Claim 1 of the '878 patent reads:
1. An apparatus for encoding digital video signals, comprising:
a means for receiving a digital video input signal comprising a succession of digital representations related to picture elements making up at least one frame of a video image, the frame comprising a plurality of interlaced fields;
a means for coding groups of digital representations related to frames of picture elements;
a means for coding groups of digital representations related to interlaced fields in the frames; and
a means responsive to the digital video input signal for producing a field frame coding type signal which directs a selected one, but not both, of the frame coding means or the field coding means to code the digital video input signal.
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