Resources Contact Us Home
Method and apparatus for optimizing scrambling concealment of a video signal by modifying a specialized sync pulse

Image Number 7 for United States Patent #6009172.

A technique for improving the scrambling concealment of a video signal and the like when displayed on a television set or monitor, includes the pulse width and/or pulse position modulation of a horizontal sync pulse in a horizontal blanking interval by time shifting the leading edge of the sync pulse while maintaining the trailing edge thereof stationary, by shifting the leading and/or trailing edge of the pulse, or by position modulating a sync pulse of specialized width. In modifications to the pulse width and pulse position modulation overlay techniques, the negative edge of the end of video lines may be modulated in the same way that the leading edge of the sync pulse is modulated, with the two edges locked together or modulated independently. Thus, the amount of position modulation of the horizontal sync pulse or its edge(s) is maximized so that the pertinent circuits of all television sets will always detect, and thus lock onto, the modulated or wobbling pulse width or pulse position modulated sync pulse. The embodiment in which the negative edges of the ends of video lines are modulated along with the sync pulses, insures that all television sets will lock onto a wobbling edge. This insures the concealment of the video signal, or equivalent signal, in all possible situations and for all types of television sets or monitors. An associated technique also is disclosed for descrambling the scrambled video signal when authorized.

  Recently Added Patents
Viruses lacking epithelial cell receptor entry
Flexible lighting devices
Digital photographing apparatus and control method for evaluating validity of an auto-focus operation
Electronic component mounting machine and operating instruction method for the same
Method of manufacturing a plurality of electronic assemblies
Verification of a portable consumer device in an offline environment
Security arrangements for extended USB protocol stack of a USB host system
  Randomly Featured Patents
Method for purifying bidentate organophosphorus compounds
Modular cache memory battery backup system
Systems and methods for robotic gutter cleaning along an axis of rotation
High power factor boost rectifier apparatus
Device for applying and distributing shaving foam on the face
Process for the production of a (1R,Cis)-4 acetyl-6,6-dimethyl-3-oxabicyclo-(3.1.0.)-hex-2-one
Optical cross-connect apparatus
RFID system and method for protecting information
Peptides for treating axonal damage, inhibition of neurotransmitter release and pain transmission, and blocking calcium influx in neurons
Graphic user interface for a portion of a display screen