检索结果-内蒙古大学图书馆

region-based image coding with multiple algorithms

IEEE TRANSACTIONS ON GEOSCIENCE AND REMOTE SENSING 2001年第3期39卷 562-570页

作者： Petrou, M Hou, PX Kamata, S Underwood, CI Univ Surrey Sch Elect Comp & Math Guildford GU2 7XH Surrey England Kyushu Univ Grad Sch Informat Sci & Elect Engn Dept Intelligent Syst Fukuoka 81281 Japan

The wide usage of small satellite imagery, especially its commercialization, makes data-based onboard compression not only meaningful but also necessary in order to solve the bottleneck between the huge volume of data generated onboard and the very limited downlink bandwidth. In this paper, we propose a method that encodes different regions with different algorithms. We use three shape-adaptive image compression algorithms as the candidates. The first one is a JPEG-based algorithm, the second one is based on the object-based wavelet transform (OWT) method proposed by [1], and the third adopts Hilbert scanning of the regions of interest followed by one-dimensional (1-D) wavelet transform. The three algorithms are also applied to the full image so that we can compare their performance on a whole rectangular image. We use eight Landsat Th I multispectral images and another 12 small satellite single-band images as our data set. The results show that these compression algorithms have significantly different performance for different regions. For relatively smooth regions, e.g., regions that consist of a single type of vegetation or water areas etc, the 1-D wavelet method is the best. For highly textured regions, e.g., urban areas, mountain areas, and so on, the modified OWT method wins over the others. For the whole image, OWT working at whole image mode, which is just an ordinary 2-D wavelet compression, is the heat. based on this, we propose a new data-based compression architecture that extracts particular regions according to the application of interest and then involves different algorithms to encode different regions in order to achieve better performance than traditional onboard compression schemes in which a fixed compression method is applied to the whole image no matter what the application is. This approach is most appropriate for use with images captured by microsatellites, which are commissioned for specific applications in which one knows a priori which cla

关键词： adaptive coding image coding region-based coding remote sensing

来源：评论

学校读者我要写书评

暂无评论

Costs and advantages of shape-adaptive wavelet transform for region-based image coding

Costs and advantages of shape-adaptive wavelet transform for...

引用

IEEE International Conference on Image Processing (ICIP 2005)

作者： Cagnazzo, M Poggi, G Verdoliva, L Univ Naples Federico II Dipartimento Ingn Elettron & Telecomun I-80125 Naples Italy

ISBN: (纸本)0780391349

region-based encoding techniques have been long investigated for the compression of still images and video sequences and have recently gained much popularity, as testified by the object-based nature of the MPEG-4 video coding standard. This work aims at analyzing costs and advantages of implementing such an approach by shape-adaptive wavelet transform and shape-adaptive SPIHT. The analysis of several performance measures in a number of experiments confirm the potential of wavelet-based region-based approach, and provide insight about what performance gains and losses can be expected in various operative conditions.

关键词： image coding region-based coding shape-adaptive wavelet transform

来源：评论

学校读者我要写书评

暂无评论

Fractal video sequences coding with region-based functionality

引用

APPLIED MATHEMATICAL MODELLING 2012年第11期36卷 5633-5641页

作者： Zhu, Shiping Hou, Yangshuan Wang, Zaikuo Belloulata, Kamel Beihang Univ Dept Measurement Control & Informat Technol Sch Instrumentat Sci & Optoelect Engn Beijing 100191 Peoples R China Chinese Acad Sci Key Lab Technol Geospatial Informat Proc & Applic Inst Elect Beijing 100190 Peoples R China Univ Djilali Liabes Sidi Bel Abbes Dept Elect Fac Sci Ingn Sidi Bel Abbes 22000 Algeria

In this paper, we explore the fractal video sequences coding in the context of region-based functionality. Since the main drawback of fractal coding is the high computational complexity, some schemes are proposed to speed up the encoding process. As fractal encoding essentially spends most time on the search for the best-matching block in a large domain pool, this paper firstly ameliorates the conventional CPM/NCIM method and then applies a new hexagon block-matching motion estimation technology into the fractal video coding. The images in the video sequences are encoded region by region according to a previously-computed segmentation map. Experimental results indicate that the proposed algorithm spends less encoding time and achieves higher compression ratio and compression quality compared with the conventional CPM/NCIM method. (C) 2012 Elsevier Inc. All rights reserved.

关键词： Fractal video coding region-based coding Motion estimation H.264

来源：评论

学校读者我要写书评

暂无评论

region-based H.263+ coding for real-time video communication

Region-based H.263+ coding for real-time video communication

引用

Conference on Visual Communications and Image Processing 2002

作者： Chiew, TK Chung-How, JTH Bull, DR Canagarajah, CN Univ Bristol Commun Res Ctr Image Commun Grp Bristol BS8 1TH Avon England

ISBN: (纸本)0819444111

This paper proposes a novel low-complexity region-based video-coding algorithm that automatically identifies moving foreground objects, compresses them with higher quality than the background and efficiently encodes the video in an H.263+ compliant bitstream. Global motion estimation is first performed using the MSE algorithm. The original sequence is then segmented into foreground and background regions by using global and local motion information predicted from the previous frame. This enables the separation of moving objects with respect to a static background, even in the presence of camera motion. A modified TMN8 rate control algorithm is proposed to assign more bits to the foreground region, and the segmented video is then encoded into an H.263+ compliant bitstream. As block-matching motion estimation is used to obtain the local motion field and foreground/background identification is also block-based, the proposed algorithm has lower complexity than previously proposed pixel-based algorithms. Hence it is can be easily implemented in software or ASIC-based real-time applications. It is also particularly useful for mobile applications where bandwidth is highly constrained and low power requirements restrict processing complexity.

关键词： region-based coding foreground/background segmentation global motion H.263+

来源：评论

学校读者我要写书评

暂无评论

region-based fractal video coding

Region-based fractal video coding

引用

7th International Symposium on Instrumentation and Control Technology

作者： Zhu, Shiping Belloulata, Kamel Beihang Univ Dept Measurement Control & Informat Technol Sch Instrumentat Sci & Optoelect Engn Beijing 100083 Peoples R China Univ Djilali Liabes Sidi Bel Abbes Fac Sci Ingn Dept Elect Sidi Bel Abbes 22000 Algeria

ISBN: (纸本)9780819473622

A novel video sequence compression scheme is proposed in order to realize the efficient and economical transmission of video sequence, and also the region-based functionality of MPEG-4. The CPM and NCIM fractal coding scheme is applied on each region independently by a prior image segmentation map (alpha plane) which is exactly the same as defined in MPEG-4. The first n frames of video sequence are encoded as a "set" using the Circular Prediction Mapping (CPM) and encode the remaining frames using the Non Contractive Interframe Mapping (NCIM). The CPM and NCIM accomplish the motion estimation and compensation, which can exploit the high temporal correlations between the adjacent frames of video sequence. The experimental results with the monocular video sequences provide promising performances at low bit rate coding, such as the application in video conference. We believe the proposed fractal video codec will be a powerful and efficient technique for the region-based video sequence coding.

关键词： Monocular video coding fractal coding region-based coding low bit rate coding

来源：评论

学校读者我要写书评

暂无评论

Adaptive approximation bounds for vertex based contour encoding

引用

IEEE TRANSACTIONS ON IMAGE PROCESSING 1999年第8期8卷 1142-1147页

作者： Kim, KJ Lim, CW Kang, MG Park, KT Hyundai Elect Ind Co Seoul 130070 South Korea Daewoo Elect Co Seoul 100714 South Korea Yonsei Univ Dept Elect Engn Seoul 120749 South Korea

When approximating the shape of a region, a fixed bound on the tolerable distortion is set for approximating its contour points. In this work, an adaptive approximation bound for lossy coding of the contour points is proposed. A function representing the relative significance of the contour points is defined to adjust the distortion bound along the region contour allowing an adaptive approximation of the region shape. The effectiveness of the adaptive contour coding approach for a region-based coding system is verified through experiments.

关键词： contour approximation region-based coding vertex coding

来源：评论

学校读者我要写书评

暂无评论

ROI-based DICOM image compression for telemedicine

引用

SADHANA-ACADEMY PROCEEDINGS IN ENGINEERING SCIENCES 2013年第1期38卷 123-131页

作者： Bairagi, Vinayak K. Sapkal, Ashok M. Sinhgad Acad Engn Dept Elect Engn Pune 411048 Maharashtra India Coll Engn Dept Elect Engn Pune 411005 Maharashtra India

Many classes of images contain spatial regions which are more important than other regions. Compression methods capable of delivering higher reconstruction quality for important parts are attractive in this situation. For medical images, only a small portion of the image might be diagnostically useful, but the cost of a wrong interpretation is high. Hence, region based coding (RBC) technique is significant for medical image compression and transmission. Loss less compression schemes with secure transmission play a key role in telemedicine applications that help in accurate diagnosis and research. In this paper, we propose lossless scalable RBC for Digital Imaging and Communications in Medicine (DICOM) images based on Integer Wavelet Transform (IWT) and with distortion limiting compression technique for other regions in image. The main objective of this work is to reject the noisy background and reconstruct the image portions losslessly. The compressed image can be accessed and sent over telemedicine network using personal digital assistance (PDA) like mobile.

关键词： DICOM image integer wavelet transform lossless compression medical image compression region-based coding telemedicine

来源：评论

学校读者我要写书评

暂无评论

Low-complexity compression of multispectral images based on classified transform coding

引用

SIGNAL PROCESSING-IMAGE COMMUNICATION 2006年第10期21卷 850-861页

作者： Cagnazzo, Marco Cicala, Luca Poggi, Giovanni Verdoliva, Luisa Univ Naples Federico II Dipartimento Ingn Elettron & Telecomunicaz Naples Italy

Compression of remote-sensing images can be necessary in various stages of the image life, and especially on-board a satellite before transmission to the ground station. Although on-board CPU power is quite limited, it is now possible to implement sophisticated real-time compression techniques, provided that complexity constraints are taken into account at design time. In this paper we consider the class-based multispectral image coder originally proposed in [Gelli and Poggi, Compression of multispectral images by spectral classification and transform coding, IEEE Trans. Image Process. (April 1999) 476-489 [5]] and modify it to allow its use in real time with limited hardware resources. Experiments carried out on several multispectral images show that the resulting unsupervised coder has a fully acceptable complexity, and a rate-distortion performance which is superior to that of the original supervised coder, and comparable to that of the best coders known in the literature. (C) 2006 Elsevier B.V. All rights reserved.

关键词： multispectral images remote sensing image compression region-based coding low complexity

来源：评论

学校读者我要写书评

暂无评论

A new class of fast shape-adaptive orthogonal transforms and their application to region-based image compression

引用

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 1999年第1期9卷 16-34页

作者： Stasinski, R Konrad, J INRS Telcommun Verdun PQ H3E 1H6 Canada

region-based approaches to image and video compression have been very actively explored in the last few years. It is widely expected that they will result in rate/quality gains and expanded functionalities. In such approaches, one of the essential problems is the representation of luminance and color in arbitrarily shaped regions. For rectangular blocks extracted from natural images, the discrete cosine transform (DCT) has been found to perform close to the eigentransform, Although for arbitrarily shaped regions orthoganalization-based procedures have been shown to perform very well, their computational complexity and memory requirements are prohibitive for today's technology, Therefore, other approaches are presently investigated, and particular attention is paid to low implementation complexity. In this paper, me propose a new class of orthogonal transforms that self-adapt to arbitrary shapes. The new algorithms are derived from flow graphs of standard fast transform algorithms by a suitable modification of certain butterfly operators. First, we show how to derive a shape-adaptive transform from the discrete Walsh-Hadamard transform (DWHT) how graph. Then, we discuss modifications needed to arrive at a DCT-based shape-adaptive transform. We give implementation details of this transform, and compare its computational complexity with several well-known approaches. We also evaluate the energy compaction performance of the new transform for both synthetic and natural data. We conclude that the proposed DCT-based shape-adaptive transform gives a very beneficial compaction/complexity ratio compared to other well-known approaches. The complexity of the new method does not exceed the complexity of two nonadaptive DCT's on a circumscribing rectangle, and therefore, unlike other tested methods with comparable energy compaction, it is suitable for large regions, This property should prove very valuable in the future when true region-based image/video compression methods are

关键词： discrete cosine transform (DCT) MPEG-4 region-based coding SA-DCT shape-adaptive transforms transform coding

来源：评论

学校读者我要写书评

暂无评论

Segmentation-based video coding system allowing the manipulation of objects

引用

IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS FOR VIDEO TECHNOLOGY 1997年第1期7卷 60-74页

作者： Salembier, P Marques, F Pardas, M Morros, JR Corset, I Jeannin, S Bouchard, L Meyer, F Marcotegui, B PHILIPS RES LABS F-94453 LIMEIL BREVANNES FRANCE PARIS SCH MINES F-77305 FONTAINEBLEAU FRANCE

This paper presents a generic video coding algorithm allowing the content-based manipulation of objects. This manipulation is possible thanks to the definition of a spatiotemporal segmentation of the sequences. The coding strategy relies on a joint optimization in the rate-distortion sense of the partition definition and of the coding techniques to be used within each region. This optimization creates the link between the analysis and synthesis parts of the coder. The analysis defines the time evolution of the partition, as well as the elimination or the appearance of regions that are homogeneous either spatially or in motion. The coding of the texture as well as of the partition relies on region-based motion compensation techniques, The algorithm offers a good compromise between the ability to track and manipulate objects and the coding efficiency.

关键词： affine motion estimation compensation rate-distortion optimization region-based coding spatiotemporal segmentation video coding

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：