分析了受損宏塊的信道失真及其差錯(cuò)擴(kuò)散，研究了宏塊編碼模式對(duì)信源失真和信道失真的影響，提出了結(jié)合信源信道編碼的一種基于率失真優(yōu)化的快速模式選擇算法。通過估算不同宏塊模式的信源失真和信道失真，自適應(yīng)地選擇最佳編碼模式，使得視頻序列的整體傳輸失真最小。模擬實(shí)驗(yàn)顯示，相對(duì)于H.264參考軟件的模式選擇算法，該算法顯著降低了計(jì)算復(fù)雜度并提高了視頻差錯(cuò)恢復(fù)性能。
關(guān) 鍵 詞 視頻傳輸; H.264/AVC; 模式選擇; 率失真優(yōu)化

Abstract The channel distortion and error propagation of damaged macroblock are analyzed. The impact of macroblock modes on source distortion and channel distortion is discussed，and thus a fast macroblock mode selection algorithm is proposed based on joint source-channel rate distortion optimization. By evaluating the channel distortion and source distortion of all macroblock modes, the optimal macroblock mode is selected adaptively to minimize transmission distortion. Compared with the mode selection algorithm in H.264 reference software, our simulation results show that the proposed algorithm reduces computational complexity significantly and gets better error resilient.
Key words video transmission; H.264/AVC; mode selection; rate distortion optimization