JP2701194B2 - Iron print making equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an iron print. Iron print is a thermal transfer sheet that shows figures and original character designs.
It is transferred by pressing against the surface of a shirt or the like with an iron. Heat with an iron to transfer the figures on the sheet. Simply pressing and heating with an iron makes it easy to attach to the surface of the shirt. Numbers and names can be easily printed. At present, I request a specialty store to iron print because I need a sheet of letters and symbols.

However, since heat transfer can be performed with a household iron, if a sheet representing characters and the like can be easily obtained, printing can be easily performed at home. A thermal transfer sheet representing a figure or a character is used. In the case of a fixed character or symbol, a specialty store prepares a thermal transfer sheet of various sizes of the character and the symbol and can use the thermal transfer sheet. Since these are standard characters and symbols, they are sufficiently beautiful to be transferred as they are.

[0003]

2. Description of the Related Art Arbitrary figures and handwritten designs can be printed. In this method, when the original drawing is taken to a specialty store, the original drawing is read by an image scanner, a contour line is obtained, and a thermal transfer sheet is cut along the cutting line with a cutting plotter.

The term "heat transfer sheet" is used in a broad sense, and means that characters and the like on the sheet are transferred onto a shirt by applying heat and pressure. Actually, the base sheet and the transfer sheet are easily adhered to each other. The base sheet and the transfer sheet are thin plastic sheets. Only the transfer sheet is cut by the cutting plotter so that the left and right sides of the characters and figures are reversed. The base sheet does not cut. Only the transfer sheet is cut, but unnecessary portions of the transfer sheet are peeled off and removed. As a result, a thermal transfer sheet in which desired characters, figures, and the like are shown left and right is obtained.

[0005] The transfer sheet is placed on the shirt (the backing is on the upper side) and pressed with an iron from above.
The transfer sheet melts with heat and adheres to the shirting fabric. The base sheet does not melt and retains its original shape. Then, when the base sheet is peeled upward, the character and figure by the transfer sheet remain on the shirt. A small apparatus that can easily produce such a thermal transfer sheet is already on the market. This is an apparatus in which an image scanner and a cutting plotter are integrated, although the size of the original picture is limited to a small size. There is no correction function because the figure as it is read is cut out. There is already a technology that can easily print fixed characters, figures, numbers, handwritten characters and symbols on a T-shirt.

[0006]

However, the current iron print has the following disadvantages. The fixed-form letters and numbers are clearly transferred, because beautifully cut thermal transfer sheets are prepared in advance at specialty stores. Since this cannot be easily manufactured even in a specialty store, it must be stocked at all times so as not to run out of stock. Since the size and typeface of letters and numbers are various, various sizes and typefaces must be prepared to meet demand. This is a burden on specialty stores because of the large number of characters. Moreover, it is actually difficult to have many types of dimensional typefaces. Then, the range of choice becomes narrow.

On the other hand, printing original characters and symbols has a more serious disadvantage. Noise occurs when an original image is optically read by an image scanner. Because of the optical means, dirt on the paper surface appears, and the lines are jagged because they are read with dots, and diagonal lines and curves are not smooth. There are too many black parts and too many white parts. Since there is no correction function in a simple iron print maker currently on the market, there is such a drawback, and it is difficult to print neatly.

There is nothing that cannot be done if only the correction function is provided. The image read by the image scanner is projected on the screen of the display, and the image is corrected using a mouse. As in the case of normal image processing, curve approximation may be performed using a Bezier curve or the like. However, this correction is time-consuming because a person makes corrections while looking at the screen, and the operation must be mastered. Also, in the case of originals with free characters and symbols, if the person who wrote the originals and the person who corrects them are different,
It can hurt you. For this reason, at present, there is no simple iron print maker having a correction function. If the ironing machine had a correction function, it would have to be able to automatically and quickly correct it to take advantage of the original atmosphere.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an iron print maker which automatically corrects an original image, outputs the original image to a cutting plotter in a clean form, and enables a clean iron print with less noise. Also provided is an iron print maker which can store an original image with a small amount of data and output it at an arbitrary time. Further, there is provided an iron print maker which can be freely enlarged and reduced so that noise is not generated by the enlargement and reduction. Since fixed-form letters and symbols can be stored with a small amount of data and can be output instantaneously, there is no need to prepare a variety of multi-dimension ready-made transfer sheets, and a method of manufacturing iron prints that can reduce the burden on specialty stores. Provision is also an object of the present invention.

[0010]

SUMMARY OF THE INVENTION An iron print producing apparatus according to the present invention reads an original image such as a desired character figure with an image scanner, stores the image for each pixel, extracts a contour line, and extracts a contour line. , A line segment between adjacent joint points is approximated by an appropriate function, the contour line and the function are stored, and character / graphic data corresponding to the original drawing is generated from the stored information. The drawing is output to a cutting plotter, and a figure formed by correcting the original drawing is drawn on a transfer sheet. Extraction of junctions and function approximation are performed automatically.

In order to obtain the junction and approximate the function, reading errors and noises by the image scanner are removed.
The image is corrected neatly. Therefore, the character figure drawn on the transfer sheet can faithfully reproduce the characteristics of the original image. In the case of fixed-form characters and numbers, the character font serving as the original image is read by an image scanner and stored in a storage device in the form of data after contour line extraction, joint point extraction, and function approximation. This is prepared as common data from the beginning.

That is, the iron print making apparatus of the present invention optically reads desired characters and symbols, optically reads character / symbol data, and stores the characters / symbols corresponding to a finite number of pixels arranged vertically and horizontally. A symbol reading device, a contour point sequence extracting device for extracting a contour line of a character / symbol read in association with pixels arranged vertically and horizontally as a point sequence, and a two-dimensional coordinate (X, Y) of the extracted contour line. A contour point sequence storage device for storing t as an independent variable and X and Y as dependent variables for each continuous group, a curvature calculating mechanism for finding a curvature at each point of a point sequence for each group in x, y space, A perfect circle extraction mechanism that extracts a perfect circle from the data of each curvature, and a junction position extraction mechanism that extracts a point that cannot be spatially differentiated from the data of the curvature of the point sequence as a junction point; Approximate straight line and arc in order between adjacent joints in the group When a predetermined approximation accuracy is not obtained t
Is an independent variable, x and y are approximated by a piecewise polynomial with dependent variables, and the least squares approximation is repeated while increasing the number of dimensions of the piecewise polynomial until the approximation accuracy falls within a predetermined value, and a straight line Compressed data for storing a data approximation mechanism for approximating by arcs and piecewise polynomials, and a parameter of a function for approximating the coordinates of the above-mentioned junction points and adjacent junction points for each group of point sequences.
And a function parameter for inputting stored compressed data and approximating coordinates of joint points and adjacent joint points for each group of point sequences.
A contour reproduction mechanism that obtains data and reproduces the contour line in the opposite direction,
And a cutting mechanism for cutting the thermal transfer sheet along the outline of the reproduced character / symbol.

[0013]

FIG. 1 shows an outline of a method for producing an iron print. In, a manuscript is created using characters and symbols. This may be created on paper by any method such as handwriting or cad. When cad is used, the image reading operation can be omitted. This document is processed by the apparatus of the present invention. The thermal transfer sheet is cut along the original pattern by a cutting plotter as an output mechanism. Remove unnecessary parts from the mount.

The sheet cut by the cutting plotter is placed upside down on the fabric to be printed. Press the iron from behind. The heat causes the sheet to adhere to the fabric. Remove the backing paper. The apparatus according to the present invention can automatically perform reading up to the point where the original is read and the sheet is cut right and left by the cutting plotter.

FIG. 2 is a table showing the entire configuration. Here, all the mechanisms are described in advance. A. Image storage device B. Contour point sequence extraction device C. Outline point sequence storage device D. Data approximation mechanism AE Curvature calculation mechanism E '. Approximate curvature storage device F. Perfect circle extraction mechanism G. Perfect circular storage device H. Junction point position extraction mechanism I. Junction point position storage device Data approximation mechanism B.O. Compressed data output mechanism Compressed data storage device Contour reproduction mechanism Reproduction data output mechanism

The characters and symbols to be iron-printed vary depending on the person. The present invention applies to any characters
You can also use symbols. For example, the procedure will be briefly described for the symbol of the diode shown in FIG.

First, a figure of a diode written on paper is read by an image scanner (image reading device). This is the optical reading of characters and symbols. When a contour point sequence, which is a set of contour lines, is extracted, white characters and symbols are obtained. This is shown in FIG. Let the horizontal direction be the X axis and the vertical direction be the Y axis direction. Each point of the contour can be represented by two-dimensional coordinates. There are many continuous contour point sequences. These are treated independently.

Using the parameter display, the X and Y coordinates of the contour point are defined as functions of t. Since the contour point sequence is continuous, X
(T) and Y (t) are almost continuous functions with respect to t. Each contour point sequence group is approximated by a piecewise polynomial throughout. In the first approximation, one outline point sequence is approximated by one piecewise polynomial. This is to determine the curvature. The accuracy of the approximation may be low. Since a piecewise polynomial becomes a continuous function, the curvature is obtained by performing second order differentiation on each contour point sequence. A contour point sequence having a constant curvature is a perfect circle. This is separated as a perfect circle. The place where the curvature is large is the junction. In FIG. 3, crosses and curved points of the outline point sequence are marked with “x”. This is the junction.

The outline point sequence is divided by the joining points. Approximate a straight line, arc, or free curve between the joining points. The approximation is performed in the order of a straight line, an arc, and a free curve. First, approximate with a straight line. This can be expressed only by the starting point coordinates and the straight line. Next, it approximates with a circular arc. This can also be specified by the starting point, radius, and central angle. There is very little data to represent them. If it cannot be approximated by a straight line or a circular arc, a free curve is approximated. In this case, the space between the joining points is divided into M subsections and approximated by a piecewise polynomial. If the number of subdivisions is increased, the approximation can be increased, so that an approximation with desired accuracy can be made.

In this way, the parameters of the joining point and the straight line, the arc, and the free curve are obtained.
Stored as the data. According to the present invention, only a small memory capacity is required because the data is greatly compressed. The time required for reading is also short. Approximately 30 per character / symbol, depending on the number of strokes and complexity
Data of about 0 to 500 bytes is sufficient. If the image is still a black and white image, there is data for all pixels constituting the screen. For example, if there are 256 pixels in length and width, there are 8 kilobytes (kbytes), but the present invention can significantly compress data. Conversely, the data can be read out to reproduce straight lines, arcs, and free curves with reference to the junction. It can be reproduced to any size and any position by calculation. Reproduction data is output by a cutting plotter. The thermal transfer sheet is cut along the contour.

[0021]

【Example】

[A. Image storage device] This is a device in which characters and symbols written on paper or the like are read by optical means and stored as information decomposed for each pixel. A commercially available image scanner is used. The character / symbol portion is black, and the portion that does not constitute the character / symbol is white to form a binary image, which is stored for each pixel.

For example, 256 × using an image scanner
It is input with an accuracy of 256 dots. The number of dots is of course arbitrary, and the higher the number of dots, the higher the quality of what is stored as characters / symbols, but the larger the number of dots, the greater the computation time and storage capacity. May be used. For each dot (pixel), whether it is a white pixel or a black pixel is distinguished and temporarily stored. Hereinafter, one pixel may be referred to as a dot. A continuous black pixel row is referred to as a dot row. In order to indicate a point, a coordinate (x, y) including a horizontal number x and a vertical number y of a pixel on the screen is used. Coordinate variables are distinguished by adding various suffixes.

[B. Contour Point String Extraction Apparatus] The contour point string extraction apparatus performs an operation for obtaining a contour line of a read character or symbol. Since the coordinates of all black pixels are known,
An outline point sequence can be obtained as a boundary between a black pixel and a white pixel. Expression of a contour point sequence A contour point sequence is a sequence of black pixels on the outer periphery of a cluster of black pixels that are connected to the left, right, up, down, and diagonally. In the case of a closed curve element, there is a contour point sequence inside as well as outside. One closed point sequence is called a contour point sequence. Let U be the total number of contour point sequences. The U contour point sequences are numbered from 0 to U-1. Let the total number of contour points in the u-th contour point sequence be N (u)
Expressed by Number k is assigned to consecutive points in one contour point sequence.
Is attached. k is an integer of 0 to N (u) -1.

[0024] expressed by the u th k-th coordinate of the contour points of the contour point sequence _{^{(x k u, y k u}} ). All contour points _{^{{(x k u, y k}} u)} k = 0 N u -1 u = 0 U-1 (1)

Is represented by because _{k = 0} ^{N u -1} is that may take a value from the point sequence number k is 0 to N (u) -1. N (u) -1 contains parentheses and is 1
When it becomes a variable suffix because it cannot be a square, the parentheses are removed and written as Nu-1. Nu
-1 = N (u) -1. Since it is a suffix, it should be written on the top and bottom, but since this is not possible, it is divided into lower left and upper right. _{u = 0} ^U-1 means that the number u of the outline point sequence group is _{0 to} ^U -1
Is to take the value of The number u of the contour point sequence should be indicated by adding parentheses to the right shoulder of the variable.
Omit the brackets because they cannot be square. In fact, parentheses are attached as shown in the drawing. It is not a variable raised to the power of u.
This is common to the parameter t and the independent variables x and y.
u is a group number and is written as it is on the right shoulder of the variable, but it is actually in parentheses.

[C. Contour Point Sequence Storage Device] The contour point sequence storage device is a device for storing the contour point sequence obtained in the preceding stage. (X
_k ^u, and stores this in the form of ^{_{y k u) k = 0 N}} u -1 u = 0 U-1. As described above, U is the number of all point sequences, and u is the number assigned to the point sequence. The number of points in the point sequence u is N (u)
And k is the point number assigned to this. Such things expressed by ^{_{k = 0 N u -1 u =}} 0 U-1. (X _k ^u, y _k
^u ) is the x, y coordinates of the kth point in the uth point sequence.
Again, if N (u) -1 is the suffix,
u -1 is written.

[D. Data approximation mechanism A] There are two data approximation mechanisms. This is the first one, but is appended with A to distinguish it. This is necessary in order to obtain a point having a large curvature of the outline point sequence and obtain a joint point. The x and y coordinates of the contour line sequence for each continuous group are approximated by a quadratic piecewise polynomial where t is an independent variable and x and y are dependent variables, and the least squares method is used until the approximation accuracy falls within a predetermined range. The approximation is repeated to obtain an approximate polynomial for each group of contour point sequences. This is not to obtain the final data but to obtain the junction. The coordinates of each contour point sequence are read from the contour point sequence storage device.

This is decomposed into parameter display. That for each point, the two _{^{(x k u, y k u}} ) is the corresponding common parameter t on. This also with a subscript and t _k ^u. Although it is two-dimensional information, it uses parametric variables to make this a one-dimensional problem. u is the group number of the contour point sequence,
k is the number of a point in one outline point sequence.

[0029] By using the parametric, (t _k ^u,
x _k ^u) and (t _k ^u, a combination of the two coordinate y _k ^u) corresponding to each point of each contour point sequence. Hereinafter, the same operation is performed for two variables, and only one of them will be described. Contour point sequence in the group ^{_{u (t k u, x k}} u) approximates the t function S _x
(T) is given as a linear combination based on a second-order full-energy function system { _m }. S _x (t) approximates x as a function of t in group u. Similarly, S _y
(T) approximates y in group u. The evaluation as to whether it is appropriate as an approximation function is made by checking whether the error is within a predetermined range by the least square method.

It should be noted that S _x (t), S _y
By (t), the entire closed curve of the outline point sequence group u is approximated at once. Instead of having a junction in the middle, the whole is approximated by one function S _x (t). This is because the junction has not been determined yet. As described above, there is a simpler method for obtaining the curvature without such approximation. It is the data of the contour point sequence.
In this method, the discrete curvature is obtained by directly using the data. In order to carry out the present invention, such a discrete curvature may be used. However, it is not described here, and the approximation function S _x
The generation of (t) and S _y (t) will be described.

S _x (t) is an aperiodic m-th order full-energy
Expand using the function 展開_k as a basis. _{S x (t) = Σ k} = -m M + m C k x ψ k (t) (2)

The full-function function is a function name named by the present inventor. The degree m corresponds to the degree of the polynomial. M is the number of dimensions. In general, the m-th order full-energy function has a domain of [0, T], a parameter of k,
This parameter is represented with a suffix. C _k ^x
Is the coefficient of linear linear combination. ψ _k itself is a polynomial having a value near k.

Ψ_k (T) = 3 (T / M)^-mΣ_{q = 0} ^{m + 1}(-1)^q {T- (k + q) (T / M)} ^m ₊ / ｛Q! (M + 1-q)! ｝ (3)

Where k = −m, −m + 1,..., 0, 1, 2,.
+ M

The plus added below the m-th power is 0 when the value in the parenthesis is negative and m-th when the value is positive, and is defined as follows.

(T−a) ^m ₊ = (t−a) ^m t> a, (4) 0 t ≦ a (5)

The basis function ψ _k is a chevron-shaped function having a finite value from section numbers _{k to k} + m + 1 and having 0 on both sides. This is 0 such as {t- (k + q) (T / M)} ^m ₊
The coordinates of the m-th order function that rises from are shifted one by one (q is increased one by one) and are superimposed. 0 when t> (k + m + 1) (T / M)
Must. Under this condition, the superimposition coefficient is (−1) ^q / ｛q! (M + 1-q)! It is determined as｝. The size T of the area is the number N of points in the outline point sequence group.
Although it is easy to make it equal to (u), it may be defined as being proportional. As described above, the contour point sequence is approximated by using the full-energy function. However, since there are many division points having a T / M interval, the contour point sequence can be approximated without a joint point. To increase the degree of approximation, the order m of the full-energy function may be increased.

The inventor's argument is that many functions representing the variation of physical quantities in the natural world are expressed as linear combinations of first-order and second-order full-energy functions. The full-ency function is not a complete orthogonal normalization function. If a function up to ∞ is adopted as m and this is a linear combination, any function can be expressed. This is no doubt. However, the present inventor does not say so, but it is possible to write down the variation of the physical quantity in the natural world with a full-energy function having a small number of dimensions. Here, only m = 2 is adopted.
As a result, contour lines such as characters and symbols can be expressed without excess and deficiency.

If the most appropriate function system is adopted and the variation of the physical quantity is written by the linear combination, an optimal approximation can be obtained with the fewest functions. If the function system is not good, you have to expand the expression of linear combinations based on many functions. In this case, a good approximation cannot be obtained, and the number of final data increases, resulting in a heavy load on the storage device. Also, it is not easy to read and use this. You should choose the optimal function system. The present inventor thinks that m = 2 is optimal.

The inventor uses a full-energy function of m = 2 here. This is a quadratic curve over three sections. The rise and fall at both ends is a quadratic function. It is the maximum at the center point, but also a quadratic function in the vicinity.

In general, the m-th order full-energy function is (m +
1) A smooth (m ≧ 2) function that exists over the interval and has a maximum at the center. Both ends rise and fall to the m-th power. The function form at the center is also the m-th power. Baseψ
_When the parameter _k of k increases by one, it means that the original one has been translated to the right by one.

In the above equation, when m = 2,

[0043] _{S x (t) = Σ k} = -2 M + 2 C k x ψ k (t) (6)

Ψ _k (t) = 3 (T / M) ⁻² Σ _{q = 0} ³ (−1) ^q ｛t− (k + q) (T / M)｝ ² ₊ / ｛q! (3-q)! ｝ (7)

Is as follows. The basis function is Δt− (k + q) (T
/ M)} is a superposition of the quadratic function rising from four 0-shifted laterally by T / M is the ^two _+. The number of subdivisions is a function with values from k to k + 3. k + 4
As described above, since the constant is 0, the superimposition coefficient becomes (−
1) ^q / ｛q! (3-q)! It becomes｝. The number of basis functions is M + 5. M is the number of divisions of all sections, and this is called an approximate dimension number. This should not be confused with the order m of the full-energy function.

As the number of dimensions M is increased, any complicated change can be approximated as such. If the number of dimensions M is large, the calculation takes time and the amount of data to be stored increases. It is desirable to perform the approximation with the minimum number of dimensions that can obtain the necessary approximation. The degree of approximation can be judged by this how the original contour point sequence _{^{(x k u, y k u}} ) that is closer to.
This is evaluated by the least squares method, which is

[0047] _{Q = Σ {S x (t} k u) -x k u} 2 + {S y (t k u) -y k u} 2 (8)

Is to be minimized. The range of integration is all points of the outline point sequence group u. Here, since the curvature is merely obtained, the accuracy need not be so high. The coefficient _Ch is determined, and the number of dimensions is M. When defining a certain M, equation (6), is uniquely determined coefficient C _h ^x (7). However, this coefficient does not always satisfy the restriction by the least squares method. In this case, the number of dimensions M is increased by one. And this in determining the coefficient C _h of the dimension number M reaches to the desired approximation range.

[E. Curvature operation mechanism] Since the approximate function has been obtained for all the contour point sequence groups, this is second-order differentiated to obtain the curvature at each contour point sequence group and each point. K-th point of the contour point sequence group ^{_{u (x k u, y k}} u) curvature at K (t _k ^u
)

K (t_k ^u ) = ｛S_x '(T_k ^u ) S_y '' (T_k ^u ) -S_x '' (T_k ^u ) S _y '(T_k ^u )｝ / ｛S_x '(T_k ^u )^Two + S_y '(T_k ^u )^Two ｝^3/2 (9)

Can be calculated by First u =
This calculation is started from the point k = 0 in the group of contour points 0. This calculation is performed for each point. That is, if the calculation can be performed for the k-th point, then the same calculation is performed for the (k + 1) -th point. When the calculation is completed for one outline point sequence group, the process moves to the next outline point sequence. Then, the curvatures are obtained for all the points in all the outline point sequences.

[E '. Approximate curvature memory] curvature K obtained in the previous stage of (t _k ^u) point (edge point sequence group u, the point number k) is a device for storing for each.

[F. Perfect circle extraction mechanism] This is to determine whether a certain contour point sequence is a perfect circle or not based on the approximate curvature and extract a perfect circle. A perfect circle means that the curvatures at each point in the outline point sequence are all equal.
Actually, since there is noise, the extraction is performed under the condition that the curvature is within a certain small error range from a certain value. There are quite a few circles in letters and symbols. However, since the perfect circle mentioned here is about a contour line, it refers to an isolated perfect circle. If the part of the perfect circle is in cross contact with another straight line or curve, it is not extracted as a perfect circle.

Extracting a perfect circle has the following advantages. In the first case, even if a circle that is originally a circle is slightly distorted due to noise, the data is converted into a true circle, so that the noise drops and the shape can be determined more accurately. Since a circle can be specified only by the coordinates of the radius and the center, it is extremely effective in data compression.

[G. Perfect circle storage device] Stores the center coordinates and radius r of the perfect circle obtained in the previous stage. Thus, the data of the group u can be described by three values. Since the target is characters and symbols, all contour point sequences are closed curves. In the case of a single perfect circle, this is an isolated circle point because the entire inside is a circle filled with black pixels. In the case of a double perfect circle, the space between the double circles corresponds to a circle filled with black pixels.

[H. Joining Point Position Extraction Mechanism] The joining points include a joint between a straight line and a straight line, a joint between a curve and a curve, a joint between a straight line and a curve, and the like. Since the lines with different gradients come into contact, this is called a junction. Junction points play a very important role when approximating functions of characters and symbols. Here is the gist of the present invention. The present invention can minimize the amount of data while maintaining high quality of characters and symbols through accurate and appropriate determination of the junction. The joining point is obtained from the curvature given by the approximate expression of the previous piecewise polynomial. This is determined as a point having a large curvature. Join points are obtained for all contour point sequences.

In the schematic diagram of the diode in FIG. 3, the junctions are indicated by crosses. There are a total of three contour lines, including an outer circular contour line Y, an inner contour line, and a contour line. Although there are eight junctions of the outer contour line Y, only the upper half is marked. Tsu-ne is a short line segment, ne-na is a semicircular arc, na-ra is a short line segment,
The toes are short arcs or free curves. Inner contour line,
Since Seo is symmetric, I will explain about Re. M to U are line segments, U to ヰ are line segments, and ヰ to No are line segments, but they are curved near No and are free curves. No ~ o is a line segment, oh ~
Ku is also a line segment, Ku-ya is a line segment, Yama is a line segment, and Ma is a semicircular arc. This also has many straight lines. Then there are many arcs. Geometrically, both ends of a line segment are determined, and a straight line is a figure without both ends. In this specification, a line segment and a half line are also called straight lines.

[I. Joint position storage device] This is the joint number and coordinates ｛d _i (x _i ^u , y _i) determined by the above operation.
^u )｝ is stored.

[N. [Data approximation mechanism B] Then, when the joining point is determined, the outline point sequence is divided into several sections by the joining point. The section divided by the junction is approximated by a piecewise polynomial. The approximation of this piecewise polynomial is the same as that described above for the data approximation mechanism A, but in the previous one the approximation interval spanned the entire contour point sequence group. This time, instead, a piecewise polynomial approximation is performed for each junction.

The data approximation mechanism B is a mechanism for approximating data from data such as a contour point sequence, a final joint point, and a perfect circle obtained so far. It is a central part of the present invention. Which is input from the respective storage device contour point string storage device ...... contour point sequence ^{_{{(x k u, y k}} u)}
^{_{k = 0 N u -1 = 0}} U-1 junction position storage ...... junction ^{_{{(x i u, y i}} u)
_{i = 0} ^I-1 perfect circle storage device ... circle Circle (u)

Is as follows. A straight line, an arc, and a free curve are approximated between two adjacent joining points (between the joining points). As in the previous approximation, the x component is converted to s _x (t) using the parameter t.
, The y component is represented by s _y (t).

First, the entire contour point sequence is defined as a parameter t.
This is the same method as expressed in. But this time, since the region is between the junctions, the range of t and t and s _x
The correspondence between (t) and s _x (t) is different from the previous one. Whether the section starting from a certain junction is a section of a straight line, a section of an arc, or a section of a free curve is known when the curvature is obtained at each point.

Since the properties of the sections can be distinguished in this way, it is easy to determine the parameters for the approximate calculation. [Approximation of Straight Line Section] Approximation of a section starting from a junction of straight lines will be described. It is determined to be a straight line in the extraction stage of the joint point.

The proportional constant between the parameter t and s _x (t), s _y (t) is a parameter. However, this proportionality constant does not need to be stored. Start point (x ₁ , y ₁ ) if it is a straight section
If the end point ( _xn3 , _yn3 ) is known, a straight line may be drawn between them. The end point (x _n3 , y _n3 ) is given as the start point of the next section, and need not be stored here. It is only necessary to set a flag that is a straight line with the start point coordinates.

[Approximation of Arc Section] The approximation of the section starting from the junction of the arcs will be described. This section is determined to be a circular arc at the point of joint point extraction. The approximate curves s _x (t) and s _y (t) representing the arc are expressed by the following linear combination of trigonometric functions. If the observation interval is t 区間 [0, T],
s _x (t) and s _y (t) are

S_x (T) = A_xcos (2πt / (T / n_arc )) + B_x sin (2πT / (T / n _arc )) + C_x (10)

S_y (T) = A_ycos (2πt / (T / n_arc )) + B_y sin (2πT / (T / n _arc )) + C_y (11)

Is represented by n _arc is the ratio of the arc to the total circle. That is, it is a value obtained by dividing the central angle of the arc by 360 degrees. For example, in the case of a _quadrant , n _arc is 1/4
It is. Therefore, 2πn _arc is the central angle of this arc. The variable 2πt / (T / n _arc ) is the central angle from the starting point of the arc to the point corresponding to the parameter t. (C _x , C
_y ) is the coordinates of the center of the arc. At this time,

A _x ² + B _x ² = A _y ² + B _y ² (12)

[0070] _{B y / A y = B x} / A x (13)

If the above holds, the approximation function becomes an arc. In this case, parameter defines an arc - data each coefficient A _x of the function, B _x, is _{C x, A y, B y} , C y, n arc. If it is known from the beginning that this section is a circular arc, such parameters can be uniquely determined from the coordinates of the start and end points, the curvature and the coordinates of one point in the middle.

[Approximation of Free Curve] Even at the junction of straight lines,
A section starting from a junction that is not a junction of arcs is approximated by a free curve. Although represented by the parameter t, the outline point sequence is (x _i3
^u , y _i3 ^u ), and corresponding to t,
(T _i3 ^u , x _i3 ^u ) and (t _i3 ^u , y _i3 ^u ) are used as parameters. Until now, the suffix of the contour point sequence was k. However, since k is used as the section number of the section, i3 is used as the contour point sequence number instead of k. Then, the total number of contour point sequences is set to n3.

Then, s _x (t) and s _y (t) are developed using the second-order full-energy function ψ _k3 as a base. This is 3
A function that has a value in only one subdivision. The interval is [0,
T], the quadratic full-energy function ψ _k3 is an M-dimensional functional system

Ψ _k3 (t) = 3 (T / M) ^-2 Σ _{q = 0} ³ (−1) ^q (t−ξ _{k + q} ) ² ₊ / {(q! (3-q)!)} (14) k = −2, −1, 0, 1, 2,... M + 2

Is as follows. Using this as the base, s _x (t _i3 ), s
_y (t _i3 ) is calculated using the coefficients c _k ^x and c _k ^y .

S _x (t _i3 ) = Σ _{k = −2} ^{M + 2} c _k ^x ψ _k3 (t _i3 ) (15) _sy (t _i3 ) = Σ _{k = −2} ^{M + 2} c _k ^y ψ _k3 (T _i3 ) (16) here,

When t> ξ _{k + q} (t−ξ _{k + q} ) ² ₊ = (t−ξ _{k + q} ) ² (17) When t ≦ ξ _{k + q} (t−ξ _{k + q} ) ² ₊ = 0 (18) ξ _{k + q} is a subdivision when the section T is divided into M equal parts.

Ξ _{k + q} = (k + q) T / M (19)

The coefficients c _k ^x and c _k ^y are defined as the values (x _i3
^u , y _i3 ^u ) and the values of s _x (t _i3 ) and s _y (t _i3 ) are determined to be similar. Determine the value of the coefficient by the least squares method. The square error Q is

Q = Σ _{i3 = 1} ⁿ³ | x _i3 ^u −s _x (t _i3 ) | ² −Σ _{i3 = 1} ⁿ³ | y _i3 ^u −s _y (t _i3 ) | ² (20)

Is defined by (15), (16)
By solving in reverse, the coefficients can be determined. A square error is obtained by inserting this coefficient. If this does not fall below a predetermined threshold, the number of dimensions is increased. The same is repeated so that the square error is equal to or less than a predetermined threshold. Thereby, the number of dimensions and the coefficient are determined.

[O. Compressed Data Output Mechanism] The outlines of characters and symbols have been separated into straight lines (line segments), true circles, arcs, and free curves by the above procedure. These have a starting point and an ending point, and have parameters such as inclination, center, and radius. The data to be stored differs depending on the type.

In the case of straight line data, a flag indicating a straight line and the starting point coordinates of the straight line are stored as data. Since the end point coordinates are given as the start point of the next section, there is no need to store them here.

In the case of the perfect circle data, the data can be obtained directly from the perfect circle storage device G. This has already been selected by the first data approximation mechanism A. In the case of a perfect circle, the flag indicating the perfect circle, the center coordinates of the circle, and the radius of the circle are provided.
Stored as data.

As the arc data, a flag indicating an arc, the coordinates of the starting point of the arc, the arc division length (arc length / perimeter),
Stores the number of contour points and function coefficients. De of free curve - The data, dimensionality of the function, the contour points, the middle point (μ _x, μ _y) of the variation of the contour point sequence and the coefficient of the function c ^x, stores c ^y.

[P. Compressed data storage device] Stores data such as straight lines, perfect circles, circular arcs, and free curves output from the compressed data output mechanism. This is output at an appropriate time after being stored. Up to this point, the data is compressed and generated and stored. An apparatus for reproducing characters and symbols from accumulated data will be described below. Table 1 shows the data structure stored in the compressed data storage device P.

[0087]

[Table 1]

The size of the data will be described. If a straight line exists between the joining points, one byte is used for the flag indicating the straight line, and two bytes are used for indicating the start point of the line segment (x coordinate and y coordinate).
Requires a total of 3 bytes. When the arc between the joining points is an arc, the flag indicating the arc is 1 byte, and the start point of the arc is 2 bytes.
4 bytes to represent the arc center angle, 1 byte to represent the number of contour points, 1 to represent the approximate function coefficients (there are 6)
A total of 20 bytes are required for 2 bytes. In the case of a free curve between the joining points, 1 byte is used to represent the dimension number M of the function, 1 byte is used as the number of contour points, 2 bytes is used to represent the center of variation of the contour points, and 2M is used to represent the coefficient of the approximate function. Bytes, 4 in total
+2 Mbytes.

The outline reproduction mechanism R and reproduction data described below
The data output mechanism T is a mechanism for reproducing characters / symbols to an arbitrary size and outputting them to a cutting plotter.

[R. Contour Reproducing Mechanism] This is a mechanism for reproducing a contour to be a skeleton of a character or a symbol from stored compressed data. The contour may be a straight line, a perfect circle, an arc, or a free curve.

[Reproduction of Straight Line] Reproduction of a straight line is performed by connecting a straight line from the coordinates of the starting point to the coordinates of the joining point in the next section. No data regarding the inclination of the straight line is required. [Reproduction of Perfect Circle] Reproduction of a perfect circle is performed by drawing a circle having a given radius around the center coordinates from data of the coordinates and the radius of the center. [Reproduction of circular arc] Reproduction of circular arc is performed by storing the stored data (A _x , B _x ,...).
・) Is substituted into the following equation.

S _x (t) = A _x cos ｛2πt / (T / n _arc )｝ + B _x sin ｛2πt / (T / n _arc )｝ + C _x (21) S _y (t) = A _y cos {2πt / (T / n _arc )} + B _y sin {2πt / (T / n _arc )} + C _y (22)

The x and y coordinates are obtained from S _x (t) and S _y (t) by changing the parameter t in the interval [0 to T].

[Reproduction of Free Curve] The value of the basis ψ _K3 of the approximation function at each sample point t _i is such that the sample point t _i has an interval [(L
-1) (T / M), L (T / M)] (1 ≦ L
≦ M), with _{p = L-t i × M} / T,

Ψ _k3 (t _i ) = 0.5 p ² k = L (23) ψ _k3 (t _i ) = p (1−p) +0.5 k = L + 1 (24) ψ _k3 (t _i ) = 1 −ψ _L3 (t _i ) −ψ _{L + 13} (t _i ) k = L + 2 (25) ψ _k3 (t _i ) = 0 k ≦ L−1, L + 3 ≦ k (26) Here, L is a natural number of dimensions M or less. Since the numbers have the same property, M's should be written. However, since 'does not become a 1/4 angle, it is represented by L.

Using such a basis ψ _K3 , the approximate function value S (t _i ) at each sample point is S (t _i ) = Σ _{k = L} ^{L + 2} C _k ψ _k3 (t _i ) (27) ).

[T. Reproduction Data Output Mechanism] This is a cutting plotter for cutting a thermal transfer sheet.
Since the contour is obtained, the sheet is cut by moving the blade of the cutting plotter in accordance with the contour. For example, a cutting plotter of ROMM's CAMM-1 series can be used.

FIG. 4 is a view showing the actual mechanism of the present invention. It consists of an image scanner, a personal computer and a cutting plotter. The above mechanism is housed in a custom IC fixed to a printed circuit board. It is not simply installed on a personal computer as software. In the present invention, the original image is stored in the form of the coordinates of the joining points and the coefficients, so that the original image can be enlarged or reduced to any magnification. Also, the center can be arbitrarily specified for the coordinates. For this reason, an arbitrary design character / symbol can be output in an arbitrary size. That is, a sheet of a desired size can be cut out without being limited by the size of the original image.

[0099]

According to the present invention, characters / symbols, which are original images such as handwriting, are optically read, stored as small data, and output to a cutting plotter. You can easily and quickly create the desired iron print. There is no need to prepare many original drawings of various designs. This is a very useful invention.

[Brief description of the drawings]

FIG. 1 is a schematic diagram illustrating an iron printing method.

FIG. 2 is a configuration diagram showing the entire mechanism of the present invention.

FIG. 3 is a view for explaining extraction of a contour point sequence and extraction of a joint point using a figure of a diode as an example.

FIG. 4 is a perspective view showing the actual structure of the device of the present invention.

Continuation of the front page (56) References JP-A-60-49483 (JP, A) JP-A-57-159363 (JP, A) JP-A-2-278377 (JP, A) JP-A-6-83952 (JP) JP-A-6-96199 (JP, A) JP-A-6-348837 (JP, A) JP-A-2-60324 (JP, A) "Automatic compression of high-quality character fonts", IEICE D. , VOL. J70-D, NO. 6 (June 1987) p. 1764-1172 "Handwritten Kanji / Hiragana Recognition Using Relaxation Matching Method by Curve Segment Approximation", IEICE D-II, VOL. J73-D-II, NO. 9 (September 1990) 1448-1457 "Multi-stage extraction method of joint points in automatic multi-font function", IEICE C, VOL. 113-C, NO. 12 (December 1993) 1136-1143, "Splice-in function and its application", Kyoiku Shuppan (1979), "A method of automatic compressing fonts with high resolution", Proc. of 1st Int. Conf. Document Analysis and Recognition, (I CDAR91), vol. 1, pp. 251-259 (1991) "Compressing Data Volume of F Left Venticular Cineangiograms", IEEE Tr.

Claims (1)

(57) [Claims] 1. An apparatus for cutting a thermal transfer sheet along a desired character or symbol to create an iron print,
A character / symbol reading device that optically reads desired characters and symbols and stores them in correspondence with a finite number of pixels arranged vertically and horizontally, and a dot sequence of outlines of characters and symbols read in association with pixels arranged vertically and horizontally. A contour point sequence extraction device for extracting as
A contour point sequence storage device that stores the two-dimensional coordinates (X, Y) of the extracted contour line for each continuous group, and that the X and Y coordinates of the contour line sequence for each group are t, an independent variable, x Is approximated by a quadratic piecewise polynomial with y and y as dependent variables, and the least-squares approximation is repeated while increasing the number of dimensions of the piecewise polynomial until the approximation accuracy falls within a predetermined range. A data approximation mechanism A to be obtained, a curvature calculation mechanism to obtain a curvature at each point of a point sequence for each group in the x and y spaces from the above-described approximation, and a perfect circle extraction for extracting a perfect circle from the curvature data for each group A mechanism, a joint position extraction mechanism for extracting a point having a curvature larger than a certain value from the curvature data of the point sequence as a joint, and a straight line and an arc in order between adjacent joint points in the same point sequence group. And when the predetermined approximation accuracy cannot be obtained with this, t
Is approximated by a quadratic piecewise polynomial with x and y as dependent variables, and least squares approximation is repeated while increasing the number of dimensions of the quadratic piecewise polynomial until the approximation accuracy falls within a predetermined value. A data approximation mechanism B for approximating a point between points by a straight line, an arc, or a piecewise polynomial, and the coordinates of the above-mentioned joint points and a parameter of a function for approximating between adjacent joint points are stored for each of a group of perfect circle data and a sequence of points. A compressed data storage mechanism, a contour reproducing mechanism for inputting the stored compressed data, obtaining a function parameter approximating the coordinates of the perfect circular data and the joining points for each group of the point sequence and an adjacent joining point, and reproducing the contour line; A cutting mechanism for cutting the thermal transfer sheet along the contours of the reproduced characters / symbols.