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Call for Papers - use pdf supplied 论文征集-使用pdf提供

Real-Time Imaging Pub Date : 2004-12-01 DOI: 10.1016/S1077-2014(04)00097-X

引用次数: 0

A wavelet subspace method for real-time face tracking 一种小波子空间实时人脸跟踪方法

Real-Time Imaging Pub Date : 2004-12-01 DOI: 10.1016/j.rti.2004.06.002

Rogerio S. Feris , Volker Krueger , Roberto M. Cesar Jr.

引用次数: 25

RVLC decoding scheme for improved data recovery in MPEG-4 video coding standard 改进MPEG-4视频编码标准中数据恢复的RVLC解码方案

Real-Time Imaging Pub Date : 2004-10-01 DOI: 10.1016/j.rti.2004.07.003

Sunil Kumar, Liyang Xu

{"title":"RVLC decoding scheme for improved data recovery in MPEG-4 video coding standard","authors":"Sunil Kumar, Liyang Xu","doi":"10.1016/j.rti.2004.07.003","DOIUrl":"10.1016/j.rti.2004.07.003","url":null,"abstract":"<div><p><span>In this paper, we present a low-complexity ‘reversible variable length code’ (RVLC) decoding scheme for MPEG-4 video that recovers more blocks and sometimes more macroblocks (MBs) from error propagation region of corrupted video packets, as compared to the MPEG-4 scheme. The remaining blocks and MBs are concealed. Simulation studies have been carried out to show that the proposed scheme achieves better data recovery, both in terms of peak-signal-to-noise ratio (PSNR) and </span>perceptual quality<span>. In addition, we present more conditions for error detection than those suggested in MPEG-4, discuss properties of error propagation in corrupted video packets, and provide the RVLC codeword structure. The use of RVLC code structure will enable the decoding in both directions by using only one code table, instead of separate tables used for forward and backward decoding. Since the scheme is purely decoder based, the compliance with the standard is fully maintained. It is very simple for the decoder to keep track of the additional blocks/MBs recovered by the proposed scheme. Therefore, the data recovery scheme suggested in MPEG-4 can still be used as default scheme.</span></p></div>","PeriodicalId":101062,"journal":{"name":"Real-Time Imaging","volume":"10 5","pages":"Pages 315-323"},"PeriodicalIF":0.0,"publicationDate":"2004-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.rti.2004.07.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74179905","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 6

An effective motion vector re-estimation method for low bit-rate video transcoding 一种有效的低比特率视频转码运动矢量重估计方法

Real-Time Imaging Pub Date : 2004-10-01 DOI: 10.1016/j.rti.2004.08.004

June-Sok Lee, Goo-Rak Kwon, Jae-Won Kim, Nam-Hyeong Kim, Sung-Jea Ko

引用次数: 2

Low bit-rate multimedia communication 低比特率多媒体通信

Real-Time Imaging Pub Date : 2004-10-01 DOI: 10.1016/j.rti.2004.09.001

Shan Suthaharan , Mrinal Mandal (Guest Editors)

引用次数: 0

Real-time scheduling based on imprecise computation for scalable streaming media system over the Internet 基于不精确计算的可扩展流媒体系统实时调度

Real-Time Imaging Pub Date : 2004-10-01 DOI: 10.1016/j.rti.2004.08.002

Kui Gao , Wen Gao , Simin He , Yuan Zhang

引用次数: 4

A novel DCT domain transcoder for transcoding video streams with half-pixel motion vectors 一种用于半像素运动向量视频流转码的新型DCT域转码器

Real-Time Imaging Pub Date : 2004-10-01 DOI: 10.1016/j.rti.2004.07.002

Gang Cao , Zhijun Lei , Jintao Li , Nicolas D. Georganas , Zhenmin Zhu

{"title":"A novel DCT domain transcoder for transcoding video streams with half-pixel motion vectors","authors":"Gang Cao , Zhijun Lei , Jintao Li , Nicolas D. Georganas , Zhenmin Zhu","doi":"10.1016/j.rti.2004.07.002","DOIUrl":"10.1016/j.rti.2004.07.002","url":null,"abstract":"<div><p><span>Video transcoding<span> is one of the key techniques to provide heterogeneous multimedia applications with </span></span><em>Universal Multimedia Access</em> (UMA) service. Recently, compressed domain (DCT, Discrete Cosine Transform) transcoding architectures have been proposed to achieve fast transcoding, in which DCT domain <em>Inverse Motion Compensation</em><span><span> (IMC) is the most important module to reduce computational complexity. The problem of IMC has been studied for integer-pixel precision motion vectors (MVs), and, subsequently, for half-pixel precision MVs in which extra filtering, hence, extra computation is introduced. Since most current video coding standards, such as H.263, MPEG-2, etc., use half-pixel precision MVs to achieve better quality, reducing computational complexity of IMC for half-pixel MVs is important for real time fast transcoding video streams encoded by these standards. In this paper, we propose a novel half-pixel filter for IMC, which simplifies the extract operations by integrating the interpolation and translation operations into one single step. Compared to other existing half-pixel </span>filtering algorithms<span>, the proposed filter does not introduce any distortion and drift errors. Experimental results demonstrate that the proposed filter achieves faster transcoding than other DCT domain transcoders, and almost the same video quality as that of pixel domain transcoders.</span></span></p></div>","PeriodicalId":101062,"journal":{"name":"Real-Time Imaging","volume":"10 5","pages":"Pages 331-337"},"PeriodicalIF":0.0,"publicationDate":"2004-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.rti.2004.07.002","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"88789924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 3

Real-time DSP implementation of motion-JPEG2000 using overlapped block transferring and parallel-pass methods 运动- jpeg2000的实时DSP实现采用重叠块传输和并行通道方法

Real-Time Imaging Pub Date : 2004-10-01 DOI: 10.1016/j.rti.2004.08.003

Byeong-Doo Choi, Kang-Sun Choi, Min-Cheol Hwang, Jun-ki Cho, Sung-Jea Ko

{"title":"Real-time DSP implementation of motion-JPEG2000 using overlapped block transferring and parallel-pass methods","authors":"Byeong-Doo Choi, Kang-Sun Choi, Min-Cheol Hwang, Jun-ki Cho, Sung-Jea Ko","doi":"10.1016/j.rti.2004.08.003","DOIUrl":"10.1016/j.rti.2004.08.003","url":null,"abstract":"<div><p><span><span>This paper presents a real-time implementation of Motion-JPEG2000 encoder using a fixed-point DSP chip. Among several modules in JPEG2000 encoder, the lifting algorithm for discrete wavelet transform (DWT) and the embedded block coding with optimized truncation (EBCOT) comprise more than 85% of the encoding complexity. Thus, it is very important to design and optimize these two modules in order to increase the performance of the hardware implementation. First we propose an overlapped block transferring (OBT) method that can significantly improve the performance of the lifting algorithm for DWT by increasing the </span>cache hit rate. We show that the execution time of the lifting scheme can be further reduced by programming the DSP software using the </span>single instruction multiple data (SIMD) instructions and the super scalar pipeline structure. Moreover, we introduce a parallel-pass method for fast implementation of EBCOT. This method reduces the processing time of EBCOT by processing the three coding passes of the same bit-plane in parallel. Experimental results show that our developed Motion-JPEG2000 DSP system meets the common requirement of the real-time video coding [30 frames/s (fps)] and is proven to be a practical and efficient DSP solution.</p></div>","PeriodicalId":101062,"journal":{"name":"Real-Time Imaging","volume":"10 5","pages":"Pages 277-284"},"PeriodicalIF":0.0,"publicationDate":"2004-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.rti.2004.08.003","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84127452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 12

An embedded wavelet image coder with parallel encoding and sequential decoding of bit-planes 一种嵌入式小波图像编码器，具有位平面并行编码和顺序解码

Real-Time Imaging Pub Date : 2004-10-01 DOI: 10.1016/j.rti.2004.08.006

Yufei Yuan, Mrinal K. Mandal

{"title":"An embedded wavelet image coder with parallel encoding and sequential decoding of bit-planes","authors":"Yufei Yuan, Mrinal K. Mandal","doi":"10.1016/j.rti.2004.08.006","DOIUrl":"10.1016/j.rti.2004.08.006","url":null,"abstract":"<div><p><span><span>Wavelet-based coders are widely used in image compression. Many popular embedded wavelet coders are based on a </span>data structure<span> known as zerotree. However, there exists another category of embedded wavelet coders that are fast and efficient without employing zerotree. These coders are based on three key concepts: (1) wavelet coefficient reordering, (2) bit-plane partitioning, and (3) encoding of bit-planes with certain efficient variants of run-length coding. In this paper, we propose a novel method to construct a bit-plane encoder that can be used in this category of non-zerotree coders. Instead of encoding the bit-planes progressively, the bit-plane encoding process can be finished in one pass when multiple bit-plane encoders are activated concurrently. With this proposed method, traditional partitioned-block based </span></span>parallel processing<span> strategy is enhanced with another dimension (depth of bit-planes) of processing flexibility. This bit-plane encoder inherently targets parallel processing architecture. The final output bitstream can be compatible with that of the original sequential coder if compatibility is preferred over speed and memory efficiency.</span></p></div>","PeriodicalId":101062,"journal":{"name":"Real-Time Imaging","volume":"10 5","pages":"Pages 285-295"},"PeriodicalIF":0.0,"publicationDate":"2004-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://sci-hub-pdf.com/10.1016/j.rti.2004.08.006","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77286436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

A scalable video codec for layered video streaming 一个可扩展的视频编解码器，用于分层视频流

Real-Time Imaging Pub Date : 2004-10-01 DOI: 10.1016/j.rti.2004.08.005

Wei Feng, Ashraf A. Kassim, Chen-Khong Tham

引用次数: 0