US3739082A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Ordered dither system
Assignee: United States Department of the Army
•
Filing: 1972-02-29
•
Granted: 1973-06-12
•
Expires: 1992-02-29
Abstract
Abstract An improved system for transmission of either still or moving pictures, with or without scan interlace, and using only coarse quantization of the picture luminance, for conserving transmission channel capacity. This improvement is accomplished by combining the picture with a novel, two-dimensional ordered dither pattern. This pattern is arranged so that, without requiring expensive and complex synchronous subtraction of the dither signal at the receiver, and while operating with coarse quantization, a picture having relatively few disturbing noise structures, and of generally better quality, can be obtained than has been possible with dither systems heretofore. In addition, the dither pattern can be oriented so as to provide negligible large area flicker in those scanning systems which use line interlace. Finally, a reduction in aliasing effects, as well as further reduction in regular noise artifacts visible to the eye with ordered dither, can be achieved by causing the dither pattern to vary as a function of time.
Inventors
- 👤 B Lippel
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 21:49
CPC Classifications
H; H04; H04N; H04N19/00; H04N19/90
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
143 words
A system for transmission and reception of picture information comprising means for generating a two-dimensional ordered dither pattern coextensive in area with said picture, said pattern comprising an array of elements having a plurality of discrete amplitude levels, said elements being orthogonally arranged and comprising a dither subpattern of said elements which is repeated several times horizontally and vertically over the entire area of said picture, every horizontal group of four consecutive elements of said pattern having the same sum, every vertical group of four consecutive elements of said pattern having said same sum, and every group of four consecutive elements of said pattern disposed in a direction parallel to a diagonal of said subpattern having said same sum, means for adding said ordered dither pattern to said picture, and means for quantizing the sum of said picture and saiD ordered dither pattern.
Claim 2
Independent Claim
143 words
A system for transmission and reception of picture information comprising means for generating a two-dimensional ordered dither pattern coextensive in area with said picture, said pattern comprising an array of elements having a plurality of discrete amplitude levels, said elements being orthogonally arranged and comprising a dither subpattern of said elements which is repeated several times horizontally and vertically over the entire area of said picture, every horizontal group of four consecutive elements of said pattern having the same sum, every vertical group of four consecutive elements of said pattern having said same sum, and every group of four consecutive elements of said pattern disposed in a direction parallel to a diagonal of said subpattern having said same sum, means for adding said ordered dither pattern to said picture, and means for quantizing the sum of said picture and saiD ordered dither pattern.
Claim 3
Dependent Claim
71 words
A system for transmission and reception of picture information according to claim 1 wherein said picture is a frame of a moving picture comprising two fields related by two to one line interlace, and wherein said elements of said subpattern can be represented by up to four binary digits, and the three most significant binary digits appear the same number of times on odd and even horizontal rows of said matrix.
Claim 4
Dependent Claim
100 words
The system of claim 1 wherein said ordered dither subpattern corresponds to a nasik matrix of the species 0000 1011 1100 0111 1110 0101 0010 1001 0011 1000 1111 0100 1101 0110 0001 1010 including any number of successive reflections thereof about axes passing through any four linearly arranged elements, where the geometrical distribution of amplitudes of the elements of said dither subpattern corresponds to the geometrical distribution of values of the numbers in said matrix, wherein said numbers are expressed herein in binary form and all of which numbers may be altered by algebraic addition of the same constant.
Claim 5
Dependent Claim
35 words
The system of claim 3 wherein said ordered dither subpattern is any nasik matrix derived from the species therein by deleting from all numbers consistently any of the four bits of a given binary significance.
Claim 6
Dependent Claim
100 words
The system of claim 1 wherein said ordered dither subpattern corresponds to a nasik matrix of the species 0000 1101 1010 0111 1110 0011 0100 1001 0101 1000 1111 0010 1011 0110 0001 1100 including any number of successive reflections thereof about axes passing through any four linearly arranged elements, where the geometrical distribution of amplitudes of the elements of said dither subpattern corresponds to the geometrical distribution of values of the numbers in said matrix, wherein said numbers are expressed herein in binary form and all of which numbers may be altered by algebraic addition of the same constant.
Claim 7
Dependent Claim
35 words
The system of claim 5 wherein said ordered dither subpattern is any nasik matrix derived from the species therein by deleting from all numbers consistently any of the four bits of a given binary significance.
Claim 8
Dependent Claim
27 words
The system of claim 1 wherein said picture is a moving picture and further including means for varying said ordered dither pattern as a function of time.
Claim 9
Dependent Claim
55 words
The system of claim 7 wherein two dither patterns are alternated said dither pattern being defined by two dither matrices so related that the most significant digits of all of the binary numbers of one of the matrices are the complements of the most significant digits of all corresponding binary numbers of the other matrix.
Claim 10
Dependent Claim
235 words
Apparatus for transmission and reception of information representative of a picture comprising: means for sampling and orthogonally scanning said picture to provide a train of video pulses which have amplitude levels representing the brightness values of corresponding scanned elemental portions of the picture; means for generating an ordered repetitive sequence of p sets of 2n dither pulses, where n is any integer from 1 to 4, for each complete scan of said picture which is synchronized with the video pulses derived during scanning of said elemental portions of the picture; said scanning means comprising a horizontal deflection counter establishing a binary number CD and a vertical deflection counter establishing a binary number AB, the numbers CD and AB being respectively the horizontal and vertical counts modulo-4; said means for generating comprising a code translator for deriving from the binary digits A, B, C and D at least one of four binary digits W, X, Y and Z according to the following logical equations: W B C D X B C Y A B D Z A D the derived binary digits, taken in any order, representing a binary number; digital-to-analog converter means for converting successive and binary numbers to a repetitive series of analog dither pulses; means for adding said synchronized dither pulses and video pulses; and quantizing means having a quantizer step S for quantizing the sum of said dither pulses and video pulses.
Claim 11
Dependent Claim
235 words
Apparatus for transmission and reception of information representative of a picture comprising: means for sampling and orthogonally scanning said picture to provide a train of video pulses which have amplitude levels representing the brightness values of corresponding scanned elemental portions of the picture; means for generating an ordered repetitive sequence of p sets of 2n dither pulses, where n is any integer from 1 to 4, for each complete scan of said picture which is synchronized with the video pulses derived during scanning of said elemental portions of the picture; said scanning means comprising a horizontal deflection counter establishing a binary number CD and a vertical deflection counter establishing a binary number AB, the numbers CD and AB being respectively the horizontal and vertical counts modulo-4; said means for generating comprising a code translator for deriving from the binary digits A, B, C and D at least one of four binary digits W, X, Y and Z according to the following logical equations: W B C D X B C Y A B D Z A D the derived binary digits, taken in any order, representing a binary number; digital-to-analog converter means for converting successive and binary numbers to a repetitive series of analog dither pulses; means for adding said synchronized dither pulses and video pulses; and quantizing means having a quantizer step S for quantizing the sum of said dither pulses and video pulses.
Claim 12
Dependent Claim
24 words
Apparatus according to claim 9 wherein at least one of the binary digits W, X, Y and Z is replaced by its binary complement.
Claim 13
Dependent Claim
33 words
Apparatus according to claim 9 wherein said picture is a moving picture and one of said binary digits, W, X, Y and Z alternates with its binary complement as a function of time.
Claim 14
Dependent Claim
59 words
Apparatus according to claim 9 wherein said picture is a frame of a motion picture comprising two fields related by two to one line interlace wherein the digits of said binary number are taken in such order that all but the digit of the fourth ranking significance, if any, occur with equal frequency during each of said interlaced fields.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-06-11 | 1976-12-11 | 1977-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-06-11 | 1980-12-11 | 1981-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-06-11 | 1984-12-11 | 1985-06-12 | $7700.00 | Window Closed / Lapsed |