Defocus blur estimation in calibrated multi-view images for 3D archaeological documentation

Defocus blur in images deteriorates the quality of image-based textures for 3D archaeological models. We propose a method to estimate the defocus blur in calibrated multi-view images based on photographic optics. Our method estimates the defocus blur maps without any modification to cameras or using any statistical model of images. After the focus distance of each image is estimated from the reconstructed 3D models with physical scale, the near distance dn and the far distance df of acceptable sharpness from the view point are calculated. We set the colour of the model vertex to white if the vertex’s distance from the view point is within the interval between dn and df, otherwise black. Finally we render the 3D model into a defocus map using the intrinsic and extrinsic parameters of the camera. The obtained defocus maps can be utilized as masks to generate an all-focused texture map for the reconstructed 3D archaeological model. Experimental results on real data demonstrate the effectiveness of the method.