the present invention fig2 a 2 b 2 c 2 d and 2 e represent the block values at respective quantizing values of q 5 4 3 2 and 1 e g fig2 a represents the integer portions of the results of a division of the values of fig2 e by 5 reference is now made to fig3 a 3 b 3 c 3 d and 3 e which are representation of a layer structure in accordance with another preferred embodiment of the present invention fig3 a is a visual representation of the block of fig1 at the highest quantizing value and is identical to fig2 a fig3 b represents the difference a between the representations of fig2 a and 2b so that adding the representation of fig2 b over the one of fig3 a yields in the representation of fig2 b similarly fig3 c represents the difference u03b4 between the representations of fig2 b and 2c fig3 d represents the difference u03b4 between the representations of fig2 c and 2d and fig3 e represents the difference u03b4 between the representations of fig2 d and 2e the newly compressed frames at each of the compression levels fig2 a 2 b 2 c 2 d and 2 e can now be used to reproduce a representation of the media stream deteriorated according to the compression level or be sent to a far end.