Process for changing the resolution of MPEG bitstreams, and a system and a computer program product therefor

摘要

A process and a system is described for generating an MPEG output bitstream starting from an MPEG input bitstream. The output bitstream has a resolution modified with respect to the resolution of the input bitstream. In the input bitstream, first portions that substantially do not affect and second portions that do affect resolution variation are distinguished. The second portions are then subjected to a function of modification of the resolution obtained by filtering the second portions in a domain of the discrete cosine transform, and then are transferred to the output bitstream. A corresponding computer program product is also provided.