JP2003174601A - Video display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a video display device that makes the burning of mask parts inconspicuous at a border between video display parts and the mask parts in the case of displaying a video image with an aspect ratio different from the aspect ratio of a video display screen. <P>SOLUTION: When a display section 2 displays an input video signal (RGB) of a video signal processing section 1 in a way of a letter box or a side panel, a clock section 6 starts time count on the basis of detection by a display mode detection section 3, and a display rate detection section 4 detects the display rate of the video signal. When the display rate is equal to zero (the video signal shows a pitch-black video image) or a prescribed reference rate or below after a lapse of a prescribed time, a display position control section 5 moves the video display position of the display section through the video signal processing section according to a signal from a control section 11. Alternatively, a setting section 7 may set a value (display rate) at which no sense of incongruity is felt even at the movement of the display position. Accordingly, the processes above can make the slope of burning at the border between the video display parts and the mask parts gentle and make the difference of the luminance and the color of the video image around the border inconspicuous in the case of video display in a full mode. <P>COPYRIGHT: (C)2003,JPO

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, and more particularly to a device suitable for displaying an image having an aspect ratio different from that of the screen of a display section.

[0002]

2. Description of the Related Art In an image display device, for example, as shown in FIG. 2, a horizontally long image (for example, DV image) having an aspect ratio of 16: 9 is displayed on a screen 21 of a display section having an aspect ratio (horizontal: vertical) of 4: 3.
When a movie (playback from D) is displayed in letterbox, the upper and lower parts of the screen 21 of the display part are the mask part 23 where the image is not displayed. Therefore, when used for a long time in such a state, compared to the mask part 23. As a result, deterioration of the performance of the image display portion 22 progresses, and so-called image sticking occurs. As a result, when an image with an aspect ratio of 4: 3 is displayed in full mode on the screen 21 of this display unit, a difference in brightness and color occurs between the central portion and the upper and lower portions of the image, and this difference is particularly noticeable at the boundary 24. . This is also the same when a side panel image with an aspect ratio of 4: 3 is displayed on the screen of the display with an aspect ratio of 16: 9.
When a 16: 9 horizontally long image is displayed in full mode on the screen of this display unit, there is a difference in brightness and color between the central portion and the left and right portions of the displayed image. As a countermeasure against this, for example, the image display position is moved up and down (left and right) to make the slope of performance deterioration (burn-in) near the boundary 24 between the image display portion 22 and the mask portion 23 gentle, and to reduce the brightness and color. There are things that make the difference inconspicuous. The image display position is moved, for example, at an appropriately determined time or when the display mode is switched (the display image is switched from the aspect ratio 16: 9 to the aspect ratio 4: 3, When the aspect ratio is changed to 16: 9, the image having the aspect ratio of 16: 9 is moved to a position different from the position where the image was previously displayed and displayed). However, what is done at an appropriately set time is
Since the image moves while watching the screen, it may be misunderstood that the viewer may feel discomfort or the device may have malfunctioned.
There is a problem that it is not effective when used in the same mode for a long time.

[0003]

In the case where the image is difficult to be noticed as an afterimage, the discomfort given to the viewer is reduced even if the image display position is moved. In view of such a point, the present invention is such that the image display in modes other than the full mode continues for a predetermined time, and the entire image is dark, the display rate (average brightness level) is low, or the peripheral portion of the image is When it is dark, moving the image display position makes it less likely that the movement of the image display position will give the viewer a sense of incongruity, while grading the burn-in slope of the display screen at the boundary between the image display part and the mask part. The purpose is to make the difference in brightness and color of the image due to image sticking less noticeable.

[0004]

In order to achieve the above object, a video display device of the present invention performs a predetermined signal processing on a video signal by a video signal processing section and sends it to a display section to display a video on a screen. A display mode detection unit for detecting whether the image of the video signal is a video signal displayed on the screen of the display unit in letterbox mode display, side panel mode display, or full mode display. A display rate detecting section for detecting the display rate of the video signal, a display position control section for controlling a video display position on the display section via the video signal processing section, the display mode detecting section, and the display rate detecting section. And a control unit for controlling the display position control unit, and when a display mode other than the full mode display is detected by the display mode detection unit, the display ratio detection unit detects the display mode. So as to move the image display position of the display unit via the video signal processing unit by the display position control unit based on the display rate.

In this case, a clock unit is provided, and when the display mode detecting unit detects a display mode other than the full mode display, the clock unit starts clocking, and when the detection continues for a predetermined time or longer, the image display position. May be moved.

When the display ratio detected by the display ratio detection unit is zero (black image), the image display position on the display unit is moved, or when the display ratio is below a predetermined display ratio, the image display position on the display unit is changed. You may move.

Alternatively, the display rate detecting section detects the display rate of the peripheral portion of the image by the image signal,
The video display position on the display unit may be moved when the display ratio of the peripheral portion of the video detected by the display ratio detection unit is zero or less than or equal to a predetermined display ratio.

A setting unit for setting a display ratio as a reference when moving the image display position is provided, and the display ratio detected by the display ratio detecting unit is equal to or less than the display ratio set by the setting unit. At this time, the image display position on the display unit may be moved.

Further, the display position control section stores the image display position immediately before the image display is turned off for each display mode for each display mode other than the full mode, and the input image is displayed when the next image display is turned on. You may make it respectively display in the position displayed last time according to display mode. in this case,
The duration of video display at the video display position immediately before the video display is turned off is stored, and when the next video display is turned on, after the time obtained by subtracting the previous duration of the display mode has elapsed, The first video display position may be moved.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described based on examples with reference to the drawings. FIG. 1 is a block diagram of a main part of an embodiment of a video display device according to the present invention.
Video signal from the B terminal or the RGB matrix section 8 (R
Video signal processing unit for processing (GB signal), 2 is a PDP
(Plasma display panel), liquid crystal panel, display unit constructed by using a cathode ray tube, etc., 3 is a letter box mode display, a side panel mode display on the screen of the display unit 2 the video signal input to the video signal processing unit 1. , Or a full-mode display mode, the display mode detection unit 4 detects the display ratio (average luminance level) of the video signal input to the video signal processing unit 1. A display ratio detection unit, 5 is a display position control unit that controls the video display position of the display unit 2 via the video signal processing unit 1, and 6 is a clock that starts when the display mode detection unit 3 detects anything other than full mode display. A clock unit that measures a predetermined time,
Reference numeral 7 is a setting unit for the viewer to set a display rate for use as a reference when moving the video display position, and 8 is Y from the D terminal.
(Luminance) component signal and Pb, Pr color difference signal,
Alternatively, the Y signal from the video demodulation unit 9 and an RGB matrix unit that matrix-converts the U and V color difference signals into an RGB signal, the video demodulation unit 9 outputs the Y and C signals from the Y / C separation unit 10, or the S terminal. Ys (luminance) and Cs (color) signals are set to Y
For demodulating signals into color difference signals of U and V, Y / C separation unit
10 is for separating the composite signal from the CVBS (Composite Video Burst Synch) terminal into Y and C (color) signals, 11
Is a control unit that controls each unit.

Next, the operation of the image display device according to the present invention will be described. When the RGB signal is input from the RGB terminal, the RGB signal is input to the video signal processing unit 1, and when the Y signal and the color difference signals of Pb and Pr are input from the D terminal, the RGB signal is input.
The matrix section 8 performs matrix conversion into RGB signals and inputs the RGB signals to the video signal processing section 1. When Ys and Cs signals are input from the S terminal, the video demodulation section 9 converts the Y signals and U and V color difference signals. , RGB matrix section 8 performs matrix conversion into RGB signals and inputs them to the video signal processing section 1. When a video signal is input from the CVBS terminal, the Y / C separation section 10 separates them into Y and C signals, and performs video demodulation. The section 9 converts the Y signal into color difference signals of U and V, and the RGB matrix section 8 performs matrix conversion into an RGB signal and inputs the RGB signal to the video signal processing section 1. And
The video signal processing unit 1 performs signal processing such as gamma correction when a PDP or a liquid crystal panel is used for the display unit 2, and performs video display position control processing based on a signal from the display position control unit 5. .

When the display mode detection unit 3 detects a mode other than the full mode display, the clock unit 6 starts clocking,
After this timekeeping is continued for a predetermined time, when the display rate of the video signal detected by the display rate detecting section 4 becomes zero, that is, when the video becomes pitch-dark, or a picture close to pitch-black (display rate detecting section 4). When the display ratio detected in step (1) is less than or equal to a predetermined reference value), the display position control section 5 causes the display section 2 via the video signal processing section 1 based on the signal from the control section 11.
The video display position displayed on the screen is appropriately moved to the upper side or the lower side in the case of letterbox display, and to the left or the right side in the case of side panel display. This allows
Screen 21 of the display shown in Figure 2 (example of letterbox display)
In the vicinity of the boundary 24 between the image display portion 22 and the mask portion 23, the burn-in inclination becomes gentle, and when the full-mode image is displayed on the screen 21 of the display unit, the brightness of the image near the boundary 24 and The color difference is less noticeable.

If the peripheral portion of the image (the upper side, the lower side, or the left side, the right side of the image) is dark, the viewer does not feel a sense of discomfort even if the image display position is moved. Therefore, the display rate detection unit 4 detects the display rate of the peripheral portion (upper side, lower side portion or left side, right side portion of the image) of the image, and when the display rate of this part is zero or less than a predetermined reference value, the display position The video display position of the display unit 2 may be moved by the control unit 4 via the video signal processing unit 1.

Further, the display ratio which allows the movement of the image display position may be set by the operation of the setting section 7. That is, the viewer can set a value (display rate) that the viewer feels to be comfortable even if the video display position is moved if the display rate is less than this. As a result, the image display position of the display unit 2 is controlled by the display position control unit 5 when the detection value of the display ratio detection unit 4 (entire image or the peripheral portion of the image) is less than or equal to the display ratio set by the setting unit 7. It is moved upward or downward, or leftward or rightward via the signal processing unit 1. The image display position is moved, for example, by a predetermined number of pixels (for example, one pixel), and the predetermined number of pixels is moved in one direction and then the predetermined number of pixels is moved in the opposite direction, or the end of the display image is displayed. After moving to the position where the part 2 touches the edge of the screen, it moves in the opposite direction to the position where it touches the edge of the screen.

Further, the display position control unit 5 stores the image display position immediately before the image display is turned off for each display mode for each display mode other than the full mode, and when the image display is turned on next time, each display mode is stored. May be displayed at the previously displayed position, and thereafter, as in the above case, the image display position may be moved from the black screen or when the display ratio is equal to or lower than a predetermined reference value. In this case, the display position control unit 5 stores the display duration at the video display position immediately before the video display is turned off, and the next time the video display is turned on, the video is displayed in the same mode as that immediately before the video display was turned off. In this case, the first video display position may be moved after the time obtained by subtracting the stored previous display duration time has elapsed. As a result, it is possible to reduce the deviation of the image display position and make the inclination of image sticking inconspicuous.

[0016]

As described above, according to the image display device of the present invention, the image display (letter box display or side panel display) other than the full mode is continued for a predetermined time or longer, and the entire image is dark. , Or if the display rate is lower than the reference value, or if the peripheral part of the image is dark or the display rate is lower than the reference value, the image display position is moved. The image burn-in slope of the screen of the display unit becomes gentle, and when the image is displayed in the full mode on the screen of the display unit, the difference in brightness and color of the image near the boundary becomes less noticeable. Moreover, since the movement of the image display position is performed in the image state where the viewer cannot easily notice it, it is possible to reduce the possibility that the viewer feels uncomfortable due to the movement of the image display position. It should be noted that by setting the value (display rate) at which the viewer feels that there is no discomfort even if the image display position is moved if the display rate is lower than this, the brightness of the image caused by burn-in and the It is possible to further reduce the color difference within a range where there is no discomfort. In addition, the image display position immediately before the image display is turned off is stored for each display mode, and the image is displayed at the previously displayed position when the image signal of the same display mode is input next time. Burn-in is performed by preventing the position from being biased and by moving the image display position after the time obtained by subtracting the duration of image display in the same display mode as immediately before the image display was turned off has elapsed. The inclination of can be made even less noticeable.

[Brief description of drawings]

FIG. 1 is a block diagram of a main part of an embodiment of a video display device according to the present invention.

FIG. 2 is an explanatory diagram of a video display portion and a mask portion.

[Explanation of symbols]

1 Video signal processor 2 Display 3 Display mode detector 4 Display rate detector 5 Display position controller 6 clock section 7 setting section 8 RGB matrix section 9 Video demodulator 10 Y / C separation section 11 Control part 21 Display screen 22 Image display area 23 Mask part 24 boundaries

Claims (8)

[Claims] 1. A video signal processing unit performs predetermined signal processing by a video signal processing unit and sends the video signal to a display unit to display the video on a screen. In the letterbox mode, the video based on the video signal is displayed on the screen of the display unit. A display mode detecting section for detecting whether the video signal is displayed, a display mode, a side panel mode display, or a full mode display mode; a display rate detecting section for detecting a display rate of the video signal; A display position control unit that controls the video display position in the display unit via the video signal processing unit, and a control unit that controls the display mode detection unit, the display ratio detection unit, and the display position control unit, and the display mode detection unit When a display mode other than the full mode display is detected by the display ratio control unit, the same display is performed by the display position control unit based on the display ratio detected by the display ratio detection unit. An image display device in which the image display position of the section is moved. 2. A clock unit is provided, and when the display mode detection unit detects a display mode other than full mode display, the clock unit starts clocking, and when the detection continues for a predetermined time or longer, The video display device according to claim 1, wherein the video display device is moved. 3. The video display device according to claim 1, wherein the video display position on the display unit is moved when the display ratio detected by the display ratio detection unit is zero (black image). 4. The video display device according to claim 1, wherein the video display position on the display unit is moved when the display ratio detected by the display ratio detection unit is equal to or lower than a predetermined display ratio. 5. The display ratio detecting unit detects the display ratio of the peripheral part of the image by the video signal, and the display ratio of the peripheral part of the image detected by the display ratio detecting unit is zero or a predetermined display. The video display device according to claim 1 or 2, wherein the video display position on the display unit is moved when the ratio is less than or equal to the ratio. 6. A setting unit for setting a display ratio as a reference when moving the video display position is provided, and the display ratio detected by the display ratio detecting unit is equal to or less than the display ratio set by the setting unit. 6. The image display device according to claim 4, wherein the image display position on the display unit is moved. 7. The display position control section stores the image display position immediately before the image display is turned off for each display mode for each display mode other than the full mode, and the input image is displayed when the image display is turned on next time. The display modes are arranged so that they are respectively displayed at the previously displayed positions according to display modes.
5. The image display device according to 5 or 6. 8. The display position control unit stores the duration of image display at the image display position immediately before the image display is turned off, and the next time the image display is turned on, the last time of the previous image in the display mode is stored. The image display device according to claim 7, wherein the first image display position is moved after the time obtained by subtracting the duration time has elapsed.