opencv to http mjpeg stream?

I have working opencv4nodejs code to detect camera focus blur using laplacian, median etc. I also have mjpg-streamer working. Both use video0 uvc device on raspi but not at the same time.

I want to run both at the same time so I can view the video stream at a decent rate while opencv picks out a frame now and then to calculate focus blur. The blur values can go to stdout or any other output.

I have tried loopback to generate video1 from video0 using gstreamer with no success.

My current idea is to somehow send video frames from opencv to mjpg-streamer or any other http server. How can I do this?

I know about videowriter but the only examples I can find go to a file or ffmpeg. I looked at ffmpeg/ffserver but it looks slow and complicated. Is it the only solution? I guess I am just looking for options.

Thanks in advance.

Review the OpenCV capture and frame-handling APIs exposed by opencv4nodejs, then compare the issue's mjpg-streamer, GStreamer loopback, and HTTP MJPEG options. There are no repository files or tests named; done would require a decided, maintainable approach for simultaneous camera analysis and HTTP video streaming.

Written by the indexing model from the issue text.