JP3531585B2 - 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 a video signal display device for automatically performing optimum video adjustment.

[0002]

2. Description of the Related Art Conventionally, as a video display device in a video signal display device, the one described in JP-A-11-328360 is known. FIG. 6 shows a conventional image display device, which is composed of a phase difference detection circuit 1, an A / D converter 2, a clock generation section 3 and a control section 4.

[0003]

However, in this conventional image display device described above, only a very limited image adjustment is performed to match the phase of the clock of the A / D converter. Automatic image adjustment across the screen is required. The present invention, when the signal generating device which is the signal source of the image display device is changed, provides the optimum contrast, brightness, gain to be given to the image signal before entering the A / D converter, filter characteristics, etc. for the signal generating device. The purpose is to automatically set the image adjustment value.

[0004]

In order to solve this problem, the present invention relates to a video display device such as a liquid crystal display, and when a signal of the video display device or a device as a signal source is changed, an optimum video image is displayed. The adjustment value is automatically set.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is a video display device for automatically setting optimum contrast adjustment values, brightness adjustment values, and filter coefficients according to a device that generates an analog video signal. Display the result of cumulative addition of the absolute value of the difference value between the adjacent pixels of the display pixel of the video signal.
Difference accumulator and output of the difference accumulator and adder
Compare with the addition result of multiple devices already stored,
Signal device identifying means for identifying a device that is a video signal source,
Based on the output of the signal device identification means,
The video display device has a determination means for determining the optimum contrast adjustment value, brightness adjustment value, and filter coefficient for each device, and cumulatively adds the absolute values of the adjacent pixel difference values of the display pixels of the video signal. From the result, it is possible to identify the device that is the video signal source, which has the effect of automatically performing the optimum video adjustment for different video signal devices.

According to a second aspect of the present invention, an A / D converter for converting a video signal output from an analog signal device into a digital video signal, a filter circuit for filtering the digital video signal, and the digital video signal are provided. A contrast adjustment circuit for performing contrast adjustment, a brightness adjustment circuit for performing brightness adjustment on the digital video signal, a filter circuit, the contrast adjustment circuit, and a digital video signal output via the brightness adjustment circuit are displayed. A video display device comprising display means, wherein a difference cumulative adder for cumulatively adding absolute values of adjacent pixel difference values of the digital video signal, and a result output from the difference cumulative adder are already stored. There are multiple
Signal device specifying means for specifying the device which is the video signal source by comparing the addition result of the device, and the brightness adjustment value given to the brightness adjusting circuit by the microcomputer from the output result from the signal device specifying means. Brightness adjustment value determining means, a contrast adjustment value determining means for determining a contrast adjustment value given to the contrast adjusting circuit from the output result from the signal device specifying means, and the filter circuit from the output result from the signal device specifying means And a filter coefficient deciding means for deciding a coefficient to be given to the digital display device, wherein the difference cumulative adder cumulatively adds the absolute values of the adjacent pixel difference values of the digital video signal, and the difference Signal device identification that identifies the device that is the video signal source from the result output from the cumulative adder Stage, brightness adjustment value determining means for determining a brightness adjustment value to be given to the brightness adjustment circuit from the output result from the signal device specifying means, and contrast adjustment given to the contrast adjustment circuit from the output result from the signal device specifying means. A video display device comprising: a contrast adjustment value determining means for determining a value; and a filter coefficient determining means for determining a coefficient to be given to the filter circuit based on an output result from the signal device identifying means. Yes, from the result of cumulatively adding the absolute value of the adjacent pixel difference value of the display pixel of the video signal,
Since the device that is the video signal source can be specified, it has an effect that the optimum video adjustment can be automatically performed for different video signal devices.

The invention according to claim 3 is such that an input
An A / D converter for converting a log video signal into a digital video signal, and small when the peak value detection result of the display pixel within the past fixed time of the digital video signal is larger than a predetermined value.
The time constant is large, the small time is large, and the A / D
What is claimed is: 1. A video display device comprising a gain determining means for automatically adjusting an amplifier in front of a converter to an optimum gain , comprising:
Cumulative addition of absolute values of adjacent pixel difference values of digital video signals
Output from the difference cumulative adder
Results and the addition results of multiple devices already stored
Signal that identifies the device that is the video signal source by comparing
A device specifying unit , a result of the device specified by the signal device specifying unit, a gain storage unit that stores the gain determined by the gain determining unit in association with each other, a result of the device specified by the signal device specifying unit, and A peak value of a display pixel of an input video signal is provided, which is provided with a gain selection means for selecting an initial gain value to be given to the amplifier from the gain stored in the gain storage means. Since the optimum gain can be determined for the analog signal before entering the A / D converter based on the detection result, the gain can be automatically optimized. Further, since the optimum gain for the device that generates the analog video signal is stored, the optimum gain can be selected at the moment when the device changes.

[0008]

[0009]

[0010]

The embodiment of the present invention will be described below with reference to FIG.
It will be described with reference to FIG.

<First Embodiment> FIG. 1 shows a configuration for identifying a device from an input signal and performing automatic image adjustment. In FIG. 1, 1 is an analog signal device, 2 is an A / D converter, and 3 is an analog signal device.
Is a display pixel difference cumulative adder, 4 is a microcomputer, 5 is a signal source device specifying means, 6 is a brightness adjustment value determining means, 7 is a contrast adjustment value determining means, 8 is a filter coefficient determining means, 9 is a filter circuit, Reference numeral 10 is a contrast adjustment circuit, 11 is a brightness adjustment circuit, and 12 is a display means for displaying a video signal. FIG. 2 is a diagram showing a means for identifying a signal device from accumulated difference of display pixels.

The video signal output from the analog signal device 1 passes through the A / D converter 2, and the output digital video signal is input to the difference cumulative adder 3. The addition result of the difference cumulative adder 3 is sent to the signal device identifying means 5. As shown in FIG. 2, the result of addition by the differential cumulative adder 3 of the analog signal device 1 currently displayed is compared with the result of addition of a plurality of analog signal devices already stored in the signal device identifying means 5, and the signal source is compared. Identify the device that is. The brightness adjustment value determining unit 6, the contrast adjustment value determining unit 7, and the filter coefficient determining unit 8 determine the filter coefficient, the contrast adjustment value, and the brightness adjustment value from the identification result of the device as the signal source, and the filter circuit 9 and the contrast adjustment circuit. 10,
The brightness adjustment circuit 11 sets the image adjustment value. Here, 4 is a microcomputer, but it goes without saying that it can also be configured by a circuit.

With the above configuration, optimum image adjustment for signal equipment can be automatically performed.

<Embodiment 2> FIG.
3 shows a configuration for giving an optimum gain to an analog signal before entering a D converter, and in FIG. 3, 13 is an amplifier for giving a gain to an analog signal before entering an A / D converter, 1
4 is a peak value detector for detecting the maximum value of the display pixel, 15
Is a time constant adding means for adding a specific time constant to the result output from the peak value detector, and 16 is a time constant adding means 1
The gain determining means 16 determines the gain to be given to the signal before entering the A / D converter according to the peak value detection result to which the time constant is added by 5. FIG. 4 is a diagram showing means for determining the gain to be given to the signal before entering the A / D converter, based on the peak value detection result output from the peak value detector.

The same components as those of the above-described embodiment are designated by the same reference numerals and the description thereof will be omitted.

The analog signal output from the analog signal device 1 passes through the amplifier 13 and the A / D converter 2 and is converted into a digital video signal. The peak value in the display area of the converted digital video signal is detected by the peak value detector 14, and the time constant adding means 15 adds a time constant to the peak value. The gain of the peak value to which the time constant is added is determined by the gain determining means 16 as shown in FIG. Here, when the peak value detection result is smaller than the A / D range, the time constant adding means 15 determines not the optimum gain for the currently displayed signal but the optimum gain for the signal device. For example, a large value of 1 day or more is set as the time constant. Also, when the peak value detection result is the same as the maximum value of the A / D range, there is a possibility that white spots have occurred, and the correct peak value detection result of the input signal cannot be obtained. Therefore, in the above case, adaptive appropriate control for reducing the gain with a small time constant is performed. Here, the time constant is written as small, but a small value such as 1 second or less is set.

With the above configuration, the optimum gain adjustment for the analog signal equipment can be automatically performed.

<Third Embodiment> FIG. 5 shows a configuration of a gain initial value determining means for an analog signal device. In FIG. 5, 17 is a storage device for storing an optimum gain for the analog signal device, and 18 is an analog signal device. It is composed of selection means for selecting an optimum gain. In addition,
The same components as those in the above-described embodiment are designated by the same reference numerals and the description thereof will be omitted.

The storage means 17 stores the kind of signal equipment obtained from the signal equipment specifying means described with reference to FIGS. 1 and 2 and the optimum gain for the analog signal equipment described with reference to FIGS. 3 and 4. The adjustment values are stored in association with each other. Therefore, the gain storage means 17 stores the optimum gain of the analog signal device which has been shown even once in the past. When a device that has been projected even once in the past is used next time, the device is specified from the signal device specifying means, and the optimum gain initial value is selected from the device specifying result and the storing means 17 in the gain selecting means 18. Then, the amplifier 13 is set.

With the above configuration, the optimum initial value of gain for analog signal equipment can be set.

[0022]

As described above, according to the present invention, when the device which is the video signal source in the video display device is changed,
The effect that the optimum contrast adjustment value, brightness adjustment value, filter coefficient, and gain can be automatically set without human judgment is obtained.

[Brief description of drawings]

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

FIG. 2 is a diagram illustrating an operation of identifying a signal device from accumulated difference of display pixels of the video display device.

FIG. 3 is a configuration diagram of a video display device according to an embodiment of the present invention.

FIG. 4 is a diagram showing characteristics of the video display device.

FIG. 5 is a configuration diagram of a video display device according to an embodiment of the present invention.

FIG. 6 is a diagram showing a configuration of a conventional image adjusting device.

[Explanation of symbols]

1 analog signal 2 A / D converter 3 Difference cumulative adder 4 microcomputer 5 Signal equipment identification means 6 Brightness adjustment value determination means 7 Contrast adjustment value determination means 8 Filter coefficient determining means 9 Filter circuit 10 Contrast adjustment circuit 11 Brightness adjustment circuit 12 Display means 13 amp 14 Peak detector 15 Time constant addition means 16 Gain determining means 17 Optimal gain storage means for analog signal equipment 18 Optimal gain selection means for analog signal equipment

─────────────────────────────────────────────────── ─── Continuation of the front page (56) Reference JP-A-58-154982 (JP, A) JP-A-8-279929 (JP, A) (58) Fields investigated (Int.Cl. ⁷ , DB name) H04N 5/14-5/217 H04N 5/50-5/63 H04N 5/66-5/74 G09G 5/00

Claims (3)

(57) [Claims] 1. A video display device for automatically setting an optimum contrast adjustment value, brightness adjustment value, and filter coefficient according to a device that generates an analog video signal, the absolute value of a difference value between adjacent pixels of display pixels of the video signal. A differential cumulative adder for outputting a result of cumulative addition of values, and the differential cumulative addition
The output of the instrument and the addition results of multiple devices that are already stored
By comparison, the signal device feature that identifies the device that is the video signal source.
And a microphone based on the output of the signal device specifying means.
(B) The computer has an optimal contrast adjustment value for each device ,
An image display device comprising: a determining unit that determines a brightness adjustment value and a filter coefficient. 2. An A / D converter for converting a video signal output from an analog signal device into a digital video signal, a filter circuit for filtering the digital video signal, and a contrast for performing contrast adjustment on the digital video signal. An image including an adjusting circuit, a brightness adjusting circuit for adjusting the brightness of the digital image signal, the filter circuit, the contrast adjusting circuit, and a display unit for displaying the digital image signal output through the brightness adjusting circuit. A display device, wherein a difference cumulative adder for cumulatively adding the absolute values of adjacent pixel difference values of the digital video signal, a result output from the difference cumulative adder, and an addition result of a plurality of devices already stored And ratio
A signal device specifying unit that specifies a device that is a video signal source by comparing, and a brightness adjustment value determining unit that determines a brightness adjustment value provided by the microcomputer to the brightness adjusting circuit from the output result from the signal device specifying unit. A contrast adjustment value determining means for determining a contrast adjustment value to be given to the contrast adjusting circuit based on an output result from the signal device specifying means, and a filter for determining a coefficient to be given to the filter circuit from an output result from the signal device specifying means An image display device comprising: a coefficient determining means. 3. The input analog video signal is digital
A / D converter for converting into a video signal, and a small time constant when the peak value detection result of the display pixel in the past fixed time of the digital video signal is larger than a predetermined value , and a small time constant
Is a large time constant, and is provided with a gain determining means for automatically adjusting the amplifier in front of the A / D converter to an optimum gain.
A video display device adjacent to the digital video signal.
A cumulative difference adder for cumulatively adding absolute values of pixel difference values,
The result output from the difference cumulative adder has already been stored
By comparing the addition results of multiple devices,
Signal device specifying means for specifying a device as a signal source, a result of the device specified by the signal device specifying means, and a gain storage means for storing the gain determined by the gain determining means in association with each other, and the signal device specifying means. An image display device, comprising: the result of the device specified by the above, and a gain selection unit that selects an initial gain value to be given to the amplifier from the gain stored in the gain storage unit.