nayr
IPCT Contributor
nayr
IPCT Contributor
OpenALPR scans the video feed (MJPEG format only unfortunately) in that mask for a rectangular high contrast object it believes may be a license plate, when it finds one it does some more quick analysis to make sure its really a plate, then it saves the image and runs some text recognition software on it to attempt to read it.. in the end it spits out a couple jpegs and a couple text files full of its best guesses at readings every time a car with a visible plate passes by my camera..
I can search through the text files to find matching images if someone reports a partial plate number on nextdoor.. or I can just browse through the all the images durring a specific time window and see what vehicles it identified.
Once I have my raspipc project released, I am going to whip up a fancy web interface for managing all the data the LPR camera gathers.. like grouping cars together and using some big-data strategies on analyzing all the information.. giving me stats on number of cars per day, number of hits per car, etc.
since late may til now I have gathered 204GB of license plate data..
I can search through the text files to find matching images if someone reports a partial plate number on nextdoor.. or I can just browse through the all the images durring a specific time window and see what vehicles it identified.
Once I have my raspipc project released, I am going to whip up a fancy web interface for managing all the data the LPR camera gathers.. like grouping cars together and using some big-data strategies on analyzing all the information.. giving me stats on number of cars per day, number of hits per car, etc.
since late may til now I have gathered 204GB of license plate data..
bigbadw
Getting the hang of it
- Sep 16, 2014
- 203
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Wow! That is just too cool. I went down a different path and simply tried to do License Plate Capture. This does force me to look for car pictures/videos during a specific timescale, then zoom in on the captured image/video to personally read the plates. We have helped bust two burglaries in the neighborhood with this method. I wasn't aware of your approach, but am sure going to look into it!
Nayr has his Alpr software set up to crop the image for processing, not the camera or BI.
If your cam has 'target cropping', (Configuration> Advanced Configuration> Video/Audio> Target Cropping), that will
show the cropped portion of the full image in the THIRD stream, apparently (not the main stream.)
If your cam has an ROI tab (aRea Of Interest, go figure... under Video/Audio settings,) that can allow you to configure an area that maintains higher resolution (less compression) than the rest of the image, which might be an option to optimize the area of the full image that is most likely to have plates in it.
as for " I can select different exposures, but there is no SAVE feature enabled on that page", make sure you use Internet Explorer browser,
as some configuration aspects just don't work right on other browsers. sad but true. If you're already using IE, maybe post a screen shot
of that page? fwiw, i have my (Huisun) LP cams set at 1/1000, but that acts as a MAXIMUM exposure in that the cam auto-adjusts exposure to
shorter lengths of time as needed during the day, but won.t go longer then that at night. That's why I can get plates at night with a ton of IR but not see anything other
than plates and head/taillight... Basically, if you find a setting that works at night, the same setting will most likely work in the daytime
unless your cam is retarded like the LongSe's are, but your Hik should be fine...
If your cam has 'target cropping', (Configuration> Advanced Configuration> Video/Audio> Target Cropping), that will
show the cropped portion of the full image in the THIRD stream, apparently (not the main stream.)
If your cam has an ROI tab (aRea Of Interest, go figure... under Video/Audio settings,) that can allow you to configure an area that maintains higher resolution (less compression) than the rest of the image, which might be an option to optimize the area of the full image that is most likely to have plates in it.
as for " I can select different exposures, but there is no SAVE feature enabled on that page", make sure you use Internet Explorer browser,
as some configuration aspects just don't work right on other browsers. sad but true. If you're already using IE, maybe post a screen shot
of that page? fwiw, i have my (Huisun) LP cams set at 1/1000, but that acts as a MAXIMUM exposure in that the cam auto-adjusts exposure to
shorter lengths of time as needed during the day, but won.t go longer then that at night. That's why I can get plates at night with a ton of IR but not see anything other
than plates and head/taillight... Basically, if you find a setting that works at night, the same setting will most likely work in the daytime
unless your cam is retarded like the LongSe's are, but your Hik should be fine...
nayr
IPCT Contributor
I also have it updating the camera's on screen text when it reads a plate..
I record this camera in 720p, so thats the quality you get.. but the analysis is done on a 4MP MJPEG feed thats far too massive to save.. the resulting jpeg files are all 4mp resolution and thats what I want.
I record this camera in 720p, so thats the quality you get.. but the analysis is done on a 4MP MJPEG feed thats far too massive to save.. the resulting jpeg files are all 4mp resolution and thats what I want.
bigbadw
Getting the hang of it
- Sep 16, 2014
- 203
- 42
Pozello, thank you for the response. I definitely have tried both IE and recently tried Chrome. I added a couple of screen shots showing that it is set on 1/1000 for night exposure, then I select 1/500 but there is no "save" option displayed below. On every other option change, such as "start time" or "end time", it shows a save button below.
nayr recommended resetting the camera to factory defaults and see if that frees the "save" button from a different setting that could be disabling that somewhere. My physical configuration makes that a bit of a chore, but I am thinking that is my only choice!
nayr recommended resetting the camera to factory defaults and see if that frees the "save" button from a different setting that could be disabling that somewhere. My physical configuration makes that a bit of a chore, but I am thinking that is my only choice!
Attachments
I always read ROI as "Region Of Interest". I believe that option is available on my Dahua, but I hadn't experimented with it. Now I'm curious so I'll try it out.
bigbadw
Getting the hang of it
- Sep 16, 2014
- 203
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Ok, the first experiment starts this evening. I hooked the new IR Illuminator is now taped on top of my License Plate Capture camera. The camera is still set at 1/1000 (vs 1/500), and the frame capture is a larger than it needs to be.
I need to wait for my standalone POE switch to arrive, so that I can log in and modify the existing cameras settings.
I need to wait for my standalone POE switch to arrive, so that I can log in and modify the existing cameras settings.
nayr
IPCT Contributor
you need to get you a test plate; get on like ebay and buy a modern license plate from your region.. consider your locality; back in Kansas they made everyone get new plates every decade or so; thus everyone had new highly reflective plates.. Here in Colorado they let you run anything for the life of the vehicle.. so I have some 30 year old cars that are a bitch trying to read the original beatup plate on... Me I have a handfull of plates from new to old to test with, you might just need a new plate.. infact I ran 1/1000 for a while until I had a few older or very dirty plates it could not see, 1/500 seemed to be better and I could run less gain so the image had less noise and that really helped OpenALPR as noise is what fucks with it the most.
I have a little rig I go setup on the sidewalk so I can play with exposure settings, focus, etc without waiting for traffic at night; which is too slow for me in a metro area.. but you can also just hold it and do walk tests too, gets you some exercise.
or you can wait til very late at night and just go park your car there and hope no drunks drive into it
I have a little rig I go setup on the sidewalk so I can play with exposure settings, focus, etc without waiting for traffic at night; which is too slow for me in a metro area.. but you can also just hold it and do walk tests too, gets you some exercise.
or you can wait til very late at night and just go park your car there and hope no drunks drive into it
I've got a start with a script to run OpenALPR on a directory full of .mp4 clips and select the highest-confidence reading from each clip. I've learned a few things: if the field of view can include a closer parked car, that plate generally is the most readable, so I need to work with multiple plates per scene. I was puzzled by a plate coming up SPLUL. Had a look and saw a truck, the actual plate was smaller and shadowed underneath but the mud flap was marked in bold letters: ASPLUNDH (2nd half blocked by the trailer).
bigbadw
Getting the hang of it
- Sep 16, 2014
- 203
- 42
Thought I'd pass on a "slightly related" technical issue that FINALLY got resolved....
My Hikvision camera that is dedicated to capturing license plates would not allow me to make any configuration changes. I won't go into the months I spent researching and trying different options. I called Hikvison tech support. They did not want to help since most of my cameras were purchased on Amazon, Newegg or from China. Luckily a couple were able to get me through to tech support, BUT, they wanted to make sure the firmware version was updated before they would proceed. The camera would not allow me even upload a new firmware.
So, what was the problem?
After all this time, it turns out... MS Edge is not Internet Explorer. Yup... I was using the stupid E on the taskbar (which turns out to be Edge)... Once I ran I.E., the config files were modifiable...
Tonight I find out if changing night capture to 1/500 improves the License Plate image quality. Also, I set the ROI to only the region of the image where the License Plates will travel.
My Hikvision camera that is dedicated to capturing license plates would not allow me to make any configuration changes. I won't go into the months I spent researching and trying different options. I called Hikvison tech support. They did not want to help since most of my cameras were purchased on Amazon, Newegg or from China. Luckily a couple were able to get me through to tech support, BUT, they wanted to make sure the firmware version was updated before they would proceed. The camera would not allow me even upload a new firmware.
So, what was the problem?
After all this time, it turns out... MS Edge is not Internet Explorer. Yup... I was using the stupid E on the taskbar (which turns out to be Edge)... Once I ran I.E., the config files were modifiable...
Tonight I find out if changing night capture to 1/500 improves the License Plate image quality. Also, I set the ROI to only the region of the image where the License Plates will travel.
yes, ROI is Region Of Interest, Not aRea. silly me. whatever...
"MS Edge is not Internet Explorer.". nope. hadn't even occurred to me that to clarify that when i said "make sure to use IE". sorry.
Anyways, looks like you're getting closer. I'd experiment with reducing the contrast and/or gain somewhat, judging from your night shot.
My LPR cams have both contrast and gain about 25% (for the Huisuns...)
"MS Edge is not Internet Explorer.". nope. hadn't even occurred to me that to clarify that when i said "make sure to use IE". sorry.
Anyways, looks like you're getting closer. I'd experiment with reducing the contrast and/or gain somewhat, judging from your night shot.
My LPR cams have both contrast and gain about 25% (for the Huisuns...)
bigbadw
Getting the hang of it
- Sep 16, 2014
- 203
- 42
pozzello, thank you! I am definitely getting "fuzzy" "blurry" captures right now, just like you say. So, I just set updated the settings to 25% on both Contrast and Gain.
I really need to build that test setup recommended by nayr so that I don't have to wait for passing vehicles to find out....
I really need to build that test setup recommended by nayr so that I don't have to wait for passing vehicles to find out....
@cam235, are you scripting OpenALPR on Linux or Windows? which build?
Yah, that truck image is a tough one. you've also got the big "Y6534" up above the real plate to confuse things.
That's another reason I have two LP cams, so I get 'em coming and going.
If one plate (front or back) isn't legible for some reason, the other may well be...
Yah, that truck image is a tough one. you've also got the big "Y6534" up above the real plate to confuse things.
That's another reason I have two LP cams, so I get 'em coming and going.
If one plate (front or back) isn't legible for some reason, the other may well be...
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nayr
IPCT Contributor
I ordered a 25mm M12 lens, my 4431M I just installed I am going to see if it'll fit inside of.. if it does Im thinking of hitting up the intersection infront of my house where those shots were fired earlier this year..