Display Technology Of High Color Depth Image

In recent years,with the continuous advancement of digital image technology,high dynamic range images have the characteristics of wide dynamic range,large color space,and rich information levels.Therefore,they are favored by researchers and are gradually used in meteorology,military,medical,and transportation.However,display devices in research work or daily life cannot directly display high dynamic range images.It is necessary to compress High Dynamic Range(HDR)images through tone mapping algorithms and map them to be directly displayed in daily display devices.Therefore,the tone mapping algorithm has become an extremely important content in the research of high dynamic range images.The purpose is to compress HDR images and retain as much detailed information as possible during the compression process,while ensuring that no color distortion or poor contrast occurs during the mapping process.,Halo or other phenomena.The traditional edge-preserving filtering algorithm generally used the processing method of compressing the dynamic range of the basic layer and enhancing the detail layer.This paper conducts in-depth research on the relevant theories of HDR images,investigates various algorithms such as global tone mapping and local tone mapping,and selects the edge-preserving filter method based on the method,develops various improvements to the traditional method.And verify the algorithm from the subjective and objective level.The main work includes the following aspects.(1)Research and analysis of layered processing of edge-preserving filtering algorithm.The test analyzed the effects of different edge filters,and designed a tone mapping algorithm based on the bilateral filter algorithm.Realizes the method of converting the image from RGB space to YUV space,which separates the brightness component and chroma component of the image,and solves the problem of color flipping during the tone mapping process.Use fast bilateral filter to process the luminance component image and divide it into basic layer and detail layer to process them separately.(2)Analysis and design of the enhancement of the detailed information of the brightness map.An algorithm that can effectively enhance the detailed information of the luminance map is designed and implemented.According to the characteristics of human vision that the green component occupies an important position in the calculation of brightness,this paper adopts a detail layer processing method that is different from the traditional method,and designs an algorithm for processing the detail layer from two aspects to improve the optimization of HDR images.The color interpolation algorithm used in the display process.Based on the experimental research results,the detail layer of the luminance component map is very dependent on the detail information processing in the color interpolation process,so this paper completes the edge information enhancement of the high dynamic range image in the color interpolation.The algorithm uses the eight-direction gradient calculation method to complete the green component,and calculates the edge information of each direction at the same time to avoid the calculation of the gradient direction.According to the color difference theory,the red and blue components are interpolated on the basis of the completion of the green components,and the S-curve is used to enhance the detail layer.(3)Analysis and design of the basic layer compression of the luminance map.According to the global tone mapping algorithm,it has the characteristics of fast speed and no gradient inversion.When this article deals with the basic layer,using the idea of global tone mapping algorithm for processing the entire image,a method of separating the detail information from the basic layer is designed to solve the shortcomings of the global tone mapping algorithm that the details and contrast of the image are relatively rough.And for the problem of contrast compression,this paper uses an adaptive logarithmic mapping algorithm to compress the dynamic range of the base layer,the adaptive logarithmic mapping algorithm uses the human eye's perception curve of brightness to approach the characteristics of the logarithmic transformation function.The image contrast problem can be handled well,and the processed image can achieve the overall brightness and moderate effect.(4)Subjective and objective evaluation and analysis of tone mapping algorithms.Through subjective and objective evaluation methods and experiments,several typical tone mapping algorithms and the tone mapping algorithms implemented in this paper are compared and analyzed.The results show that the tone mapping algorithm in this paper has low time complexity.And the mapped image retains richer detailed information,the bright and dark edges of the image are processed properly,the overall image contrast is clear and natural,and the halo phenomenon is avoided.The algorithm in this paper achieves the goals of compressing the dynamic range of HDR images,accurately after color mapping,and retaining complete image detail information.The effect is relatively ideal.