Hello @Richard Smith,
welcome to this moderated Azure community forum.
According to the documentation of the Azure AI Vision 3.2 GA Read OCR container it can also run on-prem
It can be a computer on your premises or a Docker hosting service in Azure
Notice the hardware requirements in the same documentation.
Azure IoT Edge has a docker runtime and is capable of running 3rd party containers.
There is a separate paragraph regarding running the container disconnected from the cloud. There are extra settings needed in the container create options if using Azure IoT Edge. The structure of those options is not documented so you need to experiment to get that running.
I recommend testing this thoroughly en see what the service offers for you in an edge/offline scenario.
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