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This app will log vehicular traffic on a road or thoroughfare. It will also measure the speed of each vehicle and determine if the speed limit is being broken. It can be configured to text you if someone exceeds the speed limit that you set. The pictures are strategically taken to achieve the best possible view of a vehicle's license plate. Additionally, the pictures are uploaded to Google Photos if you wish.
Set up Vizy in the location that you think works best. Here are the general guidelines for setting up Vizy.
Begin by turning on your Vizy and pointing your browser to it. (Please refer to the getting started guide if you need help with connecting to your Vizy, etc.) Run the Radar application by clicking on the ☰ icon in the upper right corner and selecting Apps/examples. Then scroll over to Radar in Apps, then click on Run.
select app
You'll be presented with a screen similar to below. The image at the top of the screen is the live video feed of what Vizy sees (for example, the road). Various controls (buttons, sliders) are shown below the video feed, which we'll describe in more detail.
app pic
To test, take your hand and swipe it across the image such that your hand appears on one side of the image and exits the opposite side of the image. It should detect your hand and estimate its speed as shown below.
hand
You'll notice that when detecting vehicles (or your hand), the recent detections are displayed below the live feed with the measured speed.
picture of media queue
The Radar application measures the distance a vehicle travels between each frame and then fits a straight line. This measurement is quite accurate, but it needs to be calibrated to accurately associate the time with the actual speed (either kph or mph). This can be done by either estimating the speed of a vehicle, or it can be done by driving in front of Vizy at a known speed. Because of camera dynamics, the speed will need to be calibrated for both directions on the roadway because lanes closer to Vizy's lens have faster apparent motion than lanes further away from Vizy's lens. (Currently, the Radar application assumes there are only two lanes, one for each direction of travel.)
To calibrate, just click on the image that contains the vehicle that you know the speed of. Then click anywhere within the image to bring up the calibration dialog.
calibration dialog
Type in the speed and click on Calibrate
In most countries, vehicles moving left to right will be closer to Vizy's lens than vehicles move right to left. This means that the speed will need to be calibrated in both directions