近年來，隨著行動裝置數量的快速成長，許多人都擁有智慧型手機或是平板電腦，且隨著硬體運算效能的增進以及其便利性，越來越多人選擇以行動裝置來取代原本的個人電腦、筆記型電腦，他們利用行動裝置來完成原先在電腦才能做到的事，例如玩遊戲、收看高畫質影音甚至是進行互動式視訊聊天。即使許多使用者使用行動裝置來收看影音串流例如:YouTube, Netflix，但是許多行動裝置在於撥放這些影音串流時，仍有許多的限制以及相容性的問題，例如影音格式、傳輸協議的差異。如何讓行動裝置能夠輕鬆存取現存於網路上龐大的多媒體內容，或是說如何讓行動裝置與原有的多媒體影音串流平台銜接起來，是一個急需解決的問題。而就行動裝置的系統而言，以iOS平台對於多媒體檔案的撥放限制最多。
本篇論文將焦點放在iOS平台上影音媒體編碼和解碼模組的研究以及實作，目的在於打破平台之限制，讓行動裝置能與現有的平台銜接。我們利用iOS平台上現有的應用程式介面(Application Programming Interface)以及FFmpeg這個開源、完整的影音編碼、轉碼套件，來實作即時影音編碼、解碼模組。除此之外，並將此模組運用於開發ShareRoom雲端會議系統之iOS APP，成功整合了現有的多媒體分享平台ShareRoom雲端會議系統與行動裝置。

Along with the popularity of mobile devices recent years, most people have a smart phone or tablet. These devices have replaced personal computers or laptops under some circumstances. People now use mobile devices to do what they did on PC or laptop, such as playing video games, watching high quality online videos, and making video chat. This trend is due to the improvement of computing power and the convenience of mobile devices. Besides, people like to use mobile devices to watch online videos like YouTube or Netflix. However, there are still many barriers among mobile devices and current video streaming platforms. For instance, we cannot receive multimedia content from all current video streaming platforms due to the compatibility of different video streaming format. The integration of mobile devices with streaming platforms is a big issue to be solved. For current mobile operating systems, there are many restrictions on playing media file and video streaming on iOS platform.
In this thesis, we focus on the design and implementation of live streaming encoder and decoder modules on iOS platform. Our goal is to break the restrictions on playing media file and video streaming on iOS platform and integrate mobile devices with current video streaming platforms. FFmpeg, an open sourced library used to encode, decode, mux, and demux video streaming, and the native Application Programming Interfaces(API) are used to design and implement these modules. In addition, we use these modules to develop a ShareRoom video conferencing system APP. Lastly, we successfully integrate mobile devices with ShareRoom video conferencing system.

Abstract I
中文摘要 II
Table of Contents III
List of Figures IV
List of Tables VI
Chapter 1 Introduction 1
Chapter 2 Related Works 3
2.1 Adobe Connect Mobile 3
2.2 ShareRoom 4
Chapter 3 Preliminary 5
3.1 Real Time Messaging Protocol 5
3.1.1 Audio Message Format 6
3.1.2 Video Message Format 7
3.2 H.264 / AVC 8
3.3 MP4 Container Format 10
3.4 FFmpeg 12
Chapter 4 System Architecture and Implementation 13
4.1 System Architecture 13
4.2 System Implementation 15
4.2.1 RTMP Live Streaming Encoder 15
4.2.2 RTMP Live Streaming Decoder 25
4.2.3 RTMP Command Module 33
4.2.4 Graphical User Interfaces 34
Chapter 5 Experiment Results 40
5.1 Experiment Environment 40
5.2 Encoder module 41
5.3 Decoder module 43
5.4 ShareRoom APP 45
Chapter 6 Conclusion and Future Works 47
References 49

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