JP2950251B2 - Image 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 apparatus, and more particularly, to an input image for discriminating a model of a video signal output from various different computers by an automatic frequency tracking function and switching image data based on the discrimination. The present invention relates to an image display device having a signal discriminating function.

[0002]

2. Description of the Related Art In general, for example, video signal systems output from various computers manufactured by different manufacturers are not standardized, but are video signals of different systems (for example, signals having different resolutions). In an image display device such as a cathode ray tube (CRT), a liquid crystal display, or a plasma display, which is capable of displaying video signals output from such various computers, image size correction and image size correction according to the system of the input video signal are performed. It is necessary to perform image distortion correction such as screen position correction.
That is, an image display device capable of displaying video signals output from various different computers requires an “input video signal determination function” for determining what kind of system the input video signal is.

A conventional image display apparatus having the input video signal discriminating function tracks the horizontal frequency and vertical frequency of the input video signal of the image display apparatus and the polarities of the horizontal and vertical synchronizing signals by an automatic frequency tracking function. Therefore, the following features are provided on the assumption that the input video signal is determined and switched based on them.

A first feature is that a concept of a range (discrimination range) for model determination is provided for a horizontal frequency and a vertical frequency. This range is continuous, the range is relatively wide, and any video signal input within the range is determined to be the same video signal.

A second feature is that there is a changeover switch called a mode switch or a memory switch, and the above-described determination range can be multiplexed by turning on / off the changeover switch (for example, The mode can be made different depending on the fixed standard image data and the registered image data that can be registered by the user.)

[0006] Regarding the automatic determination of the model of the input video signal, it is possible to set as many user systems as necessary without being limited by the horizontal frequency of the input video signal, the state of the synchronization signal, and the like. (Japanese Patent Laying-Open No. 4-271395: Title of Invention, "System for Determining System of Input Video Signal of Multiscan Monitor and Multiscan Monitor")
And an image display device which can identify a case where there is an error or variation in the oscillator for counting the horizontal frequency or a new model in which a certain computer is defaulted (Japanese Patent Laid-Open No. 6-161).
No. 415, entitled "Display Device Having Computer Discrimination Function") is also known.

In the image display device described in Japanese Patent Application Laid-Open No. 4-271395, a system in which the horizontal frequency of an input video signal, the number of scanning lines during a vertical period, and the polarity of a synchronization signal are detected, and the detection result is stored in a memory. The system of the input video signal is determined based on the information, the optimum system is determined, and the image distortion is corrected using the optimum image distortion correction data.

Also, in the image display device described in Japanese Patent Application Laid-Open No. 6-161415, the horizontal frequency and the 1
Based on the count result obtained by counting the number of scanning lines in the vertical period by the counter circuit and the result of determining the polarity of the horizontal and vertical synchronization signals of the input video signal, the computer model and the graphic screen or text screen are obtained by fuzzy inference. This is a configuration for specifying whether the

[0009]

However, the conventional image display apparatus having the input video signal discriminating function has a wide range for discriminating the model, and any video signal can be input within the range. Since they are recognized as the same model, there is a possibility that the certainty of the determination is lacking. In addition, since the user needs to operate a changeover switch (such as a mode switch) at the time of mode switching, the operation for determining the model of the input video signal becomes complicated.

Further, in the image display device described in Japanese Patent Application Laid-Open No. 4-271395, since the concept of a range is used for discriminating the system, there is a possibility that the discrimination of the discrimination may be lacked as in the above-described conventional device. . Further, Japanese Unexamined Patent Application Publication No. 6-161
In the image display device described in Japanese Patent Publication No. 415, a specific inference called fuzzy inference is used in order to make it impossible to distinguish an indistinguishable graphic screen and a text screen within the same range. There is.

The present invention has been made in view of the above points,
It is an object of the present invention to provide an image display device capable of determining a more accurate input video signal or a computer model.

It is another object of the present invention to provide an image display device which can eliminate the troublesome operation for the determination.

[0013]

In order to achieve the above object, the present invention provides an input signal detecting section for detecting a horizontal frequency and a vertical frequency of an input video signal, and a polarity of a horizontal synchronizing signal and a vertical synchronizing signal. A model discriminating unit for discriminating a model of the video device outputting the input video signal based on a detection result detected by the signal detection unit; and a vertical cycle based on the detection result detected by the input signal detection unit. Resolution determining means for calculating the number of horizontal lines and determining the resolution of the video equipment outputting the input video signal from the number of horizontal lines, and the model determined by the model determining means and the resolution determined by the resolution determining means To determine if the model and the resolution match, and if so, determine the model determined by the model determination means as the final video device model, If not, the apparatus further comprises a discriminating / comparing means for newly determining a model of the video device outputting the input video signal based on the number of horizontal lines per vertical cycle and the detected vertical frequency. The information is automatically set to the information and the image is displayed.

Here, the model discriminating means of the present invention comprises a first discriminating table in which the horizontal frequency and the vertical frequency, the polarity and the resolution of each of the horizontal and vertical synchronizing signals are summarized for each of a plurality of models. The resolution determination means determines the resolution by referring to the calculated number of horizontal lines in a second determination table in which the resolution and the range of the number of horizontal lines are compiled in correspondence with each other. When the determined model and the resolution do not match, the means newly determines a model corresponding to the detected vertical frequency by referring to the first determination table based on the determined resolution.

According to the present invention, when determining the type of the video equipment which is the video signal source outputting the input video signal, the resolution is determined within the same range determined from the horizontal frequency, the vertical frequency and the polarity of the synchronization signal. Since the model is also determined, and when the two are different, the model is determined based on the resolution and the vertical frequency. Therefore, it is possible to prevent the setting of a model that is impossible with the resolution.

[0016]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of an image display device according to the present invention. This embodiment is constituted by a read only memory (ROM).
A standard image data storage unit 1 in which standard image data necessary for displaying an image of a plurality of models to be determined, such as resolution and image size correction, are stored in advance. A registered image data storage unit configured by an EEPROM and storing registered image data such as position correction information of an arbitrary screen registered by a user for at least one of a plurality of models to be determined. 2, a control unit 3, which is an input device for controlling adjustment and operation,
An input signal detector 7 for detecting the state of an input signal, and a central processing unit (CPU) 1 for determining the type of a computer
1 and an image data adjustment unit 1 for setting image data
2 and an image display unit 13 for displaying a video with a resolution and an image size set by the image data set by the image data adjustment unit 12.

The input signal detector 7 includes a horizontal frequency detector 4 for detecting the horizontal frequency of the input video signal, a vertical frequency detector 5 for detecting the vertical frequency, and a synchronization polarity detector 7 for detecting the polarities of the horizontal and vertical synchronization signals. Consists of The central processing unit (CPU) 11 also includes a first determination unit 8 for determining a model based on the horizontal frequency, the vertical frequency, and the polarity of each of the horizontal and vertical synchronization signals.
The second discriminator 9 for calculating the number of horizontal lines per cycle and discriminating the resolution from the number of horizontal lines per one vertical cycle, the model and resolution determined by the first discriminator 8 and the second discriminator 9 , A discriminating / comparing unit 10 for discriminating the model of the computer that finally outputs the video signal and setting the image data.

Next, the operation of this embodiment will be described in detail with reference to FIG. 2, FIG. 3, FIG. 4, FIG. 5, and FIG. In FIG. 1, a composite synchronizing signal in a video signal output from a computer (not shown) is input to an input signal detecting unit 7, where the horizontal frequency, vertical frequency, and the polarities of both horizontal and vertical synchronizing signals are detected. You. These detection results are input to the CPU 11, and are processed by the first determination unit 8, the second determination unit 9, and the determination comparison unit 10 in the CPU 11.

FIG. 2 is a flowchart for explaining the operation of the first discriminating unit 8 in the CPU 11 as a main part of the present invention. In the figure, the first determination unit 8 performs a horizontal frequency determination process of an input video signal (Step 201), and then performs a process of determining a vertical frequency based on the result (Step 202). Thereafter, a process of determining the polarity of each of the horizontal and vertical synchronization signals is performed (step 203), and the model Xn is determined based on the above determination result (step 204).

As described above, the first determination unit 8 determines the type of the computer outputting the input video signal based on the horizontal frequency and the vertical frequency of the input video signal and the polarities of the horizontal and vertical synchronization signals. . For a series of operations of the first determination unit 8, refer to the schematic diagram of the determination table shown in FIG. 5 showing the horizontal frequency, the vertical frequency, and the polarities of both horizontal and vertical synchronization signals for determining the type of the typical computer. It was processed. In FIG. 5, the mode indicates the resolution, and the parentheses indicate the vertical frequency.

FIG. 3 is a flowchart for explaining the operation of the second discriminating unit 9 in the CPU 11 as a main part of the present invention. In the figure, the second determination unit 9 calculates the number of horizontal lines per vertical cycle (the number of lines per vertical cycle = horizontal frequency / vertical frequency) (step 301), and based on the calculation result, sets conditions. A process of determining a resolution to be satisfied is performed (step 302), and finally, a resolution group Ym in the second determination unit 9 is determined (step 303).

In this way, the second determination section 9 determines the resolution of the computer that is outputting the input video signal. A series of operations of the second determination unit 9 are shown in FIG. 6 in a table showing the number of horizontal lines per vertical cycle for determining the resolution of the computer used in the embodiment of the image display device of the present invention. It has been processed with reference to the schematic diagram.

FIG. 4 is a flow chart for explaining the operation of the discrimination / comparison unit 10 in the CPU 11 as a main part of the present invention. In the figure, the discrimination comparing section 10 includes a model Xn determined by the first discriminating section 8 and a second discriminating section 9 in order to make a discrimination for finally determining the model of the computer outputting the video signal. It is determined whether or not the resolution Xm includes the model Xn on the basis of the resolution Ym determined in Step (40).
1) If the resolution Xm includes the model Xn, the model Xn is determined as the final computer model Z1 (step 402).

If the resolution Ym does not include the model Xn, a determination process is performed based on the number of horizontal lines per vertical cycle and the vertical frequency based on the resolution Ym (step 403). (Step 40)
4). When the model Z1 of the final computer is determined, data corresponding to the model Z1 is read from the standard image data storage unit 1 or the registered image data storage unit 2 and set in the image data adjustment unit 12 (step 405). .

The image data set by the image data adjustment unit 12 is supplied to the image display unit 13 and the number of lines to be displayed on the image display unit 13 so that an image of the determined model can be displayed at a resolution determined by the model. And the number of dots. When this condition setting is completed, a video signal from the computer is input to the image display unit 13 via a path (not shown) and displayed as an image at an optimum resolution that should be originally displayed at an original or user-set image size and position. Is done.

As described above, the CPU 11 performs the model determination by the first determination unit 8, the resolution determination by the second determination unit 9, and the final model determination of the computer by the determination comparison unit 10. Different resolutions within the same range can be determined, and settings can be made according to the resolution.

[0028]

Next, an embodiment of the present invention will be described.
As an embodiment of the present invention, the horizontal frequency fH = 45 kHz,
A determination operation for a computer that outputs a video signal with a vertical frequency fV = 75 Hz and a resolution of 640 × 480 will be described. In the first discriminating unit 8, since the horizontal frequency fH of the input video signal is 45 kHz from the discriminant table shown in FIG. 5, in the horizontal frequency discriminating process of the input video signal in step 201 by the first discriminating unit 8, 43 kHz ≦ fH <4
The frequency range is 7.2 kHz.

Subsequently, step 20 by the first discriminating unit 8
In the vertical frequency discriminating process of the input video signal in Step 2, the horizontal frequency range 43 kHz ≦ fH <based on the first discrimination table shown in FIG. 5 based on the detection result that the vertical frequency fV of the input video signal is 75 Hz. The range of fV <80 Hz at 47.2 kHz is determined, whereby the model Xn is determined to be the model number 12 and its mode (resolution)
Is 800 × 600 from the discrimination table. However, the mode of the model of the model number 12 determined here is obviously different from that of the input video signal, ie, 640 × 480.

Next, in the second discriminating section 9, the horizontal frequency fH
= 45 kHz and vertical frequency fV = 75 Hz, the number of horizontal lines per vertical cycle is 600 (= 45000/7).
5) It is calculated that the line is a line, and referring to the second discrimination table shown in FIG. 6 based on the calculation result, since the number of lines is less than 602 lines and more than 480 lines, the resolution Ym is 640 × 4
It is determined to be 80 dots. Resolution Ym determined here
It can be seen that the same as the resolution of the input video signal 640 × 480 was obtained.

Further, as shown in step 401 in FIG. 4, the discrimination comparison section 10 determines the resolution of the model of the model number 12 determined by the first determination section 8 and the resolution Ym determined by the second determination section 9. 640 × 480 dots are compared with each other, and it is determined whether or not there is a model Xn (model of model number 12) having the resolution Ym. Here, the resolution of the model Xn (model of model number 12) is 800 × 600 as shown in FIG. 5 and is different from 640 × 480 of the resolution Ym. And a new model is determined from the vertical frequency.

At this time, information of the resolution Ym that the resolution is 640 × 480 from 600 horizontal lines per vertical cycle, and the vertical frequency fV of the input video signal
Is determined with reference to the first determination table in FIG. 5 based on the information that the vertical frequency is 75 Hz, the vertical frequency fV of 75 Hz is 8 Hz at 73 Hz or higher in the resolution of 640 × 480.
Since the frequency is less than 0 Hz, the mode of the computer model Z1 that outputs the final determined video signal is 640 × 480.
Is determined as model number 9.

The image data is read from the standard image data storage unit 1 or the registered image data storage unit 2 based on the finally determined computer model Z1, and the image data adjustment unit 12 is set.

By performing these series of determination operations,
In the related art, although the resolutions are different, those that have been determined to be the same model can now determine the correct model by determining the resolution. Further, by including the determination based on the resolution in addition to the conventional method, a more stable model can be determined. Further, since a plurality of models can be determined by a series of determination means, it is not necessary to determine which mode switch or the like must be set by the user.

The present invention is not limited to discrimination of video signals from a computer, but is applicable to all video devices that output video signals of various systems.

[0036]

As described above, according to the present invention,
When determining the type of the video device that is the video signal source that is outputting the input video signal, the type of the video device is also determined for the resolution within the same range determined from the horizontal frequency, the vertical frequency, and the polarity of the synchronization signal. Therefore, it is possible to determine even a model that could not be determined conventionally.

According to the present invention, when the resolution of the model determined from the horizontal frequency, the vertical frequency, and the polarity of the synchronization signal is different from the actual resolution obtained from the input video signal, the resolution and the vertical frequency are changed. Since the model is determined based on the resolution, it is possible to prevent the setting of a model that cannot be performed with the resolution, and therefore, it is possible to determine the model (input video signal) more accurately than in the past.

Further, according to the present invention, since a plurality of models can be identified, it is not necessary to operate a changeover switch which had to be operated by a user such as a mode switch in the related art. Troublesome operation of the user can be eliminated.

[Brief description of the drawings]

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

FIG. 2 is a flowchart for explaining the operation of a first determination unit in FIG. 1;

FIG. 3 is a flowchart for explaining the operation of a second determination unit in FIG. 1;

FIG. 4 is a flowchart for explaining the operation of a discrimination / comparison unit in FIG. 1;

FIG. 5 is a schematic diagram showing a first discrimination table used in a first discrimination unit and a discrimination comparison unit in FIG. 1;

FIG. 6 is a schematic diagram showing a second determination table used in a second determination unit in FIG. 1;

[Explanation of symbols]

 1 Standard image data storage unit (ROM) 2 Registered image data storage unit (EEPROM) 3 Control unit 4 Horizontal frequency detection unit 5 Vertical frequency detection unit 6 Synchronous polarity detection unit 7 Input signal detection unit 8 First determination unit 9 Second determination Unit 10 Discrimination comparison unit 11 Central processing unit (CPU) 12 Image data adjustment unit 13 Image display unit

Continuation of the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G09G 5/00-5/40 G09G 1/16 H04N 5/46

Claims (3)

(57) [Claims] An input signal detection unit configured to detect a horizontal frequency and a vertical frequency of an input video signal, and polarities of a horizontal synchronization signal and a vertical synchronization signal, respectively, based on a detection result detected by the input signal detection unit; Model determining means for determining the type of the video device outputting the input video signal; and calculating the number of horizontal lines per vertical cycle based on the detection result detected by the input signal detection unit, and calculating the number of horizontal lines. Resolution determining means for determining the resolution of the video device that is outputting the input video signal, and comparing the model determined by the model determining means with the resolution determined by the resolution determining means. Judge whether the resolution is correct, and if so, determine the model determined by the model determination means as the final model of the video device. Discriminating and comparing means for newly determining the model of the video device outputting the input video signal based on the number of horizontal lines per vertical cycle and the detected vertical frequency, and information on the determined model An image display device, wherein an image is displayed by automatically setting the image. 2. The model discriminating means refers to a first discrimination table in which a horizontal frequency, a vertical frequency, and polarities and resolutions of horizontal and vertical synchronizing signals are respectively associated with a plurality of the models. The resolution determining means determines the resolution by referring to a second determination table in which the resolution and the range of the number of horizontal lines are associated with each other from the calculated number of horizontal lines. When the determined model and the resolution do not match, the comparing unit refers to the first determination table based on the determined resolution and newly determines a model corresponding to the detected vertical frequency. The image display device according to claim 1, wherein: 3. A first storage unit in which standard image data necessary for displaying an image of a plurality of models to be determined, such as resolution and image size correction, of each model is stored in advance, and A second storage unit that stores registered image data such as position correction information of an arbitrary screen registered by a user for at least one of the plurality of models to be determined; 2. The image display device according to claim 1, wherein image data corresponding to the model determined by the comparison means is read from the first and second storage units and set in the image display unit.