Patent US4594609A successfully refreshed from Google Patents.
US4594609A
Expired / Lapsed
US
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Scrambling system for television video signal
Assignee: GSW Inc
•
Filing: 1983-06-30
•
Granted: 1986-06-10
•
Expires: 2003-06-30
Abstract
Abstract A method and apparatus for scrambling a composite television signal and method and apparatus for unscrambling of the scrambled television signal are disclosed in the present application. The method of scrambling shifts at least some lines of video information relative to adjacent (preceding or subsequent) lines of video information according to a predetermined scheme, and deletes at least some portions of the signal which comprise synchronization or control information of a known or predetermined repetitive form from between at least some of the adjacent shifted lines of video information. The method of unscrambling applies a complementary shift to return the video information into proper time spacing and includes the insertion of any necessary synchronization information eliminated from the signal during scrambling. Timing information allows the unscrambler to reverse the scrambling operation and thereafter insert any necessary synchronization information. This scrambling technique maitaining at least essentially all of the video information thereby allowing faithful reproduction on a television. The system in addition to being secure, is compatible with communication channels used to distribute television signals and the apparatus for unscrambling the signal is relatively inexpensive and reliable.
Inventors
- 👤 Nuno Romao
- 👤 Ivica Mudrinic
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 18:12
CPC Classifications
H; H04; H04N; H04N7/00; H04N7/16; H04N7/167; H04N7/169; H04N7/1696; H04N7/171; H04N7/1713
Claims Analysis
Total Claims: 165
Claim 1
Independent Claim
56 words
A method of scrambling a composite television video signal having intervals containing video information separated by horizontal synchronization pulses the method comprising shifting in time according to a predetermined scheme at least some portions of the composite television signal in a manner to eliminate at least some horizontal synchronization pulses between adjacent intervals containing video information.
Claim 2
Independent Claim
56 words
A method of scrambling a composite television video signal having intervals containing video information separated by horizontal synchronization pulses the method comprising shifting in time according to a predetermined scheme at least some portions of the composite television signal in a manner to eliminate at least some horizontal synchronization pulses between adjacent intervals containing video information.
Claim 3
Dependent Claim
36 words
A method of scrambling a composite television video signal as claimed in claim 1 wherein at least some adjacent intervals containing video information in the scrambled television signal are separated by a time duration of zero.
Claim 4
Dependent Claim
40 words
A method of scrambling a composite television video signal as claimed in claim 1 wherein the minimum amount of time a portion is shifted essentially equals the duration separating the intervals containing video information of the composite television video signal.
Claim 5
Dependent Claim
42 words
A method of scrambling a composite television video signal as claimed in claim 1 wherein the minimum amount of time a portion is shifted essentially equals the duration of a front porch and a horizontal synchronization pulse of the composite television signal.
Claim 6
Dependent Claim
33 words
A method of scrambling a composite television video signal as claimed in claim 4 wherein each amount of time a portion is shifted is an integer multiple of said minimum amount of time.
Claim 7
Dependent Claim
35 words
A method of scrambling a composite television video signal as claimed in claim 1 including periodically inserting into said scrambled television signal a control signal indicative of said predetermined scheme and periodically providing timing information.
Claim 8
Dependent Claim
38 words
A method of scrambling a composite television video signal as claimed in claim 1 wherein said step of shifting is controlled to introduce from time to time extraneous video information between adjacent video information in the scrambled signal.
Claim 9
Dependent Claim
69 words
A method of scrambling a composite television video signal having vertical blanking intervals separating the intervals containing video information as claimed in claim 1 wherein said step of shifting is controlled such that a number of horizontal synchronization pulses precede and a number of horizontal synchronization pulses follow each vertical blanking interval and the time duration thereof remains unchanged for use by a receiver in unscrambling of the signal.
Claim 10
Independent Claim
185 words
A method for scrambling a composite television video signal having a sequence of intervals containing video information separated by intervals containing horizontal synchronization information necessary for reception by a television of a predetermined or known repetitive form, the method comprising processing the composite television signal to provide a scrambled television signal containing essentially all the video information of the composite television signal and omitting at least some of the horizontal synchronization information of the composite television signal necessary for reception, wherein at least some of the intervals containing video information in said scrambled television signal are separated by intervals having a duration less than the duration of the intervals separating the intervals containing video information of the composite television signal, wherein said processing is accomplished by shifting in time according to a predetermined scheme at least some portions of the composite television signal, and wherein said step of shifting is controlled to allow said scrambled television signal to be subsequently processed to provide a signal substantially corresponding to the composite television signal by creating and inserting any necessary horizontal synchronization information that has been omitted.
Claim 11
Independent Claim
185 words
A method for scrambling a composite television video signal having a sequence of intervals containing video information separated by intervals containing horizontal synchronization information necessary for reception by a television of a predetermined or known repetitive form, the method comprising processing the composite television signal to provide a scrambled television signal containing essentially all the video information of the composite television signal and omitting at least some of the horizontal synchronization information of the composite television signal necessary for reception, wherein at least some of the intervals containing video information in said scrambled television signal are separated by intervals having a duration less than the duration of the intervals separating the intervals containing video information of the composite television signal, wherein said processing is accomplished by shifting in time according to a predetermined scheme at least some portions of the composite television signal, and wherein said step of shifting is controlled to allow said scrambled television signal to be subsequently processed to provide a signal substantially corresponding to the composite television signal by creating and inserting any necessary horizontal synchronization information that has been omitted.
Claim 12
Dependent Claim
86 words
A method for scrambling a composite television video signal as claimed in claim 9, wherein said processing comprises producing from the composite television signal at least one signal corresponding to the composite television signal and having a time shift relative to the composite television signal of a duration at least substantially equal to the duration of a horizontal synchronization pulse, successively selecting according to said predetermined scheme one of the composite television signals and said at least one corresponding signal to produce said scrambled television signal.
Claim 13
Dependent Claim
53 words
A method for scrambling a composite video signal as claimed in claim 10 wherein the maximum time difference between each of said selected signals and at least another selected signal is less than or essentially equal to the duration of the intervals separating the intervals containing video information of the composite television signal.
Claim 14
Dependent Claim
36 words
A method for scrambling a composite television video signal as claimed in claim 10 wherein the time differences between the duration of each of said selected signals and at least another selected signal are essentially equal.
Claim 15
Dependent Claim
36 words
A method for scrambling a composite television video signal as claimed in claim 12 wherein said time difference is equal to the duration of a front porch and horizontal synchronization pulse of the composite television signal.
Claim 16
Dependent Claim
22 words
A method for scrambling a composite television video signal as claimed in claim 13 wherein said time difference equals approximately 6.35 microseconds.
Claim 17
Dependent Claim
46 words
A method for scrambling a composite television video signal as claimed in claim 10 wherein said step of selecting is controlled such that essentially any interval containing video information is derived from only one of the composite television signal and said at least one produced signal.
Claim 18
Dependent Claim
57 words
A method for scrambling a composite television video signal as claimed in claim 10 wherein essentially all the steps of selecting are controlled such that no signal is selected which is advanced in time relative to the prior selected signal by an amount greater than the duration separating intervals containing video information in the composite television signal.
Claim 19
Dependent Claim
58 words
A method for scrambling a composite television video signal as claimed in claim 10 wherein the time average of the durations of the intervals separating the intervals containing video information in said scrambled signal approach the time average of the duration of the intervals separating intervals containing video information in the composite television signal as time approaches infinity.
Claim 20
Dependent Claim
64 words
A method for scrambling a composite television video signal as claimed in claim 9 wherein the sum of the duration of the intervals separating the intervals containing video information in the scrambled television signal essentially equal the sum of the duration of the intervals separating the intervals containing video information in the composite television signal for any particular field of the composite television signal.
Claim 21
Dependent Claim
40 words
A method for scrambling a composite television video signal as claimed in claim 10 wherein essentially each line of video information in the scrambled television signal is shifted relative to the corresponding line of video information in the predecessor field.
Claim 22
Dependent Claim
32 words
A method for scrambling a composite television video signal as claimed in claim 10 wherein said at least one signal is produced by passing the composite television video signal through delay means.
Claim 23
Dependent Claim
25 words
A method for scrambling a composite television video signal as claimed in claim 20 wherein said delay means comprise digitally controlled analogue shift register means.
Claim 24
Dependent Claim
27 words
A method for scrambling a composite television video signal as claimed in claim 21 wherein said analogue shift register means comprise at least one charge coupled device.
Claim 25
Dependent Claim
39 words
A method for scrambling a composite television video signal as claimed in claim 21 wherein said analogue shift register means comprise an analogue to digital signal converter, a digital shift register means and a digital to analogue signal converter.
Claim 26
Dependent Claim
57 words
A method for scrambling a composite television video signal as claimed in claim 20 wherein said delay means are cascaded and tapped at at least one junction thereof and the termination thereof to provide at least two signals corresponding to the composite television signal and having at least two time shifts relative to the composite television signal.
Claim 27
Dependent Claim
35 words
A method for scrambling a composite television video signal as claimed in claim 22 wherein said at least one charge coupled device has 91 elements and is clocked at a frequency of approximately 14.31 MHz.
Claim 28
Dependent Claim
38 words
A method for scrambling a composite television video signal as claimed in claim 10 wherein said step of successively selecting is performed by single-pole single-throw electronic switches having one pole of each switch electrically connected to one another.
Claim 29
Dependent Claim
26 words
A method for scrambling a composite television video signal as claimed in claim 9 wherein said synchronization information necessary for reception comprises a horizontal synchronization pulse.
Claim 30
Dependent Claim
29 words
A method for scrambling a composite television video signal as claimed in claim 10 wherein said step of selecting is controlled such that no horizontal synchronization information is selected.
Claim 31
Dependent Claim
39 words
A method for scrambling a composite television video signal as claimed in claim 28 wherein following the end of each interval containing video information in said scrambled television signal a different signal is selected for a period of time.
Claim 32
Dependent Claim
38 words
A method for scrambling a composite television video signal as claimed in claim 29 wherein said period of time is greater than or essentially equal to the duration separating intervals containing video information in the composite television signal.
Claim 33
Dependent Claim
35 words
A method for scrambling a composite television video signal as claimed in claim 29 wherein said period of time is essentially equal to the duration separating intervals containing video information in the composite television signal.
Claim 34
Dependent Claim
34 words
A method for scrambling a composite television video signal as claimed in claim 31 wherein multiple selections of signals are made following the end of an interval containing video information of the selected signal.
Claim 35
Dependent Claim
37 words
A method for scrambling a composite television video signal as claimed in claim 28 wherein a signal containing digital data is selected at the end of at least some intervals containing video information of the selected signal.
Claim 36
Dependent Claim
65 words
A method for scrambling a composite television video has vertical blanking intervals separating such sequence of video information signal as claimed in claim 10 wherein said step of selecting is controlled such that said scrambled television signal contains only intervals containing video information of the composite television signal and portions of the intervals containing video information of the composite television signal between vertical blanking intervals.
Claim 37
Dependent Claim
27 words
A method for scrambling a composite television video signal as claimed in claim 34 wherein said portions comprise leading and trailing portions of intervals containing video information.
Claim 38
Dependent Claim
66 words
A method for scrambling a composite television video signal as claimed in claim 9 wherein the maximum duration of any said interval separating intervals containing video information in said scrambled television signal essentially equals the maximum time difference between each of said selected signals and the composite television signal plus the duration of the intervals separating the intervals containing video information in the composite television signal.
Claim 39
Dependent Claim
70 words
A method for scrambling a composite television video signal as claimed in claim 9 wherein said processing comprises passing the composite television signal according to said predetermined scheme through shifting means having at least two channels with at least one non-zero time shift value greater than or equal to the duration of a horizontal synchronization pulse and combining the signals output from said channels to produce said scrambled television signal.
Claim 40
Dependent Claim
32 words
A method for scrambling a composite television video signal as claimed in claim 37 wherein said shifting means has a zero time shift value and at least one non-zero time shift value.
Claim 41
Dependent Claim
68 words
A method for scrambling a composite television video signal as claimed in claim 37 wherein the time at which the composite television signal is passed to a channel of said shifting means for shifting by a non-zero amount of time preceeds the time at which said shifted signal is to be combined to produce said scrambled television signal by a duration equal to said non-zero amount of time.
Claim 42
Dependent Claim
29 words
A method for scrambling a composite television video signal as claimed in claim 37 wherein only one signal from said channels at any time effects said scrambled television signal.
Claim 43
Dependent Claim
84 words
A method for scrambling a composite television video signal as claimed in claim 37 wherein the composite television signal is passed to at least two channels of said shifting means for shifting by two different amounts of time simultaneously for a period of time when the duration of an interval separating intervals containing video information in said scrambled television signal is to be made greater than or equal to the duration of the intervals separating intervals containing video information in the composite television signal.
Claim 44
Dependent Claim
42 words
A method for scrambling a composite television video signal as claimed in claim 41 wherein said period of time equals the amount by which the duration of the interval in said scrambled television signal separating intervals containing video information is made greater.
Claim 45
Dependent Claim
70 words
A method for scrambling a composite television video signal as claimed in claim 37 wherein no composite television signal is passed to any channel of said shifting means for a period of time when the duration of an interval separating intervals containing video information in said scrambled television signal is to be made less than the duration of the intervals separating intervals containing video information in the composite television signal.
Claim 46
Dependent Claim
42 words
A method for scrambling a composite television video signal as claimed in claim 43 wherein said period of time equals the amount by which the duration of the interval separating intervals containing video information in said scrambled television signal is made less.
Claim 47
Dependent Claim
47 words
A method for scrambling a composite television video signal as claimed in claim 37 wherein the order of the sequence of lines of video information in said scrambled television signal essentially equals the order of the sequence of lines of video information in the composite television signal.
Claim 48
Independent Claim
194 words
A method for scrambling a composite television video signal having a sequence of augmented picture portions including a back porch and a line of video information separated by intervals having a front porch and a horizontal synchronization pulse, the method comprising processing the composite television signal to produce a scrambled television signal containing essentially all the augmented picture portions of the composite television signal and omitting at least some of the horizontal synchronization pulses of the composite television signal, wherein at least some of the augmented picture portions in said scrambled television signal are separated by intervals having a duration less than the duration of the intervals separating the augmented picture portions of the composite television signal, wherein said processing is accomplished by shifting in time according to a predetermined scheme at least some portions of the augmented picture portions of the composite television signal, wherein said step of shifting is controlled to allow said scrambled television signal to be subsequently processed to provide a signal substantially corresponding to the composite television video signal by shifting of the video information and creating and inserting the necessary synchronization information omitted during scrambling of the signal.
Claim 49
Independent Claim
194 words
A method for scrambling a composite television video signal having a sequence of augmented picture portions including a back porch and a line of video information separated by intervals having a front porch and a horizontal synchronization pulse, the method comprising processing the composite television signal to produce a scrambled television signal containing essentially all the augmented picture portions of the composite television signal and omitting at least some of the horizontal synchronization pulses of the composite television signal, wherein at least some of the augmented picture portions in said scrambled television signal are separated by intervals having a duration less than the duration of the intervals separating the augmented picture portions of the composite television signal, wherein said processing is accomplished by shifting in time according to a predetermined scheme at least some portions of the augmented picture portions of the composite television signal, wherein said step of shifting is controlled to allow said scrambled television signal to be subsequently processed to provide a signal substantially corresponding to the composite television video signal by shifting of the video information and creating and inserting the necessary synchronization information omitted during scrambling of the signal.
Claim 50
Dependent Claim
91 words
A method for scrambling a composite television video signal as claimed in claim 46 wherein said processing comprises producing from the composite television signal at least one signal corresponding to the composite television signal and having a time shift relative to the composite television signal of a duration at least substantially equal to the duration of a horizontal synchronization pulse, successively selecting according to said predetermined scheme one of the composite television signal and said at least one corresponding signal and combining said selected signals to produce said scrambled television signal.
Claim 51
Dependent Claim
37 words
A method for scrambling a composite television video signal as claimed in claim 46 wherein the augmented picture portions include a colour burst portion and said scrambled television signal contains essentially all of said colour burst portions.
Claim 52
Dependent Claim
45 words
A method for scrambling a composite television video signal as claimed in claim 46 wherein the augmented picture portions include a colour burst portion and wherein essentially all the back porches and colour burst portions in said scrambled signal are shifted to a grey level.
Claim 53
Dependent Claim
52 words
A method for scrambling a composite television video signal as claimed in claim 47 wherein said step of selecting is controlled such that the time of essentially all changes to another selected signal occurs outside the time period in which an augmented picture portion in said scrambled television signal is being derived.
Claim 54
Dependent Claim
125 words
A method for scrambling a composite television video signal as claimed in claim 47 wherein said step of selecting is controlled such that no portion of the composite television signal and said at least one corresponding signal containing a front porch and a horizontal synchronization pulse is selected and following the end of an augmented picture portion of the selected signal a different signal is selected for a period of time and wherein said period of time is equal to the sum of the duration of a front porch and a horizontal synchronization pulse of the composite television signal when the next following signal containing an augmented picture portion is the same as said prior selected signal containing said end of the augmented picture portion.
Claim 55
Independent Claim
283 words
A method for scrambling a composite colour television video signal having a plurality of fields containing a sequence of augmented picture portions of fixed duration consisting of a back porch followed by a colour burst portion followed by a line of video information and separated by intervals of fixed duration consisting of a front porch and a horizontal synchronization pulse, the method comprising selecting according to a predetermined scheme either the composite television signal or a corresponding version thereof delayed in time relative to the composite television signal by a duration essentially equal to the sum of the duration of the front porch and the horizontal synchronization pulse and combining said selected signals to form a scrambled television signal containing essentially all of the augmented picture portions of the composite television signal, wherein essentially all of the front porches and horizontal synchronization pulses of the composite television signal are omitted in said scrambled television signal, wherein some adjacent augmented picture portions in said scrambled television signal are separated by intervals having a duration of zero and some adjacent augmented picture portions in said scrambled television signal are separated by intervals having a duration essentially equal to the sum of the duration of a front porch and a horizontal synchronization pulse and the remaining adjacent augmented picture portions in said scrambled television signal are separated by intervals having a duration essentially equal to two times the sum of the duration of a front porch and a horizontal synchronization pulse, and wherein essentially all of the intervals of duration other than zero separating adjacent augmented picture portions in said scrambled television signal consist of portions of the augmented picture portions of the composite television signal.
Claim 56
Independent Claim
283 words
A method for scrambling a composite colour television video signal having a plurality of fields containing a sequence of augmented picture portions of fixed duration consisting of a back porch followed by a colour burst portion followed by a line of video information and separated by intervals of fixed duration consisting of a front porch and a horizontal synchronization pulse, the method comprising selecting according to a predetermined scheme either the composite television signal or a corresponding version thereof delayed in time relative to the composite television signal by a duration essentially equal to the sum of the duration of the front porch and the horizontal synchronization pulse and combining said selected signals to form a scrambled television signal containing essentially all of the augmented picture portions of the composite television signal, wherein essentially all of the front porches and horizontal synchronization pulses of the composite television signal are omitted in said scrambled television signal, wherein some adjacent augmented picture portions in said scrambled television signal are separated by intervals having a duration of zero and some adjacent augmented picture portions in said scrambled television signal are separated by intervals having a duration essentially equal to the sum of the duration of a front porch and a horizontal synchronization pulse and the remaining adjacent augmented picture portions in said scrambled television signal are separated by intervals having a duration essentially equal to two times the sum of the duration of a front porch and a horizontal synchronization pulse, and wherein essentially all of the intervals of duration other than zero separating adjacent augmented picture portions in said scrambled television signal consist of portions of the augmented picture portions of the composite television signal.
Claim 57
Independent Claim
162 words
A method of scrambling a composite television video signal having vertical blanking intervals separated by a sequence of lines of video information which are separated by horizontal synchronization intervals each containing a horizontal synchronization pulse, said method comprising shifting in time according to a predetermined scheme to decrease the time duration between at least some portions of the composite signal by an amount at least equal to the duration of a horizontal synchronization pulse and in a manner to eliminate at least some horizontal synchronization pulses, said shifting being controlled such that essentially any shifted portions contain complete lines of video information and no overlap of lines of video information in the scrambled signal occurs, whereby the scrambled signal requires the shifting of at least some of the lines of video information to re-establish the time duration between adjacent video portions to that as essentially found in the composite signal to allow insertion of any necessary horizontal synchronization pulses to effect unscrambling.
Claim 58
Independent Claim
162 words
A method of scrambling a composite television video signal having vertical blanking intervals separated by a sequence of lines of video information which are separated by horizontal synchronization intervals each containing a horizontal synchronization pulse, said method comprising shifting in time according to a predetermined scheme to decrease the time duration between at least some portions of the composite signal by an amount at least equal to the duration of a horizontal synchronization pulse and in a manner to eliminate at least some horizontal synchronization pulses, said shifting being controlled such that essentially any shifted portions contain complete lines of video information and no overlap of lines of video information in the scrambled signal occurs, whereby the scrambled signal requires the shifting of at least some of the lines of video information to re-establish the time duration between adjacent video portions to that as essentially found in the composite signal to allow insertion of any necessary horizontal synchronization pulses to effect unscrambling.
Claim 59
Dependent Claim
77 words
A method of scrambling a composite television video signal as claimed in claim 53 wherein said shifting is accomplished by selectively passing the composite signal through at least one time delay means to produce the scrambled signal having at least some portions thereof shifted in time and wherein the maximum time shift of any line of video information relative to another line of video information is less than the time duration of one line of video information.
Claim 60
Dependent Claim
39 words
A method of scrambling a composite television video signal as claimed in claim 53 including introducing extraneous video information in place of at least some of the horizontal synchronization pulses uneffected by the shifting of lines of video information.
Claim 61
Dependent Claim
38 words
A method of scrambling a composite television video signal as claimed in claim 53 wherein the time duration between adjacent vertical blanking intervals in the scrambled signal is the same as that found in the composite television signal.
Claim 62
Dependent Claim
54 words
A method of scrambling a composite television video signal as claimed in claim 53 wherein the scrambled signal has a number of horizontal synchronization pulses preceding and following each vertical blanking interval having the same time relation as found in the composite signal to provide timing information used during the unscrambling of the signal.
Claim 63
Dependent Claim
48 words
A method of scrambling a composite television video signal as claimed in claim 53 including from time to time inserting digital data into the scrambled signal for portions of the composite signal which need not be transmitted to allow essentially faithful reproduction of the composite signal upon unscrambling.
Claim 64
Dependent Claim
34 words
A method of scrambling a composite television video signal as claimed in claim 53 including inserting a control signal in the scrambled signal indicative of the predetermined scheme of scrambling and the commencement thereof.
Claim 65
Dependent Claim
67 words
A method of scrambling a composite television video signal as claimed in claim 53 wherein said step of shifting is controlled to provide a time shift between a line of information on one side of a vertical blanking interval and the generally corresponding lines of video information on the other side of such vertical blanking interval which cooperate to produce the image produced on a television screen.
Claim 66
Independent Claim
81 words
A method of scrambling a composite television video signal having intervals containing video information separated by horizontal synchronization pulses the method comprising processing the composite signal to effect removal of the horizontal synchronization pulses from between at least some of the adjacent video information and to shift such adjacent video information relative to each other to at least decrease the time duration therebetween such that video information at least occupies the space from which a horizontal synchronization pulse has been removed.
Claim 67
Independent Claim
81 words
A method of scrambling a composite television video signal having intervals containing video information separated by horizontal synchronization pulses the method comprising processing the composite signal to effect removal of the horizontal synchronization pulses from between at least some of the adjacent video information and to shift such adjacent video information relative to each other to at least decrease the time duration therebetween such that video information at least occupies the space from which a horizontal synchronization pulse has been removed.
Claim 68
Dependent Claim
56 words
A method of scrambling a composite television video signal according to claim 61, wherein the processing of the composite signal includes passing the composite signal on occasion according to a predetermined scheme through time delay means to produce portions of the scrambled signal generally corresponding to the composite signal and having a time shift relative thereto.
Claim 69
Dependent Claim
64 words
A method of scrambling a composite television video signal according to claim 62, wherein said predetermined scheme is such that the time shift between a portion of the scrambled signal delayed relative to an adjacent following portion is less than or equal to the time duration of a synchronization pulse and front porch and greater than the time duration of a horizontal synchronization pulse.
Claim 70
Dependent Claim
41 words
A method of scrambling a composite television video signal as claimed in claim 61 wherein said processing of the composite signal introduces from time to time extraneous video information in place of the signal which would otherwise separate adjacent video information.
Claim 71
Dependent Claim
65 words
A method of scrambling a composite television video signal as claimed in claim 61 wherein the processing of the signal includes passing the signal through time delay means which shift the signal in time approximately 6.35 micro seconds where upon switch from a delayed mode to a mode advanced in time results in the elimination of a portion of the signal between adjacent video information.
Claim 72
Independent Claim
87 words
A method of scrambling a composite television video signal having intervals containing video information separated by horizontal synchronization pulses, the method comprising processing the composite signal to shift according to a predetermined scheme at least some adjacent video information to at least decrease the time duration therebetween by an amount at least substantially equal to the duration of a horizontal synchronization pulse by eliminating a portion of the signal which need not be transmitted to allow at least substantially faithful reproduction of the composite signal upon unscrambling.
Claim 73
Independent Claim
87 words
A method of scrambling a composite television video signal having intervals containing video information separated by horizontal synchronization pulses, the method comprising processing the composite signal to shift according to a predetermined scheme at least some adjacent video information to at least decrease the time duration therebetween by an amount at least substantially equal to the duration of a horizontal synchronization pulse by eliminating a portion of the signal which need not be transmitted to allow at least substantially faithful reproduction of the composite signal upon unscrambling.
Claim 74
Dependent Claim
47 words
A method of scrambling a composite television video signal as claimed in claim 66, wherein the eliminated portion includes a horizontal synchronization pulse which due to its predetermined or known repetitive form can be created and inserted in accordance with timing information during unscrambling of the signal.
Claim 75
Dependent Claim
48 words
A method of scrambling a composite television video signal as claimed in claim 66, wherein horizontal synchronization pulses and associated front porches are eliminated which due to their predetermined or known repetitive form can be created and inserted in accordance with timing information during unscrambling of the signal.
Claim 76
Dependent Claim
27 words
A method of scrambling a composite television video signal as claimed in claim 66, wherein the eliminated portion includes the trailing edge of the preceding video information.
Claim 77
Dependent Claim
44 words
A method of scrambling a composite television video signal as claimed in claim 66, wherein the eliminated portion is selected from the group consisting of trailing edge of preceding video information, front porch, the horizontal synchronization pulse, the back porch and a colour burst.
Claim 78
Dependent Claim
33 words
A method of scrambling a composite television video signal as claimed in claim 67 including replacing the portion of the signal between at least some of the video information with extraneous video information.
Claim 79
Dependent Claim
49 words
A method of scrambling a composite television video signal as claimed in claim 67 wherein said processing of said composite signal effects elimination of at least some horizontal synchronization pulses and replaces the portion of the signal between at least some of the video information with extraneous video information.
Claim 80
Dependent Claim
69 words
A method of scrambling a composite television video signal having vertical blanking intervals separating the intervals containing video information as claimed in claim 66 wherein said step of shifting is controlled such that a number of horizontal synchronization pulses precede and a number of horizontal synchronization pulses follow each vertical blanking interval and the time duration thereof remains unchanged for use by a receiver in unscrambling of the signal.
Claim 81
Independent Claim
164 words
An apparatus for unscrambling a scrambled television signal scrambled by eliminating at least some necessary horizontal synchronization information of a predetermined or known repetitive form between adjacent intervals of video information and having at least some intervals of video information shifted according to a predetermined scheme and in a manner to decrease the time duration between at least some adjacent intervals of video information said apparatus comprising means for receiving a scrambled television signal, means for receiving timing information associated with such scrambled signal, means for shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal and means for creating and inserting in accordance with the timing information synchronization information eliminated during scrambling to produce an unscrambled signal substantially faithful relative to the original composite signal.
Claim 82
Independent Claim
164 words
An apparatus for unscrambling a scrambled television signal scrambled by eliminating at least some necessary horizontal synchronization information of a predetermined or known repetitive form between adjacent intervals of video information and having at least some intervals of video information shifted according to a predetermined scheme and in a manner to decrease the time duration between at least some adjacent intervals of video information said apparatus comprising means for receiving a scrambled television signal, means for receiving timing information associated with such scrambled signal, means for shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal and means for creating and inserting in accordance with the timing information synchronization information eliminated during scrambling to produce an unscrambled signal substantially faithful relative to the original composite signal.
Claim 83
Dependent Claim
19 words
An apparatus as claimed in claim 74 wherein said creating and inserting means create and insert horizontal synchronization pulses.
Claim 84
Dependent Claim
46 words
An apparatus as claimed in claim 74 wherein said means for creating and inserting in accordance with the timing information create and insert front porches and horizontal synchronization pulses preceding lines of video information to produce an unscrambled signal essentially corresponding to the original unscrambled signal.
Claim 85
Dependent Claim
50 words
An apparatus as claimed in claim 74 wherein the scrambled television signal has portion thereof which have not been scrambled and wherein said means for receiving timing information comprises means for detecting and locking onto the horizontal synchronization information in the portions of the signal which have not been scrambled.
Claim 86
Dependent Claim
53 words
An apparatus as claimed in claim 77 wherein said means for detecting horizontal synchronization information controls a time base generator for determining the time at which horizontal synchronization information is to be inserted into the unscrambled television signal and the time at which portions of the scrambled television signal are to be shifted.
Claim 87
Dependent Claim
44 words
An apparatus as claimed in claim 74 wherein the scrambled television signal is accompanied by a modulated audio signal and wherein the scrambled television signal is passed through a demodulator to produce a base band scrambled television signal void of a modulated audio signal.
Claim 88
Dependent Claim
24 words
An apparatus as claimed in claim 79 wherein the base band scrambled television signal is unscrambled and subsequently recombined with the modulated audio signal.
Claim 89
Dependent Claim
26 words
An apparatus as claimed in claim 74 wherein said shifting means is cascaded with a gain amplifier to compensate for gain variations in said shifting means.
Claim 90
Dependent Claim
27 words
An apparatus as claimed in claim 81 including feedback balancing means to compensate for any DC bias level offset in said shifting means and said gain amplifier.
Claim 91
Dependent Claim
79 words
An apparatus as claimed in claim 82 including means for periodically injecting a reference signal into the scrambled television signal, sample and hold means for detecting the reference signal and shifted portions thereof, differential amplifier means for detecting any differences between the reference signal and shifted portions thereof and bias level altering means cascaded with said shifting means and responsive to said differential amplifier means to drive the difference between the reference signal and shifted portions thereof towards zero.
Claim 92
Dependent Claim
45 words
An apparatus as claimed in claim 83 wherein said sample and hold means comprise a double pole electronic switch with each of the switched poles being connected to a capacitor for holding the voltages established thereon upon the closing of said double pole electronic switch.
Claim 93
Dependent Claim
29 words
An apparatus as claimed in claim 84 wherein said differential amplifier means has a large gain value and is phase compensated to prevent oscillations in the feedback balancing means.
Claim 94
Dependent Claim
18 words
An apparatus as claimed in claim 85 wherein said feedback balancing means operates in a negative feedback mode.
Claim 95
Dependent Claim
33 words
An apparatus as claimed in claim 74 wherein there is encoded in or associated with the scrambled television signal digital information and including means for extracting digital information in the scrambled television signal.
Claim 96
Dependent Claim
32 words
An apparatus as claimed in claim 87 wherein said means for extracting digital information in responsive to abrupt transitions in the scrambled television signal between the white level and the black level.
Claim 97
Dependent Claim
36 words
An apparatus as claimed in claim 87 wherein said digital information contains information indicative of the predetermined scheme of scrambling and said means for extracting digital information extracts information indicative of the predetermined scheme of scrambling.
Claim 98
Dependent Claim
56 words
An apparatus as claimed in claim 87 wherein said digital information contains information indicative of the predetermined scheme of scrambling and addressing information for determining if the unscrambler is authorized to unscramble the television signal and wherein said means for extracting digital information extracts the information indicative of the predetermined scheme of scrambling and addressing information.
Claim 99
Dependent Claim
76 words
An apparatus as claimed in claim 87 wherein said digital information is encoded in the last full interval which would normally contain video information immediately preceding the vertical blanking interval and an interval in the vertical blanking interval and wherein said means for extracting digital information is responsive to only information in the last full interval which would normally contain video information immediately preceding the vertical blanking interval and an interval in the vertical blanking interval.
Claim 100
Dependent Claim
74 words
An apparatus as claimed in claim 87 wherein said digital information contains addressing information for determining if the unscrambler is authorized to unscramble the television signal and including static register means for holding information uniquely identifying said unscrambler, and comparing means, whereby the addressing information is compared with the information held in the static register means for determining a match thereby allowing the unscrambler to recognize further addressing information specific to the identified scrambler.
Claim 101
Dependent Claim
17 words
An apparatus as claimed in claim 92 wherein said means for enabling said unscrambler comprises a microprocessor.
Claim 102
Dependent Claim
38 words
An apparatus as claimed in claim 74 including means for determining if said received signal is not scrambled and means for bypassing said shifting means responsive to said means for determining if said received signal is not scrambled.
Claim 103
Dependent Claim
39 words
An apparatus as claimed in claim 74 including a pseudo random number generator responsive to received signals indicative of the predetermined scheme of scrambling to produce an output signal for controlling shifting of portions of the scrambled television signal.
Claim 104
Dependent Claim
22 words
An apparatus as claimed in claim 95 wherein said pseudo random number generator is an algorithm implemented in a suitably programmed microprocessor.
Claim 105
Dependent Claim
28 words
An apparatus as claimed in claim 74 wherein said means for producing horizontal synchronization information is a two level controlled voltage source responsive to said received timing information.
Claim 106
Dependent Claim
55 words
An apparatus as claimed in claim 97 wherein one level of said controlled voltage source corresponds to the voltage level of a front porch in a composite television signal and the other level of said control voltage source corresponds to the level of the tip of a horizontal synchronization pulse in a composite television signal.
Claim 107
Dependent Claim
28 words
An apparatus as claimed in claim 98 wherein said two level controlled voltage source has an output which is combined with shifted portions of the scrambled television signal.
Claim 108
Dependent Claim
47 words
An apparatus as claimed in claim 99 wherein there is a brief overlapping period of time in which the voltage delivered by the controlled voltage source and the shifted portions of the scrambled television signal are combined to prevent switching transients appearing in the unscrambled television signal.
Claim 109
Dependent Claim
95 words
An apparatus as claimed in claim 100 wherein the two level controlled voltage source is controlled to provide a first voltage level corresponding to the level of a front porch in a composite television signal at the time at which the front porch would appear in a composite television signal and is controlled to provide a second voltage level corresponding to the level of the tip of a horizontal synchronization pulse in a composite television signal at the time at which the tip of a horizontal synchronization pulse would appear in a composite television signal.
Claim 110
Dependent Claim
18 words
An apparatus as claimed in claim 74 wherein said shifting means comprise digitally controlled analogue shift register means.
Claim 111
Dependent Claim
34 words
An apparatus as claimed in claim 102 wherein said digitally controlled analogue shift register means comprise at least one charge coupled device having 91 elements and clocked at a frequency of approximately 14.31 MHz.
Claim 112
Dependent Claim
62 words
An apparatus as claimed in claim 74 wherein said shifting means comprises delay means to produce at least one signal corresponding to the scrambled television signal and having a time shift relative thereto and selecting means for selecting according to a scheme determined by the predetermined scheme of scrambling one of the scrambled television signal and said at least one corresponding signal.
Claim 113
Dependent Claim
38 words
An apparatus as claimed in claim 104 wherein said selecting means comprises an electronic multiple pole switch having each switched pole thereof electrically connected to one of the scrambled television signal and said at least one corresponding signal.
Claim 114
Independent Claim
140 words
An apparatus for unscrambling a scrambled television signal wherein a number of lines of video information have been shifted according to a predetermined scheme to decrease the time duration between at least some adjacent lines of video information by an amount at least equal to the duration of a horizontal synchronization pulse, said apparatus comprising means for receiving a scrambled television signal, means for receiving timing information associated with such scrambled signal, means for shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal and means for creating and inserting in accordance with the timing information horizontal synchronization information eliminated during scrambling.
Claim 115
Independent Claim
140 words
An apparatus for unscrambling a scrambled television signal wherein a number of lines of video information have been shifted according to a predetermined scheme to decrease the time duration between at least some adjacent lines of video information by an amount at least equal to the duration of a horizontal synchronization pulse, said apparatus comprising means for receiving a scrambled television signal, means for receiving timing information associated with such scrambled signal, means for shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal and means for creating and inserting in accordance with the timing information horizontal synchronization information eliminated during scrambling.
Claim 116
Dependent Claim
24 words
An apparatus as claimed in claim 106 including means for creating and inserting in accordance with the timing information any necessary horizontal synchronization pulses.
Claim 117
Dependent Claim
39 words
An apparatus as claimed in claim 106 including means for creating and inserting in accordance with the timing information horizontal synchronization pulses preceding lines of video information to produce an unscrambled signal generally corresponding to the original unscrambled signal.
Claim 118
Independent Claim
132 words
A method of unscrambling a scrambled composite television video signal wherein a number of lines of video information have been shifted according to a predetermined scheme to decrease the time duration between at least some adjacent lines of video information by an amount at least equal to the duration of a horizontal synchronization pulse thereby eliminating a substantial portion of the signal between adjacent lines of video information, said method comprising receiving such scrambled television signal, receiving timing information associated with such scrambled signal, shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal.
Claim 119
Independent Claim
132 words
A method of unscrambling a scrambled composite television video signal wherein a number of lines of video information have been shifted according to a predetermined scheme to decrease the time duration between at least some adjacent lines of video information by an amount at least equal to the duration of a horizontal synchronization pulse thereby eliminating a substantial portion of the signal between adjacent lines of video information, said method comprising receiving such scrambled television signal, receiving timing information associated with such scrambled signal, shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal.
Claim 120
Dependent Claim
48 words
A method of unscrambling a scrambled television signal as claimed in claim 109 wherein the scrambled signal has at least some horizontal synchronization pulses eliminated, said method including creating and inserting in accordance with the timing information any necessary horizontal synchronization pulses between adjacent lines of video information.
Claim 121
Dependent Claim
79 words
A method of unscrambling a scrambled television signal as claimed in claim 110 wherein said shifting is accomplished by selectively processing according to the scheme determined by the predetermined scheme various portions of the scrambled signal through time delay means whereby the unscrambled signal is delayed in time relative to the original signal by an amount greater than or equal to the maximum period any interval in the composite television signal was shifted to produce the scrambled television signal.
Claim 122
Dependent Claim
59 words
A method of unscrambling a scrambled television as claimed in claim 110 wherein each interval containing video information in the scrambled television signal is shifted by an amount equal to a fixed amount of time less the actual period of time the interval containing video information in the composite television signal was shifted to produce the scrambled television signal.
Claim 123
Dependent Claim
48 words
A method of unscrambling a scrambled television signal having periodically injected accurate frequencies therein as claimed in claim 110 wherein timing information is received by detecting the accurate frequencies to provide a time base to control the time at which portions of the scrambled television signal are shifted.
Claim 124
Dependent Claim
52 words
A method of unscrambling a scrambled television signal having periodically injected control signals indicative of the scheme in which the scrambled television signal was scrambled as claimed in claim 109 including receiving said periodically injected control signals and deriving therefrom the scheme in which portions of the scrambled television signal are shifted.
Claim 125
Dependent Claim
47 words
A method of unscrambling as claimed in claim 110 wherein the scrambled signal has predetermined portions thereof which have not been scrambled to thereby encode timing information in the scrambled signal, such that timing information is obtained during unscrambling by detecting and locking onto the predetermined portions.
Claim 126
Dependent Claim
42 words
A method of unscrambling as claimed in claim 110 wherein said received television signal is accompanied by a modulated audio signal, said method including demodulating the received signal to produce a base band scrambled television signal void of a modulated audio signal.
Claim 127
Dependent Claim
33 words
A method of unscrambling as claimed in claim 110 wherein said shifting is accomplished by selectively processing the signal through time delay means and compensating for gain variations of the time delay means.
Claim 128
Dependent Claim
30 words
A method as claimed in claim 117 including providing a feedback balancing signal to compensate for any D.C. bias level offset caused by the shifting and the gain variation compensation.
Claim 129
Dependent Claim
59 words
A method as claimed in claim 118 including periodically injecting a reference signal into the scrambled television signal, sampling and holding the reference signal and shifted positions thereof, detecting any differences between the reference signal and shifted portions thereof and altering the bias level of at least one of the detected signals to drive the detected differences towards zero.
Claim 130
Dependent Claim
46 words
A method of unscrambling as claimed in claim 119 wherein said sampling and holding includes a double pole electronic switch with each of said switch poles being connected to a capacitor for holding the voltages established thereon upon the closing of said double pole electronic switch.
Claim 131
Dependent Claim
165 words
In a scrambled television transmission system having a transmitting end at least one receiving end, a method of scrambling a composite television video signal having lines containing video information separated by horizontal synchronization pulses, said method of scrambling shifting in time according to a predetermined scheme at least some portions of the composite television signal in a manner to eliminate at least some horizontal synchronization pulses between adjacent lines of video information, in combination with a method of unscrambling by said at least one receiver, said method of unscrambling comprising receiving such scrambled television signal, receiving timing information associated with such scrambled signal, shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the composite television signal and creating and inserting at least any necessary horizontal synchronization information eliminated during scrambling.
Claim 132
Dependent Claim
165 words
In a scrambled television transmission system having a transmitting end at least one receiving end, a method of scrambling a composite television video signal having lines containing video information separated by horizontal synchronization pulses, said method of scrambling shifting in time according to a predetermined scheme at least some portions of the composite television signal in a manner to eliminate at least some horizontal synchronization pulses between adjacent lines of video information, in combination with a method of unscrambling by said at least one receiver, said method of unscrambling comprising receiving such scrambled television signal, receiving timing information associated with such scrambled signal, shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the composite television signal and creating and inserting at least any necessary horizontal synchronization information eliminated during scrambling.
Claim 133
Dependent Claim
166 words
In a television transmission system which transmits a scrambled composite television video signal, a scrambler for scrambling a composite television signal for transmission and an unscrambler for receiving and unscrambling the scrambled signal, the composite signal having lines of video information separated by horizontal synchronization pulses, said scrambler comprising means for shifting in time some portions of the composite signal, and control means for controlling said shifting means according to a predetermined scheme to produce a scrambled television signal wherein at least some horizontal synchronization pulses between adjacent intervals containing video information have been eliminated while maintaining substantially all of the video information, said unscrambler comprising means for receiving timing information associated with such scrambled signal, means for shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal.
Claim 134
Dependent Claim
166 words
In a television transmission system which transmits a scrambled composite television video signal, a scrambler for scrambling a composite television signal for transmission and an unscrambler for receiving and unscrambling the scrambled signal, the composite signal having lines of video information separated by horizontal synchronization pulses, said scrambler comprising means for shifting in time some portions of the composite signal, and control means for controlling said shifting means according to a predetermined scheme to produce a scrambled television signal wherein at least some horizontal synchronization pulses between adjacent intervals containing video information have been eliminated while maintaining substantially all of the video information, said unscrambler comprising means for receiving timing information associated with such scrambled signal, means for shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal.
Claim 135
Dependent Claim
29 words
In a television transmission system as claimed in claim 122 wherein said unscrambler includes means for creating and inserting in accordance with timing information any necessary horizontal synchronization pulses.
Claim 136
Independent Claim
202 words
A method of scrambling a composite television video signal having fields with each field having a vertical blanking interval followed by a sequence of lines of video information separated by a front porch, a horizontal synchronization pulse, a back porch and a colour burst portion associated with a given line of video information, said method comprising selectively delaying within a given field portions of the composite television signal by at least one time delay unit equal to or less than the sum of the durations of a front porch, a horizontal synchronization pulse and a back porch and each portion that is delayed including at least one colour burst portion and the associated line of video information to produce a scrambled signal wherein at least some of the horizontal synchronization pulses present in the composite television signal have been eliminated as a result of selectively delaying portions of the signal and the time duration between at least some other lines of adjacent video information has been increased, while maintaining at least substantially all of the lines of video information and associated colour burst portions and the vertical blanking interval, and including timing information to used during the unscrambling of the scrambled signal.
Claim 137
Independent Claim
202 words
A method of scrambling a composite television video signal having fields with each field having a vertical blanking interval followed by a sequence of lines of video information separated by a front porch, a horizontal synchronization pulse, a back porch and a colour burst portion associated with a given line of video information, said method comprising selectively delaying within a given field portions of the composite television signal by at least one time delay unit equal to or less than the sum of the durations of a front porch, a horizontal synchronization pulse and a back porch and each portion that is delayed including at least one colour burst portion and the associated line of video information to produce a scrambled signal wherein at least some of the horizontal synchronization pulses present in the composite television signal have been eliminated as a result of selectively delaying portions of the signal and the time duration between at least some other lines of adjacent video information has been increased, while maintaining at least substantially all of the lines of video information and associated colour burst portions and the vertical blanking interval, and including timing information to used during the unscrambling of the scrambled signal.
Claim 138
Dependent Claim
32 words
The method of scrambling a composite television video signal as claimed in claim 124 wherein the time delay unit is equal to or greater than the duration of a horizontal synchronization pulse.
Claim 139
Independent Claim
206 words
A method of scrambling a composite television video signal having vertical blanking intervals separated by intervals containing lines of video information which are in turn separated by horizontal synchronization pulses said method comprising producing from time to time at least one signal which corresponds to said composite television signal but delayed in time relative thereto and selecting from the composite signal and the at least one delayed signal to alter the time duration between adjacent lines of video information by increasing the spacing when a signal is selected which is delayed in time relative to the portion of the signal immediately preceding the delayed portion and reducing the time duration between adjacent lines of video information when the signal that is selected is advanced in time relative to the immediately preceding portion whereby the time duration between adjacent lines of video information in the composite signal is altered to produce a scrambled television signal wherein the time duration between at least some adjacent lines of video information has been increased or decreased and wherein the value of the reduction in the time duration between such at least some adjacent lines of video information is equal to at least the time duration of a horizontal synchronization pulse.
Claim 140
Independent Claim
206 words
A method of scrambling a composite television video signal having vertical blanking intervals separated by intervals containing lines of video information which are in turn separated by horizontal synchronization pulses said method comprising producing from time to time at least one signal which corresponds to said composite television signal but delayed in time relative thereto and selecting from the composite signal and the at least one delayed signal to alter the time duration between adjacent lines of video information by increasing the spacing when a signal is selected which is delayed in time relative to the portion of the signal immediately preceding the delayed portion and reducing the time duration between adjacent lines of video information when the signal that is selected is advanced in time relative to the immediately preceding portion whereby the time duration between adjacent lines of video information in the composite signal is altered to produce a scrambled television signal wherein the time duration between at least some adjacent lines of video information has been increased or decreased and wherein the value of the reduction in the time duration between such at least some adjacent lines of video information is equal to at least the time duration of a horizontal synchronization pulse.
Claim 141
Dependent Claim
47 words
The method of scrambling a composite television video signal as claimed in claim 126 wherein said step of selecting is controlled to eliminate at least the horizontal synchronization pulse between two lines of video information when decreasing the time duration between two adjacent lines of video information.
Claim 142
Dependent Claim
43 words
A method of scrambling a composite television video signal as claimed in claim 126 wherein the time duration between adjacent vertical blanking intervals remains unchanged and only the lines of video information and the horizontal synchronization pulses between vertical blanking intervals are scrambled.
Claim 143
Independent Claim
145 words
A method of scrambling a composite television video signal having blanking intervals separated by intervals containing lines of video information which are in turn separated by horizontal synchronization pulses said method comprising processing from time to time a portion of the composite television signal to provide a signal delayed in time relative thereto by an amount at least equal to the duration of a horizontal synchronization pulse to thereby increase the time duration between two adjacent lines of video information or between a vertical blanking interval and an adjacent line of video information, and returning to a signal from a portion delayed relative thereto in a controlled manner to decrease the time duration between the preceding line of video information and the first line of video information of the returned signal to eliminate a horizontal synchronization pulse between such delayed portion and such returned signal.
Claim 144
Independent Claim
145 words
A method of scrambling a composite television video signal having blanking intervals separated by intervals containing lines of video information which are in turn separated by horizontal synchronization pulses said method comprising processing from time to time a portion of the composite television signal to provide a signal delayed in time relative thereto by an amount at least equal to the duration of a horizontal synchronization pulse to thereby increase the time duration between two adjacent lines of video information or between a vertical blanking interval and an adjacent line of video information, and returning to a signal from a portion delayed relative thereto in a controlled manner to decrease the time duration between the preceding line of video information and the first line of video information of the returned signal to eliminate a horizontal synchronization pulse between such delayed portion and such returned signal.
Claim 145
Dependent Claim
74 words
Apparatus for scrambling a composite television video signal having intervals containing video information separated by horizontal synchronization pulses comprising means for shifting in time some portions of the composite television signal and control means for controlling said shifting means according to a predetermined scheme to produce a scrambled television signal in which at least some horizontal synchronization pulses between adjacent intervals containing video information are eliminated while maintaining substantially all of the video information.
Claim 146
Dependent Claim
74 words
Apparatus for scrambling a composite television video signal having intervals containing video information separated by horizontal synchronization pulses comprising means for shifting in time some portions of the composite television signal and control means for controlling said shifting means according to a predetermined scheme to produce a scrambled television signal in which at least some horizontal synchronization pulses between adjacent intervals containing video information are eliminated while maintaining substantially all of the video information.
Claim 147
Dependent Claim
17 words
Apparatus as claimed in claim 130 wherein said shifting means comprise digitally controlled analog shift register means.
Claim 148
Dependent Claim
33 words
Apparatus as claimed in claim 131 wherein said digitally controlled analogue shift register means comprises at least one charge coupled device having 91 elements and clocked at a frequency of approximately 14.31 MHz.
Claim 149
Dependent Claim
55 words
Apparatus as claimed in claim 130 wherein said shifting means comprises delay means to produce at least one signal corresponding to the composite television signal and having a time shift relative thereto and selecting means for selecting according to said predetermined scheme one of the composite television signal and said at least one corresponding signal.
Claim 150
Dependent Claim
26 words
Apparatus as claimed in claim 130 including feedback balancing means for compensating for any bias level offsets introduced by said digitally controlled analogue shift register means.
Claim 151
Dependent Claim
29 words
Apparatus as claimed in claim 130 including means for inserting digital data into the scrambled television signal representative of the predetermined scheme by which the television signal is scrambled.
Claim 152
Independent Claim
113 words
A method of scrambling a composite television signal having intervals containing video information separated by intervals containing synchronization information necessary for faithful reproduction by a television and of a predetermined or known repetitive form, said method comprising processing the signal to eliminate at least some of the synchronization information necessary for faithful reproduction by a television between adjacent video information and shifting such adjacent video information to decrease the time duration therebetween by a duration substantially equal to the duration of the eliminated necessary synchronization information, which, due to its predetermined or known repetitive form can be created and inserted during unscrambling as required to allow substantially faithful reproduction of the composite signal.
Claim 153
Independent Claim
113 words
A method of scrambling a composite television signal having intervals containing video information separated by intervals containing synchronization information necessary for faithful reproduction by a television and of a predetermined or known repetitive form, said method comprising processing the signal to eliminate at least some of the synchronization information necessary for faithful reproduction by a television between adjacent video information and shifting such adjacent video information to decrease the time duration therebetween by a duration substantially equal to the duration of the eliminated necessary synchronization information, which, due to its predetermined or known repetitive form can be created and inserted during unscrambling as required to allow substantially faithful reproduction of the composite signal.
Claim 154
Dependent Claim
33 words
A method as claimed in claim 136 wherein said step of shifting is controlled to maintain the order and integrity of substantially all of the video information and horizontal synchronization information is eliminated.
Claim 155
Dependent Claim
20 words
A method as claimed in claim 136 wherein the signal is processed to eliminate at least some horizontal synchronization pulses.
Claim 156
Dependent Claim
34 words
A method of scrambling a composite signal as claimed in claim 136 wherein the shifting of video information is controlled to retain a portion of the signal from which timing information can be derived.
Claim 157
Dependent Claim
118 words
Apparatus for scrambling a composite television video signal having intervals containing video information separated by intervals containing synchronization information necessary for faithful reproduction by a television and of a predetermined or known repetitive form, said apparatus comprising means for processing the signal to eliminate at least some of the synchronization information necessary for faithful reproduction by a television between adjacent video information and means for shifting such adjacent video information to decrease the time duration therebetween by a duration substantially equal to the duration of the eliminated necessary synchronization information, which, due to its predetermined or known repetitive form can be created and inserted during unscrambling as required to allow substantially faithful reproduction of the composite video signal.
Claim 158
Dependent Claim
118 words
Apparatus for scrambling a composite television video signal having intervals containing video information separated by intervals containing synchronization information necessary for faithful reproduction by a television and of a predetermined or known repetitive form, said apparatus comprising means for processing the signal to eliminate at least some of the synchronization information necessary for faithful reproduction by a television between adjacent video information and means for shifting such adjacent video information to decrease the time duration therebetween by a duration substantially equal to the duration of the eliminated necessary synchronization information, which, due to its predetermined or known repetitive form can be created and inserted during unscrambling as required to allow substantially faithful reproduction of the composite video signal.
Claim 159
Dependent Claim
19 words
Apparatus as claimed in claim 140 including means for controlling said shift means whereby horizontal synchronization information is eliminated.
Claim 160
Dependent Claim
56 words
Apparatus as claimed in claim 140 wherein said means for processing includes delay means to produce at least one signal corresponding to the composite television signal and having a time shift relative thereto and selecting means for selecting according to said predetermined scheme one of the composite television signal and said at least one corresponding signal.
Claim 161
Independent Claim
196 words
An apparatus for unscrambling a scrambled television signal scrambled by eliminating at least some necessary synchronization information of a predetermined or known repetitive form between adjacent intervals of video information and having at least some intervals of video information shifted according to a predetermined scheme and in a manner to decrease the time duration between at least some adjacent intervals of video information said apparatus comprising means for receiving a scrambled television signal, means for receiving timing information associated with such scrambled signal, means for shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal and means for creating and inserting in accordance with the timing information synchronization information eliminated during scrambling to produce an unscrambled signal substantially faithful relative to the original composite signal and wherein the scrambled signal includes a control signal indicative of said predetermined scheme and said unscrambler includes means for recognizing the control signal which determines the scheme determined by the predetermined scheme.
Claim 162
Independent Claim
196 words
An apparatus for unscrambling a scrambled television signal scrambled by eliminating at least some necessary synchronization information of a predetermined or known repetitive form between adjacent intervals of video information and having at least some intervals of video information shifted according to a predetermined scheme and in a manner to decrease the time duration between at least some adjacent intervals of video information said apparatus comprising means for receiving a scrambled television signal, means for receiving timing information associated with such scrambled signal, means for shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal and means for creating and inserting in accordance with the timing information synchronization information eliminated during scrambling to produce an unscrambled signal substantially faithful relative to the original composite signal and wherein the scrambled signal includes a control signal indicative of said predetermined scheme and said unscrambler includes means for recognizing the control signal which determines the scheme determined by the predetermined scheme.
Claim 163
Independent Claim
153 words
A method of unscrambling a scrambled television signal scrambed by eliminating at least some necessary synchronization information of a predetermined repetitive form between adjacent intervals of video information and having at least some intervals of video information shifted according to a predetermined scheme and in a manner to decrease the time duration between at least some adjacent intervals of video information said method comprising receiving a scrambled television signal, receiving timing information associated with such scrambled signal, shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal and creating and inserting in accordance with the timing information synchronization information eliminated during scrambling to produce an unscrambled signal substantially faithful relative to the original composite signal.
Claim 164
Independent Claim
153 words
A method of unscrambling a scrambled television signal scrambed by eliminating at least some necessary synchronization information of a predetermined repetitive form between adjacent intervals of video information and having at least some intervals of video information shifted according to a predetermined scheme and in a manner to decrease the time duration between at least some adjacent intervals of video information said method comprising receiving a scrambled television signal, receiving timing information associated with such scrambled signal, shifting in time according to a scheme determined by the predetermined scheme and in accordance with the timing information at least some adjacent lines of video information to re-establish the time duration between adjacent lines of video information to that as essentially found in the original television signal and creating and inserting in accordance with the timing information synchronization information eliminated during scrambling to produce an unscrambled signal substantially faithful relative to the original composite signal.
Claim 165
Dependent Claim
24 words
A method of unscrambling as claimed in claim 144 wherein horizontal synchronization pulses are eliminated during scrambling and are created and inserted during unscrambling.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-06-09 | 1989-12-09 | 1990-06-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-06-09 | 1993-12-09 | 1994-06-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-06-09 | 1997-12-09 | 1998-06-10 | $7700.00 | Window Closed / Lapsed |