MPEG-4 系統及其模擬

Abstract

MPEG-4是為物件化多媒體應用而設計的最新國際標準。MPEG-4第一版國際標準已於1999年4月正式公布。MPEG-4系統是MPEG-4標準規格的第一部份。它定義物件化多媒體元件是如何組成一個完整且富有彈性的呈現。 我的工作可以區分為三個部分：(1) 這個標準是什麼，(2)它如何被實現為軟體程式，以及(3)如何建立測試範例。 我的工作第一個部分是理解MPEG-4系統。他大致上包含了七個部分：系統解壓縮模型，物件描述架構，景描述，元件資料流的同步，元件資料流的多工，合成描述語言及profile。 我的工作第二個部分是追蹤MPEG-4工具及播放程式。這些程式的中心是core code。他可以區分為三個主要部分：核心類別，景類別以及一個一般化用途的樣版函式庫 - ZTL。目前有三個可取得的MPEG-4播放程式，他們每一個都包含超過十萬行的程式碼。 我的工作最後一個部分是使用MPEG-4 工具及播放程式來建立一個範例。我們的測試平台是採用Intel Celeron 300Mhz 的個人電腦，使用的作業系統是微軟視窗九五、九八或NT 4.0。在建立我們的範例的過程中，我們採用3D Studio Max來產生原型測試檔案，然後做一些必要的修正來符合我們的需要。在與MPEG-4軟體經常的改變與持續增加的程式錯誤奮戰許久後，我們終於能夠展示一個三維物件景。

MPEG-4 is the latest international standard for object-based multimedia application. MPEG-4 version 1 international standard was announced at April 1999. MPEG-4 Systems is the first part of the MPEG-4 specification. It defines how object-based multimedia components are combined together to form a complete yet flexible presentation. My task can be divided into 3 phases: (1) what the standard is, (2) how it was implemented, and (3) how to construct test examples. My first task is to study the MPEG-4 Systems. It contains roughly 7 parts: Systems decoder model, Object description framework, Scene description, Synchronization of elementary streams, Multiplexing of elementary streams, Syntactic description language, and Profiles. My second task is to trace the MPEG-4 tools and players. The center of these programs is "the core code". It can be divided into 3 major parts: the core classes, the scene classes, and a general purpose template library - ZTL. There are three MPEG-4 players available; each of them consists of more than 100,000 lines of codes. My last task is using the MPEG-4 tools and players to construct an example. Our testbed is a PC with Celeron 300 MHz processor running Microsoft windows 95/98/NT 4.0. In building our own example, we use 3D Studio Max to produce the prototype file, and make some necessary modifications to meet our own needs. Fighting against constant changes of MPEG-4 Software and ever-growing program bugs, we finally are able to demonstrate a 3-D object scene at the end.