Low Cost License Plate Capture Shootout

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Derek Ward
Published May 21, 2014 04:00 AM

******* ***** ******* (***) ** **** popular ** ***** ** *** ******* ***** ******* ******** ****'* **** ****** ********. 

*** ********* ** *********** ***** *** ******* *** *** quite *********, **** ** *********** ***, like ************ ** *** ** ******, **** ~$*,***.

** ******* ** **** * *** cost ********** ** ** *******, *** $200 ** ****, ********* *****, ********* and *-*** ******, ** *** ** **** could ******* ********* ******* ***** *******.

** ****** ** **** ***** (~****) and ****** ***** (~*****), *** *** night, **** **:

*** ** ******* ***** *********** *** each ** *** ** **** (********* various ******* ******), **** **** **** so:

************

*** ********** ** *********** ****** ** capturing ******* ******, ***:

Key ********

**** *** *** *** ******** **** this ****:

  • ***** ******* ********, *** ******* **** able ** ******* ****** ** **** (~5 ***) *** **** (~** ***) speeds ****** *** ***.
  • ** ******* **** **** ** ******* plates ***** ******* ******** ** ****** speed ** *****.
  • ***** *** **** ************ ******** ** these ***** **** ********** ** *******, overexposure ** *** ****** ********** ***** was * *******, ********* ****** ******** speeds *** ******** *******, ************* ********* the ******* *****.
  • ***** *** **** ******** ** *** cost ********** ** ******* *** ***** lenses, ******** ********* *** ** ***** the ******** ********, **** *****, ***., may ** ***********, ******** ***********.
  • ***** *** *** **** ******* ******, the ********* **-*******-* ****** ********* **** at **** **** *** **** ****** due ** * **** **** ************ pattern, ********* ****** ** ******* ****** as *** ** */****. ***** ******* required */***** *** ** *** ******** capture.
  • *** *-*** ******** ********* ***** ** *** tests *** ** * **** ****** IR ******* ******* ************ ** ******, requiring */*,**** ******* ***** *** ******** capture ** ~* ***, *** ******* to ******* ****** ** ~** *** even ** */**,***********.

*******

*********** ****** ******* ** ** *******:

***************

*** *** ***** ******* ***** *******, these *** **** ********** ** ******* may ****, **** ************* ****** ******* ****** than*******. ***** ***** *** *****, ********** two ******* (***** *** *** ******* and *** ******** ******** ***** ******* ********) ** possible *** **** **** *** **** of *** ********* *********** ******* ***** capture ****** (~$*** *** **).

*** ****** ***** ******* ***** *******, 30 *** *** **, **** *** work, *** ** ******* *** ***** will ****** ** ****** ****** **** at ****** ******. *********** ****** ** ******** in *** ***** ****** ******* ** **** for *******.

IR ************ ********

*** ** *** *** *************** *** low **** ** ******* *** ***** ability ** ************ ******* * ******* plate ** ***** ** ************ ********. Cameras **** ******** ** *** ****** of *** *** *** ****** ** patterns require ****** ******* ****** ** ********** for * ******* *********** *****.

*** *******, ***** ** * ********** image ** ************ **-*******-** *** ************ **-*******-*. ******** ** *** **** **** our**** ********* ** ****** ****, **'* *** ** *** ****** but *** ****** ** ***, *** less *****.

Slow ***** *********** (

** **** ****** *** ******* *********** at **** ******, ~*-** *** ** a commercial parking ***. ******* **** *** ** capture *** *****, ** * ~**' HFOV.

***** ** *** ******* *** **** the ******* ***** ******** ** **** camera ** ******* ******** **** * 1/30 *** ******* *****. ** **** in *** ****** ******* *******, *** cameras *** **** ** ******* *** plate ** *** **** ***.

*****

** ****** ** **** **** *** at *****, ** ****:

*/** ******* *****

******* ** *** ****** *****, ******* are ****** ** ******* * ******* plate ** * ****** *** **** at ~* *** **** * */** second ******* *****, *** ** ****** **** and ************ ** ** ************ ** *** plate.

*/*** ******* *****

** */*** ****** ******* *****, ** get * ***** ***** ** *** license ***** **** *** ********* **-*******-* ** this *****. *** ****** *** **** to **** ********* **** ***** ********** or *** ****** *** *** ****************.

*/*,*** ******* *****

**** */*,*** ******* ******, **** ******** *** Dahua *** ******* *** *****, ******* to *** ****** *******.

*/*,*** ******* *****

** */*,*** ******* ******, *** *-*** and ********* **-*******-** *** **** ** get * ***** **** ** *** plate **** *** **** *** ** traveling ~* *** ** *** ******* lot ********.

High ***** ***********

** ***** ****** ******* ***********, **** *** test ******* ********** ***** ** ***. The * ******* **** **** ** default ********, **** * */** *** shutter *****. *** ******* **** **** to ************ ******* *** *** **** minimal ****** **** ** **** ** grab * ***** ***** ** *** license *****.

Nighttime ***********

** *****, *** *** ****** ******** at ~******** ** ** ******** *********** ******** above *** *******. ***** ** *** general *** **** *** *******. *** cameras **** **** ** ******* ********, with *********** ***** **** *********** ** shutter ******.

*/** ******* *****

******** ** *** ******** **** *** daytime *******, ** *** ******* *** that ** ****** *** ** *** 5 ** **** *** ******* *** able ** *** * ***** ** off *** ******* *****.

*/*** ******* *****

******** ** *** ******* ** */*** seconds, *** ******* ***** ******* **** washed *** *** ******. *****, ** camera ** **** ** ******* * clear ******* *****.

*/*** ******* *****

** * */*** ****** ******* *****, the ******** *** ********* ****-* *** able ** ******* * ********* ******* plate, ***** *** *****,*************-** *** *-*** *** ***** ************* blurry *** ****** ***.

*/*** ******* ***** (********* ******* ****).

***** ******* *** *** **** ******* ******* speed, ** *** ***** **** **** Hikvision ******* *** */*** ******* ******, which *** * ***** ** ***** camera ****** *** *********. ** **** speed, *** ********* **-*******-* ******** * plate *******, ***** *** ****-** ***** not.

*/**** ******* *****

** */*,*** ******* ******* ******, *** Avigilon ** **** ** *** * clear **** ** *** ***** ** this *****, *** ******** ***** ******** * ****** *****, **** some ********** *******.

*/**** ******* *****

******* ****** */*,***, *********** ********* ****-** *** ***** ***** of *** ******* *****. *******, *** Q-See **** *** **** ***** ** capturing * *****.

*-*** ***** ** *******

** ******* ****** ** */*,*** *** 1/10,000 *** ******, *** *-*** ******** is ********* ** ********* * ******* plate ** * ~** *** ****** car ** *****.

Video ********

*** ********* *** ******** ** ********* plate ******* **** *** ******* ** varying ********.

** **** *****, ** **** ******** all ** *** ********** ****** ** each ****** ** *** ******* *** scene. **** **** *** ******* ** traveling ~* *** ** * ~* lux *****.

** **** *******, ** **** ******* of **** ****** **** *** **** to ******* *** ******* ***** ** their ******* ******* ****** *** **** test. ******* *** ***** ** ************ order.

** **** ****** ****, ** **** compiled **** **** **** *** *-*** 7001B ** ***** *********** ******* *****. Users **** ****** **** *** *-*** was ****** ** ******* * ******* plate ** *** ******* *****.

***********

******* **** ****** ***** ******* ******** at ** ***, ****** ********* *****. All cameras ******* ** */*** ******* *****, which *** **** ***** *********. ******* were ****** *** ** * **** so ** ************ ************ *** *** an *****, **** *** ******* ****** past ** *** ********* ***** ******** times ** ***** *******.

******* **** ********** ** *********** ******* 6.0.10.59050 without *****. *** ********* ******** ******** were ****:

  • ******** *.**-**-***-**: *.*.*.**
  • ***** ***-*********: *.***.****.*.*, ***** : ****-**-**
  • ********* **-*******-*: **.*.* ***** ******
  • ******** **-*******-**: **.*.* ***** ******
  • *-*** ********: *.***.****.*.*, ***** : ****-**-**
Comments (17)
Avatar
John Bazyk
May 21, 2014
Command Corporation • IPVMU Certified

This is a great post, thanks. One of my customers was asking about a LPC Camera the other day, he already has a Hikvision 2232 installed looking at the entrance of the parking lot. We can read plates easily during the day but not at night, going to test this out and see how it works.

BG
Bob Germain
May 21, 2014

John- you may want to test the 2232 with and without Smart IR enabled. it is disabled by default which may be why the reflection issues in this report.

Derek- nice report.

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Luis Carmona
May 21, 2014
Geutebruck USA • IPVMU Certified

The right tool for the right job. Real tag cameras for tag shots.

BP
Brad Pyles
May 22, 2014

The solution is to use an IR pass filter and more IR illumination to capture a B&W image 24/7...We have beeen doing this for years. IR pass filters need to match the IR Illumination and are available from any photo supply store. The only problem we see is direct sunlight can flood the scene so North -South view is best.

JD
Jim Daly
May 23, 2014

Hi Brad,

Can you expand on this point please?

Thanking you,

Jim

JH
John Honovich
May 24, 2014
IPVM

An IR pass filter will block 'colored' light. Once you put the filter on, it's on 24/7/365 and does not switch or cut back and forth (unless someone manually removes it).

They look like so:

You'll typically need a box camera that allows adding on filters.

During the day, the downside, is that you lose color.

At night, the upside, is that the visible / color light is filtered, i.e., does not reach the lens. This cuts down on glare from headlights, in particular. The problem we found in our headlights test is that headlights produce a lot of IR light as well, and that will still pass. Because of that, we found that added IR light next to the camera (or integrated inside) was still important.

RW
Rukmini Wilson
May 24, 2014

You'll typically need a box camera that allows adding on filters.

During the day, the downside, is that you lose color.

Any other downsides? Because if that is the only one they should just make a combo IR cut/pass mechanical filter. Maybe one is you still lose 'color' at night, even though you don't see it as color. But wouldn't it make the image darker?

BP
Brad Pyles
May 25, 2014

Did I forget to mention the RayTec IR units... We flood the scene with IR

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Marty Major
May 22, 2014
Teledyne FLIR

Good report Derek...

I'm curious about your use of the term 'capture' vs 'see'.

In most LPR applications, isn't it the LPR software used in conjunction with the camera that does the capturing (identifying the number/letter pattern as a license plate, then comparing the 'hit' to an active database), while the camera simply sees what it can see?

I think it would be interesting to see how some of the LPR software player's stuff would perform using the cameras and lighting conditions from your testing...

Any plans on an LPR software shootout?

JH
John Honovich
May 23, 2014
IPVM

See: License Plate Capture Vs Recognition: LPC Vs LPR.

I think an LPR test would be interesting but that's going to be more logistically challenging to coordinate as those are typically not simply available online for us to purchase. However, given the positive response to the LPC tests, it's worth us looking into.

LS
Louis Sun
May 27, 2014

thanks IPVM, you are doing really great testing!

JH
Jerome Humery
Jun 30, 2014

Maybe I missed it, but at what distance did you set-up the cameras for this test?

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Derek Ward
Jun 30, 2014
Hanwha

Jerome,

The cameras were placed ~3' away from where the car was passing (on a sidewalk, for example), and the passing license plates were captured ~5-7' away (When the license plate could be seen on camera).

JD
Jim Daly
Jul 08, 2014

Dahua Licence plate camera with OCR on-board

Just got an email about this unit from Dahua, it was not on show at IFSEC London to my knowledge. link automatic-license-plate-recognition camera

JH
John Honovich
Jul 08, 2014
IPVM

Jim, good find!

We'll try to find out if and when it will be available. Information looks very limited online which may mean that it's not available outside China now.

JL
Joe LoRe
Dec 10, 2017

Just installed 2 hikvision ds-2cd4a26fwd-izh/p connected to a new 7608ni-i2/16p fw V3.4.93 First time using these(afterall they just showed up in the most recent catalog a month or 2 ago).  Cameras are 8ft above ground on a poll curbside and lenses are set to 12mm and running 30fps which is only half of its capable frame rate.  Seems to be having a hard time reading plates, picture wise i can see plates fine but cameras/NVR not picking them up properly, only once in a while does it properly read plate. I took Hikvision suggestions as far as mounting height, angle oppsed to target, and increasing shutter speed.  Any ideas?

Thanks

 

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David Delepine
Dec 11, 2017
Brivo • IPVMU Certified

May need to play with gain/iris/ir settings depending on illumination. Recently used some Dahua (12mp motorized zoom and the lesser 6mp versions and was able to catch plates at +/- 20mph at 60-100ft. However default settings need to be customized to 1/250 shutter speed and depending on front/back plate desired affects IR/gain/iris/etc need to be tweaked. I am  from an expert at this particular application but just wanted to share my experience. Hope this helps!