近年來嵌入式系統發展快速，圖形處理需求也大幅提升。圖形處理器在嵌入式系統上除了提供多元特效組成的使用者介面，在應用程式及遊戲互動上也相當重要。與個人電腦上之圖形處理單元相比，嵌入式系統運算效能較低。因此，遠端渲染的技術由此概念生成，透過伺服器上圖形處理單元，提高嵌入式系統繪圖效能。而在電腦與嵌入式系統之間，常透過網際網路方式連結。當使用遠端渲染時，常需要較高的網路頻寬，但在網路頻寬不穩定時，遠端渲染可提升之效能將受到限制。在當前研究上，有許多減少資料傳輸之相關研究，但在網路頻寬不穩定上，仍缺乏解決方式。
鑑此，本研究提出一混合式渲染架構，藉由用戶端圖像處理能力，結合伺服器圖形處理單元進行混合式渲染。在網路頻寬不穩定時，評估當前頻寬，動態地配置渲染畫面於用戶端及伺服器。在用戶端無法存取網路時，仍可透過本機端圖形處理單元進行繪圖。本研究將此混合式渲染架構透過系統函式庫實現，並符合標準OpenGL ES架構。本研究測試三種應用程序，高於最低限制10%頻寬下，平均可提升44.99%畫面更新速率；於最低限度網路頻寬下，平均可提升44.57%畫面更新速率；在低於最低限制10%頻寬下，平均可提升30.86%畫面更新速率；在非穩定頻寬下，平均可提升33.74%畫面更新速率。

Due to the fast development of embedded system, the requirement of graphics processing has grown rapidly in recent years. Graphic processing unit provides the computing of 3D effect in embedded system, such as user interface and 3D application. Comparing with personal computer, the computing power in embedded is much lower. The concept of remote rendering comes to the programmers’ mind. By the way of connecting the graphic processing unit in the server improves the local rendering ability. However, when network bandwidth is unstable or even unreachable, the user experience would extremely drop. In the recent research, there are a couples mount of topics in association with decreasing network packet transmission. In the unstable network environment, the correlation research is still lacking.

This paper proposes a hybrid remote rendering framework. It takes local rendering ability and network bandwidth as input arguments and dynamically sets the frames drawing sequence on client and rendering server. In this research, the experiment chooses 3 applications and runs in 4 different network environments. In the 10% higher than the lowest requirement bandwidth, this framework could improve 44.99% frames in each second. In lowest bandwidth requirement, it could improve 44.57% frames and 30.86% in 10% lower than lowest requirement. In the unstable bandwidth, there are around 33.74% increasing in frame rate.

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