JPH03251780A - Front image display method of ultrasonic underwater imaging apparatus - Google Patents

Abstract

PURPOSE:To accurately discriminate the distance of objective matter according to a color by forming mixed color data by setting receiving intensity and a distance to parameters. CONSTITUTION:The receiving data S2 obtained by converting the ultrasonic reflected wave from objective matter to an electric signal is stored in a receiving data memory 11 and a signal processor 10 calculates a dip 10a, an azimuth 10b and a distance 10c with respect to the objective matter. A beam forming operation circuit 12 performs the beam forming operation of the receiving data S2 to calculate receiving intensity 12a and this receiving intensity 12 and the distance 10c are used as parameters to form mixed color data and a front image is colored by this mixed color data to be displayed on a CRT 1. Therefore, even when the reflectivity of an ultrasonic wave is different according to the objective matter, the difference of reflectivity is corrected on the basis of a distance to make it possible to properly discriminate a distance.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is an ultrasonic underwater device that irradiates a target object with ultrasonic waves, receives the reflected waves, and displays a front image of the target object on a display. Front view ff1 of the imaging device (hereinafter referred to as C mode image)
The present invention relates to a display method, and particularly to a C-mode image display method that allows identification by color in the depth (distance) direction.

(Conventional technology) Conventionally, technologies in this field include Oki Electric Research and Development,
53-4 [132] (Sho 6l-10) Nitori and Igarashi, “Digital signal processing technology in underwater acoustics JP,
There were those described in 53-58.

Conventionally, as described in the above-mentioned literature, an ultrasonic underwater imaging device uses a cathode ray tube (hereinafter referred to as CRT) to transmit a C-mode image, which is an image on a plane perpendicular to the propagation direction of sound waves, that is, the range direction, similar to optical imaging. ).

The display of a C-mode image on a CRT is configured with the vertical direction of the CRT as the depression angle (height) and the horizontal direction as the azimuth (width). is displayed. Change this display image to the second
As shown in the figure.

In FIG. 2, when there is a close target object 2a and a far target object 2b within the measurement target area IA displayed on the CRTI, both the target objects 2a and 2b are CR
It is displayed as a C mode image on the TI screen.

In this display, the received wave intensity can be calculated by performing arithmetic operations on dots within the CRTI to determine the angle of depression, azimuth, and distance of the points, and then performing beamforming calculations for the points. In order to display the received wave intensity information in the depth direction (distance direction) on the screen of the CRTI in terms of brightness, among the parameters of depression angle, azimuth, and distance, the distance must be set in the depth direction from the starting end 3a of the measurement target area IA. By increasing the received wave intensity to the terminal end 3b and accumulating the received wave intensity obtained by beamforming calculation in the depth direction and displaying the accumulation result, it becomes possible to display the distance by brightness.

FIG. 3 is a block diagram showing an example of the configuration of an image forming section in a conventional ultrasonic underwater imaging device, and a conventional C-mode image display method will be described with reference to this diagram.

The image forming unit in FIG. 3 starts its operation in response to an operation instruction S1 from a higher-level central processing unit (hereinafter referred to as CPtJ), and performs signal processing to output an angle of depression 10a, an azimuth 10b, a distance 10c, and a division instruction 10d. a processor 10, a received wave data storage memory 11 that stores received wave data S2,
A beamforming calculation circuit 12 that performs beamforming calculations based on the outputs of the signal processing processor 10 and the memory 11 and outputs a received wave intensity 12a, and a video data storage memory 13 that stores the depression angle 10a, azimuth 10b, etc.
and an arithmetic unit 1 that performs addition of received wave intensity 12a and division according to division instruction 10d, and outputs data 14a to memory 13.
4, a display circuit 15, and a CRTI.

In FIG. 3, ultrasonic waves are irradiated from a transmitter (not shown) to, for example, the target objects 2a and 2b in FIG. 2, and the reflected waves are converted into received electrical signal data S2 by a receiver array (not shown). , stores the received wave data S2 in the memory 11.

The signal processor 10 starts its operation in response to an operation instruction S1 from the host CPU, calculates the depression angle 10a, the azimuth 10b, and the distance 10c for all the dots on the CRTI, and
Beamforming calculator! #I12 to instruct calculation execution. The beamforming calculation circuit 12 is
A beamforming calculation is performed on the data from the memory 11 to obtain the received wave intensity 12a, and the received wave intensity 12a is
is output to the arithmetic unit 14. The signal processing processor 10 is
Using the angle of depression 10a and the direction 10b as addresses, the arithmetic unit 1
The output data 14a of No. 4 is stored in the memory 13.

Next, the beamforming calculation circuit 12 increases only the distance 10c in the depth direction based on the same depression angle 10a and azimuth 10b, and performs the beamforming calculation again.
The received wave intensity 12a, which is the calculation result, is given to the calculation unit 14. The arithmetic unit 14 reads the previous data stored in the memory 13, and adds the previous data and the input received wave intensity 12a. The data 14a that is the result of this addition is stored in the memory 13 again using the depression angle 10a and the azimuth Job as addresses. Such processing is repeated from the starting end 3a to the ending end 3b of the measurement range shown in FIG. i&
Later, in response to the # calculation instruction 10d from the signal processing processor 10, the arithmetic unit 4 calculates the result of dividing the addition result by the number of additions (that is, the average (fl>) of the received wave intensity 12a in the measurement range, and stores it in the memory 13. As a result, as shown in FIG. 2, the target object 2a, whose received wave intensity is expressed in the form of luminance, is displayed on the screen of the CRTI.
A C mode image of 2b is displayed.

(Problem M to be Solved by the Invention) However, the conventional C-mode image display method has the following problems.

The conventional C-mode image display method is a method of visualizing the reflected intensity from the target objects 2a and 2b, that is, the received wave intensity, in the form of brightness using ultrasonic waves. However, since the ultrasonic underwater imaging device is used underwater, it is not possible to confirm the object to be measured in advance, so the measurement range, that is, the measurement range, is often widened.

In this case, even if it is found that the image object displayed on the CRTI is within the measurement range, since the measurement range is wide, the difference in brightness will be small and the target object 2a
, 2b is located within the measurement range. Further, the reflectance of the ultrasonic waves to the target objects 2a, 2b differs depending on the material of the target objects 2a, 2b.

Therefore, just because the received wave intensity is strong does not necessarily mean that it is close. Therefore, with the conventional display method, it has been impossible to appropriately identify the distance between the target objects 2a and 2b from the video screen of the CRTl.

The present invention provides a C-mode image display method for an ultrasonic underwater imaging device that solves the problem of the prior art, which is that it is difficult to distinguish the distance of a target object from the image screen of a display device.

(Means for Solving the Problems) In order to solve the above problems, the present invention inputs reception data obtained by converting ultrasonic reflected waves from a target object into electrical signals,
Based on the angle of depression, azimuth, and distance calculated for the target object, the received wave data is subjected to Beano and Formink calculations to obtain the received wave intensity, and the vertical direction is the depression angle, the horizontal direction is the azimuth, and the depth direction is calculated. A C-mode image display method for an ultrasonic underwater imaging device for displaying a C-mode image of the target object on a display with the distance as the distance, M includes the following means. That is, in the present invention, the received wave intensity obtained by the beamforming calculation and the calculated distance are used as parameters to generate mixed color data within the measurement range according to the parameters, and the C mode image is generated using the mixed color data. The information is colored and displayed on the display.

(Function) According to the present invention, the C of the ultrasonic underwater imaging device is as described above.
Since the mode image display method has been configured, it is possible to generate mixed color data corresponding to the received wave intensity and distance as parameters, even if the ultrasonic reflectance differs depending on the target object.
The difference in reflectance is corrected based on the distance, and mixed color data without any adverse effects due to the difference in reflectance is obtained. Then, by coloring the video screen in the distance direction using the mixed color data, the video screen can be divided into appropriate distances MH. Therefore, the above problem can be solved.

(Embodiment) FIG. 1 is a block diagram of an image forming section in an ultrasonic underwater imaging device showing an embodiment of the present invention. Elements common to the conventional elements in FIG. has been done.

In this image forming section, three R, G
, B (red, green, blue) conversion ROMs (read only memories) 20-1 to 20-3 are connected, and further the R, G, B conversion ROMs 20 to 1 to 20-3 and the signal processing processor 10 are connected. Three arithmetic units 14-1 to 14-3 for addition and division are connected to the output side.゛Furthermore,
Three video data storage memories 13-1 to 13-3 are connected to the output sides of the computing units 14-1 to 14-3.
The outputs (iljl) of the memories 13-1 to 13-3 are connected to the CRTI via the display circuit 15, and are also feedback-connected to the arithmetic units 14-1 to 14-3.

Here, R conversion ROM20-1, G conversion ROM20-2
and B conversion ROM 20-3 respectively store color data of density corresponding to distance n and received wave intensity m, and receive wave intensity 12 outputted from the beamforming calculator 812.
a, and the distance 1 output from the signal processing processor 10
It is accessed using 0c as an address. And each R,G
, B conversion ROMs 20-1 to 20-3 are output to computing units 14-1 to 14-3, respectively. Arithmetic units 14-1 to 14-3 each have R, G, and B
The color data of each of the conversion ROMs 20-1 to 20-3 is added to the output of the video data storage memories 13-1 to 13-3 to accumulate the color data over the measurement range, and the division instruction from the signal processing processor 10 is It has a function of dividing the number of additions by 10d and outputting average color data 14A in the measurement range to the video data storage memories 13-1 to 13-3, respectively. Further, the video data storage memories 13-1 to 13-3 store output data 14A of the arithmetic units 14-1 to 14-3 using the depression angle 10a and azimuth 10b output from the signal processing processor 10 as addresses, It has a function of providing the read data to the computing units 14-1 to 14-3 and the display circuit 15.

FIG. 4 shows the R, G, B conversion ROM 20- in FIG.
It is a figure showing the contents of 1 to 20-3.

The color combination of the R, G, B conversion ROMs 20-1 to 20-3 is set as follows.

In other words, for example, short distance is R (red) and medium distance is G (green).
, when long distance is expressed by B (blue), the B component is not required for a color change from R to G, and the R component is not required for a color change from G to B for the same reason. Therefore, each color data is stored in the R, G, and B conversion ROMs 20-1 to 20-2 so that only the mixing of R and G and the mixing of G and B are performed, respectively.
It is stored in 0-3. With this combination, when color data is accumulated in the depth (distance) direction in C mode image display, the three colors R, G, and B are mixed and R→
There is no fear that the G-B color transition will not be performed smoothly. In other words, if there is an object nearby and there is an ultrasonic reflection from it, the ultrasonic wave cannot travel behind it, so there will be no ultrasonic reflection from further distances. Therefore, even if the composition is as shown in Figure 4, R, G
, H does not mix.

Next, the C-mode image display method of this embodiment will be explained with reference to FIGS. 1 and 4.

The reflected wave from the target object is converted into received electric signal data S2 by a receiver array (not shown), and the received wave data S2
is stored in the received wave data storage memory 11. The signal processor 10 starts its operation in response to an operation instruction S1 from a host CPU, for example, and calculates an angle of depression 10a, an azimuth 10b, and a distance 10c for all dots of the CRTI, and provides them to the beamforming calculation circuit 12 for calculation. At the same time as instructing the execution, the distance 10c is stored in the R, G, B conversion ROM2.
0-1 to 20-3 respectively.

The beamforming calculation circuit 12 performs beamforming calculation on the data from the received wave data storage memory 11, obtains the received wave intensity 12a, and performs R, G, B conversion RO.
Give to each of M20-1 to 20-3. The R, G, B conversion ROMs 20-1 to 20-3 have received wave intensity of 12a x distance of 1
It is accessed using 10c as an address. The received wave intensity is m
, when the distance is n, R, G, B conversion ROM 20-1 to 2
The outputs of 0-3 become color data Rm, Gm, and Bm, respectively. In the case of the combination shown in FIG. 4, the color data output from the RlG, B conversion ROMs 20-1 to 20-3 are as follows:
Rm+Gm, and when the color data is mixed, an intermediate color between R and G is obtained.

The color data Rm, Gm, and Bm output from the R, G, and B conversion ROMs 20-1 to 20-3 are processed by the arithmetic units 14-1 to 14.
−3 respectively. These computing units 14-1 to 14
-3 each output data 14A is transmitted to the signal processing processor 10.
The depression angle 10a and the azimuth 10b outputted from are stored as addresses in the video data storage memories 13-1 to 13-3, respectively, and each data in the memories 13-1 to 13-3 is sent to the computing units 14-1 to 14-. Output to 3. Arithmetic unit 1
4-1 to 14-3 are R, G, B conversion ROM 20-1.
~20-3 output data and video data storage memory 13
The previous data stored in -1 to 13-3 are added, and data 14A, which is the result of the addition, is added to the video data storage memory 13 with the depression angle 10a and the azimuth 10b as addresses.
-1-133.

The arithmetic units 14-1 to 14-3 repeatedly perform such addition processing from the start end 3a to the end end 3b of the measurement range shown in FIG. Divide the result by the number of additions,
Each color data, which is the result of the division, is provided to the display circuit 15 via the video data storage memories 13-1 to 13-3. Then, the display circuit 15 displays, on the screen of the CRTl, an image of the target object colored in the depth (distance W, . . . ) direction using mixed color data obtained by mixing each color.

As described above, in this embodiment, the C-mode image of the target object is colored and displayed in the depth (distance) direction using colors according to the distance to the target object. Identification becomes possible, which has the following advantages:

(a) The color display allows accurate determination of the distance of the target object.

(b) When the target object moves in the distance direction, the movement condition is displayed as a change in color, so that the movement of the target object in the distance direction can be accurately determined.

(C) When the ultrasonic underwater imaging device shown in FIG. 1 to which the C-mode image display method of this embodiment is applied is attached to a moving object such as a submarine and used for detecting obstacles and navigation, it is possible to avoid danger. can be done quickly and accurately.

(d) R, G, B conversion ROM 2 as shown in Figure 4
By simply changing the contents of 0-1 to 20-3, it can be easily and quickly changed for other color lights.

In addition, changes by color light can be made using the R, G, B conversion ROM20-1.
Since it is sufficient to simply replace 20-3 with another ROM, it is highly economical.

Note that the present invention is not limited to the illustrated embodiment, and the method for generating mixed color data and the means for displaying the mixed color data can be implemented using various circuits. Examples of circuit modifications include the following.

(j) R, G, B conversion ROM 20-1 to 2 in Fig. 1
Each of the ROMs 0-3 is composed of independent ROMs, but these are divided into two ROMs 11 and 3 areas for storing color data are provided in each ROM, and color data is stored in each area. It is also possible to store h each. Also,
The R, G, and B conversion ROMs 20-1 to 20-3 may be configured with readable/writable memories, thereby making it possible to change the contents of the memories to different colors simply by rewriting the contents of the memories.

(ii) Three arithmetic units 14-1 to 14-3 in FIG.
They may be configured with one arithmetic unit, or the arithmetic functions of the arithmetic units 14-1 to 14-3 may be executed by program processing.

(iii) The three video data storage memories 13-1 to 13-3 in FIG. 1 are configured as one memory, and each memory has an area for storing data for each color. Even if it is provided, the same functions and effects as in FIG. 1 can be obtained.

(1v) The CRTI shown in FIG. 1 may be configured with another display such as a liquid crystal display capable of color display.

(Effects of the Invention) As described above in detail, according to the present invention, the C-mode image is displayed on the display by coloring the distance direction with a color corresponding to the received wave intensity and distance as parameters. Therefore, even if the reflectance of ultrasound waves differs depending on the target object,
Images can be displayed on the display in accurate colors that correspond to the distance to the target object. Therefore, the distance* of the image can be easily and accurately identified by color. Therefore, effects such as being able to determine whether the target object is far or near or whether the target object is moving in the distance direction can be expected.

[Brief explanation of drawings]

FIG. 1 shows an embodiment of the present invention, and is a block diagram of an image forming unit in an ultrasonic underwater imaging device for explaining the C-mode image display method. FIG. 2 is a diagram showing a display image of a target object. FIG. 3 is a block diagram of an image forming section in an ultrasonic underwater imaging device for explaining a conventional C-mode image display method, and FIG. 4 is a diagram showing the contents of the R, G, B conversion ROM in FIG. 1. . 1...CRT, 10...Signal processing processor, 10a...Angle of depression, 10b...
Direction, 10c...distance, 10d...division instruction, 11...memory for storing received wave data, 1
2...Beamforming calculation circuit, 12a.
...Received wave intensity, 13-1 to 13-3...
Video data storage memory, 14-1 to 14-3...
...Arithmetic unit, 15...Display circuit, 20-1 to 2
03...R, G, B conversion ROM, Sl...
...Operation instruction, S2...Received wave data.

Claims (1)

[Claims] An angle of depression calculated for the target object by inputting reception data obtained by converting ultrasonic reflected waves from the target object into electrical signals,
Based on the azimuth and distance, a beamforming calculation is performed on the received wave data to determine the received wave intensity, and a front image of the target object is displayed on a display with the vertical direction as the depression angle, the horizontal direction as the azimuth, and the depth direction as the distance. In the method for displaying a front image of an ultrasonic underwater imaging device, the received wave intensity obtained by the beamforming calculation and the calculated distance are used as parameters to generate mixed color data within a measurement range corresponding to the received wave intensity and the calculated distance, and the mixed color data is A front image display method for an ultrasonic underwater imaging device, characterized in that the front image is colored using color data and displayed on the display.