Method and apparatus for determining the quality of an encoded media signal

Means for determining a quality of an encoded media signal, with a Ubertragungsstorungsbestimmer (14) which is adapted to continuously monitor the encoded media signal (22) at least over periods of time on transmission interference to and identify transmission interference-free and transmission subject to interference phases based on the monitoring; and a Qualitatsbestimmer (16) which is adapted to Analysis time segments to be placed so that the same are aligned in time to the transmission fault-free phases, namely, so that the analysis time intervals as completely as possible in the transmission fault-free phases (40) lie, so that the analysis time segments each having a total length of time in a predetermined fixed range of 2-30 s, and determining a quality of the encoded media signal only in the analysis periods.