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InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
openALPR (Automatic License Plate Recognition) + DCDMV integration + raspberry pi + a GPS cap on the RPi + decent webcam + OpenMaps (you don't even need this unless you want to plot it); Maybe add a condition to send plate location over $XXXX to some traffic enforcement distros. Hardware for a setup will probably run $250 tops if you're going fancy
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