US 4,277,796 A · Slow down color processor for video disc mastering using a special mode VTR

Abstract

Selected fields of a redundant field slow motion video tape reproduced video signal are stored in a memory at a given clock rate and recovered at a lower clock rate that is inversely proportional to the number of times each field is repeated so as to produce a non-redundant video signal of reduced bandwidth. An audio signal is simultaneously reproduced from the tape at a rate less than that at which it was originally recorded and combined with the recovered video signal to produce a composite audio-video signal of reduced bandwidth possessing the full informational content of the original audio and video signals. The composite signal is suitable for application to the cutterhead of a video disc mastering lathe operating at reduced turntable speed whereby full bandwidth master recordings may be made with a cutterhead of lesser bandwidth.

Claims11

Dependent claims

A slow down processor for producing a composite audio-video signal of reduced bandwidth suitable for use in mastering of video disc records at less than real time rates, said processor comprising:

tape recorder means responsive in a playback mode for producing a redundant field video signal, each field being produced at a rate corresponding to the rate at which it was originally recorded on said tape, and responsive also in said playback mode for producing an audio signal from the tape at a rate less than the original recording rate of said audio signal;
memory means for providing temporary storage of selected fields of said redundant field video signal;
memory control means responsive to a field identification signal supplied thereto for writing said selected fields into said memory means at a given clock rate proportional to a subcarrier reference signal supplied thereto and for reading and selected fields out of said memory means at a lesser clock rate so as to produce a non-redundant video output signal of reduced bandwidth, the ratio of said clock rates being predetermined in accordance with the redundancy level of said redundant field video signal;
and
means for combining said audio signal with said non-redundant video signal produced by said memory means to provide said composite signal.

2 more elements

A slow down processor for producing a composite FM audio FM video signal of reduced bandwidth suitable for use in mastering of video disc records at 1/Nth real time rate wherein N is an integer greater than unity, said processor comprising:

slow motion magnetic tape recorder means responsive in a playback mode for producing an audio signal from a magnetic video tape, the audio reproduce head-to-tape velocity being equal to 1/Nth of its original recording value whereby the bandwidth of said audio signal is reduced by a factor 1/N, said recorder being responsive also in said playback mode for producing a redundant field video signal, the video reproduce head-to-tape velocity being equal to its original recording value whereby the bandwidth of said video signal equals its original value, each redundant set of fields including N similar fields;
digital memory means for providing temporary storage of a selected field from each said set of fields, each one of said selected fields being a member of a subset conforming in terms of field sequence and chrominance phase to a predetermined broadcasting standard;
memory control means responsive to a field identification signal supplied thereto for writing said selected fields into said memory means at a given clock rate f.sub.c, and for reading said selected fields out of said memory means at a lesser clock rate equal to f.sub.c /N for producing a nonredundant video output signal of reduced bandwidth conforming in terms of field sequence and chrominance phase to said predetermined broadcasting standard;
and
FM modulator and combiner means responsive to said audio signal produced by said tape recorder means and said non-redundant video output signal read from said memory means for producing said composite FM audio FM video signal.

2 more elements

Dependencies are inferred from the claim text.

Slow down color processor for video disc mastering using a special mode VTR

Life of this patent

Slow down color processor for video disc mastering using a special mode VTR

Life of this patent

Abstract

Claims11