Method and apparatus for synthesizing a copy protection or content control signal with improved playability of a TV set
AssigneeRovi Solutions Corporation
InventorRonald Quan
Life of this patent
Estimating the term…
Abstract
Playability of a copy protected video signal is improved by reducing the darkening and or venetian blind effects which tend to cause artifacts in a video signal display. To this end, the copy protection signal includes automatic gain control (AGC) signals or pulses in video lines in a portion of the active or viewable video field or frame, wherein the AGC pulses comprise non similar AGC signals from one video line to another video line. The dis-similar AGC pulses may include pulses which are deleted, blanked, attenuated, pulse width modified, modulated, etc. In addition, selected sync pulses may be pulse width, amplitude and or position modified.
Claims31
A method of improving playability of a copy protected video signal by reducing venetian blind darkening effects in the video signal, wherein a copy protection signal includes automatic gain control (AGC) pulses in video lines in a portion of an active or viewable television field or frame, comprising:
- inserting or adding non similar AGC pulses from one video line to another video line, in a back porch region of the video lines in the active or viewable television field or frame, wherein the non similar AGC pulses are positive going pulses whose amplitudes are greater than zero IRE and change in IRE from one video line to a next video line;
- and
- wherein the inserting or adding improves playability in a television set by reducing venetian blind darkening effects when compared with adding back porch AGC pulses in 1/N lines or one our of every N lines in the active television field.
A method of reducing venetian blind darkening effects of a content control video signal in a video display to improve playability of the video signal, comprising:
- programming non similar automatic gain control (AGC) signals in selected video lines of a portion of the content control video signal, including at least two of the non similar AGC signals in video lines residing in a visible or viewable portion of a television field or frame;
- and
- wherein the non similar AGC pulses are positive going pulses in a back porch region of the video lines in an active television field or frame, and whose amplitudes are greater than zero IRE through 100 IRE and change in IRE from one video line to a next video line, and wherein adding the non similar AGC pulses whose amplitudes are greater than zero IRE reduce adding the non similar AGC pulses whose amplitudes are greater than zero IRE reduce venetian blind darkening effects when compared with AGC pulses added in 1/N lines or one out of every N lines in the visible or viewable portion of the active television field or frame.
A method of providing a content control command, wherein a video signal contains non similar automatic gain control (AGC) signals from one video line to another, comprising:
- inserting or adding in a back porch region of the video lines in an active video field or frame the non similar AGC signals with amplitudes that vary from greater than zero IRE through about 100 IRE and change in IRE from one video line to a next video line;
- and
- sensing or reading the non similar AGC signals in a portion of the active video field or frame, wherein the sensing or reading of the AGC signals produces a signal that comprises the content control command, and wherein the non similar AGC signals reduce venetian blind darkening effects on a TV monitor when compared to adding AGC signals in the back porch region in 1/N lines or one out of every N lines in the active video field or frame.
A method of reducing venetian blind darkening effects of a video signal in a video display to improve playability, wherein the video signal includes back porch pulses of constant amplitude in 1/N lines or one out of every N lines within a time interval indicative of an active field portion, comprising:
- providing or synthesizing a copy protection signal or a content control signal which includes back porch pulses of non similar pulse width and or amplitude from one video line to another video line;
- wherein the non similar back porch pulses are in the active field portion and are positive going pulses of greater than zero IRE amplitude and or greater than zero pulse width, which amplitude and or width changes from one video line to the next video line;
- and
- wherein the copy protection signal or content control signal produces the reduced venetian blind darkening effect in the video display when compared to the video signal that has back porch pulses included in 1/N lines in the active field portion.
A method of providing a content control signal, or at least part of a copy protection signal for a video signal, comprising:
- adding or inserting a positive going pulse in a video line back porch region in selected horizontal blanking intervals, wherein the selected horizontal blanking intervals include narrowed or modified sync pulses;
- varying the amplitude, phase, position, and or duration of the positive going pulse from one video line location to another video line location to provide a non similar positive going pulse in the line locations in at least a portion of a viewable area of an active television field;
- wherein the amplitude of the non similar positive going pulse in the hack porch region is greater than zero IRE to about 100 IRE and changes in IRE from one video line to a next video line, and wherein the non similar positive going pulse reduces venetian blind darkening effects on a TV monitor when compared to a content control signal or a copy protection signal, wherein the content control and copy protection signals have AGC pulses added to the back porch region in 1/N lines or one out of every N lines in the viewable area of the active television field.
A method of improving playability of a copy protected video signal by reducing venetian blind darkening effects of the video signal, wherein a copy protection signal includes positive going pulses in video lines of a television field or frame, comprising:
- providing non similar positive going pulses from one video line to another video line in an active television field or frame and in a back porch region of the video lines, to improve playability of the copy protected video signal in a television set;
- and
- wherein the non similar positive going pulses on different video lines have amplitudes greater than zero IRE through about 100 IRE and change in IRE from one video line to a next video line, and wherein the similar positive going pulses reduce venetian blind darkening effects on a TV monitor when compared to a content signals or a copy protection signal, wherein the content control and copy protection signals have AGC pulses added to the back porch region in 1/N lines or one out of every N lines in a viewable area of the active television field or frame.
Dependencies are inferred from the claim text.