A method and apparatus for encoding (622) digital image data wherein a
region of interest (606) can be specified either before the encoding
process has begun or during the encoding process, such that the priority
(616) of the encoder outputs are modified so as to place more emphasis on
the region of interest, therefore increasing the speed and/or increasing
the fidelity of the reconstructed region of interest. The system,
therefore, enables more effective reconstruction of digital images over
communication lines.