Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
In order to more conveniently understand the technical solution provided by the embodiment of the present invention, a basic method for displaying an image by using an existing display device is first described. The conventional display device includes a display panel and a central processing unit, wherein the central processing unit generates an image frame and transmits the image frame to a source driver and a gate driver of the display panel, and the source driver and the gate driver of the display panel display an image of the image frame after receiving the image frame.
An embodiment of the present invention provides a brightness correction method, which is applied to a display device, where the display device includes a display panel and a backlight module, as shown in fig. 1, the display panel includes a first area 11 and a second area 12, where the second area 12 surrounds the first area 11. As shown in fig. 1, the first region 11 is preferably a region near an edge on the display panel 10. Illustratively, the resolution of the display panel is 1024 × 768, that is, the display panel includes 786432 pixels, and the first region may include 100 pixels. The second region 12 surrounds the first region 11 and may include 50 pixels. Of course, the number of pixels included in the first region and the second region may be set according to the size, resolution, and the like of the display panel, and the embodiment of the present invention will be described in detail only by taking an example in which the first region includes 100 pixels and the second region includes 50 pixels at the above-described resolution.
As shown in fig. 2, the luminance correction method includes:
step 101, acquiring a first gray-scale value of each pixel of a first area and/or a second area in a first image frame.
The first image frame may specifically be an image frame to be displayed, which is sent to the display panel by the processor. The first image frame includes a first gray-scale value for each pixel on the display panel. In general, the first gray-scale values of the pixels in the first region are not completely equal.
Step 102, determining the first area and the second area according to the first gray-scale value of each pixel of the first area and/or the second area, or only determining the second gray-scale value of each pixel of the first area. The second gray-scale values of the pixels in the first area and the second area or only the first area are equal.
The second gray-scale value is close to the first gray-scale value of each pixel in the first area and/or the second area. The second gray scale value may be a minimum gray scale value among the first gray scale values of the pixels in the first region and/or the second region, and may be a maximum gray scale value among the first gray scale values of the pixels in the first region and/or the second region.
Specifically, step 101 may be to acquire only the first gray scale value of each pixel of the first region, and step 102 may specifically be to determine the second gray scale value of each pixel of the first region and the second region according to the first gray scale value of each pixel of the first region; alternatively, step 102 may specifically be to determine the second gray-scale value of each pixel of the first region according to the first gray-scale value of each pixel of the first region.
Or, in step 101, only the first gray-scale value of each pixel of the second region may be obtained, and then, in step 102, the second gray-scale value of each pixel of the first region and each pixel of the second region may be determined according to the first gray-scale value of each pixel of the second region; alternatively, step 102 may specifically be to determine the second gray-scale value of each pixel of the first region according to the first gray-scale value of each pixel of the second region.
Or, in step 101, the first gray-scale values of the pixels in the first region and the second region may be obtained, and in step 102, the second gray-scale values of the pixels in the first region and the second region may be determined according to the first gray-scale values of the pixels in the first region and the second region; alternatively, step 102 may specifically be to determine the second gray-scale value of each pixel of the first region according to the first gray-scale value of each pixel of the first region and the second region.
The second gray scale values of the pixels in the first area and the second area, or only the first area, are all equal, that is, if the second gray scale value is 200, the pixels in the first area and the second area, or only the first area, all display 200 gray scales. In general, the first gray-scale values of the pixels in the first region and/or the second region are not completely equal.
Step 103, updating the first area and the second area with the second gray-scale value, or updating only the first gray-scale value of each pixel of the first area, so as to generate a second image frame.
The second image frame comprises first gray-scale values of all pixels of the first area and the second area and first gray-scale values of other pixels on the display panel; alternatively, the second image frame includes the first gray-scale value of each pixel of the first area and the first gray-scale values of other pixels on the display panel.
And 104, displaying the second image frame on the display panel.
The first area of the display panel displays the same gray scale because the second gray scale values of the pixels in the first area are all equal.
Step 105, detecting the actual brightness value of the first area.
As shown in fig. 11, detecting the actual brightness value of the first region 11 may be to provide a light sensor at a position corresponding to the first region 11 on the light emitting side of the display panel 10, and detect the brightness value of the first region 11 by the light sensor.
A general optical sensor includes a light-receiving surface, and the optical sensor can detect luminance information of light incident on the light-receiving surface, but since the light-receiving surface of the optical sensor cannot be infinitely close to the light-emitting surface of the display panel, it cannot detect only luminance information of a region of the display panel corresponding to the light-receiving surface of the optical sensor. The light emitted from the other region than the region interferes with the detection of the luminance information of the region, and in order to ensure the detection accuracy, the other region than the region needs to be set to the same gray scale value as the region.
In the embodiment of the invention, the area of the display screen corresponding to the light sensing surface of the light sensor is the first area. In order to accurately detect the luminance information of the first region, it is preferable in the embodiment of the present invention that the gray scale value of each pixel in the second region is equal to the gray scale value of each pixel in the first region.
As shown in fig. 1, the first region 11 is surrounded by the second region 12, and the first region 11 is located at the center of the second region 12. Therefore, in step 102, preferably, a second gray-scale value of each pixel of the first region and the second region is determined according to the first gray-scale value of each pixel of the first region and/or the second region, and step 103 is to update the first gray-scale value of each pixel of the first region and the second region with the second gray-scale value, so as to generate the second image frame. That is, the second image frame includes the first gray-scale values of the pixels of the first area and the second area, and the first gray-scale values of the other pixels on the display panel. Therefore, the second gray-scale values of the pixels in the first area and the second area are equal, and the brightness of the first area detected by the light sensing device is more accurate.
And 106, adjusting the brightness of the backlight module according to the actual brightness value and the target brightness value of the first area.
The target brightness value is a brightness value corresponding to each pixel of the backlight module in the first area under the preset backlight brightness and displaying the second gray scale value. The actual brightness value is the brightness value of each pixel in the first area of the backlight module displaying the second gray scale value under the actual backlight brightness.
As shown in fig. 3, step 106 specifically includes:
step 1061, comparing the actual brightness value with the target brightness value.
Step 1062, reducing the brightness of the backlight module when the actual brightness value is greater than the target brightness value; or, under the condition that the actual brightness value is smaller than the target brightness value, the brightness of the backlight module is increased.
Specifically, the preset backlight brightness may be a brightness of the backlight module after the display panel is manufactured and formed when the light emitting device is not used and is not attenuated. With the use of the display device, the luminous efficiency of the light emitting device of the backlight module is reduced, so that the actual backlight brightness of the backlight module is lower than the preset backlight brightness, and the brightness of the backlight module needs to be increased after the display device is used for a certain time.
Specifically, taking a light emitting device in the backlight module as an LED as an example, increasing the luminance of the backlight module may be increasing the driving current value of the LED, thereby improving the light emitting efficiency of the LED and adjusting the backlight luminance of the backlight module.
It should be noted that the target brightness value may be a brightness value of each pixel in the first area of the backlight module displaying the second gray scale value under the preset backlight brightness. The actual brightness value is the brightness value of each pixel in the first area of the backlight module displaying the second gray scale value under the actual backlight brightness. In this case, if the gray scale division levels of the gray scale values of the pixels displayed on the display panel are all 0 to 4096 levels, the preset luminance value may be 4097 gray scale values corresponding to the second gray scale values of 0 to 4096 levels, respectively. The actual brightness value may also be 4097 gray-scale values corresponding to the second gray-scale values being respectively 0-4096 levels.
Illustratively, the step 101 is to obtain a first gray-scale value of each pixel of the first region and the second region in the first image frame. Step 102 specifically determines that the second gray-scale value of each pixel in the first region is 3200 according to the first gray-scale values of each pixel in the first region and the second region. The actual brightness value is the brightness value of 3200 steps displayed by each pixel in the first area of the backlight module under the actual backlight brightness, for example, 250 nit. The target brightness value is the brightness value of 3200 steps displayed by each pixel in the first area of the backlight module under the preset backlight brightness, and is 300nit, for example. Then, since the actual brightness value is smaller than the target brightness value, the brightness of the backlight module needs to be increased.
Of course, 4097 target luminance values determined corresponding to orders 0-4096 may form a look-up table. Comparing the actual brightness value with the target brightness value can be searching and comparing with the lookup table, and then adjusting the brightness of the backlight module according to the comparison result.
The embodiment of the invention provides a brightness correction method, which is used for acquiring a first gray-scale value of each pixel of a first area and/or a second area on a display panel in a first image frame when the brightness of a display device is adjusted, and then determining the first area and the second area according to the first gray-scale value of each pixel of the first area and/or the second area, or only determining a second gray-scale value of each pixel of the first area, wherein the second gray-scale values of each pixel of the first area and the second area, or only the first area are equal. The second image frame is displayed on the display panel and an actual brightness value of the first region is detected. At this time, since the second gray scale value is close to the first gray scale value of each pixel of the first region and/or the second region, the second gray scale value may be greater than or equal to the minimum gray scale value among the first gray scale values of each pixel of the first region and/or the second region, and less than or equal to the maximum gray scale value among the first gray scale values of each pixel of the first region and/or the second region. The user will not substantially perceive the display of the first region as being different from the display of its surrounding region (e.g., the second region), so that the entire luminance correction process will not affect the normal display, improving the user experience.
Preferably, as shown in fig. 4, the step 102 specifically includes:
step 1021, determining a basic gray-scale value according to the first gray-scale value of each pixel of the first area and/or the second area. The basic gray-scale value is greater than or equal to the minimum gray-scale value in each pixel of the first area and/or the second area and less than or equal to the maximum gray-scale value in each pixel of the first area and/or the second area.
Preferably, the basic gray-scale value is an average value of the first gray-scale values of the pixels of the first region and/or the second region. Or the basic gray-scale value is the most gray-scale value in the first gray-scale values of the pixels in the first area and/or the second area. Thus, when the first region and the second region, or only each pixel of the first region, display the second gray scale value, the display gray scale value is closer to the display gray scale value of the first gray scale value displayed by each pixel of the first region and/or the second region, and the user does not basically perceive the difference between the display of the first region and the display of the surrounding region.
Step 1022, determine the basic gray-scale value as the first region and the second region, or only as the second gray-scale value of each pixel of the first region.
For example, in step 101, to obtain first gray scale values of pixels in the first region and the second region, step 102 specifically determines second gray scale values of the first region according to the first gray scale values of pixels in the first region and the second region. The average value of the first grayscale values of 100 pixels included in the first region and the first grayscale values of 50 pixels included in the second region is 200 (that is, the average value of the first grayscale values of 150 pixels in the first region and the second region is 200), and then it is determined that the second grayscale values of the pixels in the first region are 200.
Or, if the first grayscale values of 120 pixels of the 150 pixels in the first region and the second region are both 200, it is determined that the second grayscale values of the pixels in the first region and the second region are both 200.
Still alternatively, the first gray-scale values of the pixels in the first region and the second region obtained in step 101 are both equal, for example, both equal to 200. The first region and the second region are determined or only the second gray scale value of each pixel of the first region is determined to be 200. At this time, the average value of the first gray-scale values of the pixels in the first area and the second area is 200, which corresponds to a basic gray-scale value of 200.
It should be noted that, in step 103, the first region and the second region are updated with the second gray scale value, or only the first gray scale value of each pixel in the first region is updated, which may be controlled and generated by the OSD generator. Since the display of the first region and the second region, or only the pixels of the first region, is used to detect the brightness of the first region, the general OSD generator controls the generated first region and second region, or only the gray-scale division level of the second gray-scale value of the pixels of the first region to be smaller than the gray-scale division level of the first gray-scale value of the pixels in the first image frame.
For example, the first gray scale value of each pixel on the display panel in the first image frame has a gray scale division level of 0-4096, and the OSD generator controls the second gray scale value of the first region to be updated to have a gray scale division level of 0-255. That is, the first gray scale value corresponding to the pixel displaying white in the first image frame is 4096, and the first region and the second region generated by the OSD generator in the second image frame, or the second gray scale value corresponding to the pixel displaying white only in each pixel of the first region generated by the OSD generator is 255, and the first gray scale value corresponding to the pixel displaying white in each pixel of the other regions is still 4096.
The first region and the second region updated by the OSD generator in the second image frame, or the OSD generator updates only the gray scale division level of the second gray scale value of each pixel of the first region is not equal to the gray scale division level of the first gray scale value of each pixel of the first region and/or the second region in the first image frame.
Optionally, after the step 101 and before the step 104, the brightness correction method further includes:
and step 107, determining a second gray scale value corresponding to the first gray scale value according to the corresponding relation between the gray scale division level of the first gray scale value of each pixel in the first image frame and the gray scale division level of the second gray scale value of each pixel in the updated first area and the updated second area in the second image frame, or the gray scale division level of each pixel in the updated first area only.
Illustratively, the first gray scale value of each pixel on the display panel in the first image frame has a gray scale division level of 0-4096 steps, and the OSD generator controls the generated second gray scale value to have a gray scale division level of 0-255 steps.
As shown in fig. 5, the luminance correction method includes:
step 101, obtaining a first gray-scale value of each pixel of the first area and the second area.
And 102, determining a second gray-scale value of each pixel of the first area according to the first gray-scale values of each pixel of the first area and the second area.
Illustratively, the average value of the first gray-scale values of the pixels of the first and second regions is 3200.
Step 107, determining a second gray scale value corresponding to the first gray scale value according to the corresponding relationship between the gray scale division level of the first gray scale value of each pixel in the first image frame and the gray scale division level of the second gray scale value of each pixel in the first area updated in the second image frame.
The correspondence relationship between the gray scale division level of the first gray scale value of each pixel in the first image frame and the gray scale division level of the second gray scale value of each pixel in the updated first region in the second image frame may be a lookup table as shown in fig. 6. Wherein G1 is a first gray-scale value of each pixel in the first image frame, and G2 is a second gray-scale value of each pixel in the updated first region. As shown in fig. 6, the gray scale division level of the gray scale value of G1 is 0 to 4096 levels, the gray scale division level of the gray scale value of G2 is 0 to 255 levels, and the second gray scale value corresponding to the average 3200 of the first gray scale values of the pixels in the first region and the pixels in the second region is 200.
Step 103, updating the first gray-scale value of each pixel in the first area with the second gray-scale value so as to generate a second image frame.
The second gray scale value of each pixel of the first region and the second region in the second image frame is 200.
And 104, displaying the second image frame on the display panel.
Step 105, detecting the actual brightness value of the first area.
And 106, adjusting the brightness of the backlight module according to the actual brightness value and the target brightness value of the first area.
In practice, to improve the accuracy of the brightness of the display panel, the brightness value in the white field is detected. For example, if the gray scale division level of the display panel is 0 to 4096 levels, 4096 levels correspond to white display, and the brightness of the display panel is detected to be the brightness value of 4096 levels displayed by each pixel in the first region. However, the white field displayed in the first area may make the display of the first area different from that of the other areas, and the white field in the first area may be particularly conspicuous and dazzling, thereby affecting the normal display and reducing the customer experience.
In order to make the brightness correction of the display panel more accurate, in the embodiment of the present invention, although the actual brightness value of the first region is detected in step 105 and is not obtained in the white field, the actual brightness in step 106 is down-converted to the target brightness value, so that the accuracy of the correction is improved without the user substantially perceiving the difference between the display of the first region and the display of the other regions.
The following is described in two ways:
the first method is as follows: the target brightness value is the brightness value of the backlight module displaying the full white field in the first area under the preset backlight brightness.
As shown in fig. 7, step 106 specifically includes:
step 106a1, obtaining a first reference brightness value according to the actual brightness value. The first reference brightness value is a brightness value of the first area displaying a full white field under actual backlight brightness.
Step 106a2, comparing the first reference brightness value with the target brightness value.
Step 106a3, reducing the brightness of the backlight module when the first reference brightness value is greater than the target brightness value; or, under the condition that the first reference brightness value is smaller than the target brightness value, the brightness of the backlight module is increased.
Preferably, the actual luminance value and the first reference luminance value satisfy the following relationship:
wherein Ls is a first reference luminance value, Lx is an actual luminance value, M is a gray scale value of all white displayed by each pixel of the first region, Gamma is a curvature of a Gamma compensation curve in the display device, and n is a second gray scale value of each pixel of the first region, wherein a gray scale division level of the second gray scale value of each pixel of the first region is equal to a gray scale division level of the gray scale value of each pixel of the first region.
For example, the curvature of the Gamma compensation curve in the display device is 2.2; each pixel of the first area displays a full white gray scale value of 4096; each pixel in the first area displays a second gray scale value of 200 gray scales, which corresponds to a gray scale value of 3200 from 0 to 4096 levels; the actual luminance value and the first reference luminance value satisfy the following relationship:
the second method comprises the following steps: the target brightness value is the brightness value of the backlight module displaying the full white field in the first area under the preset backlight brightness.
As shown in fig. 8, step 106 specifically includes:
and step 106b1, acquiring a second reference brightness value according to the target brightness value. The second reference brightness value is a brightness value of each pixel in the first area of the backlight module displaying the second gray scale value under the preset backlight brightness.
Step 106b2, comparing the actual luminance value with the second reference luminance value.
Step 106b3, reducing the brightness of the backlight module when the actual brightness value is larger than the second reference brightness value; or, under the condition that the actual brightness value is smaller than the second reference brightness value, the brightness of the backlight module is increased.
Preferably, the target luminance value and the second reference luminance value satisfy the following relationship:
where Lb is a second reference luminance value, La is a target luminance value, M is a full-white gray scale value displayed by each pixel in the first region, Gamma is a curvature of a Gamma compensation curve in the display device, and n is a second gray scale value of each pixel in the first region, where a gray scale division level of the second gray scale value of each pixel in the first region is equal to a gray scale division level of the gray scale value of each pixel in the first region, which may specifically refer to the description in step 106a3, and details are not repeated here.
In the following, the embodiment of the present invention provides a luminance correcting apparatus corresponding to the luminance correcting method in the embodiment of the present invention, it should be noted that each functional unit included in the following apparatus can execute the corresponding steps in the above method, so that the detailed description of each functional unit of the apparatus is not provided in the following embodiment.
The embodiment of the invention provides a brightness correction device which is applied to display equipment, wherein the display equipment comprises a display panel, the display panel comprises a first area and a second area, and the second area surrounds the first area; as shown in fig. 9, the luminance correcting apparatus includes:
the acquiring unit 101 is configured to acquire a first gray-scale value of each pixel of a first region and/or a second region in a first image frame.
Specifically, the acquisition unit may be a source driver and a gate driver of the display panel.
The first determining unit 102 is configured to determine the first region and the second region according to the first gray scale value of each pixel of the first region and/or the second region, or determine only the second gray scale value of each pixel of the first region.
A processing unit 103 for updating the first area and the second area with the second gray-scale value, or updating only the first gray-scale value of each pixel of the first area, so as to generate a second image frame.
A display unit 104 for displaying the second image frame on the display panel.
A detection unit 105 for detecting an actual luminance value of the first area.
Specifically, the detection unit may be a photosensor disposed at the light exit side of the display panel to correspond to the first region.
The adjusting unit 106 is configured to adjust the brightness of the backlight module according to the actual brightness value and the target brightness value of the first region.
Preferably, as shown in fig. 10, the first determining unit 102 specifically includes:
the first determining module 1021 is configured to determine a basic gray-scale value according to the first gray-scale value of each pixel of the first area and/or the second area. The basic gray-scale value is greater than or equal to the minimum gray-scale value in each pixel of the first area and/or the second area and less than or equal to the maximum gray-scale value in each pixel of the first area and/or the second area.
A second determining module 1022, configured to determine the basic grayscale value as the first region and the second region, or only as the second grayscale value of each pixel of the first region.
It should be noted that the processing unit 103 may be an OSD generator. Since the display of the first region and the second region, or only the pixels of the first region, is used to detect the brightness of the first region, the general OSD generator controls the generated first region and second region, or only the gray-scale division level of the second gray-scale value of the pixels of the first region to be smaller than the gray-scale division level of the first gray-scale value of the pixels in the first image frame.
For example, the first gray scale value of each pixel on the display panel in the first image frame has a gray scale division level of 0-4096, and the OSD generator controls the second gray scale value of the first region to be updated to have a gray scale division level of 0-255. That is, the first gray scale value corresponding to the pixel displaying white in the first image frame is 4096, and the first region and the second region generated by the OSD generator in the second image frame, or the second gray scale value corresponding to the pixel displaying white only in each pixel of the first region generated by the OSD generator is 255, and the first gray scale value corresponding to the pixel displaying white in each pixel of the other regions is still 4096.
In the case where the first region and the second region updated by the OSD generator in the second image frame or the OSD generator updates only the gray scale division level of the second gray scale value of each pixel of the first region is not equal to the gray scale division level of the first gray scale value of each pixel of the first region and/or the second region in the first image frame, the luminance correcting apparatus further includes:
the second determining unit 107 is configured to determine a second gray scale value corresponding to the first gray scale value according to a corresponding relationship between a gray scale division level of the first gray scale value of each pixel in the first image frame and a gray scale division level of a second gray scale value of each pixel in the second image frame, or a gray scale division level of a second gray scale value of each pixel in the first area that is updated only.
Illustratively, the first gray scale value of each pixel on the display panel in the first image frame has a gray scale division level of 0-4096 steps, and the OSD generator controls the generated second gray scale value to have a gray scale division level of 0-255 steps.
As shown in fig. 11, the luminance correcting apparatus includes:
an obtaining unit 101 is configured to obtain a first gray-scale value of each pixel of the first region and the second region.
The first determining unit 102 is configured to determine a second gray-scale value of each pixel of the first region according to the first gray-scale value of each pixel of the first region and the second region.
Illustratively, the average value of the first gray-scale values of the pixels of the first and second regions is 3200.
The second determining unit 107 is configured to determine a second gray scale value corresponding to the first gray scale value according to a corresponding relationship between a gray scale division level of the first gray scale value of each pixel in the first image frame and a gray scale division level of the second gray scale value of each pixel in the updated first region in the second image frame.
The correspondence relationship between the gray scale division level of the first gray scale value of each pixel in the first image frame and the gray scale division level of the second gray scale value of each pixel in the updated first region in the second image frame may be a lookup table as shown in fig. 6. Wherein G1 is a first gray-scale value of each pixel in the first image frame, and G2 is a second gray-scale value of each pixel in the updated first region. As shown in fig. 6, the gray scale division level of the gray scale value of G1 is 0 to 4096 levels, the gray scale division level of the gray scale value of G2 is 0 to 255 levels, and the second gray scale value corresponding to the average 3200 of the first gray scale values of the pixels in the first region and the pixels in the second region is 200.
The processing unit 103 is configured to update the first gray-scale value of each pixel in the first area with the second gray-scale value, so as to generate a second image frame. The second gray scale value of each pixel of the first region and the second region in the second image frame is 200.
A display unit 104 for displaying the second image frame on the display panel.
A detection unit 105 for detecting an actual luminance value of the first area.
The adjusting unit 106 is configured to adjust the brightness of the backlight module according to the actual brightness value and the target brightness value of the first region.
Preferably, the target brightness value is a brightness value corresponding to each pixel in the first area of the backlight module displaying the second gray scale value under the preset backlight brightness; as shown in fig. 12, the adjusting unit 106 specifically includes:
the first comparing module 1061 is configured to compare the actual brightness value with the target brightness value.
The second processing module 1062 is configured to reduce the brightness of the backlight module when the actual brightness value is greater than the target brightness value; or, under the condition that the actual brightness value is smaller than the target brightness value, the brightness of the backlight module is increased.
Specifically, the preset backlight brightness may be a brightness of the backlight module after the display panel is manufactured and formed when the light emitting device is not used and is not attenuated. With the use of the display device, the luminous efficiency of the light emitting device of the backlight module is reduced, so that the actual backlight brightness of the backlight module is lower than the preset backlight brightness, and the brightness of the backlight module needs to be increased after the display device is used for a certain time.
Specifically, taking a light emitting device in the backlight module as an LED as an example, increasing the luminance of the backlight module may be increasing the driving current value of the LED, thereby improving the light emitting efficiency of the LED and adjusting the backlight luminance of the backlight module.
It should be noted that the target brightness value may be a brightness value of each pixel in the first area of the backlight module displaying the second gray scale value under the preset backlight brightness. The actual brightness value is the brightness value of each pixel in the first area of the backlight module displaying the second gray scale value under the actual backlight brightness. In this case, if the gray scale division levels of the gray scale values of the pixels displayed on the display panel are all 0 to 4096 levels, the preset luminance value may be 4097 gray scale values corresponding to the second gray scale values of 0 to 4096 levels, respectively. The actual brightness value may also be 4097 gray-scale values corresponding to the second gray-scale values being respectively 0-4096 levels.
Illustratively, the step 101 is to obtain a first gray-scale value of each pixel of the first region and the second region in the first image frame. Step 102 specifically determines that the second gray-scale value of each pixel in the first region is 3200 according to the first gray-scale values of each pixel in the first region and the second region. The actual brightness value is the brightness value of 3200 steps displayed by each pixel in the first area of the backlight module under the actual backlight brightness, for example, 250 nit. The target brightness value is the brightness value of 3200 steps displayed by each pixel in the first area of the backlight module under the preset backlight brightness, and is 300nit, for example. Then, since the actual brightness value is smaller than the target brightness value, the brightness of the backlight module needs to be increased.
Of course, 4097 target luminance values determined corresponding to orders 0-4096 may form a look-up table. Comparing the actual brightness value with the target brightness value can be searching and comparing with the lookup table, and then adjusting the brightness of the backlight module according to the comparison result.
Preferably, the target brightness value is a brightness value of a full white field displayed in a first area of the backlight module under the preset backlight brightness; as shown in fig. 13, the adjusting unit 106 specifically includes:
the first obtaining module 106a1 is configured to obtain a first reference brightness value according to the actual brightness value. The first reference brightness value is a brightness value of the first area displaying a full white field under actual backlight brightness.
The second comparing module 106a2 is used for comparing the first reference brightness value with the target brightness value.
The second processing module 106a3, configured to reduce the brightness of the backlight module when the first reference brightness value is greater than the target brightness value; or, under the condition that the first reference brightness value is smaller than the target brightness value, the brightness of the backlight module is increased.
Preferably, the actual luminance value and the first reference luminance value satisfy the following relationship:
wherein Ls is a first reference luminance value, Lx is an actual luminance value, M is a gray scale value of all white displayed by each pixel of the first region, Gamma is a curvature of a Gamma compensation curve in the display device, and n is a second gray scale value of each pixel of the first region, wherein a gray scale division level of the second gray scale value of each pixel of the first region is equal to a gray scale division level of the gray scale value of each pixel of the first region.
Preferably, the target brightness value is a brightness value of the backlight module displaying full white in the first area under the preset brightness; as shown in fig. 14, the adjusting unit 106 specifically includes:
the second obtaining module 106b1 is configured to obtain a second reference brightness value according to the target brightness value. The second reference brightness value is a brightness value of each pixel in the first area of the backlight module displaying the second gray scale value under the preset backlight brightness.
A third comparing module 106b2 for comparing the actual luminance value with the second reference luminance value.
The third processing module 106b32, configured to reduce the brightness of the backlight module when the actual brightness value is greater than the second reference brightness value; or, under the condition that the actual brightness value is smaller than the second reference brightness value, the brightness of the backlight module is increased.
Preferably, the target luminance value and the second reference luminance value satisfy the following relationship:
wherein Lb is a second reference luminance value, La is a target luminance value, M is a gray scale value of all white displayed by each pixel of the first region, Gamma is a curvature of a Gamma compensation curve in the display device, and n is a second gray scale value of each pixel of the first region, wherein a gray scale division level of the second gray scale value of each pixel of the first region is equal to a gray scale division level of the gray scale value of each pixel of the first region.
The embodiment of the invention provides display equipment comprising any one of the brightness correction devices provided by the embodiment of the invention. The display device may be a display device such as a liquid crystal display, an electronic paper, an OLED (Organic Light-Emitting Diode) display, and any product or component having a display function, such as a television, a digital camera, a mobile phone, and a tablet computer, which includes the display device.
Those of ordinary skill in the art will understand that: all or part of the steps for implementing the method embodiments may be implemented by hardware related to program instructions, and the program may be stored in a computer readable storage medium, and when executed, the program performs the steps including the method embodiments; and the aforementioned storage medium includes: various media that can store program codes, such as ROM, RAM, magnetic or optical disks.
The above description is only for the specific embodiments of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present invention, and all the changes or substitutions should be covered within the scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the appended claims.