Problem: VideoCapture cannot read avi file and throws error with the Opencv downloaded from Cygwin. I also tried to build Opencv source on my machine for compatibility reason but it failed with undefined function error(linker problem. I tried several way to fix it but failed. I guess it might be related to compatibility with Cygwin)
stack overflow link: https://stackoverflow.com/questions/48288911/videocapture-object-throws-assertion-g-is-object-object-failed-on-cygwin