The Great Refactor (OpenVINO 2021.1)

[AndBobsYourUncle]

With OpenVINO 2021 (and likely sooner), there were some massive changes to the framework, and also some pretty awesome additions to the Open Model Zoo.

The new abstractions and additions to the Open Model Zoo samples allows this project to simply link in to those exposed classes when building this project. Also, the multi-threading and multiple camera handling is now done entirely by their framework, hopefully adding quite a boost in processing speed.

Namely, they expose a "pipeline" class that handles submissions of images to run through the neural network, along with some metadata. We can then create our own, new metadata class that adds in a camera index.

In this way, when the pipeline returns back a fully processed frame, it comes back with the camera index. So, we simply iterate through all cameras, passing in a frame from each into the pipeline (with the metadata of the camera index), and when they come back (even out of order), we know which ones were for which cameras.

This greatly simplifies the code.