為了在異質而多樣的網路環境下進行視訊串流，可調式視訊編碼定義了一個可調性的視訊編碼。在不同的傳輸環境之下，SVC可以動態地改變傳遞視訊大小、影像品質跟畫面更新頻率以配合不同的傳輸環境。在頻寬不足的情況下，透過截斷位元流的方式，SVC可以優雅地降低視訊品質。但是目前的編碼方式雖然提供了很好的可調性，但是在感興趣區域 (ROI, Region of Interest) 的編碼上，缺少更細緻化的編碼方式跟編碼率控制的方法。
本論文在SVC的網路傳輸層中，修改截斷位元流的方式，以提供在感興趣區域的影像更好的影像品質。在低位元率的情況下，整個還原的影片畫面中，感興趣區間中可以依照畫面的精細程度動態增加單純畫面區域的資料量，以增加影像品質，感興趣區間中相對畫面複雜區域的部分減少它的資料量，以節省頻寬。在這樣的架構下，本論文在實驗中也證明在動態分配的機制下，在感興趣區間的影像品質可獲得更好的提升。

For video streaming within heterogeneous and various network environments, Scalable Video Coding (SVC) has defined a scalable video coding. Under different transmission environments, SVC dynamically alters video resolution, image quality and frame rate, to adopt the different network environments. In addition, SVC gracefully lowers video quality through the method of bit rate intercept under the circumstance of insufficient bandwidth. Although the coding scheme offers excellent scalability nowadays, the ROI (Region of Interest) coding still lacks for detailed coding scheme and coding efficiency.
This study modified the mode of bit stream truncation inside SVC transport layer to provide the better quality of ROI coding. To reconstruct frame in the low-bit-rate circumstances, ROI coding could dynamically increase the data of simple frame region based on the sophistication of frames to improve the image quality; meanwhile, complex region of relative frame in ROI decreased its data for saving bandwidth. Under such framework, this study also found that the image quality in ROI could get better improvement under the dynamic allocation mechanism.

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