The invention provides a system and a method for providing a multiplexed sequence, the multiplexed sequence including at least one sequence of basic media data units/modified basic media data units, the system and method are responsive to at least one characteristics (such as quality, quality degradation, compression level and the like, a combination of at least two of the characteristics) of at least of some of the basic media data units. The invention provides a method for generating a multiplexed sequence, the method including the steps of: receiving at least one basic media data unit sequence; determining a modification priority of a plurality of basic media data units of the received at least one basic media data unit sequence; selecting basic media data units to be modified, in response to the modification priority; modifying each of the selected basic media data units to provide corresponding modified basic media data units; wherein a modified selected basic media data unit is smaller than the corresponding selected basic media data unit; replacing selected basic media data units with the corresponding modified basic media data units in response to a comparison between the basic media data units and the corresponding modified basic media data units to provide replacing basic media data units; and multiplexing replacing basic media data units and basic media data units that were not replaced to provide the multiplexed sequence.