The original image inpainting algorithm based on partition block of damaged region (IIPBDR) algorithm is not suitable to inpaint a damaged image with large damaged area that contains broken boundaries with large curvature because this algorithm uses a straight path to inpaint the matching broken boundaries in inpainting process. We aim to obtain a smooth curve path between any two matching broken boundaries. This smooth curve path is then used to improve IIPBDR algorithm

instead of a straight path. The following steps are performed in this study: 1) A smooth-fitting model that satisfies human visual connecting is proposed. 2) Least square is employed to search all coefficients of this model by using the prior information of the matching broken boundaries. Then

a smooth curve path between two matching broken boundaries is obtained. 3) The smooth curve path

instead of the straight path

is used in IIPBDR algorithm to inpaint two matching broken boundaries. “Improved IIPBDR algorithm based on smooth-fitting model” is proposed based on preceding studies. Experimental results indicate that compared with Bertalmio-Sapiro-Caselles-Ballester

Criminisi

IIPBDR algorithms

the improved method can increase peak signal-to-noise ratio value by approximately 2.4 dB

and the inpainted images have better visual effects. Thus

the improved method is more competent than the aforementioned algorithms in inpainting a damaged image that contains broken boundaries with large curvature. The proposed algorithm can solve the problem

in which IIPBDR algorithm is not suitable to inpaint a damaged image with large damaged area that contains broken boundaries with large curvature.