JP3756014B2 - Image display control apparatus, image display control method, and recording medium recording the control program - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an image display control device, a burn-in prevention method used therefor, and a recording medium on which the control program is recorded, and more particularly to a burn-in prevention method for a display device used in a personal computer.
[0002]
[Prior art]
Conventionally, as this type of display device, there are display devices such as a CRT (Cathode-Ray Tube), a liquid crystal display (LCD), and a plasma display panel (PDP).
[0003]
A still image is often displayed on the display screen of this display device, and a screen saver function by software is often used for the purpose of preventing burn-in of the display screen and saving power.
[0004]
Japanese Patent Application Laid-Open No. 8-286647 proposes a display device that facilitates display contents of a regular image in the above screen saver operation and enhances the effect of preventing burn-in.
[0005]
That is, in the burn-in prevention method described in the above publication, when the same image is continuously displayed at the same place on the display screen for a long time, the image currently being operated is less than the display area of the screen. The above effect can be obtained by processing the image and moving the image within the screen.
[0006]
[Problems to be solved by the invention]
In the conventional burn-in prevention method described above, depending on how the software is used, the screen saver function takes a long time or does not work at all.
[0007]
Moreover, in the usage which presupposes displaying the same screen for a long time, such as a guidance display and the information display of an equipment machine, a screen saver function cannot be used and it may become easy to burn-in.
[0008]
In addition, dot matrix display panels such as liquid crystal displays and plasma display panels are often made with the number of pixels that matches the resolution of the personal computer standard. The information display device does not function sufficiently because it is hidden or the operation of the personal computer is hindered.
[0009]
Furthermore, in the burn-in prevention method described in the above publication, the image currently being operated is simply processed into an image smaller than the display area of the screen and the image is moved within the screen, so that the image is displayed within the screen. Blanking parts that are not generated are generated, and nothing is displayed, so that burn-in is likely to occur.
[0010]
SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the above-mentioned problems, and to prevent burn-in without causing lack of information to be displayed and without generating a blanking portion, and a burn-in prevention method used therefor Another object is to provide a recording medium on which the control program is recorded.
[0011]
[Means for Solving the Problems]
  The image display control apparatus according to the present invention reduces or evenly enlarges an input image according to the resolution of the display device.Whether to convert to display imageDisplay image without resolution conversionGetResolution conversion means and the input imageCompare this image data with this input imageDetecting means for detecting that does not change for a certain time;HaveWhen the input means detects that the input image does not change for a certain timeThe predetermined area of the display image is enlarged and other areas are reduced so that the information on the display image is not lost and a blanking portion where the image signal of the input image is not displayed is generated. Change the enlargement area and reduction area when it is detected that it does not change for a certain period of time.ControlRukoAnd features.
[0012]
  According to the present inventionImage display control methodReduced or evenly enlarged the input image according to the resolution of the display device.Whether to convert to display imageDisplay image without resolution conversionAndThe input imageCompare this image data with this input imageDoes not change for a certain timeDetectedSometimesThe predetermined area of the display image is enlarged and other areas are reduced so that the information on the display image is not lost and a blanking portion where the image signal of the input image is not displayed is generated. Control to change the enlargement area and reduction area when it is detected that it does not change for a certain period of timeIt is characterized by that.
[0013]
  According to the present inventionImage displayA recording medium on which a control program is recorded is provided for causing an image display control device that controls display of an input image on a display device to prevent burn-in of a display screen of the display device.Image displayA recording medium having a control program recorded thereon,Image displayThe control program causes the image display control device to uniformly reduce or evenly enlarge the input image in accordance with the resolution of the display device.Whether to convert to display imageDisplay image without resolution conversionAndThe input imageCompare the image data of thisInput image does not change for a certain timeDetectedSometimesThe predetermined area of the display image is enlarged and other areas are reduced so that the information on the display image is not lost and a blanking portion where the image signal of the input image is not displayed is generated. Control to change the enlargement area and the reduction area when it is detected that it does not change for a certain period of time.It is characterized by that.
[0014]
  It is preferable that the input image is changed to the original resolution and displayed on the entire screen when the number of times that the input image has not been changed for a certain period of time is detected.
[0015]
Thus, CRT (Cathode-Ray Tube), liquid crystal display (LCD), and plasma display panel (PDP: Plasma Display Panel) can be obtained without missing information to be displayed and without generating a blanking portion. ) And the like on the display device can be reduced.
[0016]
  That is, in the present invention, an operation for combining the operation of changing the size and position of the display screen is performed.ByWithout missing any information to be displayed, while displaying the same information on the screen and paying attention to a certain display position on the display device, the display content changes with time, so burn-in can be reduced.
[0017]
DETAILED DESCRIPTION OF THE INVENTION
Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of an image display control apparatus according to a first embodiment of the present invention. In FIG. 1, an image display control device 1 includes an A / D (analog / digital) conversion unit 11, a resolution conversion unit 12, a blanking designation unit 13, a position change timing control unit 14, and a still image detection unit 15. And a time measurement unit 16 and a size / position control unit 17.
[0018]
The image display control apparatus 1 controls image display on a display device [for example, a liquid crystal display (LCD), a plasma display panel (PDP), etc.] 2. Each unit in the image display control device 1 realizes each process by executing a program stored in a control memory (not shown). As the control memory, a ROM (Read Only Memory) or an IC (Integrated Circuit) memory is used. It can be used.
[0019]
When an image signal having a resolution of 640 * 480 dots is input to the display device 2, the image display control device 1 converts the image signal input by the A / D converter 11 into digital data.
[0020]
The resolution converter 12 converts the digital data converted by the A / D converter 11 into image data having a resolution of 600 * 460 dots according to the image size designation data Ds from the size / position controller 17.
[0021]
At this time, since the converted image data is smaller in size by 40 dots in the horizontal direction and 20 dots in the vertical direction than the original image, a blanking portion where no image is displayed on the display device 2 occurs. If no image is displayed in the blanking portion, it is easy for burn-in to occur in that portion, so it is necessary to avoid the burn-in.
[0022]
Therefore, when the image data from the resolution conversion unit 12 is input, the blanking designation unit 13 adds display data of the blanking portion to the image data so that some display can be performed on the blanking portion. It outputs to the timing control part 14 for a change.
[0023]
The position change timing control unit 14 changes the timing relationship between the image data from the blanking designating unit 13 and the horizontal / vertical synchronization signal Si in accordance with the position data Dp from the size / position control unit 17 to change the image data Da and the synchronization signal. S is output to the display device 2. In order to change the timing of the image data and the horizontal / vertical synchronization signal Si, the position change timing control unit 14 delays the input image data Dp and the horizontal / vertical synchronization signal Si by a desired time.
[0024]
The display device 2 determines the display position of the image data Da according to the timing of the image data Da and the synchronization signal S. The size / position control unit 17 controls the resolution conversion unit 12 and the position change timing control unit 14 in accordance with the burn-in prevention operation trigger signal Trg and the burn-in prevention operation reset signal Rst from the time measurement unit 16 to perform the operation of the burn-in prevention function. Control.
[0025]
FIG. 2 is a block diagram showing a configuration of the still image detection unit 15 of FIG. In FIG. 2, the still image detection unit 15 includes a frame memory 15a, an inter-frame pixel data comparison unit 15b, a coincidence number counting unit 15c, a count value comparison unit 15d, and a still image detection threshold storage unit 15e. It is composed of
[0026]
The still image detection unit 15 detects whether the input image is a still image. That is, the still image detection unit 15 first stores image data for one frame in the frame memory 15a. When the next frame image is input, the data stored in the frame memory 15a is read, and the inter-frame pixel data comparison unit 15b compares the image data at the same position one frame before with the current one.
[0027]
The inter-frame pixel data comparison unit 15b outputs a signal representing “1” to the coincidence number counting unit 15c if the image data are coincident with each other and “0” if they are not coincident. The coincidence number counting unit 15c counts the number of “1” (the number of coincidences) input from the inter-frame pixel data comparison unit 15b, and obtains the coincidence pixel number Cnt between two frames.
[0028]
Next, the count value comparison unit 15d compares the still image detection threshold value S from the still image detection threshold value storage unit 15e with the coincidence pixel number Cnt from the coincidence number count unit 15c, and Cnt ≧ S. Sometimes it is determined that the input image is a still image, and the still image determination signal Dj is output as “1”.
[0029]
FIG. 3 is a block diagram showing the configuration of the time measuring unit 16 of FIG. In FIG. 3, the time measuring unit 16 includes a determination signal counting unit 16a, a count value comparison unit 16b, and a trigger generation threshold storage unit 16c.
[0030]
The time measuring unit 16 uses the still image determination signal Dj to measure the time t during which the still image continues, and generates a burn-in prevention operation trigger signal Trg and a burn-in prevention operation reset signal Rst for changing the size / position. .
[0031]
The time measuring unit 16 inputs the vertical synchronization signal VS and the still image determination signal Dj to the determination signal count unit 16a. The determination signal counting unit 16a advances the count value by 1 when the still image determination signal Dj is “1” when the vertical synchronization signal VS is input, and the count value when the still image determination signal Dj is “0”. To reset. In this case, the count value t is the time during which the still image continues.
[0032]
The count value comparison unit 16b compares the count value t from the determination signal count unit 16a with the trigger generation threshold value tx from the trigger generation threshold storage unit 16c, and when t ≧ tx, the burn-in prevention operation trigger signal. Trg is generated. When the burn-in prevention operation trigger signal Trg is input to the size / position control unit 17, the size control data Ds and the position control data Dp are output to perform the burn-in prevention operation.
[0033]
When the determination signal count unit 16a is reset and the count value t = 0, the count value comparison unit 16b determines that the input image is a moving image and generates a burn-in prevention operation reset signal Rst. When the burn-in prevention operation reset signal Rst is input to the size / position control unit 17, the size control data Ds and the position control data Dp are output to cancel the burn-in prevention operation, and the size conversion and the display position are in the standard state. Return to.
[0034]
FIG. 4 is a diagram showing an example of the burn-in prevention operation according to the first embodiment of the present invention, and FIG. 5 is a flowchart showing the burn-in prevention operation according to the first embodiment of the present invention. The burn-in preventing operation according to the first embodiment of the present invention will be described with reference to FIGS. Hereinafter, an application example in a display device for a personal computer using a plasma display panel having a resolution of 640 * 480 dots as the display device 2 will be described.
[0035]
When an image signal having a resolution of 640 * 480 dots is input to the display device 2, the image display control apparatus 1 normally displays the image signal in a state in which the resolution is not converted as shown in FIG. (Step S1 in FIG. 5).
[0036]
If the image signal is displayed on the display device 2 for a long time in a state where the resolution is not converted, the displayed pattern remains on the display device 2. Therefore, when the image display control apparatus 1 detects that the input image does not change for a certain time by the still image detection unit 15 and the time measurement unit 16 (step S2 in FIG. 5), as shown in FIG. Then, the resolution of the image signal is changed to reduce it to 600 * 460 dots, and the blanking portion 13 performs gray display (steps S3 and S4 in FIG. 5).
[0037]
Further, when the image display control device 1 detects that the input image does not change for a certain time by the still image detection unit 15 and the time measurement unit 16 (step S5 in FIG. 5), as shown in FIG. The display data of the reduced image and the blanking portion is moved so that the reduced image is moved to the right by the control unit 14 (step S6 in FIG. 5).
[0038]
Furthermore, if the input image does not change for a certain period of time (step S7 in FIG. 5), the image display control apparatus 1 moves the image every predetermined time and sequentially displays it at the positions of FIGS. 4-B to D (step S6 in FIG. 5). . In this way, the image display control apparatus 1 moves the display data of the reduced image and the blanking portion up and down, left and right, and moves the 600 * 460 image to an arbitrary position in the 640 * 480 screen.
[0039]
Further, the image display control device 1 is also combined with an operation (step S9 in FIG. 5) for returning the image signal to full screen every time the reduced image and the display data of the blanking portion are moved a predetermined number of times (step S8 in FIG. 5). The same display state is not continued (steps S3 to S10 in FIG. 5), and the burn-in on the display screen of the display device 2 is reduced.
[0040]
In addition, by changing the conversion size (reduction, enlargement, etc.) of the image, the distance of moving the display data in the blanking portion, the time, etc., it is possible to make a setting that enhances the above effect according to the display image. .
[0041]
FIG. 6 is a diagram showing an example of the burn-in prevention operation according to the second embodiment of the present invention, and FIG. 7 is a flowchart showing the burn-in prevention operation according to the second embodiment of the present invention. The image display control apparatus according to the second embodiment of the present invention has the same configuration as the image display control apparatus 1 according to the first embodiment of the present invention shown in FIGS. Is omitted.
[0042]
The burn-in prevention operation according to the second embodiment of the present invention will be described with reference to FIGS. Hereinafter, an application example in a display device for a personal computer using a plasma display panel having a resolution of 640 * 480 dots as the display device 2 will be described.
[0043]
When an image signal having an 800 * 600 dot resolution is input to the display device 2, the image display control apparatus 1 normally displays 640 * 480 dots with uniform reduction as shown in FIG. 6A. (Step S11 in FIG. 7), if the display is continued for a long time, the display screen of the display device 2 is burned.
[0044]
Therefore, when the image display control device 1 detects that the input image does not change for a certain period of time (step S12 in FIG. 7), as shown in FIG. 6B, the upper left reduction ratio is increased and the lower right reduction ratio is increased. The size is reduced to 640 * 480 dots (step S13 in FIG. 7) and displayed on the display device 2. At that time, the blanking portion display data is not added by the blanking designation unit 13.
[0045]
Furthermore, if the input image does not change for a certain period of time (step S14 in FIG. 7), the image display control device 1 increases the lower right reduction ratio and decreases the upper left reduction ratio as shown in FIG. Are displayed (step S15 in FIG. 7).
[0046]
In this way, the image display control apparatus 1 moves the center of gravity of the reduction of the image signal so that the same display state does not continue (steps S15 to S17 in FIG. 7), and reduces burn-in on the display screen of the display device 2.
[0047]
The image display control device 1 also performs an operation (step S18 in FIG. 7) that causes the image signal to have an equal reduction ratio every time the center of gravity of the image signal is reduced a predetermined number of times (step S17 in FIG. 7). The combination and the same display state are not continued (steps S13 to S19 in FIG. 7), and the burn-in of the display screen of the display device 2 can be reduced without generating a blanking portion.
[0048]
FIG. 8 is a flowchart showing the burn-in preventing operation according to the third embodiment of the present invention. The image display control apparatus according to the third embodiment of the present invention has the same configuration as the image display control apparatus 1 according to the first embodiment of the present invention shown in FIGS. Is omitted.
[0049]
The burn-in preventing operation according to the third embodiment of the present invention will be described with reference to FIGS. Hereinafter, an application example in a display device for a personal computer using a plasma display panel having a resolution of 640 * 480 dots as the display device 2 will be described.
[0050]
When an image signal with a resolution of 640 * 480 dots is input to the display device 2, the image display control apparatus 1 normally displays 640 * 480 dots as it is (step S21 in FIG. 8). 2 is burned in on the display screen.
[0051]
Therefore, when the image display control device 1 detects that the input image does not change for a certain time (step S22 in FIG. 8), the image size is converted to 640 * by reducing a part of the image and enlarging the other part. It is maintained at 480 dots (step S23 in FIG. 8) and displayed on the display device 2. At that time, the blanking portion display data is not added by the blanking designation unit 13.
[0052]
Furthermore, when the input image does not change for a certain period of time (step S24 in FIG. 8), the image display control device 1 changes the resolution so as to change the area to be reduced and enlarged (step S25 in FIG. 8).
[0053]
In this way, the image display control apparatus 1 reduces the part of the image signal and enlarges the other part so that the same display state does not continue (steps S25 to S27 in FIG. 8). Reduce burn-in on the display screen.
[0054]
The image display control apparatus 1 also performs an operation of returning the image signal to the original resolution (step S28 in FIG. 8) every time the image signal is reduced and enlarged in a predetermined number of times (step S27 in FIG. 8). The combination and the same display state are not continued (steps S23 to S29 in FIG. 8), and the burn-in of the display screen of the display device 2 can be reduced without generating a blanking portion.
[0055]
FIG. 9 is a flowchart showing a burn-in prevention operation according to the fourth embodiment of the present invention. The image display control apparatus according to the fourth embodiment of the present invention has the same configuration as that of the image display control apparatus 1 according to the first embodiment of the present invention shown in FIGS. Is omitted.
[0056]
The burn-in prevention operation according to the fourth embodiment of the present invention will be described with reference to FIGS. Hereinafter, an application example in a display device for a personal computer using a 800 * 600 dot resolution plasma display panel as the display device 2 will be described.
[0057]
When an image signal having a resolution of 640 * 480 dots is input to the display device 2, the image display control apparatus 1 normally displays 800 * 600 dots in an evenly enlarged manner (step S31 in FIG. 9). Then, burn-in occurs on the display screen of the display device 2.
[0058]
Therefore, when the image display control device 1 detects that the input image does not change for a certain period of time (step S32 in FIG. 9), the enlargement factor in the upper left direction is increased and the enlargement factor in the lower right direction is reduced, that is, the enlargement factor is not set. It is uniformly enlarged to 800 * 600 dots (step S33 in FIG. 9) and displayed on the display device 2. At that time, the blanking portion display data is not added by the blanking designation unit 13.
[0059]
Further, when the input image does not change for a certain period of time (step S34 in FIG. 9), the image display control device 1 displays the image with the lower right enlargement factor increased and the upper left enlargement factor decreased (step S35 in FIG. 9). .
[0060]
In this way, the image display control device 1 moves the center of gravity of the expansion of the image signal so that the same display state does not continue (steps S35 to S37 in FIG. 9), and reduces burn-in on the display screen of the display device 2.
[0061]
The image display control apparatus 1 also performs an operation (step S38 in FIG. 9) that causes the image signal to have an equal enlargement ratio every time the center of gravity of the image signal is expanded a predetermined number of times (step S37 in FIG. 9). The combination and the same display state do not continue (steps S33 to S39 in FIG. 9), and the burn-in of the display screen of the display device 2 can be reduced without missing information or without generating a blanking portion.
[0062]
FIG. 10 is a block diagram showing the configuration of an image display control apparatus according to the fifth embodiment of the present invention. In FIG. 10, the image display control apparatus 3 according to the fifth embodiment of the present invention adds a D / A (digital / analog) conversion unit 31 and connects to a CRT (Cathode-Ray Tube) 4 instead of the display device 2. Except for this, the configuration is the same as that of the image display control apparatus 1 according to the first embodiment of the present invention shown in FIG. 1, and the same components are denoted by the same reference numerals. The operation of the same component is the same as that of the first embodiment of the present invention.
[0063]
The image display control device 3 according to the fifth embodiment of the present invention is for applying this function to an image output device or a CRT display device having no display device. In this case, since it is necessary to output an analog image signal, the digital video data Da output from the position change timing control unit 14 is D / A converted by the D / A conversion unit 31 and then output to the external output terminal or CRT 4. Sending out.
[0064]
In the first to fifth embodiments described above, still image detection, image size conversion, and generation of a display image signal whose position has been moved are performed using hardware. It is also possible to realize the generation of the display image signal converted and moved by software.
[0065]
In this way, by changing the display position while changing the resolution of the image and adding the blanking portion display data to the image signal whose resolution has been changed when the blanking portion is generated by changing the resolution, the display device 2 or The burn-in on the display screen of the CRT 4 can be reduced, and a display with no missing information can be obtained at the same time.
[0066]
In a dot matrix display device, an image to be originally displayed is hidden by simply shifting the display position. However, by shifting the position in a state where the image size is reduced, display without missing information is performed. The burn-in on the display screen of the device 2 or the CRT 4 can be reduced.
[0067]
Further, the burn-in phenomenon in the display device 2 or the CRT 4 is likely to occur when an image having a large luminance difference between adjacent pixels, such as an image in which black and white are adjacent to each other, is displayed. On the other hand, when converting the resolution, if a high-frequency component is removed from the original image to make it look soft, the luminance difference between adjacent pixels is reduced. Therefore, the burn-in on the display screen of the display device 2 or the CRT 4 can be reduced only by displaying a soft image by resolution conversion.
[0068]
Furthermore, in recent years, in order to display images with various resolutions on a dot matrix display device such as the display device 2, it is necessary to mount a resolution conversion function on the display device 2. Therefore, in a device that already has a resolution conversion function, it is possible to relatively easily apply the burn-in prevention operation at a low cost.
[0069]
Furthermore, when a similar effect is to be obtained in a display device using CRT4, a method of changing the image size and position by electron beam deflection operation instead of resolution conversion can be considered, but subtle adjustment of the deflection operation is possible. Necessary and difficult to implement. On the other hand, the method according to the present invention is based on resolution conversion and can be performed relatively easily by digital processing.
[0070]
【The invention's effect】
  As explained above, according to the present invention,, tableThere is an effect that burn-in can be reduced without missing information to be shown and without generating a blanking portion.
[Brief description of the drawings]
FIG. 1 is a block diagram showing a configuration of an image display control apparatus according to a first embodiment of the present invention.
2 is a block diagram illustrating a configuration of a still image detection unit in FIG. 1;
FIG. 3 is a block diagram illustrating a configuration of a time measurement unit in FIG. 1;
FIG. 4 is a diagram showing an example of a burn-in prevention operation according to the first embodiment of the present invention.
FIG. 5 is a flowchart showing a burn-in prevention operation according to the first embodiment of the present invention.
FIG. 6 is a diagram showing an example of a burn-in prevention operation according to the second embodiment of the present invention.
FIG. 7 is a flowchart showing a burn-in prevention operation according to the second embodiment of the present invention.
FIG. 8 is a flowchart showing a burn-in prevention operation according to a third embodiment of the present invention.
FIG. 9 is a flowchart showing a burn-in prevention operation according to a fourth embodiment of the present invention.
FIG. 10 is a block diagram showing a configuration of an image display control apparatus according to a fifth embodiment of the present invention.
[Explanation of symbols]
1,3 Image display control device
2 display devices
4 CRT
11 A / D converter
12 Resolution converter
13 Blanking specification part
14 Position change timing controller
15 Still image detector
15a frame memory
15b Each pixel data comparison unit between frames
15c Match count section
15d Count value comparison unit
15e Threshold storage unit for still image detection
16 hour measuring part
16a judgment signal count section
16b Count value comparison unit
16c Trigger generation threshold storage unit
17 Size / position control unit
31 D / A converter

Claims (5)

The combined input image on the display device resolution, convert the equally reduced or uniformly enlarged display image, or a resolution conversion unit for obtaining a display image without resolution conversion, this by comparing the image data of the input image Detecting means for detecting that the input image does not change for a certain period of time , and when the detection means detects that the input image does not change for a certain period of time, the information on the display image is not lost, and the input image The predetermined area of the display image is enlarged and other areas are reduced so that a blanking portion where no image signal is displayed is generated, and when the input image is detected not to change for a certain period of time, the enlarged area is reduced. image display control device comprising a benzalkonium controls to change the area. Claim the number of times of the input image is detected that no change fixed time before Symbol detection means is characterized by being configured so as to fully display by changing the input image based on the resolution when a predetermined number of times The image display control device according to 1. The combined input image on the display device resolution, equally reduced or uniformly be converted to enlarged display image, or to obtain a display image without resolution conversion, the input image by comparing the image data of the input image is constant The predetermined area of the display image is enlarged to other areas so that the information of the display image is not lost when it is detected that the time does not change and a blanking portion where the image signal of the input image is not displayed is generated. reducing the further image display control method, wherein the input image is controlled so as to change the enlargement area and a reduction area when it is detected that does not change a predetermined time. When the number of times that the input image is not changed for a certain time is detected it has reached a predetermined number of times, an image according to claim 3, comprising the step of entire screen display by changing the input image based on the resolution Display control method . A recording medium recording an image display control program for preventing an image display control device for controlling display of an input image on a display device to prevent burn-in of a display screen of the display device, wherein the image display control program includes: the image display control device, the combined input image to the resolution of the display device, equally be converted to reduction or uniformly enlarged display image, or to obtain a display image without resolution conversion, by comparing the image data of the input image without that lack information at the display image it was detected that lever of the input image is not changed for a certain time, and as blanking portion image signal is not displayed in the input image is not generated, a predetermined area of the display image To zoom in and reduce other areas, and when it is detected that the input image does not change for a certain period of time, the enlargement area and the reduction area are changed. Recording medium recording an image display control program according to claim Rukoto is controlled such.

Images