The statistics for my street segment seem strange to me.
The data seem strange to you? Give Telraam some time to calibrate. It may take a few days. The classification of vehicles (cars/large vehicles) can also sometimes involve a slight margin of error. Want to know more about Telraam's calibration? Read the following article: "Telraam calibration".
Also check the condition of your camera. Maybe the camera is not placed properly, and the image is not of good enough quality to count. In order to check the camera position, read this: "Camera position/checking images".
Telraam is constantly under development. It is therefore possible that some data is not (yet) completely correct. We are working on creating automated solutions to filter out bad data, but it's not quite there yet.
What strange things can be observed?
- On certain days or at certain times, the car/bike/large vehicle split may not reflect reality. There are several possible causes, and they vary depending on the Telraam. For example, this can be caused by the position of the sun, which can make the shadows of cars or bikes appear larger than they really are. Telraam detects the whole vehicle as one object, so it is possible that the wrong category is considered.
- According to Telraam, my street is heavily used by large vehicles. Is this correct?
Probably not. The difficulty between cars and trucks is the presence of vans. It is possible that large cars (SUVs, Pickups,...) are counted as trucks and small, low profile vans are identified as cars. Telraams that have been active for a short time use a generic (and therefore less accurate) method to establish this difference. Some Telraams will therefore have far too many (or far too few) trucks. This improves when several weeks of data are available for each Telraam. Such an update is done about once a month. The distinction between cars and large vehicles will continue to improve as more data becomes available: so keep counting!
- Cyclists, pedestrians, cargo bikes, groups of cyclists,... How does Telraam count it all?
The difference between cyclists and pedestrians is not obvious either, especially if several pedestrians or cyclists are riding together. Recognition of the category (cyclist/pedestrian/auto/large vehicle) is then made according to size and speed. Cyclists pushing their bikes or pedestrians with strollers are then counted as cyclists, joggers, even if they are going fast, will be identified as pedestrians. Similarly, some cargo (fast) bikes or bike+trailer combinations will be counted as a car. Groups of cyclists together form a single large object and represent a specific situation that Telraam can hardly distinguish: they will then be counted as a car.
Again, the more data we collect all together, the better Telraam will eventually be able to tell the difference. You wish more info regarding the vehicle classification? Read the following article: "How are the different types of vehicles classified and differentiated?"
- What happens if there is a traffic jam?
If there is a (long) traffic jam (no movement for several minutes), Telraam will not work. Cars will not suddenly be counted as large vehicles. Telraam simply does not count well. This will be expressed as a "poor quality" label.
Despite these explanations, the data you receive seem too strange?
You can get more detailed and (scientific) info in the following article: "Potential inaccurencies in Telraam"
Send us an e-mail to the following address, explaining your situation: firstname.lastname@example.org
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