JPH0532711B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an image display device for an underwater detector.
In particular, by displaying fish school images obtained by sequentially changing the depression angle and arranging them in parallel with their positions shifted from each other, the image display makes it easy to understand the three-dimensional distribution of fish schools. Regarding equipment.

<Conventional technology> Normally, schools of fish are often distributed over a certain depth, so when searching for schools of fish using scanning sonar, as shown in Figure 3,
The ultrasonic beam is transmitted while changing the depression angle by a constant angle θ over time. Then, the received signal obtained by receiving the reflected waves from a school of fish under a certain depression angle is temporarily stored in the image memory as image data, and then this image data is transferred from the image memory in synchronization with TV scanning. It is read out and output to a CRT monitor to display images of schools of fish.

<Problems to be solved by the invention> As described above, in the conventional image display device,
The image data obtained based on the transmission and reception of ultrasound beams is transferred directly to the CRT via a single image memory.
Since it is output to a monitor, when the angle of depression changes, the image of the school of fish changes accordingly.

Therefore, when a school of fish is located close to the scanning sonar, the transmission and reception period of the ultrasonic beam is short, so the angle of depression can be changed quickly, and accordingly, the angle of depression can be changed quickly. It is relatively easy to understand the fish school distribution because the image switching cycle is short, but if the fish school is located far away, the transmission and reception period of the ultrasonic beam becomes longer, so the angle of depression also increases. Accordingly, it is necessary to change the image slowly, and as a result, the cycle at which the images of the school of fish are switched becomes longer, for example, at intervals of 10 seconds to 15 seconds. As described above, when the cycle of video switching becomes longer, the relationship between the displayed images before and after switching becomes unclear, making it difficult to understand the fish school distribution three-dimensionally.

The present invention has been made in view of the above circumstances, and is capable of displaying images of a school of fish obtained each time the depression angle is changed in parallel on the same screen by shifting their positions. It is an object of the present invention to make it possible to easily grasp the three-dimensional distribution of fish schools without being affected by the length of the transmission/reception period of an ultrasonic beam.

<Means for Solving the Problems> In order to achieve the above object, the present invention provides a depression angle control circuit that sequentially changes the depression angle of an ultrasonic beam output from a transducer, and a depression angle control circuit that sequentially changes the depression angle of an ultrasonic beam output from a transducer. an image memory that stores the received signal of the ultrasonic beam obtained by the transducer as image data in response to switching of the depression angle by the depression angle control circuit; and a display device that displays the data read out from the image memory. An image display device having the following configuration is adopted.

That is, the image display device of the present invention includes a sub-screen cutting range setting means for setting a specific sub-screen cutting range in which a school of fish etc. is detected from the image displayed on the display, and a sub-screen cutting range setting means for setting a specific sub-screen cutting range in which a school of fish etc. a plurality of sub-screen memories in which image data within the range of depression is stored separately for each depression angle; a memory selection means for sequentially selecting a child screen memory into which image data is to be written; a data output selection means for sequentially selecting and outputting image data for each depression angle read from the child screen memory; and an array display means for arraying and displaying a plurality of selected image data on the same screen of the display along the vertical direction of the screen in the order of change in depression angle.

<Operation> Each time the depression angle of the ultrasonic beam is switched by the depression angle control circuit, the received signal obtained by the transducer is stored as image data in the image memory and then displayed on the display. Also, when looking at the image displayed on the display and setting a specific sub-screen cutting range in which a school of fish etc. has been detected using the sub-screen cutting range setting means, the image data of the set range is saved by the memory selection means. The image data is then written to the selected screen memory in response to switching of the depression angle by the depression angle control circuit. In this way, each time the depression angle is switched, the image data within the set sub-screen cutting range is individually stored in each sub-screen memory.

On the other hand, the image data for each depression angle stored in each child screen memory is read out in synchronization with TV scanning.
Each of the image data is sequentially selected and output by the data output selection means. At this time, the selected image data are arranged and displayed on the same screen of the display device by the array display means along the vertical direction on the screen in the order of change in depression angle.

As a result, by observing the image of the school of fish obtained each time the depression angle is changed, it is possible to easily grasp the three-dimensional distribution of the school of fish without being affected by the length of the transmission/reception period of the ultrasonic beam. be able to.

<Embodiment> FIG. 1 is a block diagram including a scanning sonar image display device. In the figure, reference numeral 1 denotes a transducer, which includes a transducer 2 that transmits and receives an ultrasonic beam, a transmitter 4 that outputs excitation pulses for the transducer 2,
It is composed of a receiving section 6 that amplifies and detects the received signal of the ultrasonic beam obtained by the transducer 2. Also, 8
is a depression angle control circuit that sequentially changes the depression angle of the ultrasonic beam output from the transducer 2 of the transducer 1 over time. 10 is an A/D converter that digitizes the time-series received signal output from the receiving unit 6;
Reference numeral 12 denotes an image memory that stores the A/D-converted received signal of the ultrasonic beam as image data, and 14 writes data to the image memory 12 in response to the input of the transmission trigger pulse from the depression angle control circuit 8. The write address generating section generates the actual address, and includes a coordinate conversion circuit that converts polar coordinates (r, θ) matching the spiral scanning of the received signal to orthogonal coordinates (x, y) matching the TV raster scanning. 1
6 is the image data stored in the image memory 12.
A read address generator 18 generates an address for reading in synchronization with TV scanning, and 18 displays the data read from the image memory 12 as an image.
This is a display device consisting of a CRT color display.

20 is a range setting means for setting a specific sub-screen cutting range (however, the vertical x horizontal dot length is constant) when a school of fish or the like is detected from the image displayed on the display 18. It is a vessel. As shown in FIG. 2, this range setting device 20 specifies the cutting range of the sub-screen by moving the tomographic mark M displayed on the screen to a desired position using a joystick, track ball, etc. not shown. . 22a to 22n are a plurality of child screen memories in which image data within the cropping range set by the range setter 20 are stored separately for each depression angle; 24 is a depression angle switching circuit 8; Memory selection means for selecting a child screen memory into which image data is to be written from among the plurality of child screen memories 22a to 22n in response to the above, and is formed of, for example, a ring counter.

Reference numeral 26 indicates each sub-screen memory 22a to 22 corresponding to the operation of reading image data from the image memory 12.
This is a write address counter that generates a data write address for n, and the address data is selected by the memory selection means 24 via the AND gate 28 only when a high level write range setting signal is output from the range setter 20. is given to the child screen memory. Further, 30 is a read address generation circuit that generates read addresses for image data for each of the child screen memories 22a to 22n.

32 is a switching pulse generator that outputs a switching pulse every time the horizontal synchronization signal is counted a predetermined number of times, and 34 is a downward suppressor that is read out from each sub-screen memory 22a to 22n in synchronization with the switching pulse given from the switching pulse generator 32. A switch 36 serves as a data output selection means for sequentially selecting and outputting image data for each corner; 36 is a switch 32;
This is an array display means that displays the image data selected in 1 on the same screen of the display 18 in an array along the vertical direction on the screen in the order of change in depression angle. In this example, this array display means 36 includes a bit shifter 38 and an adder 4.
0, and each child screen memory 22a
For example, the read address for 22n is 0 to 99 for 22a, and 100 to 199 for 22b.
If the bit shifter 38 sequentially assigns the values 100, 200, etc., each time the switching pulse from the switching pulse generator 32 is applied,
The next stage adder 40 adds the value of the read address from the read address counter 30 to that value.

Reference numeral 40 denotes a frame generation circuit that generates data for displaying an image of a frame F in which parallelograms are connected as shown in FIG. This is a synthesis circuit that synthesizes the respective data and outputs it to the display.

Next, the operation of the above configuration will be explained.

In order to understand the distribution of fish schools, it is necessary to transmit and receive ultrasonic beams while changing the depression angle by a constant angle θ over time. A transmission trigger pulse for generating an ultrasonic beam by switching the depression angle θ at a predetermined cycle taking into consideration the transmission/reception period of the ultrasonic beam is output. This transmission trigger pulse is given to the transmitter 4, the receiver 6, the write address generator 14, and the memory selector 24, respectively.
The transmitting unit 4 outputs an excitation pulse to the transducer 2 in response to this transmission trigger pulse, and the transducer 2 transmits an ultrasonic beam. The echoes of the ultrasonic beam reflected by the school of fish are received by the transducer 2 again, and the time-series received signal from the transducer 2 is amplified and detected by the receiver 6, and then sent to the A/D converter 10. The data is digitized and stored in the image memory 12 as image data. At this time, the write address of the image data is specified by the write address generation section 14.

The image data stored in the image memory 12 under one depression angle is read out by the read address generation section 16 in synchronization with TV scanning, and then sent to the synthesis circuit 4.
2 to the display 18. Display 18
While looking at the image displayed on the screen, move the tomographic mark M using a joy stick, track ball, etc. (not shown) to a specific position where a school of fish, etc. has been detected, and set the cropping range of the sub-screen. Then, the horizontal synchronization signal of the TV is sent from the range setter 20 to the fault mark M.
A high-level write range setting signal is output only during the period corresponding to the cutout range set in . Further, a write address is generated from the write address counter 26 in response to image data being read from the image memory 12, and therefore a high level write range setting signal is output from the range setter 20. The write address is applied to the sub-screen memory selected by the memory selection means 24 via the AND gate 28 only when the memory selection means 24 selects the sub-screen memory. As a result, the image data in the range set by the range setter 20 is written into the small screen memory selected by the memory selection means 24.

In this manner, the memory selection means 24 sequentially selects a predetermined sub-screen memory into which image data is to be written from among the sub-screen memories 22a to 22n in response to the vibration transmission trigger pulse from the depression angle control circuit 8. , each of the child screen memories 22a to 22n individually stores image data within the child screen cutting range set each time the depression angle is switched.

On the other hand, the switching pulse generator 32 outputs a switching pulse every time the horizontal synchronizing signal is counted a predetermined number of times, and this switching pulse is applied to the switch 34 and the bit shifter 38, respectively. The bit shifter 38 outputs each value such as 100, 200, . . . each time the switching pulse from the switching pulse generator 32 is applied.
The adder 40 adds the value from the bit shifter 38 and the value from the read address counter 30, and provides the added value as a read address to each of the small screen memories 22a to 22n. Therefore, the read addresses for each of the child screen memories 22a to 22n are, for example, addresses 0 to 99 in 22a, 22
In b, addresses 100 to 199 are allocated in advance, so when the image data is first read out from the sub-screen memory 22a at addresses 0 to 99 in synchronization with the raster scan of the TV, then Image data is read from the child screen memory 22b at address 199. In this way, each child screen memory 22a to 22n
The image data for each depression angle stored in is read out in accordance with raster scanning of the TV.

Furthermore, since the switch 34 selects the output of each sub-screen memory 22a to 22n in synchronization with the switching pulse given from the switching pulse generator 32, at the same time as data reading from one sub-screen memory 22a is completed, Switcher 3
4 switches the connection and selectively outputs the data to be read from the next sub-screen memory 22b.

In this way, the image data for each depression angle selected by the switch 34 is input to the synthesis circuit 42. The synthesis circuit 42 synthesizes the image data from the image memory 12, the image data from each child screen memory 22a to 22n, and the data for frame generation from the frame generation circuit 40, and generates the image data on the display 1.
Output to 8. As a result, as shown in Figure 2,
For example, on the left side of the screen, images of a school of fish obtained each time the depression angle is changed are displayed as sub-screens, arranged in descending order of depth from top to bottom. For example, if the depression angle is changed sequentially from 22° to 36° in 2° increments, the images of the different schools of fish will be displayed in the order in which the depression angle changes from the top to the bottom. In this display, the distribution status of the fish school along the depth direction is sequentially displayed in parallel, so that the three-dimensional distribution status of the fish school can be intuitively grasped.

In this example, a spiral scan type scanning sonar was explained, but PPI
Of course, the present invention can also be applied to a pencil beam type sonar such as a sonar.

<Effects of the Invention> According to the present invention, images of a school of fish obtained each time the depression angle is changed are displayed in an array along the vertical direction on the screen in the order of change in the depression angle on the same screen.
Excellent effects such as the ability to easily grasp the distribution of fish schools in the depth direction are achieved without being affected by the length of the transmission/reception period of the ultrasonic beam.

[Brief explanation of drawings]

1 and 2 show embodiments of the invention,
Fig. 1 is a block diagram including a scanning sonar image display device, Fig. 2 is an explanatory diagram showing an example in which images obtained by changing the depression angle over time are arranged and displayed in parallel at shifted positions; FIG. 3 is an explanatory diagram when the fish school distribution is investigated by changing the depression angle. 1... Transducer/receiver, 8... Depression angle control circuit, 12
...Image memory, 18...Display device, 20...Sub screen cutting range setting means (range setting device), 22a
~22n...Small screen memory, 24...Memory selection means, 34...Data output selection means (switcher), 36...Array display means.

Claims (1)

[Scope of Claims] 1. A depression angle control circuit that sequentially changes the elevation angle of an ultrasonic beam output from a transducer, and a depression angle control circuit that changes the elevation angle of the ultrasonic beam output from the transducer in response to switching of the depression angle by the depression angle control circuit. An image display device comprising an image memory that stores received signals of ultrasound beams obtained as image data, and a display that displays data read from the image memory, the image displayed on the display. a sub-screen cropping range setting means for setting a specific sub-screen cropping range in which a school of fish, etc. is detected; and image data within the range set by this sub-screen cropping range setting means is stored separately for each depression angle. a plurality of child screen memories to which image data is to be written from among the plurality of child screen memories in response to switching of the depression angle by the depression angle suppression circuit; data output selection means for sequentially selecting and outputting image data for each depression angle read from the child screen memory; and data output selection means for sequentially selecting and outputting image data for each depression angle read from the child screen memory; and displaying a plurality of image data selected by the data output selection means on the same screen of the display device. An image display device for an underwater detector, comprising: array display means for displaying an array along the vertical direction of the screen in the order of changes in the angle of depression;