JPH0773332B2 - Area designation method - Google Patents

Description

The present invention relates to a method of designating an area using a coordinate input device.

[Conventional technology]

Conventionally, in an image processing apparatus such as a copying machine, there is a method of inputting area coordinates by a ten-key as an area specifying means on an original in order to realize a trimming function for extracting only an arbitrary area on the original, a masking function for erasing, etc. . However, in this method, there is a problem in operability because a procedure for reading coordinates by a medium or the like is required and the number of keystrokes is large. As a method for covering these drawbacks, there is a method using a two-dimensional coordinate input device such as a digitizer.

[Problems that the invention is trying to solve]

In a system using a two-dimensional coordinate input device such as a digitizer, a desired area can be directly designated on the original, so that the operability can be greatly improved. However, in this method, on the contrary, there is a problem that the degree of freedom of area designation exceeds the processing capability of hardware, for example, an area having a shape that cannot be trimmed is designated.

[Means for solving problems]

In order to solve the above problems, the present invention provides an area designating method for an image processing apparatus having a two-dimensional coordinate input device,
The coordinates of each corner of a desired rectangular area or a desired area composed of a combination of rectangular areas are sequentially input, the input coordinates are stored in a memory, and the input start point coordinates, end point coordinates, and 2 from the start point are input. A region for correcting the coordinates of the start point or the coordinates of the end point stored in the memory based on the vector direction to the second input point and the vector direction from the input point immediately before the end point to the end point There is a designation method.

[Action]

According to the present invention, when the coordinates of each corner of a rectangular area or an area in which rectangular areas are combined are input using a two-dimensional coordinate input device such as a digitizer by the above method, the data input by the operator is appropriately used. To correct.

〔Example〕

An embodiment of the present invention will be described in detail below with reference to the drawings.

1-2 is an external view of a copying apparatus to which the present invention can be applied. The document reading unit 101 has a document table glass (not shown), a 2: 1 optical system including an illumination lamp and a mirror, a lens, a CCD, and the like.
While the optical system is sub-scanning, the original image is photoelectrically converted and output as an electric signal. The printing unit 102 is a so-called laser printer, which receives an electric signal from the reading unit 101, scans the photoconductor with a modulated laser beam, and prints by electrophotography. The reading unit 101 includes an operation unit 103, a coordinate input device 104 that also functions as a document holder, and a coordinate input pen 105.
FIG. 1-1 shows a view of the coordinate input device 104 as viewed from above. 106 is an effective coordinate input surface, 107 is an abutting reference point for placing a document 114 on the input surface, 108 is an area designation key for inputting that area designation is to be performed, and 109 is a clear key for canceling a series of input coordinates. , 110 ends the area specification input O
K key, 111 is a trimming mode selection key that outputs only the specified area, 112 is a masking mode selection key that erases only the specified area, and 113 is an image separation mode selection key that outputs the inside of the specified area by processing different from the outside. .

These operation examples will be described.

As shown in the figure, the operator places the original 114 against the reference point 107, places it in the area designation mode with the key 108, and turns the respective corners indicated by black circles of the area surrounded by the dotted line by the input pen 105 clockwise or left. After inputting all around, press OK key 110 to complete the input. After that, the contents of processing to be performed on the designated area are designated by the keys 111, 112, 113.

FIG. 3 shows a schematic block diagram of the copying apparatus of this embodiment.
302 is an image reading unit. The image reading unit 302 has a CCD, a signal amplification circuit, an A / D conversion circuit, and a shading correction circuit, and the corrected signal is input to the image processing unit 303.

The image processing unit 303 temporarily stores the image signal in the shift memory, then performs image processing such as scaling, moving, trimming / masking density conversion, and the like, and outputs the result to the external unit 312 as a VIDEO signal. Although the external unit 312 is assumed to be a so-called laser printer in this embodiment, it may be a controller such as an electronic file or facsimile and a memory device. Image signal V is sent to the external unit via cable 313.
In addition to IDEO, for example, a serial signal line composed of multiple signal images
Serial signals are sent by SRAL to control the entire system. When the external unit 312 is a laser printer, the horizontal sync signal BD is received from the printer and the clock generator is used.
A clock for internal operation is generated by 304 and given to the above-mentioned reading unit 302 and processing unit 303.

CPU 301 is a ROM 30 that stores control programs and control data
5. A RAM 306 for storing processing data and the like and a timer circuit 307 are provided, and in addition to controlling communication with the reading unit 302, the processing unit 303, and the external unit 312, a fluorescent lamp driver circuit 309 for illuminating an original document. And a motor driver circuit 308 for driving the optical system, the operation unit 311 and the coordinate input device 310.

FIG. 4 shows a block diagram of the coordinate input device 310.

The timing circuit 402 generates a clock with an internal oscillator and gives it to the address counter 403. The address counter 403 counts while the switch built in the pen 412 is pressed. During the counting operation, first, the X decoder 409 operates to sequentially apply the pulse voltage to the X direction electrode of the input surface 411 for two rounds, and then the Y decoder 410 operates to similarly apply the pulse voltage to the Y direction electrode of the input surface 411 in sequence. Two rounds of dynamic skiing. When the switch of the pen is turned on on the input surface 411, a voltage is induced in the pen by capacitive coupling when the scanning in the X direction and the Y direction reaches the pen position, and the pen input signal is obtained, and the amplifier 404
Is amplified by. The count value is set in the X register 406 by the pen input signal of the first round of X direction scanning,
X register 406 according to the pen input signal during the second scan
The contents of the above and the count value are compared by the comparator 405, and if they match, a match signal is output to the CPU 401. Similarly, in the Y direction as well, the Y register 408 during the first round scan is set, and if the second round scan time comparator 407 compares and a match is found, a match signal is output to the CPU 401, and the CPU 401 outputs two match signals. When the value is obtained, coordinate values can be fetched from the X and Y registers and notified to the main CPU 301 by, for example, serial communication. When the X register 406 and the counter value do not match, it is determined that the input is invalid. The same applies to the Y direction.

FIG. 5 shows a circuit diagram related to the inside of the image processing unit 303, particularly the shift memory. The shift memory is provided with a shift memory for two lines, but since the control is common, FIG. 5 shows the control configuration of only one shift memory. The write address counter 904 is an address counter when writing data in the shift memory 907, and the read address counter 905 is an address counter when reading data from the shift memory 907. An address selector 906 receives a command from the CPU 301 via the I / O port 901, selects one of the address signal of the write address counter 904 and the address signal of the read address counter 905, and addresses the shift memory 907. Is. The I / O registers 902 and 903 are registers for the CPU 301 to give a preset value to the write address counter 904 and the read address counter 905, respectively.

Write address counter 904, read address counter 9
Reference numerals 05 are both down counters to which the WST signal and the RST signal for instructing the start of the count operation are input, and the write clock WCLK to the shift memory 907 and the read clock RCLK from the shift memory are input.

915 and 916 are exclusive OR gates for determining the image area, and the signal OF is a signal for controlling it. When it is 1, ST counter 912, E
The inside of the frame determined by the N counter 913 is masked, the outside of the frame is used as an output image, and the inside of the frame is masked as the output image when O is set.

Reference numeral 910 is an AND gate for controlling output of image data output from the shift memory 907 and converted into a binary signal through the density processing unit 908. Reference numeral 917 is for determining whether the mask portion is output as white or black. At the gate, BB outputs a black signal when it is 1 and a white signal when it is 0.

911 is a video output for the image output by the gates 910 and 917.
, 909 is an exclusive OR gate for controlling black and white inversion of image data, and IN is a signal for controlling it, and when 1 is an original image, it is inverted when 0.
Each signal is output by the CPU 301 in a mode designated by the operator.

The ST counter 912 and the EN counter 913 are a start bit counter and an end bit counter for outputting an image only to a predetermined area, respectively.
PU301 presets the count data for the gate.

The flip-flop 914 is set by the count-up of the ST counter 912 and reset by the count-up of the EN counter 913.

For example, when the OF signal is 1, when the Q of the F / F 914 becomes 1 by the count up of the ST counter 912, the output of the gate 915 becomes 0, and the gate 910 continues until the EN counter 913 counts up.
Is not output and is masked. Instead, the output of the gate 916 is 1 during that time, so that when the BB signal is 1, the gate 917 is 1 and the gate 911 outputs 1 to serve as a black mask. Conversely OF
When = 1 and BB = 0, the white mask is applied. Further, when OF = 0, the outputs of the gates 915 and 916 are 1,0 during that time respectively. Therefore, when BB = 1, the outside of the trimming area is black, and when OF = 0 and BB = 0, the outside of the trimming area is white.

The present embodiment is effective when performing the editing process such as trimming or masking on a rectangle or a region in which rectangles are combined by using the means described above.

A rectangle or a combination area of rectangles is an area surrounded only by line segments parallel or perpendicular to the main / sub scanning axes, and it is sufficiently practical to limit the editing target to such an area. Moreover, it is useful in that the editing function can be provided at a low cost without using a large capacity memory.

Based on this limitation, the operator discretely inputs coordinates so as to surround a desired area, and the line segment connecting these coordinates in the input order is as horizontal or vertical as possible with respect to each main / sub scanning axis. Should be entered as follows.

However, in reality, it is impossible to input two points that are connected horizontally and vertically by freehand pen input in view of the practical resolution of the coordinate input device. Correct the coordinates.

FIG. 2 illustrates a schematic example of the area designation method according to this embodiment.

First, press the clear key to clear all the preset coordinates.

Input the first point P ₁ (PX ₁ , PY ₁ ).

Input the second point P ₂ (PX ₂ , PY ₂ ). At this time, ｜ PX ₂ -PX
₁ ｜ and ｜ PY ₂ -PY ₁ ｜ are compared, and ｜ PX ₂ -PX ₁ ｜> ｜ PY ₂ -PY ₁
| So input point P ₂ is T ₂ (TX ₂ , TY ₂ ) ＝ (PX ₂ , PY
Correct to ₁ ).

Input the third point P ₃ (PX ₃ , PY ₃ ). At this time, since the corrected second point T ₂ and the third point P _{3 become} | PX ₃ -TX ₂ | <| PY ₃ -TY ₂ |, P _{3 is changed} to T ₃ (TX ₃ , TY _{3 as} shown in the figure. ) = (PX ₂ , PY ₃ )

The fourth point P ₄ (PX ₄ , PY ₄ ) is also (compared to the corrected third point T _{3
T 4 (TX 4, TY 4} ) = and correcting (PX _4, PY _3). Similarly, the fifth point P ₅ (PX ₅ , PY ₅ ) becomes T ₅ (TX ₅ , TY ₅ ) = (PX ₄ , PY ₅ ), and the sixth point P ₆ (PX ₆ , PY ₆ ) becomes T 5. ₆ Correct to (TX ₆ , TY ₆ ) = (PX ₆ , PY ₅ ).

Press the OK key when you have finished entering each corner of the desired area.

When the OK key is entered, the first point P ₁ (PX ₁ , PY ₁ ) and the corrected final point T ₆ (TX ₆ , TY ₆ ) = (PX ₆ , PY ₅ ) are used to make the first point P by the end point processing described later. Correct ₁ (X ₁ , Y ₁ ) to T ₁ (TX ₁ , TY ₁ ) = (PX ₆ , PY ₁ ).

By correcting and controlling the input coordinates in the above procedure, the operator's desired area can be configured by vertical line segments and vertical line segments.

FIG. 6 shows a detailed flow chart of the above-mentioned correction processing. First, the counter i on the RAM indicating the number of input coordinate points is cleared to 0 (601). If there is a coordinate input (602), the X component is set in the areas PXi, TXi on the RAM and the Y component is similarly set in PYi, TYi (603). i = 0, that is, if it is the first point (60
4) The counter i is incremented to wait for the second input (615). If i ≧ 1 (604), the corrected coordinate (TXi _-1 , TYi _-1 ) one point before and the input coordinate (PXi, PYi) of this time
The absolute values α and β of the differences for each of the X and Y components are obtained (605).

The operator compares the magnitudes of α and β based on the premise that the line segment connecting each point is horizontal and vertical with respect to the axis as much as possible (606). If α <β, it is determined that the operator tried to input coordinates so that the operator would be parallel to the Y-axis
The Y coordinate PYi of Pi is directly adopted as TYi, and the X coordinate PXi
Cancels and adopts the previous X coordinate TXi _-1 as TXi (608). Conversely, if α> β, it is determined that the operator has entered coordinates so that the operator is parallel to the X axis, and the X of the point of interest Pi is determined.
The coordinate PXi is adopted as it is as TXi, the Y coordinate PYi is canceled, and the Y coordinate TYi _{-1 one} point before is adopted as TYi (60
7). The input point Pi is corrected to Ti by the correction of 607 and 608, and the line segment After becoming parallel to the X-axis or Y-axis, And the line before it Check if is orthogonal. If i = 1, only one line segment is generated, so the counter i is set to 1 to wait for the third point input.
Increment (609,610,615). TXi if i ≧ 2
_-2 = TXi, that is, whether the two line segments of interest are on the same line segment parallel to the Y axis (612) or TYi _-2 = TYi, that is, the two line segments of interest are on the same line segment parallel to the X axis (611) is checked, and if NO, the counter i is incremented by 1 to wait for the next input (615). If YES, combine these two line segments into one line segment A new sum vector (613,614). In other words, the input Ti _-1 one point before is canceled and Ti is treated as Ti _-1 , and since the Ti input is waited again, the counter i is not incremented and the next coordinate is waited. After incrementing the counter i to wait for new input, the line segment generated by the latest input point Ti _-1 Is all the line segments that have been entered Check how many times you intersect with (616). The detailed flow will be described later.

If no intersection is detected as a result of the intersection detection, the next coordinate input is awaited (617,602). If it intersects twice or more, Ti _-1 is invalidated, and the counter i that should wait for re-input is decremented by 1 (617 → 619). If it intersects only once, at least one closed area has been created, so wait for the OK key input to finish the area specification or the clear key input to cancel the point Ti _-1 . If there is a clear key input, the counter i is decremented by 1 and waits for re-input (618 → 619). If there is an OK key input, the process proceeds to the end point process described later (624).

If there is a clear key input when there is no coordinate input in step 602, the counter i is decremented by ₁ to cancel the latest input point Ti _-1 and wait for re-input (623). OK
If there is a key input (624), the process proceeds to the end point process described later (62
Four). When the result area of the end point processing is confirmed, the processing ends.

FIG. 7 shows a control flow of crossing detection, which will be described below. First, the counter k on the RAM indicating the number of crossings is cleared to 0 (701). When i <4, at most four points, that is, only three sides have been input, so the detection processing ends. When i5, i-4 is set to the counter j on the RAM for the cross check (703). After that, the values A, B, C, D are obtained using the coordinates of the points Ti _-1 , Ti _-2 , Tj, Tj _-1 (704, 705, 706, 707). The function F shown below is used for the value calculation.

F (Tm, Tn) =-1: When TXm = TXn or TYm = TYn 0: When TXm <TXn and TYm <TYn 1: When TXm <TXn and TYm> TYn 2: TXm> TXn and TYm> TYn When 3: TXm> TXn and TYm <TYn Function F classifies the positional relationship between the two points Tm and Tn into five cases and assigns values, which is illustrated in Fig. 8. Ie 2
Vector generated from points Tm and Tn Value is "-1" when is parallel to the X-axis or Y-axis, and "0" when it is at the upper right.
Is a function that outputs “1” when it is in the upper left direction, “2” when it is in the downward left direction, and “3” when it is in the downward right direction.

If any one of the values A, B, C, D is "-1", Since they touch each other, they do not intersect, so j is updated (708 → 709). If there is no “−1”, like 711 to 718 below,
It is checked whether or not the values A, B, C and D take the values "0", "1", "2", "3", in that order, in ascending or descending order. FIG. 9 shows an example in which YES is determined in step 711.

When the example of Fig. 9 is rotated clockwise by 90 ° each, 712,
There is a positional relationship of four points that is determined as “YES” in 713 and 714.
In addition, the example of FIG. When the positional relationship is such that it is folded back in line symmetry, the result is determined to be YES in step 715, and when it is rotated counterclockwise by 90 ° each, 716, 717 and 718 are determined to be "YES". When it is determined that the intersection occurs in the above eight cases, the intersection counter k is incremented by 1 in step 719, Crossed The counter value j-1 that specifies the value of is set to l. Update j in step 709, and continue checking until j <0 in step 710.

Decrementing j by 2 at step 709 is the same as when decrementing by 1. Because it is parallel to.

The end point processing flow is shown in FIG. 12 and will be described below.

First, the counter i is checked (1001), and if i <2, only two points can be input at most, and the area cannot be determined (1012), and the process is terminated to wait for point input again. If i3, the counter i value is decremented by 1 so as to indicate the latest input point number (1002).

Then the vector from the starting point T ₀ to the second point T ₁ The direction code Do of is determined based on Fig. 10 (1003), and the vector from the point Ti _-1 toward the latest point Ti as well. Similarly, the direction code Di _{−1 of} is determined (1004). afterwards,
According to the end point processing type table shown in FIG. 13, the end point processing type is selected from the positional relationship of the two direction codes Do and Di _-1 , the coordinates TX ₀ and TY _{0 of the} point To, and the coordinates TXi and TYi of the point Ti. Then, the processing according to the processing content described in Table 1 is performed (1005).

Example of correction according to the processing contents for each type listed in Table 1
Shown in Figure 14. A side ▲ ▼ is generated by the start point (Sp) To and the end point (Ep) Ti newly determined by performing the processing of Table 1, and No reprocessing is required if it is at a right angle with, otherwise it is re-step 100 using the corrected To, Ti and i.
Perform the following processing (1006 → 1001).

After securing the coordinates of each corner that can configure the area by the above procedure, the line segments formed by connecting each point from To to Ti in order will not intersect each other, or the above-mentioned intersection detection logic on each side Correspondingly executed (1007), if even one intersection intersects the area is indeterminate and wait for point input again or wait for input point by clear key input (1008 → 1012).

In step 1009, the point where the Y component has the minimum value from point To to point Ti and the X component has the minimum value
Ts is set as the area origin (1009), and the area origin Ts is re-designated as To. Hereafter, a series of points is traced clockwise from the new To, and T ₁ , T ₂ , ..., Ti are newly numbered (1010), Confirm the area (1011) and finish the area specification.

Processing examples of steps 1009 and 1010 are shown in FIGS. 11-1 to 11-3.

Next, an embodiment of editing the area determined by the above procedure will be described with reference to FIGS. 15-1 to 15-3.

First, let the point sequence To, ..., Ti be the X axis, Y as shown in Fig. 15-1.
Coordinates KX ₀ , KX ₁ , KX ₂ , KX ₃ , and KY obtained by projecting on the axis
Calculate ₀ , KY ₁ , KY ₂ , and KY ₃ . Then, when the coordinate area is divided by these four coordinates, nine zones Z ₀₀ , ... Z ₂₂ can be defined in FIG. 15-1. As can be seen, some of these nine zones actually make up the designated area. In order to distinguish the zones forming this designated area, each zone is redefined by its barycentric coordinates. That is, Zij = (ZXij, ZYij), (i = 0,1,2, j = 0,1,2), ZX
ij = (kxi + KXi _{+ 1} ) / 2 and ZYij = (KYj + KYj + 1) / 2. Based on the following data KX _{0 to} KX ₃ , KY _{0 to} KY ₃ , and Z _{00 to} Z ₂₂ , it is determined whether or not each zone is included in the designated area as shown in FIG. 15-2.

A matrix-like illustrated MAP is configured in an area on the RAM.
In this MAP, odd rows and odd columns correspond to zone boundaries, and elements defined by even rows and even columns correspond to the zones.

First, the direction code 0,1,2,3 of each side is set to M in the order of the point sequence T ₀ , T ₁ , ... Ti previously obtained from the elements in the first column and the third row corresponding to the point To.
Fill in the corresponding elements of AP. After that, for all the elements on the matrix showing each zone, whether there is a code "0" in the upward direction, a code "1" in the downward direction, a code "2" in the leftward direction, and a code "3" in the rightward direction. Find out. The zone Zij is included in the area when all four conditions are satisfied, and is not included when any one of the conditions is missing. In the example of FIG. 15-2, the Δ mark is included in the area, and the X mark is not included in the area. In this example, the matrix MAP has been described as 7 × 7, but in general, there is a margin N within the range allowed by the memory capacity.
XM. Also, each element may be at most 4 bits.

Zones Z ₂₀ , Z ₁₀ , Z ₀₁ , which form the area as described above,
Z _11, edit processing as the 15-3 diagram by means described in FIG. 5 When Z _21, Z ₂₂ is determined.

When the optical system moves in the sub-scanning direction Y, first, in the image destination A, both the previous ST counter 912 and EN counter 913 are set to 0, and at the point B advanced by KY ₀ , the ST counter is KX ₁ , EN counter KX. ₃ is set, and then ST counter KX ₀ and EN counter KX ₃ are set at point C where KY ₁ -KY _{0 has} advanced, and KY
_2- At ST point KX ₂ and EN counter KX at point D that has advanced KY _1
3 is set, and 0 is set to both ST counter and EN counter at the point E where KY ₃ -KY _{2 has} proceeded, and the optical system starts returning. In this way, for example, the image can be a valid image only inside the area, or it can be masked by invalidating it.

As another embodiment, for example, when the coordinates are corrected from α and β in step 606 of FIG.
Further, by providing a threshold value γ and correcting when the condition of γ> min (α, β) is satisfied, it is possible to more accurately grasp the intention of the operator. Also, in step 606 of FIG. 6, α = β
If more than one crossing is detected in step 617, if the area is uncertain in step 625,
The operability is further improved by notifying the operator of the fact that the input coordinate is invalid or that the coordinate input is further required by the display or voice.

〔effect〕

As described above, according to the present invention, the coordinates of each corner of the desired rectangular area or the desired area composed of a combination of rectangular areas are sequentially input, the input coordinates are stored in the memory, and the input start point is input. Based on the coordinates of, the coordinates of the end point, the vector direction from the start point to the second input point, and the vector direction from the input point immediately before the end point to the end point,
By correcting the coordinates of the start point or the coordinates of the end point stored in the memory, the area intended by the operator can be estimated, and the coordinates of the input point can be automatically corrected. You can specify the area.

[Brief description of drawings]

FIG. 1-1 is a diagram showing a coordinate input device, FIG. 1-2 is an external view of a copying device to which the present invention can be applied, FIG. 2 is a diagram showing an example of coordinate correction, and FIG. 3 is a schematic diagram of the entire device. Block diagram, FIG. 4 is a block diagram of the coordinate input device, FIG. 5 is a process block diagram relating to editing, FIG. 6 is a control flow chart for input coordinate correction, FIG. 7 is a control flow chart for intersection detection, and FIG. The figure is an illustration of the function F used for intersection detection. Fig. 9 is a diagram showing an example of intersection. Fig. 10 is a diagram showing direction codes of area edges. Figs. 11-1 to 11-3 are input point sequences. FIG. 12 is a diagram showing an example of rearrangement, FIG. 12 is an end point processing control flow chart after completion of coordinate input, FIG. 13 is a figure showing an end point processing type table, FIG. 14 is a figure showing an end point processing example, and FIG. 15-1. FIG. 15-3 is a diagram showing an example of editing processing.

Claims (3)

[Claims] 1. A method of designating an area of an image processing apparatus having a two-dimensional coordinate input device, wherein coordinates of respective corners of a desired rectangular area or a combination of rectangular areas are sequentially input, and the input coordinates are input. Based on the input start point coordinates, end point coordinates, vector direction from the start point to the second input point, and the vector direction from the input point immediately before the end point to the end point. An area designating method, characterized in that the coordinates of the starting point or the coordinates of the ending point stored in the memory are corrected. 2. The coordinates stored in the memory according to claim 1, wherein the line segment connecting two consecutively input points is horizontal or vertical to the coordinate axis. An area designation method characterized by correction. 3. The method according to claim 1, wherein it is determined whether or not a line segment connecting the Nth input point and the (N-1) th input point intersects with another line segment. An area designating method, wherein the Nth input point is invalidated when it intersects with two or more line segments.