Being able to remove window decoration (the bar with the minimize/maximize buttons and name, and any window border) from a highgui namedWindow would be ideal, but that doesn't seem possible.
I'm currently considering using SDL which I think SDL_NOFRAME and SDL_SetVideoMode() solves my problem, but I'm curious if there is a faster or easier way. I don't want it to be too difficult to convert the cv::Mat to the new format, and it should also be high performance (low-latency and 10s of fps framerate).
This is using Linux and X windows, so making X calls would be acceptable.