JPH07322168A - Television receiver - Google Patents

Abstract

PURPOSE:To display a picture signal in the most preferable state even in the case of switching and input of plural picture signals different by aspect ratios by separating a picture signal and a discrimination control signal by a separating means and discriminating the aspect ratio of the picture signal in the transmission signal and converting the aspect ratio in accordance with the discrimination control signal to obtain an output picture. CONSTITUTION:The separating means which separates a picture signal V and a discrimination control signal S indicating the aspect ratio of the picture signal V from a transmission signal T, a mode holding means which holds preliminarily set first mode information M1, and a mode conversion means which converts first mode information M1 to second mode information M2 in accordance with the discrimination control signal S are provided. An aspect ratio conversion means converts the aspect ratio in accordance with second mode information M2 to obtain an output picture O. A display means displays this output picture O. This, the aspect ratio is converted at viewer's choice to display the picture if the aspect ratio of the transmitted picture signal is different from that of the display means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver, and more particularly to a television receiver having an aspect ratio different between a transmission form and a display form.

[0002]

2. Description of the Related Art In the current television system (NTSC system), the aspect ratio (ratio between the horizontal and vertical lengths of the screen) is 4: 3. However, a larger aspect ratio (for example, 16: 9) is used to emphasize the sense of presence and force.
In recent years, a wide-screen receiver that converts and displays the image has been developed. In such a wide-screen receiver, the aspect ratio is converted by expanding or compressing the whole or a part of an image with the current aspect ratio (Reference 1: For example, “Special Feature High-Vision Wide-TV Receiver,” TV Magazine, Vol.47, No.
7, pp.949-955 (July, 1993)). As this aspect ratio conversion method, many methods described later are known.

On the other hand, the second generation EDTV system aiming at widening, high image quality and high sound quality while maintaining compatibility with the current television system is currently under standardization. As a method of widening, it is unofficially decided to adopt the "letter box method" in which the entire wide screen with an aspect ratio of 16: 9 is reduced and placed in the central part of the current screen, and there is a non-image area (blackness) above and below the current screen. ing.

In the second-generation EDTV system, an identification control signal for identifying the letterbox system is multiplexed with the image signal and transmitted. This multiplex position is settled on the 22nd and 285th scanning lines which are within the effective screen (reference 2: blowout, Matsuzaki, "EDTV-II.
Discrimination control signal examination, "Television Technical Report, Vol.17, No.6
5, pp.43-48, BCS'93-46 (Oct.1993)).

[0005]

For some time after the standard of the second generation EDTV system was established, the current aspect ratio (4:
It is expected that the image signal of 3) and the image signal of the letterbox system aspect ratio (16: 9) are mixed and transmitted alternately for each program, for example. In this case, it is considered as a standard to discriminate the aspect ratio by using the above-mentioned identification control signal and automatically control the aspect ratio conversion method of the wide image receiver.

However, how to control the aspect ratio conversion using the identification control signal is not specifically defined as a standard, but is left to the discretion of the manufacturer.

An object of the present invention is to specifically realize this control and provide a television receiver capable of displaying each image in the most preferable form even when a plurality of image signals having different aspect ratios are switched and input. Especially.

[0008]

In order to achieve the above object, the present invention is preset with a separating means for separating an image signal V and an identification control signal S indicating an aspect ratio of the image signal V from a transmission signal T. A mode holding means for holding the first mode information M1, a mode converting means for converting the first mode information M1 into the second mode information M2 according to the identification control signal S, and an aspect ratio according to the second mode information M2. Aspect ratio conversion means for converting to obtain an output image signal O;
Display means for displaying the output image signal O is used.

[0009]

In the separating means, the image signal V and the identification control signal S are separated in accordance with the standard of the second generation EDTV system, and the aspect ratio (first aspect ratio) of the image signal V in the transmission signal T is 16 :. It is determined whether it is 9 or 4: 3. If the identification control signal S is not multiplexed, the current television system is considered and the first aspect ratio is determined to be 4: 3.

On the other hand, in the mode holding means, the viewer prefers the aspect ratio conversion method when the aspect ratio (first aspect ratio) of the image signal V and the aspect ratio (second aspect ratio) of the display means are different. Is set in advance according to the above, and this is held as the first mode information M1. Even when images with different first aspect ratios are alternately transmitted, the first mode information M1 is always held in the mode holding unit, so that the viewer sets the mode every time the first aspect ratio changes. Does not have to be performed.

In the mode conversion means, when the first aspect ratio and the second aspect ratio are different, the second mode information M2 becomes the same as the first mode information M1, and the first aspect ratio and the second aspect information M2 are the same. If the aspect ratios of the two match, the second mode information M2 operates so as to indicate a predetermined mode (for example, a mode in which the image is neither deformed nor missing) regardless of the first mode information M1.

In the aspect ratio conversion means, the mode information M
2, the image signal V having the first aspect ratio is converted into the second aspect ratio and displayed.

By these operations, when the transmitted image signal and the aspect ratio of the display means are different from each other, the aspect ratio is converted and displayed according to the viewer's preference, and when the aspect ratios of both are the same. The image is displayed without any deformation or loss.

The second aspect ratio is set to 16: 9 according to the letterbox aspect ratio, or
Alternatively, the aspect ratio of the current television system is preferably set to 4: 3.

[0015]

FIG. 1 is a block diagram showing an embodiment of the present invention. In the figure, a separation means 1 separates a transmission signal T (including a signal after broadcasting, communication, storage, editing, processing, etc.) into an image signal V and an identification control signal S. This separating means 1
Then, as described above, the identification control signal S multiplexed on the 22nd and 285th scanning lines of the transmission signal T is separated according to the standard of the second generation EDTV system, and the aspect ratio of the image signal V ( It is determined whether the first aspect ratio) is 16: 9 or 4: 3. This separating means 1 can be easily realized by a known technique with reference to Document 2 and the like, and therefore is not particularly shown.

On the other hand, the mode holding means 2 holds the first mode information M1 (described later) set from a switch, a remote control terminal or the like by coding it in a binary number or the like. The mode holding means 2 can be easily realized by a memory or the like, and is not particularly shown.

The mode conversion means 3 converts the first mode information M1 into second mode information M2 according to the above-mentioned identification control signal S. This operation will be described in detail later.

The aspect ratio conversion means 4 converts the aspect ratio of the image signal V into an output image signal O according to the second mode information M2, and the aspect ratio (second aspect ratio) is 16: 9. It is displayed on the display means 5 (CRT, liquid crystal display, plasma discharge display, etc.).
The aspect ratio conversion means 4, as shown in the above-mentioned Document 1,
This can be realized by a known technique by performing interpolation processing of pixels or scanning lines using a line memory or a field (frame) memory, or by giving the display unit 5 a special characteristic in the linearity of horizontal / vertical deflection. .

FIG. 2 shows the operation of one embodiment of the present invention. As the form of the transmission signal T, as shown in the figure, (a) the current form of the current television system and (g) the letterbox form of the second generation EDTV system are considered. (A) In the case of the current form, it is necessary to convert the aspect ratio 4: 3 of the image signal V into the aspect ratio 16: 9 of the display means 5.
As the conversion method, the modes shown in FIGS. 6B to 6F or the eclectic (intermediate) mode of these are well known.

(B) In the whole display mode, all 4: 3 images are displayed without omission. (C) In the similar expansion mode, to prevent the image from being deformed,
Only the central portion of the 4: 3 image is expanded (enlarged) and displayed.
(D) In the horizontal expansion mode, the entire image is horizontally expanded and displayed uniformly. (E) In the local expansion mode, the visual characteristic that distortion in the peripheral portion of the screen is difficult to perceive is used to horizontally expand only the left and right edges of the screen and display the central portion without deformation. (F) In the local compression mode, only the upper and lower ends of the screen are vertically expanded and the central part is displayed without being deformed. From these modes, the viewer selects an aspect ratio conversion method according to his / her preference and holds it in the mode holding means 2 as the first mode information M1.

On the other hand, when the transmission signal T is (g) letter-box type, the aspect ratio of the image signal V and the aspect ratio of the display means 5 match, so that the image is neither deformed nor missing (h) similar expansion. Forcibly select the mode (same as (c)).

The mode conversion means 3 is a means for realizing the above-mentioned mode selection, and operates as shown in FIG. That is, the first aspect ratio indicated by the identification control signal S is
In the case of 4: 3, the second mode information M2 is the same as the first mode information M1, and in the case of 16: 9, the similar expansion mode is always used regardless of the first mode information. By this operation, even when the transmission signals of the current system and the second generation EDTV system are alternately input, each can be displayed in the most preferable form (the form set by the viewer's preference). Since this operation can be easily realized by a simple logic gate element or a switch, it is not shown in the drawing.

FIG. 4 shows a block diagram of an embodiment in which the present invention is applied to a television receiver having a 4: 3 display means. The configuration of FIG. 3 is the same as the display means 5 of the configuration shown in FIG.
Is changed to display means 9 having an aspect ratio of 4: 3. Along with this change, the operations of the mode holding unit 6, the mode converting unit 7, and the aspect ratio converting unit 8 are also changed as follows.

As shown in FIG. 5, when the transmission signal T is (a) in the current form, the first aspect ratio and the second aspect ratio are equal, and therefore the image is neither deformed nor missing (i) Whole display Display in mode. On the other hand, when the transmission signal T is in the (g) letterbox form, it is displayed in the modes of (j) to (n) in FIG.

(J) The whole display mode is the same as that of (i), and the display is performed in the transmission form as it is. At this time, the upper and lower non-image portions may be masked with a single color such as black by signal processing, or the upper and lower portions of the display means may be masked with a shield. (K) In the similar expansion mode, the entire image is expanded and displayed so that the image is not deformed. (L) In the vertical expansion mode, the image is uniformly vertically expanded and displayed so that no image portion is not displayed. (M) In the local expansion mode, only the upper and lower ends of the screen are expanded and the central part is displayed without being deformed. (N) In the local compression mode, the left and right edges of the screen are compressed, and the central portion is enlarged and displayed so as not to be deformed.
From these modes, the viewer selects a display mode according to his / her preference and holds it in the mode holding means 6 as the first mode information.

The mode conversion means 7 is a means for realizing the above-mentioned mode selection, and operates as shown in FIG. That is, the first aspect ratio indicated by the identification control signal S is
In the case of 4: 3, the second mode information M2 is always the full display mode, and in the case of 16: 9, it is the same as the first mode information. By this operation, even when the transmission signals of the current system and the second generation EDTV system are alternately input, each can be displayed in the most preferable form (the form set by the viewer's preference). Since this operation can be easily realized by a simple logic gate element or the like, it is not shown in the drawing.

Although the embodiment in which the present invention is applied to the second generation EDTV has been described above, the present invention is not limited to this, and can be applied to an HDTV of the MUSE system, a digital broadcasting television system, and the like.

[0028]

According to the present invention, even when the aspect ratio differs between the transmission mode and the display mode, the aspect conversion can be performed in the most preferable mode for display.

[Brief description of drawings]

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

FIG. 2 is an explanatory diagram of the operation of the embodiment of the present invention.

FIG. 3 is an explanatory diagram of an operation of one embodiment of the present invention.

FIG. 4 is a block diagram of another embodiment of the present invention.

FIG. 5 is an explanatory diagram of an operation of another embodiment of the present invention.

FIG. 6 is an explanatory diagram of the operation of another embodiment of the present invention.

[Explanation of symbols]

1 ... Separation means, 2, 6 ... Mode holding means, 3, 7 ... Mode conversion means, 4, 8 ... Aspect ratio conversion means, 5, 9 ...
Display means.

Claims (7)

[Claims] 1. A separation means for separating an image signal from a transmission signal and an identification control signal indicating an aspect ratio of the image signal, a mode holding means for holding preset first mode information, and the first control means according to the identification control signal. Mode conversion means for converting one mode information into second mode information, aspect ratio conversion means for converting an aspect ratio according to the second mode information to obtain an output image signal, and display for displaying the output image signal A television receiver provided with means. 2. The mode conversion means according to claim 1, wherein when the first aspect ratio indicated by the identification control signal and the second aspect ratio of the screen of the display means are different, the second mode information is It becomes the same as the first mode information, and when the first aspect ratio and the second aspect ratio match, the second mode information becomes a predetermined mode regardless of the first mode information. Television receiver that works like a TV receiver. 3. The television receiver according to claim 2, wherein the predetermined mode is a mode indicating an aspect ratio conversion method in which an image is neither deformed nor missing. 4. A television receiver according to claim 1, wherein said separating means is means for separating said identification control signal from a scanning line signal within the effective screen in said transmission signal. 5. A television image receiving apparatus according to claim 1, wherein said separating means is a means for separating said identification control signal from the 22nd scanning line signal and the 285th scanning line signal in said transmission signal. Machine. 6. The television receiver according to claim 1, wherein the second aspect ratio is 16: 9. 7. The television receiver according to claim 1, wherein the second aspect ratio is 4: 3.