使用ffmpeg+dxva2实现H.264硬解码 SDK，支持同时多路并行解码。(Using ffmpeg+dxva2 to achieve H.264 hard decoding SDK, support simultaneous multi-channel parallel decodin)

可在瑞芯微平台上实现视频硬解码，降低cpu占比，并可多路同时使用mpp h264编解码库进行硬解码。开源库，支持C/C++语言，支持Linux/Unix/Windows平台。(Hard video decoding can be implemented on the Rockchip Micro-Platform to reduce the proportion of CPU, and MPP H264 codec library can be used in multi-channel har