For Blue Iris Video Stream tweaks you can go here to not reduce your image quality.
I am still new to home assistant and nodered, however instead of increasing the quality of the video stream from 50% to 100% as outlined in the post above. The below link would give you an image snapshot of 100% quality. You would still need to adjust the Resize output frame width setting and maybe zero frame latency…
http://:/image/?q=100
e.g.
http://192.168.2.216:81/image/FP1?q=100
How would I set that up instead of using your code to convert from mjpg to jpg?