Patent US2870671A successfully refreshed from Google Patents.
Patent US3603725A successfully refreshed from Google Patents.
US3603725A
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Conditional replenishment video system with reduced buffer memory delay
Assignee: AT&T Inc
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Filing: 1970-01-15
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Granted: 1971-09-07
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Expires: 1990-01-15
Abstract
Abstract Amplitude samples from a video signal for an entire frame are stored in a frame memory. Each new sampled amplitude of the video signal is compared with a previously stored amplitude corresponding to the same spatial point in the video frame. If the difference between the two amplitudes exceeds a threshold value, the new amplitude replaces the old sample in the frame memory and is written into a buffer memory apparatus for storage prior to transmission to a receiving location. An address word is generated for each sample in order to indicate by its value the location of its corresponding sample within the video frame. The address word for each selected sample is also written into the buffer memory which is read on a first-in-first-out basis. The address of each new sample is compared with the address of a sample being held by the buffer memory apparatus in readiness for transmission to the receiving location. If the two addresses being compared correspond to the same spatial point in the video frame, the new sample is written into the buffer memory and the old sample is read out of the buffer memory even though the latter sample may not be coupled by the buffer memory apparatus to a transmitter for transmission to the receiving location. As a result, less delay is introduced by the buffer memory apparatus since the most recent amplitudes for the spatial points are coupled to the transmitter.
Inventors
- 👤 Cassius Chapin Cutler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 15:00
CPC Classifications
H; H04; H04N; H04N19/00; H04N19/10; H04N19/134; H04N19/146; H04N19/152; H04N19/50; H04N19/503
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
184 words
In a redundancy reduction system wherein amplitude samples are selected from an input signal having frame intervals, each one of said amplitude samples having an address location in said frame interval, buffering apparatus for matching the relativity random rate of selected samples to the rate of a transmission system comprising a buffer memory means for storing the amplitude of each one of said selected samples along with its corresponding address, means responsive to said transmission system for reading out said buffer memory means at a rate which can be utilized by said transmission system, means for comparing the address of a new sample with the address of a stored sample in readiness to be read out to said transmission system, and means for writing the amplitude and address of said new sample into said buffer memory means and for reading out the amplitude and address of said sample in readiness in response to an output from said means for comparing when the address of said new sample and the address of said sample in readiness correspond to the same location in said frame interval.
Claim 2
Dependent Claim
184 words
In a redundancy reduction system wherein amplitude samples are selected from an input signal having frame intervals, each one of said amplitude samples having an address location in said frame interval, buffering apparatus for matching the relativity random rate of selected samples to the rate of a transmission system comprising a buffer memory means for storing the amplitude of each one of said selected samples along with its corresponding address, means responsive to said transmission system for reading out said buffer memory means at a rate which can be utilized by said transmission system, means for comparing the address of a new sample with the address of a stored sample in readiness to be read out to said transmission system, and means for writing the amplitude and address of said new sample into said buffer memory means and for reading out the amplitude and address of said sample in readiness in response to an output from said means for comparing when the address of said new sample and the address of said sample in readiness correspond to the same location in said frame interval.
Claim 3
Dependent Claim
107 words
Apparatus as defined in claim 1 wherein the address specifies the location of its corresponding sample within a subinterval of said frame interval and said means for comparing the address of a new sample with the address of a stored sample includes a first subinterval detector means responsive to a particular address of said new sample for providing a digital word whose value indicates the particular subinterval to which said new sample belongs, and further includes a second subinterval detector means responsive to a particular address of said stored sample for providing a digital word whose value indicates the particular subinterval to which said stored sample belongs.
Claim 4
Dependent Claim
58 words
Apparatus as defined in claim 2 wherein said first and second subinterval detector means each includes a detector circuit for providing an energizing signal in response to the detection of said particular address, and a counter circuit for providing a digital word whose value is a function of the number of energizing signals provided by said detector circuit.
Claim 5
Dependent Claim
57 words
Apparatus as defined in claim 3 wherein said first subinterval detector means further includes a means responsive to the energizing signal provided by said detector circuit of said first subinterval detector means for writing the address and amplitude of said new sample into said buffer memory means even though said new sample is not a selected sample.
Claim 6
Dependent Claim
84 words
Apparatus ad defined in claim 3 wherein said means for reading out said buffer memory means includes an auxiliary buffer memory means, means for reading out said auxiliary buffer means in response to an energizing pulse from said transmission system, and means for writing into said auxiliary buffer means both in response to said energizing pulse from said transmission system and in response to the simultaneous occurrence of an output from said means for comparing and energizing signal from said second subinterval detector means.
Claim 7
Dependent Claim
91 words
Apparatus as defined in claim 5 wherein said means for reading out said buffer memory means further includes means for counting the number of samples stored in said auxiliary buffer memory means and for providing an output signal when the number of samples stored in said auxiliary buffer memory means exceeds a predetermined number, and said means for writing into said auxiliary buffer memory means includes means responsive to said output signal for prohibiting writing into said auxiliary buffer memory means in response to said energizing pulse from said transmission system.
Claim 8
Dependent Claim
236 words
A conditional replenishment video system in which a video signal having frame intervals is sampled to provide amplitude digital words each one of which indicates by its value the amplitude of a video signal sample, means for generating address digital words each one of which indicates by its value the position of a corresponding one of said amplitude words in said frame interval, means for selecting the amplitude digital words which represent significant changes in amplitude from their corresponding amplitudes in a previous video frame, digital transmission apparatus, and buffer memory apparatus for coupling the selected amplitude digital words and their corresponding address words to said digital transmission apparatus; said buffer memory apparatus comprising a buffer memory means for storing selected amplitude digital words and their corresponding address words, means for reading out a stored amplitude and address digital word from said buffer memory means on a first-in first-out basis, means for coupling the readout amplitude and address digital word to said digital transmission apparatus, means for comparing the address word of a newly generated amplitude word with the address word of said stored amplitude word, and means for writing said newly generated amplitude and address digital word into said buffer memory means in response to said means for comparing when the address of said newly generated amplitude word and the address of said stored amplitude word correspond to the same position in said frame interval.
Claim 9
Dependent Claim
236 words
A conditional replenishment video system in which a video signal having frame intervals is sampled to provide amplitude digital words each one of which indicates by its value the amplitude of a video signal sample, means for generating address digital words each one of which indicates by its value the position of a corresponding one of said amplitude words in said frame interval, means for selecting the amplitude digital words which represent significant changes in amplitude from their corresponding amplitudes in a previous video frame, digital transmission apparatus, and buffer memory apparatus for coupling the selected amplitude digital words and their corresponding address words to said digital transmission apparatus; said buffer memory apparatus comprising a buffer memory means for storing selected amplitude digital words and their corresponding address words, means for reading out a stored amplitude and address digital word from said buffer memory means on a first-in first-out basis, means for coupling the readout amplitude and address digital word to said digital transmission apparatus, means for comparing the address word of a newly generated amplitude word with the address word of said stored amplitude word, and means for writing said newly generated amplitude and address digital word into said buffer memory means in response to said means for comparing when the address of said newly generated amplitude word and the address of said stored amplitude word correspond to the same position in said frame interval.
Claim 10
Dependent Claim
115 words
Apparatus as defined in claim 7 wherein each address digital word specifies the position of its corresponding sample within a subinterval of said frame interval and said means for comparing the address word of a newly generated sample with the address word of said stored sample includes a first subinterval detector means responsive to a particular address word of said newly generated sample for providing a digital word whose value indicates the particular subinterval to which said new sample belongs, and further includes a second subinterval detector means responsive to a particular address word of said stored sample for providing a digital word whose value indicates the particular subinterval to which said stored sample belongs.
Claim 11
Dependent Claim
60 words
Apparatus as defined in claim 8 wherein said first and second subinterval detector means each includes a detector circuit for providing an energizing signal in response to the detection of said particular address word, and a counter circuit for providing an output digital word whose value is a function of the number of energizing signals provided by said detector cIrcuit.
Claim 12
Dependent Claim
58 words
Apparatus as defined in claim wherein said first subinterval detector means further includes a means responsive to the energizing signal provided by said detector circuit of said first subinterval detector means for writing the address and amplitude of said newly generated sample into said buffer memory means even though said newly generated sample is not a selected sample.
Claim 13
Dependent Claim
92 words
Apparatus as defined in claim 9 wherein said means for coupling the readout amplitude and address digital word to said digital transmission apparatus includes an auxiliary buffer memory means, means for reading out said auxiliary buffer means in response to an energizing pulse from said transmission system, and means for writing into said auxiliary buffer means both in response to said energizing pulse from said transmission apparatus and in response to the simultaneous occurrence of an output from said means for comparing and an energizing signal from said second subinterval detector means.
Claim 14
Dependent Claim
98 words
Apparatus as defined in claim 11 wherein said means for coupling the readout amplitude and address digital word to said digital transmission apparatus further includes means for counting the number of samples stored in said auxiliary buffer memory means and for providing an output signal when the number of samples stored in said auxiliary buffer memory means exceeds a predetermined number, and said means for writing into said auxiliary buffer memory means includes means responsive to said output signal for prohibiting writing into said auxiliary buffer memory means in response to said energizing pulse from said transmission apparatus.
References Cited (Backward Citations)
US2909601A
Cited
US3016422A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-09-06 | 1975-03-08 | 1975-09-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-09-06 | 1979-03-08 | 1979-09-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-09-06 | 1983-03-08 | 1983-09-07 | $7700.00 | Window Closed / Lapsed |