Milestone LPR 1.0 - Manual (Page 18)

Milestone XProtect
®
LPR 1.0 Administrator's Manual
www.milestonesys.com 18 LPR servers, sources and lists
By tuning the settings on the Processing tab, a trade-off between processing speed and recognition
quality can be defined. Thus the recognition process halts if any of the stop criteria are met.
Furthermore, limiting the processing frame rate allows using a higher frame rate on the camera without
adding an unnecessary load to the LPR server.

Use at most: Enables the usage of milliseconds per frame (number of milliseconds per frame
allowed to be spent on the recognition of one image) as a stop criterion. Default setting is
disabled. If enabled, default value is 0. If adjusted, recommended value is 200 ms per frame.

Stop processing license plate when: Enables a minimum confidence level (in percent) as a
stop criterion. Default setting is enabled and default value is 80%. Change the default value if
needed. The recognition process continues until the system is at least 80% sure of the identity
of a license plate.

Detect at most: Enables maximum number of license plates returned per frame as a stop
criterion. Default setting is enabled and default value is 1. Change the default value if needed.
Tip: Increase the Detect at most default value if, for example, you are detecting multiple lanes
with the same LPR camera.

Reject license plates below: Enables a minimum confidence level (in percent) as a stop
criterion. Default setting is disabled. Also, specify the minimum value in percent. The system
rejects license plates where the confidence level is equal to or lower than the specified value.

Limit processing to: Enables a limit to the amount of frames being processed per second
(FPS). Default setting is enabled and default value is 4 FPS. If you limit FPS, the system can
use a higher FPS on the camera for recording without adding unnecessary load to the LPR
Server.

Interlaced: For best performance, select this with interlace cameras.
Whenever one of the above stopping criteria is met, the recognition process stops and returns the
answer found so far.
List tab
Here you select which license plate list(s) a specific LPR camera should match license plates against.
You can create as many lists as needed (see "Add new license plate list" on page 21).

All: License plates are matched against all available lists.

Selected: Choose one or more of the available lists. License plates are matched against
selected lists.
Tip: Events are only generated for selected lists.
When you are done specifying settings for your LPR system, test your setup (see "Test current LPR
configuration" on page 19) in live view to see if it recognizes license plates as expected.
Countries tab
Here you select which license plate libraries this specific LPR camera should use. What you can select
from, depends on which libraries you have installed (see "Install XProtect LPR" on page 10) and your
license situation (see "LPR Licenses" on page 6).