WO1985002252A1

WO1985002252A1 - Apparatus for measuring circumference of figure

Info

Publication number: WO1985002252A1
Application number: PCT/JP1984/000549
Authority: WO
Inventors: Yuichi Hirota
Original assignee: Yokogawa Medical Systems, Ltd.
Priority date: 1983-11-18
Filing date: 1984-11-15
Publication date: 1985-05-23
Also published as: JPH0128984B2; JPS60110084A

Abstract

This circumference measuring apparatus is capable of obtaining, with a simple calculation mechanism, the circumference of an approximation polygon of which each side is constituted by a variable-length line segment which conforms to the shape of an original figure. The profile of the original figure displayed on the screen of a display device is traced by a manually-operated profile tracing means. Variations in each of the components of two-dimensional coordinates on the display screen generated by the profile tracing means are calculated by counters. The contents of each of the counters are read and reset to zero by a circumference calculation circuit, every set period of time which is determined by the clock period. The length of each segment is calculated from the read-out counts, and the circumference of the original figure is obtained by totalling the lengths of the segments thus obtained.

Description

Clear document Perimeter measurement device

(Technical field〕

The present invention relates to an improvement in a device for measuring a perimeter of a graphic displayed on an image display device, and more particularly to an improvement in a graphic perimeter measuring device using a polygonal approximation method.

[Background Art]

As a method of measuring the perimeter of a figure, there are a method of approximating an original figure to be measured with a polygon and a method of using pattern recognition.

In the method based on polygonal approximation, a quantized figure that resembles the original figure in an S-shape is created by extracting the outline and contours of the original figure, and calculating the perimeter of the approximated polygon to calculate the perimeter of the original figure. Seeking an approximate value for length. One way to race an original figure is to display it on a display and then use a coordinate input device such as a track pole, joystick, tablet, or pen to make a human race. Widely used. One side of the contour of the created approximate polygon is composed of one line segment in eight directions, and the sum of the lengths of all sides of this polygon is the approximate value around the original figure.

The measurement error due to the polygonal approximation includes the error due to the unevenness of the corners of the approximated polygon and the error between the (pixel) for quantization and the actual contour. The error due to the corners of the approximate polygon increases as the pixel is made finer, while the error due to misalignment increases as the pixel is made coarser. Due to these two contradictory error factors, there is a limit to the error reduction of such an approximation method.

As an improved version of the above-mentioned polygon approximation measurement method, an approximation polygon that connects pixels that are some distance apart rather than a polygon that connects the centers of two adjacent pixels in a digital figure There is a method of using a polygon. In this method, the error is reduced on average compared to the above method, but on the contrary, the error may be increased depending on the shape and size of the original figure. In the method using pattern recognition, the contour of the original pattern is compared with some basic patterns prepared in advance, the closest pattern is adopted, and the perimeter of this basic pattern is obtained. This method has been widely used recently. However, the applicable patterns are limited by the basic pattern, and if the number of basic patterns is increased, the amount of data to be stored will be enormous.

A technique for making the contour of the approximate polygon as close as possible to the contour of the original figure is disclosed in Japanese Patent Laid-Open Publication No. 57-74609. This technique is to sample the coordinates of a probe that is operated by a human to trace the contour of the original figure at a constant period according to the clock signal, and sample these coordinates and these coordinates. The line segment connecting the lines is displayed or recorded by a display device or a recording device. According to this technique, as is the case with human operations, the approximate polygons have many bends because they slowly race where there are many bends in the vergence of the original figure and quickly when there are few bends. Since it is represented by a fine line segment in a roller, and a rough line segment in a place where there is little bending, an approximate polygon with each side of a variable-length segment adapted to the shape of the original figure can be obtained. This publication makes no suggestion as to the measurement of the perimeter of the original figure, but if the perimeter is to be measured, two coordinates adjacent to each other in the coordinate sequence obtained by sampling are used. , It is necessary to calculate the distance between these coordinates, that is, the length of each side of the approximate polygon. For this reason, a means for storing the sampled coordinates one by one is required, but a perimeter measuring device that does not require such a means and has a simple configuration as much as possible is preferable.

[Disclosure of Invention]

An object of the present invention is to provide a perimeter measuring apparatus capable of obtaining the perimeter of an approximate polygon having each side of a variable-length line segment adapted to the shape of an original figure by a simple calculation mechanism. is there.

In order to achieve this object, the present invention provides a display screen in which the ^ -shape of the original figure displayed on the screen of the display device is raced by a manually operated girder-race race means, and the ^ -clause race means is generated. The change amount of each component of the above two-dimensional coordinate is counted by force counter, and this counter

O PI The count value is determined by the clock cycle-Periodically, it is read by the perimeter calculation circuit and reset to 0, and the read count value is used to calculate the line segment length. The perimeter of the original figure is calculated by the picture length of the line segment.

[Brief description of drawings]

FIG. 1 is a block diagram showing the configuration of a graphic perimeter measuring apparatus according to an embodiment of the present invention.

Figure 2 shows an example of measurement by the device of the present invention.

Figure 3 shows a time chart of the measurement example.

[Best Mode for Carrying Out the Invention]

In Figure 1, a rack ball 1 is connected to a coordinate calculation circuit 2 and an XY counter 3. A coordinate memory 4 is connected to the coordinate calculation circuit 2. The perimeter calculation circuit 5 is connected to the x Y counter 3. A clock signal source 6 and a peripheral length memory 7 are connected to the peripheral length calculation circuit 5. Perimeter memory 7 is connected to Character 1: 1: Element 8. The coordinate operation circuit 2 and the character generator 8 are connected to the video memory 9. A digital / analog converter (hereinafter DZA converter) 10 is connected to the video memory 9, and a CRT display device 1 1 is connected to the D ZA converter 10. An image pickup device 1 is connected to the CRT display device 1 Ί. 2 is connected.

The rack rack pole 1 is equipped with a signal generation circuit and generates a pulse signal according to the rotation of the rack rack ball. This pulse signal contains χ τ (rotation to the right), X— (rotation to the left), y + (rotation to the up), and y— depending on the rotation direction of the rack rack 1.

There are four types (rotation downward).

The coordinate calculating circuit 2 calculates the force on the CRT display device Ί 1 moved by the rack rack 1--the digital coordinate of the sol, based on the pulse signal and the stored contents of the coordinate memory 4. The coordinate memory 4 stores the coordinates of the cursor calculated by the coordinate calculation circuit 2. The XY counter 3 counts the four types of pulse signals generated by the rack rack 1. The perimeter calculation circuit 5 receives the clock signal from the clock signal source 6 each time

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— WIPO _ The count value of the x Y counter 3 is read, the segment length is calculated from the count value by the calculation as described below, and the memory contents of the perimeter memory 7 are added to this, and the value is again stored in the perimeter memory 7. , Χ Υ Counter 3 count value is set to 0. Such a perimeter calculation circuit 5 is realized by, for example, a microprocessor. The clock signal source 6 generates a clock signal with a constant period. The perimeter memory 7 stores the perimeter calculated by the perimeter calculation circuit 5. The character generator 8 generates a character signal for displaying the contents stored in the perimeter memory 7 on the CR T display device 1 1 in numerical form. The video memory 9 stores the force-sol image signal at the address ffl ¾ at the coordinate calculated by the coordinate calculation circuit 2, and stores the character signal generated by the character generator 8 at an appropriate address. The image signal and the character signal are given to the CRT display device 11 as an analog luminance signal through the DZA comparator 1Q. As a result, the force-sol is displayed at the position on the screen specified by the coordinate information, and the number corresponding to the character signal is displayed at an appropriate position on the display screen. The imaging device ^! 2 images the object whose perimeter is to be determined and displays it on the CRT display device 1-.

A measurement operation'by the graphic perimeter measuring device configured as above will be described. This device basically uses the polygonal approximation method.

The figure to measure the perimeter is imaged by the imaging device Ί 2, and this is displayed on the CRT display device Ί. The figure displayed on this CRT display device 11 is the original figure for perimeter measurement. The operator races the contour of this original figure by moving the force sol with the rack rack Ί. The rack rack 1 outputs a pulse signal to the coordinate calculation circuit 2 and the XY counter 3 with the 0 rotation.

Coordinate operation circuit 2 The digital coordinate information is updated based on the output pulse signal, and this digital coordinate information is displayed on the CRT display device 11 as a moving cursor through the video memory 9 and the DZA converter Ί 0.

On the other hand, the output pulse signal of the rack rack Ί is measured by the XY counter 3. The count values χ +, χ —, y T, y — of the XY counter 3 are read by the perimeter length calculation circuit 5 at a constant cycle according to the clock, and then reset to 0. The perimeter calculation circuit 5 uses the count value read from the XY counter 3 to calculate the segment length S by the following equation. Calculate one-'

AS = (∑X + —∑X—) ² + (y + --∑y

Fig. 2 shows an example of segment measurement such as .., and its time chart is shown in Fig. 3. These figures show that the convergence boundary line T is raced by the cursor moved by the rack rack Ί, The figure shows the case where the clock signal is generated at the time of the race of the positions of P _Q , P ₅ and P ₉ . During the first clock cycle, Rikiichi Sor races for 5 pixels and for the next clock cycle it races for 4 pixels. The trace of force-sol is displayed on the CRT display device 11 according to the race, but what is required to measure the perimeter is the pixel where the cursor is at the time when the CJC signal is generated. Only P ₀ , P ₅ and P ₉ . Therefore, the ^ contour line T is approximated by the two-segmented lace line C.

Let AS ·] be the segment of the first clock period and S ₂ be the segment length of the second clock period.

twenty two

.AS 广 A / 3 ^l + 2

= 3 .-6 0 5

= 2

Becomes However, the unit is a relative unit where the interval of pixels is Ί. Such a segment length is sequentially calculated from the start to the end of measurement and accumulated in the perimeter memory 7 to obtain the perimeter of the original figure.

As described above, in the apparatus for measuring the perimeter of a figure according to the present invention, the length of one side of the approximate polygon obtained by lacing the original figure is measured by the segment moved at fixed time intervals. There is. Therefore, the length of the segment changes depending on the human race speed. That is, the length of the segment is short in the part where the race speed is low, and conversely, the length is long in the part where the race speed is fast. This is because when a human races a certain figure, the race speed is high for the part with a large radius of curvature and the straight line part, and slow for the part with a small radius of curvature and the complex part. Can be used. That is, one side with a large radius of curvature has a long length, and Approximate polygons can be created such that the length of one side of the short part is short, and it is possible to reduce the error when measuring the circumference of various types of figures. Then, such a device is realized by the present invention with a simple configuration.

In addition, if the pixels are made finer and the sensitivity of the rack pole is increased so as to accommodate it, the error can be further reduced.

In this embodiment, an example in which the original figure is displayed on the CRT display device has been shown, but the present invention can be practiced on other display devices.

Further, as a means for racing the original figure, the present invention can be implemented by any type of racing device such as a joystick, a tablet, a light pen, etc. in addition to the rack rack ball.

| ¾ C'OO O a

[Industrial availability] ..

As described above, the present invention enables highly accurate perimeter measurement of a figure without being affected by the shape. As a result, medical applications such as quantitative measurement of morphological abnormalities, geographical applications such as topographical measurement by aerial photography, engineering applications such as CAD, etc. can be considered, and they have effects in a wide range of fields. .

'― OMPI, Claim display means having a display screen (Ί 1>,

The image display means (1 2) for displaying the original figure whose circumference is to be measured on the display screen of this image display means,

The image display means races the outline of the original figure displayed on the display screen by manual operation, and outputs the variation signals of each component of the two-dimensional coordinates on the display screen of the raced part. And the means of racing (Ί)

Counting means (3) for counting the output signal of this race means for each component of the two-dimensional coordinates, and

The count value for each component of the two-dimensional coordinate of the counting means is read at fixed time intervals determined by the clock signal, and the count values are reset to 0, and based on the read count value, the polygonal shape approximated to the original figure is read. Perimeter calculation means (5), (6〉. (7), which calculates the length of a piece and sequentially accumulates and adds the calculated values each time.

An apparatus for measuring the perimeter of a figure, comprising:

. The race means generates a change signal of each component of the two-dimensional coordinates for a change in one direction and a change in the opposite direction.

The counting means counts the change signals in the opposite directions of the change signals of the respective components of the two-dimensional coordinates output by the above-mentioned lace means,

The perimeter calculating means calculates the length of a piece of polygon approximated to the present figure based on the difference between the count values of the two-dimensional coordinate components read from the counting means in opposite directions. Is,

A device for measuring the perimeter of a figure in the scope of claims.

The device for measuring the circumference of a figure according to claim 2, wherein the means for racing is a rack ball. The perimeter measuring device for a figure according to claim 1, wherein the perimeter calculating means includes a storage means for storing a cumulative addition value of the calculated values.

An image display means (11>) having a display screen,

An image is displayed on the display screen of this image display means, and the original figure whose circumference is to be measured is displayed.

Ο ΡΙ An imaging means (12) for displaying an original figure whose perimeter should be measured on the display screen of this image display means,

The image display means races the outline of the original figure displayed on the display screen by manual operation, and outputs each variation signal of each component of the two-dimensional coordinates on the display screen of the race part. The means of racing (1)

Cursor display means (2), (4), (9), (10) for displaying the portion on the display screen in which the lace means is displayed as a cursor on the image display means,

Counting means (3) for counting the output signal of the above-mentioned race means for each component of the two-dimensional coordinates,

The count value for each component of the two-dimensional coordinates of the counting means is read at fixed time intervals determined by the clock signal, and the count values are reset to 0, and the original figure is approximated based on the read count value. Perimeter calculation means (5), (6). (7) for figures that calculate the length of a rectangular piece and successively accumulate and add the calculated values each time.

An apparatus for measuring the perimeter of a figure, comprising:

The cursor display means is.

Based on the output signal of the lacing means, the coordinate calculating means for obtaining the two-dimensional coordinates on the display screen of the part where the lacing means is lacing, and the address corresponding to the coordinates obtained by this coordinate calculating means. Pide-age memory means for storing cursor image information,

A digital analog conversion means for converting the force image information stored in the video memory means into an analog luminance signal and supplying it to the image display means;

A device for measuring the perimeter of a figure according to claim 5, including.

The device for measuring a perimeter of a figure according to claim 6, wherein the coordinate calculation means includes coordinate storage means for storing the calculated coordinates.

An image display means (Ί 1) having a display screen,

Image capturing means (12) for displaying the original figure whose circumference is to be measured on the display screen of this image display means,

O PI And a race means (1) for performing a race and outputting each variation signal of each component of the two-dimensional coordinates on the display screen of the race portion.

Counting means (3) for counting the output signal of this lacing means for each component of the two-dimensional coordinates, and

The count value for each component of the two-dimensional coordinate of the counting means is read at fixed time intervals determined by the clock signal, and the count values are reset to 0, and based on the read count value, the polygonal shape approximated to the original figure is read. A perimeter calculation means (5), (6), (7) for calculating the length of one piece and successively accumulating and adding the calculated values each time,

Perimeter display means (8), (9>, (10) for displaying the perimeter calculation value obtained by the perimeter calculator on the screen of the image display means,

An apparatus for measuring the perimeter of a figure, comprising:

The perimeter display means

A perimeter measurement value is given from the perimeter calculation means, and this measurement value is converted into a character signal for numerical display.

A video memory means for storing a character signal given from the character generator means,

Digital-analog conversion means for supplying the character signal stored in the video memory means to the image display means as an analog luminance signal,

A device for measuring the perimeter of a graphic according to claim 8 including.

Image display means (1 Ί) having a display screen,

An imaging means (12) for displaying an original figure whose perimeter is to be measured on the display screen of this image display means,

Cursor display means (2), (4), (9), (10) for displaying a portion on the display screen in which the lace means is on the image display means as a cursor, When,

The count value for each component of the two-dimensional coordinates of the counting means is read at fixed time intervals determined by the clock signal, and they are reset to 0, and the original figure is approximated based on the read measured value. Around ^ operation that calculates the length of a polygon piece and successively accumulates and adds the calculated values each time? Steps (5), (6), (7.),

Perimeter display means (8), (9), (10) for displaying the perimeter calculation value obtained by the perimeter calculation means on the screen of the image display means,

An apparatus for measuring the perimeter of a figure, comprising:

Claims

Instructions based on Article 19

With regard to the term of claim 1, all the technologies disclosed in the reference are amended so as to be included in the preamble.

Regarding the three items of the scope of the claims, the reference signs of the drawings are added, and the dependent party is changed to the paragraph Ί of the claims.

With respect to paragraph 4 of the claims, reference numerals of the drawings are added.

Paragraph 8 of the claim was amended so as to be dependent on claim 1. Paragraphs 2, 5, 6, 7, 9 and 10 of the claims are deleted because those characteristic parts are disclosed by reference.

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