Design and Implementation of a Distributed Video Encoder

分散式視訊編碼是一個有別於傳統視訊架構的視訊編碼，他的特色是低運算複雜度的編碼器，然而存在著兩個不同的問題。因此為了處理這兩個問題，我們分別提出不同的方法去解決。第一個問題為分散式視訊編碼採用低功耗及低成本的編碼器，但是無法在適用的情境下利用軟體解達到即時編碼的速度。因此我們實作一個混合型分散式視訊編碼的編碼器晶片，並且能達到每秒編碼30幀1080p的影像。另外一個問題是編解碼時間的極度不平衡，因此低複雜度的移動評估被加入演算法中來解決這個問題。解碼時間平均上可以減為原來的一半，使得編解碼的時間可以更加平衡，而且碼率-失真曲線可以得到提升。Distributed Video Coding (DVC) is a novel scheme which is different from the state-of-the-art video compression standards. The characteristic of DVC is that there is a low computational complexity encoder. However, there are two issues on the DVC. The first issue is that DVC encoder cannot perform real-time encoding at suitable situations. In order to solve this issue, a hardware architecture of the DVC encoder with a high resource-sharing is proposed in this work to support the real-time encoding of 1080p (1920 1080) video at 30 frames per second. Besides, this hardware architecture also supports the H.264/AVC intra-frame encoding. The other issue is that imbalance coding time exists between the encoder and the decoder. Low-complexity motion estimation algorithm and skip mode have been applied to the encoder of DVC to reduce half of the decoding time. Besides, the rate-distortion performance is improved in high motion videos