CN104760418B - Mass colour fast control method and control system thereof for digital printer - Google Patents

Abstract

The invention provides a kind of digital printer mass colour fast control method and control system thereof, described control method comprises: the woven designs pattern of Real-time Collection after ink-jet apparatus ink-jet; The woven designs pattern collecting is sampled, obtain sampled data; Receive sampled data and according to sampled data reconstruct woven designs pattern, the woven designs pattern after reconstruct and the floral designs template prestoring contrasted, forming compare error; According to compare error, adopt closed-loop automatic control method to regulate the mass colour of ink-jet apparatus ejection, reduce the woven designs pattern after ink-jet and the floral designs template that prestores between compare error. Digital printer provided by the invention can increase substantially the stamp speed of digital printer by mass colour fast control method and control system, adopt closed-loop automatic control method to make the woven designs pattern that printing machine prints off there is higher precision simultaneously, greatly improved the production efficiency of printing machine and saved the energy.

Description

Mass colour fast control method and control system thereof for digital printer

Technical field

The present invention relates to automation field, and be particularly related to a kind of digital printer mass colour fast control method andControl system.

Background technology

Stamp is an important procedure in textile industry, and it not only can produce for consumer provides multicoloured weavingProduct, but also can greatly improve the surcharge of textile. The property indices of stamp directly has influence on the matter of textileThe qualification rate of amount and product. No matter but traditional stamp is plain net or cylinder, all exist technological process of production length, work by forceThe shortcomings such as degree is large, environmental pollution is serious. In recent years, along with correlation techniques such as computer, control, information and precision optical machinery manufacturesDevelopment, digital printing is more and more subject to people's attention, and has directly promoted the development of Green Textiles.

At present, the technical advantage that normally used digital printer is different from traditional printing machine does not still embody completelyCome, wherein maximum limited resource is, existing digital printer is improving after printing quality, due to high-quality stamp figureCase pixel is very large, and the transmission of whole pattern need spend a large amount of time, therefore than traditional printing machine, digital printerSpeed is lower, and this factor has limited using and promoting of digital printer greatly.

In addition the color that, digital printer is abundant, wide colour gamut and unique digital art style are not also excavated completely.

Summary of the invention

The present invention is in order to overcome the slow-footed problem of existing digital printer stamp, provide one have stamp speed fast andMass colour fast control method and control system for digital printer that printing quality is higher.

To achieve these goals, the invention provides a kind of digital printer mass colour fast control method, comprising:

The woven designs pattern of Real-time Collection after ink-jet apparatus ink-jet;

The woven designs pattern collecting is sampled, obtain sampled data;

Receive sampled data according to sampled data reconstruct woven designs pattern, by the woven designs pattern after reconstruct with pre-The floral designs template of depositing contrasts, and forms compare error;

According to compare error, adopt closed-loop automatic control method to regulate the mass colour of ink-jet apparatus ejection, reduce sprayCompare error between woven designs pattern after China ink and the floral designs template prestoring.

In one embodiment of the invention, adopt rapid sparse representation to sample to the woven designs pattern collecting.

In one embodiment of the invention, adopt rapid sparse representation to sample to the woven designs pattern collecting,Concrete step is:

Set up the Complete Orthogonal basic function of discrete cosine transform;

The woven designs pattern collecting is carried out to piecemeal, form the coordinate vector of woven designs pattern;

Each piece pattern is carried out to discrete cosine transform, obtain sampled data.

In one embodiment of the invention, the woven designs pattern after reconstruct and the floral designs template prestoring are contrastedStep comprise:

The locational space that woven designs pattern after reconstruct is made up of coordinate vector and the color being formed by color vectorSpatial Coupling forms pixel representation space;

On each pixel, contrast the color vector of the woven designs pattern after reconstruct and the floral designs template that prestoresColor vector in same position, forms value of statistical indicant according to predetermined threshold value;

Value of statistical indicant on each pixel is cumulative, form compare error.

In one embodiment of the invention, on each pixel, contrast the color vector of the woven designs pattern after reconstructWith the color vector of floral designs template in same position that prestore, form 0,1,2 according to predetermined threshold value, or four marks in 3In value one, wherein, 0 represent the floral designs that receive with the floral designs template prestoring at this locational R, G, BThe difference of three values is all less than threshold value, and 1 represents R, G, and in the difference of tri-values of B, any two are less than threshold value, and 2 represent R, G, B tri-In the difference of individual value, only have one and be less than threshold value, 3 represent R, G, and the difference of tri-values of B is all greater than threshold value.

In one embodiment of the invention, according to compare error, adopt closed-loop automatic control method to spray ink-jet apparatusMass colour regulate, reduce the woven designs pattern after ink-jet and the floral designs template that prestores between compare error thisBefore step, carry out color model conversion, form the discernible color model of ink-jet apparatus.

Another object of the present invention is, a kind of digital printer mass colour fast acting control system is also provided, and comprises and adoptingCollection unit, sampling unit, processing unit and control module. The fabric flower of collecting unit Real-time Collection after ink-jet apparatus ink-jetLine pattern. Sampling unit is sampled to the woven designs pattern collecting, and obtains sampled data. Processing unit receives hitsAccording to and according to sampled data reconstruct woven designs pattern, the woven designs pattern after reconstruct and the floral designs template that prestores are enteredRow contrast, forms compare error. Control module, according to compare error, adopts closed-loop automatic control method to spray ink-jet apparatusMass colour regulates, reduce the woven designs pattern after ink-jet and the floral designs template that prestores between compare error.

In one embodiment of the invention, sampling unit adopts rapid sparse representation to enter the woven designs pattern collectingRow sampling.

In one embodiment of the invention, sampling unit utilizes the Complete Orthogonal basic function of discrete cosine transform to represent fabricFloral designs, concrete step is:

Set up the Complete Orthogonal basic function of discrete cosine transform;

The woven designs pattern collecting is carried out to piecemeal, form the coordinate vector of woven designs pattern;

Each piece pattern is carried out to discrete cosine transform, obtain sampled data.

In one embodiment of the invention, processing unit is by the woven designs pattern after reconstruct and the floral designs template prestoringThe step contrasting comprises:

The locational space that woven designs pattern after reconstruct is made up of coordinate vector and the color being formed by color vectorSpatial Coupling forms pixel representation space;

On each pixel, contrast the color vector of the woven designs pattern after reconstruct and the floral designs template that prestoresColor vector in same position, forms value of statistical indicant according to predetermined threshold value;

Value of statistical indicant on each pixel is cumulative, form compare error.

In sum, mass colour fast control method and control system and prior art for digital printer provided by the inventionCompare, have the following advantages:

Collecting unit collects high-precision decalcomania, and sampling unit is sampled and obtained the floral designs that collectSampled data (as coefficient and corresponding coordinate vector) is also transferred to processing unit by sampled data. In this process, transmitBe the sampled data that data are less but not whole high-precision decalcomania has very high transmission speed. Processing unit onlyNeed to fewer coordinate vector just can obtain fast the woven designs pattern after reconstruct and the floral designs template that prestores betweenCompare error, thereby realize the quick control of mass colour. In contrast step, the woven designs pattern after reconstruct and the flower prestoringContrast between line pattern template adopts the mode of difference to form value of statistical indicant, and this way of contrast calculates very simple, fast,Thereby further improve the speed that produces compare error.

In addition, in the time that the textile design collecting is sampled, woven designs pattern is carried out to piecemeal after again to each piecePattern carries out respectively discrete cosine transform, and this can improve conversion rate greatly. Further, the automatic control of closed loop not only hasHigh degree of regulation, it has very high response speed simultaneously. For further improving governing speed, adopt Fuzzy Adaptive PIDControl algolithm is controlled ink-jet apparatus, and taking fuzzy control as coarse adjustment, PID controls as fine tuning, and both are in conjunction with reaching equallyTo the object that improves governing speed.

For above and other objects of the present invention, feature and advantage can be become apparent, preferred embodiment cited below particularly,And coordinate accompanying drawing, be described in detail below.

Brief description of the drawings

Figure 1 shows that the flow chart of the digital printer mass colour fast control method that one embodiment of the invention provides.

Figure 2 shows that in Fig. 1 the woven designs pattern collecting is sampled and obtained the particular flow sheet of sampled data.

Figure 3 shows that in Fig. 1 the woven designs pattern after reconstruct and the floral designs template prestoring are contrasted, formThe particular flow sheet of compare error.

Figure 4 shows that the structure chart of the digital printer mass colour fast acting control system that one embodiment of the invention provides.

Figure 5 shows that the structure chart of control module Fuzzy Adaptive PID Control algorithm in Fig. 4.

Detailed description of the invention

As shown in Figure 1, the digital printer that the present embodiment provides comprises with mass colour fast control method:

Step S1, the Real-time Collection woven designs pattern after ink-jet apparatus ink-jet. In this step, adopt area array camerasWoven designs pattern after Quick Acquisition ink-jet. Area array cameras is installed on PRINTED FABRIC top, profit while gathering woven designs patternUse two kinds of modes of row triggering that the frame of being exported by Hall element triggers and encoder is exported to combine, thereby forming surface battle array is adoptedCollection.

Concrete mounting means is: on first net head of the register control platform of printing machine, a hall sensing is installedDevice, the net head Hall element that often turns around just outwards sends a frame triggering signal. Encoder is arranged on fabric conveyer belt, andSynchronously send line triggering signal with the rotation of fabric conveyer belt. In the time that digital printer is started working, area array cameras is just synchronouslyFrame trigger and row triggering mode under the floral designs of Quick Acquisition fabric.

Step S2, the woven designs pattern collecting is sampled, obtain sampled data. In the present embodiment, adoptRapid sparse representation is sampled to the woven designs pattern collecting. Rapid sparse represents that algorithm is with less sparse unitA kind of algorithm of target acquisition important information. This algorithm only needs corresponding coefficient and corresponding coordinate thereof just can be expressedThe needed information of image, thus realize the compression of image. Adopt this kind of method to the woven designs pattern number collectingTo reduce volume of transmitted data, improve transmission speed according to compression.

In the present embodiment, in textile printing process, the floral designs of same batch of fabric are identical, therefore,Floral designs are sparse or compressible at certain transform domain, just can utilize with the noncoherent measurement matrix of transformation matrix rareDredge and be projected as low-dimensional observation vector. Preferably, using the Complete Orthogonal basic function of discrete cosine transform as transformation matrix unit. SoAnd the present invention is not limited in any way this. In other embodiment, can adopt discrete Haar transform or discrete Walsh transform etc.Other Complete Orthogonal basic function represents woven designs pattern as transformation matrix unit.

Concrete sampling step is:

Step S21, set up the Complete Orthogonal basic function of discrete cosine transform.

The Complete Orthogonal basic function of discrete cosine transform is:

$a_{\mathrm{ik}}=\sqrt{\frac{2}{N}}\cos \frac{(2k+1)\mathrm{i\π}}{N}$

Above-mentioned function has N sampled value, and what (i, k) represented is the coordinate figure of sampled point, i ∈ (0, N-1), k ∈ (0, N-1)。

Step S22, the woven designs pattern collecting is carried out to piecemeal, form the coordinate vector of woven designs pattern.

Because the floral designs data of whole fabric are larger, if directly carry out discrete cosine transform, need the regular hour.For improving the speed of discrete cosine transform, the present embodiment does not directly carry out discrete cosine change to the textile design decorative pattern collectingChange, but first the woven designs pattern collecting is carried out to piecemeal, be divided into nonoverlapping M*M fritter (M is greater than 2), then rightEach fritter carries out respectively discrete cosine transform. In the present embodiment, the woven designs pattern collecting is divided into 8*8 littlePiece. But the present invention is not limited in any way this.

Step S23, each piece pattern is carried out to discrete cosine transform, obtain sampled data. Described sampled data is pixelValue and corresponding coordinate vector. The matrix form of conversion is:

$\left[\begin{array}{c}{y}_0\\ y_1\\ .\\ .\\ .\\ y_{N-1}\end{array}\right]=\frac{2}{\sqrt{N}}\left[\begin{array}{cccc}\frac{1}{\sqrt{2}}& \frac{1}{\sqrt{2}}& ...& \frac{1}{\sqrt{2}}\\ \cos \frac{\mathrm{\π}}{2N}& \cos \frac{3\mathrm{\π}}{2N}& ...& \cos \frac{2N-1}{2N}\mathrm{\π}\\ .& .& .& .\\ .& .& .& .\\ .& .& .& .\\ \cos \frac{N-1}{2N}\mathrm{\π}& \cos \frac{3(N-1)}{2N}\mathrm{\π}& ...& \cos \frac{(2N-1)(N-1)}{2N}\mathrm{\π}\end{array}\right]\left[\begin{array}{c}{x}_0\\ x_1\\ .\\ .\\ .\\ x_{N-1}\end{array}\right]$

Wherein, x represents the pixel value that a certain coordinate vector before discrete cosine transform (in 0 to N-1) is located, and y representsThe pixel value that a certain coordinate vector after discrete cosine transform (in 0 to N-1) is located.

Step S3, receive sampled data according to sampled data reconstruct woven designs pattern, by the woven designs after reconstructPattern contrasts with the floral designs template prestoring, and forms compare error.

Prime minister, according to sampled data reconstruct woven designs pattern. In the present embodiment, adopting rapid sparse representation pairThe woven designs pattern collecting utilizes discrete cosine transform while sampling, adopt accordingly in the time of reconstruct woven designs patternInverse discrete cosine transform. But the present invention is not limited in any way this. When adopting discrete Haar transform or discrete Walsh transformWhen the woven designs pattern collecting sampling as transformation matrix unit Deng other Complete Orthogonal basic function, corresponding reconstructMethod is discrete Ha Er inverse transformation or discrete inverse Walsh transform.

The matrix form of inverse discrete cosine transform is:

$\left[\begin{array}{c}{x}_0\\ x_1\\ .\\ .\\ .\\ x_{N-1}\end{array}\right]=\frac{2}{\sqrt{N}}\left[\begin{array}{cccc}\frac{1}{\sqrt{2}}& \cos \frac{\mathrm{\π}}{2N}& ...& \cos \frac{N-1}{2N}\mathrm{\π}\\ \frac{1}{\sqrt{2}}& \cos \frac{3\mathrm{\π}}{2N}& ...& \cos \frac{3(N-1)}{2N}\mathrm{\π}\\ .& .& .& .\\ .& .& .& .\\ .& .& .& .\\ \frac{1}{\sqrt{2}}& \cos \frac{2N-1}{2N}\mathrm{\π}& ...& \cos \frac{(2N-1)(N-1)}{2N}\mathrm{\π}\end{array}\right]\left[\begin{array}{c}{y}_0\\ y_1\\ .\\ .\\ .\\ y_{N-1}\end{array}\right]$

Then, the woven designs pattern after reconstruct and the floral designs template prestoring are contrasted, form compare error.Concrete step is:

Step S31, the locational space that the woven designs pattern after reconstruct is made up of coordinate vector and by color vector groupThe color space becoming is combined to form pixel representation space. Because floral designs are by continuously arranged pixel in one group of two-dimensional spaceComposition,, in locational space, a pixel can be represented by a position coordinates vector (i, k). In color space, oneIndividual pixel can be represented by a color vector. Such as in rgb space, vector (R, G, B) can represent a pixel,R is red value, and G is green value, and B is blue valve. Now locational space and color space are merged into pixel representation space, so coloredLine pattern can be described completely by pixel representation space completely.

Step S32, the color vector that contrasts the woven designs pattern after reconstruct on each pixel and the decorative pattern that prestoresThe color vector of pattern template in same position, forms value of statistical indicant according to predetermined threshold value. In the present embodiment, value of statistical indicant is 0,1,2 or 3. Wherein, 0 represents that the floral designs that receive and the floral designs template prestoring are at this locational R, G, tri-of BThe difference of value is all less than threshold value, and 1 represents that wherein any two differences are less than threshold value, and 2 represent to only have a difference to be less than threshold value, 3Represent that three differences are all greater than threshold value.

Concrete comparison procedure is: when the woven designs pattern receiving and the floral designs template prestoring contrastTime, identical coordinate vector represents same pixel. The relatively color vector on this coordinate vector, then according to establishing in advanceThe threshold value of putting obtains value of statistical indicant 0,1, in 2 or 3 one.

Step S33, the value of statistical indicant on each pixel is cumulative, forms compare error.

Step S4, the woven designs pattern after reconstruct is carried out to color model conversion, form the discernible face of ink-jet apparatusColor model.

The color of the floral designs that ink-jet apparatus can be identified in existing digital printer and control appliance are (as industry controlMachine etc.) display pattern color adopt be different mechanism. Ink-jet apparatus adopts indigo-blue (C), pinkish red (M), Huang (Y) and black(K) combination of four kinds of pigment produces color (CMYK model), and display device on control appliance is by red (R), Huang(G), the combination results color (RGB model) of blue (B) three kinds of coloured light, therefore, need to be to the colouring information place of floral designsReason, color model conversion formula is:

R＝255×(100-C)×(100-K)/10000

G＝255×(100-M)×(100-K)/10000

B＝255×(100-Y)×(100-K)/10000

But the present invention is not limited in any way this. In other embodiment, when the ink-jet apparatus institute in digital printerThe color of floral designs that can identification and the mechanism that the color of the pattern of the demonstration on control appliance adopts are when identical, without enteringThis step of row, directly enters step S5 after step S3.

Step S5, according to compare error, adopt closed-loop automatic control method to regulate the mass colour of ink-jet apparatus ejection,Compare error between the floral designs template that reduces the woven designs pattern after ink-jet and prestore. In the present embodiment, adoptThe PID control method of fuzzy self-adaption regulates the mass colour of ink-jet apparatus ejection, makes the mass colour of ejection remain on regulationError range in.

The PID control method of fuzzy self-adaption comprises two parts, and a part is fuzzy self-adaption adjusting, and another part isPID regulates. Fuzzy self-adaption regulates and adopts triangle membership function, for the coarse adjustment of ink-jet apparatus; And PID control is used for sprayThe fine tuning of China ink equipment, thus realize controlling fast and accurately of mass colour. Its control procedure is:

First, set up membership function according to compare error and rate of change thereof by extreme value, and by compare error and rate of change thereofBe converted to membership values. Then, set up fuzzy rule and carry out fuzzy reasoning, common general fuzzy rule is as follows:

If (condition) Then (conclusion)

Such as setting up following fuzzy rule:

If (floral designs compare error is very large, and its error rate is very little) Then (get by ink-jet apparatus PID controllerLittle proportionality coefficient P, larger integral coefficient I and larger differential coefficient D). But the present invention is not to concrete fuzzy ruleBe limited in any way. In other embodiment, can corresponding fuzzy rule be set according to the situation of concrete compare error.

Finally, by reasoning information de-fuzzy, this process is contrary with fuzzification process, and it is that fuzzy variable is become to non-mouldStick with paste the process of variable, the actual PID that obtains being applied to ink-jet apparatus adjusts coefficient value, make the woven designs pattern that prints off withError between the floral designs that prestore maintains in setting range.

Digital printer provided by the invention mass colour fast control method, adopts rapid sparse representation to collectingWoven designs pattern is sampled, adopt less mutually incoherent sparse unit (in the present embodiment these sparse units be coordinate toAmount) represent woven designs pattern, not only realize the compression of image, improve the transmission of image; Meanwhile, adopt less sparseUnit represents woven designs pattern, in the time comparing, can obtain fast woven designs pattern and the floral designs that prestore betweenCompare error, thus realize the quick control of mass colour. In addition, the method for contrast is simple difference comparison, computational methods letterSingle, there is very high processing speed, this has also accelerated the control rate of mass colour greatly.

Corresponding with mass colour fast control method with above-mentioned digital printer, the present embodiment also provides a kind of numeral to printFlower machine mass colour fast acting control system, specifically comprises: collecting unit 1, sampling unit 2, processing unit 3 and control module 4. InIn the present embodiment, control module 4 comprises fuzzy self-adaption adjuster 41, PID controller 42 and ink-jet apparatus 43.

The woven designs pattern of collecting unit 1 Real-time Collection after ink-jet apparatus 43 ink-jets by the woven designs collectingPattern is transferred to sampling unit 2. In the present embodiment, sampling unit 2 integrates with collecting unit 1, sampling unit 2 and adoptingMore the needed time of short transmission also will be less for distance between collection unit 1. But the present invention is not limited in any way this. InIn other embodiment, sampling unit 2 and collecting unit 1 can be distinguished independent setting.

In the present embodiment, collecting unit 1 is area array cameras. Area array cameras is installed on PRINTED FABRIC top, gathers fabricWhen floral designs, utilize two kinds of modes of row triggering that the frame of being exported by Hall element triggers and encoder is exported to combine, therebyForming surface battle array gathers. Concrete mounting means is: on first net head of the register control platform 5 of printing machine, install one suddenlyYour sensor, the net head Hall element that often turns around just outwards sends a frame triggering signal. Encoder is arranged on fabric transmissionBring, and synchronously send line triggering signal with the rotation of fabric conveyer belt. In the time that digital printer is started working, area array cameras justThe floral designs of Quick Acquisition fabric under synchronous frame triggering and row triggering mode.

In the present embodiment, sampling unit 2 adopts rapid sparse representation to enter the woven designs pattern collectingRow sampling.

In the present embodiment, in textile printing process, the floral designs of same batch of fabric are identical, therefore,Floral designs are sparse or compressible at certain transform domain, just can utilize with the noncoherent measurement matrix of transformation matrix rareDredge and be projected as low-dimensional observation vector. Preferably, using the Complete Orthogonal basic function of discrete cosine transform as transformation matrix unit. SoAnd the present invention is not limited in any way this. In other embodiment, can adopt discrete Haar transform or discrete Walsh transform etc.Other Complete Orthogonal basic function represents woven designs pattern as transformation matrix unit.

Concrete sampling step is:

Step S21, set up the Complete Orthogonal basic function of discrete cosine transform.

The Complete Orthogonal basic function of discrete cosine transform is:

$a_{\mathrm{ik}}=\sqrt{\frac{2}{N}}\cos \frac{(2k+1)\mathrm{i\π}}{N}$

Above-mentioned function has N sampled value, and what (i, k) represented is the coordinate figure of sampled point, i ∈ (0, N-1), k ∈ (0, N-1)。

Step S22, the woven designs pattern collecting is carried out to piecemeal, form the coordinate vector of woven designs pattern.

Because the floral designs data of whole fabric are larger, if directly carry out discrete cosine transform, need the regular hour.For improving the speed of discrete cosine transform, the present embodiment does not directly carry out discrete cosine change to the textile design decorative pattern collectingChange, but first the woven designs pattern collecting is carried out to piecemeal, be divided into nonoverlapping M*M fritter (M is greater than 2), then rightEach fritter carries out respectively discrete cosine transform. In the present embodiment, the woven designs pattern collecting is divided into 8*8 littlePiece. But the present invention is not limited in any way this.

Step S23, each piece pattern is carried out to discrete cosine transform, obtain sampled data. Described sampled data is pixelValue and corresponding coordinate vector. The matrix form of conversion is:

$\left[\begin{array}{c}{y}_0\\ y_1\\ .\\ .\\ .\\ y_{N-1}\end{array}\right]=\frac{2}{\sqrt{N}}\left[\begin{array}{cccc}\frac{1}{\sqrt{2}}& \frac{1}{\sqrt{2}}& ...& \frac{1}{\sqrt{2}}\\ \cos \frac{\mathrm{\π}}{2N}& \cos \frac{3\mathrm{\π}}{2N}& ...& \cos \frac{2N-1}{2N}\mathrm{\π}\\ .& .& .& .\\ .& .& .& .\\ .& .& .& .\\ \cos \frac{N-1}{2N}\mathrm{\π}& \cos \frac{3(N-1)}{2N}\mathrm{\π}& ...& \cos \frac{(2N-1)(N-1)}{2N}\mathrm{\π}\end{array}\right]\left[\begin{array}{c}{x}_0\\ x_1\\ .\\ .\\ .\\ x_{N-1}\end{array}\right]$

Wherein, x represents the pixel value that a certain coordinate vector before discrete cosine transform (in 0 to N-1) is located, and y representsThe pixel value that a certain coordinate vector after discrete cosine transform (in 0 to N-1) is located.

Processing unit 3 receives the sampled data obtaining after sampling unit 2 samplings. First, according to these sampled data reconstructWoven designs pattern.

In the time adopting rapid sparse representation to sample to the woven designs pattern collecting, utilize discrete cosine transform,In the time of reconstruct woven designs pattern, adopt accordingly inverse discrete cosine transform. But the present invention is not limited in any way this. When adoptingWith other Complete Orthogonal basic functions such as discrete Haar transform or discrete Walsh transforms as transformation matrix unit to knitting of collectingWhen thing floral designs are sampled, corresponding reconstructing method is discrete Ha Er inverse transformation or discrete inverse Walsh transform.

The matrix form of inverse discrete cosine transform is:

$\left[\begin{array}{c}{x}_0\\ x_1\\ .\\ .\\ .\\ x_{N-1}\end{array}\right]=\frac{2}{\sqrt{N}}\left[\begin{array}{cccc}\frac{1}{\sqrt{2}}& \cos \frac{\mathrm{\π}}{2N}& ...& \cos \frac{N-1}{2N}\mathrm{\π}\\ \frac{1}{\sqrt{2}}& \cos \frac{3\mathrm{\π}}{2N}& ...& \cos \frac{3(N-1)}{2N}\mathrm{\π}\\ .& .& .& .\\ .& .& .& .\\ .& .& .& .\\ \frac{1}{\sqrt{2}}& \cos \frac{2N-1}{2N}\mathrm{\π}& ...& \cos \frac{(2N-1)(N-1)}{2N}\mathrm{\π}\end{array}\right]\left[\begin{array}{c}{y}_0\\ y_1\\ .\\ .\\ .\\ y_{N-1}\end{array}\right]$

Then, the woven designs pattern after reconstruct and the floral designs template prestoring are contrasted, form compare error.But the present invention is not limited in any way this. In other embodiment, reconstruct woven designs pattern and formation compare error can divideBe not arranged in different unit and carry out.

Concrete step is:

Step S31, the locational space that the woven designs pattern after reconstruct is made up of coordinate vector and by color vector groupThe color space becoming is combined to form pixel representation space. Because floral designs are by continuously arranged pixel in one group of two-dimensional spaceComposition,, in locational space, a pixel can be represented by a position coordinates vector (i, k). In color space, oneIndividual pixel can be represented by a color vector. Such as in rgb space, vector (R, G, B) can represent a pixel,R is red value, and G is green value, and B is blue valve. Now locational space and color space are merged into pixel representation space, so coloredLine pattern can be described completely by pixel representation space completely.

Step S32, the color vector that contrasts the woven designs pattern after reconstruct on each pixel and the decorative pattern that prestoresThe color vector of pattern template in same position, forms value of statistical indicant according to predetermined threshold value. In the present embodiment, value of statistical indicant is 0,1,2 or 3. Wherein, 0 represents that the floral designs that receive and the floral designs template prestoring are at this locational R, G, tri-of BThe difference of value is all less than threshold value, and 1 represents that wherein any two differences are less than threshold value, and 2 represent to only have a difference to be less than threshold value, 3Represent that three differences are all greater than threshold value.

Concrete comparison procedure is: when the woven designs pattern receiving and the floral designs template prestoring contrastTime, identical coordinate vector represents same pixel. The relatively color vector on this coordinate vector, then according to establishing in advanceThe threshold value of putting obtains value of statistical indicant 0,1, in 2 or 3 one.

Step S33, the value of statistical indicant on each pixel is cumulative, forms compare error.

Further, processing unit 3, except having above-mentioned comparing function, also can have again default new floral designs mouldPlate, suitably adjusts stamp speed, also can inquire about overall stamp disposition, and check the functions such as printing quality simultaneously.

In the present embodiment, due to the face of 43 floral designs that can identify of ink-jet apparatus in existing digital printerWhat the color of look and control appliance (as industrial computer etc.) display pattern adopted is different mechanism, and therefore, the present embodiment providesDigital printer also comprises color model converting unit (scheming not shown) with control module 4 in quick mass colour control system.

Color model converting unit is carried out color model conversion. Ink-jet apparatus 43 adopts indigo-blue (C), pinkish red (M), yellow (Y)Produce color (CMYK model) with the combination of black (K) four kinds of pigment, and display device on control appliance be by red (R),The combination results color (RGB model) of yellow (G), blue (B) three kinds of coloured light, therefore, need to carry out the colouring information of floral designsProcess, color model conversion formula is:

R＝255×(100-C)×(100-K)/10000

G＝255×(100-M)×(100-K)/10000

B＝255×(100-Y)×(100-K)/10000

But the present invention is not limited in any way this. In other embodiment, when the ink-jet apparatus 43 in digital printerThe color of floral designs that can identification and the mechanism that the color of the pattern of the demonstration on control appliance adopts when identical, are controlled singleUnit 4 is without comprising color model converting unit.

After color model conversion, the mass colour that control module 4 adopts closed-loop automatic control method to spray ink-jet apparatus 43Regulate, reduce the woven designs pattern after ink-jet and the floral designs template that prestores between compare error. In this enforcementIn example, the mass colour that adopts the PID control method of fuzzy self-adaption to spray ink-jet apparatus 43 regulates, and makes the mass colour of ejectionRemain in the error range of regulation, concrete Principles of Regulation block diagram as shown in Figure 5.

Control module 4 comprises two parts, and a part is fuzzy self-adaption adjuster 41, and another part is PID controller 42.Fuzzy self-adaption adjuster 41 adopts triangle membership function, for the coarse adjustment of ink-jet apparatus 43; And PID controller 42 is for rightThe fine tuning of ink-jet apparatus 43, thus realize controlling fast and accurately of mass colour. Its control procedure is:

First, set up membership function according to compare error and rate of change thereof by extreme value, and by compare error and rate of change thereofBe converted to membership values. Then, set up fuzzy rule and carry out fuzzy reasoning, common general fuzzy rule is as follows:

If (condition) Then (conclusion)

Such as setting up following fuzzy rule:

If (floral designs compare error is very large, and its error rate is very little) Then (get by ink-jet apparatus PID controllerLittle proportionality coefficient P, larger integral coefficient I and larger differential coefficient D). But the present invention is not to concrete fuzzy ruleBe limited in any way. In other embodiment, can corresponding fuzzy rule be set according to the situation of concrete compare error.

Finally, by reasoning information de-fuzzy, this process is contrary with fuzzification process, and it is that fuzzy variable is become to non-mouldStick with paste the process of variable, obtain being applied to the actual PID adjustment coefficient value of ink-jet apparatus 43, make the woven designs pattern printing offAnd the error between the floral designs that prestore maintains in setting range.

In sum, mass colour fast control method and control system and prior art for digital printer provided by the inventionCompare, have the following advantages:

Collecting unit 1 collects high-precision decalcomania, and sampling unit 2 is sampled to the floral designs that collectTo sampled data (as coefficient and corresponding coordinate vector) and sampled data is transferred to processing unit 3. In this processTransmission be the sampled data that data are less but not whole high-precision decalcomania has very high transmission speed. Process single3 floral designs templates that need fewer coordinate vector just can be obtained fast the woven designs pattern after reconstruct and be prestored of unitBetween compare error, thereby realize the quick control of mass colour. In contrast step, the woven designs pattern after reconstruct and prestoringFloral designs template between contrast adopt the mode of difference to form value of statistical indicant, this way of contrast calculates very simple,Fast, thus further improve the speed that produces compare error.

In addition, in the time that the textile design collecting is sampled, woven designs pattern is carried out to piecemeal after again to each piecePattern carries out respectively discrete cosine transform, and this can improve conversion rate greatly. Further, the automatic control of closed loop not only hasHigh degree of regulation, it has very high response speed simultaneously. For further improving governing speed, adopt Fuzzy Adaptive PIDControl algolithm is controlled ink-jet apparatus, and taking fuzzy control as coarse adjustment, PID controls as fine tuning, and both are in conjunction with reaching equallyTo the object that improves governing speed.

Although the present invention is disclosed as above by preferred embodiment, but not in order to limit the present invention, anyly know this skillSkill person, without departing from the spirit and scope of the present invention, can do a little change and retouching, and therefore protection scope of the present invention is worked asBe as the criterion depending on claims scope required for protection.

Claims (6)

1. a digital printer mass colour fast control method, is characterized in that, comprising:

The woven designs pattern of Real-time Collection after ink-jet apparatus ink-jet;

The woven designs pattern collecting is sampled, obtain sampled data, adopt rapid sparse representation to collectingWoven designs pattern is sampled;

Receive sampled data according to sampled data reconstruct woven designs pattern, by the woven designs pattern after reconstruct with prestoreFloral designs template contrasts, and forms compare error;

According to compare error, adopt closed-loop automatic control method to regulate the mass colour of ink-jet apparatus ejection, reduce after ink-jetWoven designs pattern and the floral designs template that prestores between compare error;

Adopt rapid sparse representation to sample to the woven designs pattern collecting, concrete step is:

Set up the Complete Orthogonal basic function of discrete cosine transform;

The woven designs pattern collecting is carried out to piecemeal, form the coordinate vector of woven designs pattern;

Each piece pattern is carried out to discrete cosine transform, obtain sampled data.

2. digital printer according to claim 1 mass colour fast control method, is characterized in that, by knitting after reconstructThing floral designs comprise with the step that the floral designs template prestoring contrasts:

The locational space that woven designs pattern after reconstruct is made up of coordinate vector and the color space being formed by color vectorBe combined to form pixel representation space;

On each pixel, contrast the color vector of the woven designs pattern after reconstruct and prestore floral designs template in phaseColor vector in co-located, forms value of statistical indicant according to predetermined threshold value;

Value of statistical indicant on each pixel is cumulative, form compare error.

3. digital printer according to claim 2 mass colour fast control method, is characterized in that, in each pixelOn some the color vector of the woven designs pattern of contrast after reconstruct and prestore the color of floral designs template in same position toAmount, forms 0,1,2 according to predetermined threshold value, or in four values of statistical indicant in 3, wherein, 0 represents the floral designs that receive andThe floral designs template prestoring is at this locational R, G, and the difference of tri-values of B is all less than threshold value, and 1 represents R, G, tri-values of BDifference in any two be less than threshold value, 2 represent R, G, only has one to be less than threshold value in the difference of tri-values of B, 3 represent R, G, BThe difference of three values is all greater than threshold value.

4. digital printer according to claim 1 mass colour fast control method, is characterized in that, is missing according to contrastPoor, adopt closed-loop automatic control method to regulate the mass colour of ink-jet apparatus ejection, reduce the woven designs pattern after ink-jetAnd before this step of compare error between the floral designs template prestoring, carry out color model conversion, form ink-jet apparatusDiscernible color model.

5. a digital printer mass colour fast acting control system, is characterized in that, comprising:

Collecting unit, the woven designs pattern of Real-time Collection after ink-jet apparatus ink-jet;

Sampling unit, samples to the woven designs pattern collecting, and obtains sampled data, and sampling unit adopts rapid sparseRepresentation is sampled to the woven designs pattern collecting;

Processing unit, receives sampled data according to sampled data reconstruct woven designs pattern, by the woven designs figure after reconstructCase contrasts with the floral designs template prestoring, and forms compare error;

Control module, according to compare error, adopts closed-loop automatic control method to regulate the mass colour of ink-jet apparatus ejection, subtractsCompare error between woven designs pattern after little ink-jet and the floral designs template prestoring;

Described sampling unit utilizes the Complete Orthogonal basic function of discrete cosine transform to represent the floral designs of fabric, concrete stepSuddenly be:

Set up the Complete Orthogonal basic function of discrete cosine transform;

The woven designs pattern collecting is carried out to piecemeal, form the coordinate vector of woven designs pattern;

Each piece pattern is carried out to discrete cosine transform, obtain sampled data.

6. digital printer according to claim 5 mass colour fast acting control system, is characterized in that, processing unit will weighWoven designs pattern after structure comprises with the step that the floral designs template prestoring contrasts:

The locational space that woven designs pattern after reconstruct is made up of coordinate vector and the color space being formed by color vectorBe combined to form pixel representation space;

On each pixel, contrast the color vector of the woven designs pattern after reconstruct and prestore floral designs template in phaseColor vector in co-located, forms value of statistical indicant according to predetermined threshold value;

Value of statistical indicant on each pixel is cumulative, form compare error.