High-dynamic-range image acquisition method of single exposure

Abstract

The invention discloses a high-dynamic-range image acquisition method of single exposure. The method comprises the following steps of: comparing an ideal average brightness value B0 with an average brightness value of all pixels of a bright image and a dark image acquired through exposing a charge coupled cell within an initial exposure time t0; calculating out a new exposure time tnew through a digital signal processor; exposing the charge coupled cell within the new exposure time tnew to acquire a bright image and a dark image and respectively comparing a threshold value S with brightness values of the first pixel to the Nth pixel of the bright image and the brightness values of the first pixel to the Nth pixel of the dark image; and acquiring the brightness values of the first pixel to the Nth pixel of a high-dynamic-range image through a formula, wherein the image comprising the brightness values of the N pixels is the high-dynamic-range image. By acquiring a high-dynamic-range image through the single exposure of an image sensor, the invention solves the technical problems of small dynamic range, unavailability in a motion scene, and the like of a traditional image acquisition method and has the advantage of low production cost.

Description

technical field The invention relates to the technical field of image processing, in particular to a single-exposure high dynamic range image acquisition method. Background technique A charge-coupled device (CCD) is a widely used image sensor. However, a serious problem faced by this technique is the limitation of its dynamic range. The dynamic range of natural scenes mostly exceeds 100dB, while most traditional imaging technologies can only reach about 60-70dB. This results in images captured in scenes with a large dynamic range having both overexposed and underexposed areas, and both overexposure and underexposure mean loss of image detail. In order to solve the above problems, some people have proposed improved methods, which can be divided into two types: one is based on multiple exposure methods to fit high dynamic range images (HDRI); the other is to obtain HDRI directly from a single exposure. . The method of fitting HDRI based on multiple exposures is widely us...

AI Technical Summary

Problems solved by technology

However, most of the proposed improvements are limited to the improvement of the image sensor itself, such as changing the cell structure of the sensor to directly obtain images with a large dynamic range

These methods are certainly feasible, but the cost of redesigning the photosensitive chip and tape-out is very considerable, which directly limits the practical application of these methods

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