Device for streaming HDMI signal over the network?

Question

RTMP

In general, the task is simple: you need to stream the incoming HDMI signal to the network so that you can process it on the fly and stream the result on your computer. So far, I have googled ready-made encoders like VidiU / BoxCaster / DMB-8800A, but the prices of $ 500 are too much. On Ali, of course, there are options for $ 200, but I would like it even cheaper, because now there are enough single-payers and dongles for $ 30-100 whose iron would cope with such a task.