JPH05297847A - Overlay display device - Google Patents

Abstract

PURPOSE:To excellently discriminate overlay data from a gradational image with simple constitution by effectively utilizing display gradation ranges. CONSTITUTION:This overlay display device 1 makes an overlay display of characters, etc., on an image for diagnosis, and is equipped with an image memory 3 which stores the image data for diagnosis, an overlay memory 4 which stores white character data B and character display area data C added thereto, a 1st LUT 6 which makes the image data for diagnosis correspond with the full range of display gradations, a 2nd LUT 11 which makes the image data for diagnosis correspond with, for example, a 0-90% range narrower than the full range of the display gradations, and a selector consisting of an OR circuit 9 which selects the 1st LUT 6 or 2nd LUT 11 according to character display area data and an inverter 10. The cursor display area data are not added to a cursor and the 1st LUT 6 or 2nd LUT 11 is selected according to a cursor ON/OFF signal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an overlay display device, and more particularly to an overlay display device for overlay-displaying characters, figures, cursors, etc. on a gradation image.

[0002]

2. Description of the Related Art A display device having a 10% brightness enhancement function is well known in order to properly distinguish overlay data such as characters and a cursor to be overlaid on a gradation image displayed on a screen from the gradation image. Has been.

FIG. 8 is an explanatory diagram of a display gradation range of a display device having a 10% brightness increasing function. Even when the gradation image covers the full range of the gradation image, the overlay data can be satisfactorily discriminated from the gradation image due to the difference in display gradation of 10%.

As another conventional technique, for example, a white character, a white cursor, or the like is surrounded by a black border, and an overlay display is performed on the gradation image so that the character, the cursor, or the like can be well distinguished from the gradation image. Is mentioned.

[0005]

However, in the display device having the 10% brightness enhancement function, the grayscale image range is 90% of the display grayscale range regardless of the presence or absence of overlay data. The remaining 10% of the tuning range
There is a problem that is not used effectively. In addition, there is a problem that the structure becomes special. Further, in the other conventional techniques, there is a problem that the structure for edging around characters and cursors becomes complicated. Therefore, an object of the present invention is to provide an overlay display device having a simple structure and capable of effectively identifying overlay data from a grayscale image by effectively using a display grayscale range.

[0006]

SUMMARY OF THE INVENTION An overlay display device of the present invention is an overlay display device for displaying overlay data of characters, figures, cursors and the like on a grayscale image, and an image storage for storing grayscale image data. First means for associating the overlay data and the grayscale image data in the full range of the display grayscale range, and the overlay storage means for storing the overlay data and the overlay display area data for overlay display added to the overlay data.
Selection table, a second look-up table for associating the gradation image data with a range less than the full range of the display gradation range, and the first look-up table for pixels outside the overlay display area. However, the pixel in the overlay display area is provided with a look-up table selecting means for selecting the second look-up table.

In the above structure, the overlay display area data is not added to the cursor, the first lookup table is selected when the cursor is not displayed in the overlay, and the second lookup table is selected when the cursor is displayed in the overlay. It is preferable to further include cursor-dependent selection means for selecting a table.

[0008]

In the overlay display device of the present invention, the image storage means stores the gradation image data, and the overlay storage means stores the overlay data and the overlay display area data for overlay display added to the overlay data. .. The gradation image data is associated with the full range of the display gradation range in the first look-up table, and is associated with the range less than the full range of the display gradation range in the second look-up table. The look-up table selection means selects the first look-up table for pixels outside the overlay display area, and selects the second look-up table for pixels within the overlay display area.

That is, in the pixels outside the overlay display area, the full range of the display gradation range is allocated to the gradation image, and in the pixels inside the overlay display area, there is a margin in the display gradation range in addition to the allocation to the gradation image. become. Therefore, it is possible to display the overlay data in the overlay display area on the gradation image in an overlay manner, and to distinguish the overlay data from the gradation image satisfactorily by the margin remaining in the display gradation range.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in more detail below with reference to the embodiments shown in the drawings. However, this does not limit the present invention. FIG. 1 is a block diagram of an embodiment of the overlay display device of the present invention. In the overlay display device 1, the CPU 2 includes a CT device and an MRI.
The diagnostic image obtained from the equipment, ultrasonic diagnostic equipment, etc.
It is stored in the image memory 3 as diagnostic image data. Characters, graphics, cursors, etc. to be displayed in overlay on the diagnostic image are used as overlay data, and the overlay display area for each overlay data for overlay display is stored in the overlay memory 4 as overlay display area data. However, there is no overlay display area data for the cursor.

As shown in FIG. 2, assuming that the character [T] is displayed overlaid on the diagnostic image G,
M corresponds to overlay data, and R including M corresponds to overlay display area data. The address generator 5
The image memory 3 is synchronized with the pixel clock signal A.
A read display address signal for reading data at a predetermined display address in the overlay memory 4 is generated.

If only the diagnostic image is displayed (substantially when no data is stored in the overlay memory 4, a cursor ON / OFF signal described later is [OFF]).
, The diagnostic image data read from the image memory 3 is stored in the first lookup table (first
The LUT 6 outputs the brightness gradation data associated with the brightness gradations 0 to 255 as shown in FIG. 3 and is input to the DA converter 8 via the combiner 7 (at this time, there is no combiner 7). Is equivalent to.). The DA converter 8 converts the input luminance gradation data into a video signal in which the luminance gradations 0 to 255 correspond to the full range of the display gradation range and outputs the video signal.
That is, the full range of the display gradation range is assigned to the diagnostic image.

Next, for example, the case of displaying characters on the diagnostic image with the maximum brightness (white) in the display gradation range in an overlay manner will be described with reference to the time chart of FIG.
The overlay memory 4 stores the overlay data in FIG.
It is assumed that white character data B corresponding to M is stored, and character display area data C corresponding to R in FIG. 2 is stored as overlay display area data.

Image data for diagnosis is output from the image memory 3 in response to the read display address signal. Further, the white character data B is output from the overlay memory 4 to the synthesizing unit 6, and the character display area data C is output to one input terminal of the OR circuit 9.

A cursor ON / OFF signal is input to the other input terminal of the OR circuit 9 to instruct whether the mode set by the user is a "cursor overlay display" mode or a "cursor overlay display mode". is doing. Here, it is assumed that the user has set a mode in which the cursor ON / OFF signal is [OFF], that is, [the cursor is not displayed in overlay].

In the pixel where the character display area data C is [Lo], that is, in the pixel outside the character display area, OR
The output of the circuit 9 is [Lo], and the output of the inverter 10 is [Hi].
Therefore, the first LUT 6 is [ON] and the second LUT 11 is [OFF]. The white character data B input to the synthesizing unit 7 is [Lo]. Therefore, as in the case of displaying only the diagnostic image described above, the full range of the display gradation range is assigned to the diagnostic image.

In the pixel whose character display area data C is [Hi], that is, in the pixel in the character display area, OR
The output of the circuit 9 is [Hi], and the output of the inverter 10 is [Lo].
Therefore, the first LUT 6 is [OFF] and the second LUT 11 is [ON]. The diagnostic image data read from the image memory 3 is output to the synthesizing unit 7 in the second LUT 11 as brightness gradation data associated with brightness gradations 0 to 230 as shown in FIG.

In the synthesizing unit 7, the white character data B from the overlay memory 4 among the inputted luminance gradation data is [Hi].
The luminance gradation data of which the luminance gradation is set to 255 is output to the DA conversion unit 8. The DA converter 8 converts the combined luminance gradation data into a video signal F whose luminance gradations 0 to 255 correspond to the full range of the display gradation range, and outputs the video signal F.

In this way, the white characters are displayed in the character display area on the diagnostic image as an overlay display, and can be well distinguished from the diagnostic image by the difference in display gradation of at least 10% from the character display area. it can. Further, unlike the conventional example in which a white character is simply bordered in black, display gradations 0 to 230 are displayed in the overlay display area around the white character.
The diagnostic image can be recognized with. The two-dot chain line f in the figure corresponds to the video signal when the white character data B and the character display area data C are set to [Lo].

When the user has set the cursor ON / OFF signal to [ON], that is, the [cursor overlay display] mode, the output of the OR circuit 9 is [Hi] and the output of the inverter 10 is [Hi]. Lo], the first LUT6 is [OFF],
Since the second LUT 11 is [ON], display gradations 0 to 23
At 0, the diagnostic image is displayed. Therefore, like the white character, the cursor can be displayed in overlay with the highest brightness of the display gradation, and can be satisfactorily distinguished from the diagnostic image.

In the above embodiment, the overlay data is displayed with the highest brightness of the display gradation, but the overlay data can be displayed with the lowest brightness (black). It is also possible to blink and overlay display.

Another embodiment of the present invention is a cursor
Instead of the ON / OFF signal, there is one that selects one of the first LUT 6 and the second LUT 11 according to the movement / stop of the cursor. Another example is blinking the cursor when it is stopped.

As still another embodiment of the present invention, in place of the second LUT 11, diagnostic image data is associated with luminance gradations 0 to 230 as shown by the solid line in FIG.
The thing provided with LUT is mentioned. As still another embodiment of the present invention, in place of the second LUT 11, there is provided a fourth LUT which associates diagnostic image data with brightness gradations 0 to 230 as shown by the solid line in FIG.

[0024]

According to the overlay display device of the present invention, the overlay data can be satisfactorily discriminated from the gradation image with a simple structure and by effectively using the full range of the display gradation.

[Brief description of drawings]

FIG. 1 is a block diagram of an embodiment of an overlay display device of the present invention.

FIG. 2 is an explanatory diagram of overlay data and overlay display area data according to the apparatus of FIG.

FIG. 3 is an explanatory diagram of a first LUT of the apparatus shown in FIG.

4 is an explanatory diagram of a second LUT of the apparatus of FIG.

5 is a time chart of each data and the like in the apparatus of FIG.

FIG. 6 is a third LUT according to still another embodiment of the present invention.
FIG.

FIG. 7 is a fourth L according to still another embodiment of the present invention.
It is explanatory drawing of UT.

FIG. 8 is an explanatory diagram of a display gradation range of a display device having a 10% brightness up function.

[Explanation of symbols]

 1 Overlay Display Device 2 CPU 3 Image Memory 4 Overlay Memory 6 1st LUT 8 DA Converter 9 OR Circuit 11 2nd LUT

Continuation of front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display area G09G 5/36 9177-5G

Claims (2)

[Claims] 1. An overlay display device for displaying overlay data of characters, figures, cursors, etc. on a gradation image in an overlay manner. Image storage means for storing gradation image data, and overlay data and the overlay data. Overlay storage means for storing overlay display area data for overlay display, a first lookup table for associating gradation image data with a full range of display gradation range, and gradation image data for display gradation A second look-up table that is associated with a range less than the full range, and the first look-up table is selected for pixels outside the overlay display area, and the second look-up table is selected for pixels within the overlay display area. Lookup table selection Lookup table selection Overlay display device characterized by that and a stage. 2. The overlay display device according to claim 1, wherein the overlay display area data is not given to the cursor, and the first lookup table is selected when the cursor is not displayed in the overlay, and the cursor is displayed in the overlay. The overlay display device further comprising cursor-dependent selection means for selecting the second look-up table at the time of performing.