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,按一下以編輯母片標題樣式,按一下以編輯母片,第二層,第三層,*,MPEG-7 Overview-part 2,1,MPEG-7 Overview-part 21,Review,Descriptor(D),-,對內容的特徵作定義,。,-,通常用以描述low-level features,。,Description Scheme(DS),-,通常用以描述 high-level features。,-,DS和D的區別是：D僅包含基本的資料類型，而DS可,同時包含D與 DS。,2,ReviewDescriptor(D)2,Review(contd.),D、DS與DDL之關係圖如下:,D,D,D,DS,DS,D,D,D,DS,DDL,3,Review(contd.)D、DS與DDL之關係圖如下,DDL(Description Definition Language),The DDL defines the syntactic rules to express and combine DSs and Ds.,The DDL is not a modeling language but a,schema language,to represent the results of modeling audiovisual data,i.e.DSs and Ds.,In March 2000,MPEG was decided to adopt XML Schema Language as the MPEG-7 DDL.,4,DDL(Description Definition L,DDL(contd.),However,XML Schema language has not,been designed specifically for AV content,certain extensions have been necessary.,Array and matrix datatypes,Built-in primitive time datatypes,5,DDL(contd.)However,XML Schem,BiM,XML has not been designed to deal ideally in a real-time,constrained and streamed environment.,To overcome it,MPEG-7 Systems defines a generic framework to facilitate the carriage and processing of MPEG-7 descriptions:,BiM,(Binary Format for MPEG-7).,6,BiMXML has not been designed t,BiM(contd.),The features of BiM are:,BiM binary format is not dedicated to any specific,XML language.,BiM is a schema oriented encoding scheme.,BiM is a pre-parsed format,BiM allows a parameterized transmission of XML,document,like depicted below:,Fig.,Different streaming strategies of the same XML file,7,BiM(contd.)The features of Bi,MPEG-7 Terminal,The entity that makes use of the coded representations of the multimedia content description is referred to as the“terminal”.,The terminal has three main architectural layers:,application layer,system layer,delivery layer,8,MPEG-7 TerminalThe entity that,MPEG-7 Terminal(contd.),An MPEG-7 terminal consumes description streams and outputs a representation of the description called the,current description tree,.,Description streams consist of Access Units(,AUs,).,textual description stream,binary description stream,9,MPEG-7 Terminal(contd.)An MPE,MPEG-7 Terminal(contd.),An AU is composed of any number of Fragment Update(,FU,)Units,each of which is extracted in sequence by the fragment update component extractor.,Each FU unit consists of:,a FU command,a FU context,a FU payload,10,MPEG-7 Terminal(contd.)An AU,MPEG-7 Terminal(contd.),11,MPEG-7 Terminal(contd.)11,Reference Software:the eXperimentation Model,The XM software is the frame work for the for all the reference code of the MPEG-7 standard.,The XM software has only a command line interface,which does not allow any interaction during run-time.,The modules of the XM software are designed in a way,that all modules are using specified interfaces.,12,Reference Software:the eXperi,Reference Software:the eXperimentation Model(contd.),Within the XM software framework,applications are related to one particular descriptor or description scheme.,Server(or extraction)applications,Client applications,13,Reference Software:the eXperi,Application types in the XM software,Extraction from Media,14,Application types in the XM so,Application types in the XM software(contd.),Search&Retrieval Application,15,Application types in the XM so,Application types in the XM software(contd.),Media Transcoding Application,16,Application types in the XM so,Application types in the XM software(contd.),Description Filtering Application,17,Application types in the XM so,The MPEG-7 key application model,Applications,which are implemented in the XM software are also called,key applications,.,The inputs and outputs of key applications are:,18,The MPEG-7 key application mod,Key applications vs.real world applications,In general,combining the key applications will form complex applications.,19,Key applications vs.real worl,MPEG-7 Conformance Testing,MPEG-7 Conformance Testing includes the guidelines and procedures for testing conformance of MPEG-7 implementations.,There are two kinds of conformance testing:,conformance testing for,descriptions,conformance testing for,terminals,20,MPEG-7 Conformance TestingMPEG,MPEG-7 Conformance Testing(contd.),The objective of the conformance testing of,descriptions is to check the syntactic compliance,with ISO/IEC IEC 15938 parts 1 5.,21,MPEG-7 Conformance Testing(co,MPEG-7 Conformance Testing(contd.),The conformance testing for terminal involves the comparison of the result of processing a description using a reference terminal against the result using the test terminal.,22,MPEG-7 Conformance Testing(co,
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