After determining the line frequency for image capturing on the object, the control module 19 may transmit a pulse control signal to the second image capturing module, and the second image capturing module is triggered to perform image capturing on the chassis of the vehicle with the determined line frequency. The pulse control signal contains the determined line frequency.

The device provided by this embodiment may be used to implement the technical solution of the method embodiment shown in FIG. 7. The implementation principle and technical effects are similar, and details are not described herein again.

The structure of the device of this embodiment is basically the same as that of the eighth embodiment, except that in this embodiment, the control module 19 determines the number of pixels that the image of the object passes through per unit time on the imaging plane of the first image capturing module, can specifically include:

determining relative positions of a feature point of the object in the i-th image and in the (i+1)-th image, wherein i is an integer and 1≤i<m, and m is the total number of the images captured by the first image capturing camera;

determining the number of pixels n for the feature point between the two determined relative positions in the i-th image and the (i+1)-th image; and

determining the number of pixels V_p that the image of the object passes through per unit time on the imaging plane according to the following formula;
V_p=n/t;

where t is the time interval between the capturing of the i-th image and the capturing of the (i+1)-th image.