JP2606565B2 - Display device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a display device for displaying a video signal obtained from a radar or a sonar on a monitor together with graphic data.

[0002]

2. Description of the Related Art A display device which processes a radar video signal or the like into several forms according to an operator's selection and displays it on a screen has been put to practical use.

FIG. 2 is a block diagram showing an example of a conventional display device. In FIG. 1, a CPU 101 generates cursor information and graphic data corresponding to an instruction from an operator. The cursor generator 102 generates cursor symbol data based on the cursor information, and the graphic data is stored in the graphic data frame memory 103. The video frame memory 104 stores image data obtained by digitally converting a video signal obtained by a radar or a sonar.

A look-up table memory 105 receives cursor symbol data, graphic data, and image data from the video frame memory 104 to generate a color signal for monitor display.
The signal is converted into an analog signal by the / A converter 106 and displayed on the screen by the monitor 107. The screen displayed by the monitor 107 is, for example, radar video mixed with graphic data such as terrain and symbol display, and further displayed by a cursor.

[0005]

SUMMARY OF THE INVENTION Such a monitor 10
On the display screen 7, the operator may visually compare the brightness of several bright spots and read necessary information. However, in the conventional display device, since the level of the luminance is visually determined, the determination may vary.

In a conventional display device, if a luminance level at a position designated by an operator is to be displayed on a monitor screen, a video signal is written into a video frame memory 104 and a look-up table memory 1 is used.
It is necessary to stop the read operation to read out the pixel data 05 and read out the pixel data for detecting the luminance level. For this,
Temporal continuity of the video signal is impaired, resulting in a problem that information becomes unstable in time and reliability of screen display is reduced.

An object of the present invention is to provide a display device capable of displaying a luminance level on a monitor without deteriorating the reliability of a screen display of radar video or sonar video.

[0008]

A display device according to the present invention displays a video signal obtained from a radar or a sonar on a monitor together with graphic data on a monitor.
An image memory capable of storing the video signal as digital image data; and data for extracting image data corresponding to a designated cursor position among image data read out from the image memory for the monitor display. Extracting means; luminance level detecting means for detecting a luminance level of the image data extracted by the data extracting means; and graphic data generation for inserting luminance data for displaying the detected luminance level on a screen into the graphic data. And means.

[0009]

The data extracting means extracts the image data corresponding to the designated cursor position from the image data read from the image memory for monitor display. Luminance level detection is performed using the extracted data, and the luminance level is graphically displayed. At this time, the image data read from the video image memory is displayed on the monitor as usual.

[0010]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a block diagram showing one embodiment of a display device according to the present invention. In FIG. 1, a CPU 1 includes necessary ROM and RAM, and generates cursor information (cursor position, cursor display form, etc.) and graphic data (symbols, numerical values, predetermined figures, etc.) corresponding to an operator's instruction. At the same time, the operation of the entire circuit constituting this embodiment is controlled.

The cursor generator 2 generates cursor symbol data according to cursor information from the CPU 1. The graphic data frame memory 3 includes a CPU
1 is stored for one frame (or one field), and the video frame memory 4 stores image data obtained by digitally converting a video signal obtained by a radar or a sonar for one frame (or one field). Minutes) to store.

The lookup table memory 5 stores color information for color display, and includes cursor symbol data from the cursor generator 2, graphic data from the graphic data frame memory 3, and video data from the video frame memory 4. Are input, and a color signal in a state where each data is combined is generated. At this time, the graphic data frame memory 3
The read operation between the data and the video frame memory 4 is performed synchronously, and each read data is serially input to the look-up table memory 5.

The data output from the look-up table memory 5 is converted into an analog signal by a D / A converter 6 and is input to a monitor 7 as an analog video signal to be displayed on a screen.

The cursor symbol data output from the cursor generator 2 and the image data read from the video frame memory 4 are input to a data extraction unit, and the image data at the designated cursor position is extracted.

The data extracting section comprises a cursor position detecting circuit 8 for inputting cursor symbol data and a data register 9 for inputting read image data. The cursor position detection circuit 8 outputs a position detection signal corresponding to the cursor position to the data register 9 as a write signal when the operator specifies the cursor position and instructs to detect the luminance level. That is, the data register 9
Captures only pixel data according to the position detection timing of the cursor position detection circuit 8 from the image data sequentially read from the video frame memory 4 and outputs the pixel data to the luminance level detection unit 10.

The luminance level detecting section 10 has a level division set in advance, and receives luminance data of the pixel data stored in the data register 9 to determine the luminance level. The luminance level at the cursor position thus obtained is C
Graphic data that is output to the PU 1 and includes data for displaying the luminance level is generated and stored in the graphic data frame memory 3. Note that the luminance level detection unit 10 can be configured as an independent circuit, but can also be incorporated in the CPU 1 as software.

Next, a specific operation of this embodiment having the above-described configuration will be described.

The graphic data sequentially read from the graphic data frame memory 3 and the image data sequentially read from the video frame memory 4 are combined with the cursor symbol data sequentially output from the cursor generator 2 and look-up table memories 5 and D.
It is assumed that the screen is displayed on the monitor 7 via the / A converter 6.

Here, the operator designates the cursor position using an input device (not shown) such as a keyboard, and gives an instruction to display a luminance level. Thus, the cursor position detection circuit 8 receives the cursor symbol data from the cursor generator 2 to detect the designated cursor position, and outputs a write signal to the data register 9 at the timing of the designated position. Therefore, the data register 9 stores the image data read from the video frame memory 4.
Only the image data at the designated cursor position is stored. At this time, the image data read from the video frame memory 4 is transmitted to the monitor 7 together with the graphic data as usual.
And the data extractor has no effect on the radar or sonar video image.

The luminance level detecting section 10 extracts luminance data from the image data fetched into the data register 9, detects the luminance level at the designated cursor position, and outputs it to the CPU 1. CPU1 that has input the luminance level
In the generated graphic data, the image data is synthesized with data for displaying the luminance level on the screen using symbols or numerical values, and written into the graphic data frame memory 3.

In this way, the luminance level at the designated cursor position can be displayed on the monitor 7 without affecting the video image of the radar or sonar.

If the same function as that of the luminance level detection unit 10 is realized by software, only the data extraction unit needs to be provided as hardware, and an increase in circuit scale can be suppressed.

[0024]

As described in detail above, the display device according to the present invention extracts the image data corresponding to the designated cursor position from the image data read out from the video image memory for monitor display, and Is used to detect the luminance level and display the graphic. For this reason, the image data read from the video image memory is displayed on the monitor as usual, and is not affected at all by the brightness level detection. Accordingly, the video display of the radar or the sonar becomes accurate information in time, and an objective luminance level display can be obtained without impairing the reliability of the display.

[Brief description of the drawings]

FIG. 1 is a block diagram showing one embodiment of a display device according to the present invention.

FIG. 2 is a block diagram illustrating an example of a conventional display device.

[Explanation of symbols]

 Reference Signs List 1 CPU 2 Casa generator 3 Frame memory for graphics 4 Frame memory for video 5 Look-up table memory 6 D / A converter 7 Monitor 8 Cursor position detection circuit 9 Data register 10 Brightness level detection unit

Claims (2)

(57) [Claims] 1. A display device for displaying a video signal obtained from a radar or a sonar on a monitor together with graphic data on a monitor, wherein a video image memory capable of storing at least one frame or one field of the video signal as digital data. At least one frame or one
A graphic image memory capable of storing fields, synthesizing means for reading the video image data and the graphic data from the video image memory and the graphic image memory, respectively, and synthesizing them for display on the monitor; and A data extraction unit that extracts video image data corresponding to a designated position from the video image data read for the monitor display; and a luminance level of the video image data extracted by the data extraction unit. A display device, comprising: a luminance level detecting means for detecting; and a control means for inserting luminance data for displaying the detected luminance level on a screen into the graphic data. 2. A designated position detecting circuit for specifying the designated position and outputting a position detection signal at a timing corresponding to the designated position among read timings from the video image memory; The display device according to claim 1, further comprising: a data memory that stores video image data according to the position detection signal among video image data read from the image memory.