三維多項式參數視訊編碼之無線傳輸研究

Abstract

為克服無線通訊的低頻寬限制並增加視訊信號的抗雜訊能力，我們設計了一個名為「三維多項式參數視訊編碼」（3-D PAC）的視訊壓縮方法。在此法中，我們使用多項式來趨近視訊信號，並將其係數送入一個DPCM系統作進一步壓縮。 本論文中我們模擬了無線傳輸的狀況，相較之下，使用同樣的調變技術，此編碼方式的PSNR比視訊電話標準H.263高3dB。 合成此編碼方式的硬體實現較一般MPEG2系統節省約20%，PSNR提昇4.5dB。以軟體實現可以達到每秒20張CIF格式影像的即時解碼。

To overcome the bandwidth limitation and to strengthen the channel effect immunity, a cube-based polynomial video coding scheme for mobile radio transmission is derived, named Three Dimensional Polynomial Approximation Coding (3-D PAC). It also possesses the features of low bit rate of transmission data, robustness for channel fading and simple computation scheme for real-time processing. Compared with the videophone standard H.261, it gains advantage on resisting channel noise to 3 dB with the same bit rate, and the superior subjective performance may be obtained. The hardware complexity of 3-D PAC is 80% of general MPEG2 implementation, while the PSNR of 3-D PAC is even superior to that of MPEG2 by 4.5dB. The simulations of wireless transmission as well as hardware simulation are attached.