Intrada Synergy

Intrada Synergy delivers automatic, high-performance image handling of images, which reduces the operational cost associated with Automatic License Plate Recognition (ALPR) for enforcement and tolling/Road User Charging (RUC) applications.

Intrada® Synergy is scalable from a single, tuned Intrada ALPR library up to an integrated set of video processing modules. Guaranteed customer-specified levels of identification performance in automated image-handling applications result in workflows that are optimised for domain, the camera systems used and any vehicle properties.

Intrada Synergy uses a series of modules which employ ALPR, vehicle recognition and manual review. Rules-based working and tailoring ensure that customers’ systems performance meets agreed performance levels and maximise operational efficiencies.

Unmatched recognition performance is allied to ease of integration and deployment through standardised network-based interfaces, and extensive statistical and health-reporting functions.

With its unmatched image processing capabilities Intrada ALPR can deliver guaranteed performance in terms of both high yield and diminishable error rates, as demonstrated by currently deployed systems. In the solution we at Q-Free supplied for the Stockholm congestion tax charging scheme, for instance, Intrada automatically handles 97 percent of the images with an error rate of less than 0.01 per cent. For the Amsterdam Low Emission Zone, Q-Free ALPR products achieve a 98 per cent read rate with an error rate which is below 0.1 per cent, and OEMs in the traffic management and access control sectors who run Q-Free Intrada ALPR within their own products manage to automatically identify close to 100 percent of passing vehicles.

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When delivering Intrada Synergy, our significant experience of previous deployments enables us to ensure customer-specified levels of identification performance in automated image-handling applications. This results in workflows that are optimized for the domain, the camera and any vehicle properties.


Intrada Synergy Modules

  • Intrada ALPR: Automatically reads license plate numbers from still images.
  • Intrada VSR: Identifies vehicles without actually reading the characters on the license plate. Instead, pictures are matched to a previous observation. This allows automatic identification of vehicles even when the registration number could not be read through ALPR, typical examples being special plates not designed for ALPR or fixed objects partially occluding the license plate.
  • Manual Review: Despite the very high performance levels of the ALPR systems provided by Q-Free, there may still be a need for manual review of images. Therefore, we can also provide the infrastructure and user interfaces needed for most efficient handling of manual image inspection in the project at hand.

Maintaining deliveries to ensure continuously meeting the agreed performance

  • Business Rules: A workflow that prescribes the integrated use of the previous three elements. Such business rules specify what would be the registration number given the ALPR result from the front and rear cameras, and when to delegate to VSR or Manual Review.
  • Tuning: Tailoring and maintaining of the aforementioned to ensure that the agreed performance levels are continuously met.

How these five modules fit together is shown in the diagram. The input (front and/or rear) images are fed into the Intrada Synergy workflow. The Business Rules (center) prescribe when to apply Intrada ALPR, Intrada VSR and Manual Review. The registration codes are returned as output according to the local department of motor vehicles’s format.


  • Q-Free’s deep knowledge and wide experience of automated image-handling packaged into one self-contained identification module
  • Unmatched recognition performance (possible yield of over 98 percent with negligible error rate – less than 0.01 percent)
  • Can be integrated as a software component within any image handling back office
  • Optionally integrated Manual Review clients for manual verification
  • Ease of deployment and integration realized by standardized network-based interfaces, such as Web services and network shares
  • Extensive statistical and health reporting functions which help to ensure high availability and continuous yield
  • High scalability and reliability through dynamic assignment of unlimited processing capacity


Integration and deployment

From a technical point of view, a delivery of Intrada Synergy consists of software modules and configuration files with a pre-defined software interface, as well as user interfaces for manual review (when applicable) and a formal description of the business rules.

You can use your own workflow management system to implement the business rules and to call upon the various video processing modules as applicable. In addition we can advise on the implementation within your organization, for instance how to arrange storage and transport of images.


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