Multi-pass decoder-side motion vector refinement

Example apparatus and techniques for multi-pass decoder side motion vector refinement (DMVR) are disclosed. An example apparatus includes a memory configured to store video data and one or more processors coupled to the memory. The one or more processors are configured to apply the multi-pass DMVR to a motion vector of a block of video data to determine at least one refined motion vector, and to decode the block based on the at least one refined motion vector. The multi-pass DMVR includes a first pass based on a block, a second pass based on a sub-block, and a third pass based on the sub-block. 公开了用于多遍次解码器侧运动向量细化(DMVR)的示例设备和技术。一种示例设备包括被配置为存储视频数据的存储器和耦合到存储器的一个或多个处理器。一个或多个处理器被配置为将多遍次DMVR应用于视频数据的块的运动向量，以确定至少一个细化的运动向量，并基于至少一个细化的运动向量对块进行解码。多遍次DMVR包括基于块的第一遍次、基于子块的第二遍次和基于子块的第三遍次。