CN107452042B - A kind of halftoning apparatus spectral characteristic model optimization method and system - Google Patents
A kind of halftoning apparatus spectral characteristic model optimization method and system Download PDFInfo
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Abstract
A kind of halftoning apparatus spectral characteristic model optimization method and system, can effectively realize the optimization of Cellular compartment form You Er Nelson's spectrum Nie Gebaier model characteristics process, including prepare Forward modeling sample and measure its spectral reflectivity information；Full mass colour combination is constructed respectively and closes forward model without black ink colour cell；Contrast lightness threshold is predicted using forward model is closed without black ink colour cell, and equipment colour gamut is divided into high light, middle tone and shadow three parts；For any color spectrum reflectivity information to be copied, seeks it and correspond to lightness, and its described contrast is judged；For high light color, reversed color separation is carried out to forward model is closed without black ink colour cell；For shadow color, reversed color separation is carried out to full mass colour combination forward model；For middle tone color, the reversed color separation of forward model progress is closed to full mass colour and without black ink colour cell respectively, and turn to principle so that reversed model accuracy is optimal, determine final color separation.
Description
Technical field
The invention belongs to halftone color reproduction technology fields, and in particular to a kind of halftoning apparatus spectral characteristic model
Optimization method and system.
Background technique
Halftone color reproduction technology is the mainstream technology in current colors of image duplication field, passes through halftoning ink dot
Density arrangement and overlapping, realize the accurate duplication of color.In the art, it is color that halftoning apparatus, which characterizes model construction,
Key link in reproduction process substantially constructs the biaxial stress structure model of halftone color information to equipment ink amount information.
Wherein, Forward modeling (i.e. Colours model) is known as by the modeling process of equipment ink amount information to halftone color information, by
The modeling process (i.e. the inversion process of forward model) of halftone color information to equipment ink amount information is known as reversed modeling (also known as
For colour separating model).
Halftoning apparatus chromatic characteristicization modeling based on spectrum, can overcome conventional chromaticity characterization to build to greatest extent
The intrinsic metamerism problem of mold process, thus realize higher levels of Color Replication, therefore it is grinding for presently relevant field
Study carefully hot spot.Wherein, in halftoning apparatus spectral characteristic research field, the modified spectrum of You Er Nelson of Cellular compartment form
Nie Gebaier model (Cellular Yule-Nielsen spectral Neugebauer model, hereinafter referred to as CYNSN mould
Type) it is the model I with degree of precision generally acknowledged at present, it is widely used in this field.
However, causing since the black ink for commonly using halftoning apparatus common configuration has stronger absorbing properties
The shadow sample of CYNSN model is significantly more than high light sample, so cause bright area chromatic characteristic precision
Relatively poor problem.Further, since tri- color of CMY is folded in conventional four-color (green, product, yellow, black, i.e. CMYK) halftoning apparatus
Print equally will cause grey or black sample, therefore such equipment is when constructing the characterization process based on CYNSN model, above-mentioned bright
Adjust error problem more significant.
It at this stage, is restricted by subjective and objective factors such as theoretical method levels, is ground currently based on the characterization of CYNSN model
Study carefully field (containing all kinds of Optimized models), it is also generally existing that above-mentioned high light characterizes the relatively low problem of precision.
Summary of the invention
The purpose of the present invention is to solve problems described in background technique, propose a kind of half color towards CYNSN model
Adjust equipment spectral characteristic model optimization method and system.
The technical scheme is that providing a kind of halftoning apparatus spectral characteristic model optimization towards CYNSN model
Method, comprising the following steps:
Step 1, it is sampled in halftoning apparatus color space, and prepares halftone color sample；
Step 2, using color measuring apparatus, each sample spectral reflectivity information in obtaining step 1 is measured；
Step 3, in step 2 based on measurement gained sample spectrum reflectivity data, half color for being n for mass colour quantity
Adjusting system constructs CYNSN model Fn；
Step 4, in step 2 based on measurement gained sample spectrum reflectivity data, for half that mass colour quantity is n-1
Color Shade System constructs CYNSN model Fn-1, the halftone system that the mass colour quantity is n-1 is without black ink；
Step 5, F constructed by step 4 is utilizedn-1Model prediction high light and middle tone distinguish threshold value Llm, middle tone and shadow
Distinguish threshold value Lmd, halftoning apparatus colour gamut is divided into high light, middle tone and shadow three parts；
Step 6, for any color to be copied, its color spectrum reflectivity information is converted to CIELAB color space,
And obtain its lightness information L；
Step 7, contrast judgement is carried out to color to be copied according to lightness information L described in step 6, and determines final point
Color.
Moreover, in the step 5, the device space for being 30 for ink magnitude each in the halftone system of n-1 with mass colour quantity
Point brightness value corresponding to CIELAB color space is that high light and middle tone distinguish threshold value Llm, it is the half of n-1 with mass colour quantity
Device space point brightness value corresponding to CIELAB color space that each ink magnitude is 70 in Color Shade System is middle tone and dark
It adjusts and distinguishes threshold value Lmd。
Moreover, the implementation of the step 7 is as follows,
If L > Llm, color to be copied belongs to bright area, using Fn-1Model carries out reversed color separation；If L < Lmd, to be copied
Color belongs to shadow region, using FnModel carries out reversed color separation；If Lmd<L<Llm, color to be copied belongs to middle tone region, together
Shi Caiyong FnModel and Fn-1Model carries out reversed color separation, and turns to principle so that reversed Color separating accuracy is optimal, determines final color separation
Value.
Moreover, the color measuring apparatus in the step 2 is spectrophotometer.
The halftoning apparatus spectral characteristic model optimization system towards CYNSN model that the present invention also provides a kind of, including
With lower module:
Halftoning sample preparation module for being sampled in halftoning apparatus color space, and prepares halftoning color
Color sample；
Color measuring module, for utilizing color measuring apparatus, measurement obtains each sample in halftoning sample preparation module
Spectral reflectivity information；
Full mass colour Forward modeling module, for measure gained sample spectrum reflectivity data in color measuring module as base
Plinth constructs CYNSN model F for the halftone system that mass colour quantity is nn；
Non-black mass colour Forward modeling module, for measure gained sample spectrum reflectivity data in color measuring module
Based on, CYNSN model F is constructed for the halftone system that mass colour quantity is n-1n-1, the mass colour quantity is half color of n-1
Adjusting system is free of black ink；
Contrast division module, for utilizing F constructed by non-black Forward modeling modulen-1Model prediction high light and centre
It adjusts and distinguishes threshold value Llm, middle tone and shadow distinguish threshold value Lmd, halftoning apparatus colour gamut is divided into high light, middle tone and shadow
Three parts；
Color conversion module, for for any color to be copied, by its color spectrum reflectivity information convert to
CIELAB color space, and obtain its lightness information L；
Final color separation module, for carrying out contrast to color to be copied according to lightness information L described in color conversion module
Judgement, and determine final color separation.
It for ink magnitude each in the halftone system of n-1 is 30 to set with mass colour quantity moreover, in the contrast division module
Standby spatial point brightness value corresponding to CIELAB color space is that high light and middle tone distinguish threshold value Llm, it is n- with mass colour quantity
Device space point brightness value corresponding to CIELAB color space that each ink magnitude is 70 in 1 halftone system is middle tone
And shadow distinguishes threshold value Lmd。
Moreover, in the final color separation module, if L > Llm, color to be copied belongs to bright area, using Fn-1Model carries out
Reversed color separation；If L < Lmd, color to be copied belongs to shadow region, using FnModel carries out reversed color separation；If Lmd<L<Llm, to multiple
Color processed belongs to middle tone region, while using FnModel and Fn-1Model carries out reversed color separation, and most with reversed Color separating accuracy
It is optimized for principle, determines final color separation value.
Moreover, the color measuring apparatus in the color measuring module is spectrophotometer.
Compared with prior art, beneficial effects of the present invention are as follows:
A kind of halftoning apparatus spectral characteristic model optimization technical solution proposed by the present invention, to optimize CYNSN model
For the purpose of characterizing process bright area precision, is individually constructed using non-black mass colour system and characterize model as means, be not necessarily to
Under conditions of extra samples sample, effectively realizes the whole of CYNSN model characteristics precision and promoted, and is easy to implement, half
Tinge reproduction technology field has stronger applicability.Since technical solution of the present invention has important application meaning, by
Multiple project supports: 1. project of national nature science fund project, 61505149,2. Wuhan City youth morning twilight talent plan
2016070204010111,3. Hubei Province Nsfc Projects 2015CFB204,4 Shenzhen's basic research projects
JCYJ20150422150029093.Technical solution of the present invention is protected, China's relevant industries will be competed leading in the worldly
Position is of great significance.
Detailed description of the invention
Fig. 1 is the flow chart of the embodiment of the present invention.
Specific embodiment
In conjunction with attached drawing, the embodiment of the present invention is provided and is described in detail below.
A kind of halftoning apparatus spectral characteristic model optimization technical solution that embodiment as shown in Figure 1 provides, with optimization
For the purpose of CYNSN model characteristics process bright area precision, is individually constructed using non-black mass colour system and characterize model as hand
Section effectively realizes the whole of CYNSN model characteristics precision and is promoted.The method it is ideal solve background technology part
Described problem so as to improve the characterization precision of halftoning apparatus, and then guarantees the color of halftone color replicated product
Quality, and it is easy to implement, there is stronger applicability.
For embodiment is using tetra- color ink-jet printer of certain brand CMYK and certain brand ink-jet printing media, to the present invention
A kind of halftoning apparatus spectral characteristic model optimization technical solution referred to is introduced.It should be noted that the present invention is simultaneously
It is not limited to equipment and paper media mentioned by the studies above, for other equipment and medium, this method is equally applicable.
Technical solution of the present invention can be realized by those skilled in the art using computer software technology automatic when being embodied
Operation.Embodiment provide method flow the following steps are included:
1) it is sampled in halftoning apparatus color space, and prepares halftone color sample.
Embodiment carries out 5 grades of uniform samplings to each color dimension of tetra- colour space of CMYK, i.e., monochromatic black magnitude range is 0-
100,0,25,50,75,100 are taken, can so collect 5 × 5 × 5 × 5=625 color color lump sample as CYNSN model
Modeling sample, then, prepare each 11 grades of step-wedges (0,10,20,30,40...100) of mass colour of CMYK, for constructing dot gain
Curve.442 random coloration samples are prepared, for training neural network, and then construct BPn-CYNSN model.The model is this
One of area research CYNSN Optimized model the most advanced is the prior art, and detail can be found in bibliography:
Liu Q,Wan X,Xie D.Optimization of spectral printer modeling based on
a modified cellular Yule Nielsen spectral Neugebauer model.J Opt Soc Am
A.2014；31(6):1284-94.
2) using color measuring apparatus such as spectrophotometers, measurement obtains each sample spectral reflectivity information in 1).
Embodiment uses certain brand automatically scanning formula spectrophotometer, and it is a to amount to 1111 (625+442+4*11) in measurement 1)
The spectral reflectivity information of sample.
3) based on measuring gained sample spectrum reflectivity data in 2), the halftone system for being n for mass colour quantity
Construct CYNSN model Fn。
Embodiment is based on measuring gained color spectrum reflectivity data in 2), for tetra- color model of CMYK, building
BPn-CYNSN model (as Fn).The model is that one of CYNSN Optimized model the most advanced is studied in this field, is existing skill
Art, detail can be found in bibliography:
Liu Q,Wan X,Xie D.Optimization of spectral printer modeling based on
a modified cellular Yule Nielsen spectral Neugebauer model.J Opt Soc Am
A.2014；31(6):1284-94.
It 4) is that n-1 (is free of black ink for mass colour quantity based on measuring gained sample spectrum reflectivity data in 2)
Water) halftone system construct CYNSN model Fn-1, the halftone system that the mass colour quantity is n-1 is without black ink；
Embodiment is chosen in 1) in 1111 samples, and the sample point of all K=0 constructs CYNSN model.Wherein, it builds herein
Apperance originally includes 11 grades of step-wedges (0,10,20,30,40...100) of each mass colour of CMY and 5 × 5 × 5=125, the space CMY color
Color lump sample.In conjunction with spectral information of the above-mentioned sample obtained in 2), CYNSN model (i.e. F is constructedn-1Model).Wherein,
CYNSN model construction is the prior art, reference can be made to bibliography:
Wang B,Xu H,Luo MR,Guo J.Spectral-based color separation method for a
multi-ink printer.Chinese Optics Letters.2011；9(6):063301.
Liu Q,Wan X,Xie D.Optimization of spectral printer modeling based on
a modified cellular Yule Nielsen spectral Neugebauer model.J Opt Soc Am
A.2014；31(6):1284-94.
5) F constructed by 4) is utilizedn-1Model prediction high light and middle tone distinguish threshold value Llm, middle tone and shadow distinguish threshold
Value Lmd, halftoning apparatus colour gamut is divided into high light, middle tone and shadow three parts, wherein (be free of for n-1 with mass colour quantity
Black ink) halftone system in each black magnitude be 30 device space point in CIELAB color space (D50/2 coloration item
Part) corresponding to brightness value be that high light and middle tone distinguish threshold value Llm, it is half color of n-1 (being free of black ink) with mass colour quantity
Device space point brightness value corresponding to CIELAB color space (D50/2 chrominance requirements) that each ink magnitude is 70 in adjusting system
Threshold value L is distinguished for middle tone and shadowmd。
Embodiment is with the F constructed by 4)n-1Model prediction contrast threshold value Llm, Lmd, by Fn-1(C=30, M=known to prediction
30, Y=30, K=0) sample point corresponds to spectral information brightness value corresponding to CIELAB color space (D50/2 chrominance requirements)
Llm=59, (C=70, M=70, Y=70, K=0) sample point corresponds to spectral information in CIELAB color space (D50/2 coloration item
Part) corresponding to brightness value Lmd=39, above-mentioned is contrast division threshold value in embodiment.
6) for any color spectrum reflectivity information to be copied, its color is believed first with color science fundamental formular
Breath is converted to CIELAB color space (D50/2 chrominance requirements), and obtains its lightness information L；
Embodiment respectively generates 50 sample points in the space CMYK and CMY at random and prepares its color sample, and with this 100
Color sample is sample to be copied, is tested to method proposed by the invention.Wherein, by spectral reflectivity information convert to
CIELAB color space (D50/2 chrominance requirements), and obtaining its lightness information is the prior art, for details, reference can be made to:
Schanda J.CIE colorimetry:Wiley Online Library；2007.
7) contrast judgement is carried out to color to be copied according to lightness information L described in 6), and determines final color separation.Wherein,
If L > Llm, i.e., color to be copied belongs to bright area, then using Fn-1Model carries out reversed color separation；If L < Lmd, i.e., color to be copied
Coloured silk belongs to shadow region, then uses FnModel carries out reversed color separation；If Lmd<L<Llm, i.e., color to be copied belongs to middle tone region,
F is then used simultaneouslynModel and Fn-1Model carries out reversed color separation, and turns to principle so that reversed Color separating accuracy is optimal, determines
Final color separation value.
In embodiment, for 100 color samples 6) referred to, if L > 59, i.e., color information to be copied belongs to high light area
Domain then uses Fn-1Model (tri- color CYNSN model of CMY) carries out reversed color separation；If L < 39, i.e., color information to be copied belongs to secretly
Region is adjusted, then uses FnModel ((tetra- color BPn-CYNSN model of CMYK)) carries out reversed color separation；If 39 < L < 59, i.e., color to be copied
Multimedia message belongs to middle tone region, then uses F simultaneouslynModel and Fn-1Model carries out reversed color separation, and with reversed color separation
Precision is optimal to turn to principle, selects final color separation value.Wherein, reversed Color separating accuracy is existing concept, and meaning is reversely to divide
Color ink magnitude brings the mistake between forward model prediction gained spectral reflectivity information and practical spectral reflectivity information to be copied into
Difference, for details, reference can be made to documents:
Wang B,Xu H,Luo MR,Guo J.Spectral-based color separation method for a
multi-ink printer.Chinese Optics Letters.2011；9(6):063301.
Liu Q,Wan X,Xie D.Optimization of spectral printer modeling based on
a modified cellular Yule Nielsen spectral Neugebauer model.J Opt Soc Am
A.2014；31(6):1284-94.
Experiments verify that for 100 color samples 6) referred to, it is bright based on the characterization model that the present invention constructs
Adjust precision are as follows: (under identical modeling sample quantity, traditional CYNSN characterizes model essence by RMS=0.009, CIEDE2000=0.96
Degree is RMS=0.017, CIEDE2000=1.48)；Precision is adjusted among it are as follows: RMS=0.008, CIEDE2000=0.83 (phase
With under modeling sample quantity, it is RMS=0.008, CIEDE2000=0.96 that traditional CYNSN, which characterizes model accuracy)；Its shadow
Precision are as follows: RMS=0.004, CIEDE2000=0.69 are (since traditional CYNSN model characteristicsization have had ideal shadow
Precision, the present invention do not optimize this region).
It can be seen that the present invention has ideal effect in optimization light characteristic precision aspect.In addition it should be pointed out that
, why the present invention in middle tone takes FnModel and Fn-1The method of model color separation optimizing, is in order to avoid due to not
The problem of jumping with contrast Near Threshold contrast caused by model color separation characteristic difference.
The halftoning apparatus spectral characteristic model optimization system towards CYNSN model that the present invention also provides a kind of, including
With lower module:
Halftoning sample preparation module for being sampled in halftoning apparatus color space, and prepares halftoning color
Color sample；
Color measuring module, for using color measuring apparatus such as spectrophotometers, measurement to obtain halftoning sample preparation
Each sample spectral reflectivity information in module；
Full mass colour Forward modeling module, for measure gained color spectrum reflectivity data in color measuring module as base
Plinth constructs CYNSN model F for the halftone system that mass colour quantity is nn；
Non-black mass colour Forward modeling module, for measure gained color spectrum reflectivity data in color measuring module
Based on, CYNSN model F is constructed for the halftone system that mass colour quantity is n-1 (being free of black ink)n-1, the mass colour number
The halftone system that amount is n-1 is free of black ink；
Contrast division module, for utilizing F constructed by non-black Forward modeling modulen-1Model prediction high light and centre
It adjusts and distinguishes threshold value Llm, middle tone and shadow distinguish threshold value Lmd, halftoning apparatus colour gamut is divided into high light, middle tone and shadow
Three parts；
Color conversion module, it is substantially public using color science for being directed to any color spectrum reflectivity information to be copied
Formula converts its color information to CIELAB color space (D50/2 chrominance requirements), and obtains its lightness information L；
Final color separation module, for carrying out contrast to color to be copied according to lightness information L described in color conversion module
Judgement, and determine final color separation.
Wherein, in contrast division module, each ink amount in the halftone system with mass colour quantity for n-1 (being free of black ink)
Device space point brightness value corresponding to CIELAB color space (D50/2 chrominance requirements) that value is 30 is high light and middle tone
Distinguish threshold value Llm, each black magnitude is 70 in the halftone system with mass colour quantity for n-1 (be free of black ink) the device space
Point brightness value corresponding to CIELAB color space (D50/2 chrominance requirements) is that middle tone and shadow distinguish threshold value Lmd。
Wherein, in final color separation module, if L > Llm, i.e., color information to be copied belongs to bright area, then using Fn-1Model
Carry out reversed color separation；If L < Lmd, i.e., color information to be copied belongs to shadow region, then using FnModel carries out reversed color separation；If
Lmd<L<Llm, i.e., color information to be copied belongs to middle tone region, then simultaneously using FnModel and Fn-1Model carries out anti-
Principle is turned to color separation, and with reversed Color separating accuracy is optimal, determines final color separation value.
Each module specific implementation is corresponding with each step, and it will not go into details by the present invention.
Specific embodiment described herein is only an example for the spirit of the invention.The neck of technology belonging to the present invention
The technical staff in domain can make various modifications or additions to the described embodiments or replace by a similar method
In generation, however, it does not deviate from the spirit of the invention or beyond the scope of the appended claims.
Claims (6)
1. a kind of halftoning apparatus spectral characteristic model optimization method, which comprises the following steps:
Step 1, it is sampled in halftoning apparatus color space, and prepares halftone color sample；
Step 2, using color measuring apparatus, each sample spectral reflectivity information in obtaining step 1 is measured；
Step 3, in step 2 based on measurement gained sample spectrum reflectivity data, the halftoning system for being n for mass colour quantity
System building CYNSN model Fn；
Step 4, in step 2 based on measurement gained sample spectrum reflectivity data, the halftoning for being n-1 for mass colour quantity
System constructs CYNSN model Fn-1, the halftone system that the mass colour quantity is n-1 is without black ink；
Step 5, F constructed by step 4 is utilizedn-1Model prediction high light and middle tone distinguish threshold value Llm, middle tone and shadow distinguish
Threshold value Lmd, halftoning apparatus colour gamut is divided into high light, middle tone and shadow three parts；
Step 6, for any color to be copied, its color spectrum reflectivity information is converted to CIELAB color space, and is obtained
Obtain its lightness information L；
Step 7, contrast judgement is carried out to color to be copied according to lightness information L described in step 6, and determines final color separation, tool
Body implementation are as follows: if L > Llm, color to be copied belongs to bright area, using Fn-1Model carries out reversed color separation；If L < Lmd, to
Duplication color belongs to shadow region, using FnModel carries out reversed color separation；If Lmd<L<Llm, color to be copied belongs to middle tone area
Domain, while using FnModel and Fn-1Model carries out reversed color separation, and turns to principle so that reversed Color separating accuracy is optimal, determines most
Whole color separation value.
2. a kind of halftoning apparatus spectral characteristic model optimization method according to claim 1, it is characterised in that:
In the step 5, with mass colour quantity in the halftone system of n-1 it is each ink magnitude be 30 device space point in CIELAB
Brightness value corresponding to color space is that high light and middle tone distinguish threshold value Llm, with mass colour quantity in the halftone system of n-1
Device space point brightness value corresponding to CIELAB color space that each ink magnitude is 70 is that middle tone and shadow distinguish threshold value
Lmd。
3. a kind of halftoning apparatus spectral characteristic model optimization method according to claim 2, it is characterised in that: described
Color measuring apparatus in step 2 is spectrophotometer.
4. a kind of halftoning apparatus spectral characteristic model optimization system, which is characterized in that comprise the following modules:
Halftoning sample preparation module for being sampled in halftoning apparatus color space, and prepares halftone color sample
This；
Color measuring module, for utilizing color measuring apparatus, measurement obtains each sample spectrum in halftoning sample preparation module
Reflectivity information；
Full mass colour Forward modeling module is used for based on measurement gained sample spectrum reflectivity data in color measuring module,
CYNSN model F is constructed for the halftone system that mass colour quantity is nn；
Non-black mass colour Forward modeling module, for measure gained sample spectrum reflectivity data in color measuring module as base
Plinth constructs CYNSN model F for the halftone system that mass colour quantity is n-1n-1, the mass colour quantity is the halftoning system of n-1
System is free of black ink；
Contrast division module, for utilizing F constructed by non-black Forward modeling modulen-1Model prediction high light and middle tone area
Divide threshold value Llm, middle tone and shadow distinguish threshold value Lmd, halftoning apparatus colour gamut is divided into high light, middle tone and shadow three
Point；
Color conversion module, for for any color to be copied, its color spectrum reflectivity information to be converted to CIELAB face
The colour space, and obtain its lightness information L；
Final color separation module, for carrying out contrast judgement to color to be copied according to lightness information L described in color conversion module,
And determine final color separation；In the final color separation module, if L > Llm, color to be copied belongs to bright area, using Fn-1Model into
The reversed color separation of row；If L < Lmd, color to be copied belongs to shadow region, using FnModel carries out reversed color separation；If Lmd<L<Llm, to
Duplication color belongs to middle tone region, while using FnModel and Fn-1Model carries out reversed color separation, and with reversed Color separating accuracy
It is optimal to turn to principle, determine final color separation value.
5. a kind of halftoning apparatus spectral characteristic model optimization system according to claim 4, it is characterised in that:
In the contrast division module, the device space point for being 30 for ink magnitude each in the halftone system of n-1 with mass colour quantity
The brightness value corresponding to CIELAB color space is that high light and middle tone distinguish threshold value Llm, it is half color of n-1 with mass colour quantity
Device space point brightness value corresponding to CIELAB color space that each ink magnitude is 70 in adjusting system is middle tone and shadow
Distinguish threshold value Lmd。
6. a kind of halftoning apparatus spectral characteristic model optimization system according to claim 5, it is characterised in that: described
Color measuring apparatus in color measuring module is spectrophotometer.
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| CN108462863B (en) * | 2018-02-11 | 2020-06-05 | 上海健康医学院 | Display equipment color space conversion method based on composite model |
| CN113546874B (en) * | 2021-07-15 | 2023-04-11 | 厦门强力巨彩光电科技有限公司 | SMT PCB ink color classification method |
| CN113692089B (en) * | 2021-07-29 | 2023-07-11 | 中山市小兀照明科技有限公司 | Light source control method and device and computer readable storage medium |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102160046A (en) * | 2008-08-27 | 2011-08-17 | 太阳化学公司 | Automated ink color matching of solids and tones |
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| Title |
|---|
| Optimization of spectral printer modeling based on a modified cellular Yule–Nielsen spectral Neugebauer model;Liu Q 等;《JOSA A》;20140630;第31卷(第6期);第1284-1294页 * |
| 半色调设备光谱特性描述方法研究;张春妹;《中国优秀硕士学位论文全文数据库 工程科技Ⅰ辑》;20130515;第B024-87页 * |
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