Hybrid fractal image coding with quadtree-based progressive structure

•A progressive structure is proposed for fractal image coding.•The quadtree depth information is utilized in the progressive structure.•A hybrid fractal image coding using traditional and no-search methods is suggested.•A better progressive performance is reached compared with the traditional approach.•A threshold is employed to balance the image quality and encoding efficiency.

A progressive structure which takes the quadtree depth into consideration is proposed for fractal image coding. Simulation results show that its image quality at different received data rates is better than that without considering the quadtree level. Then, a hybrid fractal image coding scheme based on traditional and no-search fractal image coding with the proposed progressive structure is suggested. The image quality and compression ratio can be controlled by a threshold, which makes it downward compatible to the no-search fractal image coding. Experimental results justify that the progressive performance of the proposed scheme is better than that of traditional fractal image coding.