US3871019A
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Line sequential color television recording system
Assignee: RCA Corp
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Filing: 1973-04-13
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Granted: 1975-03-11
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Expires: 1993-04-13
Abstract
Abstract A line sequential color signal coding format for a limited bandwidth video recording system is disclosed which achieves improved vertical transient response during playback display. Spectrum interleaving is employed between the luminance signal and color difference chrominance signals during encoding, with the necessary signal separation during decoding being effected by comb filtering using delay lines. Prefiltering may be implemented during encoding to comb out crosstalk producing signals from the luminance and chrominance signal spectrums. To avoid contamination of the mixed high frequency luminance components in the decoder by the switched low frequency components, the composite signal may be fed through a high pass luminance filter in the decoder whose cutoff frequency is above that of a low pass filter in the encoder through which the switched, line sequential components are fed.
Inventors
- 👤 Joseph Peter Bingham
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 07:45
CPC Classifications
H; H04; H04N; H04N9/00; H04N9/79; H04N9/80; H04N9/86; H04N9/81
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
180 words
A line sequential encoder for a color television recording system, comprising: a. input means supplying a set of color signals representative of a color image scanned in a series of lines; b. an encoding matrix coupled to the input means for deriving therefrom a luminance signal comprising components whose frequencies lie primarily at integral multiples of the horizontal line scanning frequency and a plurality of color difference signals comprising components whose frequencies lie primarily at integral multiples of the horizontal line scanning frequency; c. switching means synchronized with the horizontal line scanning frequency for sequentially coupling each one of the plurality of color difference signals to an output terminal in a cyclic, repetitive manner to develop a chrominance signal at said output terminal comprising components whose frequencies lie primarily at spectral locations intervening integral multiples of the line scanning frequency; and d. adding means, responsive to the luminance signal derived by said matrix and to the chrominance signal developed at said switching means output terminal, for combining said luminance and chrominance signals to provide a composite output signal for recordation.
Claim 2
Dependent Claim
180 words
A line sequential encoder for a color television recording system, comprising: a. input means supplying a set of color signals representative of a color image scanned in a series of lines; b. an encoding matrix coupled to the input means for deriving therefrom a luminance signal comprising components whose frequencies lie primarily at integral multiples of the horizontal line scanning frequency and a plurality of color difference signals comprising components whose frequencies lie primarily at integral multiples of the horizontal line scanning frequency; c. switching means synchronized with the horizontal line scanning frequency for sequentially coupling each one of the plurality of color difference signals to an output terminal in a cyclic, repetitive manner to develop a chrominance signal at said output terminal comprising components whose frequencies lie primarily at spectral locations intervening integral multiples of the line scanning frequency; and d. adding means, responsive to the luminance signal derived by said matrix and to the chrominance signal developed at said switching means output terminal, for combining said luminance and chrominance signals to provide a composite output signal for recordation.
Claim 3
Dependent Claim
180 words
A line sequential encoder for a color television recording system, comprising: a. input means supplying a set of color signals representative of a color image scanned in a series of lines; b. an encoding matrix coupled to the input means for deriving therefrom a luminance signal comprising components whose frequencies lie primarily at integral multiples of the horizontal line scanning frequency and a plurality of color difference signals comprising components whose frequencies lie primarily at integral multiples of the horizontal line scanning frequency; c. switching means synchronized with the horizontal line scanning frequency for sequentially coupling each one of the plurality of color difference signals to an output terminal in a cyclic, repetitive manner to develop a chrominance signal at said output terminal comprising components whose frequencies lie primarily at spectral locations intervening integral multiples of the line scanning frequency; and d. adding means, responsive to the luminance signal derived by said matrix and to the chrominance signal developed at said switching means output terminal, for combining said luminance and chrominance signals to provide a composite output signal for recordation.
Claim 4
Dependent Claim
180 words
A line sequential encoder for a color television recording system, comprising: a. input means supplying a set of color signals representative of a color image scanned in a series of lines; b. an encoding matrix coupled to the input means for deriving therefrom a luminance signal comprising components whose frequencies lie primarily at integral multiples of the horizontal line scanning frequency and a plurality of color difference signals comprising components whose frequencies lie primarily at integral multiples of the horizontal line scanning frequency; c. switching means synchronized with the horizontal line scanning frequency for sequentially coupling each one of the plurality of color difference signals to an output terminal in a cyclic, repetitive manner to develop a chrominance signal at said output terminal comprising components whose frequencies lie primarily at spectral locations intervening integral multiples of the line scanning frequency; and d. adding means, responsive to the luminance signal derived by said matrix and to the chrominance signal developed at said switching means output terminal, for combining said luminance and chrominance signals to provide a composite output signal for recordation.
Claim 5
Dependent Claim
14 words
a first two input adder including means for inverting one of said two inputs,
Claim 6
Dependent Claim
14 words
a first two input adder including means for inverting one of said two inputs,
Claim 7
Dependent Claim
38 words
a plurality of series connected delay elements each providing a time delay equal to one horizontal line scanning period and defining input, intermediate, and output signal nodes, the input signal node being coupled to the supply means, and
Claim 8
Dependent Claim
38 words
a plurality of series connected delay elements each providing a time delay equal to one horizontal line scanning period and defining input, intermediate, and output signal nodes, the input signal node being coupled to the supply means, and
Claim 9
Dependent Claim
57 words
decoding matrix means receiving inputs from predetermined ones of the signal nodes for simultaneously deriving therefrom each one of the plurality of color difference signals, and d. commutator means receiving the chrominance signals from the decoding matrix means for simultaneously and individually coupling each color difference signal to a predetermined one of a plurality of commutator outputs.
Claim 10
Dependent Claim
57 words
decoding matrix means receiving inputs from predetermined ones of the signal nodes for simultaneously deriving therefrom each one of the plurality of color difference signals, and d. commutator means receiving the chrominance signals from the decoding matrix means for simultaneously and individually coupling each color difference signal to a predetermined one of a plurality of commutator outputs.
Claim 11
Dependent Claim
16 words
means for coupling the input and second intermediate signal nodes to the two first adder inputs,
Claim 12
Dependent Claim
16 words
means for coupling the input and second intermediate signal nodes to the two first adder inputs,
Claim 13
Dependent Claim
34 words
A line sequential encoder as defined in claim 1 further comprising a low pass filter connected between the switching means and the adding means for limiting the upper frequency of the color difference signals.
Claim 14
Dependent Claim
44 words
A line sequential encoder as defined in claim 1 wherein the luminance signal (Y) encompasses frequencies beyond the highest frequency of said color difference signals, and said plurality of color difference signals comprise three signals respectively equal to (G-Y), 0.51 (R-Y) and 0.19 (B-Y).
Claim 15
Dependent Claim
15 words
a second two input adder including means for inverting one of said two inputs, and
Claim 16
Dependent Claim
15 words
a second two input adder including means for inverting one of said two inputs, and
Claim 17
Dependent Claim
16 words
means for coupling the first intermediate and output signal nodes to the two second adder inputs.
Claim 18
Dependent Claim
16 words
means for coupling the first intermediate and output signal nodes to the two second adder inputs.
Claim 19
Dependent Claim
55 words
A line sequential encoder as defined in claim 2 wherein the luminance signal (Y) encompasses frequencies beyond the highest frequency of said color difference signals, and said plurality of color difference signals comprise three signals respectively equal to 0.493 (B-Y), 0.877 (R-Y) cos 30*-0.493 (B-Y) cos 60*, and -0.877 (R-Y) cos 30*-.493 (B-Y) cos 60*.
Claim 20
Dependent Claim
77 words
A line sequential encoder as defined in claim 1 further including means for prefiltering the luminance signal prior to combination with said chrominance signal in said adding means to remove therefrom luminance signal components whose frequencies lie at said intervening spectral locations, and means for prefiltering said chrominance signal prior to combination with said luminance signal in said adding means to remove therefrom chrominance signal components whose frequencies lie at integral multiples of the line scanning frequency.
Claim 21
Dependent Claim
20 words
A line sequential encoder as defined in claim 5 wherein each of said prefiltering means comprises a separate comb filter.
Claim 22
Dependent Claim
66 words
A line sequential encoder as defined in claim 6 wherein said luminance signal prefiltering means further includes means for separating the low frequency and high frequency components of the luminance signal means for applying the low frequency components of the luminance signal to the luminance comb fIlter, and means for recombining the combed low frequency components of the luminance signal with the high frequency components thereof.
Claim 23
Dependent Claim
34 words
A line sequential encoder as defined in claim 7 further comprising a low pass filter connected between the switching means and the chrominance comb filter for limiting the upper frequency of the chrominance signals.
Claim 24
Dependent Claim
60 words
A line sequential encoder as defined in claim 8 wherein there are three chrominance signals and both the luminance and chrominance comb filters each comprise two series connected delay elements each providing a time delay equal to one horizontal line scanning period, and matrix means supplied with the signals at the input, intermediate and output nodes of the delay elements.
Claim 25
Dependent Claim
63 words
A line sequential decoder for a color television recording system wherein the signal coding format for each horizontal line of the scanned image comprises a luminance signal and one of a plurality of sequential repeating color difference signals, comprising: a. means supplying a composite recorded input signal, b. means for deriving a luminance signal from the input signal, c. comb filtering means comprising:
Claim 26
Dependent Claim
63 words
A line sequential decoder for a color television recording system wherein the signal coding format for each horizontal line of the scanned image comprises a luminance signal and one of a plurality of sequential repeating color difference signals, comprising: a. means supplying a composite recorded input signal, b. means for deriving a luminance signal from the input signal, c. comb filtering means comprising:
Claim 27
Dependent Claim
44 words
A line sequential decoder as defined in claim 10 wherein the means for deriving a luminance signal comprises a further comb filter comprising said plurality of series connected delay elements and further decoding matrix means receiving inputs from predetermined ones of the signal nodes.
Claim 28
Dependent Claim
57 words
A line sequential decoder as defined in claim 11 wherein: a. the sequence of the color difference signals repeats every four horizontal lines and is of the form +a, +b, -a, -b, g. there are three series connected delay elements defining input, first intermediate, second intermediate, and output signal nodes, and c. the decoding matrix means comprises:
Claim 29
Dependent Claim
29 words
A line sequential decoder as defined in claim 12 wherein the further decoding matrix means comprises means for adding the signals at the input and second intermediate signal nodes.
Claim 30
Dependent Claim
87 words
A line sequential decoder as defined in claim 11 wherein: a. the sequence of the color difference signals repeats every three horizontal lines and is of the form +a, -(a+b), +b, b. there are two series connected delay elements, and c. the decoding matrix means receives three input signals from the input, intermediate and output signal nodes, and derives therefrom three color difference output signals, each output signal being equal to one of the input signals minus onehalf of the sum of the other two input signals.
Claim 31
Dependent Claim
29 words
A line sequential decoder as defined in claim 14 wherein the further decoding matrix means comprises means for adding the signals at the input, intermediate, and output signal nodes.
Claim 32
Dependent Claim
74 words
A line sequential decoder as defined in claim 15 further comprising: a. first filter means connected between the supplying meAns and the input signal node for limiting the upper frequency of the composite input signal, b. second filter means connected to the supplying means for limiting the lower frequency of the composite input signal, and c. means for adding the output from the second filter means and the adding means recited in claim 15.
Claim 33
Dependent Claim
36 words
A line sequential decoder as defined in claim 10 wherein the means for deriving a luminance signal comprises means for adding the composite input signal and an inverted one of the plurality of color difference signals.
Claim 34
Dependent Claim
86 words
A line sequential decoder as defined in claim 17 wherein: a. the sequence of the chrominance signals repeats every three horizontal lines and is of the form +a, -(a+b), +b, b. there are two series connected delay elements, and c. the decoding matrix means receives three input signals from the input, intermediate, and output signal nodes, and derives therefrom three color difference output signals, each output signal being equal to one of the input signals minus one-half of the sum of the other two input signals.
Claim 35
Dependent Claim
83 words
A line sequential decoder as defined in claim 18 wherein the decoding matrix means comprises: a. three differential amplifiers each having a noninverting input and an inverting input, b. means individually connecting the signal at the input, intermediate, and output signal nodes to respective ones of the noninverting amplifier inputs, and c. means individually connecting one-half of the sum of the signals at the two nodes not connected to the noninverting input of each amplifier to the inverting input of each said amplifier.
Claim 36
Dependent Claim
46 words
A line sequential decoder as defined in claim 19 wherein the inverted one of the plurality of chrominance signals recited in claim 17 is derived from an inverter connected to the output of the differential amplifier whose noninverting input is connected to the input signal node.
Claim 37
Dependent Claim
20 words
A line sequential decoder as defined in claim 20 further comprising means for adjusting the amplitude of the inverter output.
Claim 38
Dependent Claim
23 words
A line sequential decoder as defined in claim 19 wherein the means recited in sub-paragraph (c) of claim 19 comprises resistive summing networks.
Claim 39
Dependent Claim
33 words
A line sequential decoder as defined in claim 10 further comprising filter means connected between the supplying means and the input signal node for limiting the upper frequency of the composite recorded signal.
Claim 40
Dependent Claim
32 words
A line sequential decoder as defined in claim 10 further comprising means connected between the supplying means and the commutator means for recovering a color synchronizing signal from the composite recorded signal.
Claim 41
Dependent Claim
38 words
A line sequential decoder as defined in claim 20 further comprising delay means connected between the supplying means and the adding means for compensating for any phase imbalance between the composite input signal and the inverted chrominance signal.
Claim 42
Dependent Claim
59 words
A line sequential decoder as defined in claim 10 wherein the chrominance signal interleaved in the composite recorded signal have an upper frequency limit, and further comprising filter means connected to the supplying means for limiting the lower frequency of the signal coupled to the means for deriving a luminance signal to a value above said upper frequency limit.
References Cited (Backward Citations)
US3598904A
Cited
US3730983A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |