JPS60257655A - Picture processor - Google Patents

Abstract

PURPOSE:To attain ease of picture processing with less memory capacity by obtaining an address of 8 points near a branching point detecting a two-dimensional picture data subjected to thinning processing and obtaining a code value representing a position of a point having logical 1 of a noted point near the 8 points. CONSTITUTION:A characteristic point detecting circuit 6 detects an end point and a branch point in a thinned picture and its address data is stored in a data memory 8. An end point detecting circuit 9 uses a picture element having logial 1 near the 8 branching points as a tracking end point and its address data and that of the branching points are stored in a tracking end point table. Thus, the memory capacity of a thinning picture memory required is less and the address calculation to read the value of the noted picture element near the 8 points is omitted, then the picture is processed very easily and surely.

Description

[Detailed Description of the Invention] This invention converts input binary image data into thin lines,
The present invention relates to an image processing apparatus that can request the address of a point sequence obtained by this method.

[Prior art]

A conventional image processing apparatus of this type is shown in FIG. FIG. 1 is a block diagram showing a conventional image processing apparatus. In the figure, 1 indicates binary image data,
An image data input device for inputting to the image processing device; 2 an image memory for storing all image data; 3 a thinning circuit for thinning all of the image data stored in the image memory 2; 4 storing thinned image data. 5 is a pixel erasure circuit that sets the value of any one pixel of the image data stored in the thinned image memory 4 to zero; 6 is a pixel erase circuit that sets the value of any one pixel of the image data stored in the thinned image memory 4 to A feature point detection circuit that detects a pixel serving as a feature point and stores address data of this pixel; 7 is a point string processing processor that stores address data of a point string in the image data stored in the thinned image memory 4; 8; is a data memory that stores address data of the point sequence determined by the point sequence forming processor 7. FIG. 2 is a schematic diagram showing eight neighboring image data in the image processing apparatus shown in FIG.

Now, the address data described above is the X coordinate and the X coordinate in the two-dimensional image data. 1st line.

The X coordinate of the pixel in the first column is iS, and the X coordinate is j.

For a pixel with a value of 1, the value P to be divided by the following equation (1) is 2°6.
8, this pixel is defined as a feature point.

However, fQ), f(z),..., f(
8) is the pixel of interest f(0) and 8, as shown in Figure 2.
This is the value (0 or 1) of a nearby pixel. Also, f (9)
= f (1). Among the feature points, those with p=2 are defined as end points, and those with P=6 or Us are defined as all branch points, and the two are distinguished. Furthermore, in the thin line image, a dot sequence is a series of 8 pixels having a value of 1. The tracing process to obtain all the address data of the point sequence is performed for each line segment. A line segment is a sequence of points between feature points. However, there are no feature points in the middle of the line segment.

FIG. 3 is a diagram showing a dot sequence in the thinned image stored in the thinned image memory in the image processing apparatus of FIG. 1.

Next, the operation of the conventional image processing apparatus shown in FIG. 1 will be explained. The feature point detection circuit 6 detects all end points and branch points in the thinned image, and stores the address data in the all data memory 8.

Further, in the thin line image memory 4, end points are given odd labels of 3 or more, and branch points are given even labels. As shown in FIG. 3, the value assigned to each pixel is the result of labeling. Next, the point sequence processing processor 7 traces the point sequence in the thinned image at the point where the end point or the branch point hits, with all the end points as starting points. At this time, in order to detect all the next pixels, derive the addresses of the eight neighboring pixels of the pixel of interest, and calculate the value of the pixel indicated by each address.
IV1] Read from the glandular image memory 4. If this read value is 2 or more, it is known that the point is an end point or a branch point.

Since the conventional image processing device is configured as described above,
In the thinned image memory 4, 2 bits or more per pixel
''2, which had the disadvantage of requiring a large amount of memory. Furthermore, in order to read out all the values of the eight neighboring pixels of the pixel of interest, it is necessary to calculate addresses for each of the eight neighboring pixels, which has the disadvantage that the image processing becomes extremely complicated.

[Summary of the invention]

This invention was made for the purpose of improving the shortcomings of the above-mentioned conventional systems. Sasai 1. Find the addresses of the 8 neighboring points of the detected bifurcation point in the two-dimensional image data, find the code value indicating the position of the point with value 1 among the 8 neighboring points of the point of interest, and calculate the 8th point of this point.
By outputting the address data of neighboring points and tracing the address data of the point sequence with the value 1 in the thinned two-dimensional image data for each line segment,
The present invention provides an image processing device that can easily and reliably perform image processing while reducing the memory capacity of the thinned image memory required.

[Embodiments of the invention]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 4 is a block configuration diagram showing an image processing device that is an embodiment of the present invention, and the same parts as in FIG. do.

In the figure, structures designated by numerals 1 to 8 are the same as those shown in FIG. Reference numeral 9 indicates an end point detection circuit that detects all pixels having a value of 1 among the 8 neighboring pixels of the branch point detected by the feature point detection circuit 6, and stores the address data in the entire data memory 8; As shown in Figure 2, input the address data of the pixel f(0) of interest, and
If (1) is 1, is it 1? , if f(2) is 1, then 2,
If f(3) is 1, set 3; if f(4) is 1, set 4; if f(5) is 1, set 5; if f(6) is 1, set 6; f( If 7) is 1, then 7, and if f(8) is 1, then 8, f (1).

f(2), f(3), f(4), f(5), f
(6), f(7), f(0 if all 8 are 0)
This is a 3×3 code circuit that outputs . In addition, 11 is
Input the address data (x, y) of the pixel of interest and the output value of the 3 x 3 code conversion circuit 10 (hereinafter abbreviated as 3 x 3 code value), and confirm that the 3 x 3 code value is 1. If so, the address data (x-1,)'-1) is changed to 3x3 code value 2.
If the 3x3 code value is 3, the address data (X+1, y-1) is set. If the 3x3 code value is 4, the address data (x+1) is set.
．． y), and if the 3×3 code value is 5, then the address data (x +1- + y +1)? , if the 3×3 code value is 6, the address data (x r y +1) is
If the 3×3 code is 7, the address data (x-1
. FIG. 6 is a schematic diagram showing the contents of the tracking end point table obtained by the end point detection circuit in the image processing device shown in FIG. 4. , FIG. 7 is an explanatory diagram showing a procedure for determining pixel addresses in the image processing apparatus of FIG. 4.

Next, the operation of the image processing apparatus shown in FIG. 4, which is an embodiment of the present invention, will be described. The feature point detection circuit 6 detects all end points and branch points in the thinned image, and stores the address data in the data memory 8. The end point detection circuit 9 stores the address data of the branch point and the address data of the branch point in a tracking end point table as shown in FIG. 6, with pixels having a value of 1 in the 8 vicinity of the branch point as tracking end points. . In Fig. 5, the pixels indicated by ■ are the end points, and the pixels indicated by mu are the tracking end points. In Fig. 6,
Flag 1 has the value O if the endpoint or tracking endpoint has been tracked.
If it is tracked or not tracked, it has a value of 1. I cut it,
(For tracking) End point address data (X+ +y+ L(
Xz +3'2 L(X3 +Ys L(xt+y4
) + (X5 +Ya) + (X6+ye) are the pixels 122 and 13 shown in FIG.
It represents address data of 1 pixel, 142 pixels, 151 pixels, 169 pixels, and 17 pixels. Flag 2 has a value of 0 if there is an end point.
If there is a tracking end point, each has a value of 1.

Further, the address data of the feature point is the address data of the pixel 18 which is the eight neighboring branch points for the tracking end point whose flag 2 has the value 1. The point array processor 7 is
After the pixel erasing circuit 5 sets the values of the pixels indicated by ♦ and △ to 0, the entire point sequence is traced from the end point or the tracking end point in the thinned image.

The procedure for determining the address of the next pixel at this time will be explained using FIG. When the pixel indicated by the arrow in FIG. 7 is the pixel of interest, the address data of the pixel of interest is set to 'fi=(x, y). Pixels surrounded by dotted lines in the figure have already been tracked, and 1st shift is 0. The 3×3 code conversion circuit 10 focuses on the pixels indicated by the arrows in the figure, and calculates S(
Performs all ×3 encoding processing and outputs 3 × 3 code I direct 3. The address data calculation circuit 11 manually inputs the address data (x, 'y) of the pixel of interest and the 3×3 code value 3, and outputs the address data (x+1.y-1)k.

This address data is the address data of the next pixel of interest. The pixel erasing circuit 5 receives address data (x+
1, y~1) is set to 0. 3×3
When the code value is 0, the address data of the pixel of interest and the value of flag 1 in the tracking end point table are 1.
All comparisons are made with the address data of each end point, and the X coordinate,
Find all coordinates whose differences are within 1. If the address data found in this way is for the end point,
This end point is the end point of the line segment currently being traced. 1. If the address data found is for the tracking end point, the address data of the feature point is the address data of the end point of the line segment currently being tracked. The value kOK of flag 1 in the tracing end point table is set for the end point or tracing end point that is the start point or end point of the traced line segment. When the tracing process for one line segment is completed, in FIG. 6, find all the endpoints or tracing endpoints whose flag 1 is 1, and set this (- as the starting point of the next line segment to be traced. Tracing endpoint table) The above tracking process is performed until all of the flags 1 become O.

As is clear from the above description, according to the image processing device according to the present invention, in the thinned image memory 4 from which all addresses of a point sequence are to be calculated, only one bit of memory is required per pixel, and There is no need to perform address calculation to read out the values of pixels in the 8 neighborhood.

〔Effect of the invention〕

As explained above, the present invention provides an image processing device that includes:
In order to find the address of the point sequence obtained by thinning the input 2D image data, find the addresses of 8 points in the vicinity of the detected branch point in the thinned 2D image data, and calculate the point of interest. Find the code value indicating the position of the point with the value 1 among the 8 neighboring points of this point, output the address data of the 8 neighboring points of this point, and calculate the sequence of points with the value 1 in the thinned two-dimensional image data. Since the address data can be read by tracing each line segment, the memory sensitivity of the thinned image memory required is reduced, and it is also possible to Since all address calculations can be omitted, all image processing can be performed extremely easily and reliably, which is an excellent effect.

[Brief explanation of drawings]

FIG. 1 is a block configuration diagram showing a conventional image processing device, FIG. 2 is a schematic diagram showing 8 neighboring image data in the image processing device shown in FIG. 1, and FIG. 3 is a block diagram showing the image processing device shown in FIG. In the apparatus, FIG. 4 is a block diagram showing the entire dot sequence in the thinned image stored in the thinned image memory, and FIG.
In the image processing apparatus shown in the figure, FIG.
In the image processing apparatus shown in the figure, FIG. 7 is a configuration diagram showing gk of the tracking end point table obtained by the end point detection circuit.
5 is an explanatory diagram showing a procedure for calculating pixel addresses in the image processing apparatus of FIG. 4. FIG. In the figure, 1... Image gater input device, 2... Image memory, 3... Thinning circuit, 4... Thinning image memory, 5... Pixel erasing circuit, 6... Feature point detection. circuit,
7... point sequence processor, 8... data memory, 9...
...End point detection circuit, 10...3x3 code conversion circuit, 1
1: Address data calculation circuit, 12 to 18: Pixel 0. In each figure, the same reference numerals indicate the same or equivalent parts. Agent Masuo Oiwa Figure 1 Figure 2 Figure 3 Figure 4 Figure 6 Figure 7

Claims (1)

[Claims] means for inputting two-dimensional image data, means for storing this two-dimensional image data, means for thinning the stored two-dimensional image data, and values of arbitrary image data of the thinned two-dimensional image data. 2o; means for detecting all end points and branch points in the thinned two-dimensional image data and determining addresses; Then, we focused on a means of detecting all points with a value of 1 and assigning addresses, and we focused on an arbitrary point in the thinned two-dimensional image data, and found a point with a value of 1 among the 8 neighboring points. A means for outputting a code value indicating which one is, an address of an arbitrary point in the thinned two-dimensional image data, and a code value determined by focusing on this point are input, and the code value of this point is inputted. means for outputting address data of 8 neighboring points; means for tracing and checking address data of a series of points having a value of 1 in the thinned two-dimensional image data for each line segment; An image processing device comprising address data and means for storing the address data of the point sequence.