JPH0656617B2 - Labeling method for labeling processor - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a labeling processor for assigning numbers (labels) to identify a plurality of objects existing on one screen, and is particularly suitable for high-speed processing. Regarding processors.

BACKGROUND OF THE INVENTION In an image processing device using a visual sensor such as an ITV camera, a labeling process for numbering and distinguishing a plurality of objects in one screen is important.

There are several methods for labeling, but a method suitable for labeling an image read out in a raster scan pattern like an ITV camera is disclosed in Japanese Patent Laid-Open No. 57-67987. There is a method of cutting out pixel data of a local region (for example, vertical 2 × horizontal 3 pixels) into a raster scan pattern and processing it.

In this method, as shown in FIG. 2, the same object may be given different numbers at first as separate objects. This is because it is known that they are the same object at the point (JOINT point) where the separated numbers merge later, so the relationship of the separated labels is stored in the label relationship table (LRT) at this point. The process of creating an LRT while attaching such a temporary label is called temporary labeling. Subsequent to this temporary labeling, the LRT is analyzed by software, and a label conversion table (LTT) for final labeling is created. This is called table conversion. Next, based on this LTT, the temporary label is converted into the final label. This is called relabeling.

Conventionally, in order to obtain a label image, a temporary label obtained by the process of temporary labeling is temporarily stored in an image memory to obtain a temporary label image, and then this temporary label image is used to obtain L
The final label image was obtained by referring to the TT table.

FIG. 3 (a) shows the respective hardware configurations of temporary labeling, which is the processing phase of the labeling, and FIG. 3 (b), the relabeling.

First, the hardware configuration required for the temporary labeling is from the binary image memory 4B in which the original image is stored, the labeling processor 3 including the table LRT700 for storing the relationship of the separated labels, and the labeling processor 3. It is a grayscale image memory 4G1 for storing the output temporary label.

In the relabeling, the labeling processor 3 having the LTT 800 created by the table conversion as the lookup table configuration and the grayscale image memory 4G1 in which the temporary label image is stored are indispensable.

That is, in the labeling method described above, in addition to the labeling processor 3, a grayscale image memory 4G1 for storing a temporary label image which is an intermediate result of the labeling is indispensable, which makes the system compact, There was a problem that it hindered price reduction.

The grayscale image memory depends on the size of the image and the maximum number of labels, but in any case, a large-capacity memory (for example, the size of the image is 512 × 512 pixels in the maximum, the maximum number of labels is 256). In case of, it becomes 256K bytes)
Is necessary.

The second problem is that the internal structure of the labeling processor 3 is different between temporary labeling and relabeling.

Figure 3 shows the labeling processor 3 for temporary labeling.
As shown in (a), the binary image memory 4B is input, and the temporary label is output to the grayscale image memory 4G1. In relabeling, the grayscale image memory 4G1 is input as a table-up backup process.

As described above, in the two processing phases, the data path inside the labeling processor 3 is different, and the internal configuration becomes complicated.

[Object of the Invention]

An object of the present invention is to provide a labeling method for a labeling processor that realizes labeling without requiring a grayscale image memory for storing a temporary label which is an intermediate result of labeling, and that enables downsizing and cost reduction. It is in.

[Outline of Invention]

The present invention does not store a temporary label that has been conventionally required in temporary labeling, stores only the relation of separated labels in the label relation table LRT, and converts the label into a final label by LRT information in the table conversion. A conversion table LTT is created, and in the relabeling process, the temporary label is output with the same configuration as the temporary labeling, and the table conversion is performed by the LTT for the output to obtain the final label. is there. This eliminates the need for a grayscale image memory for temporary label storage during temporary labeling, which is an intermediate result of labeling, and enables relabeling with the exact same configuration as temporary labeling, thus simplifying the configuration of the labeling processor. , Downsizing and cost reduction are possible.

Example of Invention

 An embodiment of the present invention will be described below.

FIG. 1 shows a system configuration of an image processing apparatus including the labeling processor 10. Video of ITV camera 6 is A / D
The converter 5 digitizes it into one bit (the object is "1", the background is "0"), and the binary image data 8 is output. Two
The value image data 8 is input to the binary image memory 4B or the image processor 3 including the labeling processor 10. The processed image data 99 which is the processing result of the image processor 3 is subjected to calculation such as cumulative processing in the histogram processor 15.

The input of the image processor 3 can be selected from either the binary image data 8 or the memory read data 7 which is the read data from the binary image memory 4B.

The binary image memory 4B, the image processor 3, and the histogram processor 15 are controlled by the system processor 1.

The internal structure of the labeling processor 10 is, as shown in FIG. 4, (1) binary image data 8 output in the raster scan direction from the ITV camera 6 or the binary image memory 4B, or
Image cutout unit 100 that cuts out the local area of the memory read data 7 of 2 pixels in the vertical direction and 3 pixels in the horizontal direction (2) A circuit unit that controls label generation by the local area pixel data 20 of 3 × 2 pixels from the image cutout unit 100 20
0 (3) The previous raster label 70 from the label relation table LRT 700 is input, and based on the control signal 30 from the label generation control unit 200, (i) the segment label SEG55 of the target pixel (ii) the 3 × 2 pixel of the target pixel Of the existing labels, the maximum label MAX label 60 and the minimum label MIN label 65 are output. Label generation unit 300 (4) Label line buffer 500 for delaying SEG55 by one raster (5) Control from label control unit 200 A label relation table LRT 700 in which the MAX label 60 at the time of label merging (JOINT point) is used as a table address and the MIN label 65 is written as table data according to the signal 30. Therefore,
This table 700 shows the relationship between the labels of the same object.
It is stored as an X-MIN type. Label line
The output label 75 of the buffer 500 is given to the label generating unit 300 as the label 70 of the previous raster one line before through the LRT 700. The MAX / MIN writing and the conversion of the output label 75 of the label line buffer 500 are time-divisionally processed via the multiplexer 600.

(6) Label conversion table LTT800 for converting the previous raster label 70 from the LRT700. The output of the LTT 800 is output as the output data of the labeling processor 10.

(7) In accordance with the command signal 30 of the label generation control unit 200, M
The AX / MIN labels 60 and 65 are compared with each other, and are composed of seven parts of a label separation detection unit 900 for storing the label separation occurrence and the label when they do not match, and are controlled by the system processor via the system bus 2.

A method of labeling the present labeling processor 10 will be described below.

[1] Temporary labeling (1) The same segment number SEG is assigned to consecutive objects (this continuity is called a segment) in the raster being processed.

(2) When the above segment merges with the object on the upper screen of the screen, that is, the previous raster (this is called the JOINT point), the maximum two labels that merge are independent of SEG,
Keep the minimum value as the MIN label. At this time, MA
If X ≠ MIN, MAX of label relation table LRT
Write the MIN value to the address.

(3) Therefore, at the first point of the segment (this is called the START point), a new label number (this is called NEW LABEL) is assigned and MAX and MIN are also set to NL. In addition, S
If you already JOINT at the point, SEG, MAX, M
The merge label of the previous raster is assigned to IN.

(4) At the end point of the segment (this is called the END point), the MIN label at that time is written in the SEG address of the LRT.

(5) The label of the previous raster is converted to the minimum label by SEG in LRT. Therefore, in the MAX and MIN writes of (2), since the smallest labels updated most recently are compared, the probability of occurrence of separation can be made very small.

[2] Table conversion This is executed by software in the system processor 1, and the following processing is performed.

(1) Based on the information of the LRT, the temporary label at the time of temporary labeling is set so as to be converted into a label having the minimum value (this is called a root label) in the temporary label.

(2) Set the LLT so that the root label is converted into a consecutive numbered label.

[3] Relaben rig Performs exactly the same operation as during temporary labeling. The difference from the temporary labeling is that the output data 9 output from the labeling processor 10 at this time is the final label. This principle is shown in FIG. In addition, in the LRT700 and LTT800 in the labeling processor, those marked with a circle show the route label.

Binary image data 8 or memory read data 7 as shown in the figure is input to the labeling processor 10. At that time, by the table conversion of [2], the LRT700
Contains data for converting the temporary label into a root label.

Of the objects A to D included in the input image of FIG. 5, the labels C 3, 4, and 5 are assigned to the object C as temporary labels, and the minimum label 3 among them is the root label,
LRT70 so that labels 4 and 5 are route labels 3.
Set to 0. Similarly, the object D is set in the LRT 700 so that the temporary label 7 becomes the root label 6. Since the final route label is assigned to simple shapes such as the objects A, B, and E even in the temporary labeling, the route label is not set by the software of the LRT 700.

Further, the LTT 800 is set with a value for converting the root label into a continuous label by the table conversion of [2]. That is, in the front raster label 70 output from the LRT 700, the temporary label is always converted into the root label. Therefore, in the case of FIG.
2, 3, 6, and 8 are input to the LTT 800. LTT8
At 00, the values are set so that the route label 6 is converted into 4 and the route label 8 is converted into 5.

In the labeling processor 10 including the LRT 700 and the LTT 800 in which the above data is set,
The same operation as the temporary labeling is performed, and the label generator 3
The temporary label output from 00 is input to the LRT 700 via the label line buffer 500. LRT70
At 0, the temporary label is converted to the root label and LTT80
Input to 0. Then, in the LTT 800, the root label is converted into a serial number and becomes the final label, and the output data 9 is output. As a result, as shown in FIG. 5, labels 1 to 5 are assigned to the objects A to D, respectively. At this time, at the JOINT point, all temporary labels should be equal because they have been converted to root labels, but they can be separated (because they are originally the same object, they become different labels). There is a slight sex. Therefore, if MAX ≠ MIN at the JOINT point, the separation detection unit 90
Then, the separation detection flag is set, and MIN is written in the MAX address of the LRT. That is, the separation label is stored in the LRT. Therefore, if this flag is checked after relabeling and the process of [2] is repeated again, labeling without complete separation can be always performed.

In the configuration shown in FIG. 4, the separation flag is detected only at the JOINT points after the second appearance of the segment.

The control of the label generation control unit 200 will be described in detail for the case of a 4-connected image. The 4-connection means that it is considered that the object is connected only to the pixel above, below, left, and right with respect to the pixel of interest. Therefore, from the above description, the label generation control unit 200 may control the segment SEG generation, the MAX and MIN label generation, and the LRT registration (writing) according to the pattern of 3 × 2 pixels, as shown in FIG. In FIG. 6, x is don't car.
e and ◯ indicate “1” pixels.

The embodiment of the present invention has been described above. (1) When the final label does not have to be a continuous number, in other words, when only the conversion to the root label is necessary, the LTT is unnecessary.

(2) It is clear that even if MAX and MIN described in the present invention are replaced, a completely normal labeling operation can be performed, and it is possible to handle with a function other than the size of the label value.

(3) For the final label, it is not necessary to store the label corresponding to the pixel in the grayscale image memory by directly performing histogram processing and extracting the area for each label, the center of gravity for each label, and the like. In other words, in the system configuration including the labeling processor of the present invention, the grayscale image memory having a large amount of hardware is completely unnecessary.

The above can be said.

〔The invention's effect〕

According to the present invention, since it is not necessary to store a temporary label which is an intermediate result of labeling, it is possible to delete the grayscale image memory necessary for this, and it is possible to realize a small-sized and low-cost labeling processor.

Further, since the temporary labeling and the relabeling can be realized by the hardware having the completely same structure, a labeling processor having a simple structure can be realized.

[Brief description of drawings]

FIG. 1 is a system configuration diagram of an image processing apparatus according to the present invention, FIG. 2 is a diagram showing a general labeling procedure, FIG. 3 is a diagram showing a general labeling hardware configuration, and FIG. FIG. 5 is a block diagram of the labeling processor of FIG. 3, FIG. 5 is a diagram showing the operation principle of the labeling processor of the present invention, and FIG. 6 is a diagram showing the pattern of the label generation control unit of the 4-connected image. . 4B ... Binary image memory, 10 ... Labeling processor, 100 ... Image cutout section, 200 ... Label generation control section, 300 ... Label generation section, Label line buffer 50
0, 700 ... Label relation table LRT, 800 ... Label conversion table LTT, 900 ... Label separation detection unit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Kazuka Asada 5-2-1 Omika-cho, Hitachi City, Ibaraki Prefecture Hitachi Ltd. Omika Plant, Ltd. (72) Inventor Kazuki Fujiwara 5-chome, Omika-cho, Hitachi City, Ibaraki Prefecture 2-1 Hitachi Ltd. Omika Factory, Hitachi Ltd. (56) Reference JP-A-57-67987 (JP, A)

Claims (1)

[Claims] 1. A binarization of the labeling target image, comprising a label relation table for storing a relation between an object in the labeling target image and the label, and a label conversion table for converting the label into a final label. In a labeling method of a labeling processor for obtaining a final label in two image scans for an image memory in which an image is stored, in a first image scan for the image memory,
If a temporary label is added to an object in the captured binary image, the relationship between the object and the label is stored in the label relationship table, and if there are multiple temporary labels attached to the same object,
The label relation table is set so that the root label, which is the label having the smallest value among the temporary labels, is stored as the label of the same object, and further, the label conversion table is set so that the root label has a continuous number. Setting, in the second image scanning for the image memory,
A temporary label is added to the object in the captured binarized image, a route label is added to the object to which the temporary label is added based on the label relation table, and the added route label is added. A labeling method of a labeling processor, wherein a label converted based on the label conversion table is output as a final label.