JPH05671B2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a display device that displays an image of a detection signal obtained by an underwater detector, and particularly relates to a display device that displays an image of a detection signal obtained by an underwater detector. Alternatively, the present invention relates to a display device suitable for understanding changes in fish shadows, etc.

<Prior art> In general, observing the movement direction of fish schools detected by underwater detectors such as scanning sonar and fish finders and changes in fish shadows provides important information when searching for fish schools or determining the situation when casting a net. becomes.

Conventionally, when observing the movement direction of a school of fish or changes in fish shadows, a mark is displayed at the absolute position of the school of fish at a certain point in time, and the method is used to observe how the school of fish moves relative to the fixed mark. Alternatively, the current screen showing the current position of the school of fish and the past screen based on the data in the storage device showing the position of the past school of fish may be alternately displayed.
The current screen being displayed is compared with past screens that the observer remembers.

<Problems to be Solved by the Invention> However, with such conventional displays, it is difficult to accurately grasp the moving direction of fish schools and changes in fish shadows.

In other words, when observing the moving direction of a school of fish by attaching marks, it is not possible to observe changes in fish shadows, and when observing by alternating between the current screen and the past screen. , the switching operation is troublesome, and furthermore, accurate observation is difficult when relying on the observer's memory.

The present invention has been made in view of the above-mentioned points, and an object of the present invention is to provide a display device for an underwater detector that makes it easy to accurately grasp the moving direction of fish schools and changes in fish shadows. .

<Means for solving the problems> In order to achieve the above-mentioned object, the present invention has the following features:
A display device for an underwater detector that writes a detection signal for a screen into a video memory, reads it from the video memory, and displays a detection image on a display,
a detection range setting means for setting a desired detection range from the detection image displayed on the display; a small screen memory in which a detection signal corresponding to the detection range is written or read; display area setting means for setting a predetermined display area for displaying an image based on the detection signal on the display as a small screen; and an intensity of the detection signal read from the small screen memory when updating data in the small screen memory. Arithmetic means for lowering the level by a predetermined level and comparing the intensity level of this detection signal with the intensity level of the latest detection signal at the same position read from the video memory for each pixel, and outputting a detection signal of a high level. Based on the output of the detection range setting means, a detection signal corresponding to the detection range outputted from the calculation means is written to the small screen memory to update data in the small screen memory, and the display area setting is performed. small screen memory control means for reading a detection signal from a small screen memory corresponding to the predetermined display area based on an output of the means; and a detection signal read from the video memory and from the small screen memory for the predetermined display area. a detection signal read out correspondingly to the detection signal and outputting the synthesized signal to the display; is displayed as a small screen.

<Operation> According to the above configuration, the detection signal corresponding to the detection range that is part of the detection image is written in the small screen memory, but at that time, the previous detection signal that has already been written in the small screen memory is The signal intensity level is lowered and compared with the intensity level of the latest detection signal at the same location read out from the video memory, and the detection signal with the higher intensity level is written, so the small screen memory contains the past detection signals. and the current detection signal will be written with different intensity levels. Therefore, by reading out the detection signal from this small screen memory and displaying it on a part of the display, changes from the past to the present can be seen. An image showing the status will be displayed on a small screen.

<Example> Hereinafter, an example of the present invention will be described in detail with reference to the drawings. FIG. 1 is a block diagram of one embodiment of the present invention.

In the figure, 1 is a video memory that stores one screen worth of detection signals obtained by the underwater detector, 2 is a read address generation circuit that generates a read address for reading out the detection signals from the video memory 1, and 3 is a detection signal. A display 4 displays a detection image in a hue corresponding to the intensity level of the signal, and 4 is a scanning circuit.

In this embodiment, a detection image showing the current state based on the latest detection signal from the video memory 1 and an image showing changes in the state from the past to the present in a certain detection range are superimposed and displayed. It is configured as follows.

That is, the display device of this embodiment has the display device 3
detection range setting means 5 for setting a desired detection range from the detection image from the video memory 1 displayed on the screen;
, a small screen memory 6 into which a detection signal corresponding to this detection range is written or read, and a predetermined display area where an image based on the detection signal read out from this small screen memory 6 is displayed on the display 3 as a small screen. and a display area setting means 7 for setting the intensity level of the detection signal by lowering the intensity level of the detection signal read from the small screen memory 6 by a predetermined level when updating the data in the small screen memory 6. a calculation means 8 that compares the intensity level of the latest detection signal at the same position read from the video memory 1 for each pixel and outputs a detection signal with a high level;
Based on the output of the detection range setting means 5, a detection signal corresponding to the detection range outputted from the calculation means 8 is written into the small screen memory 6 to update the data in the small screen memory 6, and the display A small screen memory control means 9 reads out detection signals from the small screen memory 6 corresponding to a predetermined display area based on the output of the area setting means 7; It is provided with a synthesizing means 10 for synthesizing detection signals read out corresponding to a predetermined display area and outputting the synthesized signal to the display 3.

The detection range setting means 5 sets a desired reaction detection range in which a school of fish has responded from the detection image read out from the video memory 1 and displayed on the display 3, using a marker or the like. The setting means 5 receives data from the speedometer and the gyro compass in order to display the absolute position after subtracting the movement of the own ship. This detection range setting means 5
The detection range set by , for example, corresponds to part A of the area A of the video memory 1 as shown in FIG. When the data is read out, a corresponding output is given to the small screen memory control means 9. Changes in this detection range are displayed on the display 3 as a small screen as described later.

Of the detection signals output from the calculation means 8 when updating data, the detection signal corresponding to the detection range is written in the small screen memory 6, and the data is updated. It is read out and output to the synthesis circuit 10 and displayed as a small screen.

The display area setting means 7 sets the display area of the small screen on the display 3, and in this embodiment, as shown in FIG. That's what I do.

The calculation means 8 performs a predetermined calculation process when updating the data in the small screen memory 6 for each vibration transmission, and increases the intensity level of the detection signal read from the small screen memory 6 to 1. A subtractor 11 that lowers the level, and a comparison circuit that compares the intensity level of the detection signal from the subtracter 11 with the latest detection signal at the same position from the video memory 1 and outputs a detection signal with a high intensity level. 12, and performs calculations and outputs for each pixel.

Through the calculation process of the calculation means 8, past data and the latest current data are written at different levels into the small screen memory 6 for each transmission. , this small screen memory 6
By reading the data corresponding to a predetermined display area, changes in fish schools and fish shadows from the past to the present in the detection range can be displayed on a small screen.

The small screen memory control means 9 that controls writing and reading of the small screen memory 6 is supplied with a transmission synchronization signal synchronized with the transmission trigger and horizontal and vertical synchronization signals, as well as the output of the detection range setting means 5. An update gate circuit 13, an update address generation circuit 14 that generates an update address in response to the output of the update gate circuit 13, and a read address generated based on the output of the display area setting means 7. Read address generation circuit 15
, a first switch circuit 16 that switches addresses in response to the output of the update gate circuit 13, and a second switch circuit 17 that switches between writing and reading in response to the output of the update gate circuit 13.

The update gate circuit 13 performs one transmission for each transmission.
A signal for writing the detection range data of the screen's worth of data into the small screen memory 6 and updating the data is output.

The small screen memory 6 is updated by the small screen memory control means 9 once for each vibration transmission.
During a period other than this update period, that is, during a period when no update signal is output from the update gate circuit 13, the first switch circuit 16 supplies the read address from the read address generation circuit 15 to the small screen memory 6. At the same time, the second switch circuit 17 provides a low level output corresponding to reading to the small screen memory 6. Therefore, during periods other than the update period, detection signals are read out from the small screen memory 6 in accordance with the display area of the small screen, and are output to the synthesis circuit 10 and displayed.

During the update period, the output of the update gate circuit 13 causes the first and second switch circuits 14, 1
7 is switched, an update address is generated, the detection signal from the small screen memory 6 is read out and given to the calculation means 8, and the detection signal from the calculation means 8 is written. During this update period, the 70 ns clock pulse from the clock pulse generation circuit 18 is multiplied and given to the second switch circuit 17 as a 35 ns clock pulse.
It is read during the high level period of the clock pulse, and written during the low level period of the clock pulse. The detection signal for updating read out from the small screen memory 6 during this update period is not output to the synthesis circuit 10 by the switch 20.

Next, the display operation of the above embodiment will be explained based on FIGS. 4 and 5.

4A to 4E schematically show changes in the detection range (range indicated by A in FIG. 2) of the detection image based on the detection signal of the video memory 1 over time. There is. That is, in this FIG. 4, the entire detected image displayed on the large screen in an area other than the predetermined area B in FIG. 3 is not shown, but only the image of the detection range that is a part of the detected image It shows.

5A to 5E are images of a small screen (a screen displayed in a predetermined area B in FIG. 3) based on the detection signal of the small screen memory 6 in which the detection signal of the detection range is updated and stored. This diagram schematically shows the changes in over time.

In both figures, A → E corresponds to the passage of time, and the numerical values are the strength level of the detection signal,
Therefore, it corresponds to the hue of the display.

As shown in FIGS. 4A to 4E, the latest images of the detection range based on the detection signals in the video memory 1 are displayed one after another for each vibration transmission. In this embodiment, intensity levels 8 and 10 are displayed, and this display is the same as the conventional one.

On the other hand, in the small screen memory 6, a detection signal with a higher level is updated by lowering the intensity level of the previous detection signal by 1 and comparing the intensity level of this detection signal with the latest intensity level of the video memory 1 for each pixel. At the same time, the detection signal in the small screen memory 6 is read out and displayed as a small screen in a predetermined area B, so that the previous display is also lowered in level, as shown in FIGS. 5A to 5E. The latest data with a high intensity level will also be displayed.

That is, the initial state shown in FIG. 5A is the same as in FIG. 4, but after the next transmission,
As shown in FIG. 5B, the previous data is displayed one level lower. That is, intensity levels 10 and 8 in FIG. 5A become intensity levels 9 and 7 in FIG. 5B.
Furthermore, new data are also displayed as intensity levels 10 and 8 in FIG. Thereafter, the images are displayed sequentially as time passes, as shown in FIG. 5 from C to E.

Therefore, the small screen displayed in a predetermined area B in FIG. 3 displays the movement direction of the fish school and changes in fish shadows from the past to the present in the detection range set by the detection range setting means 5. That will happen.

Furthermore, in areas other than the predetermined area B, the detected image is displayed on a large screen as in the past.

In this way, the small screen displays data from the past to the present in the detection range at different levels.
What's more, past data is displayed at progressively lower levels, so for example,
You can accurately grasp the moving direction of fish schools and changes in fish shadows at a glance.

FIG. 6 is a diagram schematically showing changes in images on a small screen corresponding to FIG. 5 showing another display example of the present invention. In this display, only detected signals with a strength level of 10 are displayed. The other configurations are the same as those in the above embodiment.

Note that the display device of the present invention can also perform a conventional display based only on the detection signal from the video memory 1 without displaying a small screen.

<Effects of the Invention> As described above, according to the present invention, when writing a detection signal corresponding to a desired detection range into a small screen memory, the previous contents of the small screen memory and the latest data are written at the same position. The data is processed and written, and the data in this small screen memory is read out and displayed as a small screen in a predetermined area of the display, so this small screen displays the state of change from the past to the present. Compared to the conventional example, it becomes easier to accurately grasp, for example, the moving direction of a school of fish and changes in fish shadows.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of one embodiment of the present invention, and FIG.
The figure shows the area of the video memory corresponding to the detection range, Figure 3 shows the display area of the small screen, and Figure 4 shows the area of the video memory corresponding to the detection range.
The figure is a diagram schematically showing changes in an image based on a detection signal from a video memory, Figure 5 is a diagram schematically showing a change in an image based on a detection signal from a small screen memory, and Figure 6 is a diagram schematically showing changes in an image based on a detection signal from a small screen memory. FIG. 6 is a diagram schematically showing a change in an image based on a detection signal from a small screen memory in a display. DESCRIPTION OF SYMBOLS 1...Video memory, 3...Display device, 5...Detection range setting means, 6...Small screen memory, 7...Display area setting means, 8...Calculating means, 9...Small screen memory control means, 10...Composition means.

Claims (1)

[Scope of Claims] 1. A display device for an underwater detector that writes detection signals for one screen into a video memory, reads them out from the video memory, and displays detected images on a display, comprising: a detection range setting means for setting a desired detection range from the detection image; a small screen memory into which a detection signal corresponding to the detection range is written or read; display area setting means for setting a predetermined display area to be displayed on the display as a screen; The strength level of the detection signal,
computing means for comparing the intensity level of the latest detection signal at the same position read from the video memory for each pixel and outputting a detection signal of a high level; and based on the output of the detection range setting means, A detection signal corresponding to the detection range output from the calculation means is written into the small screen memory to update data in the small screen memory, and a detection signal in the small screen memory is updated based on the output of the display area setting means. a small screen memory control means for reading data corresponding to the predetermined display area; and displaying a composite of a detection signal read from the video memory and a detection signal read from the small screen memory corresponding to the predetermined display area. an underwater detector for displaying an image of the detection range based on the detection signal in the small screen memory as a small screen on a part of the detection image based on the detection signal in the video memory. display device.