How to automate license plate redaction in video footage

If you regularly handle CCTV, bodycam, dashcam, retail car park, or traffic footage, automated redaction is usually the only practical way to redact number plates without relying on frame-by-frame manual editing or outsourcing footage.

Keep reading to learn about different approaches to video redaction automations and get practical tips for a smooth process.

#When organisations need to redact license plates

Teams at organisations that record footage of parking lots, streets, or any other environment where vehicles and their license plates are captured on CCTV or bodycams will need to redact videos when:

• Sharing footage with third parties (insurers, legal teams, media, contractors, partner organisations). Plates that are unrelated to the incident usually need to be masked.

• Processing subject access requests (SARs). When disclosing video footage, you typically need to protect the personal data of third parties that commonly includes faces and vehicle number plates.

#How automated license plate redaction works

Automated video redaction is a workflow where the software:

• Detects plates in the frames you select

• Tracks them through motion, occlusion, and/or camera movement

• Applies a consistent mask that can be adjusted based on the video quality

• Lets you review the redacted video quickly and finalise it without starting all over again

That last point matters. Even strong detection will miss the occasional number plate in low light, tight angles, or busy footage. You want software tools that don’t force you to restart redaction whenever you make a change.

#Ways to automate license plate blurring (and where each one fits)

#1) Dedicated redaction software

Dedicated tools are built to make it easier to process videos without going through footage frame-by-frame. Teams import footage, redact, review, and export a redacted clip, while keeping the original unchanged.

This is the most common route for councils, transport operators, retail, and other organisations handling a growing number of video requests.

#2) VMS plug-ins 

A plug-in can keep your workflow inside your VMS instead of exporting clips and re-importing them elsewhere. Facit provides Milestone plug-ins for both live masking and playback redaction.

#3) API integration (best for high-volume pipelines)

If you have an application that already ingests video (for example, an evidence management system), an API can push redaction into your existing pipeline. Facit offers API integration options — contact us to discuss deployment.

#Step-by-step: automate number plate redaction with Identity Cloak

1) Import your footage
Identity Cloak supports MP4 and AVI. If your footage is in a proprietary player format, you can use the built-in screen recorder to import it without file converters.

2) Trim the video to the relevant segment

If you only need a 90-second window, don’t process a 45-minute recording. Trimming the video reduces review time and reduces the risk of disclosing personal data. You can also crop the video to only focus on the relevant part of the screen.

3) Turn on license plate blurring

Identity Cloak will automatically blur out number plates throughout the video footage. You can also adjust tracking settings to redact plates on fast-moving vehicles.

4) Review the footage

Do a play-through to catch obvious misses, then use frame-by-frame review around key moments: close passes, zoom changes, or people moving in front of vehicles.

5) Export the redacted file

Export in MP4 or AVI for sharing. Identity Cloak leaves the original file unchanged, and the exported redaction is irreversible.

“Facit saves us time. A 1-minute video takes 8 minutes to process. That’s start-to-finish – uploading the video, processing and exporting.”
Geoff Shepherd CCTV Supervisor, Nottingham City Transport

If you want a walkthrough of the workflow for face blurring, see this post on blurring faces in video footage.

#Practical tips for better automated plate redaction

#Check for challenging scenarios

Make sure you check parts of the clip that may trip up automated redaction:

• low lighting videos or low-quality footage clips,

• people crossing in front of cars or vehicles overlapping,

• partially concealed vehicles or signage obscuring moving vehicles, and so on.

“It’s made an unbelievable difference - like night and day. Even in complex scenes, Identity Cloak finds and redacts the vast majority of sensitive material automatically and minimises the need for manual intervention.”

Paul Whelan, Data Protection Officer (DPO) at CIÉ

#Trim before redaction

Trimming is one of the simplest ways to reduce redaction and review time, as well as privacy risks.

#Consider if additional blurring is necessary

In addition to blurring license plates, you may want to determine internally if you also need to anonymise vehicle make and model. This may be useful if you’re handling recordings of a specific carpool (Identity Cloak blurs license plates, models and brands by default).

Get a full list of our tips for choosing the best video redaction software for your organisation’s needs in this guide.

#Data protection and compliance notes for Identity Cloak

Identity Cloak is available as Milestone plug-ins for XProtect and as a desktop version.

Our desktop software:

• Works on-premise: Identity Cloak is installed on your device within your secure network. Facit does not transfer videos to its servers.

• Original remains intact: the original file is left unchanged for integrity, and the redacted export is a separate, irreversible file.

Operates behind a firewall: Identity Cloak can operate behind a firewall and can be fully air-gapped.

#Evaluation template for license plate redaction software

If you’re comparing tools, these are the points that tend to decide whether the software works in day-to-day operations:

• Tracking quality for fast-motion, low-light, and low-quality videos

• Control over tracking behaviour (speed/keyframes)

• Workflow fit: standalone app vs VMS plug-in vs API

Deployment requirements: on-premise installation vs cloud software, hardware requirements for on-premise tools, ability to work behind firewall and air-gapped

#Try license plate redaction with Identity Cloak

Start a free 7-day trial of Identity Cloak to try out automated license plate redaction on your own footage. If your workflow is centred on Milestone XProtect, consider going with Identity Cloak plug-ins for Milestone.