KR20100021459A - Dynamic power control for display screens - Google Patents

Abstract

A display system (100) includes a screen (110) configured to display an image with a screen brightness; and a processor (120) configured to divide the screen (110) into zones, to determine a zone brightness of each zone, e.g., via real time content analysis of the image displayed in the zone; and to reduce the screen brightness by a factor when the zone brightness of one of the zones is greater than a threshold. The threshold is associated with a maximum rated current drawn from a power supply (140) driving a zone, and each zone may be driven by a respective power supply (140). The processor (120) may also be configured to measure virtual zone brightness of virtual zones which are moved by a predetermined distance across the screen, and reduce the screen brightness by the factor when the virtual zone brightness of one of the virtual zones is greater than the threshold.

Description

Dynamic power control for display screens {DYNAMIC POWER CONTROL FOR DISPLAY SCREENS}

The present systems and methods relate to dynamic power control (DPC) systems and methods for dynamically changing the brightness of display screens based on dividing the display into zones.

Conventional display screens are used to display video and computer images to individuals and small groups of people. These screens are based on technologies such as cathode ray tubes, LCDs, and plasmas, and they produce high resolution images of brightness sufficient to see the interiors.

In both indoor and outdoor settings, a screen that is 1.5 meters wide and 20 meters wide and larger enough to be used in bright sunlight conditions to display static and moving images to multiple people. An alternative technique is used that can provide for sizes. A technique known to be ideally suited for this task uses light emitting diodes (LEDs) as light generating devices. LED screens have been available for years and hundreds of years and are installed in sports and public places worldwide.

Display screens using LEDs are relatively energy efficient devices, ie their power consumption is proportional to their size and light output. Typically, for a given screen size, power consumption is high when a bright image is displayed and power consumption is small when a dark image is displayed. For LED screens permanently installed in public places, the rating of the power supply (e.g. watts or power ratings) required to provide power to it (i.e. provide adequate voltage and current) is determined by the manufacturer's technical specifications. Can be easily calculated from the data, and the amount of power the screen requires when displaying the brightest image possible (full white light filling the screen) at full rated light output. In this situation, the screen draws most of the power it can draw, i.e. maximum power, and the power supply must be rated enough to handle this maximum power state.

Recently, there are small LED screens (1.5-2 meters wide) in the market, the concept of which is similar to a large plasma or LCD monitor, that is, it can simply be hung on the wall when shopping, advertising A complete monitor in a cabinet, used to display various content such as fields. Typically, this segment of the market is very inexpensive. Thus, it is desirable to have screens that are competitively priced that can be installed by the public, that is, sufficient for the average consumer to install. The simplicity of installation reduces the overall price and can appeal to consumers.

The factors involved in the price are individual or special power lines or feeds to provide the power, voltage, and / or current required for the LED screen, as well as the rating or size of the power required to provide the power required for the LED screen. Includes the costs associated with providing

As mentioned, typically the power consumption of the LED screen is proportional to the brightness of the image displayed. Images vary in brightness content from very dark (non-detailed plain black background) to very bright (non-detailed plain white background).

Since the screen designer does not control the brightness of the content displayed on the LED screen or any other screen, the screen should be designed to cope with the power consumption of the most inferior cases, ie to display a white background. In this case, the screen draws maximum power from the power source. The following factors are considered in designing and installing the display screen:

1. Above any required power, such as when the maximum screen power exceeds 3.5 kW, the screen cannot receive power from a conventional feed, such as from a constant 230V signal phase outlet. In this case, special main feed or power lines must be installed to provide power to the screen, thus increasing the installation cost.

2. The total power rating of the power units inside the screen should be sufficient to deliver maximum power. This requires large and heavy screen power unit (s) where full capacity is not used most of the time. Large screen power supplies also add screen cost and weight, as well as require heat dissipation.

3. Due to the need for increased heat dissipation, the cooling capacity of the ventilation system inside the screen is created during continuous operation at full power (ie during the worst case scenario used to design screen displays). Must cope with increased heat. Thus, more fans are needed to circulate the air, and associated with it increases the price, weight, and noise.

As is apparent, it is desirable to reduce the power requirement of the screen. A simple way to reduce the maximum power drawn by the LED screen is to limit the light output to reduce the lower value, or brightness. While achieving the goal of reducing power, this obviously has the obvious disadvantage of dim and lifelessly displaying all displayed images. Another method of reducing the power dissipated by the screen includes limiting the current provided to the screen as described in Nakamura Patent No. 7,193,592, which is incorporated herein by reference in its entirety.

Nakamura discloses an electro-luminescent (EL) display screen in which pixels are driven by a drive current from a drive circuit. Nakamura's driving circuit limits the current when the total sum of the driving currents increases.

It is desirable to further reduce the power requirements of the screen without substantially affecting the brightness of the content, images or texts displayed on the screen.

One object of the present systems and methods is to overcome the disadvantages of conventional displays. For example, to determine the zone brightness of each zone through real-time content analysis of the image displayed in the zone, and to reduce the screen brightness by a factor when the zone brightness of one of the zones is greater than the threshold, A screen configured to display an image having a screen brightness value; And these and various objects are achieved by a display system having a processor configured to divide the screen into zones.

The threshold is associated with the maximum rate current drawn from the power source driving the zones, and each zone can be driven by a respective power source. The processor also measures the virtual zone brightness of the virtual zones moved by a predetermined number of pixels across the screen, and reduces the screen brightness by a factor when the virtual zone brightness of one of the virtual zones is greater than the threshold. It can be configured to.

Further areas of applicability of the present systems and methods will become apparent from the detailed description provided below. It is to be understood that the detailed description and specific examples depicting illustrative embodiments of the systems and methods are intended for purposes of illustration only and are not intended to limit the scope of the invention.

Various features, aspects, and advantages of the devices, systems, and methods of the present invention will be better understood from the following description, the appended claims, and the drawings.

1-3 illustrate screens divided into eight zones in accordance with example embodiments.

4 is a block diagram illustrating a signal path of an LED screen according to an exemplary embodiment.

5 is a block diagram including a delay element according to another exemplary embodiment.

6-8 illustrate various graphs illustrating the effects of DPC according to another exemplary embodiment.

FIG. 9 illustrates a zoned screen with large, bright graphic objects moving across the screen according to another exemplary embodiment. FIG.

10 illustrates virtual zones according to yet another exemplary embodiment.

The following description of any exemplary embodiments is merely illustrative and is not intended to limit the invention, its applications, or uses. DETAILED DESCRIPTION In the following detailed description of embodiments of the present systems and methods, reference is made to the accompanying drawings, which form a part thereof, and in which are shown by way of specific example embodiments in which the described systems and methods may be practiced. These embodiments are described in sufficient detail to enable those skilled in the art to practice the presently disclosed systems and methods, and other embodiments may be utilized, and structural and logical changes may be made without departing from the spirit and scope of the present system. It should be understood that this can be done.

The following detailed description, therefore, is not to be taken in a limiting sense, and the scope of the present system is defined only by the appended claims. The leading digit (s) of reference numbers in the drawings herein generally correspond to the reference numbers, except that like components appearing in the multiple figures are identified with the same reference numbers. Also, for the sake of clarity, detailed descriptions of well-known devices, circuits, and methods are omitted so as not to obscure the description of the present invention.

The present systems and methods use dynamic power control (DPC) to reduce and limit the maximum power drawn by a screen display device, such as an LED screen, without affecting the quality of images with medium and low brightness content. do. Whenever images containing high brightness content encounter, the DPC automatically and substantially instantaneously reduces the image brightness to a level that maintains total power consumption within a predefined limit.

In addition to not affecting images with medium and low brightness content, the present systems and methods using DPC, for example, instead of a special 3-phase supply, cause the LED screen to display 230V mains. Allows reduction of screen maximum power consumption to a level that allows power from a constant outlet, such as an outlet (or any other suitable voltage level for associated cables suitable for appropriate power, current, and voltage levels). In other words, a special main supply is unnecessary, thereby reducing installation costs. Also, screens with DPC use little electricity, so more economical, smaller / less power supplies are needed inside the screen, thus reducing the cost and weight of the screen. Reduced power consumption reduces heat generation, which in turn reduces the need for cooling. Thus, fewer fans are needed to cool the screen, reducing the cost and weight of the screen and enabling quieter operation.

According to the present systems and methods of using DPC to reduce power consumption without affecting the quality of images with medium and low brightness content, the active area of the screen, such as an LED screen, is divided into zones. Each zone is driven by its own power supply (es) (PSUs). The image signal displayed on the screen is analyzed in real time by dividing the incoming fields into zones that exactly match the screen zones in size. In addition, the pixel luminance value of the brightest zone is determined by determining the zone luminance values or white / light colored image areas of each zone from real-time content analysis, and Such as by selecting a bright zone, such as the most white and / or light colored content or image.

The maximum zone luminance value or the total pixel luminance value of the brightest zone is compared with a predetermined threshold. The threshold is a value that, if obtained by pixels in any one zone, causes the maximum rated current to be drawn from the PSU (s) driving that zone.

If the determined zone luminance value (s) of any one zone exceeds a predetermined threshold, the processor is predetermined or calculated to reduce power consumption and prevent PCUs from being overloaded. Any target factor, which may be a power consumption factor, reduces the output level of the entire screen. When the total pixel level of the highest zone is the same, or falls below the threshold, the processor returns the screen output level to normal.

The target reduction factor of maximum screen power caused by the DPC may be determined by one or more factors. The target may reduce the overall screen power consumption such that the screen can be operated from a typical single phase outlet, for example instead of a three-phase supply. One beneficial by-product is that the quantity of PSUs needed to drive the screen can be reduced in conjunction with cost and weight savings. Alternatively, the target can reduce power consumption to bring it within the range of a certain amount of PSUs or within the capacity of a different specification of the PSU.

The impact of the DPC on the average viewer is generally indistinguishable, and the brightness of the displayed content is reduced when the zone luminance of any one zone exceeds a predetermined DPC threshold. Consider the situation where the image contains small areas of bright detail; This may be below the DPC threshold and the screen output will be at the maximum level. If the image contains increasing areas of bright detail, the screen output level is gradually reduced and vice versa. The tighter the reduction factor, the earlier the screen output level reduction occurs, and the lower it is. A power reduction factor of 0.6 is demonstrated using DPC in accordance with the present systems and methods.

As shown in system 100 of FIG. 1, a display device, such as LED screen 110, may have a brightness of any one zone exceeding a threshold stored in memory 130 coupled to processor 120. In order to display the images and change the screen brightness, the processor 120 is configured to perform a DPC and control the LED screen 110. As is well known, memory 130 may also store application software and other data, including, for example, software instructions for execution by a processor to perform a DPC.

Processor 120 may be configured to divide the active display area of screen 110 into zones, such as eight zones 1 through 8 of the same size and shape. Each zone may be powered by one or more of its own PSUs, with the PSU for zone 1 shown as dashed box 140 in FIG. 1. The size of the zone (measured in pixels) and / or the number of zones may be: power consumption per unit area of the screen at full rate light output; A reduction factor of the maximum screen power expected due to the incorporation of the DPC, such as a reduction factor of 0.6; And a number of factors such as the power rating of the PST (s) of each zone. At full rate output, the power reduction per unit area of the screen can be determined from the manufacturer's specification or by measurement.

During operation, processor 120 analyzes the pixel content of the corresponding respective zone of the incoming image signal in real time, determines the total pixel luminance sum of the brightest zones, and compares it with a predetermined threshold stored in memory 130. Configured to compare. Content analysis is known, as described in US Pat. No. 6,714,594 to Dimitrova and US patent application 2004/0168205 to Nesvadba, each of which is incorporated herein by reference in its entirety. Included in If the determined maximum zone luminance value of the brightest zone or the luminance value of any of the zones exceeds the threshold, the processor 120 is configured to perform a DPC and reduce the overall screen output or brightness level. In order to minimize the frequency of output level reduction, it is desirable to represent the "average" slice of the total image, in the best possible way, for the shape of the zones. Zone shapes have a stated effect on DPC performance.

For example, in FIG. 1, screen 110 is divided into eight zones numbered from 1 to 8; Each zone is for example half the screen 110 height and has different heights (ie, has a partial screen height). When analyzing each zone of FIG. 1, it will be demonstrated that each of the zones 2, 3 has higher total pixel values than any other zone because of the bright areas of those zones 2, 3. High pixel values in zone 2 or 3 may cause the screen output level to be reduced (if higher than the threshold).

Compared to FIG. 1, FIG. 2 shows a screen 210 with eight zones, in which the same image as that of FIG. 1 is displayed except that each zone of the screen 210 is the full (active) screen height. For example, zone analysis performed by processor 120 shows that zones 4 and 5 of FIG. 2 have the highest pixel values. However, the percentage of each of these zones 4, 5 dedicated to bright areas (such as bright clouds in sunlight in the scene shown) is much more than the zones 2, 3 shown in FIG. small. In the case of the screen 210 of FIG. 2, the total pixel luminance sum of each of these zones 4, 5 may be lower than the threshold and therefore does not cause a decrease in the screen output level.

In the examples shown in FIGS. 1 and 2, the eight full-height zones in FIG. 2 are the eight halves of FIG. 1 since the total content or screen brightness is not affected or reduced, i. It can be seen that it gives better results than the height (or partial height) zones. This results in, on average, producing zone brightness less than the threshold, since, in this example, the top of the image contains content that is brighter than the bottom, and the zones are full-height. Of course, it is not always the case that the top of the image is brighter than the bottom, but more often than not. Therefore, the system can have full-height zones that minimize DPC operation and maintain image brightness over the widest range of images. 3 shows one embodiment of a screen 310 having 255x144 pixels, divided into eight full-height zones, each zone being 32x144 pixels.

As mentioned, each zone may have one or more power units PSUs on its own. PSUs are available in a range of output voltages and powers. In conventional screens without DPC, each PSU must be strong enough to drive the area of the screen when the plain white image is displayed (ie, maximum brightness / power). The integration of the DPC allows less powerful (and therefore inexpensive) PSUs to be used, or alternatively, each existing PSU can drive a large area of the screen.

When calculating the required PSU rating per zone, the power reduction achieved by the DPC is considered to yield the PSUs of lower power ratings. Therefore, if the DPC factor is, for example, 0.6, then the maximum power required to drive the zone is:

(P _{ZONE WITH NO DPC} ) x 0.6 Watt

Where P _{ZONE WITH NO DPC} is the power required to display a plain white image on a zone without DPC operation.

An image signal containing content to be displayed on the screen, such as an image, is analyzed to determine the brightness value of each pixel to predict the current drawn by each individual screen pixel when the image is displayed on the screen without a DPC. . If the total current, ie power, of all the pixels in any one zone exceeds the threshold, then the overall screen output level is reduced so as not to exceed the rated power rating of the screen or PSUs.

In order to achieve a fairly accurate prediction of screen pixel performance, it is desirable to make appropriate choices to perform content analysis in the signal path. 4 shows a block diagram 400 illustrating a signal path of an LED screen according to one embodiment, where a composite video signal 450 is received by a video decoder 410 for decoding. The decoded signal passes through the multiplexer (MUX) and because the incoming image is typically slightly higher resolution (eg 720x576 pixels) than the LED screen (eg 256x144 pixels), to match (eg, reduce) the signal resolution to the screen resolution. Multiplied by a scaler (420). Therefore, image resolution is reduced at scaler 420 to a resolution that matches the LED screen.

Image analysis should be done where the entire incoming image is available. This eliminates the later stages of the signal path, where the internal data distribution within the screen physically partitions the image data such that the relevant data is directed only to each part of the screen. After the scaler 420, there is a one-to-one pixel relationship between the image data and the LED screen, so the best analysis is done after the scaler 420. With the integration of field programmable gate array (FPGA) 430 and field storage and memory 435 (associated with the microcontroller), many functions, including image analysis, are performed after the scaler 420 and signal. May be performed before dispensing into the screen 440. The output of the FPGA 430 is provided to a block processor that processes and provides a signal to the line drivers 455 for driving the screen 440. It is desirable to perform content analysis by FPGA 430 after scaler 420.

As shown in FIG. 4, screen 440 includes an internal data distributor 460 to direct relevant data to relevant portions of screen 440. Gamma corrector (465) provides gamma correction. Color correction is also provided by a color corrector 470 for providing a signal to the drivers 475 that drive the LEDs 480 and for displaying content or images on the screen 440.

As an illustrative example, the following assumptions are made in the embodiment shown in FIG. 4: At the output of the scaler 420, the image signal is 8-bit Red-Green-Blue (RGB) luminance data (eg, 3x8 bit streams). One for 'R', one for 'G', one for 'B'); The LED currents for the red, green and blue LEDs are the same.

The following describes a sequence of events during image analysis to calculate a gain factor that will later be applied to the signal path, and to control the screen output level to achieve a target power reduction factor (Factor _{TARGET REDUC} ). :

1. Anti-gamma correction to 8 bit RGB, in processor, apply to scale data as 3x9 bit values. Anti-gamma correction is desirable to emulate what happens to the image data before it is actually displayed on the LED screen. All image signals have a gamma characteristic applied to the source, for example, to increase the dynamic range of dark portions of the image before transmission. This property should be removed from the display device. The data is scaled to 3 × 9 bit values, each with a maximum value of 341. When the R, G, and B values are subsequently summed, this sum has a maximum value of 3x341 = 1023, which is a convenient 10 bit value.

2. Sum the 9 bit RGB luminance values together to produce a luminance value of 0-1023 for each pixel (now 10 bits).

3. Sum the 10 bit pixel luminance values in each zone.

4. At the end of the incoming image fills, compare the zone sums to find the zone with the largest sum of luminance (ZoneSum _MEASURED ). Note that during the initial setup, the system must be calibrated to determine the maximum possible luminance sum per zone. This is accomplished by providing a plain white background as the image source and measuring as above.

5. Adjust the gain factor applied to the LED drivers from the formula below:

Factor _GAIN = ZoneSum _MAXPOSS x Factor _{TARGET REDUC} / ZoneSum _MEASURED

E.g:

If: ZoneSum _MAXPOSS = 800,

ZoneSum _MEASURED = 600,

If Factor _{TARGET REDUC} = 0.6,

Factor _GAIN = 800 x 0.6 / 600 = 0.8.

This should be multiplied by 0.8 (ie, reduced) to provide a target power reduction factor of 0.6 for the LED drivers. It should be noted that it is not desirable to increase the power when displaying dark images, and therefore a formula must be applied to prevent Factor _GAIN from having a value greater than one.

The gain factor should be applied to the appropriate stage in the signal path to provide the desired effect at the appropriate time. The process of measuring pixel values and adjusting the gain factor for the field of the incoming image actually takes one field's duration to complete. Therefore, the calculated gain factor is actually related to the field just passed (ie it is one field that is behind). In order to correctly apply the gain factor, the image signal is delayed by one field between the analysis 510 and the application 520, as shown in the block diagram 500 of FIG. 5, or to process the image signal. There may be a delay by the amount of time required. Therefore, the analyzed signal from the FPGA 430 corresponds to the signal displayed on the screen 440 by the LEDs 480 due to the field delay 530 of the signal from the FPGA 430 to the LEDs 480. do.

An ideal point in the signal path for applying the gain factor is the color correction stage 470 shown in FIG. Here, various changes to the image RGB levels are generally performed, for example to provide accurate white balance and color uniformity. Also at this point, the inherent time delays in data processing (due to the DPC analysis 510 shown in FIG. 5) are likely to be equal to one field duration, and therefore, as much as the delay 530 in FIG. 5. There are advantages that must be considered properly. These results in the gain factor are applied to the correct field of data on which it is based (ie, proper timing), rather than data from the next field, to eliminate temporary PSU overloads.

Practical difficulties may exist in applying the gain factor in color correction stage 470, caused by the fact that this stage is usually physically spread across the entire area of the screen, and therefore, it may be used for all screen areas. At the same time can prove difficult to apply. Thus, although not effective for applying the gain factor, an easy stage is downstream of the data analysis stage in the same FPGA 430 where content analysis is performed. This has the advantage of providing easy access to the data stream, but has the disadvantage that the gain factor is applied to the field of data following its application. This theoretical disadvantage is not really noticeable to the viewer. Transient PSU overloads that can occur in theory are of short (eg one field) duration and are generally easily handled by the PSUs without problems.

The effects of the DPC are described using the following parameters shown in Table 1, where the LED screen with pixel resolution 256x144 pixels is fitted to the DPC and the following measurements are with and without the DPC: It is mentioned in Table 1 which shows a comparison.

 Parimeter  No DPC  With DCP  Power consumption  3.8 kW  2.4 kW  Power reduction factor  -  0.63  Type of main supply  3-ph 400V 16A  Single phase 230V 13A  Quantity of 320W PSUs  24  9  Amount of cooling fans  8  4  Maximum light output-background for 50% of white zone area 2000 cd / m ² 2000 cd / m ²  Maximum Light Output-Background for 76% of White Zone Area 2000 cd / m ² 1810 cd / m ²  Maximum light output-background for 100% of white zone area 2000 cd / m ² 1350 cd / m ²

6-8 show the main supply current of amperage AC on the y axis versus the quantity of rows of pixels illuminated on the screen on the x axis (256 pixels per row), where intermediate The vertical dashed line is the DPC threshold and the right dashed line is the line on which all columns are illuminated, ie the entire screen is driven. In particular, FIG. 6 shows the following states: plain white test pattern; All zones driven; Screen size 256 x 144 pixels (h x v); A.C. Mains current measured with current transducer; And curve 600 of measured main current versus size of illuminated zone area showing the effect of DPC when all zones are driven, under a mains voltage of 235 V A.C.

7 shows the following states, a plain white test pattern; Only one zone driven; Zone size 32 x 144 pixels (h x v); And D.C. Under the PSU current measured with the current transducer, a curve 700 of the measured PSU output current versus the size of the illuminated zone area showing the effect of the DPC when one is driven is the zone.

8 shows the following states, a plain white test pattern; One zone driven; Zone size 32 x 144 pixels (h x v); And under the light output measured with a Minolta CS-100 Chroma Meter at 5 meters, the size of the illuminated zone area versus the small area of the screen, showing the effect of the DPC when one zone is driven. The curve 800 of the light output is shown. Note that the light output per pixel depends on the LED temperature.

Vertical zone analysis is an alternative implementation of DPC zoning. The aforementioned methods involving zones of fixed positions work well with most image materials. However, there are examples in which bright graphical images that track slowly around the screen may allow the DPC to be visible to the viewer of the content or image displayed on the screen.

9 shows a system with a screen 910 divided into eight zones having a large, bright graphical object, such as a content image portion or graphic object 920 that tracks or moves across the screen 910 from position A to position B. FIG. 900 is shown. As in FIG. 2, screen 910 is divided into eight identical full-height zones 1 through 8. However, in situations where a large and bright graphical object 920 is slowly tracked or moved across the screen 910, such as at position A, when the object 920 virtually fills a zone, such as zone 7, perhaps a DPC There may be times, which causes the overall image brightness to decrease, such as when the total pixel brightness of zone 7 is greater than the DPC threshold. For example, when object 920 is in position B, the object's total pixel brightness in any one zone may cause the DPC to cross the two zones, eg, zones 4 and 5, which may prevent the DPC from reducing the overall brightness. There may be other times when 920 is spread.

As the graphical object 920 moves, the effect of the DPC is to slowly oscillate the brightness of the entire screen up and down. This effect can be eliminated by using virtual zone analysis. As before, the virtual zone analysis involves analyzing each 32 x 144 pixels zone (1-8) and identifying the zone with the largest sum of luminance. However, rather than using only eight zones linked directly to their own PSUs, virtual zone analysis finds all possible 32 x 144 (h x v) zones that can exist within the entire screen.

10 illustrates a system 100 configured to use the concept of virtual zone analysis. The first analysis finds the leftmost 32 x 144 pixel region of the screen 1010 (section 1020 as virtual zone 1) and calculates the sum of the total luminance of this virtual zone 1 equal to the fixed zones. . The second analysis moves the virtual zone one pixel to the right (section 1030 as the most zone 2) and calculates the total luminance sum of this virtual zone. The third analysis moves the virtual zone one more pixel to the right or the like. The process repeats until the right side of the screen is reached as shown by section 1040 of screen 1010, which is virtual zone 225. If the screen 910 is 144 pixels x 256 pixels, and each zone with an area of 32 x 144 pixels is gradually moved by one pixel, there are a total of 225 virtual zones. The total pixel luminance sums of the 225 virtual zones are compared with each other to determine the zone with the largest sum, and the largest sum is used in the same manner as before to calculate the gain factor and apply the DPC.

Compared with fixed zone positions, this method of virtual zone analysis has the advantage of eliminating the undesirable vibration effects described in our example, but has the disadvantage of yielding a lower average screen brightness.

As will be appreciated by those skilled in the art in view of the description herein, various modifications may also be provided. The operations of the methods are particularly suitable for being performed by a computer software program. Application data and other data are received by a controller or processor for configuring it to perform operations in accordance with the present systems and methods. Of course, such software, application data as well as memory, such as memory or other memory coupled to a chip, peripheral device or processor in which other data is integrated, may be embedded in a computer readable medium.

Computer-readable media, memory, and / or any other memories can be a combination of long, short, or short-term memories. These memories configure a processor / controller to implement the methods, operations, and functions described herein. The memories may be distributed or local, and the processor on which additional processors may be provided may be distributed or singular. The memories may be implemented as electrical, magnetic or optical memory, or may be implemented as any combination of various types of devices.

Processors and memories can be of any type. The processor may perform the various operations described and execute instructions stored in memory. The processor may be integrated circuit (s) that are application specific or commonly used. In addition, the processor may be a dedicated processor for performing in accordance with the present system, or may be a general purpose processor operative to perform only one of many functions in accordance with the present system. A processor may operate using a program portion, multiple program segments, or may be a hardware device using dedicated or multi-purpose integrated circuits.

Finally, the above description is intended merely to illustrate the present system and should not be considered as limiting the appended claims to any particular embodiment or group of embodiments. Thus, while the system has been described in detail with reference to specific exemplary embodiments, numerous modifications and alternative embodiments may be made without departing from the boundaries and intended spirit and scope of the system as described in the claims below. It should be understood that they may be invented by those skilled in the art. The specification and figures are to be regarded in an illustrative manner, and are not intended to limit the scope of the appended claims.

In interpreting the appended claims, it should be understood that:

a) The word "comprising" does not exclude the presence of elements and operations other than those listed in a given claim;

b) The word "a" or "an" in front of an element does not exclude the presence of a plurality of such elements;

c) any reference numeral in the claims does not limit their scope;

d) Various "means" may be represented by the same or different items or structures or functions implemented in hardware or software.

e) any of the disclosed elements may consist of hardware portions (eg, including discrete and integrated electronic circuits), software portions (eg, computer programming), and any combination thereof;

f) hardware parts may consist of one or both of analog and digital parts;

g) one of the disclosed devices or parts thereof may be combined or separated together with additional parts unless specifically noted;

h) Unspecified series of actions or steps are intended to be required unless specifically indicated.

Claims (19)

In the display system 100, A screen 110 configured to display an image at screen brightness; And A processor configured to divide the screen 110 into zones, determine zone brightness of each zone, and reduce the screen brightness by a factor when the zone brightness of one of the zones is greater than a threshold ( Display system 100. The method of claim 1, Each zone is driven by a respective power source 140. The method of claim 1, And the threshold is associated with a maximum rated current drawn from a power supply (140) driving the zone. The method of claim 1, The factor reduces the highest zone brightness to a value below the threshold. The method of claim 1, The size of the zone is based on at least one of power consumption per selected area of the screen 110 at the full rated light output, the factor, and the power rating of the power sources of the zones. Determined, the display system 100. The method of claim 1, The processor (120) is configured to determine the zone brightness by real time content analysis of the image. The method of claim 1, And a delay circuit (530) for forming a delayed image associated with the image processed by the processor (120) for determining the factor. The method of claim 1, And a scaler (420) configured to match the screen resolution of the screen (110) with the received signal resolution of the image. The method of claim 1, The processor (120) is also configured to determine zone brightness for the output of the scaler (420). The method of claim 1, The processor (120) is also configured to apply the factor at the output of the scaler (420) or during color correction of the image. The method of claim 1, The processor (120) is further configured to measure the virtual zone brightness of the virtual zones moved by a predetermined distance across the screen and to determine the maximum virtual zone brightness. The method of claim 1, The processor 120 also measures the virtual zone brightness of the virtual zones that are moved by a predetermined distance across the screen, and the screen brightness by the factor when the virtual zone brightness of one of the virtual zones is greater than the threshold. Configured to reduce the display system. In the method for controlling the display system 100, Displaying an image on screen 110 at screen brightness; Dividing the screen (110) into zones; Determining zone brightness of each zone; And Reducing the screen brightness by a factor when the zone brightness of one of the zones is greater than a threshold. The method of claim 13, Determining the size of the zone based on at least one of power consumption per selected area of the screen 110 at the full rate light output, the factor, and power ratings of the power sources of the zones. 100 control methods. The method of claim 13, And the determining step determines the zone brightness by real-time content analysis of the image. The method of claim 13, Delaying the image to form a delayed image associated with the processed image used to determine the factor. The method of claim 13, Measuring the virtual zone brightness of the virtual zones that are moved by a predetermined distance across the screen (110) and determining a maximum virtual zone brightness. A computer program, when executed by a computer, which is enabled to carry out the method according to claim 13 or 17. A record carrier for storing a computer program according to claim 18.

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