JPH04156692A - Centroid calculation circuit for link area - Google Patents

Abstract

PURPOSE:To calculate the centroid at high speed by finding the X coordinate accumulation value, Y coordinate accumulation value, and histogram of an update label in parallel with processing to attach an update label unifying temporary labels. CONSTITUTION:Temporary label X/Y coordinate accumulation parts 1, 3 calculate the accumulation values of X/Y coordinates in a label area attached by a temporary labeling part 9 on the area of an image temporarily. Also, a temporary label histogram calculation part 5 calculates the histogram value of a label supplied to the area in the image by the labeling part 9. At this time, update label X/Y coordinate accumulation parts 2, 4 find the X/Y coordinate accumulation values based on the temporary and update labels found at a clustering part 14. Thereby, an update label centroid calculation part 7 calculates the coordinate of the centroid from the X/Y coordinate accumulation values and the histogram value found at the accumulation parts 2, 4 and an calculation part 6 at high speed.

Description

[Detailed Description of the Invention] [Summary] Regarding a center of gravity calculation circuit that calculates the center of gravity of a connected region in an image, the circuit calculates the cumulative X-coordinate value, cumulative Y-coordinate value, and histogram value of the provisional label in parallel with provisional labeling. , the cumulative X-coordinate value of the updated label in parallel with the clustering process that combines multiple provisional labels given to one region into one updated label based on the connection relationship of the partial regions to which the next provisional label has been given,
The purpose is to calculate the Y coordinate cumulative value and histogram value and calculate the center of gravity from these, and to quickly calculate the center of gravity in parallel with labeling each region in the image. a provisional labeling section that assigns a provisional label (temporary label); a provisional label A provisional label Y-coordinate accumulation section that calculates the cumulative value of coordinates and a provisional label histogram calculation section that calculates the histogram value of the region of the given provisional label assign a provisional label to the region in the image and calculate the provisional label. After calculating the X-coordinate cumulative value, Y-coordinate cumulative value, and histogram value for each time in parallel, 1, the Calculate the cumulative X-coordinate value, cumulative Y-coordinate value, and histogram value of the updated label from the sum of the cumulative coordinate value, cumulative Y-coordinate value, and histogram value, and calculate the cumulative X-coordinate value, histogram value, and cumulative Y-coordinate value of the updated label from these. It is configured to find the center of gravity based on the histogram value.

[Industrial Application Field] The present invention relates to a center of gravity calculation circuit that calculates the center of gravity of connected regions in an image. A process that uses image processing to identify multiple objects scattered in an image in parts inspection, blood cell testing, cell testing, etc. in the medical field, and calculates the graphical characteristics of each object, such as its size, position, and perimeter. is necessary. In particular, when determining the position of each object, it is desired to realize a circuit that can quickly determine the position of the center of gravity of a connected region.

[Conventional technology]

Conventionally, as a circuit for calculating the center of gravity of a connected region, as shown in the circuit example of FIG. 8, a labeling section 28 independently labels each region scattered in an image. Next, the histogram calculating unit 35 calculates the area of this labeled area as a histogram value for each label, and the X coordinate value accumulating unit 36 calculates the cumulative value of the X coordinate values of this labeled area for each label. The Y-coordinate value accumulator 37 calculates the cumulative value of the X-coordinate values of the labeled area for each label. Then, the center of gravity calculation unit 38 calculates the cumulative X coordinate of 4M for each label.
/ Histogram value, Y coordinate cumulative value / Histogram value was calculated, and the X coordinate value and X coordinate value of the center of gravity for each label were calculated.

[Problem to be solved by the invention]

As mentioned above, conventionally, for each label, the cumulative X coordinate value,
The Y coordinate cumulative value and histogram value were calculated, and the X coordinate cumulative value and Y coordinate cumulative value were each divided by the histogram value to calculate the center of gravity's X and Y coordinates, so it was possible to calculate each region for each label from the image. There has been a problem in that it takes a lot of time to calculate the center of gravity.

In parallel with provisional labeling, the present invention provides
Calculate the coordinate cumulative value, Y coordinate cumulative value, and histogram value,
The cumulative X coordinate value, cumulative Y coordinate value, and histogram value of the updated label are performed in parallel with the clustering process that combines multiple provisional labels given to one region into one updated label based on the connectivity of the partial regions that have been given the next provisional label. The aim is to calculate the center of gravity from these and to enable high-speed calculation of the center of gravity in parallel with labeling each area in the image.

[Means to solve the problem]

Means for solving the problem will be explained with reference to FIG.

In FIG. 1, a provisional labeling section 9 provides a provisional label (temporary label) to each region in the image.

The provisional label X-coordinate accumulator 1 calculates the cumulative value of the X-coordinates of the area of the given provisional label.

The provisional label Y-coordinate accumulator 3 calculates the cumulative value of the Y-coordinate of the area of the provided provisional label.

The provisional label histogram calculation unit 5 calculates the histogram value of the area of the provided provisional label.

The class linking unit 14 assigns a label (updated label) that summarizes the provisional labels of the connected areas.

The updated label gravity center calculation unit 7 calculates the gravity center based on the X coordinate cumulative value/histogram value and the Y coordinate cumulative value/histogram value of the updated label.

[Effect]

As shown in FIG. 1, in parallel with the provisional labeling unit 9 assigning a provisional label to each region in an image, the provisional After the label X coordinate accumulating unit 1 calculates the cumulative value of the X coordinate, the temporary label Y coordinate accumulating unit 3 calculates the cumulative value of the Y coordinate, and the temporary label histogram calculating unit 6 calculates the histogram value, the clustering unit 14 is the temporary label of the connected area Label that summarizes the temporary labels of the connected area (updated label)
In parallel with the process of assigning the temporary label, the X coordinate cumulative value, Y coordinate cumulative value, and histogram value of the updated label are calculated as the sum of the X coordinate cumulative value, Y coordinate cumulative value, and histogram value of these provisional labels, and from these, the updated label's The center of gravity is determined by the coordinate cumulative value/histogram value and the Y coordinate cumulative value/histogram value.

Therefore, in parallel with provisional labeling, the cumulative X-coordinate value, cumulative Y-coordinate value, and histogram value of this provisional label are calculated, and in parallel with the next clustering process, the cumulative X-coordinate value, cumulative Y-coordinate value, and histogram value of the updated label are calculated. By calculating the center of gravity from these, it becomes possible to calculate the center of gravity at high speed in parallel with labeling each area in the image.

〔Example〕

Next, the configuration and operation of the embodiment of the present invention will be explained in detail using FIGS. 1 to 7.

In FIG. 1, a provisional label It is something to do.

The provisional label Y-coordinate accumulating unit 3 calculates the cumulative value of the Y-coordinate values of each pixel in the region of the provisional label provisionally given to the region in the image by the provisional labeling unit 9.

The provisional label histogram calculation section 5 calculates the histogram value of the region of the provisional label provisionally given by the provisional labeling section 9 to the region in the image.

The updated label X coordinate accumulation unit 2 calculates the cumulative X coordinate value of the updated label (for example, the cumulative value). Here, the updated label is a label that combines the provisional labels of the connected areas (for example, it is the updated label A that combines the provisional labels 1.2.3 of the connected area in FIG. 3(C)).

The updated label Y coordinate accumulation unit 4 calculates the Y coordinate cumulative value of the updated label (for example, the Y coordinate cumulative value of the updated label A in FIG. 3(d)) based on the pair [temporary label, updated label] obtained by the clustering unit 14. value).

The updated label histogram calculation unit 6 calculates the histogram value of the updated label (for example, the histogram value of the updated label A in FIG. 3(d)) based on the pair [temporary label, updated label] obtained by the clustering unit 14. It is.

The updated label center of gravity calculation section 7 includes the updated label X coordinate accumulation section 2
, the center of gravity is calculated by the following formula il+, (2) from the cumulative X-coordinate value, cumulative Y-coordinate value, and histogram value of the updated label obtained by the updated label Y-coordinate accumulation unit 4 and the updated label histogram calculation unit 6. It is something.

X coordinate of center of gravity = (cumulative value of X coordinate of updated label) / (histogram value) (1) Y coordinate of center of gravity = (cumulative value of Y coordinate of updated label) / (histogram (2) The labeling unit 8 is a provisional labeling unit 9 that assigns a provisional label to each area of the binary image.The labeling unit 8 delays the binary image by one screen. A delay buffer 10 for processing, a label updating unit 11 that updates the temporary label given to each pixel in the connected area to an updated label based on the bare [temporary label, updated label], and a temporary labeling unit 9 for updating the N area. A connection relationship organizer 12 organizes connection relationships between provisional labels of connected areas among areas to which provisional labels have been assigned, and a label connection relationship stores direct connections between provisional labels organized by the connection relationship organizer 12. 1 compiled based on the storage unit 13 and the connection relationships between temporary labels taken out from the label connection relationship storage unit 13
The clustering unit 14 generates [temporary labels, updated labels] in which one updated label is paired with each provisional label.

Next, the operation of the configuration shown in FIG. 1 will be explained in detail in accordance with the order shown in the flowchart of FIG. 2 and with reference to FIG.

In FIG. 2, ■ is taken in pixel by pixel.

In this case, the temporary labeling section 9 captures the binary image shown in FIG. 1 pixel by pixel.

In (2), the temporary labeling unit 9 assigns a temporary label to each area based on the binary image captured pixel by pixel in (2). For example, as shown in Fig. 3 (a), the area of the binary image captured pixel by pixel is scanned line by line from left to right, and the provisional label is shown in the diagram, as shown in 1.2.3. granted to. Then, when the provisional labeling unit 9 assigns a provisional label with @, in parallel, the provisional label Calculate the cumulative value of the X coordinate by accumulating the Y coordinate for each pixel in the area of the provisional label to which the provisional label Y coordinate accumulation unit 3 has been added in ■.The provisional label histogram calculation unit 5 has added the provisional label in ■. The histogram value accumulated for each pixel in the area is calculated.

[Phase] determines whether one screen has finished. If YES, proceed to 0. If No, repeat @.

Through the above processing, a provisional label is assigned to each pixel of the region of the input binary image, and in parallel, the cumulative X coordinate value, cumulative X coordinate value, and histogram value of the pixels in the region to which this provisional label is given are calculated. .

In FIG. 2 O, there is a one-screen delay. During this time, the cluster linking process is performed in [phase], that is, the cluster linking section 14 in FIG.
gives one update label to the mutually connected provisional labels based on the connection relationship (for example, the connection relationship of temporary labels that have a direct connection relationship as shown in FIG. 3(b)-d),
Performs processing to generate a pair of [temporary label, updated label]. Parallel to this clustering process, in ■, the provisional label of the pair [temporary label, updated label] is input to the provisional label X coordinate accumulation unit 1, and the updated label is manually input to the updated label Temporary label X with 0 in front of the screen
The X-coordinate cumulative value obtained by the coordinate accumulator 1 is taken out, inputted to the updated label X-coordinate accumulator 2, and accumulated in association with the updated label for all pairs of [temporary label, updated label]. As a result, the cumulative X-coordinate value of the updated label is calculated (accumulated in the updated label X-coordinate cumulative table 46, 47 in FIG. 6). Similarly, in [Phase], of the pair (temporary label, updated label), enter the provisional label into the provisional label Y coordinate accumulation section 3, input the updated label into the updated label Y coordinate accumulation section 4, and move one screen forward. [Phase] indicates that the X-coordinate cumulative value obtained by the provisional label Y-coordinate accumulator 3 is extracted, inputted to the updated label Y-coordinate accumulator 4, and accumulated in association with the updated label. ]
This allows the updated label of X
Calculate the cumulative coordinate value. Similarly, input the provisional label of the pair [temporary label, updated label] into the provisional label histogram calculation unit 5 and input the updated label into the update label histogram calculation unit 6 in ■, and enter the provisional label with @ in the previous screen. The histogram values obtained by the label histogram calculation unit 5 are extracted, inputted to the update label histogram calculation unit 6, and accumulated in association with the updated label for all pairs of [temporary label, update label]. Thereby, the histogram value of the updated label is calculated.

Through the above processing, when a pair of [temporary label, updated label] is generated by the clustering process, the X coordinate cumulative value, the X coordinate cumulative value, and the histogram value of the updated label are calculated in parallel.

FIG. 2 O updates the label. This is because the label update unit 11 in FIG. 1 creates a correspondence table between the temporary label and the updated label based on the pair of [temporary label, updated label], and then creates a delay for one screen based on this correspondence table. A label image is generated in which a unique label is assigned to one connected region for the temporary label image. In parallel with this label update process, the update label centroid calculation unit 7 in FIG.
is the center of gravity (X
coordinates) = (X coordinate cumulative value)/histogram value...
・・・・・・・・・・・・・・・(3) Center of gravity (Y coordinate) = (
Y-coordinate cumulative value)/histogram value・・・・・・・・・・
...... Find (4). Then, the obtained X and Y coordinates of the center of gravity are passed to the MPU.

Through the above processing, the above (3
), (4) calculate the coordinates X and Y of the center of gravity.

FIG. 3 shows an example of calculating the center of gravity of a connected region according to the present invention.

FIG. 3(A) shows a temporary label image. In this method, a binary image is scanned line by line from left to right using a local window), and provisional labels 1.2.3 are sequentially given to areas where 1 appears.

FIG. 3(b) shows the connection relationship of the provisional labels in FIG. 3(a). Here, ■-3 and 2-3 indicate that provisional label 1 and provisional label 3, and provisional label 2 and provisional label 3 are in a connection relationship.

FIG. 3(c) shows a correspondence table. This is a pair [temporary label, updated label] generated by associating the temporary label and the updated label with one updated label assigned to the provisional label of the connected region.

Figure 3 (d) shows the cumulative X-coordinate value of the provisional label of each area,
It shows how the Y-coordinate cumulative value and histogram value are calculated, and the X-coordinate cumulative value, Y-coordinate cumulative value, and histogram value are calculated in association with the updated label. Xl, X2, and X3 are the provisional label 1 calculated by the provisional label X coordinate accumulation unit 1 in FIG.
．． This is the cumulative value of the X coordinate of 2.3. Also, X1+X2+X
3 is the cumulative X-coordinate value obtained for the updated label A, which is a compilation of the provisional labels 1.2.3 of the connected region.

Figure 3 (e) represents the center of gravity.

Next, the hardware circuits shown in FIGS. 4 to 7 calculate the cumulative X-coordinate value of the temporary label (FIGS. 4 and 5), calculate the cumulative X-coordinate value of the updated label (FIG. 6), and update the Calculation of the center of gravity of the label (FIG. 7) will be explained in detail.

FIG. 4 shows a circuit diagram of an embodiment of the temporary label X-coordinate accumulator.

(1) Temporary label value from temporary labeling section 9 in Figure 1 ■
a provisional label X-coordinate accumulation unit (even frame) 19 for calculating the cumulative value of the
Temporary label X-coordinate accumulation unit (odd frame) 2 that calculates the cumulative value of the X-coordinate of the provisional label value when the frame is an odd-numbered frame.
(2) Count the vertical interphase signal in FIG. 4 by inputting the provisional label value ■ of the pair of [temporary label, updated label] generated by the clustering unit 14 in FIG. When the circuit 21 counts and the frame is an even number (SL=O), the provisional label
1 selector 22, and on the other hand, when the frame is an odd number (SL=1), the provisional label This process of taking out the labels is repeated alternately, and the updated labels are inputted to the X-coordinate accumulating section 2 and accumulated in association with the above-mentioned pair of updated labels (FIG. 6).

FIG. 5 shows a circuit diagram of an embodiment of the provisional label X-coordinate accumulator for even (odd) frames. This shows the specific circuit of the circuit diagram in FIG. 4. Here, in response to the input of the provisional level value ■ from the provisional labeling section 9 in FIG. The X coordinate values of the provisional labels are accumulated in the provisional label X coordinate accumulation table 23 along the route shown. Then, in the next frame, in response to the input of the provisional label value ■ out of the pair [temporary label, updated label] from the class kling unit 14 in FIG. The X cumulative value of the provisional label accumulated in the above (1) is extracted from the provisional label X coordinate cumulative table 23 through the route shown by and outputted from the right side (inputted to the updated label X coordinate accumulator 2). While the even number frame
The X cumulative value of the provisional label is output from the right side along the route indicated by the dashed line. Following the operation of the even frames, in the odd frames, the temporary label Accumulate values.

The difference between the provisional label X-coordinate cumulative table 23 and the provisional label
Since the processing does not end within τ (time to process one pixel in a TV signal), 23 and 24 are switched and used every other pixel.

FIG. 6 shows a circuit diagram of an embodiment of the updated label X-coordinate accumulator. This is a specific circuit example of the updated label X-coordinate accumulator 2 in FIG.

(1) Of the pair [temporary label, updated label] from the clustering unit 14, the fifth label that has already described the provisional label
Input the cumulative X coordinate value of the updated label in the updated label X coordinate accumulation table 4G by inputting the provisional label ■ and taking it out along the route indicated by the dashed dotted line as input in Figure 6C. Accumulate. Following this operation for even frames, the same process is performed for the updated label X-coordinate accumulation table 47 for odd frames.

FIG. 7 shows a circuit diagram of an embodiment of the update label gravity center calculating section.

This is the X coordinate cumulative value from the updated label X coordinate accumulation unit 2 in FIG.
7) is input to ■, the X coordinate cumulative value from update label Y coordinate accumulation section 4 in FIG. 1 is input to [F], and The histogram value is input to @, and the division circuit 62.6
3, X coordinate cumulative value [F]/histogram value @-center of gravity (X coordinate) X coordinate cumulative value [F]/histogram value @=center of gravity (Y coordinate) is calculated and passed to the MPU.

By using the hardware circuit explained above using FIGS. 4 to 7, the temporary label in FIG. 4 (FIG. 5, which is a detailed version of FIG. In the 0th frame, the cumulative X-coordinate value of the label, and the cumulative X-coordinate value and histogram value of the temporary label are calculated using a similar circuit. The X-coordinate cumulative value, the X-coordinate cumulative value, and Calculate the histogram value. Furthermore, in the next frame, based on the calculated X-coordinate cumulative value, X-coordinate cumulative value, and histogram value of the updated label, the X-coordinate and Y-coordinate of the center of gravity are determined by dividing by FIG.

〔Effect of the invention〕

As explained above, according to the present invention, the X coordinate cumulative value, the X coordinate cumulative value, and the histogram value of this provisional label are calculated in parallel with the provisional labeling process, and the Coordinate cumulative value, X coordinate cumulative value,
Since the histogram value is calculated and the center of gravity is calculated from these as the X coordinate cumulative value/histogram value and the X coordinate cumulative value/histogram value, provisional labeling, clustering processing, and labeling of regions in the image are adopted. The center of gravity for each wI region is calculated in parallel with the update, and the center of gravity can be determined at high speed.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram of one embodiment of the present invention. FIG. 2 is a flowchart of a circuit for calculating the center of gravity of a connected region according to the present invention. FIG. 3 is an example of calculating the center of gravity of a connected region according to the present invention. Fig. 5 is a circuit diagram of an embodiment of the provisional label X-coordinate accumulation section for even (odd) frames. Fig. 6 is a circuit diagram of an embodiment of update label X-coordinate accumulation. Fig. 7 is an embodiment circuit of an update label centroid calculation section. FIG. 8 shows an example of a conventional circuit for calculating the center of gravity of connected regions. In the figure, 1: provisional label X coordinate accumulation section 2: updated label : Update label centroid calculation unit 8 Labeling unit 9 Temporary labeling unit 10; Delay buffer 11 Label updating unit 12; Connection relationship organizing unit +3; Label connection relationship storage unit 14: Class Kling unit

Claims (1)

[Claims] A center of gravity calculation circuit that calculates the center of gravity of connected regions in an image, comprising: a provisional labeling unit (9) that assigns a provisional label (provisional label) to each region in the image; a provisional label , a provisional label histogram calculation unit (5) that calculates the histogram value of the region of the given provisional label, assigns a provisional label to the region in the image, and calculates the cumulative X-coordinate value and cumulative Y-coordinate value for each provisional label. After calculating the histogram values in parallel, in parallel with the process of adding a label (updated label) that summarizes the provisional labels of the connected region, the cumulative X coordinate value, cumulative Y coordinate value, and histogram value of these provisional labels are calculated. The X-coordinate cumulative value, Y-coordinate cumulative value, and histogram value of the updated label are calculated from the sum, and the center of gravity is determined from the updated label's X-coordinate cumulative value/histogram value and Y-coordinate cumulative value/histogram value. Features a circuit for calculating the center of gravity of connected regions.