The browser based GUI for the bean sorting project is now up and running and being served from the Raspberry Pi. I only have one camera running right now because I only have one camera, but it does all the things that need to be done. There is a lot underneath the hood on this thing, so it should serve as a good base for other embedded machine vision projects beside this one.
In terms of particulars, I am using a Flask (Python3)/uWSGI/nginx based program that runs as a service in the Raspberry Pi. Users access this service wirelessly (anywhere from the internet). The service passes these access requests to the C++/OpenCV based vision application which is also running as a service on the Raspberry Pi. Currently, we can snap images show “live” video, read the C++ vision log, and do other such tasks. We probably will use something other than a Raspberry Pi for the final product with a USB 3.0 port and the specific embedded resources we need, but the Raspberry Pi as been great for development and will do a great job for prototypes and demonstration work.
The reason I put the “live” of “live” video in scare quotes is that I made the design decision not to stream the video with gstreamer. In the end applications I will be processing 1 mega-pixel images at 20-30 frames per second which is beyond the bandwidth available for streaming at any reasonable rate. The purpose of the live video is for camera setup and to provide a little bit of a reality check at runtime by showing results for each 30th to 100th image as a reality check along with sort counts. There is no way we could stream the images at processing rates and we want to see something better than the degraded streamed image.