OpenCV 3.0.0 “configure” fails, ffmpeg not downloaded

Question

I get the following error when trying to configure OpenCV using CMAKE on windows:

CMake Warning at cmake/OpenCVUtils.cmake:865 (message):
Download: Local cop         


        

Answer 1

Iam running into the same issue. In my opinion it is an issue through our company network and proxyserver.

So i tried to download the file manually from home and put it on my USB flash drive. Please look into your OpenCV source path. There you can find an structure like ...

"...\3rdparty\ffmpeg\downloads\HASH\opencv_ffmpeg.dll"

CMake tries to download the file, but can't pass through proxy, so the file is 0 Byte and md5 checksum fails.

In "...\OpenCV_SOURCE_FOLDER\3rdparty\ffmpeg" you can find a makefile named "ffmpeg.cmake" with the URL CMake tries to download from. In my case I downloaded the file from the following URL:

https://raw.githubusercontent.com/Itseez/opencv_3rdparty/89c783eee1c47bfc733f08334ec2e31c/ffmpeg/opencv_ffmpeg.dll

Your checksum parameter could be different (depending probably on your OpenCV version)! It is possible that you have to do the same for "opencv_ffmpeg_64.dll" and "ffmpeg_version.cmake".

Best regards