DRIVE-by spy cameras set for trial in Victoria could triple the number of parking fines issued to motorists.

The digital technology allows parking officers to automatically detect offences simply by driving past.

The "autoChalk" system combines global positioning, lasers and cameras to record the shape, colour and registration details of every car parked along a street.

It remembers how long a car has been in one spot and fines over-stayers on the next drive-by.

The hi-tech system will replace traditional "grey ghosts" who patrol suburban streets on foot, marking tyres with chalk.

The machine can scan more than 7000 cars an hour.

The system records before and after images of offending cars in case of a challenge.

Victorian parking enforcement company Tenix Solutions said it had started testing autoChalk.

A two-month trial is planned and the system could be rolled out for councils by June.

The system's Canadian inventor boasts the technology triples the productivity of parking inspectors.

Councils overseas have tailored the system to issue higher fines to repeat offenders.

Tenix Solutions product manager Sally Damiani said autoChalk would stop motorists hogging timed spaces.

Concerns have been raised overseas about the system recording false positives - where a car resembling one parked in the same spot earlier is fined.