配置opencv contrib 提示缺少ffmpeg问题解决

3rdparty/ffmpeg/downloads/89c783eee1c47bfc733f08334ec2e31c/opencv_ffmpeg.dll

1、将opencv\\build\bin\下的opencv_ffmpeg310.dll和opencv_ffmpeg310_64.dll拷贝到报错提示的下载路径,我的是:opencv\sources\3rdparty\ffmpeg\downloads\89c783eee1c47bfc733f08334ec2e31c

2、将opencv\sources\3rdparty\ffmpeg\ffmpeg.cmake文件内容用记事本修改为

set(HAVE_<span style="color: black; background-color: rgb(153, 255, 153);">FFMPEG</span> 1)
set(HAVE_<span style="color: black; background-color: rgb(153, 255, 153);">FFMPEG</span>_CODEC 1)
set(HAVE_<span style="color: black; background-color: rgb(153, 255, 153);">FFMPEG</span>_FORMAT 1)
set(HAVE_<span style="color: black; background-color: rgb(153, 255, 153);">FFMPEG</span>_UTIL 1)
set(HAVE_<span style="color: black; background-color: rgb(153, 255, 153);">FFMPEG</span>_SWSCALE 1)
set(HAVE_<span style="color: black; background-color: rgb(153, 255, 153);">FFMPEG</span>_RESAMPLE 0)
set(HAVE_GENTOO_<span style="color: black; background-color: rgb(153, 255, 153);">FFMPEG</span> 1)

set(ALIASOF_libavcodec_VERSION 56.41.100)
set(ALIASOF_libavformat_VERSION 56.36.101)
set(ALIASOF_libavutil_VERSION 54.27.100)
set(ALIASOF_libswscale_VERSION 3.1.101)
set(ALIASOF_libavresample_VERSION 2.1.0)

另外一种是使用这种：https://raw.githubusercontent.com/Itseez/opencv_3rdparty/8aeefc4efe3215de89d8c7e114ae6f7a6091b8eb/ffmpeg/ffmpeg_version.cmake