A Method of Re-lighting Face Image

Abstract

The invention discloses a method for re-illuminating a human face image, comprising: performing face recognition on a two-dimensional human face image to obtain two-dimensional feature points; performing three-dimensional reconstruction of the face according to the two-dimensional feature points and three-dimensional face model data to generate a three-dimensional face image The 3D grid of the face image; according to the lighting rendering parameters and the pre-built lighting model, the 3D grid is rendered with local lighting to generate the first 2D facial lighting map; the skin color detection is performed on the 2D face image to obtain the 2D The skin color probability value of the face image; according to the skin color probability value, the first two-dimensional facial light map is protected for the non-skin color area, and the second two-dimensional facial light map is obtained; the face contour of the second two-dimensional facial light map is The edge is expanded to obtain the third two-dimensional facial lighting map; the third two-dimensional facial lighting map is re-light-fused with the two-dimensional face image to generate a lighting result map. The technical scheme provided by the invention is simple and easy to implement, fast and efficient, and has strong user controllability.

Description

technical field [0001] The invention relates to the technical field of digital image processing, in particular to a method for re-illuminating a human face image. Background technique [0002] In recent years, portrait beauty and makeup applications have become popular among young users. In order to obtain good shooting results, users usually need to be in a good lighting environment and lighting conditions. Due to the lighting conditions and the position of the light source, it is easy to lose the three-dimensional details of the face, resulting in a flat face after makeup, which lacks a sense of reality. As an improvement to the effect of the above-mentioned applications, a method of performing facial relighting (Relighting) on ​​the portrait photos in the later stage is proposed, that is, a method of relighting the face image. The method is to adjust the face image of the target person according to the change of illumination or external environment, and generate a face i...

AI Technical Summary

Problems solved by technology

[0004] From the above methods, it can be seen that the existing face image re-illumination technology needs to prepare a large amount of sample data in different face poses in advance.

At the same time, considering that different races and skin colors have different facial structures (face shapes) and different light reflectances, this greatly increases the number of samples required for preparation

Based on the interference of these environmental factors and the technical solutions adopted, it is difficult for the above-mentioned methods to accurately reconstruct and restore the 3D structure of the face

At the same time, due to the skin color and different facial structures, it is also difficult to find out the exact position of the light source and the correlation coefficient of the material

In short, the existing technical solutions are more complicated, difficult to master, and less effective in implementation

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