Composition and transmission of pictures in mobile environment by using extraction of focused region

When a picture is compressed in MPEG video, the image quality of important regions is maintained without changing the total amount of information; this is done by assigning a high information priority to the important region. The paper proposes a method to modify a quantizer scale according to the importance estimated by a quantity of depth of focus. Image quality of an important region does not deteriorate much, even if the total amount of information is decreased.