配置opencv源时Cmake的问题

Question

我按照此链接https://docs.opencv.org/3.1.0/d5/de5/tutorial_py_setup_in_windows.html

为图像处理项目安装了opencv2，python，cmake和visual studio

但是在cmake中进行配置时会显示以下错误

CMake Warning at cmake/OpenCVUtils.cmake:872 (message):
Download: Local copy of opencv_ffmpeg.dll has invalid MD5 hash:
d41d8cd98f00b204e9800998ecf8427e (expected:
89c783eee1c47bfc733f08334ec2e31c)
Call Stack (most recent call first):
3rdparty/ffmpeg/ffmpeg.cmake:10 (ocv_download)
cmake/OpenCVFindLibsVideo.cmake:206 (include)
CMakeLists.txt:536 (include)


Downloading opencv_ffmpeg.dll...
CMake Error at cmake/OpenCVUtils.cmake:895 (file):
file DOWNLOAD HASH mismatch

for file: 


[D:/opencv/sources/3rdparty/ffmpeg/downloads/89c783eee1c47bfc733f08334ec2e31c/opencv_ffmpeg.dll]
      expected hash: [89c783eee1c47bfc733f08334ec2e31c]
        actual hash: [d41d8cd98f00b204e9800998ecf8427e]

Call Stack (most recent call first):
3rdparty/ffmpeg/ffmpeg.cmake:10 (ocv_download)
cmake/OpenCVFindLibsVideo.cmake:206 (include)
CMakeLists.txt:536 (include)


CMake Error at cmake/OpenCVUtils.cmake:899 (message):
Failed to download opencv_ffmpeg.dll.  Status=6;"couldn't resolve host name"
Call Stack (most recent call first):
3rdparty/ffmpeg/ffmpeg.cmake:10 (ocv_download)
cmake/OpenCVFindLibsVideo.cmake:206 (include)
CMakeLists.txt:536 (include)

有人知道如何解决这个问题吗？