5 ms·

OpenALPR: Automatic License Plate Recognition Library

44 points by trymas 11y ago

awjr 11y ago
There is a slight issue with this library in that it is "gimped" to one CPU. You can licence a multi-cpu version http://www.openalpr.com/ http://www.openalpr.com/ but the open source one would be a lot cooler.
- nitrogen 11y ago
  The license says its AGPLv3. Is there an additional restriction somewhere that prevents one from modifying the code to run on multiple CPUs?
  - Natanael_L 11y ago
    No GPL version allows adding such restrictions.
deleted 11y ago
[deleted]
dzhiurgis 11y ago
What is the best way to integrate this with a camera? Is there any specific IPTV cam platform?
- lhaussknecht 11y ago
  Most cameras offer a HTTP interface to acquire images. You can feed those to the LPR. Some LPR stacks offer recognition of license plates directly from video streams (MJPG, H.264).
jmnicolas 11y ago
> -c <country_code>, --country <country_code> Country code to identify (either us for USA or eu for Europe). Default=us Europe is not a country, it's a continent with multiples countries, each one with its own scheme for creating license plates. Can't test it right now, but if you look for a Swiss, Belgian and French (old and new) license plate you'll see they have nothing in common.
- unwind 11y ago
  That's just ... weird. I wonder how the developers, who reasonably have spent quite a while looking at and thinking about license plates, can make such an error. It would of course have helped if they had provided more documentation regarding what the software considers to be the differences between US and European plates that makes it able to cope with all of Europe as a single mode, but not with US' plates.
  - atomwaffel 11y ago
    From what they write in their live demo[1], it's about the dimensions of the plate rather than what's on them: > OpenALPR supports both North American style (12 inches by 6 inches) and European style (52 cm by 11 cm) license plates. That makes a bit more sense. Then again, the "Country" field there gives a choice of North American, European, Australia, Great Britain, Singapore, Korea. I wonder if accuracy couldn't be improved quite a bit if they included heuristics for individual countries. For instance, German licence plates should be really easy to read thanks to their "forgery-impeding typeface"[2] which has uniquely distinctive features for each letter. It's also not guaranteed that all European licence plates have those dimensions. Motorcycles and tractors for instance have taller, narrower plates, and cars where regular plates wouldn't fit (like imported or antique cars) can get special plates as well. And then of course there's Switzerland which has wildly different dimensions and has changed its mind every few years[3]. [1] http://www.openalpr.com/demo-image.html http://www.openalpr.com/demo-image.html [2] https://en.wikipedia.org/wiki/FE-Schrift https://en.wikipedia.org/wiki/FE-Schrift [3] https://en.wikipedia.org/wiki/Vehicle_registration_plates_of_Switzerland https://en.wikipedia.org/wiki/Vehicle_registration_plates_of...
- robzyb 11y ago
  "The common EU format of having a blue section on the extreme left with EU circle of stars and the country code was introduced by Council Regulation (EC) No 2411/98 of 3 November 1998[1] and entered into force on the 11 November 1998." https://en.wikipedia.org/wiki/Vehicle_registration_plates_of_the_European_Union https://en.wikipedia.org/wiki/Vehicle_registration_plates_of... Maybe not all countries adopt the EU standard, but it makes sense that there is an "eu" mode.
TeeWEE 11y ago
How does this work internally. Its not using a neural net is it?
breakingcups 11y ago
It missed a G on my test image. A very interesting project nonetheless.

44 points by trymas 11y ago

awjr 11y ago

There is a slight issue with this library in that it is "gimped" to one CPU. You can licence a multi-cpu version http://www.openalpr.com/ http://www.openalpr.com/ but the open source one would be a lot cooler.

nitrogen 11y ago
The license says its AGPLv3. Is there an additional restriction somewhere that prevents one from modifying the code to run on multiple CPUs?
- Natanael_L 11y ago
  No GPL version allows adding such restrictions.

deleted 11y ago

[deleted]

dzhiurgis 11y ago

What is the best way to integrate this with a camera? Is there any specific IPTV cam platform?

lhaussknecht 11y ago
Most cameras offer a HTTP interface to acquire images. You can feed those to the LPR. Some LPR stacks offer recognition of license plates directly from video streams (MJPG, H.264).

jmnicolas 11y ago

> -c <country_code>, --country <country_code> Country code to identify (either us for USA or eu for Europe). Default=us Europe is not a country, it's a continent with multiples countries, each one with its own scheme for creating license plates. Can't test it right now, but if you look for a Swiss, Belgian and French (old and new) license plate you'll see they have nothing in common.

unwind 11y ago
That's just ... weird. I wonder how the developers, who reasonably have spent quite a while looking at and thinking about license plates, can make such an error. It would of course have helped if they had provided more documentation regarding what the software considers to be the differences between US and European plates that makes it able to cope with all of Europe as a single mode, but not with US' plates.
- atomwaffel 11y ago
  From what they write in their live demo[1], it's about the dimensions of the plate rather than what's on them: > OpenALPR supports both North American style (12 inches by 6 inches) and European style (52 cm by 11 cm) license plates. That makes a bit more sense. Then again, the "Country" field there gives a choice of North American, European, Australia, Great Britain, Singapore, Korea. I wonder if accuracy couldn't be improved quite a bit if they included heuristics for individual countries. For instance, German licence plates should be really easy to read thanks to their "forgery-impeding typeface"[2] which has uniquely distinctive features for each letter. It's also not guaranteed that all European licence plates have those dimensions. Motorcycles and tractors for instance have taller, narrower plates, and cars where regular plates wouldn't fit (like imported or antique cars) can get special plates as well. And then of course there's Switzerland which has wildly different dimensions and has changed its mind every few years[3]. [1] http://www.openalpr.com/demo-image.html http://www.openalpr.com/demo-image.html [2] https://en.wikipedia.org/wiki/FE-Schrift https://en.wikipedia.org/wiki/FE-Schrift [3] https://en.wikipedia.org/wiki/Vehicle_registration_plates_of_Switzerland https://en.wikipedia.org/wiki/Vehicle_registration_plates_of...
robzyb 11y ago
"The common EU format of having a blue section on the extreme left with EU circle of stars and the country code was introduced by Council Regulation (EC) No 2411/98 of 3 November 1998[1] and entered into force on the 11 November 1998." https://en.wikipedia.org/wiki/Vehicle_registration_plates_of_the_European_Union https://en.wikipedia.org/wiki/Vehicle_registration_plates_of... Maybe not all countries adopt the EU standard, but it makes sense that there is an "eu" mode.

TeeWEE 11y ago

How does this work internally. Its not using a neural net is it?

breakingcups 11y ago

It missed a G on my test image. A very interesting project nonetheless.