Method and Apparatus for Inducing and or Reducing Geometric Distortions in a Display via Positive Going Pulses
AssigneeRovi Technologies Corporation
InventorRonald Quan
Life of this patent
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Abstract
In certain flat screen TV sets, such as LCD monitors, geometric errors can be induced in a video signal by positive going pulses. That is, a shift in a display is provided when one or more positive going pulse is added to the video signal following one or more sync pulse. To illustrate, AGC pulses, generally used for content control and or copy protection in the last lines of an active video field, cause a shift (horizontal displacement) in the picture for these last lines in the active field. Alternatively, turning off or attenuating such positive going pulses in the last lines of the active field, eliminates or reduces the picture shift.
Claims9
Method of inducing geometric distortion in a display of a video signal on a video monitor, wherein the video signal includes video lines with horizontal (and vertical) sync pulses, comprising:
- adding or inserting one or more positive going pulse following respective one or more sync pulse in selected video lines of the display, to cause a horizontal displacement in the selected video lines of the display, which displacement defines the geometric distortion.
Method of controlling or defeating the amount of geometric distortion caused by the addition of positive going pulses in a portion of an active field of a video signal, comprising:
- attenuating or removing one or more of the positive going pulses in the portion of the active field.
Dependencies are inferred from the claim text.