TOF Cameras Development for Bus People Counting
With the continuous development of public transportation, intelligent transportation has become one of the research hot area. As an important information resource for the intelligent development of public transport, bus people counting provides decision-making basis for intelligent vehicle scheduling and scientific route planning of bus traffic management departments. The real-time and accurate information obtained from bus people counting is connected with the client, which can also facilitate passengers to plan travel routes and times and facilitate passengers to travel.
The TOF camera is used to shoot the video with depth information. The captured image of each frame is recognized by appropriate classification on the single chip microcomputer, and the recognized target is judged whether to enter or go out through motion analysis for bus people counting.
TOF camera for people counting
Two. Product performance advantages
Technology path comparison (TOF camera and binocular camera): TOF camera technology and binocular measurement system belong to non-invasive 3D detection, and their application fields are also very similar, but TOF camera technology has completely different 3D imaging principles. Binocular stereo measurement is carried out by matching the left and right stereo pairs, and then by triangulation, while TOF camera calculates the distance of the target through incoming and reflected light detection.
For head counting based on the principle of binocular stereo vision imaging, this method has a large amount of calculation. Because the traditional optical sensor and infrared light supplement are used, it has high requirements for ambient light, and the accuracy is not very high in the case of poor lighting conditions.
Compared with the binocular stereo vision algorithm, the algorithm of TOF camera is simpler, which can carry out three-dimensional detection more quickly and accurately, and the depth calculation accuracy can be basically stable to the centimeter level. Therefore, the use of TOF technology can better carry out the operation of head detection in the actual application scene.
Three. Market prospect and Application
This product can be conveniently installed inside the roof of high-speed railway or bus door, which is convenient for photographing the situation near the door. The tof camera captures the image of the door. After processing, the single chip microcomputer obtains the number of people entering and leaving the door in real time, and ensures that the recognition accuracy is higher than the existing equipment in the market under the condition of low cost.
Four. Disadvantages
At present, the cost of TOF camera is relatively expensive. Compared with the binocular people counter, the overall cost of TOF technical scheme is still more than twice as high. In addition, the TOF camera needs to be installed at a position higher than 230 cm, which is often lower than this height in the actual bus installation, most of which are lower than 200 cm. Therefore, it is subject to many restrictions.