Exposure control system and method

Abstract

The invention discloses an exposure control system and an exposure control method. The exposure control system comprises an image acquisition module and a back-end control module, wherein the image acquisition module automatically adjusts an exposure time and a gain value to obtain a proper exposure time value and a proper gain value, so that the mean luminance of an acquired image is in an expected luminance range; the value of the exposure time is obtained from a value range; the maximum exposure time value in the value range is set to be an initial maximum time value; the back-end control module detects the exposure time value, modifies the maximum exposure time value to be a preset time value if the exposure time value is equal to the preset time value; and the preset time value is less than the initial maximum time value. The back-end control module in the exposure control system and the exposure control method provided by the invention locks the exposure time of a photosensitivemodule at given scene light intensity in a low light environment by adopting an interrupt signal, so that the photosensitive module still can keep a relatively higher frame rate in the low light environment.

Description

【Technical field】 [0001] The invention relates to the field of automatic exposure control of an image acquisition device, in particular to a system and method for interfering with an original automatic exposure control device through an interrupt signal. 【Background technique】 [0002] The brightness of the image collected by the image acquisition system is mainly determined by several factors such as scene light intensity, aperture size, exposure time and signal gain. Under natural conditions, the light intensity of the scene is determined by the light intensity of natural light, which is not convenient for automatic control. Therefore, in order to automatically obtain an image with moderate brightness, it is only necessary to effectively and automatically control the three quantities of aperture size, exposure time and signal gain. control can be achieved. In a common camera or CCD, the aperture size is constant, so it is usually only necessary to automatically control th...

AI Technical Summary

Problems solved by technology

And when the chip solution provider uses the photosensitive chip 120 for a camera, in a dark environment, the longer exposure time that the photosensitive chip 120 will adopt will result in a lower frame rate of the captured image Can not meet the needs, for example, the working environment of the camera is often in a dark environment such as a factory or an Internet cafe

In the prior art, the image control chip 140 cannot interfere with the running state of the ISP module 124, so the above problems cannot be solved

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