Any complete guides on Codeproject ALPR with TPU?

[totalimpact]

I got Codeproject ALPR working with Blue iris, hoping for better detection speed using a Coral TPU chip, but not getting very far, instructions I have seen are not very complete, not sure what I'm missing.

Am I supposed to disable all other modules in in Codeproject? Did this and get no detection just using Coral Module.

Turned License Plate Reader module back on and get detections, but I get the feeling they are not using the TPU. What model / size should I select in Codeproject, what do I need to change in BI, normally I would have this:


I tested with Coral Dual Edge TPU on a PCIe adapter card, no bifurcation, so single TPU.



I selected the MobileNet SSD model, Small, and disabled Multi-TPU Support. I see these models available in BI:

 

[totalimpact]

After testing with the AI Explorer, I think maybe I am getting the concept wrong, the TPU only does vehicle detection, then passes the vehicle image to the License Plate Reader module for plate OCR.?? So both modules are needed? I think my object settings are wrong on the Alert tab... no idea.

 

[AlwaysSomething]

TPU is only for Object Detection. If you want to use LPR it needs the CPU or a GPU.

Looking at your screenshot I don't think you are using the TPU either but I could be wrong. Usually it says "GPU (TPU)" and not "CPU (TF-Lite)".

Also, there was a bug where the TPU is not using the correct models (it says it is but isn't). I had a post about it on CP before they took down the discussions. Not sure if it was moved to Github. I may have posted the details here too but can't remember. I don't know if that is still there with the latest version but it still existed back in August 2024.

If you want to use LPR and the TPU you can do what I'm doing which is install CPAI and Coral on the BI machine. Then install another copy of CPAI and LPR on another machine (in my case a VM). For the LPR cameras configure the IP of the 2nd machine that has the LPR.