提出了一种基于小波变换与纹理移植相结合的人脸衰老化合成(绘制)方法.首先,将衰老模板进行二维离散小波变换(2Ddiscrete wavelet transform,简称2DDWT),提取出承载衰老皮肤纹理特征的高频子图与高通滤波后的低频子图然后,将其与目标人脸图像的对应分量进行置换与融合,利用小波重构来完成衰老纹理向目标人脸的移植;同时,提取出年轻人群到年老人群在脸形上的平均变化,将其作用在目标人脸上以增强衰老化合成的效果.结合色彩渲染技术,设计实现了真实感人脸衰老化绘制的完整技术框架-实验部分分别将该方法应用于东西方人脸以及艺术图片,绘制结果显示出了具有真实感和感染力的效果与基于PCA(principal components analysis)。3D渐变模型、比例图等方法相比,该方法较好地解决了在人脸衰老化绘制中真实感与易操作性之间难以折衷的问题.
A facial ageing synthesis (rendering) method based on combination of wavelet transform and texture transplant is proposed in this paper. Firstly, 2D discrete wavelet transform (2D DWT) is performed on ageing templates to extract the high-frequency sub-images and high-pass filtered low-frequency sub-images, which contain the texture characteristic of ageing skin. Then the corresponding sub-images of target facial image are replaced and fused with them, and the transplant of ageing texture towards target face is achieved through wavelet reconstruction. In addition, the average variation of the facial shape between young population and old population is extracted, and imposed onto the target face to enhance the ageing rendering effect. Combining with color rendering technique, an integrated framework for photorealistic facial ageing rendering is designed and implemented. In the experiment, the proposed rendering framework is applied to oriental face, western face and art painting image, and the rendering results show the realistic and impressive effects. Comparing with PCA (principal components analysis)-based method, 3D Morphable model, and ratio image method, this method contributes a solution for the problem of tradeoff between photorealistic effect and easiness to operate for facial ageing rendering.