适用于不等保护的自适应视频编码方法

为了提高视频编码效率,同时便于设计有效的不等保护方法,提出一种同时考虑视频内容空间特性和时间特性的视频编码方法.首先确定可表征宏块内容空间特性和时间特性的参数,然后确定反映宏块与空间邻近及时间邻近宏块之间相关性强弱的加权因子,最后将宏块划归到对恢复视频质量影响较大的重要slice组或一般slice组进行编码.与不考虑视频内容特性的编码方法相比,该方法不但可以进一步提高编码效率,而且更有利于识别对恢复视频质量影响较大的宏块,以便利用不等保护方法对这些重要宏块提供较多的保护.实验结果表明,在编码比特率相近的条件下,该方法对恢复视频质量平均提高了0.22 dB和0.46 dB,且在slice组具有相同大小的前提下,该方法定义的重要slice组对恢复视频质量平均提高了1.52 dB和1.20 dB.

An Adaptive Video Coding Method for Unequal Loss Protection

A video coding method is proposed to improve the video coding efficiency and to be favorable for designing efficient unequal loss protection schemes.Both the spatial and the temporal characteristics of video content are considered in the proposed method.Two parameters that embody the spatial and the temporal characteristics of video content are determined,respectively.Then,two weighting factors to reflect the spatial correlation or temporal correlation between the macroblock and its spatial or temporal neighboring macroblocks are determined,respectively.Finally,the macroblocks in one frame are arranged into the important and unimportant slice groups.Compared with the coding method without considering the content characteristics,the proposed method can improve the coding efficiency.Additionally,the important macroblocks are accurately distinguished,and hence more protection can be provided to these macroblocks in unequal loss protection schemes.Simulations show that the proposed method can improve the quality of the decoded video on average 0.22dB and 0.46dB while consuming the similar number of encoded bits.Moreover,under the condition that the two slice groups have the same size,the important slice group marked in the proposed method improves the reconstructed video quality on average by 1.52 dB and 1.20 dB.