提出了一種近似估計整幀圖像最小量化失真度的模型和新的率失真優化的實時幀內更新準則，可使編碼器直接計算出編碼一幀圖像的最小量化失真度，通過評估宏塊幀內編碼所增加的總量化失真度和減小的擴散失真度，以決定是否需要對此宏塊進行幀內更新。經與傳統的基于率失真的幀內更新相比和實驗結果表明，更新算法在具有更小計算復雜度的同時，在大多數情況下可以取得更好的峰值信噪比值。
關 鍵 詞 視頻編碼; 差錯恢復; 幀內更新; 率失真優化

Abstract A rate-distortion computation model is established for approximately estimating the total quantization distortion of one frame, and a new real time Intra-update criterion is proposed. Through comparing the increased quantization distortion and reduced propagation distortion by intra-updating, the encoder can quickly decide which macroblock need to be intra-updated. Simulation results show that the performance of proposed algorithm, which reduces the computational complexity significantly, achieves the same or even better gains over traditional rate-distortion based Intra-update methods.
Key words video coding; error resilience; intra-update; rate-distortion optimization