Recognizing license plates was essentially impossible with the 2 1080p dashcams we tested (see: Testing CarCam and Testing Advanced Drivercam). The problem was the FoV of the units. It appears that many buyers prefer wide FoVs (100+ degrees) to ensure that they do not miss any of the periphery. The problem is the FoV is so wide that even a car only 20 feet in front of the camera is very hard to make out. As such, I'd be very careful about verifying the recognizing nr plates requirement.
Axis has a mobile standalone recorder but that's comically expensive compared to what I would expect a taxi company is looking to pay. I suspect there's a low cost HD mobile kit provider but I do not know personally.
We have a product that may suit - the NVR-404C it can record up to 4 channels at 1080p 25fps if you need pricing info please contact the relevant LILIN branch office, if you are US based that would be Los Angeles on 1 (626) 930 1000.
Storage can be solid state but is limted to a single internal drive.
Feel free to post any questions here and I will try to help.
Seneca | IPVMU Certified | 11/22/13 10:22pm
John is correct in that the camera makes the system capture what you desire. A couple of School bus specialist vendors have cameras that mount on the side of the bus to capture license plates of the folks who pass a stopped school bus. I dont have the name handy but I seem to recall John mentioned them within the past couple of months.
A Whose units have you evaluated so far?
Here are a few questions that you should be asking based on what my company deals with in this area:
Do you need integrated POE?
Do you need Ignition controls with timers?
Do you want hot swap SSD and lockable drive bays? <note... do not used mechanical drives in a true mobile environment...they do not last long>
For our vehicles, we use a budget OEM mobile video recorder. 25fps all channel + audio. Optional 3G.
For the anlogue version, we use 4x 700TVL mini dome. We are now trying out a hybrid version which will accept both analogue and network cameras. 700TVL is good enough for license plate identification, but we are thinking of switching the front cameras to HD.
From experience, we need aviation connectors and built-in vibration stabilisers to withstand the vehicle's vibration and to protect the HDD recording. HDD is 2.5" surveillance grade. SSD's capacity is insufficient and costs too much. We are from the the equator region, so the recorder must be able to withstand up to 65 degrees celsius. That' about the max for the HDD too.
Seneca | IPVMU Certified | 11/25/13 01:38pm
The school bus company mentioned on IPVM is gatekeeper systems. I did a quick check of the temperature and they do list 65C as the top end. Their systems are DVR/Analog types.
Regarding SSD capacity..... 1TB are coming soon (I have one in my lab) but of course they will be pricey. If one sticks with the 300-600GB size...favoring the smaller side.... the expense (in the USA) is not as wide as it used to be.
A 4CIF good quality image will generate appx 1Mbit stream. If continuous recording is used, and 7 days is how long to keep the data before it gets 'offloaded', then the system will need appx 300GB. Allowing the system to use Motion or Triggered recording will extend the number of days at that same capacity.
The higher temperature requirement means that the components used in the system MUST be higher grade...which means more expensive. If you continue to stay with bargain systems....then you will be replacing them a lot because they will fail much quicker. The same argument applies to SSDs as well. Mechanical drives do NOT like to be vibrated while they are working and do not like to be much more than 50C or else they will suffer a premature fail. SSDs have a much higher tolerance for those two metrics.