《ANSI-ISO-IEC-TR-14496-7-2002.pdf》由会员分享，可在线阅读，更多相关《ANSI-ISO-IEC-TR-14496-7-2002.pdf（22页珍藏版）》请在三一文库上搜索。
1、Adopted by INCITS (InterNational Committee for Information Technology Standards) as an American National Standard.Adopted by INCITS (InterNational Committee for Information Technology Standards) as an American National Standard. Date of ANSI Approval: 11/30/2003 Published by American National Standa
2、rds Institute, 25 West 43rd Street, New York, New York 10036 Copyright 2003 by Information Technology Industry Council (ITI). All rights reserved. These materials are subject to copyright claims of International Standardization Organization (ISO), International Electrotechnical Commission (IEC), Ame
3、rican National Standards Institute (ANSI), and Information Technology Industry Council (ITI). Not for resale. No part of this publication may be reproduced in any form, including an electronic retrieval system, without the prior written permission of ITI. All requests pertaining to this standard sho
4、uld be submitted to ITI, 1250 Eye Street NW, Washington, DC 20005. Printed in the United States of America Reference number ISO/IEC TR 14496-7:2002(E) ISO/IEC 2002 TECHNICAL REPORT ISO/IEC TR 14496-7 First edition 2002-12-01 Information technology Coding of audio-visual objects Part 7: Optimized ref
5、erence software for coding of audio-visual objects Technologies de linformation Codage des objets audiovisuels Partie 7: Logiciel de rfrence optimis pour le codage des objets audiovisuels Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair
6、 Facility Yokosuka/9961031100 Not for Resale, 05/08/2007 23:30:01 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO/IEC TR 14496-7:2002(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or
7、viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer performing the editing. In downloading this file, parties accept therein the responsibility of not infringing Adobes licensing policy. The ISO Central Secretariat accepts no liability
8、 in this area. Adobe is a trademark of Adobe Systems Incorporated. Details of the software products used to create this PDF file can be found in the General Info relative to the file; the PDF-creation parameters were optimized for printing. Every care has been taken to ensure that the file is suitab
9、le for use by ISO member bodies. In the unlikely event that a problem relating to it is found, please inform the Central Secretariat at the address given below. ISO/IEC 2002 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by a
10、ny means, electronic or mechanical, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs member body in the country of the requester. ISO copyright office Case postale 56 CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax + 41 22 749 09 47 E-mail
11、 copyrightiso.ch Web www.iso.ch Printed in Switzerland ii ISO/IEC 2002 All rights reserved Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/08/2007 23:30:01 MDTNo reproduction or networkin
12、g permitted without license from IHS -,-,- ISO/IEC TR 14496-7:2002(E) ISO/IEC 2002 All rights reserved iii Contents Page 1 Scope 1 2 Fast Motion Estimation.1 2.1 Introduction to Motion Adaptive Fast Motion Estimation.1 2.2 Technical Description of Core Technology MVFAST2 2.2.1 Detection of stationar
13、y blocks.2 2.2.2 Determination of local motion activity .2 2.2.3 Search Center3 2.2.4 Search Strategy .3 2.2.5 Perspectives on implementing MVFAST .4 2.2.6 Special Acknowledgements4 2.3 Technical Description of PMVFAST.5 2.3.1 Introduction.5 2.3.2 Technical Description of PMVFAST5 2.3.3 Special Ackn
14、owledgement6 2.4 Conclusions6 3 Fast Global Motion Estimation.7 3.1 Introduction to Feature-based Fast and Robust Global Motion Estimation Technique .7 3.2 Technical Description of FFRGMET.8 3.2.1 Outlier Exclusion8 3.2.2 Robust Object Function 8 3.2.3 Feature Selection.8 3.2.4 Algorithm Description
15、 8 3.2.5 Perspectives on implementing FFRGMET.9 3.2.6 Special Acknowledgements9 3.3 Conclusions9 4 Fast and Robust Sprite Generation10 4.1 Introduction to Fast and Robust Sprite Generation10 4.2 Algorithm Description .10 4.2.1 Outline of Algorithm.10 4.2.2 Image Region Division .11 4.2.3 Fast and Ro
16、bust Motion Estimation11 4.2.4 Image Segmentation12 4.2.5 Image Blending.12 4.3 Conclusions13 5 Contact Information13 Bibliography 14 Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/08/20
17、07 23:30:01 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO/IEC TR 14496-7:2002(E) iv ISO/IEC 2002 All rights reserved Foreword ISO (the International Organization for Standardization) and IEC (the International Electrotechnical Commission) form the specialized system f
18、or worldwide standardization. National bodies that are members of ISO or IEC participate in the development of International Standards through technical committees established by the respective organization to deal with particular fields of technical activity. ISO and IEC technical committees collab
19、orate in fields of mutual interest. Other international organizations, governmental and non-governmental, in liaison with ISO and IEC, also take part in the work. In the field of information technology, ISO and IEC have established a joint technical committee, ISO/IEC JTC 1. International Standards
20、are drafted in accordance with the rules given in the ISO/IEC Directives, Part 3. The main task of the joint technical committee is to prepare International Standards. Draft International Standards adopted by the joint technical committee are circulated to national bodies for voting. Publication as
21、an International Standard requires approval by at least 75 % of the national bodies casting a vote. In exceptional circumstances, the joint technical committee may propose the publication of a Technical Report of one of the following types: type 1, when the required support cannot be obtained for th
22、e publication of an International Standard, despite repeated efforts; type 2, when the subject is still under technical development or where for any other reason there is the future but not immediate possibility of an agreement on an International Standard; type 3, when the joint technical committee
23、 has collected data of a different kind from that which is normally published as an International Standard (“state of the art”, for example). Technical Reports of types 1 and 2 are subject to review within three years of publication, to decide whether they can be transformed into International Stand
24、ards. Technical Reports of type 3 do not necessarily have to be reviewed until the data they provide are considered to be no longer valid or useful. Attention is drawn to the possibility that some of the elements of this Technical Report may be the subject of patent rights. ISO and IEC shall not be
25、held responsible for identifying any or all such patent rights. ISO/IEC TR 14496-7, which is a Technical Report of type 3, was prepared by Joint Technical Committee ISO/IEC JTC 1, Information technology, Subcommittee SC 29, Coding of audio, picture, multimedia and hypermedia information. ISO/IEC 144
26、96 consists of the following parts, under the general title Information technology Coding of audio-visual objects: Part 1: Systems Part 2: Visual Part 3: Audio Part 4: Conformance testing Part 5: Reference software Part 6: Delivery Multimedia Integration Framework (DMIF) Part 7: Optimized reference
27、software for coding of audio-visual objects Part 8: Carriage of MPEG-4 contents over IP networks Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/08/2007 23:30:01 MDTNo reproduction or net
28、working permitted without license from IHS -,-,- ISO/IEC TR 14496-7:2002(E) ISO/IEC 2002 All rights reserved v Introduction This part of ISO/IEC 14496 was developed in response to the growing need for optimized reference software that provides both improved visual quality and faster execution while
29、compliance is preserved. The goal is to provide non-normative tools that are essential for implementations of the normative parts of the ISO/IEC 14496 specifications. For example, Part 5 of the ISO/IEC 14496 specifications uses a full search motion estimation which is theoretical optimum in coding e
30、fficiency but impractical for commercial implementation. In the past, the industry needs to create its own encoding tools for its target products. In this part, we provide a well-tested set of encoding tools that can enhance the performance but should not be standardized. The following recommended t
31、ools would be up to the individual organization to decide if it wishes to adopt or adapt these tools for its specific needs. This part provides significant reduction in the time-to-market and provides a reference benchmark for commercial ISO/IEC 14496 compliant products. Copyright American National
32、Standards Institute Provided by IHS under license with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/08/2007 23:30:01 MDTNo reproduction or networking permitted without license from IHS -,-,- Copyright American National Standards Institute Provided by IHS under licens
33、e with ANSI Licensee=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/08/2007 23:30:01 MDTNo reproduction or networking permitted without license from IHS -,-,- TECHNICAL REPORT ISO/IEC TR 14496-7:2002(E) ISO/IEC 2002 All rights reserved 1 Information technology Coding of audio-visual
34、 objects Part 7: Optimized reference software for coding of audio-visual objects 1 Scope This part of ISO/IEC 14496 specifies the encoding tools that both enhance the execution and quality for the coding of visual objects as defined in the ISO/IEC 14496-2. The tool set is not limited to visual objec
35、ts but at this point all the recommended tools are visual encoding tools. There are three tools that have been described in this Technical Report. ? Fast Motion Estimation ? Fast Global Motion Estimation ? Fast and Robust Sprite Generation These tools have been demonstrated as robust tools with sour
36、ce codes for both MoMusys and Microsoft implementations. In the current implementations, there is single software that includes all tools existed in the ISO/IEC 14496-2. This is obvious inefficient in terms of code size and execution speed. To address this issue, there is on-going efforts lead by Na
37、tional Chiao Tung University to enable compilation switches so that only selected tools as defined by the profiles and levels are included. Such level of optimization is still performed at high level programming language. This particular effort will appear in the future amendment of this Technical R
38、eport. The platform specific optimization is currently not addressed by this part. 2 Fast Motion Estimation 2.1 Introduction to Motion Adaptive Fast Motion Estimation The optimization of fast motion estimation is essentially a multi-dimensional problem. The key dimensions concerned in this problem a
39、re: Rate, Quality (PSNR), Speed-up (or Computational Gain), Algorithmic Complexity, Memory Size and Memory Bandwidth (see Figure 1). There always exists a trade-off among all these five key dimensions. Therefore, it is highly desirable to have an adaptive fast motion estimation core algorithm with s
40、calable structure, which can be adaptively optimized with respect to all or selected aspects for various coding environment and requirements. Since the rate control is used to fix the bit-rate, the optimization problem is reduced by one dimension to four dimensions. Motion Vector Field Adaptive Sear
41、ch Technique (MVFAST) 1 is a generic algorithm of the family of motion-adaptive fast search techniques, originally proposed by Kai-Kuang Ma and Prabhudev Irappa Hosur from Nanyang Technological University (NTU), Singapore. The MVFAST offers high performance both in quality and speed and does not req
42、uire memory to store the searched points and motion vectors. The MVFAST has been adopted by MPEG-4 Part 7 in the Noordwijkerhout MPEG meeting (March 2000) as the core technology for fast motion estimation. A derivative of MVFAST, called Predictive MVFAST (PMVFAST) 2, is considered as an optional app
43、roach that might benefit in special coding situations. PMVFAST incorporates a set of thresholds into MVFAST to trade higher speed-up at the cost of memory size, memory bandwidth and additional algorithmic complexity. In PMVFAST, the threshold values are adjusted based on the 54 test cases specified
44、by MPEG-4. However, the coding performance and sensitivity of PMVFAST using these thresholds for the video sequences and encoding conditions outside the MPEG-4 test set has not been studied and verified. Copyright American National Standards Institute Provided by IHS under license with ANSI Licensee
45、=USN Ship Repair Facility Yokosuka/9961031100 Not for Resale, 05/08/2007 23:30:01 MDTNo reproduction or networking permitted without license from IHS -,-,- ISO/IEC TR 14496-7:2002(E) 2 ISO/IEC 2002 All rights reserved Bit-rate Quality Speed Memory (Size and Bandwidth) Algorithmic complexity Figure 1
46、 - Five dimensional optimization problem of fast motion estimation 2.2 Technical Description of Core Technology MVFAST 2.2.1 Detection of stationary blocks A large number of MBs in the video sequences (e.g., “talking head” video sequences) with low-motion content tend to have motion vectors equal to
47、 (0,0). Such MBs in the regions of no-motion activity can be detected simply based on the sum of absolute difference (SAD) at the origin. Therefore, we exploit an optional phase, called early elimination of search, as the first step in MVFAST as follows. The search for a MB will be terminated immedi
48、ately, if its SAD value obtained at (0,0) is less than a threshold T, and the motion vector is assigned as (0,0). Through extensive simulations, we found that among those zero- motion blocks identified, about 98% of them have their SAD at position (0,0) less than 512. Hence, we choose T = 512 to enable the mechanism of early elimination of search. Since this early elimination of search phase is optional, it can be turned off or disabled by imposing T = 0. 2.2.2 Det