| 4599648 |
Video signal transmission systems |
| Jul-8-1986 |
A video signal transmission system wherein a television video signal is subjected to a waveform conversion in a video processing unit on a transmission side, then sent to a receiving side and restored... |
| 5060262 |
Video scrambling, audio masking and data transmission methods for wireless cable systems |
| Oct-22-1991 |
Video scrambling is accomplished by attenuating the video carrier during the horizontal blanking interval and/or by omitting horizontal sync pulses, vertical serration pulses and equalizing pulses. The... |
| 4742545 |
Video picture signal scrambling system |
| May-3-1988 |
A video picture signal scrambling system for subscription braodcast or cablecast television systems which can scramble video signals without adversely effecting pictures received at a subscriber's terminal.... |
| 4598318 |
Video encryption system |
| Jul-1-1986 |
An encrypted video distribution system includes a signal-originating head end for scrambling outgoing television program-bearing signals. In particular, the video content of selected lines is inverted... |
| 4257065 |
Video clamp and inverter circuit |
| Mar-17-1981 |
A high performance video clamp and self-balancing inverter circuit for providing the DC coupling of a video signal together with substantially perfect inversion of any portion of a composite television... |
| 4429331 |
Video cipher processing system |
| Jan-31-1984 |
A video cipher processing system comprising a detecting means for detecting average tone variation of TV video signals, an extracting means for extracting at random at least some of outputs from the detecting... |
| 4024574 |
Validation method and apparatus for pay television systems |
| May-17-1977 |
A predetermined pattern of code signals is periodically inserted into the transmitted encoded television signal. The pattern is so chosen that a bistable circuit at the receiver changes state for each... |
| 4022972 |
Transient suppression and grey level coincidence in a subscription television system |
| May-10-1977 |
Due to unavoidable timing and slope errors in the leading and trailing edges of invert pulses utilized in encoding and decoding of the television signal by inversion of the picture signal portion relative... |
| 4308556 |
Television video signal scrambling system |
| Dec-29-1981 |
A video signal scrambling system for use with a pay television system in which video signals are scrambled so that only specified subscribers can receive the program. Inversion of the video signal level... |
| 4679235 |
Television signal transmission system |
| Jul-7-1987 |
A television signal transmission system transmits a television signal having a polarity inverted portion in association with a scene change and a polarity inverted portion after a predetermined time interval... |
| 4463376 |
Television signal processing system for a wireless pay system |
| Jul-31-1984 |
A television signal processing system characterized in that a level of at least a portion of a blanking interval of a coded television signal is shifted towards a white level and falling of the level shifting... |
| 4307416 |
Television signal modification apparatus |
| Dec-22-1981 |
Apparatus is disclosed which modifies a video signal (in the video frequency range) for scrambling (encoding) and unscrambling (decoding) video signals for television pictures. |
| 4628358 |
Television signal encryption system with protected audio |
| Dec-9-1986 |
An encrypted video distribution system includes a signal-originating head end for scrambling the audio portion of outgoing television program-bearing signals. In particular, the audio content of a television... |
| 4759061 |
Technique for toggling coding mode in a television signal encoder |
| Jul-19-1988 |
A technique for toggling the coding mode in a television signal encoder comprises establishing a rectangular window defining a relatively small and substantially centrally located portion of the field... |
| 5185794 |
System and method for scrambling and/or descrambling a video signal |
| Feb-9-1993 |
An audiovisual subscription system includes means for aperiodically inverting the lines of a transmitted video signal on a frame-by-frame basis and for decrypting encrypted PCM audio information which... |
| 4215366 |
Subscriber-limited reception television broadcast security encoder-decoder system |
| Jul-29-1980 |
A method and apparatus for encoding and decoding of standard television signals are provided for enabling reception thereof in an intelligible manner only by authorized subscribers. The scrambling of the... |
| 4387393 |
Signal unscrambler |
| Jun-7-1983 |
A received video signal that has been inverted at the transmitter is reinverted by the use of low cost pin diodes to reverse the ground and signal lead connections to the primary winding of a transformer... |
| 3996418 |
Scrambler and decoder for secure television system |
| Dec-7-1976 |
A scrambler for a television system alternately inverts the phase of the carrier which is modulated by the television signal. A binary coding signal controls the manner of the carrier-phase inversion.... |
| 3936593 |
Scrambler and decoder for a television signal |
| Feb-3-1976 |
An improved scrambler and decoder for a television signal is described wherein a television carrier is inverted in phase and subjected to low frequency amplitude modulation to obtain enhanced channel security.... |
| 4447828 |
Phase change dynamic scrambling |
| May-8-1984 |
A means for coding and decoding video signals by the application of one of a plurality of available scrambling signals, which scrambling signals have a common frequency but differ in phase, includes means... |
| 4245246 |
Pay TV system |
| Jan-13-1981 |
An apparatus for coding video information arranged in a plurality of lines comprises means for selectively inverting video information in groups of lines. A random timing device controls the number of... |
| 6971012 |
Motion picture electronic watermark system |
| Nov-29-2005 |
To provide an electronic watermark method and system for which the detection reliability of embedded information does not depend on the strength of signals that are measured in frames. To achieve the above... |
| 4613902 |
Method of broadcasting an encoded video signal and a receiving apparatus for decoding the signal |
| Sep-23-1986 |
A video signal is encoded prior to broadcasting by inverting portions of the signal about an encoding axis at a predetermined reference level. To enable the reference level to be determined accurately... |
| 4045814 |
Method and apparatus for scrambling and unscrambling communication signals |
| Aug-30-1977 |
Method and apparatus for scrambling and unscrambling television video and audio signals in a subscription television system in which program selections of subscribers are known at a central transmitting... |
| 4024576 |
Method and apparatus for scrambling and unscrambling communication signals |
| May-17-1977 |
Method and apparatus for scrambling and unscrambling television video and audio signals in a subscription television system in which program selections of subscribers are known at a central transmitting... |
| 4019201 |
Method and apparatus for scrambling and unscrambling communication signals |
| Apr-19-1977 |
Method and apparatus for scrambling and unscrambling television video and audio signals in a subscription television system in which program selections of subscribers are known at a central transmitting... |
| 5491748 |
Enhanced security for a cable system |
| Feb-13-1996 |
A cable television plant scrambling system incorporates video inversion with a pair of mode signals included in the vertical blanking interval of a scrambled television signal for identifying the proper... |
| 6771794 |
Electronic watermark generating apparatus, electronic watermark generating method and memory medium therefor |
| Aug-3-2004 |
In a situation where a data portion is considered as of higher importance in the course of preparation of original data, the designer is enabled to set the electronic watermark in a position that is judged... |
| 4454543 |
Dynamic video scrambling |
| Jun-12-1984 |
A means for coding and decoding video signals by the application of one of a plurality of available scrambling signals includes means for comparing the brightness level during a predetermined time period... |
| 4389671 |
Digitally-controlled analog encrypton |
| Jun-21-1983 |
An apparatus for scrambling a television signal in which horizontal lines of the transmitted television picture are selectively inverted in accordance with the state of a pseudorandom noise generator.... |
| 4091417 |
Decoder mode validation apparatus for pay television systems |
| May-23-1978 |
A predetermined pattern of code signals is periodically inserted into the transmitted encoded television signal. The pattern is so chosen that a bistable circuit at the receiver changes state for each... |
| 6510229 |
Communication system with multicarrier telephony transport |
| Jan-21-2003 |
A communication system for transferring digital data over a distribution network is described. The communication system includes an interface for receiving successive strings of digital data from a source,... |
| 4025948 |
Coding system for pay television apparatus |
| May-24-1977 |
At the sending end, a plurality of high-frequency oscillators each furnish a signal having a frequency different from the frequency of the other of the oscillators. Timing signals derived from the television... |
| 4369462 |
Coding system for pay television |
| Jan-18-1983 |
A coding system for use in a television system wherein at least a part of a television signal is inverted by an encoder at a broadcasting station, according to a code signal and the coded television signal... |
| 4471379 |
Codified field polarity television system |
| Sep-11-1984 |
There is disclosed herein a television system wherein television signals are scrambled or otherwise encoded at the transmitting facility and then unscrambled or decoded at the receiving facility, typically... |
| 4336554 |
Code signal blanking apparatus |
| Jun-22-1982 |
A code signal blanking apparatus comprising a switching means operative during a given period of a vertical blanking period of a television signal and a reference level setting means for producing an output... |
| 4700388 |
Apparatus for scrambling a television signal |
| Oct-13-1987 |
An apparatus for scrambling or encoding a television signal by inverting the latter signal in accordance with a control signal having a predetermined code pattern comprises a detector circuit for detecting... |
| 5848154 |
Apparatus for managing software using quantity |
| Dec-8-1998 |
A DES decrypting unit decrypts video data frames encrypted and compressed based on MPEG standards, when receiving them. The decrypted video data frames are expanded one by one in a MPEG expansion circuit.... |
| 4635113 |
Apparatus for descrambling transmitted scrambled television signals |
| Jan-6-1987 |
This invention relates to an apparatus for descrambling scrambled television signals including a scrambled video signal having a first scrambling pattern, a scrambled control signal having a second scrambling... |
