Recursive Line-based Algorithm for Hole-filling in DIBR Images

Depth-image-based rendering（DIBR） is an image synthesis method for rendering virtual free viewpoint images from depth images.However,virtual images generated by DIBR usually contain holes,which are spatial regions occluded by foreground objects.Many methods have been proposed to eliminate these holes.Criminisi and template matching are two of them.In this paper,a new hole-filling algorithm based on recursive-line is proposed to reduce the mismatches caused by the noise around contours of holes in Criminisi and template matching.First,according to the direction of view-switch,contours of holes in background area are widened to reduce the foreground noise from location deviation of depth image and view image.Second,in the ergodic hole-filling process,contours of holes in background area are extracted as filling lines.Only patches on filling lines can be filled,which reduces the number of candidate patches as well as gives high priority to background patches.Experimental results show the proposed algorithm gives higher PSNR than Criminisi algorithm by 1.617 3,and higher PSNR than depth-based template matching by 1.310 5.Proposed algorithm is capable of effectively reducing the errors in hole-filling and improving image quality.