A sender produces a background video image 4 from a reference video image 1 and a depth map 3 and synthesizes the background video image 4 in a background buffer 5. A projection converting matrix 6 for synthesizing is calculated. A receiver receives the reference video image 1, the depth map 3 and the projection converting matrix 6. The receiver produces a free viewpoint video image 11 and a background video image 12. The background buffer 13 is dynamically renewed. The free viewpoint video image 11 and the image in the background buffer 13 are synthesized with each other, and the background video image in the concealed regions in the free viewpoint video image are complemented to obtain the complemented image 14.