Research And Application Of Image Enhancement Based On 3d Grid Smoothing

Digital Home Industry is one of the national strategic emerging industries in China, as well as one of the important industries in the"12th Five-year Plan"of the Guangdong Province. Its development is significant to people and the society. Digital TV is an important component. The digital TV based on flat-panel display (FPD) technology is the core of the high-definition interactive application in digital home. The optimization of FPD has been a challenging problem in its application. With the flat panel project of the Guangdong province as the research background, this thesis discusses and proposes the image enhancement methods to reduce display distortion, edge blur, noise amplification, and tone distortion.Focusing on the technology in image detail enhancement, high-dynamic-range image and tone enhancement, this thesis proposes a method for image detail enhancement and tone enhancement with a 3D grid smoothing model. It firstly makes a new explanation to the 3D grid with the local histogram theory, and presents its efficient smoothing function in which an 2D nonlinear spatial smoothing operation can be transformed to 3D linear smoothing operation and the computation efficiency is improved. Then it applies the method to detail enhancement and tone enhancement respectively. The comparison is made between the results by the proposed method and those by the guided filter and the weighted least square filter. In addition, this thesis applies the 3D grid to the joint bilateral filter and extends its application. Experiments are made with the joint 3D grid smoothing to realize the shadow inhabitation and denoising of no-flash images. Satisfied results are obtained. Furthermore, the implementation process and codes based on the approach are provided. A system framework is designed for the application to the digital TV application. The experiment results demonstrate that the proposed approach obtains an efficient performance in image detail enhancement and tone enhancement,preserving clear edges and smoothing noises, improving images display on HDTV. It meets the demands of practical application.