Video signal encoded with additional detail information

A system for processing video signals, comprising:

• a source of an input video signal representative of successive image frames, said input video signal having a frequency spectrum including a high frequency band containing information to be encoded and a lower frequency band;
• circuitry responsive to spatially localized frame-to-frame changes in said input video signal for generating a motion signal having a first state indicating substantial frame-to-frame change in said input video signal and having a second state indicating insubstantial frame-to-frame change in said input video signal;
• a first motion-adaptive filter for generating a first motion-adaptive filter response to said input video signal, as controlled by said motion signal, which first motion-adaptive filter response has a frequency spectrum including a low frequency subspectrum below a folding frequency and including a high frequency subspectrum above said folding frequency, said high frequency subspectrum containing information to be encoded;
• spectrum-folding circuitry for folding said frequency spectrum of said first motion-adaptive filter response around said folding frequency and lowpass filtering the result to provide a folded video signal, said folded video signal including an image spectrum generated in response to said high frequency subspectrum, which image subspectrum overlaps a portion of said low frequency subspectrum;
• a transmission medium through which said motion signal and said folded video signal are transmitted, to supply a transmitted folded video signal and a transmitted motion signal;
• spectrum-unfolding circuitry for unfolding said transmitted folded video signal to produce an unfolded video signal, reproducing said high frequency subspectrum from said image subspectrum;
• and
• a second motion-adaptive filter for generating a second motion-adaptive filter response that reproduces said input video signal, as controlled by said transmitted motion signal, said second motion-adaptive filter performing adaptive spatial filtering on said unfolded video signal when said transmitted motion signal indicates said first state of said motion signal gave rise to said unfolded video signal currently supplied said second motion-adaptive filter, and said second motion-adaptive filter performing temporal low pass filtering on said unfolded video signal when said transmitted motion signal indicates said second state of said motion signal gave rise to said unfolded video signal currently supplied said second motion-adaptive filter.

In a system for processing a television-type signal, apparatus for processing high-frequency video information comprising:

• a source of input video signal having a frequency spectrum including a high frequency band and a lower frequency band;
• circuitry for folding said frequency spectrum of said input video signal around a prescribed folding frequency in said lower frequency band to provide a folded video signal;
• circuitry for combining said input video signal and said folded video signal to produce a combined video signal;
• and
• a horizontal lowpass filter for low pass filtering said combined video signal to provide a filtered signal, said horizontal lowpass filter having a cut-off frequency corresponding to said prescribed folding frequency.

Apparatus for decoding a folded-frequency-spectrum television-type video signal with a first component occupying upper and lower frequency bands, said upper frequency band containing an encoded second component generated by folding of the frequency spectrum of said video signal extending beyond a prescribed frequency, said prescribed frequency being within said upper frequency band and near the upper edge thereof, said apparatus comprising:

• a first filter connected for responding to said received television-type video signal to provide a filtered video signal, said first filter having a cut-off at said prescribed frequency and supplying said filtered video signal as a response to components of said received television-type video signal that are below said cut-off in frequency;
• a second filter connected for receiving said filtered video signal, said second filter providing a selective response to only those components of said filtered video signal within said upper frequency band;
• a mixer of multiplicative type for multiplying said selective response of said second filter to said upper frequency band by a reference carrier signal of said prescribed frequency, said mixer connected as spectrum unfolding circuitry for generating a product output signal in which the frequency spectrum of said encoded second component is unfolded around said prescribed frequency;
• and
• circuitry for combining the unfolded second component in the product signal of said multiplier with said first component of said filtered video signal in said first filter response to produce an output video signal with the highest frequencies thereof determined primarily by the frequency spectrum of said unfolded second component.

Apparatus for decoding a folded-frequency-spectrum television-type video signal with a first component occupying upper and lower frequency bands, said upper frequency band containing an encoded second component generated by folding of the frequency spectrum of said video signal extending beyond a prescribed frequency, said prescribed frequency being within said upper frequency band and near the upper edge thereof, said apparatus comprising:

• a first filter connected for responding to said received television-type video signal to provide a filtered video signal, said first filter having a cut-off at said prescribed frequency and supplying said filtered video signal as a response to components of said received television-type video signal that are below said cut-off in frequency;
• a second filter connected for receiving said filtered video signal, said second filter providing a selective response to only those components of said filtered video signal within said upper frequency band;
• a mixer of multiplicative type for multiplying said selective response of said second filter to said upper frequency band by a reference carrier signal of said prescribed frequency, said mixer connected as spectrum unfolding circuitry for generating a product output signal in which the frequency spectrum of said encoded second component is unfolded around said prescribed frequency;
• and
• circuitry for combining the unfolded second component in the product signal of said multiplier with said first component of said received television-type video signal to produce an output video signal with the highest frequencies thereof determined primarily by the frequency spectrum of said unfolded second component.