Video recording device compatible transmitter

A device for generating a digital video data stream including video codewords at a first data rate, in a format that facilitates the subsequent selection of a subset of the video codewords for inclusion in a reduced rate data stream intended for use during VTR trick playback operation, the reduced rate data stream having a second data rate that is lower than the first data rate, the device comprising:

• a video encoder for receiving video signals and encoding the video signals to generate the digital video data stream including the video codewords, each video codeword including data corresponding to one of a plurality of data types, each one of the plurality of data types representing data having a degree of utility for generating a recognizable portion of an image during video tape recorder trick play operation, the degree of utility of each one of the plurality of data types corresponding to the amount of decrease in the quality of the image portions that can be generated from the video codewords included in the reduced rate data stream that results when the codewords of the one of the plurality of data types is omitted from the reduced rate data stream, wherein data of a type required to generate recognizable portions of video images during video tape recorder trick playback operation are of a higher degree of utility than data of a type that has little impact on the quality of image portions generated during video tape recorder trick playback operation ;
• and
• a trick play video data prioritizer coupled to the video encoder for receiving the digital video data stream, and for prioritizing each of the video codewords in the digital video data stream according to a preselected prioritization scheme, the preselected prioritization scheme assigning each one of the video codewords in the video data stream to one of a plurality of at least three trick play data priority levels as a function of the degree of utility of the type of data included in each video codeword for generating a recognizable portion of an image during video tape recorder trick play operation, each one of the trick play data priority levels representing video codewords including data having approximately the same degree of utility for generating a recognizable portion of an image during video tape recorder trick play operation,
• the trick play video data prioritizer including:
• a video signal output for outputting a video codeword signal and a priority level signal.

A method of prioritizing digital video data included in a video data stream intended to support normal play video tape recorder operation, to facilitate the subsequent selection of a subset of the video data for use during video tape recorder trick play operation, the digital video data including a plurality of data units, each of said plurality of said video data units having a degree of utility for generating a recognizable portion of an image during video tape recorder trick play operation, the method of prioritizing video data in a data stream comprising the steps of:

• receiving the video data in the video data stream;
• identifying each one of the plurality of data units included in the received video data and the degree of utility of each one of the plurality of data units for generating a recognizable portion of an image during video tape recorder trick play operation, the degree of utility of one of the plurality of data units corresponding to the amount of decrease in the quality of the image portions that can be generated from the video codewords included in the subset of the video data that results when the video data of the one of the plurality of data types is omitted from the subset of the video data, wherein video data of a type required to generate recognizable portions of video images during video tape recorder trick play operation are of a higher degree of utility than data of a type that has little impact on the quality of image portions generated during video tape recorder trick play operation;
• assigning each one of the identified video data units to one of a plurality of N trick play data priority levels as a function of the degree of utility of the identified video data unit being assigned, each one of the N priority levels representing video data units having approximately the same degree of utility for generating a recognizable portion of an image during video tape recorder trick play operation, wherein N is an integer greater than two and;
• outputting a priority level signal indicating the assigned priority level of each of the identified video data units included in the received video data.

A device for prioritizing digital packetized data including codewords in a digital video data stream having a first data rate, to facilitate the subsequent selection of a subset of the video codewords for inclusion in a reduced rate data stream of video codewords intended for use during video tape recorder trick playback operation, each video codeword including data corresponding to one of a plurality of data types having a degree of utility for generating a recognizable portion of an image during video tape recorder trick play operation, the reduced rate data stream having a second data rate that is lower than the first data rate, the device comprising:

• a trick play data prioritizer for receiving the video data stream including the video codewords, and for prioritizing each of the video codewords in the video data stream according to a preselected prioritization scheme, the preselected prioritization scheme assigning each one of the video codewords in the video data stream to one of a plurality of at least three priority levels according to the degree of utility of the type of data included in each video codeword for video tape recorder trick play operation, wherein the degree of utility of each one of the plurality of data types corresponds to the amount of decrease in the quality of the image portions that can be generated from the video codewords included in the reduced rate data stream that results when the codewords of the one of the plurality of data types is omitted from the reduced rate data stream, wherein data of a type required to generate recognizable portions of video images during video tape recorder trick playback operation are of a higher degree of utility than data of a type that has little impact on the quality of image portions generated during video tape recorder trick playback operation, the trick play data prioritizer including an output for outputting the video codewords and a trick play priority level signal.

A method for encoding video data for use by a digital video tape recorder capable of normal play operation and trick play operation, the method comprising the steps of:

• receiving video data;
• encoding the received video data into a first set of encoded video data intended for use by the digital video tape recorder during normal play operation;
• and
• encoding the received video data into a second set of encoded video data including luminance and chrominance information, that is intended for use by the digital video tape recorder for image reproduction only during video tape recorder trick play operation, said second set of encoded video data including encoded video data that is different from said first set of encoded video data.