在3D 視訊影片中，使用彩色影像加深度影像可以產生虛擬視角，每一個彩
色影像和所產生的虛擬視角組成了立體影像對，利用立體視覺影像系統來產生出
3D 的場景。本篇論文提出了一個在新一代視訊壓縮標準—高效能視訊編碼(High
Efficiency Video Coding, HEVC) 中壓縮深度影像的快速模式決策演算法，此快速
模式決策演算法使用了Zhao 等人所提出的深度合成無錯模組來決定所需要執行
的最小編碼單位，同時保持不錯的影像品質。實驗結果說明了在計算時間複雜度
上，本篇論文所提出的快速模式決策演算法比起HEVC 有顯著的改善，並且僅損
失微量的影像品質以及增加少量的位元率。

In 3-D video sequences, color plus depth-maps are used to generate virtual views. Each color map as well as the generated virtual view constitute a stereo pair to create a 3D scene by the stereoscopic video system. This thesis presents a fast mode decision algorithm for compressing depth-maps in HEVC (High Efficiency Video Coding). The proposed mode decision algorithm determines the minimum coding-unit size in the quadtree structure of HEVC as early as possible while preserving an acceptable quality by using Zhao et al.'s depth no-synthesis-error model. Experimental results demonstrate that the proposed mode decision algorithm significantly outperforms the one in HEVC in terms of computational time complexity while having negligible quality and bitrate performance degradation.

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