JP3090974B2 - Video 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 an image display device having a small-screen display function in a television receiver, a monitor display, or the like.

[0002]

2. Description of the Related Art Conventionally, in a television receiver or a monitor display having a small screen display function, the entire data of an image to be displayed as a small screen is compressed and written in a memory, and the compressed data is displayed on a main screen. The child screen is displayed on the parent screen by reading the timing in accordance with the timing of the position. FIG. 4A is a block diagram of the conventional example.

[0003] The video signal for the child screen input to the input terminal T2 is subjected to compression processing such as thinning-out or calculation by the compression section 7, sent to the storage section 8, and stored in the storage section 8. The data stored in the storage unit 8 is read out in accordance with a command from the timing control unit 6 in accordance with the timing of the display position to be displayed on the parent screen, and is supplied to the mixing unit 9 from the input terminal T1. The video signal is synthesized with the video signal of the screen, is derived from the output terminal T3, and is sent to a well-known display unit (not shown) to display a sub-screen on a part of the main screen. When the capacity of the storage unit 8 is sufficiently large, first, as shown in FIG. 3B, data of the entire small screen is stored as it is, and a compression process is performed at the time of reading, or a thinning operation is performed before the storage unit. A method of providing a compression unit for performing the compression when reading data from the storage unit is also adopted.

[0004]

In recent years, the size of a display device such as a television receiver or a monitor display has been remarkably increased, and the size of a small screen is approaching that of a small television. It is even becoming so. On the other hand, a screen of a television or the like often has a content that does not necessarily require viewing the entire screen, such as a sumo broadcast or a movie of a Sinesco size.

In the above-mentioned conventional apparatus, the compression ratio of a compression unit provided before or after the storage unit for storing the information of the child screen and for compressing the information of the child screen is fixed. A part or all of the preset screen is always displayed at the preset compression ratio, and the problem that the desired position of the child screen cannot be displayed at the desired compression ratio according to the video content. there were.

[0006]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a video display device in which a sub-screen is displayed on a part of a main screen. Means for causing the video signal of the small screen to be displayed , a timing control unit for deriving a cropping range designation control signal for designating a cropping range of the video signal of the small screen according to the cropping frame, and displaying the video signal of the small screen.
A compression unit with variable compression ratios in the horizontal and vertical directions that compresses at a compression ratio according to the compression ratio of the child screen determined by the size of the cropped frame, and arbitrary compression in the horizontal and vertical directions by the compression unit A storage unit for storing the video signal of the child screen in the extraction range specified by the extraction range designation control signal from the timing control unit, and a child screen derived from the storage unit to a predetermined portion of the video signal of the parent screen. And a mixing unit for synthesizing the above information.

[0007] According to the above configuration, the video signal of the small picture, which is compressed at a desired compression rate by the compression section having a variable compression rate in the horizontal and vertical directions, is output by the cutout range designation control signal from the timing control section. A desired clipping range of the child screen is designated and stored in the storage unit. The cutting range and pressure
The reduction ratio is specified according to the cutout frame displayed on the screen .
The video signal compressed at the desired compression ratio of the child screen stored in the storage unit and cut out at the desired cut-out range receives the control signal from the timing control unit, and receives the control signal from the timing control unit. The image is synthesized and displayed at a predetermined position.

[0008]

FIG. 1 is a block diagram showing a configuration of a main part of an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a compression ratio control unit for controlling the compression ratio of the child screen, and reference numeral 2 denotes a control signal from the compression ratio control unit 1 for compressing the video signal of the child screen at a desired compression ratio in the horizontal and vertical directions. The compression unit 2 has a variable compression ratio in the horizontal and vertical directions which is ideally stepless and practically several steps. A timing control unit 3 generates a cut-out range specifying control signal for specifying a cut-out range of a small screen and a timing signal to each unit.

Reference numeral 4 denotes a storage unit for storing the video signal of the cut-out range of the small screen compressed by the compression unit 2 by the cut-out range designation control signal from the timing control unit 3, and 5 denotes the timing from the timing control unit 3. The mixing unit combines the video signal of the child screen stored in the storage unit 4 with the video signal of the main screen at a predetermined position by a signal.

Therefore, the video signal of the child screen applied to the input terminal T2 enters the compression unit 2 in which the compression ratio is variable in the horizontal and vertical directions, and the compression ratio in the horizontal and vertical directions from the compression ratio control unit 1 And are supplied to the storage unit 4. The storage unit 4 cuts out only the designated range in the child screen based on the cutout range designation control signal from the timing control unit 3, and stores this.

Thereafter, in the same manner as in the prior art, the storage section 4 compresses the desired cut-out range of the child screen at a desired compression ratio in accordance with the display timing of the parent screen according to the timing signal from the timing control section 3. The mixed video signal is read out from the input video signal, the video signal of the main screen supplied from the input terminal T1 is synthesized by the mixing unit 5, and the video signal obtained by synthesizing the main screen in the desired form from the output terminal T3 is derived. Although not shown, this video signal is displayed on a display unit via a conventionally known video amplifier circuit.

FIG. 2 illustrates a display form of a display screen according to the present invention. FIG. 2A shows a case where the size of the child screen display is set to 1/4 of that of the parent screen 20 and the child screen 11 compressed at the lower right of the parent screen is synthesized. / 4, 1/2, 1/1 are exemplified.

FIG. 2B shows a case where the size of the sub-screen display is set to の of the size of the main screen 20 and the sub-screen 11 compressed at the upper right of the main screen 20 is synthesized. The ratio is set to 1/1, and the cutout ranges 12, 13, and 14 of the child screen 10 are set to the upper right, upper left, and the center slightly lower left. This means that the child screen 10 can be displayed at an arbitrary position on the parent screen 20 as before, and the area of the child screen 10 can be arbitrarily set with respect to the area of the parent screen 20 (in this example, the child screen 10 can be displayed). The area of the screen 10 is 1/4 of the area of the parent screen 20), and the child screen 11 combined with the parent screen 20 can display an arbitrary range of the image of the original child screen 11 at an arbitrary compression ratio. I have.

FIG. 3 exemplifies a case in which a cut-out range and a compression ratio of a small-screen image are designated. FIG. 3A shows a cutout frame 15 corresponding to a grandchild screen on the child screen 11, determines the compression ratio based on the size of the cutout frame 15, and displays the child screen at the position of the cutout frame 15. This is an example of a method of specifying a range. First, as shown in a-1, the entirety of the child screen synthesized at a predetermined position on the parent screen 20 is compressed and displayed, and a cutout frame 15 corresponding to the grandchild screen is displayed in the child screen 11. Then, the compression rate of the child screen is finally determined by the size of the cutout frame 15 (in this example, it becomes 1/3). Next, the cutout frame 15 is moved to an arbitrary portion of the child screen 11 to be displayed as shown in a-2, and the moved cutout frame 15 is moved to the main screen 20 as shown in a-3. It is displayed at the desired position (lower right in the figure). In the example shown, the child screen is 1/3
Is displayed in compressed format.

FIG. 3B shows the child screen 10 displayed on the entire surface of the parent screen 20 in advance, and the same as in FIG.
5 illustrates a method of specifying the compression ratio and the display range of the sub-screen 10. First, the child screen 10 is displayed on the entire main screen as shown in b-1, the compression rate of the child screen is determined by the size of the cutout frame 15, and then the child screen 10 is displayed as shown in b-2. The extraction frame 15 is moved to a desired position, the display range of the specified sub-screen is determined at the position of the extraction frame 15, and then the extraction frame 15 is moved to a predetermined position on the parent screen 20 as shown in b-3. (The lower right in this example), and the child screen is displayed at a predetermined size at this position. In the example shown in the figure, the composite screen is composed of the parent screen and the child screen compressed to half.

FIG. 3 (c) shows the image of the child screen 11 hidden behind the parent screen 20, which can be seen by the cutout frame 15, and the display of the child screen is designated. As shown in (1), the cutout frame 15 of the child screen is displayed on the display screen of the parent screen 2, and the compression rate of the child screen is determined by the size of the cutout frame 15. When the child screen is displayed at a size of 1/4 of the parent screen, the compression rate of the child screen exemplified in c-1 is 1/1.

Next, as shown in c-2, a part of the uncompressed child screen hidden behind the parent screen is displayed in the extraction frame 15, and the extraction frame 15 is moved to Is specified, and the extraction frame 15 is moved to an arbitrary position on the parent screen 20 as shown in c-3 to obtain a composite screen of the parent screen and the child screen.

As described above, various methods have been exemplified for synthesizing the parent screen and the child screen. However, since the individual techniques are conventionally well-known, a detailed description thereof will be omitted.

According to the embodiment of the present invention described above, a small screen displayed without compression is displayed without losing the definition of the original screen, although only a part thereof is displayed. And a powerful child screen can be displayed as the image quality of the monitor display increases. In addition, by independently changing the horizontal and vertical compression ratios, a cinesco-sized image or the like can be displayed in a full sub-screen, which can contribute to effective use of the screen. In addition, since it is practically difficult to set the compression ratio of the sub-screen in a stepless manner, as shown in FIG. 2, the compression ratio is selected in several steps such as ４ ，, 等. In the future, if multi-stage compression can be performed easily and inexpensively, more detailed correspondence will be possible.

Since the processing after the storage unit is the same as that of the conventional circuit, a function of switching between 1/4 and 1/1 (ie, performing the conventional compression and not performing the compression) and designating the extraction range. Even with a simple device simply attached, a certain purpose can be sufficiently achieved. In a device with a sufficiently large memory capacity, there is a method in which the original small-screen signal is not compressed or stored in such a way that it is simply thinned out, and is compressed according to the final data size at the time of reading. Only a specified range from a large amount of data may be read while being compressed according to an instruction from the control unit.

[0021]

As described above, according to the present invention, an arbitrary area of a picture of a child screen can be synthesized at a predetermined position of a parent screen, so that the whole or arbitrary part of the child screen is displayed on a part of the parent screen. It is possible to provide a video display device having a function of performing Further, Ri compression ratio of the displayed cutout frame size in sub-screen video signal KOR, even in a high-definition when the compression rate of the child screen is low child screen on the synthesis screen, recent video display The display function of the child screen can be enhanced in combination with the enlargement of the device and the high definition. Further, since the compression ratio of the child screen is variable in the horizontal and vertical directions, a cinema-size movie or the like can be displayed on the entire child screen, so that the child screen can be further multi-functional. Further, according to the present invention, by displaying the cutout frame 15 on the screen, it is possible to easily specify the cutout range, compression, and the like of the sub-screen, so that the operability is very good and convenient.

[Brief description of the drawings]

FIG. 1 is a block diagram of a main part of an embodiment of the present invention.

FIG. 2 is a diagram showing a screen display example according to the present invention.

FIG. 3 is a diagram showing another screen display example according to the present invention.

FIG. 4 is a block diagram of a conventional example.

[Explanation of symbols]

 2 compression unit 3 timing control unit 4 storage unit 5 mixing unit

Claims (1)

(57) [Claims] 1. A video display device which displays a sub-screen on a part of a main screen, means for displaying a cut-out frame of the sub-screen on the screen, and an image of the sub-screen according to the cut-out frame. A timing control unit for deriving a cut-out range specifying control signal for specifying a signal cut-out range, and displaying a video signal of a small screen.
Compressor with a variable compression ratio in the horizontal and vertical directions that compresses at the compression ratio according to the compression rate of the child screen determined by the size of the cropped frame, and arbitrary compression in the horizontal and vertical directions by the compression unit A storage unit for storing the video signal of the child screen in the extraction range determined by the extraction range designation control signal from the timing control unit, and a child screen derived from the storage unit to a predetermined portion of the video signal of the main screen. And a mixing unit for synthesizing the above information.