Method for adjusting dynamic exposure of camera in automatic driving

Abstract

The invention provides a method for adjusting dynamic exposure of a camera in automatic driving. The method comprises the following steps: (1), demarcating the camera to obtain the maximal exposure time Emax and the minimal exposure time Emin of the camera and the maximal grey level Gmax and the minimal grey level Gmin of an image photographed by the camera; (2), extracting an image in the current frame of the camera, comparing the average grey level Gavg of the image in the current frame with the Gmax and the Gmin so as to correct the Gavg, and obtaining a pre-adjusted exposure time Etmp of the current image according to the Gavg and the exposure time Ex' of the previous frame of image; and (3), correcting the Etmp after comparing the Etmp with the Emax and the Emin so as to obtain the optimal exposure time Ex, which can be used when the next frame of image is acquired, and then, returning to the step (2). According to the invention, dynamic adjustment of the exposure time of the camera in motion is realized; therefore, the camera is adaptive to change of surroundings of a high-speed mobile intelligent vehicle; the optimal exposure is continuously adjusted along with change of times and environments; and thus, the image definition obtained by the camera is obviously improved.

Description

technical field [0001] The invention belongs to the field of automatic driving, and relates to an image perception and image processing module in automatic driving or safety assisted driving, in particular to a method for adjusting dynamic exposure of a camera in automatic driving. Background technique [0002] The camera is one of the most commonly used sensors in an automatic driving system or a safety assisted driving system. Under normal circumstances, the automatic driving system analyzes the images captured by the camera to achieve the purpose of perceiving the surrounding environment and assisting driving safety. [0003] In order to ensure that the camera in the smart car can obtain a good quality image, it is necessary to adjust many parameters of the camera. Among the many parameters of the camera, exposure is a very important parameter. If the image is too bright and overexposed or too dark or underexposed, it will greatly affect the reading and analysis of imag...

AI Technical Summary

Problems solved by technology

Different from the static camera, with the changes of the surrounding environment of the high-speed moving smart car, the moving camera is faced with the ever-changing lighting environment, so the moving camera needs a dynamic exposure adjustment that continuously adjusts the exposure over time method, the existing automatic exposure adjustment method for still cameras cannot meet this requirement

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