Opencv 4 h.264 decode delay

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Hi, I'm using OpenCV 4 (Compiled with MSVC 15-64bit + CUDA 10) and VideoCapture class to decode the h.264 stream, but there is about 5 seconds delay in displaying frames. unfortunately my camera doesn't support mjpg and I have to use h.264. I've read about this problem in different sites but all of them was old (2014 or 2012 for example using cv::cudacodec), so I'm wondering if there is a new solution for this problem or not?