基于自適應(yīng)魯棒性光流的差錯掩蓋
Error Concealment Based on Adaptive Robust Optical Flow
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摘要: 編碼數(shù)字視頻序列經(jīng)過受噪聲影響的信道傳輸時,通常會出現(xiàn)圖像信息丟失。該文提出一種基于自適應(yīng)魯棒性光流的差錯掩蓋方法,作為解碼端的工具解決這樣的問題。該文利用光流技術(shù)能有效獲取物體運動估計的特性,對丟失塊進(jìn)行逐像素點的恢復(fù),既避免了圖像模糊,又消除了塊效應(yīng)。在光流的估計中,自適應(yīng)地調(diào)整了目標(biāo)泛函中的數(shù)據(jù)保持項與空間連貫項之間的關(guān)系,并引入Lorentz函數(shù)來構(gòu)造目標(biāo)泛函,提高了光流的魯棒性。仿真結(jié)果表明,該文提出的方法無論在主觀視覺評價,還是在客觀的數(shù)值標(biāo)準(zhǔn)下,都能比現(xiàn)有的誤差掩蓋方法恢復(fù)出質(zhì)量更好的圖像。
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關(guān)鍵詞:
- 圖像處理; 差錯掩蓋; 運動矢量; 光流; 魯棒性估計
Abstract: During transmitting encoded digital video sequences over noisy communication channels, the information of the images will be lost. An error concealment method based on robust optical flow is proposed, as a post-processing tool at the decoder side to solve this problem. The property of optical flow technique on efficiently obtaining motion estimation is used to recover the lost block in pixel-wise manner. This processing not only avoids the image blurring, but also reduces the blocking effect. In the estimation of optical flow, the relation between data conservation term and spatial coherence term of the objective function is adaptively adjusted. In order to increase the robustness, Lorentzian function is used to construct the energy function. Simulation results show that the proposed method can recover the higher quality image on both subjective visual evaluation and objective numerical metrics, comparing to the existing error concealment methods. -
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