This application claims priority to Taiwan Application Serial Number 108119566, filed Jun. 5, 2019, which is herein incorporated by reference.
The disclosure relates to a backlight signal processing method and a display device, particularly to a backlight signal processing method and a display device for adjusting backlight brightness.
With development of technology, the demand for display devices becomes more and more extensive. Conventionally, liquid crystal displays (LCDs) may be used with dynamic backlight technology to increase contrast. However, limited by size, under the same number of backlight areas, backlight diffusion will be more serious than in the past, thus affecting the quality of the displayed image.
Therefore, how to improve the control method of the backlight signal to effectively improve the contrast of the image is the current design consideration and challenge.
One aspect of the present disclosure is a backlight signal processing method suitable for a display device including a backlight module and a LCD panel, wherein the number of a plurality of emitting areas of the backlight module is smaller than the number of a plurality of pixels of the LCD panel. The backlight signal processing method including: generating a plurality of first gray level data signals according to a plurality of color data signals; grouping the first gray level data signals to calculate a plurality of second gray level data signals, wherein the number of the second gray level data signals is smaller than the number of the first gray level data signals; multiplying a coefficient matrix to obtain a plurality of gray level matrices; performing an overlapping operation on the gray level matrices to obtain a backlight matrix; and controlling the plurality of emitting areas to display according to the backlight matrix respectively.
One aspect of the present disclosure is an another backlight signal processing method, including: when an input image signal is input to a display device, converting, by the display device, the input image signal into an output image signal, where the resolution of the output image signal is less than the resolution of the output image signal; the input image signal comprising a first total number of pixels and a first high-brightness pattern, the output image signal comprising a second high-brightness pattern and a second total number of pixels which is lower than the first total number of pixels, a width of the pixel of the second high-brightness pattern is larger than a width of the pixel of the first high-brightness pattern.
Another aspect of the present disclosure is a display device. The display device includes a backlight module, a LCD panel, and a control circuit. The backlight module includes a plurality of emitting areas. The LCD panel includes a plurality of pixels. The number of plurality of pixels is larger than the number of the plurality of emitting areas. The control circuit is coupled to the backlight module and the LCD panel. The control circuit is configured to perform the following operations: generating a plurality of first gray level data signals according to a plurality of color data signals; grouping the plurality of first gray level data signals to calculate a plurality of second gray level data signals, wherein the number of the plurality of second gray level data signals is smaller than the number of the plurality of first gray level data signals; multiplying the plurality of second gray level data signals by a coefficient matrix to obtain a plurality of gray level matrices; performing an overlapping operation on the gray level matrices to obtain a backlight matrix; controlling the plurality of emitting areas to display according to the backlight matrix respectively; and controlling the plurality of pixels to display according to the plurality of color data signals respectively.
The following embodiments are disclosed with accompanying diagrams for detailed description. For illustration clarity, many details of practice are explained in the following descriptions. However, it should be understood that these details of practice do not intend to limit the present disclosure. That is, these details of practice are not necessary in parts of embodiments of the present disclosure. Furthermore, for simplifying the diagrams, some of the conventional structures and elements are shown with schematic illustrations.
The terms used in this specification and claims, unless otherwise stated, generally have their ordinary meanings in the art, within the context of the disclosure, and in the specific context where each term is used. Certain terms that are used to describe the disclosure are discussed below, or elsewhere in the specification, to provide additional guidance to the practitioner skilled in the art regarding the description of the disclosure.
It will be understood that, although the terms “first,” “second,” etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used to distinguish one element from another. For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element, without departing from the scope of the embodiments.
In this document, the term “coupled” may also be termed “electrically coupled,” and the term “connected” may be termed “electrically connected.” “Coupled” and “connected” may also be used to indicate that two or more elements cooperate or interact with each other.
Please refer to
In structure, the system-on-a-chip SoC is coupled to the control circuit TCON, the control circuit TCON is coupled to the LCD panel LCD1 and the LCD panel LCD2. Specifically, the system-on-a-chip SoC is coupled to the timing controller 120 through a low-voltage differential signal receiving interface LVDS_Rx, the timing controller 120 is coupled to the LCD panel LCD1, the LCD panel LCD2 and the operational circuit 140, and the operational circuit 140 is coupled to the operational circuit 160. In addition, the timing controller 120 is coupled to the LCD panel LCD2 through a low-voltage differential signal transmitting interface Mini-LVDS2, the operational circuit 160 is coupled to the LCD panel LCD1 through a low-voltage differential signal transmitting interface Mini-LVDS1.
Operationally, the system-on-a-chip SoC outputs a low-voltage differential signal to timing controller 120 of the control circuit TCON through the low-voltage differential signal receiving interface LVDS_Rx of the control circuit TCON. The timing controller 120 output a clock signal to the LCD panel LCD1 and the LCD panel LCD2. On the other hand, the timing controller 120 transmits color data signals to the operational circuit 140 and the operational circuit 160, and performs operation according to a backlight signal processing method. The operational circuit 160 generates corresponding driving signals according to the operation results, and output the corresponding driving signals to the LCD panel LCD1 through the low-voltage differential signal transmitting interface Mini-LVDS1, so that the LCD panel LCD1 displays according to the corresponding driving signals. In addition, the timing controller 120 generates the corresponding driving signals according to the color data signals, and output the color data signals to the LCD panel LCD2 through the low-voltage differential signal transmitting interface Mini-LVDS2, so that the LCD panel LCD2 displays according to the driving signals corresponding to the color data signals.
In some embodiments, as shown in
In the present embodiment, the resolution of the LCD panel LCD1 is smaller than the resolution of the LCD panel LCD2. For example, as shown in
It should be noted that, the number or the size of the pixels and areas included by the LCD panel LCD1 and the LCD panel LCD2 may be adjusted based on the actual requirements, and
In this way, with the lower resolution LCD panel LCD1, the transmittance of the backlight source is able to be increased, therefore, under the same brightness requirements, the backlight brightness required by the backlight component BL is able to be scaled down, so that the backlight component BL is less likely to overheat. Furthermore, the lower resolution of the LCD panel LCD1 is able to reduce the amount of image data calculation and reduce the cost of hardware circuits.
In some embodiments, the LCD panel LCD1 and the LCD panel LCD2 may be a general flat panel or a curved panel, and the backlight component BL may be a general backlight component or a backlight component with local dimming. In some other embodiments, as shown in
In some embodiments, control circuit TCON may be realized by various processing circuit, a micro controller, a center processor, a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a complex programmable logic device (CPLD), a field-programmable gate array (FPGA) or logic circuit, etc.
About the detail of the backlight signal processing method, please refer to
Firstly, in operation S210, the operational circuit 140 receives the color data signals RGB, and performs calculation according to the color data signals RGB to generate the gray level data signals GL. Specifically, the total number of the pixels of the input image received by the display device 100 is equal to the number of the pixels of the LCD panel LCD2, and each pixel of the input image corresponds to one of the multiple color data signals RGB. Any one of the color data signals RGB includes a red data value, a green data value and a blue data value. The operational circuit 140 is configured to take the largest one of the red data value, the green data value and the blue data value to be a gray level data signal GL corresponding to the color data signal RGB. For example, when the color data signal RGB of the first pixel of the input image includes the red data value 56, the green data value 25 and the blue data value 230, the operational circuit 140 will take the blue data value 230 as the gray level data signal GL of the first pixel. In other words, through the operation S210, the operational circuit 140 converts the color input image into the gray-level image signal.
Next, in operation S220, the operational circuit 140 samples the gray level data signals to reduce the image resolution and transmits the lower resolution image signals to the operational circuit 160. Specifically, the operational circuit 140 converts the gray level data signals GL corresponding to the number of the pixels of the LCD panel LCD2 (e.g., 1920×720) into the gray level data signals GLs corresponding to the number of the areas of the LCD panel LCD1 (e.g., 640×240). The number of the areas of the LCD panel LCD1 is smaller than the number of the pixels of the LCD panel LCD2, that is, the number of the gray level data signals GLs is smaller than the number of the gray level data signals GL (i.e., the total number of the pixels of the input image).
Please refer to
To further illustrate, the operational circuit 140 selects first pixels from the outside to the inside in the X direction and the Y direction of the pixel matrix area SA, and copies their gray level values and fills in the mirrored pixel area SAn adjacent to the pixel matrix area SA. For example, if the widths of the row and the column of the mirrored pixel area SAn are both 2, then there are 8 pixels adjacent to the matrix position (1,1), so when the pixel gray level at the matrix position (1,1) is P11, then the 8 pixels may be filled into the gray level P11. It should be noted that the rows and columns of the pixels in the mirror image area may be designed according to actual requirements. In this embodiment, the widths of the rows and columns are both 2 as merely examples, not intended to limit the present disclosure.
In this way, by copying the gray level data signals of the surrounding area to generate a relatively enlarged virtual image, when the edges of the multiple spliced LCD panels are being calculated, the calculated values will not be biased high because they exceed the original input image range, so as to avoid the situation that bright lines appear on the splicing edge of the display device.
Then, the operational circuit 140 groups the gray level data signals GL in the virtual image according to different neighboring pixels (e.g., pixel groups U1 to U9 in
It should be noted that, the above averaging the gray level data signals GL to obtain the gray level data signals GLs is merely an example for illustration, and is not intended to limit the present disclosure. Those skilled in art may adjust according to actual requirements. For example, in some other embodiments, the 16 gray level data signals of the same pixel group may be multiplied by different weights according to different positions, and then be averaged to obtain the gray level data signal.
In this way, after operation S220, the operational circuit 140 converts the gray-level input image of the original resolution into a gray-level image signal of the lower resolution. Since the calculation in the present embodiment is simple, the operation cost will not be increased. In addition, since the image data signals corresponding to pixels are sampled with similar weights, all the brightness data in the image can be retained evenly, and will not disappear during the operation process due to the too small image details.
Next, please keep referring to
In operation S230, the operational circuit 160 determines whether the gray level data signals GLs are larger than or equal to a brightness threshold TH. When the gray level data signals GLs are larger than or equal to the brightness threshold TH, in operation S240, the operational circuit 160 adjusts the gray level data signals GLs to the maximum brightness value (e.g., 255), and in the operation S250a, the operational circuit 160 multiplies the maximum brightness value by a coefficient matrix Matrix1 to obtain the corresponding gray-level matrix. When the gray level data signals GLs are smaller than the brightness threshold TH, in operation S250b, the operational circuit 160 multiplies the gray level data signals GLs by a coefficient matrix Matrix2 to obtain the corresponding gray-level matrix.
Specifically, in the present disclosure, the coefficient matrix Matrix1 and the coefficient matrix Matrix2 are 5×5 matrixes, as shown in
For example, taking the brightness threshold TH as 15 as an example, as shown in
In other words, after operations S230, S240, S250a, and S250b, the operational circuit 160 will receive the scaled down gray level data signal GLs from the operational circuit 140 and generate a corresponding number of gray level matrices. It should be noted that the size, the overlapping distribution and sampling operation method of the pixel groups above, the value of the brightness threshold TH, and the number and value of the coefficients of the coefficient matrix Matrix1 and Matrix2 are only examples, and may be adjusted according to actual requirements, not intended to limit the present disclosure.
Next, in operation S260, the operational circuit 160 performs an overlapping (sum and shift) operation on the generated multiple gray-level matrices to obtain a backlight matrix. Specifically, the operational circuit 160 shifts the multiple gray-level matrices according to positions corresponding to their respective gray level data signals GLs, so that the respective center positions of the multiple gray-level matrices are located at the original gray level data signals GLs. The operational circuit 160 sums up the values at the same position to obtain the backlight matrices.
For example, the backlight matrix obtained from the input image IMG1 in
In this way, by the operational circuits 140 and 160 operating according to the backlight signal processing method, multiple color data signals RGB corresponding to the number of pixels of the LCD panel LCD2 are able to be converted into the backlight matrix corresponding to the number of areas of the LCD panel LCD1. And by controlling the LCD panel LCD1 and the LCD panel LCD2 to display respectively according to the backlight matrices and the color data signals RGB, the contrast is able to be effectively improved.
It should be noted that the total number or size of the pixels included in the input image IMG1 and the output image IMG2 may be adjusted according to actual requirements.
Please refer to
Further, as shown in
In some other embodiments, please refer to
It should be noted that the sequence of execution of the processes in the foregoing flowcharts is merely an exemplary embodiment, not intended to limit to the present disclosure. Various alterations and modifications may be performed on the disclosure by those of ordinary skills in the art without departing from the principle and spirit of the disclosure. In the foregoing, exemplary operations are included. However, these operations do not need to be performed sequentially. The operations mentioned in the embodiment may be adjusted according to actual needs unless the order is specifically stated, and may even be performed simultaneously or partially simultaneously.
It is noted that, the drawings, the embodiments, and the features and circuits in the various embodiments may be combined with each other as long as no contradiction appears. The circuits illustrated in the drawings are merely examples and simplified for the simplicity and the ease of understanding, but not meant to limit the present disclosure. In addition, those skilled in the art can understand that in various embodiments, circuit units may be implemented by different types of analog or digital circuits or by different chips having integrated circuits. Components may also be integrated in a single chip having integrated circuits. The description above is merely by examples and not meant to limit the present disclosure.
In summary, in various embodiments of the present disclosure, by performing calculations according to the backlight signal processing method, multiple color data signals RGB corresponding to the number of pixels of the LCD panel LCD2 can be converted into a backlight matrix corresponding to the number of areas of the LCD panel LCD1. By controlling the LCD panel LCD1 and the LCD panel LCD2 to display respectively according to the backlight matrix and the color data signals RGB, the contrast can be effectively improved.
Although specific embodiments of the disclosure have been disclosed with reference to the above embodiments, these embodiments are not intended to limit the disclosure. Various alterations and modifications may be performed on the disclosure by those of ordinary skills in the art without departing from the principle and spirit of the disclosure. Thus, the protective scope of the disclosure shall be defined by the appended claims.
Number | Date | Country | Kind |
---|---|---|---|
108119566 | Jun 2019 | TW | national |
Number | Name | Date | Kind |
---|---|---|---|
8698859 | DeLuca | Apr 2014 | B2 |
20070041054 | Kakutani | Feb 2007 | A1 |
20080108393 | Kim | May 2008 | A1 |
20080129677 | Li | Jun 2008 | A1 |
20090096710 | Raman | Apr 2009 | A1 |
20100328336 | Si | Dec 2010 | A1 |
20110037784 | Shiomi | Feb 2011 | A1 |
20120281028 | Orlick | Nov 2012 | A1 |
20120293399 | Haskin | Nov 2012 | A1 |
20160104412 | Su | Apr 2016 | A1 |
20160260198 | Hu et al. | Sep 2016 | A1 |
20170061896 | Zhang | Mar 2017 | A1 |
20170061897 | Zhang | Mar 2017 | A1 |
20170061901 | Zhang | Mar 2017 | A1 |
20170061902 | Zhang | Mar 2017 | A1 |
20170084232 | Yang | Mar 2017 | A1 |
20170110064 | Zhang | Apr 2017 | A1 |
20170110065 | Zhang | Apr 2017 | A1 |
20170212717 | Zhang | Jul 2017 | A1 |
20170358253 | Bonnier | Dec 2017 | A1 |
20180299726 | Oka | Oct 2018 | A1 |
20180308429 | Meng | Oct 2018 | A1 |
20190096341 | Zha | Mar 2019 | A1 |
20190130852 | Liao | May 2019 | A1 |
20190132489 | Liao | May 2019 | A1 |
20190348001 | Shi | Nov 2019 | A1 |
20200320941 | Ge | Oct 2020 | A1 |
20200320957 | Zhang | Oct 2020 | A1 |
20200357362 | Shin | Nov 2020 | A1 |
Number | Date | Country |
---|---|---|
1484453 | Mar 2004 | CN |
108761888 | Nov 2018 | CN |
Number | Date | Country | |
---|---|---|---|
20200388234 A1 | Dec 2020 | US |