H.265/HEVC是目前最新的視訊規格，其目標是達到比H.264視訊壓縮標準更高 的 編 碼 效 率，其 適 用 範 圍 更 從 HD(720p 或 1080p) 增加 到 Ultra HD(3840x2160)的影片。此外HEVC提供的編碼單位(coding unit, CU)，其預 設大小從8x8到64x64不等，取代H.264中固定大小的編碼單位(marcoblock, MB)，使得位元率(bitrate)得以下降，卻也大幅增加了計算複雜度。
在影像編碼中，整數運動向量估計(integer motion estimation, IME)佔據了大部分的計算複雜度，若要達到實時計算(real time calculation)，需藉由新穎的演算法來改善。由於 CU 深度資訊存在很高程度空間及時間相關性，我們對此加以統計並分析，最後提出了一個新的快速 深度中斷演算法，並藉由快速決策預測模式來簡化編碼單位的深度運算，最後結果，約可節省編碼軟體 43.03%的編碼時間。

H.265/HEVC is the latest video standard, its goal is to achieve a higher compression coding efficiency than H.264, and its supported resolutions is from HD (720p or 1080p) to Ultra HD (3840x2160). Furthermore, coding unit, CU, is provided in HEVC. Its size is ranging from 8x8 to 64x64, replacing the fixed-size marcoblock in H.264. The new technique results in the decrease in bitrate but the increase in computational complexity.
In video encoding, the Integer Motion vector Estimation, IME, is accounted for most of the computational complexity. In order to achieve real-time computation, it needs a new algorithm to improve it. Since there is a high degree of spatial and temporal correlation in CU depth, the property is taken into statistics and analysis, and finally a new fast CU depth decision is proposed to simplify the computation in depths and faster decide the prediction mode decision, which can save about 43.03% encoding time when running on software.

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