Video signal encoded with additional detail information

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

• means for providing an image-representative input video signal having a frequency spectrum including a high frequency band containing information to be encoded and a lower frequency band;
• means 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;
• means for combining said input video signal and said folded video signal to produce a combined video signal;
• means for low pass filtering said combined video signal to provide a filtered combined signal composed of a filtered video signal component and a filtered folded video signal component, said low pass filtering means having a cut-off frequency corresponding to said prescribed folding frequency;
• means for unfolding said filtered folded video signal component around said prescribed folding frequency to produce an unfolded video signal containing frequencies in said high frequency band;
• and
• means for joining said unfolded video signal to said high frequency band of said filtered video signal component to produce an output video signal with the highest frequencies thereof determined primarily by said unfolded video signal.

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

• means for providing an image-representative input video signal having a frequency spectrum including a high frequency band containing information to be encoded, and a lower frequency band;
• means for folding said frequency spectrum of said input video signal around a prescribed folding frequency to provide a folded video signal;
• means for combining said input video signal and said folded video signal to produce a combined video signal;
• means for low pass filtering said combined video signal to provide a filtered combined signal, said low pass filtering means having a cut-off frequency corresponding to said prescribed folding frequency;
• means for unfolding said filtered combined video signal around said prescribed folding frequency to produce an unfolded video signal containing frequency in said high frequency band;
• and
• means for filtering said unfolded video signal to generate an output video signal in which aliases generated by unfolding are suppressed.

Apparatus for processing an analog composite video signal of given bandwidth to generate a reduced-bandwidth signal extending to an uppermost frequency below the frequency range in which the color subcarrier and its chrominance sidebands fall, the reduced bandwidth of said reduced-bandwidth signal being at least half said given bandwidth, said apparatus comprising:

• an analog-to-digital converter for digitizing said composite video signal to generate a digitized composite video signal;
• motion detecting means for detecting when the absolute value of changes between a current television image described by said composite video signal and a preceding television image described by said composite video signal exceed a prescribed value, thereby to generate a motion signal;
• a motion-adaptive digital filter for separating from said digitized composite video signal a luma component thereof, as selected in accordance with said motion signal;
• circuitry operative in the digital domain for folding the portions of the separated luma component of said digitized composite video signal that are above said restricted bandwidth in the direction parallel to scan lines around the uppermost frequency in said restricted bandwidth in the direction parallel to scan lines;
• and
• a first digital-to-analog converter for converting said digitized folded luma signal to an analog folded luma signal.

Apparatus for processing an analog composite video signal of given bandwidth to generate a reduced-bandwidth signal extending to an uppermost frequency below the frequency range in which the color subcarrier and its chrominance sidebands fall, the reduced bandwidth of said reduced-bandwidth signal being at least half said given bandwidth, said apparatus comprising:

• an analog-to-digital converter for digitizing said composite video signal to generate a digitized composite video signal;
• motion detecting means for detecting when the absolute value of changes between a current television image described by said composite video signal and a preceding television image described by said composite video signal exceed a prescribed value, thereby to generate a motion signal;
• a signal spreader for low-pass spatially filtering said motion signal to generate a spread motion signal;
• a motion-adaptive digital filter for separating from said digitized composite video signal a luma component thereof, said motion-adaptive digital filter comprising
• a first digital filter responding to said digitized composite video signal to provide a response from which are removed diagonal high spatial frequencies above half-line-frequency in the direction transversal to scan lines and above said restricted bandwidth in the direction parallel to scan lines,
• a second digital filter responding to said digitized composite video signal to provide a response from which are removed frame-to-frame changes above said restricted bandwidth in the direction parallel to scan lines, and
• a soft switch responding to said spread motion signal for selecting as the separated luma component of said digitized composite video signal primarily the response of said first digital filter as said spread motion signal more strongly indicates presence of motion in said composite video signal and primarily the response of said second digital filter as said spread motion signal more strongly indicates absence of motion in said composite video signal;
• and
• circuitry for folding the portions of the separated luma component of said digitized composite video signal that are above said restricted bandwidth in the direction parallel to scan lines around the uppermost frequency in said restricted bandwidth in the direction parallel to scan lines.

Apparatus for processing an analog composite video signal of given bandwidth to generate a reduced-bandwidth signal extending to an uppermost frequency below the frequency range in which the color subcarrier and its chrominance sidebands fall, the reduced bandwidth of said reduced-bandwidth signal being at least half said given bandwidth, said apparatus comprising:

• an analog-to-digital converter for digitizing said composite video signal to generate a digitized composite video signal;
• a digital filter for separating from said digitized composite video signal a luma component thereof;
• and
• circuitry operative in the digital domain for folding the portions of the separated luma component of said digitized composite video signal that are above said restricted bandwidth in the direction parallel to scan lines around the uppermost frequency in said restricted bandwidth in the direction parallel to scan lines.

Apparatus for processing an analog folded luminance signal folded at a folding frequency, said apparatus comprising:

• an analog-to-digital converter for digitizing said analog folded luminance signal to generate a digitized folded luminance signal;
• a source of a digitized unfolding carrier wave;
• a digital multiplier for multiplying said digitized folded luminance signal by said digitized unfolding carrier wave to generate a digital product signal;
• a digital adder for adding the digital product signal supplied from said digital multiplier to said digitized folded luminance signal to generate a digital sum signal including undesired sidebands of said unfolding carrier wave;
• and
• further digital signal processing circuitry for generating a digital recovered full band luminance signal in response to said digital sum signal, including a digital filter for suppressing said undesired sidebands of said unfolding carrier wave in said digital recovered full band luminance signal.