VideoCapture not working with DSHOW backend
(This is a duplicate of SO)
I built OpenCV (with mingw 4.9.2 @ Win7Prof64) with CMake switches for WITH_FFMPEG and WITH_DSHOW turned on. When I access a movie file with
VideoCapture (fileName)
works fine (it uses ffmpeg backend then).
But
VideoCapture (fileName, cv::CAP_DSHOW)
doesn't work (isOpened() returns false).
What is missing/ what do I do wrong? Are there any kind of dshow stubs/ libs/ dlls needed?
VideoCapture (fileName);will use opencv_ffmpeg.dll to decode the video (which covers almost any container/codec on earth), while
will try to use your locally (os-)installed directshow codecs. you probably do not have one for the file you want to open.Thank you for your answer. But missing directshow codecs (I use the K-Lite distr. since years) is not the reason for sure. To me it seems like a missing connection (stub etc.) between opencv and the local directshow interface. Configuration issues in the directshow system didn't help.
please ignore the prev. post, i was entirely wrong, sorry.
it seems, you're right, there is simply no dshow branch here , also no code for opening videos in cap_dshow.cpp