Apparatus for preparing an access unit stream of consecutive access units, representing media content, for a transmission via a transmission signal, the apparatus being configured to generate a sequence of logical frames from the access unit stream by consecutively inserting the consecutive access units into a useful data section of the logical frames of the sequence of logical frames; and providing each logical frame into which a begin of an access unit falls, with an access unit table comprising, per begin of the access units falling into the respective logical frame, a pointer pointing thereto. wherein the apparatus is configured to provide each logical frame with a logical frame header such that the logical frames headers have a length constant for all logical frames, wherein the logical frame header indicates the absence of an access unit table in the respective logical frame for logical frames into which no begin of any of the consecutive access unit falls, and the length of the access unit table of the respective logical frame for logical frames into which the begin of at least one of the consecutive access units falls, wherein the apparatus is configured to generate the sequence of logical frames such that the access unit table borders, or is constantly offset from, the rear end of the logical frames and the logical frame header borders, or is constantly offset from, the leading end of the logical frames so that the useful data section is a connected portion extending, for logical frames into which a begin of an access unit falls, between the access unit table and the logical frame header, respectively, and for logical frames other than the logical frames into which a begin of an access unit falls, between the logical frame header and the rear end of the logical frames, wherein the apparatus is configured to provide each access unit table with an access unit table entry per begin of the access units falling into the respective logical frame, each access unit table entry comprising a pointer pointing to a respective one of the begin of access units falling into the respective logical frame, wherein the apparatus is configured such that beginnings of the access unit table entries are spaced apart from the rear end, or from a position within the logical frame 20, having a predetermined constant offset therefrom, in units of a constant length, and such that in each access unit table, among the begins of the access units falling into the logical frame comprising the respective access unit table, the first along the useful data insertion direction is pointed to by the pointer of the access unit table entry of the access unit table entries which borders the rear end of logical frame, with the begins of the access units following in useful data insertion direction being pointed to by pointers of access unit table entries following along a direction contrary to the user data insertion direction. the absence of an access unit table in the respective logical frame for logical frames into which no begin of any of the consecutive access unit falls, and the length of the access unit table of the respective logical frame for logical frames into which the begin of at least one of the consecutive access units falls,