propose a content-based 3-D mosaic (CB3M) representation for long video sequences of 3-D and dynamic urban scenes captured by a camera on a mobile platform. In the first phase, a set of parallel-perspective (pushbroom) mosaics with varying viewing directions is generated to capture both the 3-D and dynamic aspects of the scene under the camera coverage. In the second phase, a segmentation-based stereo matching algorithm is applied to extract parametric representations of the color, structure and motion of the dynamic and/or 3-D objects in urban scenes, where a lot of planar surfaces exist. Multiple pairs of stereo mosaics are used for facilitating reliable stereo matching, occlusion handling, accurate 3-D reconstruction, and robust moving target detection. CB3M is a highly compressed visual representation for a dynamic 3-D scene, and has object contents of both 3-D and motion information. Experimental results are given for various real video sequences of large-scale 3-D scenes.

关键词： 3-D scene representation content-based video coding image-based modeling multi-image registration

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Joint source-channel multistream coding and optical network adapter design for video over IP

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IEEE TRANSACTIONS ON MULTIMEDIA 2002年第1期4卷 3-22页

作者： Chen, J Liu, KJR Univ Maryland Dept Elect & Comp Engn Syst Res Inst College Pk MD 20742 USA

In this paper, we present a panorama picture on how to achieve end-to-end video over IP services under the communication environments, consisting of backbone networks, hybrid access networks, and the end users. The paper consists of three equally weighted subtopics which cover some novel thoughts in designing and implementing the video over IP system in the different areas, namely, a Synchronous Optical NETwork (SONET) network adapter for backbone connections, the joint source-channel multistream coding in hybrid access networks, and the content-based source coding in the transform domain. We propose to link the three different problems associated with the hybrid networks, which have different characteristics and design requirements, to improve the critical performances in various areas of video over IP systems. The goal is to deliver video over IP networks in more cost-effective and reliable manner. IP/ATM over SONET is currently a commonly used backbone technique. In the first part of this paper, we present a flexible design and implementation of a SONET network adapter to carry IP traffic via optical fiber. Unlike many conventional designs, our single-chip implementation supports different data rates (OC-3, OC-12, and OC-48), carries IP traffic directly over fiber, achieves more flexible for multivendor interoperability, and provides bandwidth efficient designs at the lower system latency. Hybrid access-networks via wireline or wireless connections are most likely needed for last-mile services. In the second part of this paper, we propose a joint source-channel multfstream video coding scheme to combat the transmission errors under the harsh network conditions. On top of traditional error control techniques, the simulation results demonstrate that our multistream design outperform the conventional approaches by up to 5-7 dB under the harsh network conditions. To support our multistream video coding scheme, we need to access and manipulate video objects rather tha

关键词： content-based video coding error-resilient transmission joint source-channel coding optical network SONET streaming video video over IP

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content-based 3D mosaic representation for video of dynamic 3D scenes 34

Content-based 3D mosaic representation for video of dynamic ...

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34th Applied Imagery and Pattern Recognition Workshop (AIPR 2005)

作者： Zhu, Zhigang Tang, Hao Wolberg, George Layne, Jeffery R. CUNY City Coll Dept Comp Sci New York NY 10031 USA US Air Force Res Lab Wright Patterson AFB OH 45433 USA

ISBN: (纸本)0769524796

We propose a content-based three-dimensional (3D) mosaic representation for long video sequences of 3D and dynamic scenes captured by a camera on a mobile platform. The motion of the camera has a dominant direction of motion (as on an airplane or ground vehicle), but 6 degrees-of-freedom (DOF) motion is allowed. In the first step, a pair of generalized parallel-perspective (pushbroom) stereo mosaics is generated that captured both the 3D and dynamic aspects of the scene under the camera coverage. In the second step, a segmentation-based stereo matching algorithm is applied to extract parametric representation of the color, structure and motion of the dynamic and/or 3D objects in urban scenes where a lot of planar surfaces exist. based on these results, the content-based 3D mosaic (CB3M) representation is created, which is a highly compressed visual representation for very long video sequences of dynamic 3D scenes. Experimental results will be given.

关键词： image fusion multi-image registration video surveillance content-based video coding

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Local Texture Synthesis: A Static Texture coding Algorithm Fully Compatible With HEVC 22

Local Texture Synthesis: A Static Texture Coding Algorithm F...

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22nd International Conference on Systems, Signals and Image Processing (IWSSIP)

作者： Naser, Karam Ricordel, Vincent Le Callet, Patrick Univ Nantes LUNAM Univ CNRS UMR 6597IRCCyNPolytech Nantes Rue Christian PaucBP 50609 F-44306 Nantes 3 France

ISBN: (纸本)9781467383530

Textures are one of the main characteristics of the visual scene. Perceptually, their details are less important than their semantic meaning. This property has been exploited in many texture coding (content based video coding) approaches by removing parts of the textures in the encoder and synthesizing them at the decoder side. Such an approach would necessarily need modification of the coding process and violating the standard. This paper introduces a novel algorithm for texture coding called Local Texture Synthesis (LTS), in which texture synthesis is employed in a full compatibility with HEVC standard. This implies that a basic HEVC decoder can be used to reconstruct the signal. LTS defines the necessary conditions to synthesize a patch and produces different synthesis of it. It tries then coding each of them, and finally chooses the one that minimizes the coding cost. A prototype of this algorithm, based on Markov Random Fields, is given in this paper. This prototype provides up to 10% bitrate saving (using the same quantization parameter) while maintaining an equivalent visual quality.

关键词： Texture coding Perceptual Optimization content-based video coding Beyond HEVC

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content-based rate control for low bit-rate video applications

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Conference on Visual Communications and Image Processing

作者： Shi, KW Cai, A Sun, JG Beijing Univ Posts & Telecommun Beijing 100876 Peoples R China

ISBN: (纸本)0819437034

In low bit-rate or very low bit-rate video applications, such as videophone and video conferencing, it is difficult for traditional methods to gain a satisfactory image quality. They often suffer from some shortcomings: images with artifacts caused by limited bandwidth and motion discontinuity caused by frame skipping when bit-streams are transmitted through a fixed rate channel in low-delay applications. To attack the two problems above, we propose a content-based rate control method for videophone and video conferencing applications. Our work is focused on three aspects: analysis of bit-streams in low bit-rate video applications, content-based bit allocation to facial areas and background, and low-delay rate control in object-layer. Experiments show that the proposed method can achieve better subjective quality compared with that of the test model TMN5 of H.263, and slightly worse performance in PSNR, but with significantly better subjective quality in the facial areas, compared with that of the TMN8 of H.263+.

关键词： rate control low bit-rate video coding bit allocation content-based video coding

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