A method for bandwidth-optimized transmission of a HDTV data stream via an IP-based distributor network to at least one end subscriber which is connected to the IP-based distributor network via an access port of predetermined maximum bandwidth, comprising the method steps of: a) providing, by a broadcasting service, an HDTV data stream representing an HDTV program; b) encoding the HDTV data stream into a main video data stream which has a lower bandwidth than the HDTV data stream; c) encoding the HDTV data stream into at least one differential video data stream that cannot be displayed alone; wherein step c) comprises the steps of: decoding the main video data stream; delaying the HDTV data stream by a predetermined time; forming a differential signal from the delayed HDTV data stream and the decoded main video data stream; and encoding the differential signal into the differential video data stream; d) feeding the main and differential video data streams into the IP-based distributor network; e) transmitting the main video data stream or the main video data stream and the at least one differential video data stream to the at least one end subscriber, based on the available bandwidth of the access port of the at least one end subscriber; wherein the currently available bandwidth of the access port of the at least one end subscriber is determined even during playback of the HDTV program and the transmission of the differential video data stream is controlled based on the determined bandwidth; f) decoding the main video data stream and playback of the HDTV program in lower image quality; or g) decoding the main video data stream and the at least one differential video data stream and playback of the HDTV program in enhanced image quality. a) providing, by a broadcasting service, an HDTV data stream representing an HDTV program; b) encoding the HDTV data stream into a main video data stream which has a lower bandwidth than the HDTV data stream; c) encoding the HDTV data stream into at least one differential video data stream that cannot be displayed alone; wherein step c) comprises the steps of: decoding the main video data stream; delaying the HDTV data stream by a predetermined time; forming a differential signal from the delayed HDTV data stream and the decoded main video data stream; and encoding the differential signal into the differential video data stream; decoding the main video data stream; delaying the HDTV data stream by a predetermined time; forming a differential signal from the delayed HDTV data stream and the decoded main video data stream; and encoding the differential signal into the differential video data stream; d) feeding the main and differential video data streams into the IP-based distributor network; e) transmitting the main video data stream or the main video data stream and the at least one differential video data stream to the at least one end subscriber, based on the available bandwidth of the access port of the at least one end subscriber; wherein the currently available bandwidth of the access port of the at least one end subscriber is determined even during playback of the HDTV program and the transmission of the differential video data stream is controlled based on the determined bandwidth; f) decoding the main video data stream and playback of the HDTV program in lower image quality; or g) decoding the main video data stream and the at least one differential video data stream and playback of the HDTV program in enhanced image quality.