CN1062079C - FM and AM netting method - Google Patents
FM and AM netting method Download PDFInfo
- Publication number
- CN1062079C CN1062079C CN95106737A CN95106737A CN1062079C CN 1062079 C CN1062079 C CN 1062079C CN 95106737 A CN95106737 A CN 95106737A CN 95106737 A CN95106737 A CN 95106737A CN 1062079 C CN1062079 C CN 1062079C
- Authority
- CN
- China
- Prior art keywords
- subnet
- random
- area
- grid cell
- subnet point
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Image Processing (AREA)
- Facsimile Image Signal Circuits (AREA)
Abstract
The present invention relates to a netting technique in chromatic printing, particularly to an FM and AM netting method which integrates the advantages of traditional AM netting and FM netting. The number of son net points in unit lattices is random and is generally within the range of 1 to 10. The area of each son net point is random within the range of an upper bound and a lower bound; the upper bound is determined by printing quality and the lower bound is determined by printing technology. The positions of the son net points in lattice units are random within a certain range but are not superposed. Ordered superposition is eliminated and simultaneously, uncontrollable factors in the netting are reduced through the random determination of the sizes, the number and the positions of the son net points. The present invention has the advantages of no Moire pattern and no rose macula, and can be used for practical printing.
Description
The present invention relates to a kind of manufacture method of galley, relate to the net hanging method in a kind of colored printing or rather.
Linked network in the colored printing is exactly the technical finesse process with image latticeization, be about to the colored original color separation for blue or green (C), product (M), yellow (Y), deceive (K) four table images of throwing the net, the ratio that accounts for the grid cell area with the ink dot area in each grid cell is controlled gray scale.Grid image after the linked network can be outputed on the four coloring agent sheets by laser photocomposing machine, and four film of throwing the net record green grass or young crops, product, Huang, black gray-scale value respectively, and then by film makeup, finally print with forme.Therefore screening technology is one of technology of most critical in the colored printing always, and the quality of net hanging method directly influences the quality of chromatograp and the slice speed of four look films.
The screening technology exist of existing colored printing is having two class methods: amplitude modulation screening and frequency-modulation screening are to be made by the reasonable linked network or the compound screening technology of amplitude modulation screening as present chromatograp great majority.
Has only a site in the amplitude modulation screening in the grid cell of screen by laser explosure, and be distributed in the center of grid, the formation gray level that varies in size of site, the site can be garden shape, square, ellipse garden shape etc. as required, moir and rose spot can appear in the amplitude modulation net when four-colour chromatography, outstanding amplitude modulation screening technology can only be avoided big moire (moir), because the structure of screen is well-regulated periodic arrangement, screen of all kinds the rose spot will inevitably occur because of its order stack, thereby the rose spot is inevitable.
The fixed-size particulate point of stochastic distribution (laser spots of 4-35 μ m) in the grid cell of screen in the frequency-modulation screening is by the gray scale of how much controlling of particulate point.Because modulating net makes particulate point stochastic distribution in grid cell, has upset the periodicity of former amplitude modulation net, can not produce moir and rose spot during chromatography, solved a difficult problem maximum in the amplitude modulation net.But modulating net will be put with minimum particulate and replace conventional amplitude modulation site, to printing process some specific (special) requirements must be proposed, as forme resolution, space of a whole page cleanliness, ink-water balance etc., because the restriction of technological level almost can't realize, particularly the enlarged areas rate of frequency-modulation halftone dot is proportional to particulate and counts out, thereby modulating net has very big dot gain rate than amplitude modulation net, in addition, when particulate point is very little, the shape of transfer process mid point becomes irregular, and yet corresponding the becoming of its length of side and enlarged areas rate there is not rule.This shows that modulating net has but brought insoluble problem and uncertain factor in many typographies when solving amplitude modulation net drawback, therefore by present typography level, modulating net has only theoretical value, and does not have the possibility of practical application.
The objective of the invention is on the basis of analyzing amplitude modulation net and modulating net basic structure comprehensive its advantage, overcome its shortcoming and design a kind of FM and AM netting method, can solve the rose spot substantially, practical and guarantee printing quality on technology.
A kind of FM and AM netting method, with the coloured image master copy color-dividing is green grass or young crops, product, Huang, black four table images of throwing the net, the ratio that accounts for the grid cell area with subnet point area in each grid cell of each grid image is controlled gray shade scale and is counted G, it is characterized in that comprising:
1) gives net number purpose value range Z, screening screen density L, subnet point area lower limit S at random in the user input unit grid
M, subnet point area upper limit S
NAnd dot shape;
2) count G by screening screen density L and gray shade scale and calculate the S of minimum area unit that constitutes subnet point
i, S
i=1/ (L
2* G), G can be decided to be 256, and by subnet point area lower limit S
MCalculate subnet point area lower limit N at random
M=S
M/ S
i, N
MRound numbers;
3) by grid cell densitometer operator site total area M, M=A% * (1/L
2), A% is a theoretic surface coverage in the grid cell;
4) in the Z of the scope at random value that subnet is counted out, produce a random number as the subnet of this grid cell K that counts by randomizer;
5) by subnet point area upper limit S
NDetermine subnet point area upper limit N at random
A, N
A=S
N/ S
i, N
ARound numbers;
6) subnet being put total area M random division is K sub-dot area, makes each subnet point area at N
MAnd N
AIn the scope;
7) be the border with the grid cell but producing each subnet point position in grid cell by randomizer in the limited range of nonoverlapping position.
Described subnet is counted out at random, and value range Z is 1-10; The lower limit of described subnet point area is by the decision of typography level, and the upper limit of described subnet point area is to be determined by printing quality.
Described dot shape is circular, square, rhombus, ellipse.
It is described that subnet is put total area M random division is that K sub-dot area is the division methods that adopts homalographic.
FM and AM netting method of the present invention, be in the screen unit grid site by number be 1 to 10, size in the upper limit, lower range at random, position at random subnet point in grid forms.
Said method neutron site determined by three kinds of random factors, and promptly to count out be within the specific limits at random to subnet, generally gets 1-10, and under the prerequisite of ensuring the quality of products subnet count out should be less; The size of subnet point also within the specific limits at random, the upper limit of this scope determines that by desired printing quality lower limit is then determined by the typography level; The position of subnet point in grid cell at random.This method makes under the constant constraint of total gray scale in the grid cell that subnet is counted out, subnet point size, subnet point position are all definite at random, be exactly in order thoroughly to eliminate the order of grid, to eliminate because of the regular moir that produces, rose spot etc. with random technology.
Problem said method notes following six in implementation process aspect:
1, when coloured image was divided into grid by required screen density, gray level was 256 generally speaking, and after C, M, Y, K four color shades were pressed 256 grades of quantifications, the number percent A% that gray scale and dot area account for the grid cell area should satisfy simple linear relationship; Number percent A%=gray scale/256;
2, subnet point area lower limit is determined by the typography level, because the group dot area is during less than certain value, the amplification degree of site and shape will be difficult to control, therefore should be when distributing subnet point area less than this certain value, the subnet point area upper limit is decided by desired printing quality, the size of subnet point should not surpass the human eye vision resolution limit, be equivalent to 175Lpi under the normal sighting distance (extension screen density), when hanging screen density L greater than 175Lpi, the area upper limit of subnet point is the unit grid area, when hanging screen density L less than 175Lpi, the area upper limit of subnet point should be less than S (unit grid area)/(175/L)
2, subnet point area should be limited in the upper and lower limit scope at random;
3, the shape of subnet point can need be decided to be circle, square, rhombus, ellipse etc. by the user, and wherein circle is a shape commonly used;
4, when random division subnet point area, also can adopt the homalographic division methods in order to accelerate linked network speed;
5, when determining the position of subnet point in grid cell at random, border that can grid cell is as limited range, though guarantee not with grid cell on every side in can exceed this border under the overlapping condition of subnet point, but the correlation computations of introducing can obviously reduce linked network speed thus, each subnet point can not be overlapped in same grid cell, if have overlapping should be again picked at random again, till all-ones subnet point all satisfies condition in grid.During enforcement in order to improve linked network speed, can be with position limit stochastic distribution in certain zone of grid cell of each subnet point, with the probability that reduces overlapping and super border, the number of times that random function is called in minimizing, but limit the order that must increase grid artificially, order can cause interference to a certain degree, therefore effect must should determine according to quality, speed balance not as good at random;
6, owing to introduce at random, its algorithm speed just becomes key factor, best solution is to adopt hardware one randomizer, also can obtain random number etc. by the random cells of access computer internal memory, because between each grid cell is fully independently, so be fit to do parallel processing with a plurality of processors, this method itself need not be netted the angle technology in addition, thereby makes this method have more superiority on linked network speed, slice speed.
Further specify method of the present invention below in conjunction with an embodiment step:
1) Z of scope at random, screening screen density L, the subnet point area lower limit S that subnet is counted out in the user input unit grid
M, subnet point area upper limit S
NAnd dot shape;
2) calculate the S of minimum area unit that constitutes subnet point by screening screen density L
i, S
i=1/ (L
2* 256), and by subnet point area lower limit S
MCalculate the N of lower limit at random of subnet point area
M=S
M/ S
i, N
MRound numbers;
3) by grid cell densitometer operator site total area M, M=A% * (1/L
2), A% is the gray scale percent value of this grid cell punishment look, be in the grid cell surface coverage in theory;
4) in the Z of the scope at random value that subnet is counted out, produce a random number as the subnet of this grid cell K that counts by randomizer;
5) by subnet point area upper limit S
NDetermine the N of the upper limit at random of subnet point area
A, N
A=S
N/ S
i, N
ARound numbers;
6) subnet being put total area M random division is K sub-dot area, makes each subnet point area at N
MAnd N
AIn the scope, promptly each subnet point area at random is N
MTo N
AThe individual sub-site S of minimum area unit
i7) in the limited range of position, produce the position of each subnet point by randomizer.
This FM and AM netting method has carried out experimental verification with the following method, gets network point distribution figure with laser printer earlier, takes a picture then and makes film, narrows down to be equivalent to 150Lpi extension screen density, observes the moir phenomenon with the stack between the film.
Fig. 1 is 50% homalographic tradition network point distribution figure;
Fig. 2 is area tradition network point distribution figure at random;
Fig. 3 carries out at random the position, site of accompanying drawing 1;
Fig. 4 is that the site with accompanying drawing 1 is divided into four sub-sites, and each subnet point position at random;
Fig. 5 is that the site with accompanying drawing 1 is divided into one, four homalographic subnet point at random, and the position at random;
Fig. 6 is that the site with accompanying drawing 1 is divided into one, two, three, four homalographic subnet point at random, and the position at random.
Fig. 7 is divided into two, three, four homalographic subnet points at random to the site, and the position at random.
Comparison diagram 1, Fig. 2 can find to have strong moir Lou Lou patterns among Fig. 1, and scheme 2 are not strong, and Fig. 2 is obviously not as Fig. 1 rule, thereby moir Lou Lou patterns is also not obvious. Fig. 3 extremely experiment shown in Figure 7 shows, if can solve 50% homalographic site not That line, other are no problem then. Fig. 3 carries out at random the position, site of Fig. 1, because The site is very big, so amplitude is little, experimental results show that moir Lou Lou patterns weakens a little, but not clear Aobvious, Fig. 4 is divided into four sub-networks to the site of Fig. 1, each sub-network position with Machine, experimental results show that moir Lou Lou patterns especially rose spot size reduce half, be equivalent to screening The line number doubles, and illustrates that this method is with practical value. Among Fig. 5 with Fig. 1's The site is divided into one, four homalographic sub-network at random, the position at random, Fig. 6 is with Fig. 1 The site be divided at random one, two, three, four homalographic sub-network, the position is at random; Fig. 7 is divided into two, three, four homalographic sub-networks, position at random with the site of Fig. 1 At random, from above-mentioned experimental result, effect is all good, and it is existing almost to can't see moir Lou Lou patterns Resemble, also needn't net the angle and stagger, especially the best results of Fig. 6, Fig. 7.
The difference of this method and amplitude modulation screening is:
1, represent the site by number sub-network at random, but not a site;
2, the position of sub-network is at random, rather than fixing;
3, can no longer adopt the net angle certain angle that staggers for general quality requirement Screening technology;
The difference of this method and frequency-modulation screening is:
1, the site is made up of the sub-network of random number, and the site in the frequency-modulation screening Number is determined by gray scale;
2, the site is made up of area sub-network at random, rather than in the frequency-modulation screening by etc. Area point forms;
3, the subnet point has the restriction of maximum, minimum area, and minimum area is decided by the feasibility of typography, rather than is difficult to the particulate point realized in the modulating net on the minimum technology.
In press the moir of Chu Xianing, rose spot are a kind of well-regulated phenomenons, all well-regulated phenomenons are all caused by well-regulated internal factor, thoroughly eliminate well-regulated phenomenon, must eliminate well-regulated internal cause, adopt random technology, the basis of the inventive method promptly is this.
In sum, this net hanging method has tangible difference with traditional amplitude modulation screening and frequency-modulation screening, is seen that by the film that experiment generates the size of site, number, the equal stochastic distribution in position have distinct feature.
Claims (4)
1, a kind of FM and AM netting method, with the coloured image master copy color-dividing is green grass or young crops, product, Huang, black four table images of throwing the net, the ratio that accounts for the grid cell area with subnet point area in each grid cell of each grid image is controlled gray shade scale and is counted G, it is characterized in that comprising:
1) Z of value range at random, screening screen density L, the subnet point area lower limit S that subnet is counted out in the user input unit grid
M, subnet point area upper limit S
NAnd dot shape;
2) count G by screening screen density L and gray shade scale and calculate the S of minimum area unit that constitutes subnet point
i, S
i=1/ (L
2* G), G is decided to be 256, and by subnet point area lower limit S
MCalculate subnet point area lower limit N at random
M=S
M/ S
i, N
MRound numbers;
3) by grid cell densitometer operator site total area M, M=A% * (1/L
2), A% is a theoretic surface coverage in the grid cell;
4) in the Z of the scope at random value that subnet is counted out, produce a random number as the subnet of this grid cell K that counts by randomizer;
5) by subnet point area upper limit S
NDetermine subnet point area upper limit N at random
A, N
A=S
N/ S
i, N
ARound numbers;
6) subnet being put total area M random division is K sub-dot area, makes each subnet point area at N
MAnd N
AIn the scope;
7) be the border with the grid cell but producing each subnet point position in grid cell by randomizer in the limited range of nonoverlapping position.
2, a kind of FM and AM netting method according to claim 1 is characterized in that: described subnet counts out at random that value range Z is 1-10; The lower limit of described subnet point area is by the decision of typography level, and the upper limit of described subnet point area is to be determined by printing quality.
3, a kind of FM and AM netting method according to claim 1 is characterized in that: described dot shape is circular, square, rhombus, ellipse.
4, a kind of FM and AM netting method according to claim 1 is characterized in that: described subnet is put total area M random division is that K sub-dot area is the division methods that adopts homalographic.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN95106737A CN1062079C (en) | 1995-06-21 | 1995-06-21 | FM and AM netting method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN95106737A CN1062079C (en) | 1995-06-21 | 1995-06-21 | FM and AM netting method |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1138524A CN1138524A (en) | 1996-12-25 |
| CN1062079C true CN1062079C (en) | 2001-02-14 |
Family
ID=5076002
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN95106737A Expired - Fee Related CN1062079C (en) | 1995-06-21 | 1995-06-21 | FM and AM netting method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1062079C (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1312532C (en) * | 2004-12-20 | 2007-04-25 | 北京北大方正电子有限公司 | Seamless mixed lattice point net hanging method used for gravure plating |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100377566C (en) * | 2005-10-26 | 2008-03-26 | 北京北大方正电子有限公司 | Frequency-modulated and amplitude modulation mixed half tone image processing method on multiposition imaging depth equipment |
| CN102098416B (en) * | 2009-12-11 | 2013-03-13 | 北大方正集团有限公司 | Frequency modulation and amplitude modulation network control method and device |
| KR20130094685A (en) * | 2010-08-05 | 2013-08-26 | 가부시키가이샤 씽크. 라보라토리 | Gravure printing plate and method for producing gravure printing plate |
| CN102023475B (en) * | 2010-10-13 | 2012-07-04 | 北京方嘉彩色印刷有限责任公司 | High-precision frequency-modulated screen dot printing process |
| WO2012061974A1 (en) * | 2010-11-09 | 2012-05-18 | 北京中科纳新印刷技术有限公司 | Platemaking method and device of storing and outputting information by unit dot matrix |
| CN102189739A (en) * | 2011-03-22 | 2011-09-21 | 昆山金利表面材料应用科技股份有限公司 | Mesh point structure of screen printing film |
| CN102700235A (en) * | 2012-06-08 | 2012-10-03 | 广州市人民印刷厂 | Multi-screen printing process |
| CN111746165A (en) * | 2020-07-15 | 2020-10-09 | 上海紫恩数码科技有限公司 | Printing method for improving printing mouth phenomenon of flexographic plate printing |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3197558A (en) * | 1960-04-01 | 1965-07-27 | Petits Fils De Leonard Danel | Process for the reproduction of continuous tone pictures |
| GB2174265A (en) * | 1985-03-20 | 1986-10-29 | Canon Kk | Half-tone imaging process |
| DE3934867A1 (en) * | 1988-10-19 | 1990-04-26 | Hitachi Koki Kk | OPTICAL SCANNER WITH A COMPOSITE SPOT-LIGHTING SOURCE |
| EP0620673A1 (en) * | 1993-04-16 | 1994-10-19 | Agfa-Gevaert N.V. | Method for making a lithographic printing plate |
| EP0639023A1 (en) * | 1993-08-13 | 1995-02-15 | Agfa-Gevaert N.V. | Frequency-modulation halftone screen and method for making same |
-
1995
- 1995-06-21 CN CN95106737A patent/CN1062079C/en not_active Expired - Fee Related
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3197558A (en) * | 1960-04-01 | 1965-07-27 | Petits Fils De Leonard Danel | Process for the reproduction of continuous tone pictures |
| GB2174265A (en) * | 1985-03-20 | 1986-10-29 | Canon Kk | Half-tone imaging process |
| DE3934867A1 (en) * | 1988-10-19 | 1990-04-26 | Hitachi Koki Kk | OPTICAL SCANNER WITH A COMPOSITE SPOT-LIGHTING SOURCE |
| EP0620673A1 (en) * | 1993-04-16 | 1994-10-19 | Agfa-Gevaert N.V. | Method for making a lithographic printing plate |
| EP0639023A1 (en) * | 1993-08-13 | 1995-02-15 | Agfa-Gevaert N.V. | Frequency-modulation halftone screen and method for making same |
Non-Patent Citations (1)
| Title |
|---|
| 1994年8,9期总第182,183《印刷技术》 1994.8.1 孙立博《百花齐放的POSTSERIPT挂网技术》上 下 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1312532C (en) * | 2004-12-20 | 2007-04-25 | 北京北大方正电子有限公司 | Seamless mixed lattice point net hanging method used for gravure plating |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1138524A (en) | 1996-12-25 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1062079C (en) | FM and AM netting method | |
| US5074596A (en) | Currency paper, especially bank note, with a safety design and process for producing it | |
| DE69425244T2 (en) | Tone-dependent rosette structures in multi-layer halftone screening using phase modulation | |
| DE69320293T2 (en) | Method and device for generating halftone screened images | |
| DE69527675T2 (en) | Multi-level halftone screening with grouped dots and lines for electrographic color printing | |
| DE3004749A1 (en) | DEVICE AND METHOD FOR THE DIGITALLY CONTROLLED PRODUCTION OF PRINTING FORMS USING A LASER | |
| DE69322914T2 (en) | Raster filter and generating device and method therefor | |
| EP1285528B1 (en) | Multiple tone level rasterization with rasters screens of any width and angle | |
| DE68921420T2 (en) | Method and device for recording halftone halftone images. | |
| EP1528987B2 (en) | Data carrier | |
| WO1992010056A1 (en) | Process for generating and storing digitised density thresholds for defining the grid of a half-tone image | |
| EP0612181A1 (en) | Method and appartus for converting grey scale values into binary values | |
| US6687021B1 (en) | Method for digitally rasterizing half-tone images with rasters of any width and angle | |
| US7268920B1 (en) | Halftone patterns | |
| US11825056B2 (en) | System and method for obtaining a uniform ink layer | |
| JP3085911B2 (en) | Screen printing method using a rotating screen | |
| DE102016121000B4 (en) | Process for decorating containers and device for carrying out the process | |
| DE102005052874B4 (en) | Method for generating a threshold value matrix for a frequency-modulated screening | |
| CN1359030A (en) | Seamless screening method for gravure printing | |
| DE4038057C2 (en) | Process for the generation and storage of digitized density threshold values for screening a halftone image template | |
| DE2025609A1 (en) | Screen for prod of printing forms | |
| EP1196295B1 (en) | Form of a printing element in an offset printing process | |
| EP1340366A1 (en) | Method for representing the halftone of an image and image treatment device and printing device for carrying out said method | |
| DE10261004B4 (en) | Method for applying random numbers in the screening of image data | |
| DE1803707A1 (en) | Autotype half tone screen for duplex and - colour printing |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C19 | Lapse of patent right due to non-payment of the annual fee | ||
| CF01 | Termination of patent right due to non-payment of annual fee |