In order to solve them , a new motion estimation algorithm based on macroblock partition is proposed in this paper , and a new rate control policy is adopted . simulations show that the proposed algorithms can improve system coding efficiency and image quality 为了有效地对块效应进行消除，本文提出了一种新的宏块预测分区运动估值算法并采用了一种新的码率控制策略，实验结果表明改进算法在图像质量上优于原算法。
By integrating motion compensation and recompose frame , classifying the integration according to the mode of macroblock coding and motion compensation integration , and combination in another way to achieve to improve the performance of decoder 在对idct优化过程中提出了一种结合vlcd (变长码解码)和iq (反量化)解码过程的优化方法；把运动补偿和图像重组过程结合在一起，按图像编码方式和运动补偿方式进行分类组合，实现解码性能提高。
According to the complexity threshold , we auto - adaptatively adjust the qp . we use the smaller qp to quantify the more complicated macroblock and use the bigger qp to quantify the less complicated macroblok . the proposed algorithm can improve the h . 264 standard algorithm by a rate control algorithm on macroblock layer 在宏块层利用了现有mad值表示宏块复杂度,进一步根据宏块的复杂度阈值自适应地调整量化参数qp ,对复杂度高的宏块采用较小的qp值,进行精细量化;对复杂度低的qp值采用较大的qp值,以节约比特数。
In packet based wireless video communications , when best band distribution , not only source distortion should be considered , but also channel distortion caused by channel errors . the existing macroblock - layer rate control schemes calculates quantization parameters of all macroblocks ( mb ) in a frame in a raster scan order , and then encodes the mbs in the same order . actually , the quantization distortion is heavily dependent upon the coding order of mbs 在基于包的无线视频传输中，最佳带宽分配时，不仅要考虑信源编码失真，也要考虑由于信道差错引起的信道失真；已有的宏块层码率控制算法以矩阵扫描的顺序计算一帧中所有宏块的量化参数，事实上量化失真与宏块的编码顺序有很大关系，改变宏块的编码顺序，使复杂的宏块分配到更多的比特数，显然能大大提高编码效率。
Compared with the traditional pixel domain video transcoding , the transcoding from hdtv to sdtv in the dct domain , not only avoids the dct and idct transforms , but also avoids motion estimation , the most computation costing process , by making full use of the macroblock motion vector information from the input hdtv stream to construct the motion vector for the according sdtv macroblocks . it ’ s helpful to achieve the hdtv to sdtv video transcoding in the real time Dct域hdtv至sdtv视频转码,与传统的像素域转码相比,不仅避免了dct 、 idct运算,还通过利用输入hdtv码流中宏块的运动矢量信息直接构造转码后sdtv相应宏块的运动矢量,避免了运算量极大的运动估计过程,有利于hdtv至sdtv实时转码的实现。
In intra - frame postprocessing error concealment techniques in this dissertation , interpolating pixel values within a damaged macroblock from its four 1 - pixel - wide boundaries and introducing the texture information from its four adjacent blocks can improve the quality of reconstructed image . it was found that the visual texture in damaged macroblocks can be reconverted with his algorithm in experiment 本文提出的一种基于视频帧内后处理的错误隐藏算法，采用帧内纹理恢复的内插技术，将相关性最强的象素作为损坏块内插的信息源，并引入相邻块的纹理信息，从而获得较好的图象恢复质量。
