Abstract: Method and apparatus for scrambling a high definition television signal to discourage unauthorized recording of same. While recording per se is not prevented, the resulting recorded signal is rendered unusable due to an induced “wobble” between the active video and the associated sync pulses. The scrambled television signal is readily viewable on a compliant high definition television set which descrambles the HDTV signal using an encoded indication of the amount of wobble accompanying the HDTV signal. Also provided is a special interface to prevent unauthorized persons from using the indication of the amount of wobble so as to defeat the scrambling. Also provided are method and apparatus for defeating the scrambling method and hence allowing recording of the scrambled video signal.

Abstract: A method and apparatus for modifying a video signal to allow it to carry encoded data which is detectable at a suitably compliant receiver but is not recorded by a conventional video recorder. One application is to carry a descrambling key to prevent useful recording (but not viewing) of a scrambled television signal since the key will not be recorded. This encoded “hidden” data is not recorded by the conventional video recorders because, for instance, it is located in the vertical or horizontal blanking intervals of the video signal, or is carried by a high frequency carrier signal, or is expressed by phase modulation of the video signal's synchronization pulses.

Abstract: Method and apparatus for scrambling a high definition television signal to discourage unauthorized recording of same. While recording per se is not prevented, the resulting recorded signal is rendered unusable due to an induced “wobble” between the active video and the associated sync pulses. The scrambled television signal is readily viewable on a compliant high definition television set which descrambles the HDTV signal using an encoded indication of the amount of wobble accompanying the HDTV signal. Also provided is a special interface to prevent unauthorized persons from using the indication of the amount of wobble so as to defeat the scrambling. Also provided are method and apparatus for defeating the scrambling method and hence allowing recording of the scrambled video signal.

Abstract: In typical prior art generational copy protection processes, a video tag signal is added to a watermarked and/or copy protected video signal to prevent the production of unauthorized second generation copies and the playback of illicit second generation copies. This application discloses a means for defeating the tag signal/watermark copy protection process. To this end, various embodiments are disclosed by which the tag signal is recovered, converted to a selected tag representation and is carried or stored in some manner, concurrently with the recording of a first generation copy of the video signal, which may or may not be tagless. The first generation copy is played back and the tag representation is converted to a regenerated tag signal which is selectively re-inserted in the reproduction of the first generation copy prior to recording a second generation copy, which now is playable.

Abstract: Method and apparatus for scrambling a high definition television signal to discourage unauthorized recording of same. While recording per se is not prevented, the resulting recorded signal is rendered unusable due to an induced “wobble” between the active video and the associated sync pulses. The scrambled television signal is readily viewable on a compliant high definition television set which descrambles the HDTV signal using an encoded indication of the amount of wobble accompanying the HDTV signal. Also provided is a special interface to prevent unauthorized persons from using the indication of the amount of wobble so as to defeat the scrambling. Also provided are method and apparatus for defeating the scrambling method and hence allowing recording of the scrambled video signal.

Abstract: A video-scrambling system induces a random wobble i.e., time shifting, in the location of active portion of the video frame, without affecting the horizontal sync signal and colorburst in each video line, thus providing both security and concealment. The security is enhanced by filling in the gap between the nominal beginning of active video and the actual beginning of active video with a synthesized video signal which replicates the adjacent active video using a digitally generated filling pattern. Also, a random noise overlay further conceals the location of the gap. Additional concealment is provided by wiggling in time the location of the horizontal sync signal using one or two frequencies and also by randomly altering the location of the vertical sync signal. The NTSC digital encoding in accordance with the invention is simplified by using only two channels, chrominance and luminance, and by a heterodyne circuit for chrominance stability.

Abstract: A video-scrambling system induces a random wobble i.e., time shifting, in the location of active portion of the video frame, without affecting the horizontal sync signal and colorburst in each video line, thus providing both security and concealment. The security is enhanced by filling in the gap between the nominal beginning of active video and the actual beginning of active video with a synthesized video signal which replicates the adjacent active video using a digitally generated filling pattern. Also, a random noise overlay further conceals the location of the gap. Additional concealment is provided by wiggling in time the location of the horizontal sync signal using one or two frequencies and also by randomly altering the location of the vertical sync signal. The NTSC digital encoding in accordance with the invention is simplified by using only two channels, chrominance and luminance, and by a heterodyne circuit for chrominance stability.

Abstract: A video-scrambling system induces a random wobble i.e., time shifting, in the location of active portion of the video frame, without affecting the horizontal sync signal and colorburst in each video line, thus providing both security and concealment. The security is enhanced by filling in the gap between the nominal beginning of active video and the actual beginning of active video with a synthesized video signal which replicates the adjacent active video using a digitally generated filling pattern. Also, a random noise overlay further conceals the location of the gap. Additional concealment is provided by wiggling in time the location of the horizontal sync signal using one or two frequencies and also by randomly altering the location of the vertical sync signal. The NTSC digital encoding in accordance with the invention is simplified by using only two channels, chrominance and luminance, and by a heterodyne circuit for chrominance stability.

Abstract: A video-scrambling system induces a random wobble i.e., time shifting, in the location of active portion of the video frame, without affecting the horizontal sync signal and colorburst in each video line, thus providing both security and concealment. The security is enhanced by filling in the gap between the nominal beginning of active video and the actual beginning of active video with a synthesized video signal which replicates the adjacent active video using a digitally generated filling pattern. Also, a random noise overlay further conceals the location of the gap. Additional concealment is provided by wiggling in time the location of the horizontal sync signal using one or two frequencies and also by randomly altering the location of the vertical sync signal. The NTSC digital encoding in accordance with the invention is simplified by using only two channels, chrominance and luminance, and by a heterodyne circuit for chrominance stability.

Abstract: A video-scrambling system induces a random wobble i.e., time shifting, in the location of active portion of the video frame, without affecting the horizontal sync signal and colorburst in each video line, thus providing both security and concealment. The security is enhanced by filling in the gap between the nominal beginning of active video and the actual beginning of active video with a synthesized video signal which replicates the adjacent active video using a digitally generated filling pattern. Also, a random noise overlay further conceals the location of the gap. Additional concealment is provided by wiggling in time the location of the horizontal sync signal using one or two frequencies and also by randomly altering the location of the vertical sync signal. The NTSC digital encoding in accordance with the invention is simplified by using only two channels, chrominance and luminance, and by a heterodyne circuit for chrominance stability.

Abstract: A video-scrambling system induces a random wobble i.e., time shifting, in the location of active portion of the video frame, without affecting the horizontal sync signal and colorburst in each video line, thus providing both security and concealment. The security is enhanced by filling in the gap between the nominal beginning of active video and the actual beginning of active video with a synthesized video signal which replicates the adjacent active video using a digitally generated filling pattern. Also, a random noise overlay further conceals the location of the gap. Additional concealment is provided by wiggling in time the location of the horizontal sync signal using one or two frequencies and also by randomly altering the location of the vertical sync signal. The NTSC digital encoding in accordance with the invention is simplified by using only two channels, chrominance and luminance, and by a heterodyne circuit for chrominance stability.

Abstract: A video-scrambling system induces a random wobble i.e., time shifting, in the location of active portion of the video frame, without affecting the horizontal sync signal and colorburst in each video line, thus providing both security and concealment. The security is enhanced by filling in the gap between the nominal beginning of active video and the actual beginning of active video with a synthesized video signal which replicates the adjacent active video using a digitally generated filling pattern. Also, a random noise overlay further conceals the location of the gap. Additional concealment is provided by wiggling in time the location of the horizontal sync signal using one or two frequencies and also by randomly altering the location of the vertical sync signal. The NTSC digital encoding in accordance with the invention is simplified by using only two channels, chrominance and luminance, and by a heterodyne circuit for chrominance stability.

Abstract: Vertical-rate and horizontal-rate sawtooth generators are coupled at a common input to a conventional focus control voltage and then to the centering circuits of an image tube via respective potentiometers. The amplitudes and polarities of the generator outputs are selected such that when driven simultaneously by the electrical focus control voltage supplied to an image tube, generates an image rotation which just cancels any image rotational error inherently induced by an electrical focus adjustment.

Abstract: A vertical-rate sawtooth waveform amplitude modulates a train of horizontal-rate pulses. Positive and negative pulse clippers receive the pulse train. One generates a clipped waveform during the last half and a zero output for the first half, of a television field. The other generates a clipped waveform during the first half and a zero output the last half of the field. A pair of AC coupled integrators, driven by respective clipped waveforms, generate horizontal-rate sawtooths which are linearly modulated, one from a maximum at the beginning of the field to zero at the center thereof, and one from zero at the center to a maximum at the end of the field. Two pairs of clippers separate the two sawtooths into four half-sawtooths, wherein each is active in a time interval corresponding to respective quadrants of the picture raster. Potentiometers are used to vary the respective waveforms to allow independent correction of the scan in any corner.

Abstract: A simplified automatic error correction setup system is coupled to the remote control multiplex/demultiplex circuitry in a color camera to generate and store respective error correction control voltages for selected operating parameters during a camera setup mode, with subsequent automatic retrieval of the stored error correction control voltages during camera operation. The automatic control voltages are digitally generated from incoming error signals via a control system loop generally formed of an error selector switch, a digital register, a digital-to-analog converter (DAC) and a random access memory (RAM). The register and/or RAM data are converted to analog control voltages via the DAC for each parameter (i.e., channel) being automatically corrected, which voltages are linearly summed with the corresponding control voltages. During the automatic setup mode, the RAM contents are updated via the register for any existing errors in the specific operating parameters.

Abstract: Precise, point-by-point correction of spatial and shading errors in a camera television picture are performed manually. The errors to be corrected are determined by visually examining a picture on a video monitor, by selecting an area for error correction which area corresponds to the type and extent of the specific error selected for correction. A position command increments or decrements an address by preselected steps to locate a movable "cursor" which, in turn, identifies the area being corrected. A correction command retrieves the data from the area identified, and which contains the error, selectively increments or decrements the data in preselected steps, and stores the new data back in memory. The process continues until the operator is satisfied with the correction results. Correction thus may be made point-by-point, along horizontal or vertical lines or areas, in selected corner areas, etc., of the picture.