JP2010266657A - Display device, program and information storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device and the like capable of appropriately suppressing image-flickering. <P>SOLUTION: A projector 100 is configured to include: a determination unit 130 which determines a dot clock, first horizontal resolution, first vertical resolution and a vertical synchronization frequency on the basis of an input signal including an image signal and a synchronizing signal; a calculation unit 140 which calculates a refresh rate on the basis of the dot clock, the first horizontal resolution, the first vertical resolution, a horizontal value for adjusting the number of pixels in a horizontal direction and a vertical value for adjusting the number of pixels in a vertical direction; and an adjustment unit 150 which adjusts at least one of the horizontal value and the vertical value so that a difference between the refresh rate and the vertical synchronization frequency can become the smallest. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a display device, a program, and an information storage medium.

  For example, Japanese Unexamined Patent Application Publication No. 2007-271665 describes that a scaler has a frame lock function for synchronizing an input vertical synchronization signal and an output vertical synchronization signal. More specifically, in the above publication, when there is a frame lock signal, the previous and current total dots (total number of horizontal pixels) are compared, and if they are different, a new total dot and a default total line are compared. The number (total number of horizontal scanning lines) is set in the digital signal processing IC.

JP 2007-271665 A

  However, the above publication does not describe a method of synchronizing the input vertical synchronization signal and the output vertical synchronization signal. For example, if the input vertical synchronization signal and the output vertical synchronization signal are not synchronized, tearing (flickering of the displayed image) occurs.

  For example, if the vertical sync frequency of the input signal is higher than the refresh rate (vertical sync frequency) of the display device, the display device suppresses tearing by increasing the memory for the display device (for example, using a double buffer). Can be displayed at the refresh rate of the display device. However, when the vertical synchronization frequency of the input signal is less than the refresh rate of the display device, the display device attempts to display at the refresh rate of the display device, and during the processing of one frame, the image read pointer changes the image write pointer. Since the image is overtaken and the content of the image is different in one frame, tearing cannot be suppressed.

  In order to suppress the occurrence of tearing, the display device needs to appropriately adjust the refresh rate of the display device.

  Some aspects according to the present invention provide a display device, a program, and an information storage medium capable of appropriately suppressing image flickering by solving the above-described problems.

  A display device according to one aspect of the present invention determines a dot clock, a first horizontal resolution, a first vertical resolution, and a vertical synchronization frequency based on an input signal including an image signal and a synchronization signal. A determination unit; the dot clock; the first horizontal resolution; the first vertical resolution; a horizontal value for adjusting the number of pixels in the horizontal direction; and a vertical value for adjusting the number of pixels in the vertical direction. A calculation unit that calculates a refresh rate based on the value, and an adjustment unit that adjusts at least one of the horizontal value and the vertical value so that a difference between the refresh rate and the vertical synchronization frequency is minimized. A second horizontal resolution obtained by adding the horizontal value adjusted by the adjustment unit and the first horizontal resolution; the vertical value adjusted by the adjustment unit; and the first vertical resolution. A setting unit for setting a second vertical resolution obtained by adding the door as image information for display, based on the image information, characterized by comprising a display unit for displaying the image.

  According to another aspect of the present invention, there is provided a program for causing a computer to execute a dot clock, a first horizontal resolution, a first vertical resolution, and a vertical synchronization frequency based on an input signal including an image signal and a synchronization signal. And a determination unit for determining, a dot clock, the first horizontal resolution, the first vertical resolution, a horizontal value for adjusting the number of pixels in the horizontal direction, and a number of pixels in the vertical direction And an adjustment unit that adjusts at least one of the horizontal value and the vertical value so that a difference between the refresh rate and the vertical synchronization frequency is minimized, based on a vertical value for calculating the refresh rate. , A second horizontal resolution obtained by adding the horizontal value adjusted by the adjustment unit and the first horizontal resolution, and the vertical adjusted by the adjustment unit When, characterized in that to function as a setting unit for setting a second vertical resolution obtained by adding the first vertical resolution as image information for display.

  An information storage medium according to one aspect of the present invention is an information storage medium that stores a computer-readable program, and stores the program.

  According to the present invention, the display device or the like can appropriately suppress the flickering of the image by setting the image information that minimizes the difference between the refresh rate and the vertical synchronization frequency.

  The adjustment unit may adjust the horizontal value and the vertical value.

  According to this, the display device and the like can adjust the resolution and the like with higher accuracy by adjusting both the horizontal value and the vertical value as compared with the case of adjusting either one.

  The adjustment unit may perform the adjustment when the vertical synchronization frequency is less than the refresh rate.

  According to this, since the display device or the like can perform adjustment only when image flickering is likely to occur, image processing can be performed more efficiently.

It is a functional block diagram of the projector in a 1st Example. It is a flowchart which shows the projection procedure in a 1st Example. It is a flowchart which shows the frame lock control procedure in a 1st Example. It is a flowchart which shows the frame lock control procedure in a 2nd Example.

  Embodiments in which the present invention is applied to a projector will be described below with reference to the drawings. In addition, the Example shown below does not limit the content of the invention described in the claim at all. In addition, all the configurations shown in the following embodiments are not necessarily essential as means for solving the invention described in the claims.

(First embodiment)
The projector of this embodiment has a function of performing frame lock control. With frame lock control, for example, flickering of an image called tearing that occurs when the vertical synchronization frequency (input vertical synchronization frequency) of the input signal is lower than the vertical synchronization frequency (output vertical synchronization frequency, refresh rate) of the display device is suppressed. It is the control for the purpose. Next, functional blocks of a projector having a frame lock control function will be described.

  FIG. 1 is a functional block diagram of a projector 100 according to the first embodiment. The projector 100 includes an input unit 110 that inputs an input signal including an image signal and a synchronization signal, a storage unit 120 that temporarily stores the image signal and the like, a dot clock, and a first horizontal signal based on the input signal. Resolution, first vertical resolution, determination unit 130 for determining the vertical synchronization frequency, dot clock, first horizontal resolution, first vertical resolution, and horizontal for adjusting the number of pixels in the horizontal direction Based on the value and the vertical value for adjusting the number of pixels in the vertical direction, the calculation unit 140 is configured to calculate the refresh rate.

  The first horizontal resolution corresponds to, for example, the minimum number of pixels in the horizontal direction that can be processed as a signal by the display unit 190, and the first vertical resolution is processed by the display unit 190 as a signal, for example. This corresponds to the minimum possible number of pixels in the vertical direction. For example, when the resolution is WXGA (horizontal 1280 pixels, vertical 800 pixels), the first horizontal resolution is about 1820 pixels, and the first vertical resolution is about 815 pixels.

  Further, the projector 100 adjusts the horizontal value and the vertical value so that the difference between the refresh rate and the vertical synchronization frequency is minimized, the horizontal value adjusted by the adjusting unit 150, and the first horizontal value. A setting unit 160 that sets the second horizontal resolution obtained by adding the resolution, the vertical value adjusted by the adjusting unit 150, and the second vertical resolution obtained by adding the first vertical resolution as display image information. And a display unit 190 that displays an image based on the image information.

  The projector 100 may function as each of these units using the following hardware. For example, in the projector 100, the input unit 110 is an image input terminal, a converter, the storage unit 120 is a RAM, a ROM, the determination unit 130, the calculation unit 140, the adjustment unit 150, the setting unit 160 is a CPU, and the display unit 190 is an image. A processing circuit, a lamp, a liquid crystal panel, a liquid crystal driving circuit, a lens, or the like may be used.

  The computer included in the projector 100 may function as the adjustment unit 150 by reading a program stored in the information storage medium 200. As such an information storage medium 200, for example, a CD-ROM, DVD-ROM, ROM, RAM, HDD, or the like can be applied.

  Next, an image projection procedure using these units will be described. FIG. 2 is a flowchart showing a projection procedure in the first embodiment.

  The input unit 110 inputs a signal including an image signal and a synchronization signal from, for example, a PC (Personal Computer) or the like (step S1). The storage unit 120 temporarily stores the image signal.

  The determination unit 130 determines whether the signal type has changed due to, for example, a change in the image supply device (so-called source switching or the like) (step S2). When the signal type changes, the determination unit 130 determines the dot clock DCLK, the first horizontal resolution HPER, the first vertical resolution VLINE, and the vertical synchronization frequency FVin based on the input signal, and the calculation unit 140. Calculates the refresh rate f. Note that f = DCLK / HPER / VLINE.

  The calculation unit 140 determines whether or not the vertical synchronization frequency FVin is less than the refresh rate f (step S3). The projector 100 performs frame lock control when the vertical synchronization frequency FVin is lower than the refresh rate f (step S4), and does not perform frame lock control when the vertical synchronization frequency FVin is equal to or higher than the refresh rate f. Here, since there is sufficient storage capacity for display in the storage unit 120, tearing does not occur. Therefore, the projector 100 does not perform frame lock control when the vertical synchronization frequency FVin is equal to or higher than the refresh rate f. .

  Here, the frame lock control procedure will be described. FIG. 3 is a flowchart showing a frame lock control procedure in the first embodiment.

  The determination unit 130 determines the dot clock DCLK, the first horizontal resolution HPER, the first vertical resolution VLINE, and the vertical synchronization frequency FVin based on the input signal (step S11). This process may be executed when the signal changes as described above.

  The adjustment unit 150 calculates the maximum vertical value Vmax = (DCLK / HPER) / FVin−VLINE, sets 0 as the initial value of the vertical value v, and sets 0 as the initial value of the optimum refresh rate Fvlock. (Step S12).

  Then, the adjustment unit 150 determines whether the vertical value v is less than the maximum value Vmax (step S13). When the vertical value v is less than the maximum value Vmax, the adjustment unit 150 calculates the horizontal value h = DCLK / {FVin * (VLINE + v)} − HPER (step S14).

  Then, the adjustment unit 150 determines whether or not the horizontal value h is 0 or more (step S15). When the horizontal value h is 0 or more, the refresh rate f = {DCLK / (HPER + h)} under the current conditions. / (VLINE + v) is calculated (step S16).

  Then, the adjustment unit 150 determines whether or not the refresh rate f is greater than the optimum refresh rate Fvlock (step S17). When f is larger than Fvlock, the adjustment unit 150 sets f as Fvlock, sets the current horizontal value h as the optimal horizontal value Hlast, and sets the current vertical value v as the optimal vertical value Vlast (step). S18).

  Then, the adjustment unit 150 determines whether Fvlock matches the vertical synchronization frequency FVin (step S19). If Fvlock does not match FVin, or if the horizontal value h is negative in the determination of step S15, the adjustment unit 150 increases the vertical value v by one and continues the processing of steps S13 to S20. To do.

  On the other hand, when Fvlock matches FVin, or when the vertical value v is greater than or equal to the maximum value Vmax, the setting unit 160 adds Hlast to HPER as the final horizontal resolution (second horizontal resolution). Is set as a final vertical resolution (second vertical resolution) by adding Vlast to VLINE (step S21), and these set values are output to the display unit 190 as image information for display.

  The display unit 190 generates an image on the liquid crystal panel based on the image information and the image signal stored in the storage unit 120, and projects the image (step S5). The projector 100 determines whether or not there has been an end instruction from the user (step S6). If there is an end instruction, the series of processing ends, and if there is no end instruction, the series of processing continues.

  As described above, according to the present embodiment, the projector 100 can appropriately suppress the flickering of the image by setting the image information that minimizes the difference between the refresh rate and the vertical synchronization frequency.

  Further, according to the present embodiment, the projector 100 can adjust the resolution and the like with higher accuracy than the case of adjusting either one by adjusting both the horizontal value and the vertical value.

  Further, according to the present embodiment, the projector 100 sets the image information that has been adjusted as described above when the vertical synchronization frequency is less than the refresh rate, and performs the adjustment described above when the vertical synchronization frequency is equal to or higher than the refresh rate. By setting no default image information, adjustment can be performed only when image flickering is likely to occur, so that image processing can be executed more efficiently.

(Second embodiment)
The frame lock control algorithm is not limited to the first embodiment, and various modifications are possible. For example, although the algorithm of the first embodiment is a single loop that increases v by one, a double loop that decreases h by one and increases v by one is adopted as the frame lock control algorithm. May be.

  FIG. 4 is a flowchart showing a frame lock control procedure in the second embodiment. The determination unit 130 determines the dot clock DCLK, the first horizontal resolution HPER, the first vertical resolution VLINE, and the vertical synchronization frequency FVin based on the input signal (step S31).

  The adjustment unit 150 calculates the maximum vertical value Vmax = (DCLK / HPER) / FVin−VLINE, sets 0 as the initial value of the vertical value v, and sets 0 as the initial value of the optimum refresh rate Fvlock. (Step S32).

  Then, the adjustment unit 150 determines whether the vertical value v is less than the maximum value Vmax (step S33). When the vertical value v is less than the maximum value Vmax, the adjustment unit 150 calculates the maximum horizontal value Hmax = DCLK / {FVin * (VLINE + v)} − HPER and sets the horizontal value h = Hmax (step S34). .

  Then, the adjustment unit 150 determines whether or not the horizontal value h is 0 or more (step S35). If the horizontal value h is 0 or more, the refresh rate f = {DCLK / (HPER + h)} under the current conditions. / (VLINE + v) is calculated (step S36).

  Then, the adjustment unit 150 determines whether or not the refresh rate f is greater than the optimum refresh rate Fvlock and the refresh rate f is equal to or lower than the vertical synchronization frequency FVin (step S37). When the determination result in step S37 is true, the adjustment unit 150 sets f as Fvlock, sets the current horizontal value h as the optimal horizontal value Hlast, and sets the current vertical value v as the optimal vertical value Vlast. (Step S38).

  Then, the adjustment unit 150 determines whether Fvlock matches the vertical synchronization frequency FVin (step S39). If Fvlock does not match FVin, or if the determination result in step S37 is false, the adjustment unit 150 decreases the horizontal value h by 1 (step S40), and continues the processing of steps S35 to S39.

  If the horizontal value h is negative in the determination in step S35, the adjustment unit 150 increases the vertical value v by one (step S41), and continues the processing of steps S33 to S40.

  On the other hand, when Fvlock matches FVin, or when the vertical value v is greater than or equal to the maximum value Vmax, the setting unit 160 adds Hlast to HPER as the final horizontal resolution (second horizontal resolution). Is set as a final vertical resolution (second vertical resolution) by adding Vlast to VLINE (step S42), and these set values are output to the display unit 190 as display image information.

  As described above, also according to the present embodiment, the projector 100 has the same function and effect as the first embodiment.

(Other examples)
In addition, application of this invention is not limited to the Example mentioned above, A various deformation | transformation is possible. For example, in the embodiment described above, the adjustment unit 150 adjusts both the horizontal value and the vertical value, but may adjust only one of the horizontal value and the vertical value.

  Further, the display device is not limited to the projector 100, and may be a television, a liquid crystal monitor, or the like, for example.

  Further, the projector 100 is not limited to a liquid crystal projector (transmission type, reflection type such as LCOS), and may be a projector using DMD (Digital Micromirror Device), for example. DMD is a trademark of Texas Instruments Incorporated. Further, the function of the projector 100 may be distributed to a plurality of devices (for example, a PC and a projector).

  100 projector (display device), 110 input unit, 120 storage unit, 130 determination unit, 140 calculation unit, 150 adjustment unit, 160 setting unit, 190 display unit

Claims (5)

A determination unit for determining a dot clock, a first horizontal resolution, a first vertical resolution, and a vertical synchronization frequency based on an input signal including an image signal and a synchronization signal;
Based on the dot clock, the first horizontal resolution, the first vertical resolution, a horizontal value for adjusting the number of pixels in the horizontal direction, and a vertical value for adjusting the number of pixels in the vertical direction. A calculation unit for calculating a refresh rate;
An adjustment unit that adjusts at least one of the horizontal value and the vertical value so that a difference between the refresh rate and the vertical synchronization frequency is minimized;
The second horizontal resolution obtained by adding the horizontal value adjusted by the adjustment unit and the first horizontal resolution, the vertical value adjusted by the adjustment unit, and the first vertical resolution are added. A setting unit for setting the second vertical resolution as display image information;
A display unit for displaying an image based on the image information;
Display device. The display device according to claim 1,
The adjustment unit adjusts the horizontal value and the vertical value.
Display device. The display device according to any one of claims 1 and 2,
The adjustment unit performs the adjustment when the vertical synchronization frequency is less than the refresh rate.
Display device. Computer
A determination unit that determines a dot clock, a first horizontal resolution, a first vertical resolution, and a vertical synchronization frequency based on an input signal including an image signal and a synchronization signal;
Based on the dot clock, the first horizontal resolution, the first vertical resolution, a horizontal value for adjusting the number of pixels in the horizontal direction, and a vertical value for adjusting the number of pixels in the vertical direction. A calculation unit for calculating a refresh rate;
An adjustment unit that adjusts at least one of the horizontal value and the vertical value so that a difference between the refresh rate and the vertical synchronization frequency is minimized;
The second horizontal resolution obtained by adding the horizontal value adjusted by the adjustment unit and the first horizontal resolution, the vertical value adjusted by the adjustment unit, and the first vertical resolution are added. A program for functioning as a setting unit for setting the second vertical resolution as display image information. An information storage medium storing a computer-readable program,
An information storage medium storing the program according to claim 4.

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