This example shows how to detect and track cars in a video sequence using optical flow estimation.
The following figure shows the Tracking Cars Using Optical Flow model:
The model uses an optical flow estimation technique to estimate the motion vectors in each frame of the video sequence. By thresholding the motion vectors, the model creates binary feature image containing blobs of moving objects. Median filtering is used to remove scattered noise; Close operation is performed to remove small holes in blobs. The model locates the cars in each binary feature image using the Blob Analysis block. Then it uses the Draw Shapes block to draw a green rectangle around the cars that pass beneath the white line. The counter in the upper left corner of the Results window tracks the number of cars in the region of interest.