An important region can be of any shape. There may be several regions with various degrees of importance.
0411012XXX SAT 0 IDIDIDIDIDID 05051000 0040 0000 0000 0000000LAPPRENO [10,(31,31)-(63,63)]
not every detail of the picture is equally important to the observer. For example, the area of the hurricane eye on a satellite image should be of high resolution, while the tight cloud cover of the hurricane body is less informative and may be rendered with a lower resolution, though it cannot be completely discarded. In disseminating the weather information to ships, a meteorologist at a particular ship needs very accurate data on cloud cover, wind direction, temperature, etc. just in the vicinity of his ship. The information about what is going on outside that small area is used for prognosis and does not have to be of very high precision. Accordingly, the amount of loss and inaccuracy that can be tolerated during the communication varies not only from one user to another but also from one region of the image to another. This raises the problem of a non-uniform, lossy compression, i.e., compression where the loss varies with the location/features/frequencies, etc., and tailoring such compression to a particular user and circumstances. Preserving the information during compression to the extent the user needs, but not more, helps to drastically reduce the amount of data that has to be transmitted.