Concept for picture/video data streams allowing efficient reducibility or efficient random access

A method for decoding a data stream having a picture encoded thereinto, the method comprising

• reconstructing the picture from the data stream, and
• synthesizing a target picture on the basis of the picture by
• reading, as part of displacing information contained in the data stream, from the data stream, for each predetermined subregion of a set of predetermined subregions of the picture,
• first position information on a position of the respective predetermined subregion in the target picture area,
• second information on a position of the respective predetermined subregion within the picture, and
• information on a rotation when mapping the respective predetermined subregion between the target picture area and the picture,
• displacing and rotating each of the predetermined subregions of the set of predetermined subregions of the picture relative to an overlay of the picture onto the area of the target picture according to the first position information, the second position information and the information on the rotation,
• wherein the method further comprises reading from the data stream default filling information which indicates how to fill a portion of the target picture where none of the set of predetermined subregions of the picture lies according to the displacing information.