JPH10304275A - Television receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce doming resulting from a luminance difference between a major image plane and a sub image plane in the case of 2-screen display. SOLUTION: APL detection circuits 8, 9 detect an average luminance level (APL) of video signals of a major image plane and a sub image plane in the case of 2-screen display, and a difference or absolute value of difference detection circuit 10 detects an absolute value of a difference of both the APLs. A control circuit 11, according to the absolute value of the difference, controls a luminance of a synthesized video signal of the major image plane and the sub image plane synthesized by a synthesis pattern video adjustment circuit 4 to reduce doming in the case of 2-screen display.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver (International Patent Classification H04N 5/45) having a function of displaying a plurality of different video signals on one screen.

[0002]

2. Description of the Related Art In recent years, with the spread of wide-screen television receivers having an aspect ratio of 16: 9, the number of television receivers having a function of displaying a plurality of different video signals on one screen has increased rapidly. I have. For example, one having the display function is described in Japanese Patent Application Laid-Open No. 7-298157. In recent years, in a television receiver having this function, 2
In some cases, when the screen function is performed, the contrast, ACL, and ABL are controlled so as to eliminate the difference in accordance with the luminance difference between the video signal serving as the main screen and the video signal of the two screens.

[0003]

As described above, when two different video signals are displayed in one screen, the contrast and the ACL are determined according to the luminance difference between the video signal serving as the main screen and the video signal in the two screens. , ABL and the like. However, if one of the two screen video signals is bright and the other is dark, the luminance difference between the main screen video signal and the two screen video signal becomes large, and ACL increases the luminance level of the entire screen. Because of the control in the direction, a bright image portion on the screen often has a possibility of causing the doming. Further, even when the vertical amplitude of the video signal in the two screens is displayed while being compressed, the beam amount per unit area in the screen increases, so that doming is more likely to occur.

[0004]

In order to solve the above-mentioned problems, a television receiver according to the present invention employs a main screen for reducing doming when a luminance difference between a main screen and a sub-screen in two screens is large. Between video signal of sub-screen and video signal of sub-screen
L is detected, and the contrast, ACL, ABL, and the like of the video signal for two screens are controlled in accordance with the absolute value of the difference between these values.

According to the present invention, there is provided a television receiver which can reduce doming on a screen even when a luminance difference between a video signal on a main screen and a video signal on a sub-screen is large during two-screen display. is there.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS A television receiver according to claim 1 of the present invention displays two different video signals on one screen, or displays a video signal by compressing the vertical amplitude of the video signal. In accordance with the luminance difference between the video signal serving as the main screen and the video signal at the time of the two screens, the contrast, ACL, ABL, etc. of the video signal at the time of the two screens are controlled so as to compensate for the difference. It is possible to reduce the doming at the time of the screen.

A television receiver according to a second aspect of the present invention detects an APL of a video signal between a main screen and a sub-screen when a two-screen display is performed, and calculates an absolute value of a difference between the values. It is characterized by doing. This makes it possible to quantitatively detect the statistical properties of the video signal, and control contrast, ACL, and ABL using this value to reduce doming during two screens.

A television receiver according to a third aspect of the present invention detects an APL of a video signal between a main screen and a sub-screen when a two-screen display is performed, and calculates an absolute value of a difference between the values. The contrast of the video signal for two screens is controlled in accordance with this value. The contrast controls the amplitude level of the video signal, and since the brightness of the video signal changes by controlling the amplitude level, the doming is performed by controlling the amplitude level of the video signal in two screens according to this value. Can be reduced.

According to a fourth aspect of the present invention, a television receiver detects an APL of a video signal between a main screen and a sub-screen when a two-screen display is performed, and determines the APL according to the absolute value of the difference. It controls the ACL of the video signal at the time of the screen. ACL
Is to detect the amount of beam and control the luminance of the video signal so that the beam amount becomes a certain value, thereby reducing the doming.

A television receiver according to a fifth aspect of the present invention detects an APL between a video signal of a main screen and a video signal of a sub-screen when a two-screen display is performed, and detects an absolute value of a difference between the values. Is calculated, and the AB of the video signal at the time of two screens is
L is also controlled. The ABL detects a change in the current of the flyback transformer and controls the beam amount.
AB according to the difference between the APLs of the video signals of the main screen and the sub-screen
By controlling L, the beam amount of the video signal in two screens can be quantitatively controlled, so that the doming in two screens can be reduced.

In the television receiver according to the sixth aspect of the present invention, when a two-screen display is performed, the APL of the video signal between the main screen and the sub-screen is detected. It is characterized by controlling the contrast or ACL of the screen or sub-screen. The difference value of the APL between the video signal of the main screen and the video signal of the sub-screen is controlled by controlling the contrast, ACL, ABL, etc. of the main screen if the main screen is large, and the sub-screen if the sub-screen is large. It is possible to reduce the doming by controlling the luminance difference between the main screen and the sub-screen in two screens.

In the television receiver according to the present invention, when a two-screen display is performed, a luminance level A of a video signal serving as a main screen and a luminance level B of a video signal serving as a sub-screen are detected. Then, the luminance level A of the main screen video signal is compared with the luminance level B of the sub-screen video signal, and the H level is output from the comparison circuit when A> B, and the H level is output when A <B. Next, based on these output levels, the brightness of the sub-screen is controlled by a value divided by a resistance circuit formed of a resistor connected in parallel and in series with the switch. The brightness difference can be controlled to reduce doming.

[0013] The invention according to claim 8 of the present invention provides an ABL
The voltage C is input, compared with a certain set value D, and when C> D, the H level is output from the comparison circuit. When the output from the comparison circuit is at the H level, the comparison circuit for comparing the brightness of the main screen and the sub-screen outputs a fixed value for both the main and sub-screens, and keeps the division resistance ratio constant. 7. The television receiver according to claim 6, wherein an operation of turning off the luminance comparison between the two screens when the ABL voltage is larger than the threshold value is provided.

According to a ninth aspect of the present invention, a display signal for a main screen which is at an H level in a region other than a display range of a video signal for a main screen is integrated, and a luminance level of the video signal which is a main screen is obtained. The multiplied value A is integrated with the display signal to be the H-level sub-screen outside the display range of the luminance signal to be the sub-screen, and the value B is calculated by multiplying by the luminance level of the video signal of the sub-screen. It is characterized by doing. As a result, it is possible to perform luminance comparison irrespective of the display area of an image, and it is possible to reduce doming during two-screen compression display.

According to a tenth aspect of the present invention, there is provided a television receiver having a non-interlaced scanning and having a two-screen display function. APL is detected, the absolute value of the difference between the values is calculated, and the luminance of the interpolated line of the video signal for two screens is controlled according to the value. As a result, it is possible to reduce doming when displaying two screens in non-interlace scanning.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG. In the embodiments, the same reference numerals are used for the same components, and the description is omitted.

(Embodiment 1) In FIG. 1, 1 is a main screen signal processing circuit, 2 is a sub screen signal processing circuit, 3 is a main / sub switching circuit, 4 is a composite screen video adjustment circuit, and 5 and 6 are luminance. The detection circuit 7 is a brightness control circuit. The video signals of the main screen and the sub-screen are converted into a main screen signal processing circuit 1 and a sub-screen signal processing circuit 2
Respectively. The brightness of the main screen video signal is APL
The detection is performed by the detection circuit 8. The video signals of the main screen and the sub-screen pass through the main / sub switching circuit 3 and are synthesized and output by the synthesized screen video adjustment circuit 4. The luminance of the video signal synthesized by the composite screen video adjustment circuit 4 is detected by the luminance detection circuit 6, and the luminance control circuit 7 compares the luminance of the main screen with the luminance of the composite screen. , It is possible to reduce doming in two screens.

(Embodiment 2) In FIG. 2, reference numerals 8 and 9 denote APL detection circuits for the main screen and sub-screen, 10 denotes an absolute value detection circuit for the difference, and 11 denotes a control circuit. The video signals of the main screen and the sub-screen are the main screen signal processing circuit 1 and the sub-screen signal processing circuit 2
Are passed through the main / sub switching circuit 3 to be combined by the combined screen image adjustment circuit 4. The APL detection circuits 8 and 9 detect the APLs of the main screen and the sub-screen, and the absolute value difference detection circuit 10 detects the absolute value of the difference between the two, and the control circuit 1
1 is input. The control circuit 11 controls the luminance of the video signal synthesized by the synthesized screen video adjustment circuit 4 in accordance with the absolute value of the APL difference detected by the difference absolute value detection circuit 10 to reduce doming. Become.

(Embodiment 3) In FIG. 3, reference numeral 12 denotes a contrast control circuit. The video signals of the main screen and the sub-screen are input to the main screen signal processing circuit 1 and the sub-screen signal processing circuit 2, and are synthesized by the synthesized screen video adjustment circuit 4 through the main / sub switching circuit 3. The APLs of the main screen and the sub-screen are detected by the APL detection circuits 8 and 9, and the absolute value of the difference between the two is detected by the absolute value detection circuit 10 of the difference and input to the contrast control circuit 12. In the contrast control circuit 12, the 2 synthesized by the synthesized screen image adjustment circuit 4 according to this value
It is possible to control the contrast of the screen image and reduce doming.

(Embodiment 4) In FIG.
This is a CL control circuit. Video signals of the main screen and the sub-screen are input to the main screen signal processing circuit 1 and the sub-screen signal processing circuit 2,
Both are combined by the combined screen image adjustment circuit 4 through the main / sub switching circuit 3. The APLs of the main screen and the sub-screen are detected by the APL detection circuits 8 and 9, and the absolute value of the difference between the two is detected by the absolute value detection circuit 10 of the difference and input to the ACL control circuit 13. The ACL control circuit 13 controls the ACL of the two screen images synthesized by the synthesized screen image adjustment circuit 4 according to this value, and can reduce the doming.

(Embodiment 5) In FIG.
This is a BL control circuit. Video signals of the main screen and the sub-screen are input to the main screen signal processing circuit 1 and the sub-screen signal processing circuit 2,
Both are combined by the combined screen image adjustment circuit 4 through the main / sub switching circuit 3. The APLs of the main screen and the sub-screen are detected by the APL detection circuits 8 and 9, and the absolute value of the difference between the two is detected by the absolute value detection circuit 10 of the difference and input to the ACL control circuit 13. The ABL control circuit 14 controls the ACL of the two screen images synthesized by the synthesized screen image adjustment circuit 4 according to this value, thereby making it possible to reduce the doming in the two screens.

(Embodiment 6) In FIG. 6, 15 is a control circuit, 16 is a switch circuit, and 17 and 18 are video adjustment circuits for the main screen and the sub-screen. The video signals of the main screen and the sub-screen are input to the main screen signal processing circuit 1 and the sub-screen signal processing circuit 2 through the main screen and sub-screen video adjustment circuits 17 and 18, and are adjusted through the main / sub switching circuit 3. Circuit 4
The two are combined. The APL detection circuits 8 and 9 detect the APL of the main screen and the sub-screen, and detect the absolute value of the difference 1
At 0, the difference between the two is detected and input to the control circuit 15.
The control circuit 15 detects the magnitude relationship between the values, and outputs a switch control signal and a luminance control signal to the switch circuit 16 according to the value. Thus, by controlling the brightness on the main screen side or the sub-screen side according to the difference value of the APL, it is possible to reduce doming in two screens.

(Embodiment 7) In FIG. 7, 19 is a luminance signal comparison circuit, and 20 to 25 are sub-screen control signal generation voltage dividing circuits. The luminances of the main screen and the sub-screen are detected by the luminance detection circuits 5 and 6, respectively, and compared by the comparison circuit 20, and the output of the sub-screen image adjustment circuit 18 is controlled by controlling the voltage dividing ratio of the resistor according to the comparison result. Is done. As shown in FIG. 11, the brightness of the sub-screen is controlled with respect to the main screen. According to such a configuration, in a two-screen television, the brightness of the main screen and the brightness of the sub-screen are compared, and the screen is corrected in accordance with the difference in brightness, so that the brightness of the screen can be optimized. Doming can be reduced.

(Embodiment 8) In FIG.
7 is a luminance comparison control switch, and 28 is an ABL comparison circuit. In addition to the seventh embodiment, the comparison circuit 28 compares the ABL voltage C with a certain threshold value, and controls the luminance comparison by using the switches 26 and 27 controlled by the output of the comparison circuit 28. According to such a configuration, when the ABL voltage is higher than the threshold value, the luminance comparison between the two screens can be turned off.

(Embodiment 9) Referring to FIG.
0 is an integration circuit, and 31 and 32 are multiplication circuits. In addition to the eighth embodiment, by using integration circuits 29 and 30 for integrating the display area of the screen and multiplication circuits 31 and 32 for weighting the luminance detection circuit according to the outputs from the integration circuits 29 and 30, The brightness can be compared regardless of the display area of the screen.

(Embodiment 10) In FIG.
Is a control circuit, and 34 is a composite screen signal processing circuit. The video signals of the main screen and the sub-screen are input to the main screen signal processing circuit 1 and the sub-screen signal processing circuit 2, and are synthesized by the synthesized screen video adjustment circuit 4 through the main / sub switching circuit 3. Next, the video signal converted into the composite screen is subjected to non-interlace scanning processing by the composite screen signal processing circuit 34 and output. The APL detection circuits 8 and 9 detect the APLs of the main screen and the sub-screen, and the absolute value detection circuit 10 detects the absolute value of the difference between the two and inputs it to the control circuit 33. In accordance with this value, the control circuit 33 controls the luminance of the interpolation lines of the two-screen video obtained by performing non-interlaced scanning on the composite screen by the composite-screen signal processing circuit 34, thereby reducing the doming in the two-screen. .

The present invention can be applied to a television receiver having a multi-screen display function of displaying a plurality of video signals in one screen, and the same effect can be obtained. Needless to say.

[0028]

As described above, according to the television receiver of the present invention, the APLs of the video signals of the main screen and the sub-screen at the time of two screens are respectively calculated, and according to the absolute value of the difference,
By controlling the contrast or ACL or ABL of the video signal at the time of two screens, it is possible to reduce doming at the time of two screens, and the difference between the APL of the video signal of the main screen and the APL of the sub-screen at the time of two screens. Contrast, ACL, AB only on main screen side or sub screen side depending on magnitude of value
An object of the present invention is to provide a television receiver capable of reducing doming on two screens by controlling L and the like. Further, in a television receiver having non-interlace scanning and having a two-screen function, the two-screen image is displayed in accordance with the absolute value of the difference between the APLs of the video signals of the main screen and the sub-screen in the two screens. An object of the present invention is to provide a television receiver capable of reducing doming by controlling the luminance of a signal interpolation line.

[Brief description of the drawings]

FIG. 1 is a circuit configuration diagram of a television receiver according to Embodiment 1 of the present invention.

FIG. 2 is a circuit configuration diagram of a television receiver according to Embodiment 2 of the present invention.

FIG. 3 is a circuit configuration diagram of a television receiver according to Embodiment 3 of the present invention.

FIG. 4 is a circuit configuration diagram of a television receiver according to a fourth embodiment of the present invention.

FIG. 5 is a circuit configuration diagram of a television receiver according to a fifth embodiment of the present invention.

FIG. 6 is a circuit configuration diagram of a television receiver according to a sixth embodiment of the present invention.

FIG. 7 is a circuit configuration diagram of a television receiver according to a seventh embodiment of the present invention.

FIG. 8 is a circuit configuration diagram of a television receiver according to an eighth embodiment of the present invention.

FIG. 9 is a circuit configuration diagram of a television receiver according to a ninth embodiment of the present invention.

FIG. 10 is a circuit configuration diagram of a television receiver according to Embodiment 10 of the present invention.

FIG. 11 is a waveform control diagram of a main screen and a sub-screen according to the seventh embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Main screen compression processing circuit 2 Sub-screen compression processing circuit 3 Main / sub switching circuit 4 Synthetic screen image adjustment circuit 5, 6 Brightness detection circuit 7 Brightness control circuit 8, 9 APL detection circuit 10 Difference or absolute value detection circuit of difference 11 Control circuit 12 Contrast control circuit 13 ACL control circuit 14 ABL control circuit 15 Control circuit 16 Switch circuit 17 Main screen video signal adjustment circuit 18 Sub-screen video signal adjustment circuit 19 Brightness signal comparison circuit 20-25 Sub-screen control signal generation voltage dividing resistor 26, 27 brightness comparison control switch 28 ABL comparison circuit 29, 30 integration circuit 31, 32 multiplication circuit 33 control circuit 34 composite screen signal processing circuit

 ──────────────────────────────────────────────────続 き Continued on the front page (72) Inventor Kenichiro Yokoyama 1006 Kazuma Kadoma, Kadoma, Osaka Matsushita Electric Industrial Co., Ltd.

Claims (10)

[Claims] In a television receiver having a two-screen display function, the brightness of a video signal serving as a main screen is compared with the brightness of a video signal serving as a sub-screen, and correction is performed for a screen having a low brightness to thereby improve brightness of the screen. A television receiver characterized by reducing the doming on the screen by optimizing the image quality. 2. When performing two-screen display, an average luminance level (hereinafter referred to as A) of a video signal serving as a main screen and a video signal serving as a sub-screen is displayed.
2. The television receiver according to claim 1, wherein an absolute value of a difference between the detected values is detected. 3. When a two-screen display is performed, an APL of a video signal serving as a main screen and an APL of a video signal serving as a sub-screen are detected, an absolute value of a difference between the values is calculated, and the two screens are calculated according to the value. 3. The television receiver according to claim 2, wherein the contrast of the video signal at the time is controlled. 4. When a two-screen display is performed, an APL of a video signal serving as a main screen and an APL of a video signal serving as a sub-screen are detected, an absolute value of a difference between the values is calculated, and the two screens are calculated according to the value. 3. The television receiver according to claim 2, wherein an automatic amplitude limit (hereinafter, referred to as ACL) of the video signal at the time is controlled. 5. When a two-screen display is performed, an APL of a video signal serving as a main screen and an APL of a video signal serving as a sub-screen is detected, an absolute value of a difference between the values is calculated, and the two screens are calculated according to the value. 3. The television receiver according to claim 2, wherein an automatic luminance limit (hereinafter, referred to as ABL) of the video signal at the time is controlled. 6. When a two-screen display is performed, the APL of a video signal serving as a main screen and an APL of a video signal serving as a sub-screen are detected.
The television receiver according to claim 2, wherein L is controlled. 7. When a two-screen display is performed, a luminance level of a video signal to be a main screen and a luminance level of a video signal to be a sub-screen are detected, and a luminance level of a main screen video signal and a luminance level of a sub-screen video signal are detected. When the luminance level of the sub-screen is high, the output value is composed of resistors connected in parallel and in series with a switch for controlling the output to be H level when the luminance level of the main screen is high. 2. The television receiver according to claim 1, wherein the ABL is controlled by a division ratio between an output value connected in parallel and a series having a switch controlled by an output at H level. 8. A comparison circuit which receives an ABL voltage C, compares it with a certain set value D, and outputs an H level when C> D is added. When the output from the comparison circuit is an H level,
7. The television receiver according to claim 6, wherein the output of each H level of the brightness comparison circuit is fixed to keep the divided resistance ratio constant and keep the voltage constant. 9. A display signal that is an H level outside the display range of a video signal that is a main screen and a display signal that is an H level outside a display range of a luminance signal that is a sub screen. Compare the value obtained by multiplying the integral value of the main screen display signal with the luminance level of the video signal of the main screen, and the value obtained by multiplying the integral value of the display signal forming the sub-screen with the luminance level of the video signal of the sub-screen. The television receiver according to claim 6, wherein: 10. A system having non-interlace scanning, and
When a two-screen display is performed by a television receiver having a screen display function, an APL between a video signal serving as a main screen and a video signal serving as a sub-screen is detected, and an absolute value of a difference between the values is calculated. 3. The television receiver according to claim 2, wherein the luminance of the interpolation line of the video signal at the time of two screens is controlled according to the value.