High dynamic-range image synthesis method and device

Abstract

The invention discloses a high dynamic-range synthetic imaging method and device, aiming at providing a method for synthesizing two pieces of images with lower dynamic ranges into a piece of image with higher dynamic range. The high dynamic-range synthetic imaging method comprises the steps of: shooting a same scene at different exposure time to obtain two pieces of different exposed images; respectively converting the two different exposed images to be in exposure value spaces according to response curves of a shooting device; weighted-synthesizing scene brightness which is calculated by utilizing exposure value and exposure time according to brightness of the two pieces of images; and simulated-exposing the synthesized scene brightness through the response curves to obtain the image with high dynamic range. According to the invention, two pieces of different exposed images are synthesized, and thus the difficulty of image alignment is reduced; moreover, the operand and the required storage space in the processing procedure are reduced, so that the high dynamic-range synthetic imaging method and device can be applied to a small-sized handheld device; and at the same time, the image with high dynamic range is rich in details at light parts and shadow parts, and the color and the details of the image are in conformity with those of the original scene.

Description

technical field [0001] The invention relates to the field of digital image processing, in particular to a high dynamic range image synthesis technology in image processing. Background technique [0002] In the process of image acquisition, since the dynamic range of the scene to be shot is greater than that of the shooting device, and only one global and fixed exposure method can be used for a single shot, only part of the scene in the scene to be shot can be correctly exposed. Other scenes are either overexposed or underexposed. In the overexposed part, because the brightness is close to saturation, the details of the scene to be shot are all highlighted in white and cannot be distinguished; in the underexposed part, due to the low sensitivity of the shooting equipment, it is difficult for the slight brightness change of the scene to be shot to be reflected in the image. The scene details are lost, and the resulting image brings great inconvenience to the post-processing. ...

AI Technical Summary

Problems solved by technology

[0005] In order to overcome the shortcomings in the prior art that the number of different exposure images required is large, resulting in a large amount of computation and large storage space, which are not suitable for small handheld devices, the present invention provides a high dynamic range image synthesis method and its device , the present invention uses two frames of images with different exposures for high dynamic range synthesis, which reduces the difficulty of image alignment; at the same time, due to the reduction in the number of images, the amount of computation and the required storage space in the processing process are greatly reduced, making it possible to for small handheld devices

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