JPS6255156B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a modified character signal generation circuit, and particularly to a modified character signal generation circuit suitable for outputting modified characters to a CRT (cathode ray tube) such as a display device or a recording device. Related.

Recently, computer typesetting using CRTs has been implemented with the aim of speeding up and automating phototypesetting. To create modified characters in this computer typesetting,
The deflection position of the CRT beam is determined by the coordinates x, y of each bright spot of the true character in the virtual coordinate system whose base point is the center of the character.
For example, the coordinates are changed to linearly transformed coordinates X and Y. The circuit that generates the signal that controls the deflection of the CRT beam at this time is sometimes called a modified character signal generation circuit.

By the way, in the conventional deformed character signal generation circuit, the CRT beam is deflected to the new coordinates X, Y by performing calculations or conversions as shown in the following equation for the coordinates x, y of each bright spot of the original character. Ta.

X=1/2{k ₁ (x+y)+k ₂ (x-y)} Y=1/2{k ₁ (x+y)-k ₂ (x-y} In other words, using the conventional modified character signal generation circuit, In addition, if the coefficients k ₁ and k ₂ are instructed to be 1, it is theoretically possible to output the original character without any deformation to the CRT.

However, such calculations are often performed in an analog manner, and as a result, the accuracy is poor, and even if the coefficients k ₁ and k ₂ are instructed to be 1, conventional circuits output characters that are slightly deformed from the original characters. There were flaws.

It is also possible to perform all of the above calculations digitally, in which case the accuracy problem is avoided, but
The disadvantage was that the circuit configuration was complicated and expensive.

Thus, the present invention is aimed at eliminating the above-mentioned drawbacks, and is based on the following: X=Ax+BPy, Y=AQx+By(A, B,
This purpose is achieved by a deformed character signal generation circuit composed of a combination of digital and analog arithmetic circuits that performs calculations based on a conversion formula (P, Q are deformation rates), and an embodiment thereof will be described in detail below according to the drawings. Explain.

FIG. 1 is a block diagram of a display section in phototypesetting to which the present invention is applied. In the figure, MEMO is a pattern memory; CNL is a control device; DEF1 is a main deflection circuit; DEF2 is a sub-deflection circuit; LGT is a brightness control circuit; AD is an analog addition circuit; CRT is a cathode ray tube.

In this display section, as shown in the figure, first, a deflection control signal (main deflection control signal, deformation control signal) and a character pattern from the pattern memory MEMO are input to the control device CNL. The control device CNL controls the main deflection circuit DEF1 to specify the position of the character to be displayed on the CRT, and controls the sub-deflection circuit DEF2 to specify the position of the character to be displayed on the CRT. The sub-deflection circuit DEF2 specifies the position according to the displacement, and controls the brightness control circuit LGT to adjust the brightness. Main deflection circuit DEF
1 and the outputs of the sub-deflection circuit DEF2 are combined by an analog adder circuit AD and sent to the deflection coil of the CRT. As a result, characters are displayed at the specified position on the CRT.

When the present invention has the above configuration, the sub-deflection circuit
It is used as DEF2 and will be explained in detail in FIG.

FIG. 2 is a block diagram of a modified character signal generation circuit according to the present invention, which is used as the sub-deflection circuit DEF2, where white arrows indicate digital signals composed of, for example, binary codes, and black arrows indicate analog signals. It shows. In the figure, 11, 21 are digital-to-analog conversion circuits (hereinafter referred to as DA) that convert digital input signals to analog signals; 12, 13,
22 and 23 are multiplying type digital-to-analog conversion circuits (hereinafter referred to as multiplication type) that input the analog output and digital signal of the previous stage and generate an output signal of an analog quantity equal to the product of each analog quantity and digital value.
(referred to as DA); 14 and 24 are the two multiplication types in the previous stage
This is an addition circuit that generates an analog output signal by adding the analog outputs of the DA.

To explain the operation, first, command signals Sx and Sy containing the deformation rates A and B in digital values are input to the DAs 11 and 21, respectively, and become signals in analog quantities.

The converted signals of these analog quantities are multiplicative
The signals are input to DA12 and DA22, respectively. On the other hand, the coordinates x and y of each bright spot from the center of the character are stored in the multiplication type DAs 12 and 22 as digital signals △x and △, respectively.
y, and therefore these multiplication types
The DAs 12 and 22 output analog output signals equal to the products A.x and B.y, respectively. Next, output signals of analog quantities equal to these products A x and B
3 is input. At this time, the multiplication type DA13,2
3, command signals By and Bx including deformation rates Q and P are also input at the same time, respectively. As a result, the products Q・(A・x),
An analog quantity output signal equal to P.(B.y) is obtained.

Now, in this way, multiplication type DA12, 13,
Ax, BQx, output from 22 and 23, respectively
The analog quantity signal equal to the product of By and BPy is added to the sum Ax+BPy by the adder circuit 14 and summed by the adder circuit 24.
Analog quantities equal to AQx + By, that is, transformed character signals △Xa, △Ya for deflecting the CRT beam to coordinates is added to and output.

As explained above, this deformed character signal generation circuit generates a signal that deflects the CRT beam to coordinates Xa,
△Ya is occurring. Moreover, this linear transformation can be expressed by the following equation.

X=Ax+BPy Y=AQx+By Therefore, when the deformation rates P and Q are both 0 and A and B are both 1, a normal character without deformation is obtained. At this time, the vertical component y is simply deleted in order to obtain the coordinate value X of each base axis component, for example, the horizontal component. Therefore, compared to the conventional method of adding vertical components y with opposite polarities and canceling them out, the vertical component y can be eliminated very easily and accurately, and the same can be done for other directional components as well. , it is possible to obtain the correct true character.

Next, referring to FIGS. 3 and 4, an example of a specific configuration of the multiplication type DA used in FIG. 2 will be explained.

In Figure 3, R, 2R, 4R, 8R...2
^n-1R is a weighted resistance; S ₁ , S ₂ , S ₃ ,
S ₄ ...S _o is a switch; T ₁ , T ₂ , T ₃ , T ₄ ... T _o
is the input terminal of the digital input signals B ₁ , B ₂ , B ₃ , B ₄ ...B _o ; T is the reference voltage input terminal into which the analog input signal V _R is input; OA is the operational amplifier; R _F is the resistor; T ₀ is the output terminal that sends out the output e ₀ .

In this multiplication type D/A, resistors R, 2R, 4R...
Since each has its own weight, the flowing current also has its own weight. And the output e ₀ is given by the following formula.

e ₀ = V _R・R _F /R {B ₁・2゜＋B ₂・2 ^-1 +B ₃・2 ^-2 +B ₄・2 ^-3 +...B _o・2 _-o+1 } However, B ₁ , B ₂ . . . as B _i, B _i =1 or 0. By the way, in the configuration shown in Figure 3,
Since the input digital value is limited to either positive or negative, the present invention uses a multiplication type DA that can input both positive and negative values digitally, for example, a multiplication type DA having the configuration shown in FIG. 4. is used.

In Figure 4, 30 is an analog input signal
A multiplication type DA as shown in FIG. 3 which inputs ANL and a digital signal ABS corresponding to the absolute value of the digital input signal DGT; 31 is the digital input signal DGT.
A decoder circuit that obtains a digital signal ABS for the absolute value, a sign (positive or negative) bit signal SN, and a zero value signal ZR; 32 is a normal amplifier; 33 is an inverting amplifier; SW ₁ and SW ₂ are switches. be.

In this multiplication type DA, switch SW ₁ is switched to the plus side P, plus side P, or minus side M depending on whether the input digital value is a positive value, zero value, or negative value, and switch SW ₂ is switched on or off. , becomes conductive. Therefore, if the digital value DGT has a positive value, the output of the non-rotating amplifier 32, that is, the output whose polarity is not inverted, is obtained, and if it has a negative value, the output of the inverting amplifier 33, that is, the output whose polarity is inverted, is obtained. , furthermore, if the value is zero, the output OUT will become zero.

Incidentally, the decoder circuit 31 can also be provided inside the control device CNL.

FIG. 5 is an example of printing obtained by the present invention,
The right italic modified characters a and d, in which most of the bright spots of the characters rotate clockwise around the base point 0, and the left italic modified characters b and c, in which the bright spots of most of the characters rotate counterclockwise, are shown. Further, these modified characters have the original original characters in a square area indicated by a dotted line, and when transformed, they are displayed in a parallelogram area included in the square area.

Such deformed characters can be obtained by instructing the deformation rate as follows.

In the case of a, A=1-P, B=1, P>0, Q=0 In the case of b, A=1+P, B=1, P<0, Q=0 In the case of c, A=1, B=1-Q , P=0, Q>0 In the case of d A=1, B=1+Q, P=0, Q<0 As can be seen from the above description, according to the present invention,
In addition to being able to obtain various italicized characters with a simple circuit configuration, the original characters can also be obtained in accurate shapes even though some of the calculations are performed in an analog manner.

In addition, the present invention is a multiplication type shown in FIG. 3 or 4.
Not limited to using DA, and other than phototypesetting
It can also be applied to devices using CRT.
Furthermore, it is obvious that characters deformed only in the vertical and horizontal directions, such as long and flat characters, can also be obtained.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a display unit of a phototypesetting apparatus to which the present invention can be applied, FIG. 2 is a block diagram of a modified character signal generation circuit according to the present invention, and FIGS. 3 and 4 show an example of the configuration of a multiplication type DA. The figure shown in FIG. 5 is a diagram showing an example of print output according to the present invention. DEF ₁ ...Main deflection circuit, DEF ₂ ...Sub deflection circuit, AD...Analog addition circuit, CRT...Cathode ray tube, 11, 21...Digital-to-analog conversion circuit (DA), 12, 13, 22, 23 ... Multiplying digital-to-analog conversion circuit (multiplying DA), 14,2
4...Addition circuit, △X, △Y...Digital signals corresponding to characters, Sx, Sy, Bx, By...Command signals containing transformation rates of digital values, △Xa, △Ya...
Modified character signal, OA... operational amplifier, SW ₁ , SW ₂
...Switch, 32...Normal amplifier, 33...Inverting amplifier.

Claims (1)

[Claims] 1. A virtual orthogonal coordinate system is provided in which the center of each character output to the CRT is the base point, and deflection signals (△X, △Y) corresponding to the coordinates x, y of each bright spot of the real character are provided. and the deformation rates A, B, P, Q (A, B, P, Q are real numbers), and move each bright point to the coordinates X, Y where X=Ax+BPy, Y=AQx+By, A deformed character signal generating device that outputs a deformed character signal diagonally parallel to either the X-axis or the Y-axis, wherein the means for generating the deformed character signal combines the deflection signal and the deformation rate. a first multiplier that inputs and multiplies and outputs a signal proportional to the product Ax, By; inputs and multiplies the output signal of the first multiplier by the deformation rate, and outputs a signal proportional to the product AQx, BPy; a second multiplication means for outputting a signal; inputting the output signals of the first and second multiplication means;
an addition means for outputting the deformed character signal proportional to the sum Ax + BPy, AQx + By; the input deflection signal and the deformation rate are converted into digital values, and the first multiplication means outputs the digital value of the deformation rate; using a pair of digital/analog arithmetic circuits that converts into an analog quantity and generates an analog output obtained by multiplying the analog quantity by the digital value of the deflection signal; Analog multiplication circuit 1 that multiplies the output from each by a digital value of another deformation rate.
1. A deformed character signal generating device characterized by using a pair of deformed character signals, and a circuit for inverting the positive and negative of the output thereof according to the sign bit of the digital value of the deformation rate.