具內容互動控制與服務品質認知之MPEG-4 場景編輯器設計與實作

A QoS-aware MPEG-4 authoring Tool with Provision of Content Interaction Control

本論文提出並實作一“具內容互動性與服務品質認知之MPEG-4 場景編輯器”（QoS-Aware MPEG-4 authoring tool with content interaction, Q4AT）。Q4AT透過親和之使用者介面與容易操作特性，讓所有使用者可輕易使用Q4AT 編輯出複雜之MPEG-4 場景。相關之功能設計包括：(1)以標準BIFS（binary format forscene）語法撰寫場景描述（scene description, SD）；(2)以同步描述語言（syntacticdescription language, SDL）撰寫物件描述（object description, OD）； (3)使用Digimax、IBM 與ENST 等著名組織提供之MPEG-4 播放器預覽場景畫面，有效加強編輯準確度與達成系統驗證性；(4)支援定義物件優先權屬性，作為網路傳輸與遠端使用者互動的依據，降低延遲（delay）與間差（jitter）誤差值。此外，Q4AT 所提供介面化場景編輯系統讓場景開發編輯者不需考慮底層程式設計問題，可專注於應用層系統使用方式，有效地降低製作MPEG-4 多媒體檔案之門檻，加速開發相關之多媒體應用程式。

This paper proposes and implements a QoS-Aware MPEG-4 AuthoringTool (Q4AT) with provision of content interaction control. Q4AT providesa user-friendly user interface in the manner of “what you see is what youget” for users to create their favorite MPEG-4 scenes. The characteristics ofQ4AT are as follows: (i) The description of a scene is based on the standard BIFS language. (ii) The creation of the object description is based on thesyntactic description language. (iii) All descriptions are VRML-based. AVRML-based system is compatible with different browsers and operationsystems. Therefore, authors can simplify the steps of creating an MPEG-4scene. (iv) Q4AT supports the functions of the quality of service (QoS) bythe proposed object priority differentiation control. Using Q4AT, theMPEG-4 processing layers are transparent to the author and the author iscapable of concentrating on the editing function usage of the Q4AT. Q4ATmakes it possible to easily create a complicated MPEG-4 scene and reducesthe difficulty of MPEG-4 media creation and presentation.