WO2000058938A1 - Method and device for monitoring the adjustment of the phase pertaining to flat screens - Google Patents

Method and device for monitoring the adjustment of the phase pertaining to flat screens

Info

Publication number
WO2000058938A1
WO2000058938A1 PCT/DE2000/000836 DE0000836W WO0058938A1 WO 2000058938 A1 WO2000058938 A1 WO 2000058938A1 DE 0000836 W DE0000836 W DE 0000836W WO 0058938 A1 WO0058938 A1 WO 0058938A1
Authority
WO
Grant status
Application
Patent type
Prior art keywords
phase
edge
image
pixel
video
Prior art date
Application number
PCT/DE2000/000836
Other languages
German (de)
French (fr)
Inventor
Hase Paul Von
Albertus Soemantri
Original Assignee
Fujitsu Siemens Computers Gmbh
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Family has litigation

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Classifications

    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G5/00Control arrangements or circuits for visual indicators common to cathode-ray tube indicators and other visual indicators
    • G09G5/003Details of a display terminal, the details relating to the control arrangement of the display terminal and to the interfaces thereto
    • G09G5/006Details of the interface to the display terminal
    • G09G5/008Clock recovery
    • GPHYSICS
    • G09EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09GARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00Control of display operating conditions
    • G09G2320/08Arrangements within a display terminal for setting, manually or automatically, display parameters of the display terminal

Abstract

The invention relates to a method and a device for monitoring the adjustment of the phase between the pixel phase of a graphics card and the scanning phase of a flat screen with an analogue interface in a computer system comprising a flat screen and a graphics card. A flag is placed after the phase of the flat screen has been adjusted on the user side. The flag is scanned when the flat screen is switched on or when the video mode on the computer is switched over and/or when the graphics card is exchanged and/or when the computer is interchanged. A display is indicated or adjustment of the phase starts when non-flagging is detected during scanning.

Description

description

A method and device for monitoring the adjustment of the phase in flat panel displays

The invention relates to a method and a device for monitoring the adjustment of the phase between the pixel clock and the sampling clock of a graphics card of a flat screen with an analog interface in a flat panel graphics card computer system.

Flat screens with an analog interface must be adapted to the graphics card of a connected computer. Are sampling phase or wrong, the image appears blurred and interference.

While for standard modes, the values ​​for position, that is, left-right and up-down adjustment, and sampling frequency can be defined as default values, this is not possible for the phase because the phase depends on the graphics card and also of the video line.

In flat panel displays according to the prior art, a microprocessor is usually provided, which takes over the general Steue- tion of the flat screen. This microprocessor is configured so that it can also detect the set on the computer video mode. When the mode has already been set at the factory or by the user, the flat panel display is would with the stored settings for image, sampling frequency and operating phase. Is it in the mode, however, to one which is not yet implemented in the microprocessor of the flat screen, so default position, sampling frequency and phase to be taken. These defaults are not satis- factory in all cases. The setting of the sampling clock and phase have an immediate effect on the image quality. An optimal sampling frequency is given if the scanning of all the pixels followed, for example, a line of a video signal in a stable or characteristic area of ​​these pixels, for example, in the center of each pixel. Then, the data conversion brings optimum results. The image shown has no interference and is stable. In other words, the optimum sampling frequency is equal to the pixel frequency. If an incorrect sampling frequency is set, for example when the sampling clock in comparison with the pixel clock is too fast, the pixels are initially sampled in the allowable range, that is in the middle between two edges, but which are by olgenden pixels more towards scanned up to a flank even the region between two pixels is sampled, which obviously leads to an unsatisfactory image quality. In the area where the pixels are not being scanned in an optimum characteristic range, incorrect samples are derived. The image then shows a strong vertical interference, The greater the difference in frequency between the sampling clock and the pixel clock is, the more areas with vertical interference is visible on the screen.

However, in cases where the sampling is identical to the pixel clock, the image quality may suffer if the phase is not set correctly. The reason is that the scanning takes place in a non-ideal suitable for the overscan region of a pixel, for example, close to the leading or trailing edge of a pixel. This problem can be solved such that the phase, i.e., the sampling time is shifted in total until the scanning is performed in a characteristic or a permissible range of the pixel. When the phase is not set correctly, the image quality is deteriorated on the entire screen by noise signals. Many users do not know the relationship between sampling frequency and phase for image quality. In a blurred image, a defect is suspected and taken customer service to complete. This leads to unnecessary costs. Instructions in the manual or on the packaging of the screen are overlooked by many users. Next is not aware of some users that any resolution used, which is set to a graphics card that requires its own balance. The image quality of the above reasons unsatisfactory, the customer service or the manufacturer's hotline to which the user is notified of the adjustment to be carried out of the phase is contacted at best. In some cases, however, proper monitors to be sent under warranty, although only the stage should be set correctly.

From DE 39 14 249 Al a process for recovery of a generated with an unknown clock input signal is known, in which the input signal is digitized with a reference clock in different phases. (Input signal to compare clock), the difference of the clock frequency of the input signal and the comparison clock is determined from the course of the phase angle and corrects the frequency of the comparison clock accordingly.

In DE 19751719 Al a signal processing method for an analog image signal is described. In this case, the analog picture signal originates from a computing unit, in which the signal in accordance with a graphics standard, such as EGA or VGA, it has been digitally generated, and was then converted to analog form. The method consists in the fact that the analog image signal to an analog / digital conversion is subjected to a first chosen sampling frequency, after which the sampled picture is investigated for picture disturbances back then to determine a corrected sampling frequency. Further measures relate to the determination of the optimum sampling phase and the determination of the exact position of the active picture relative to the horizontal and vertical synchronization pulses.

In view of this the invention has for its object to provide a method and a device for monitoring the adjustment of the phase in flat panel displays, thereby ensuring that the required adjustment of the phase is always carried out when such an adjustment is required.

To achieve this object, the inventive method is characterized in that a flag is set, if the phase of Flachbilschirmes was adjusted user side that the flag when switching on the flat panel display and / or switching of video mode of the computer and / or replacement of the graphics card and / is queried or during the exchange of the computer and that is given a display or initiated an adjustment of the phase, it is determined if ask for the waste, that the flag is not set.

In other words, a flag is inserted in addition to the already stored on each mode settings yet, which is set when the phase is set by the user. So that the user is informed not only by manuals and other accompanying material rather on the need for phase adjustment, but it is, so to speak, each time forced to make the phase setting if necessary.

The flat panel is switched on, or switched to the video mode of the computer, the processor located in the flat panel will query the data stored to the current mode flag. If the flag is set, meaning that the flat has already been set to the system of loading the user, further operation of the system would proceed as usual. If the flag is, however, not yet been set, the flat panel display shows a reaction tion, and there is a corresponding display or an automatic adjustment of phase is initiated.

An advantageous embodiment of the procedure according to the invention Rens is characterized in that the flag is cleared after the change in the video mode of the computer and / or replacement of the graphics card and / or an exchange of the computer. With brand new monitors, the flag should be cleared for all preset modes, since the phase has not yet adjusted to the user's system. Not only in these cases, but also in any change in the system that make a phase adjustment required can be detected by this advantageous embodiment of the method according to the invention. The same applies of course also for modes for which there is no default in flat screen TV.

A further advantageous embodiment of the method according to the invention is characterized in that the flag is set in microprocessor egg ne in the flat panel display or deleted, wherein the display via the OSD is displayed in an advantageous manner. Thus, the existing hardware is used, and it saves costs.

A further advantageous embodiment of the method according to the invention is characterized in that it is checked after the adjustment of the phase and upon detection of a mode change, whether a row, but at least the first line above the image area and / or below the image area and / or a column, but at least the first column of the front-porch-area and / or the back-Porch- area * is "black, and that the flag will only be set if the check is positive. For a review of the phase adjustment made by the user is possible, and the user receives a message if they have undergone phase adjustment is not optimal. A further advantageous embodiment of the method according to the invention is characterized in that an automatic adjustment of the phase is initiated. In contrast to the setting of the phase manually an automatic phase adjustment for many less experienced users is beneficial.

An advantageous embodiment of the method according to the invention is characterized in that the rising edge of a video pulse of a sufficiently bright pixel is determined that the falling edge of the video pulse is determined in a sufficiently bright pixel and that the phase is adjusted so that the sampling in is placed approximately in the center between the rising and the falling edge of a video pulse.

An advantageous embodiment of the method according to the invention is characterized in that the rising edge of a video pulse of a sufficiently bright pixel is ermit- telt, and that the phase is adjusted so that the sampling instant is shifted by approximately half a pixel width in the direction of the pixel center.

An advantageous embodiment of the procedure according to the invention proceedings is characterized in that the falling edge of the video pulse is determined in a sufficiently bright pixel, and that the phase is adjusted so that the sampling instant is shifted approximately by approximately half a pixel width in the direction of the pixel center ,

While the Bildlage- and the sampling frequencies are relatively easily determined by an algorithm and can be adjusted accordingly, the phase position is more difficult to determine. The three exemplary embodiments latter games of the inventive method are simple and satisfactory method of adjusting the phases. An advantageous embodiment of the inventive method, wherein the image area with the image points on the Flachbildschir in rows and columns between a back-porch area and a front porch region are arranged, characterized in that the sufficiently bright image point for determining the rising edge of a pixel m of the first image column next to the back-porch region and a sufficiently bright image point for determining the falling edge of a pixel is walt in the first image column next to the back-porch area. The method is particularly well let exports when as much as possible pronounced edges are evaluated or when nebenemanderliegende areas or points have a very different brightness. Therefore, a point in the first or last image column is particularly suitable because it fully satisfies m combination with the front or back porch area to the required conditions and can be found with relatively little effort.

In an automatic Phasenlagenemstellung special test patterns are needed with alternating white and black pixels in previous flat panels with analog interface usually, the test pattern must be displayed by the graphics card. This has the disadvantage that a software must be installed on the computer and started, and that furthermore this software must be translated for all popular operating systems. In contrast, over the design of the inventions dungsgemaßen process described above, advantageous has the advantage that no such test pattern and no corresponding software required to feeds the automatic phase adjustment.

An advantageous embodiment of the inventive method is characterized in that the brightness of several pixels of the first and the last image column is measured and the pixels with the largest magnitude m of the first or last image column for determining the rising or falling edge of the video pulse are selected. This ensures that image spots may be used with sufficiently pronounced edges for the measurement.

An advantageous embodiment of the method according to the invention is characterized in that first of all the pixels (n × k) with n = 1,2, .... N, and k = constant, for example 10, are measured, and that if a sufficiently bright image point has been found , the pixels of (n + m) xk are measured with m = 1,2, .... N, until a sufficiently bright pixel is found. This is carried out efficiently and in a short time a search for suitable pixels.

An advantageous embodiment of the method according to the invention is characterized in that the phase is shifted for the determination of the amplitude value of the pixel until the measured amplitude values ​​no longer change significantly, and that the amplitude value is then determined is then further processed.

Alternatively, an advantageous embodiment of the method according to the invention is characterized in that the phase used in the determination of the amplitude value is so far preferred to the measured amplitude values ​​are smaller than a predetermined limit, for example less than 50% of the amplitude value, that the phase by half a dot width is delayed, and that the measured amplitude value then is further processed.

The two embodiments of the method, the latter are simple solutions to determine the brightness of the pixel, as a condition for determining the position of the rising and falling edge of the pixel. A further advantageous embodiment of the invention is characterized in that the phase is displaced in the direction of back-porch region to determine the rising edge until the measured amplitude value to a predetermined percentage, for example 50% of the amplitude value previously determined, decreases, and that this value of the phase is stored as the location of the rising edge. Furthermore, an advantageous embodiment of the invention is characterized in that the phase is displaced in the direction of the front-porch-range to determine the trailing edge until the measured amplitude value to a pre surrounded percentage, for example 50% of the amplitude value previously determined, decreases, and that this value of the phase is stored as the location of the falling edge. In this way, the rising and falling edges of two pixels are determined in a simple manner, and the phase can then be set so high that it lies between the rising and the falling edge in about the middle of an image point.

To achieve the above object, the device for monitoring the setting between the pixel clock of a video card and the sampling clock of a flat screen with an analog interface in a flat-Grafikkarte- computer system, characterized by a microprocessor that is configured so that a flag is set when the phase of the flat screen was set user side that the flag at power of the flat screen, or when switching the video mode of the computer and / or replacement of the graphics card and / or replacement of the processor is queried and that an indication given or setting the phase is initiated when it is determined in the query that the flag is not set. The simplicity of the device shows that the invention with the simplest means, and can be implemented very effectively. A further advantageous embodiment of the device according to the invention is characterized by a means for detecting the rising edge of a video pulse of a sufficiently bright image point, for example, in the first image column next to the back-porch area, a device which sufficiently bright, the falling edge of the video pulse in a pixel in the last image column determined in addition to the front-porch area, and with which the phase is adjusted such that the sampling timing is spot laid approximately in the center between the rising and the falling edge of a Videoimpules a setting means.

Further advantageous embodiments of the inventive method or the device of the invention will be apparent from the remaining dependent claims.

Embodiments of the invention will now be described with reference to the accompanying drawings. Show it:

1 shows a block diagram of a connectable to the graphics card of a computer system via an analog interface flat panel display;

Figures 2A and 2B are schematic representations of Videosigna- len;

Figure 3 is a schematic representation of the rising and falling edges of pixels of a video signal; and

Figures 4A and 4B schematically illustrate two ideal video signals and the effect of the location of the sampling pulse in relation to the video signal.

1 shows a control circuit for a flat panel display can be connected via an analog interface, the function with reference to the various input signals and their processing will be explained in more detail. At the input of the control circuit on the one hand, consisting of the three color signals R, G, B video signal and on the other hand, the two synchronization signals H-sync and V-sync for the horizontal and vertical synchronization are. H-sync and V sync are transmitted digitally, wherein the signal voltage V 0 or> 3 V amounts. V-sync signals that the first line of an image is transmitted. Thus, this signal corresponds to the refresh rate and is typically in the range between 60 and 85 Hz. H-sync signals that a new image line is transferred. This signal corresponds to the line frequency and is usually at 60 kHz.

The composed of the color signals R, G, B video signal is an analog signal. The signal voltage is in the range of 0 V and 0.7 V. The pixel clock, that is, the frequency with which the value of this voltage may change, is 80 MHz. As per picture line is transmitted a certain number of pixels, the pixel clock to the number of these points higher than the line frequency (H-sync).

The three color signals R, B, G of the video signal are each fed via a video amplifier VA an analog-to-digital converter ADCR, and ADCG ADCB. The two synchronization signals H-sync and V sync are in separate circuits

HSY VSy processed in such a way that the verschilffenen by transmission and by various EMC measures signal edges are refreshed. This so far processed synchronization signals H-sync and V sync are then fed to a microprocessor uP. This microprocessor uP measures the frequency and determines the m of the graphics card of the computer system set resolution. Each stored on the resolution data are then transmitted to a phase locked loop PLL, as well as parallel thereto realized in a form of an ASIC m logic circuit for

Treatment and processing of digital data transferred. The phase locked loop PLL multiplies the frequency of the synchronous chronisierungssignals H-sync with their about passed from the microprocessor uP value. In this way, the sampling frequency (pixel clock) is obtained. Due to a caused in the phase-locked loop PLL delay time, a phase difference between the pixel clock and sampling is obtained. These two parameters can be influenced via the OSD display on the screen. The sampling frequency recovered in the phase-locked loop is also supplied to the three analog / digital converters ADCR, ADCG, ACDB. These convert the analog data stream m to a digital data stream. The digitized data is then further processed m of the subsequent logic circuit ASIC with the aid of the data contained m a video memory VM. While the data in the simplest case 1 is transmitted to the connectable to the logic circuit ASIC flat panel 1, the video memory VM is often used to provide a time decoupling between the incoming and to reach the flat of the D data to be transmitted. For the interpolation low Auflosungen is likewise possible to employ the data stored in the video memory VM data.

As already mentioned, is in addition to the settings of the position, the sampling frequency and the phase in the microprocessor of the flat screen, a flag overall starts as soon as the phase is set by the user after one in respect to the phase effective change m has been made the flat screen graphics card computer system. The data stored in the Werksemstellung values ​​for the phase can only be default values ​​or suggested values ​​overwritten by the user-side setting.

With brand-new flat-panel displays the flags must be cleared for all preset modes. Even with a change m the graphics card or the computer m setting the stage must be reset, that is, the corresponding flag must be cleared so that the user is drawn to the necessary adjustment in the post-commissioning most of the flat screen. The same applies also for modes for which there is no default in flat screen TV.

If in any case no flag is set and the flat screen is switched on screen, the microprocessor sends a message, for example via the OSD (on screen display) of the flat screen displays and prompts the user to a Phasenemstellung. Otherwise, in the absence of the flag automatic Phasenemstellung can be initiated.

In a preferred Ausfu approximately of the invention, a review of Phasenemstellung made by the user is carried out or checked every mode change if the system has changed. So it is also determined whether the operation performed by the user Phasenemstellung is sufficient. In this review fixed is assumed that the first line or the first line above the image region or the first line or the first line below the image area or the first column or first column next to the front porch area or the first column or the first column * is adjacent to the back porch area "black / SMD. If it is determined during the review that the corresponding lines are not "black *, the image is not properly centered, and it is an adjustment required. Even if the image is centered, but the phase is not properly set, at least one of the verified column or row, is not black as a part of the Bildmformation from the adjacent column / row of the image area is visible. Here, too, an adjustment of the phase is then necessary.

Finally, note that all of the event can be detected in the present invention, in which a Nachemstellung the phase is required, even the case that the flat is operated screen with the same resolution at a different graphics card or another computer.

From the illustrations of Figures 2A and 2B, it must first be seen that the phase of the sampling of the video signal plays an important role in the image quality, and that the phase m many cases must be at different video signals corresponding to different locations. Thus, FIG 2A shows a fast video signal with Uberschw ger, wherein the range of scanning between the rising and the falling edge of the video signal is relatively narrow and m direction is shifted to the falling edge. In contrast, Figure 2B shows sluggish en Video signal without Uberschwmger, WO-in area for the scanning between the rising

Edge and the falling edge is relatively wide and substantially centered. In consideration of the two signals can be seen that there are phase positions, for example at the right edge in the falling edge at the carry video signal in which the measured amplitude values ​​at the carry video signals are no longer useful, while at the same phase position in the rapid video signal still usable amplitude values ​​are measured. On the other hand, it is seen that the ideal phase position m about the center between the rising and the falling edge of Videosi- is gnales and must also be set to this value. Therefore, the adjustment of the phase as a function of the particular system is so important.

As already mentioned, the automatic Phasenemstellung is more problematic than the settings of the other parameters. With reference to the further figures will now be described how such an automatic adjustment can be made.

It is considered when determining the phase angle of the flanks of the video signals. In order to determine an edge, it is advantageous if it is as strong as possible pronounced. This is the case when the signal before the edge is strong as low as possible and behind the edge, or vice versa. The first requirement is met by the ideal Abtastlucke back- and front-porch area, the second by a bright pixel. A bright dot at the beginning of a line is thus very well to the rising, one at the end of a line to determine the falling edge.

That this to edges of two different points that are possibly on different image lines is irrelevant, because the pixel and sampling is known and can be taken into account. The selected image points should m at least one primary color (RGB) have a sufficiently high intensity, so that a sufficiently large in amplitude edge is found.

In principle, each combination is a bright and a dark pixel, which may be located at any point in deosignal Vi to determine the flanks. In most cases, the edges are to be determined by the combination of front / back-porch region and a bright pixel m of the first / last image column. Searching the entire Bildmhaltes after two suitable pairs of points then entfallt.

As already illustrated above, the ideal range for the sampling of the video signal is the one who m the set and actual value of the signal are largely the same. However, the measurement of the amplitude of the video signal in the area of ​​the edge is difficult. The reason for this lies in the jitter of the video signal and the scan pulse. This is large compared to the rise or fall time of the video signal, the edge can be found by averaging several measurements, although, however, an indication of the amplitude of the edge at the measured point can not be made. 4A and 4B illustrate the difficulties in detecting the edges. In the ideal video signals dashed lines are inserted, which are the desired sampling time. The shaded area represents the actually sampled by the jitter at different measurement range. If the measured values ​​telt averaged, resulting in the first case, an average of about 80%. This average value could be wrongly interpreted to mean that you find yourself loading on the rising edge precisely on the spot, has been at the reaches that 80% of the amplitude. However, this is not the case. In the second case, the statement 50%, which already is more appropriate would be.

From these results is obvious that it will hardly be possible because of the JIT ters to determine the location of the edge at which these a certain level has been reached. The slightest mistake you will often then do if you come by averaging the measured values ​​to about 50% of the target. Of course, other values ​​can be searched. Smaller values, for example, have the advantage that the actual amplitude of the image point to be less accurately determined.

In the following, it is assumed that the image position and the sampling frequency are already set correctly. In addition, access to the data of the A / D Wandler should be possible. The rising edge and the falling edge are whereby the following steps are carried out is determined as follows.

rising edge

1. Find a point in the first image column, which has a sufficiently high, the maximum possible R, G or B value.

2. Since the phase may have been preset in the first so that the measurement is faulty, the actual value of the amplitude can be higher. determine the actual value of the amplitude by a measurement at a suitable sampling instant, in that the phase is delayed until the measured amplitude values ​​no longer continue to grow, or by the phase is first brought forward so far until the measured amplitude values ​​are very low, and this value of phase, which marks the beginning of the edge will be delayed by half a pixel width.

3. The phase shift so far m direction back-porch until the average of several measurements sample falls off to about 50% of the m second determined value. This value of the phase caching because here is the rising edge.

Falling edge

4. Find a point in the last image column, which has a sufficiently high, the maximum possible R, G and B value up. Again, a single measurement is sufficient for each to be examined pixel. For the most accurate measurements to be obtained, the stage should be set to the m 2 value found before sampling.

5. The phase shift so far to the front porch until the average sample falls off to about 50% of the m fourth determined value. At this point, there is the falling edge.

Alternatively, the sampling time can also be determined that the rising edge of a video pulse of a sufficiently bright image point is determined and that the phase is adjusted so that the sampling instant is m shifted by approximately half a pixel width in the direction of the pixel center, or that, alternatively, the falling edge of the video pulse is determined in a sufficiently bright pixel, and the phase is set so that the sampling instant is shifted approximately m approximately by half a pixel width in the direction of the pixel center. Then the steps 1 to 5 described above simplify accordingly.

The ideal sampling is theoretically exactly between the two flanks. In practice, it may be advantageous not exactly in the middle between the two sides, but scan slightly delayed to avoid any overshoot the graphics card, as well as to take into account the often slightly exponential Ellem character of the flanks.

The hardware embodiment of the invention comprises a means for detecting the rising edge of a video pulse of a sufficiently bright pixel, a means for detecting the falling edge of the video pulse in a sufficiently bright image point, with which the phase is adjusted to a setting means, that the sampling approximately in the center between the rising and the falling edge of a Videoimpules is placed, and to shift the phase to determine the sample value of the pixel until the measured amplitude values ​​is no longer significantly different means, wherein the sample then determined further is processed.

Furthermore, a device is provided which, when the the

prefers determination of the sample used in phase to such an extent until the measured amplitude values ​​are smaller than a predetermined limit, for example less than 50% of the sample and by a device which then delays the phase by half a pixel width, the then measured sample is further processed.

Finally, a device which as far as the area shifts the phase for determining the rising edge in the direction of back-Porch- until the measured amplitude value to a predetermined percentage, for example 50% of the amplitude value previously determined, drops, this value of the phase as a place of rising edge is temporarily stored, and a device is provided which shifts the phase for determining the falling edge as far toward the front Porch- range until the measured amplitude value to a predetermined percentage, for example 50% of the amplitude value previously determined, drops, which value the phase is stored as the location of the falling edge.

Claims

claims
1. A method for monitoring the adjustment of the phase between the pixel clock of a video card and the sampling clock egg nes flat panel display with an analog interface in a flat panel graphics card computer system, characterized in that a flag is set when the phase of the flat screen set user- was that the flag when switching on the flat panel display and / or switching of video mode of the computer and / or replacement of the graphics card and / or replacement of the processor is queried and that is given a display or initiated an adjustment of the phase when in the is determined query that the flag is not set.
2. The method according to claim 1, characterized in that the flag is cleared after a change in the video mode of the computer and / or replacement of the graphics card and / or an exchange of the computer.
3. The method of claim 1 or 2, characterized in that the flag is set in a microprocessor-¬ sor in the flat panel display or deleted.
4. The method according to claim 1, characterized in that the display via the OSD.
5. The method according to claim 1, characterized in that it is checked after the adjustment of the phase and upon detection of a mode change, whether a row, but at least the first line above the image area and / or below the image area and / or a column, but at least the first column of the front-porch-area and / or the back porch area * is "black, and that the flag will only be set if the check is positive.
6. The method of claim 1, dadurchgekenn - characterized in that an automatic adjustment of the phase is initiated.
7. The method according to claim 6, characterized in that the rising edge of a video pulse of a sufficiently bright pixel is determined that the falling edge of the video pulse is determined in a sufficiently bright pixel, and that the phase is adjusted so that the sampling time m as the halfway between the rising and the falling edge of a video pulse is applied.
8. The method according to claim 6, characterized in that the rising edge of a video pulse of a sufficiently bright image point is determined and that the phase is adjusted so that the sampling instant is m shifted by approximately half a pixel width m direction pixel center.
9. The method of claim 6, dadurchgekenn - characterized in that the falling edge of the video pulse is determined in a sufficiently bright pixel, and that the phase is adjusted so that the sampling et ¬ wa center approximately by half a pixel width m Ricntung pixel shifted becomes.
10. The method according to any one of claims 7 to 9, wherein the image area with the image points on the flat rows and columns between a back porch region and a front-porch area are arranged dadurchge - indicates that a sufficiently bright image point for the determination of the rising edge of a pixel of the first image column next to the back-porch region and a sufficiently bright image point for determining the falling edge is selected, a pixel in the first image column next to the front porch area.
11. The method according to any one of claims 8 to 10, characterized in that the brightness of several pixels of the first and the last image column is measured and the image points with the greatest brightness in the first and last image column are selected for the determination of the rising or falling edge of the video pulse ,
12. The method according to claim 11, characterized in that first of all the pixels (n × k) are treated with n = 1,2, .... N, and k = constant, for example 10, measured, and that if a sufficiently bright image point has been found, the pixels of (n + m) xk are measured with m = 1,2, .... N, until a sufficiently bright Bilαpunkt is found.
13. The method according to any one of claims 8 to 10, characterized in that for the determination of the amplitude value of the pixel, the phase is delayed until the measured amplitude values ​​maybe more alter Si gnifikant and that the amplitude value is then determined is then further processed.
14. A method according to any one of claims 8 to 10, since ¬ by in that the oei the ER averaging of the phase amplitude value used is as far preferable to the measured amplitude values are smaller than a predetermined limit, for example less than 50% of the amplitude value, that the phase is delayed by half a dot width, and that the measured amplitude-then is further processed tudenwert.
15.A method according to any one of claims 8 to 10, since - by in that for determination of the rising edge of the phase is displaced in the direction of back-porch area until the measured amplitude value to a predetermined percentage, for example 50% of the amplitude value previously determined drops, and that this value of the phase is stored as the location of the rising edge.
16. The method according to any one of claims 8 to 10, since - by in that for the determination of the falling edge which phase is displaced in the direction of the front porch-range until the measured amplitude value to a pre surrounded percentage, for example 50% of the previously determined amplitude value, and that decreases DIE ser value of the phase is intermediately stored as the location of the falling edge.
17. The method according to any one of claims 8 to 10, characterized in that the phase relate hung, the sampling instant relative to the center between the rising and the falling edge by a predetermined amount, for example, 10% of pixel width, is delayed.
18. Device for monitoring the setting between the pixel clock of a video card and the sampling clock of a flat screen with an analog interface in a flat panel graphics card computer system, gekennzeichnetdur ch a microprocessor which is gured so config- that a flag is set if the phase of the flat screen was set user side, is that the flag when switching on the flat panel display and / or switching of video mode of the computer and / or replacement of the video adapter and / or the exchange of the computer queried and if an indication that or setting the phase is initiated when it is determined in the query that the flag is not set.
19. Apparatus according to claim 18, characterized in that the microprocessor is configured such that the flag is cleared after a change in the video mode of the computer and / or replacement of the graphics card and / or an exchange of the computer.
20. Apparatus according to claim 18 or 19, dadurchg ek ennzeichnet that the microprocessor, m which the flag is set or cleared, m is arranged the flat panel display.
21. Apparatus according to claim 18, characterized by a display device through which the display via the OSD.
22. A device according to claim 18, characterized by a Uberprufungseinπchtung, it is checked by after the adjustment of the phase and upon detection of a mode change, whether a row, but at least the first line above the image area and / or below the image area and / or a column, but at least the first column of the front-porch-area and / or the back-porch-area "black *, and that the flag is only set if the check is positive.
23. Apparatus according to claim 18, characterized by an e stellemrichtung to initiate an automatic setting of the phases.
24. A device according to claim 23, characterized by a device which determines the rising edge of a video pulse of a sufficiently bright image point m of the first image column next to the back porch area, means that the falling edge of the video pulse m a sufficiently bright pixel of the determined last frame column next to the front-Porch range, and with which the phase is adjusted so that the sampling instant is placed approximately in the center between the rising and the falling edge of a Videoimpules leinrichtung a Emstel-.
25. A device according to claim 23, characterized by a device which determines the rising edge of a video pulse of a sufficiently bright pixel in the first image column next to the back-porch area, and with which the phase is adjusted to a setting means that the sampling is moved in about in about half a pixel width toward the pixel center.
26. Apparatus according to claim 23, characterized by means for pulse, the falling edge of the Videoim- in a sufficiently bright pixel in the last image column next to the front porch area determined and a setting means, with which the phase is adjusted to that the sampling instant is shifted approximately by approximately half a pixel width in the direction of the pixel center.
27. Device according to one of claims 24 to 26, characterized by means to shift the phase to determine the sample value of the pixel until the measured amplitude values ​​do not differ more Si gnifikant, wherein the sample then obtained is further processed.
28. Device according to one of claims 24 to 26, characterized by a device which as far prefers the phase used in the determination of the sample until the measured amplitude values ​​are smaller than a predetermined limit, for example less than 50% of the sample and means which then delays the phase by half a pixel width, the then measured sample is further processed.
29. Device according to one of claims 24 to 26, ge - characterized by a device which as far as Porch section shifts the phase for determining the rising edge in the direction of baking, until the measured amplitude value to a predetermined percentage, for example 50% of the previously determined amplitude value falls, with this value of the phase is temporarily stored as the location of the rising edge.
30. Device according to one of claims 24 to 26, ge - characterized by a device which shifts the phase for determining the falling edge so far in the direction of the front-porch-range until the measured amplitude value to a predetermined percentage, for example 50% of the previously determined amplitude value falls wherein DIE ser value of the phase is intermediately stored as the location of the falling edge.
PCT/DE2000/000836 1999-03-26 2000-03-17 Method and device for monitoring the adjustment of the phase pertaining to flat screens WO2000058938A1 (en)

Priority Applications (2)

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DE1999113915 DE19913915C1 (en) 1999-03-26 1999-03-26 A method and device for monitoring the adjustment of the phase in flat panel displays
DE19913915.6 1999-03-26

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JP2000608360A JP4638606B2 (en) 1999-03-26 2000-03-17 Method and apparatus for monitoring a phase adjustment in flat panel displays
EP20000929228 EP1171867A1 (en) 1999-03-26 2000-03-17 Method and device for monitoring the adjustment of the phase pertaining to flat screens
US09722119 US6693628B1 (en) 1999-03-26 2000-11-27 Method and device for monitoring a setting of a phase in flat screens

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DE19913915C1 (en) 2000-11-23 grant
EP1887556A2 (en) 2008-02-13 application
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