CN112506455A

CN112506455A - Display method and device of to-be-projected screen, electronic equipment and readable storage medium

Info

Publication number: CN112506455A
Application number: CN202011298027.5A
Authority: CN
Inventors: 崔志佳; 谭森; 范泽华; 周翔翔
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2020-11-18
Filing date: 2020-11-18
Publication date: 2021-03-16

Abstract

The application relates to a display method and device of a picture to be projected, electronic equipment and a computer readable storage medium, which respond to a screen projection instruction and receive the picture to be projected sent by main equipment. And under the condition that the display color temperatures of the master device and the slave device are not consistent, adjusting the maximum brightness threshold of each color channel on the slave device according to the maximum brightness threshold of each color channel on the master device and the maximum brightness threshold of each color channel on the slave device to obtain the target brightness threshold of each color channel on the slave device. And adjusting the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave equipment according to the target brightness threshold value of each color channel on the slave equipment, the maximum brightness threshold value of each color channel on the master equipment and the gray-scale value of each color channel of each pixel on the master equipment. And displaying on the slave equipment to generate a screen projection picture based on the adjusted gray-scale value of each color channel of each pixel.

Description

Display method and device of to-be-projected screen, electronic equipment and readable storage medium

Technical Field

The present application relates to the field of computer technologies, and in particular, to a method and an apparatus for displaying a screen to be projected, an electronic device, and a readable storage medium.

Background

At present, the screen projection function is widely applied to electronic devices, and by establishing a communication connection between a master device and a slave device, content to be displayed can be transmitted to the slave device based on the master device so as to be displayed on the slave device. It is greatly convenient for a user to be able to view the display content on another device, such as is commonly used in a conference scenario.

However, if the difference in color between the master device and the slave device for projection is large, the color after projection cannot well restore the display effect of the master device, and the color restoration degree between the master device and the slave device is poor.

Disclosure of Invention

The embodiment of the application provides a display method and device of a picture to be projected, an electronic device and a readable storage medium, which can improve the color reduction degree of the picture to be projected.

A display method of a picture to be projected comprises the following steps:

responding to a screen projection instruction, and receiving a screen to be projected sent by the main equipment;

under the condition that the display color temperatures of the master device and the slave device are determined to be inconsistent, adjusting the maximum brightness threshold of each color channel on the slave device according to the maximum brightness threshold of each color channel on the master device and the maximum brightness threshold of each color channel on the slave device to obtain a target brightness threshold of each color channel on the slave device;

adjusting each color channel gray-scale value of each pixel when the picture to be projected is displayed on the slave device according to the target brightness threshold value of each color channel on the slave device, the maximum brightness threshold value of each color channel on the master device and each color channel gray-scale value of each pixel on the master device;

and displaying on the slave equipment to generate a screen projection picture based on the adjusted gray-scale value of each color channel of each pixel.

A display device of a picture to be projected, the device comprising:

the screen to be projected receiving module is used for responding to the screen projecting instruction and receiving the screen to be projected sent by the main equipment;

the brightness threshold adjusting module is used for adjusting the maximum brightness threshold of each color channel on the slave equipment according to the maximum brightness threshold of each color channel on the master equipment and the maximum brightness threshold of each color channel on the slave equipment under the condition that the display color temperatures of the master equipment and the slave equipment are determined to be inconsistent, so as to obtain the target brightness threshold of each color channel on the slave equipment;

the gray-scale value adjusting module is used for adjusting each color channel gray-scale value of each pixel when the picture to be projected is displayed on the slave device according to the target brightness threshold value of each color channel on the slave device, the maximum brightness threshold value of each color channel on the master device and each color channel gray-scale value of each pixel on the master device;

and the display module is used for displaying on the slave equipment to generate a screen projection picture based on the adjusted gray-scale value of each color channel of each pixel.

An electronic device comprises a memory and a processor, wherein the memory stores a computer program, and when the computer program is executed by the processor, the processor executes the steps of the display method of the screen to be projected.

A computer-readable storage medium, on which a computer program is stored which, when being executed by a processor, carries out the steps of the method for displaying a picture to be projected as described above.

The display method and device for the screen to be projected, the electronic device and the computer readable storage medium respond to the screen projection instruction and receive the screen to be projected sent by the main device. And under the condition that the display color temperatures of the master device and the slave device are not consistent, adjusting the maximum brightness threshold of each color channel on the slave device according to the maximum brightness threshold of each color channel on the master device and the maximum brightness threshold of each color channel on the slave device to obtain the target brightness threshold of each color channel on the slave device. And adjusting the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave equipment according to the target brightness threshold value of each color channel on the slave equipment, the maximum brightness threshold value of each color channel on the master equipment and the gray-scale value of each color channel of each pixel on the master equipment. And displaying on the slave equipment to generate a screen projection picture based on the adjusted gray-scale value of each color channel of each pixel.

Because the maximum brightness threshold value of each color channel on the slave device is adjusted, the target brightness threshold value of each color channel on the slave device is obtained. And then adjusting the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave equipment based on the target brightness threshold value of each color channel on the slave equipment, the maximum brightness threshold value of each color channel on the master equipment and the gray-scale value of each color channel of each pixel on the master equipment. Therefore, the color temperature of the screen projection picture displayed on the slave equipment is approximate to that of the screen to be projected on the master equipment, and the color restoration degree of the screen to be projected is improved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a diagram illustrating an exemplary embodiment of an application environment for a method for displaying a screen to be projected;

FIG. 2 is a flowchart illustrating a method for displaying a screen to be projected according to an embodiment;

FIG. 3 is a diagram illustrating a display signal processing process during a screen projection process according to an embodiment;

FIG. 4 is a flowchart of the method for adjusting the maximum luminance threshold of each color channel on the slave device in FIG. 2 to obtain the target luminance threshold of each color channel on the slave device;

fig. 5 is a schematic diagram illustrating a method for adjusting the maximum luminance threshold of each color channel on the slave device according to the first luminance threshold ratio and the second luminance threshold ratio to obtain the target luminance threshold of each color channel on the slave device in one embodiment;

FIG. 6 is a schematic diagram illustrating a method for adjusting gray-scale values of color channels of each pixel of the image to be projected in FIG. 2 when the image is displayed on a slave device;

FIG. 7A is a schematic diagram showing a Gamma curve for a certain color channel of device A;

FIG. 7B is a schematic diagram showing Gamma curves for a certain color channel of devices A and B;

FIG. 8 is a block diagram of a display device for displaying a screen to be projected according to an embodiment;

FIG. 9 is a block diagram of the brightness threshold adjustment module shown in FIG. 8;

fig. 10 is a schematic diagram of an internal structure of an electronic device in one embodiment.

Detailed Description

In order to make the objects, technical solutions and advantages of the present application more apparent, the present application is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the present application and are not intended to limit the present application.

Fig. 1 is an application scene diagram of a display method of a picture to be projected in one embodiment. As shown in fig. 1, the application environment includes an electronic device 120 (also referred to as a master device) and an electronic device 140 (also referred to as a slave device). The master device 120 and the slave device 140 may communicate with each other through a wired or wireless network, and the master device 120 may send a screen to be projected displayed on the master device 120 to the slave device 140 for displaying. The slave device 140 responds to the screen projection instruction by the display method of the screen to be projected in the application, and receives the screen to be projected sent by the master device; under the condition that the display color temperatures of the master device and the slave device are determined to be inconsistent, adjusting the maximum brightness threshold of each color channel on the slave device according to the maximum brightness threshold of each color channel on the master device and the maximum brightness threshold of each color channel on the slave device to obtain the target brightness threshold of each color channel on the slave device; adjusting each color channel gray-scale value of each pixel when a picture to be projected is displayed on the slave equipment according to the target brightness threshold value of each color channel on the slave equipment, the maximum brightness threshold value of each color channel on the master equipment and each color channel gray-scale value of each pixel on the master equipment; and displaying on the slave equipment to generate a screen projection picture based on the adjusted gray-scale value of each color channel of each pixel. Here, the master device 120 and the slave device 140 may be any terminal devices such as a mobile phone, a tablet computer, a PDA (Personal Digital Assistant), a wearable device, and a smart home, and the display screen area size of the master device 120 and the slave device 140 is not limited.

FIG. 2 is a flowchart illustrating a method for displaying a screen to be projected according to an embodiment. The display method of the screen to be projected in this embodiment is described by taking the slave device 140 in fig. 1 as an example. As shown in fig. 2, the display method of the to-be-projected picture includes steps 220 to 280. Wherein the content of the first and second substances,

and step 220, responding to the screen projection instruction, and receiving a screen to be projected sent by the main equipment.

The master device provides a screen to be projected, and the screen to be projected needs to be sent to the slave device for screen projection display. The slave device is a device for receiving the screen to be projected sent by the master device and displaying the screen to be projected. The screen projection instruction refers to an instruction which is sent to the slave device by the master device and needs to send a screen to be projected of the master device to the slave device for screen projection display, and the instruction carries the screen to be projected on the master device. The screen to be projected refers to content displayed on a display screen of the main device, including content such as images and characters, which is not limited in the present application.

The slave equipment receives a screen projection instruction sent by the master equipment, responds to the screen projection instruction, and receives a screen to be projected sent by the master equipment.

And 240, under the condition that the display color temperatures of the master device and the slave device are determined to be inconsistent, adjusting the maximum brightness threshold of each color channel on the slave device according to the maximum brightness threshold of each color channel on the master device and the maximum brightness threshold of each color channel on the slave device to obtain the target brightness threshold of each color channel on the slave device.

The color temperature is a unit of measure representing a color component contained in the light. Theoretically, color temperature refers to the color that an absolute black body would appear after it has been warmed from absolute zero degrees. After the black body is heated, the black body gradually turns red from black, turns yellow, turns white and finally emits blue light, and when the black body is heated to a certain temperature, the spectral components contained in the light emitted by the black body are called as the color temperature at the temperature. The concept of down-time color temperature has been widely used in electronic devices having display screens. The user selects a proper color temperature by adjusting the color temperature of the display screen of the electronic equipment, so that the damage to human eyes can be avoided, and the working efficiency or entertainment experience can be effectively improved.

When a screen to be projected sent by the master device is projected to the slave device to form a screen projection screen, if the display color temperatures of the master device and the slave device are not consistent, the color reduction degrees of the screen to be projected and the screen projection screen seen by a user are different, that is, the display effects are different. For example, if the display effect of the screen to be projected is normal, the display effect of the screen to be projected may be yellow or blue.

Generally, an electronic device includes three color channels, for example, three color channels of red, green, and blue, which are abbreviated as RGB three color channels. The maximum brightness threshold of each color channel on the main device refers to the maximum brightness threshold of the three RGB color channels on the main device. For an 8-bit display, when the gray scale value of the RGB three color channels is 255, the luminance corresponding to the RGB three color channels at this time is the maximum luminance threshold of the RGB three color channels on the display. In this way, the maximum luminance threshold of each color channel on the host device can be obtained. The same is true for the slave device, and the maximum brightness threshold of each color channel on the slave device is obtained.

Then, under the condition that it is determined that the display color temperatures of the master device and the slave device are not consistent, if it is desired that the display effects of the to-be-projected picture and the to-be-projected picture are consistent, the display parameters of the slave device need to be adjusted, so that the display effects of the to-be-projected picture and the to-be-projected picture are consistent, and the color reproduction degree is improved. Specifically, the maximum brightness threshold of each color channel on the slave device may be adjusted according to the maximum brightness threshold of each color channel on the master device and the maximum brightness threshold of each color channel on the slave device, so as to obtain the target brightness threshold of each color channel on the slave device. The ratio of the target brightness threshold value of each color channel on the slave device is equal to the ratio of the maximum brightness threshold value of each color channel on the master device or the difference between the target brightness threshold value and the maximum brightness threshold value is within a preset range. Because when the ratio of the maximum brightness threshold values of the color channels on different devices is the same or the difference between the maximum brightness threshold values is within a preset range, the color reduction degree between the display pictures on the two different devices is higher, and the display effect is consistent or close.

And step 260, adjusting the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave device according to the target brightness threshold value of each color channel on the slave device, the maximum brightness threshold value of each color channel on the master device and the gray-scale value of each color channel of each pixel on the master device.

After the maximum brightness threshold values of the color channels on the slave device are adjusted to make the ratio of the target brightness threshold values of the color channels on the slave device the same as the ratio of the maximum brightness threshold values of the color channels on the master device or the difference between the target brightness threshold values and the maximum brightness threshold values of the color channels on the master device within a preset range, the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave device is adjusted. Specifically, the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave device is adjusted according to the target brightness threshold value of each color channel on the slave device, the maximum brightness threshold value of each color channel on the master device, and the gray-scale value of each color channel of each pixel on the master device.

When the gray-scale value of each color channel of each pixel is adjusted when the picture to be projected is displayed on the slave device, the adjustment can be carried out according to the Gamma curve. The Gamma curve is used as a relation graph of an input signal (gray-scale value) and output brightness, and plays an important role in the display effect of the display device.

And step 280, displaying on the slave equipment to generate a screen projection picture based on the adjusted gray-scale value of each color channel of each pixel.

After the gray-scale value of each color channel of each pixel is adjusted when the screen to be projected is displayed on the slave device, the screen to be projected can be generated by displaying on the slave device based on the adjusted gray-scale value of each color channel of each pixel.

In practice, the slave device receives a display signal corresponding to a to-be-projected picture sent by the master device, and the display signal includes RGB gray scale values of each pixel point on the to-be-projected picture. As shown in fig. 3, the slave device processes the received display signal through the codec module 320, the display engine 340, and the display driver IC 360, respectively, and displays the result on the display screen 380. Surface flickers, DRM, and plug-in ICs are also included for some display engines 340. The display method of the picture to be projected in the embodiment of the application can be used for color adjustment in the encoding and decoding module, the display engine and the drive IC, so that the high color reduction degree and the consistent or close display effect of the display pictures on the master device and the slave device are realized.

In the embodiment of the application, the maximum brightness threshold of each color channel on the slave device is adjusted, so that the target brightness threshold of each color channel on the slave device is obtained. And then adjusting the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave equipment based on the target brightness threshold value of each color channel on the slave equipment, the maximum brightness threshold value of each color channel on the master equipment and the gray-scale value of each color channel of each pixel on the master equipment. Therefore, the color temperature of the screen projection picture displayed on the slave equipment is approximate to that of the screen to be projected on the master equipment, and the color restoration degree of the screen to be projected is improved.

In an embodiment, the adjusting the maximum luminance threshold of each color channel on the slave device according to the maximum luminance threshold of each color channel on the master device and the maximum luminance threshold of each color channel on the slave device to obtain the target luminance threshold of each color channel on the slave device includes:

and according to the maximum brightness threshold of each color channel on the master device and the maximum brightness threshold of each color channel on the slave device, keeping the maximum brightness threshold of one color channel on the slave device unchanged, and adjusting the maximum brightness thresholds of other color channels on the slave device to obtain the target brightness threshold of each color channel on the slave device.

For example, if the red color of the master device is darker and the red color of the slave device is lighter, the same display signal is transmitted to the master device and the display of the slave device with respect to the master device is entirely redder. Therefore, in order to make the display color temperatures of the master device and the slave device consistent, the maximum brightness threshold of the green channel is kept unchanged, and the maximum brightness thresholds of the red channel and the blue channel are reduced to obtain the target brightness threshold of each color channel on the slave device. The display color temperature of the adjusted slave equipment is approximate to that of the master equipment, so that the color reduction degree of the picture to be projected is improved.

In this embodiment of the present application, when the maximum luminance threshold of each color channel on the slave device is adjusted, the maximum luminance threshold of one color channel is kept unchanged, and the maximum luminance thresholds of other color channels except for the color channel are reduced, so as to obtain the target luminance threshold of each color channel on the slave device. And enabling the display color temperature of the adjusted slave equipment to be consistent with the display color temperature of the master equipment.

In one embodiment, as shown in fig. 4, step 240, adjusting the maximum luminance threshold of each color channel on the slave device according to the maximum luminance threshold of each color channel on the master device and the maximum luminance threshold of each color channel on the slave device, to obtain the target luminance threshold of each color channel on the slave device, includes:

step 242, determining a first brightness threshold ratio of the main device according to the maximum brightness threshold of each color channel on the main device; the first brightness threshold ratio is a ratio of a red channel maximum brightness threshold on the main device, a green channel maximum brightness threshold on the main device and a blue channel maximum brightness threshold on the main device.

When the maximum brightness threshold of each color channel on the slave device is adjusted according to the maximum brightness threshold of each color channel on the master device and the maximum brightness threshold of each color channel on the slave device to obtain the target brightness threshold of each color channel on the slave device, in the first step, the first brightness threshold ratio of the master device is determined according to the maximum brightness threshold of each color channel on the master device. Wherein the maximum brightness threshold for each color channel on the master device is typically a fixed value. For an 8-bit display, when the gray scale value of the RGB three color channels is 255, the luminance corresponding to the RGB three color channels at this time is the maximum luminance threshold of the RGB three color channels on the display. A red channel maximum luminance threshold (e.g., 100nit) on the master, a green channel maximum luminance threshold (e.g., 200nit) on the master, and a blue channel maximum luminance threshold (e.g., 300nit) on the master may then be obtained. And finally, calculating the ratio of the maximum brightness threshold of the red channel on the main device to the maximum brightness threshold of the green channel on the main device to the maximum brightness threshold of the blue channel on the main device to be 100 nit: 200 nit: 300nit, a first luminance threshold ratio of 100nit is obtained: 200 nit: 300 nit.

Where nit is the unit of luminance, 1nit 1cd/m 2. The brightness is a physical quantity of the intensity of light emission (reflection) on the surface of a light-emitting body (reflector).

Step 244, determining a second brightness threshold ratio of the slave device according to the maximum brightness threshold of each color channel on the slave device; wherein the second brightness threshold ratio is a ratio of a red channel maximum brightness threshold on the slave device, a green channel maximum brightness threshold on the slave device, and a blue channel maximum brightness threshold on the slave device.

And secondly, determining a first brightness threshold ratio of the slave device according to the maximum brightness threshold of each color channel on the slave device. Similarly, the maximum luminance threshold for each color channel on the slave device is typically a fixed value. For an 8-bit display, when the gray scale value of the RGB three color channels is 255, the luminance corresponding to the RGB three color channels at this time is the maximum luminance threshold of the RGB three color channels on the display. A red channel maximum luminance threshold (e.g., 100nit) on the slave device, a green channel maximum luminance threshold (e.g., 150nit) on the slave device, and a blue channel maximum luminance threshold (e.g., 400nit) on the slave device may then be obtained. Finally, the ratio 100nit between the red channel maximum luminance threshold on the slave device, the green channel maximum luminance threshold on the slave device and the blue channel maximum luminance threshold on the slave device is calculated: 150nit: 400nit, a second luminance threshold ratio of 100nit is obtained: 150nit: 400 nit.

Step 246, adjusting the maximum brightness threshold of each color channel on the slave device according to the first brightness threshold ratio and the second brightness threshold ratio to obtain a target brightness threshold of each color channel on the slave device; wherein the ratio between the target luminance threshold values of the respective color channels on the slave device is equal to the first luminance threshold ratio.

Since the maximum brightness threshold of each color channel on the slave device is the maximum brightness of the slave device, when the maximum brightness threshold of each color channel on the slave device is adjusted according to the first brightness threshold ratio and the second brightness threshold ratio, the maximum brightness of the slave device can only be reduced or unchanged, and the maximum brightness of the slave device cannot be increased. And the target brightness threshold after adjustment of each color channel on the slave device needs to satisfy that the ratio between the target brightness thresholds of each color channel on the slave device is equal to the first brightness threshold ratio, that is, equal to the ratio between the maximum brightness thresholds of the three RGB color channels on the master device.

For the example above, the red channel maximum luminance threshold on the master (e.g., 100nit), the green channel maximum luminance threshold on the master (e.g., 200nit), and the blue channel maximum luminance threshold on the master (e.g., 300 nit). And finally, calculating the ratio 100nit of the maximum brightness threshold of the red channel on the main device, the maximum brightness threshold of the green channel on the main device and the maximum brightness threshold of the blue channel on the main device: 200 nit: 300nit, a first luminance threshold ratio of 100nit is obtained: 200 nit: 300 nit.

A red channel maximum luminance threshold on the slave device (e.g., 100nit), a green channel maximum luminance threshold on the slave device (e.g., 150nit), and a blue channel maximum luminance threshold on the slave device (e.g., 400 nit). Finally, the ratio 100nit between the red channel maximum luminance threshold on the slave device, the green channel maximum luminance threshold on the slave device and the blue channel maximum luminance threshold on the slave device is calculated: 150nit: 400nit, a second luminance threshold ratio of 100nit is obtained: 150nit: 400 nit.

Then, when the maximum brightness of the slave device is adjusted, the maximum brightness of the slave device may be reduced or unchanged, and the target brightness threshold after the adjustment of each color channel on the slave device needs to satisfy that the ratio between the target brightness thresholds of each color channel on the slave device is equal to the first brightness threshold ratio. Therefore, it is necessary to keep the maximum luminance threshold (e.g., 150nit) of the green channel on the slave device constant, and reduce the maximum luminance threshold of the red and blue channels on the slave device. Specifically, the maximum luminance threshold of the red channel on the slave device is reduced to (75nit), and the maximum luminance threshold of the blue channel on the slave device is reduced to (225 nit). Thus, the ratio between the target luminance threshold values for the respective color channels on the slave device is equal to the first luminance threshold ratio 75nit:150nit:225 nit. Of course, the maximum luminance of the slave device may also be adjusted such that the ratio between the target luminance thresholds of the respective color channels on the slave device is approximately equal to the first luminance threshold ratio 100 nit: 200 nit: 300 nit. This is not limited in this application.

In the embodiment of the application, when the ratio of the maximum brightness threshold values of the respective color channels on the different devices is the same or the difference between the maximum brightness threshold values is within the preset range, the color reduction degree between the display frames on the two different devices is higher, and the display effects are consistent or close. Therefore, the target brightness threshold after adjustment of each color channel on the slave device is obtained by reducing or keeping the maximum brightness of the slave device. And the ratio of the target brightness threshold values of all the color channels on the slave equipment is equal to the first brightness threshold value ratio, namely equal to the ratio of the maximum brightness threshold values of the three RGB color channels on the master equipment, so that the color trends of the master equipment and the slave equipment are approximate or consistent when the master equipment and the slave equipment are displayed. Therefore, the high color reduction degree and the consistent or close display effect between the display pictures on two different devices can be realized.

In one embodiment, as shown in fig. 5, adjusting the maximum luminance threshold of each color channel on the slave device according to the first luminance threshold ratio and the second luminance threshold ratio to obtain the target luminance threshold of each color channel on the slave device includes:

and 520, respectively carrying out normalization processing on the first brightness threshold ratio and the second brightness threshold ratio, and determining a reference brightness threshold from the maximum brightness threshold of each color channel on the slave device according to the result after the normalization processing.

The normalization process has two forms, one is to change data into a decimal number between (0, 1), and the other is to change a dimensional expression into a dimensionless expression. The normalization process in the embodiment of the present application is a first form, and the normalization process is performed on the first luminance threshold ratio 100 nit: 200 nit: 300nit and second luminance threshold ratio 100 nit:150nit: 400nit is normalized and divided by the maximum luminance threshold 100nit for the red channel on the master. Thus, the result of normalization processing on the first brightness threshold ratio is 1:2:3, the result of normalization processing on the second brightness threshold ratio is 1:1.5:4, and size comparison can be conveniently and rapidly carried out after normalization processing.

Then, based on the size comparison result, a reference luminance threshold value is determined from the maximum luminance threshold values of the respective color channels on the slave device. The principle of determining the reference brightness threshold value is as follows: when the maximum brightness threshold of each color channel on the slave device is adjusted, the reference brightness threshold is kept unchanged, and the maximum brightness thresholds of other color channels except the color channel corresponding to the reference brightness threshold are reduced, so that the target brightness threshold of each color channel on the slave device can be obtained. Such that the ratio between the target luminance threshold values for the respective color channels on the slave device is equal to the first luminance threshold ratio.

For example, based on the result of normalizing the first luminance threshold ratio by 1:2:3 and the result of normalizing the second luminance threshold ratio by 1:1.5:4, the target luminance threshold values of the respective color channels on the slave device can be obtained by lowering the maximum luminance threshold values of the red and blue channels except for the green channel, with the maximum luminance threshold value of the green channel on the slave device as the reference luminance threshold value, so that the ratio of the target luminance threshold values is equal to the first luminance threshold ratio.

And 540, when the maximum brightness threshold of each color channel on the slave device is adjusted, keeping the reference brightness threshold unchanged, and reducing the maximum brightness thresholds of the other color channels except the color channel corresponding to the reference brightness threshold to obtain the target brightness threshold of each color channel on the slave device.

Therefore, when the maximum brightness threshold of each color channel on the slave device is adjusted, the maximum brightness threshold of the green channel on the slave device is kept unchanged, and the maximum brightness thresholds of the red and blue channels except the green channel are reduced, so that the target brightness threshold of each color channel on the slave device can be obtained, and the ratio of the target brightness threshold to the target brightness threshold is equal to the first brightness threshold ratio. For example, the maximum luminance threshold for the red channel is reduced to 75nit and the maximum luminance threshold for the blue channel is reduced to 225 nit.

In the embodiment of the application, the first brightness threshold ratio and the second brightness threshold ratio are respectively subjected to normalization processing, and data are mapped into the range of 0-1, so that the size comparison can be conveniently and rapidly carried out. And determining a reference luminance threshold value from the maximum luminance threshold values of the respective color channels on the slave device based on the size comparison result. When the maximum brightness threshold of each color channel on the slave device is adjusted, the maximum brightness threshold of the green channel on the slave device is kept unchanged, and the maximum brightness thresholds of the red and blue channels except the green channel are reduced, so that the target brightness threshold of each color channel on the slave device can be obtained, the ratio of the target brightness thresholds is equal to the ratio of the first brightness thresholds, and the color trends of the master device and the slave device are approximate or consistent when the master device and the slave device display are ensured. Therefore, the high color reduction degree and the consistent or close display effect between the display pictures on two different devices can be realized.

In one embodiment, if the result of the normalization process of the first luminance threshold ratio is L: M: N, the result of the normalization process of the second luminance threshold ratio is P: Q: R, where L ═ P ═ 1, M is the ratio between the maximum luminance threshold of the green channel on the master device and the maximum luminance threshold of the red channel on the master device, N is the ratio between the maximum luminance threshold of the blue channel on the master device and the maximum luminance threshold of the red channel on the master device, Q is the ratio between the maximum luminance threshold of the green channel on the slave device and the maximum luminance threshold of the red channel on the slave device, and R is the ratio between the maximum luminance threshold of the blue channel on the slave device and the maximum luminance threshold of the red channel on the slave device;

according to the result after the normalization processing, determining a reference brightness threshold value from the maximum brightness threshold values of all color channels on the slave device, including:

the reference luminance threshold is determined from the maximum luminance thresholds of the respective color channels on the slave device based on the magnitude relationship between M, N, Q and R.

As shown in table 1, the maximum luminance threshold value for each color channel of the master device (display apparatus a) and the slave device (display apparatus B):

TABLE 1

	Display device A	Display device B
			R maximum luminance threshold	RA	RB
G maximum luminance threshold	GA	GB
			B maximum luminance threshold	BA	BB

Specifically, the first luminance threshold ratio RA: GA: BA is normalized and divided by the maximum brightness threshold RA of the red channel on the master device. For the second luminance threshold ratio RB: GB: BB performs normalization processes, both divided by the maximum luminance threshold RB of the red channel on the slave device. Thus, the result L of normalization processing on the first brightness threshold ratio is obtained, wherein M: N is 1: GA/RA: BA/RA, and the result P: Q: R is 1: GB/RB: BB/RB of normalization processing on the second brightness threshold ratio, and the size comparison can be conveniently and quickly carried out after the normalization processing.

For example, the red channel maximum luminance threshold on the master, the green channel maximum luminance threshold on the master, and the blue channel maximum luminance threshold on the master are 100nit, 200nit, 300nit, respectively. The red channel maximum luminance threshold on the slave device, the green channel maximum luminance threshold on the slave device, and the blue channel maximum luminance threshold on the slave device are 100nit, 150nit, 400nit, respectively. For the first luminance threshold ratio 100 nit: 200 nit: 300nit and second luminance threshold ratio 100 nit:150nit: normalization was performed at 400nit, and all were divided by 100 nit. This results in the result of the normalization process on the first luminance threshold ratio L: M: N being 1:2:3 and the result of the normalization process on the second luminance threshold ratio P: Q: R being 1:1.5:4, which facilitates a quick size comparison after the normalization process.

Then, based on the magnitude comparison between M, N, Q and R, a reference luminance threshold is determined from the maximum luminance thresholds for the respective color channels on the device. The principle of determining the reference brightness threshold value is as follows: when the maximum brightness threshold of each color channel on the slave device is adjusted, the reference brightness threshold is kept unchanged, and the maximum brightness thresholds of other color channels except the color channel corresponding to the reference brightness threshold are reduced, so that the target brightness threshold of each color channel on the slave device can be obtained. Such that the ratio between the target luminance threshold values for the respective color channels on the slave device is equal to the first luminance threshold ratio.

In the embodiment of the present application, the reference luminance threshold value is determined from the maximum luminance threshold values of the respective color channels on the slave device based on the magnitude comparison result between M, N, Q and R. When the maximum brightness threshold of each color channel on the slave equipment is adjusted, the reference brightness threshold is kept unchanged, and the maximum brightness thresholds of other color channels except the color channel corresponding to the reference brightness threshold are reduced, so that the target brightness threshold of each color channel on the slave equipment can be obtained, the ratio of the target brightness thresholds is equal to the ratio of the first brightness thresholds, and the color trends of the master equipment and the slave equipment are approximate or consistent when the master equipment and the slave equipment are displayed. Therefore, the high color reduction degree and the consistent or close display effect between the display pictures on two different devices can be realized.

In one embodiment, determining the reference luminance threshold from the maximum luminance thresholds of the respective color channels on the device according to the magnitude relationship between M, N, Q and R includes:

if M is larger than or equal to Q and N is smaller than or equal to R, determining the maximum brightness threshold of the green channel as a reference brightness threshold from the maximum brightness thresholds of all the color channels on the slave equipment;

and if M is larger than or equal to Q and N is larger than or equal to R, determining the maximum brightness threshold of the green channel or the blue channel as a reference brightness threshold from the maximum brightness thresholds of all the color channels on the equipment.

Specifically, after the result L: M: N of normalization processing of the first luminance threshold ratio and the result P: Q: R of normalization processing of the second luminance threshold ratio are obtained, the reference luminance threshold is determined from the maximum luminance thresholds of the respective color channels on the slave device according to the magnitude relationship between M, N, Q and R. And if M is more than or equal to Q and N is less than or equal to R, determining the maximum brightness threshold of the green channel as the reference brightness threshold from the maximum brightness thresholds of all the color channels on the slave equipment. And if M is larger than or equal to Q and N is larger than or equal to R, determining the maximum brightness threshold of the green channel or the blue channel as a reference brightness threshold from the maximum brightness thresholds of all the color channels on the equipment.

For example, for a first luminance threshold ratio of 100 nit: 200 nit: 300nit and second luminance threshold ratio 100 nit:150nit: normalization was performed at 400nit, and all were divided by 100 nit. This results in the result of the normalization process on the first luminance threshold ratio L: M: N being 1:2:3 and the result of the normalization process on the second luminance threshold ratio P: Q: R being 1:1.5: 4. And comparing M, N, Q with R to obtain M is more than or equal to Q and N is less than or equal to R, so that the maximum brightness threshold of the green channel is determined from the maximum brightness thresholds of all color channels on the equipment as the reference brightness threshold. In this way, when the maximum brightness threshold of each color channel on the slave device is adjusted, the maximum brightness threshold (150nit) of the green color channel on the slave device is kept unchanged, and the maximum brightness thresholds of the red and blue color channels except the green color channel are reduced to (75nit) and (225nit), so that the target brightness threshold of each color channel on the slave device can be obtained, and the ratio of the target brightness thresholds is equal to or approximately equal to the first brightness threshold ratio.

For example, for a first luminance threshold ratio of 100 nit: 200 nit: 300nit and second luminance threshold ratio 100 nit:150nit: normalization was performed at 250nit, and all were divided by 100 nit. This results in the result of the normalization process on the first luminance threshold ratio L: M: N being 1:2:3 and the result of the normalization process on the second luminance threshold ratio P: Q: R being 1:1.5: 2.5. And comparing M, N, Q and R to obtain M is more than or equal to Q and N is more than or equal to R, so that the maximum brightness threshold of the green channel or the blue channel is determined as the reference brightness threshold from the maximum brightness thresholds of the color channels on the equipment. In this way, when the maximum brightness threshold of each color channel on the slave device is adjusted, the maximum brightness threshold (150nit) of the green color channel on the slave device is kept unchanged, and the maximum brightness thresholds of the red and blue color channels except the green color channel are reduced to (75nit) and (225nit), so that the target brightness threshold of each color channel on the slave device can be obtained, and the ratio of the target brightness thresholds is equal to or approximately equal to the first brightness threshold ratio.

For example, for a first luminance threshold ratio of 100 nit: 200 nit: 300nit and second luminance threshold ratio 100 nit: 200 nit: the normalization process was performed at 250nit, and both were divided by 100 nit. This results in the result of the normalization process on the first luminance threshold ratio L: M: N being 1:2:3 and the result of the normalization process on the second luminance threshold ratio P: Q: R being 1:2: 2.5. And comparing M, N, Q and R to obtain M ≧ Q and N ≧ R, so the maximum brightness threshold of the blue channel is determined from the maximum brightness thresholds of each color channel on the device as the reference brightness threshold. Thus, when the maximum brightness threshold of each color channel on the slave device is adjusted, the maximum brightness threshold (250nit) of the blue color channel on the slave device is kept unchanged, and the maximum brightness thresholds of the red and green color channels except the blue color channel are reduced to (83.3nit) and (166.6nit), so that the target brightness threshold of each color channel on the slave device can be obtained, and the ratio of the target brightness threshold to the first brightness threshold ratio is equal to or approximately equal to the first brightness threshold ratio.

In the embodiment of the present application, determining the reference luminance threshold from the maximum luminance thresholds of the respective color channels on the device according to the magnitude relationship between M, N, Q and R includes: for the condition that M is larger than or equal to Q and N is smaller than or equal to R, determining the maximum brightness threshold of the green channel as a reference brightness threshold from the maximum brightness thresholds of all color channels on the slave equipment; and for the condition that M is larger than or equal to Q and N is larger than or equal to R, determining the maximum brightness threshold of the green channel or the blue channel as a reference brightness threshold from the maximum brightness thresholds of all the color channels on the equipment. Therefore, by keeping the reference luminance threshold constant and decreasing the maximum luminance threshold of the color channels other than the color channel corresponding to the reference luminance threshold, the maximum luminance threshold of any one color channel cannot be increased. And at the same time, the ratio of the target brightness threshold values of the various color channels on the slave device can be made equal to the first brightness threshold ratio.

In the above embodiment, determining the reference luminance threshold from the maximum luminance thresholds of the respective color channels on the device according to the magnitude relationship between M, N, Q and R includes:

if M is less than or equal to Q and N is less than or equal to R, determining the maximum brightness threshold of the red channel as a reference brightness threshold from the maximum brightness thresholds of all the color channels on the slave equipment;

and if M is less than or equal to Q and N is more than or equal to R, determining the maximum brightness threshold of the blue channel as the reference brightness threshold from the maximum brightness thresholds of all the color channels on the slave equipment.

Specifically, similarly, when the maximum luminance threshold of each color channel on the slave device is adjusted, the reference luminance threshold is kept unchanged, and the maximum luminance thresholds of the other color channels except the color channel corresponding to the reference luminance threshold are reduced, so that the target luminance threshold of each color channel on the slave device can be obtained, and the ratio of the target luminance threshold to the maximum luminance threshold of each color channel on the slave device is equal to the first luminance threshold ratio.

Therefore, if M is less than or equal to Q and N is less than or equal to R, determining the maximum brightness threshold of the red channel as the reference brightness threshold from the maximum brightness thresholds of all the color channels on the equipment; and if M is less than or equal to Q and N is more than or equal to R, determining the maximum brightness threshold of the blue channel as the reference brightness threshold from the maximum brightness thresholds of all the color channels on the slave equipment. The target luminance threshold values for the various color channels on the slave device are obtained with a ratio equal to the first luminance threshold ratio. And are not illustrated here.

In the embodiment of the present application, determining the reference luminance threshold from the maximum luminance thresholds of the respective color channels on the device according to the magnitude relationship between M, N, Q and R includes: for the condition that M is less than or equal to Q and N is less than or equal to R, determining the maximum brightness threshold of the red channel as a reference brightness threshold from the maximum brightness thresholds of all the color channels on the equipment; and determining the maximum brightness threshold of the blue channel as the reference brightness threshold from the maximum brightness thresholds of all the color channels on the equipment under the condition that M is less than or equal to Q and N is greater than or equal to R. Therefore, by keeping the reference luminance threshold constant and decreasing the maximum luminance threshold of the color channels other than the color channel corresponding to the reference luminance threshold, the maximum luminance threshold of any one color channel cannot be increased. And at the same time, the ratio of the target brightness threshold values of the various color channels on the slave device can be made equal to the first brightness threshold ratio.

In one embodiment, if M ≧ Q and N ≧ R, determining the maximum luminance threshold for the green channel or the blue channel from the maximum luminance thresholds for the respective color channels on the device as the reference luminance threshold includes:

if M is more than or equal to Q and N is more than or equal to R, judging the size relationship between M, N and Q, R;

if M is not less than Q and R is not less than Q, determining the maximum brightness threshold of the blue channel from the maximum brightness thresholds of all color channels on the slave equipment as a reference brightness threshold;

and if M, N is less than or equal to Q, R, determining the maximum brightness threshold of the green channel from the maximum brightness thresholds of the color channels on the slave equipment as a reference brightness threshold.

Specifically, for the case that M is larger than or equal to Q and N is larger than or equal to R, the maximum brightness threshold of the green channel or the blue channel is determined as the reference brightness threshold from the maximum brightness thresholds of the color channels on the equipment. Wherein, after M is more than or equal to Q and N is more than or equal to R, the size relationship between M, N and Q, R is further judged. If M: N is larger than or equal to Q: R, the maximum brightness threshold of any color channel can not be increased only by keeping the maximum brightness threshold of the blue channel unchanged and reducing the maximum brightness thresholds of the red and green channels. And at the same time, the ratio of the target brightness threshold values of the various color channels on the slave device can be made equal to the first brightness threshold ratio.

If M, N and Q, R are judged to be less than or equal to M, then the maximum brightness threshold of any color channel can not be increased only by keeping the maximum brightness threshold of the green channel unchanged and reducing the maximum brightness thresholds of the red and blue channels. And at the same time, the ratio of the target brightness threshold values of the various color channels on the slave device can be made equal to the first brightness threshold ratio.

In the embodiment of the application, the conditions that M is more than or equal to Q and N is more than or equal to R are further subdivided into two conditions: m, N is more than or equal to Q, R and M, N is less than or equal to Q, R, and the specific maximum brightness threshold of the color channel of the reference brightness threshold in each case is clear. Furthermore, it is convenient to uniquely determine the specific maximum luminance threshold of the color channel as the reference luminance threshold after accurately determining the magnitude relationship between M, N, Q and R and the magnitude relationship between M: N and Q: R in practice. Accurate determination of target brightness thresholds for respective color channels on the slave device is facilitated.

In one embodiment, as shown in fig. 6, the step 260 of adjusting the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave device according to the target brightness threshold of each color channel on the slave device, the maximum brightness threshold of each color channel on the master device, and the gray-scale value of each color channel of each pixel on the master device includes:

step 262, calculating the brightness ratio of each color channel between the slave device and the master device according to the target brightness threshold of each color channel on the slave device and the maximum brightness threshold of each color channel on the master device.

After the target brightness threshold value of each color channel on the slave device and the maximum brightness threshold value of each color channel on the master device are obtained, the brightness of each color channel between the slave device and the master device is compared, and then the ratio of the brightness of each color channel between the slave device and the master device is obtained.

For example, we get a target luminance threshold of 75nit from the RGB color channels on the device: 150nit:225nit, the maximum luminance threshold of each color channel on the master is 100 nit: 200 nit: 300 nit. Comparing the luminance of each color channel between the slave and the master, we get the ratio 75nit of the luminance of the red channel between the slave and the master: 100 nit-3: 4, resulting in a ratio of luminance of the green channel between the slave and master of 150nit: 200nit is 3:4, resulting in a ratio 225nit of the luminance of the blue channel between the slave and master: 300nit ═ 3: 4. I.e. a ratio of 3:4 for the luminance of each color channel between the slave device and the master device is obtained.

And step 264, calculating the brightness of each color channel of each pixel on the main device according to the gray-scale value of each color channel of each pixel on the main device and the Gamma curve of each color channel of the main device.

The Gamma curve is a relationship between a gray level value and an output luminance, and as shown in fig. 7A, is a schematic diagram of a Gamma curve of a certain color channel of a display device a. Fig. 7B is a schematic diagram of Gamma curves of a certain color channel of two display devices a and B, and the Gamma value of the display device B is greater than that of the display device a. The Gamma values of the Gamma curves of the color channels of each display device may be different from each other or the same, which is not limited in the present application.

If the gray-scale value of each color channel of each pixel on the main device and the Gamma curve of each color channel of the main device are known, the brightness of each color channel of each pixel on the main device can be directly obtained.

Specifically, the calculation can be performed by the following formula:

wherein, y_ARefers to the brightness, Y, of each color channel of each pixel point on the host device_A0Refers to the minimum luminance threshold, Y, of each color channel on the host device_A255Refers to the maximum luminance threshold, x, of each color channel on the host device_AThe gray scale value of each color channel of each pixel point on the main device is referred to, and the mA is the Gamma value of the Gamma curve of each color channel of each pixel point on the main device.

And 266, calculating the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave device according to the brightness of each color channel of each pixel on the master device, the brightness ratio of the corresponding color channel between the slave device and the master device and the Gamma curve of the corresponding color channel of the slave device.

Specifically, the luminance of the corresponding color channel of each pixel on the slave device is calculated according to the ratio of the luminance of each color channel of each pixel on the master device to the luminance of the corresponding color channel between the slave device and the master device. In this way, it is ensured that the ratio of the luminance of the individual color channels of each pixel on the slave device is similar or identical to the ratio of the luminance of the individual color channels on the master device. Thus, the color tendencies of the master device and the slave device when displaying are ensured to be approximate or consistent.

If the brightness of each color channel of each pixel on the slave device and the Gamma curve of each color channel of the slave device are known, the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave device can be directly calculated.

In the embodiment of the application, the Gamma curves of the color channels of the master device and the Gamma curves of the color channels corresponding to the slave device are combined, and the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave device is calculated according to the gray-scale value of each color channel of each pixel on the master device. In this way, it is ensured that the ratio of the luminance of the individual color channels of each pixel on the slave device is similar or identical to the ratio of the luminance of the individual color channels on the master device. Thus, the color tendencies of the master device and the slave device when displaying are ensured to be approximate or consistent. Furthermore, the color temperature of the screen projection picture displayed on the slave equipment is approximate to that of the screen to be projected on the master equipment, so that the color restoration degree of the screen to be projected is improved.

In another embodiment, calculating the gray-scale value of each color channel of each pixel when the to-be-projected picture is displayed on the slave device according to the luminance of each color channel of each pixel on the master device, the luminance ratio of the corresponding color channel between the slave device and the master device, and the Gamma curve of the corresponding color channel of the slave device includes:

calculating the brightness of the corresponding color channel of each pixel on the slave device according to the ratio of the brightness of each color channel of each pixel on the master device to the brightness of the corresponding color channel between the slave device and the master device;

specifically, in the above embodiment, the ratio of the luminance of the corresponding color channel between the slave device and the master device is calculated, and then the luminance of each color channel of each pixel on the master device is multiplied by the ratio of the luminance, so as to obtain the luminance of the corresponding color channel of each pixel on the slave device. For example, it is obtained that the ratio of the luminance of each color channel between the slave device and the master device is 3: 4. Then y is_B＝y_AX 3:4, the brightness y of each color channel of each pixel point on the main equipment is calculated_B。

And calculating each color channel gray-scale value of each pixel when the picture to be projected is displayed on the slave equipment according to the brightness of the corresponding color channel of each pixel on the slave equipment and the Gamma curve of the corresponding color channel of the slave equipment.

Specifically, the calculation can be performed by the following formula:

wherein, y_BRefers to the brightness, Y, of each color channel of each pixel point on the host device_B0Refers to the minimum luminance threshold, Y, of each color channel on the host device_B255Refers to the maximum luminance threshold, x, of each color channel on the host device_BThe gray scale value of each color channel of each pixel point on the main device is referred to, and the mB refers to the Gamma value of the Gamma curve of each color channel of each pixel point on the main device.

In the embodiment of the present application, after the brightness of each color channel of each pixel on the host device is calculated through the Gamma curve of each color channel of each pixel on the host device. And obtaining the brightness of each color channel of each pixel on the slave device based on the product of the brightness of each color channel of each pixel on the master device and the brightness of the corresponding color channel between the slave device and the master device. And then, based on the Gamma curve of the color channel corresponding to the slave equipment, the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave equipment can be calculated. In this way, it is ensured that the ratio of the luminance of the individual color channels of each pixel on the slave device is similar or identical to the ratio of the luminance of the individual color channels on the master device.

In a specific embodiment, a method for displaying a to-be-projected picture is provided, which includes:

step one, responding to a screen projection instruction, and receiving a screen to be projected sent by main equipment;

determining a first brightness threshold ratio of the master device according to the maximum brightness threshold of each color channel on the master device under the condition of determining that the display color temperatures of the master device and the slave device are inconsistent;

step three, determining a second brightness threshold ratio of the slave device according to the maximum brightness threshold of each color channel on the slave device;

respectively carrying out normalization processing on the first brightness threshold ratio and the second brightness threshold ratio, wherein if the result of the normalization processing of the first brightness threshold ratio is L: M: N, the result of the normalization processing of the second brightness threshold ratio is P: Q: R; determining a reference brightness threshold value from the maximum brightness threshold values of all color channels on the equipment according to the size relation between M, N, Q and R and the size relation between M: N and Q: R;

step five, when the maximum brightness threshold of each color channel on the slave equipment is adjusted, keeping the reference brightness threshold unchanged, and reducing the maximum brightness thresholds of other color channels except the color channel corresponding to the reference brightness threshold to obtain the target brightness threshold of each color channel on the slave equipment;

step six, calculating the brightness ratio of each color channel between the slave equipment and the master equipment according to the target brightness threshold value of each color channel on the slave equipment and the maximum brightness threshold value of each color channel on the master equipment;

step seven, calculating the brightness of each color channel of each pixel on the main equipment according to the gray-scale value of each color channel of each pixel on the main equipment and the Gamma curve of each color channel of the main equipment;

step eight, calculating the brightness of the corresponding color channel of each pixel on the slave device according to the ratio of the brightness of each color channel of each pixel on the master device to the brightness of the corresponding color channel between the slave device and the master device;

and step nine, calculating each color channel gray-scale value of each pixel when the picture to be projected is displayed on the slave equipment according to the brightness of the corresponding color channel of each pixel on the slave equipment and the Gamma curve of the corresponding color channel of the slave equipment.

In one embodiment, as shown in fig. 8, there is provided a display apparatus 800 for a screen to be projected, including:

a screen to be projected receiving module 820, configured to receive, in response to a screen projection instruction, a screen to be projected sent by a host device;

a brightness threshold adjusting module 840, configured to, when it is determined that the display color temperatures of the master device and the slave device are not consistent, adjust the maximum brightness threshold of each color channel on the slave device according to the maximum brightness threshold of each color channel on the master device and the maximum brightness threshold of each color channel on the slave device, to obtain a target brightness threshold of each color channel on the slave device;

a gray scale value adjusting module 860, configured to adjust each color channel gray scale value of each pixel when the to-be-projected-screen picture is displayed on the slave device according to the target brightness threshold of each color channel on the slave device, the maximum brightness threshold of each color channel on the master device, and each color channel gray scale value of each pixel on the master device;

and a display module 880, configured to display on the slave device to generate a screen projection screen based on the adjusted color channel gray-scale value of each pixel.

In one embodiment, as shown in fig. 9, the brightness threshold adjusting module 840 includes:

a first brightness threshold ratio determining unit 842, configured to determine a first brightness threshold ratio of the host device according to a maximum brightness threshold of each color channel on the host device; the first brightness threshold ratio is the ratio of the maximum brightness threshold of the red channel on the main device, the maximum brightness threshold of the green channel on the main device and the maximum brightness threshold of the blue channel on the main device;

a second luminance threshold ratio determining unit 844, configured to determine a second luminance threshold ratio of the slave device according to the maximum luminance threshold of each color channel on the slave device; the second brightness threshold ratio is the ratio of the maximum brightness threshold of the red channel on the slave device, the maximum brightness threshold of the green channel on the slave device and the maximum brightness threshold of the blue channel on the slave device;

a target brightness threshold calculation unit 846, configured to adjust a maximum brightness threshold of each color channel on the slave device according to the first brightness threshold ratio and the second brightness threshold ratio, to obtain a target brightness threshold of each color channel on the slave device; wherein the ratio between the target luminance threshold values of the respective color channels on the slave device is equal to the first luminance threshold ratio.

In one embodiment, the target luminance threshold calculation unit 846 is further configured to perform normalization processing on the first luminance threshold ratio and the second luminance threshold ratio, respectively, and determine a reference luminance threshold from the maximum luminance thresholds of the respective color channels on the slave device according to a result after the normalization processing; when the maximum brightness threshold value of each color channel on the slave device is adjusted, the reference brightness threshold value is kept unchanged, and the maximum brightness threshold values of other color channels except the color channel corresponding to the reference brightness threshold value are reduced to obtain the target brightness threshold value of each color channel on the slave device.

In one embodiment, if the result of the normalization process of the first luminance threshold ratio is L: M: N, the result of the normalization process of the second luminance threshold ratio is P: Q: R, where L ═ P ═ 1, M is the ratio between the maximum luminance threshold of the green channel on the master device and the maximum luminance threshold of the red channel on the master device, N is the ratio between the maximum luminance threshold of the blue channel on the master device and the maximum luminance threshold of the red channel on the master device, Q is the ratio between the maximum luminance threshold of the green channel on the slave device and the maximum luminance threshold of the red channel on the slave device, and R is the ratio between the maximum luminance threshold of the blue channel on the slave device and the maximum luminance threshold of the red channel on the slave device; and the target brightness threshold calculation unit 846 is further used for determining the reference brightness threshold from the maximum brightness thresholds of the respective color channels on the device according to the magnitude relation between M, N, Q and R.

In one embodiment, the target brightness threshold calculation unit 846 is further configured to determine the maximum brightness threshold of the green channel as the reference brightness threshold from the maximum brightness thresholds of the respective color channels on the device if M is greater than or equal to Q and N is less than or equal to R; and if M is larger than or equal to Q and N is larger than or equal to R, determining the maximum brightness threshold of the green channel or the blue channel as a reference brightness threshold from the maximum brightness thresholds of all the color channels on the equipment.

In one embodiment, the target luminance threshold calculation unit 846 is further configured to determine the maximum luminance threshold of the red channel as the reference luminance threshold from the maximum luminance thresholds of the respective color channels on the device if M ≦ Q and N ≦ R; and if M is less than or equal to Q and N is more than or equal to R, determining the maximum brightness threshold of the blue channel as the reference brightness threshold from the maximum brightness thresholds of all the color channels on the slave equipment.

In one embodiment, the target brightness threshold calculation unit 846 is further configured to determine a magnitude relationship between M: N and Q: R if M is greater than or equal to Q and N is greater than or equal to R; if M is not less than Q and R is not less than Q, determining the maximum brightness threshold of the blue channel from the maximum brightness thresholds of all color channels on the slave equipment as a reference brightness threshold; and if M, N is less than or equal to Q, R, determining the maximum brightness threshold of the green channel from the maximum brightness thresholds of the color channels on the slave equipment as a reference brightness threshold.

In one embodiment, the gray-scale value adjusting module 860 is further configured to calculate a ratio between the luminance of each color channel between the slave device and the master device according to the target luminance threshold of each color channel on the slave device and the maximum luminance threshold of each color channel on the master device; calculating the brightness of each color channel of each pixel on the main equipment according to the gray-scale value of each color channel of each pixel on the main equipment and the Gamma curve of each color channel of the main equipment; and calculating the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave equipment according to the brightness of each color channel of each pixel on the master equipment, the brightness ratio of the corresponding color channel between the slave equipment and the master equipment and the Gamma curve of the corresponding color channel of the slave equipment.

In one embodiment, the gray-scale value adjusting module 860 is further configured to calculate the luminance of the corresponding color channel of each pixel on the slave device according to a ratio of the luminance of each color channel of each pixel on the master device to the luminance of the corresponding color channel between the slave device and the master device; and calculating each color channel gray-scale value of each pixel when the picture to be projected is displayed on the slave equipment according to the brightness of the corresponding color channel of each pixel on the slave equipment and the Gamma curve of the corresponding color channel of the slave equipment.

It should be understood that, although the steps in the flowcharts in the above-described figures are shown in order as indicated by the arrows, the steps are not necessarily performed in order as indicated by the arrows. The steps are not performed in the exact order shown and described, and may be performed in other orders, unless explicitly stated otherwise. Moreover, at least some of the steps in the above figures may include multiple sub-steps or multiple stages, which are not necessarily performed at the same time, but may be performed at different times, and the order of performing the sub-steps or stages is not necessarily sequential, but may be performed alternately or alternately with other steps or at least some of the sub-steps or stages of other steps.

The division of each module in the display device of the picture to be projected is only used for illustration, and in other embodiments, the display device of the picture to be projected may be divided into different modules as needed to complete all or part of the functions of the display device of the picture to be projected.

For specific limitations of the display device of the to-be-projected screen, reference may be made to the above limitations on the display method of the to-be-projected screen, and details are not described herein again. All or part of each module in the display device of the picture to be projected can be realized by software, hardware and a combination thereof. The modules can be embedded in a hardware form or independent from a processor in the computer device, and can also be stored in a memory in the computer device in a software form, so that the processor can call and execute operations corresponding to the modules.

In an embodiment, an electronic device is further provided, which includes a memory and a processor, where the memory stores a computer program, and when the computer program is executed by the processor, the processor is enabled to execute the steps of the method for displaying a to-be-projected screen provided in the above embodiments.

Fig. 10 is a schematic diagram of an internal structure of an electronic device in one embodiment. As shown in fig. 10, the electronic device includes a processor and a memory connected by a system bus. Wherein, the processor is used for providing calculation and control capability and supporting the operation of the whole electronic equipment. The memory may include a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The computer program can be executed by a processor to implement a display method of a picture to be projected provided by the above embodiments. The internal memory provides a cached execution environment for the operating system computer programs in the non-volatile storage medium. The electronic device may be any terminal device such as a mobile phone, a tablet computer, a PDA (Personal Digital Assistant), a Point of Sales (POS), a vehicle-mounted computer, and a wearable device.

The implementation of each module in the display device of the screen to be projected provided in the embodiment of the present application may be in the form of a computer program. The computer program may be run on an electronic device or an electronic device. The program modules constituting the computer program may be stored on the electronic device or a memory of the electronic device. Which when executed by a processor, performs the steps of the method described in the embodiments of the present application.

The embodiment of the application also provides a computer readable storage medium. One or more non-transitory computer-readable storage media containing computer-executable instructions that, when executed by one or more processors, cause the processors to perform the steps of a method of displaying a screen to be projected.

A computer program product containing instructions which, when run on a computer, cause the computer to perform a method of displaying a picture to be projected.

Any reference to memory, storage, database, or other medium used by embodiments of the present application may include non-volatile and/or volatile memory. Suitable non-volatile memory can include read-only memory (ROM), Programmable ROM (PROM), Electrically Programmable ROM (EPROM), Electrically Erasable Programmable ROM (EEPROM), or flash memory. Volatile memory can include Random Access Memory (RAM), which acts as external cache memory. By way of illustration and not limitation, RAM is available in a variety of forms, such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (SDRAM), double data rate SDRAM (DDR SDRAM), Enhanced SDRAM (ESDRAM), synchronous Link (Synchlink) DRAM (SLDRAM), Rambus Direct RAM (RDRAM), direct bus dynamic RAM (DRDRAM), and bus dynamic RAM (RDRAM).

The above display examples of the to-be-projected-screen images only express several embodiments of the present application, and the description thereof is more specific and detailed, but not construed as limiting the scope of the present application. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the concept of the present application, which falls within the scope of protection of the present application. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A display method of a picture to be projected is characterized by comprising the following steps:

2. The method according to claim 1, wherein the adjusting the maximum luminance threshold value of each color channel on the slave device according to the maximum luminance threshold value of each color channel on the master device and the maximum luminance threshold value of each color channel on the slave device to obtain the target luminance threshold value of each color channel on the slave device comprises:

3. The method according to claim 1, wherein the adjusting the maximum luminance threshold value of each color channel on the slave device according to the maximum luminance threshold value of each color channel on the master device and the maximum luminance threshold value of each color channel on the slave device to obtain the target luminance threshold value of each color channel on the slave device comprises:

determining a first brightness threshold ratio of the main device according to the maximum brightness threshold of each color channel on the main device; the first brightness threshold ratio is a ratio of a red channel maximum brightness threshold on the main device, a green channel maximum brightness threshold on the main device, and a blue channel maximum brightness threshold on the main device;

determining a second brightness threshold ratio of the slave device according to the maximum brightness threshold of each color channel on the slave device; wherein the second brightness threshold ratio is a ratio of a red channel maximum brightness threshold on the slave device, a green channel maximum brightness threshold on the slave device, and a blue channel maximum brightness threshold on the slave device;

adjusting the maximum brightness threshold of each color channel on the slave equipment according to the first brightness threshold ratio and the second brightness threshold ratio to obtain a target brightness threshold of each color channel on the slave equipment; wherein a ratio between the target luminance threshold values of the respective color channels on the slave device is equal to the first luminance threshold ratio.

4. The method of claim 3, wherein the adjusting the maximum luminance threshold of each color channel on the slave device according to the first luminance threshold ratio and the second luminance threshold ratio to obtain the target luminance threshold of each color channel on the slave device comprises:

respectively carrying out normalization processing on the first brightness threshold ratio and the second brightness threshold ratio, and determining a reference brightness threshold from the maximum brightness threshold of each color channel on the slave device according to the result after the normalization processing;

and when the maximum brightness threshold of each color channel on the slave equipment is adjusted, keeping the reference brightness threshold unchanged, and reducing the maximum brightness thresholds of other color channels except the color channel corresponding to the reference brightness threshold to obtain the target brightness threshold of each color channel on the slave equipment.

5. The method of claim 4, wherein if the first luminance threshold ratio normalization results in L: m: n, the result of the second brightness threshold ratio after normalization is P: q: r is the total number of the carbon atoms in the carbon fiber, wherein L-P-1, M is a ratio between a maximum luminance threshold of a green channel on the master device and a maximum luminance threshold of a red channel on the master device, the N is a ratio between a maximum luminance threshold of a blue channel on the master device and a maximum luminance threshold of a red channel on the master device, the Q is the ratio between the maximum brightness threshold of the green channel on the slave device and the maximum brightness threshold of the red channel on the slave device, the R is the ratio of the maximum brightness threshold of the blue channel on the slave device to the maximum brightness threshold of the red channel on the slave device;

the determining a reference brightness threshold from the maximum brightness thresholds of the respective color channels on the slave device according to the result after the normalization processing includes:

and determining a reference brightness threshold value from the maximum brightness threshold values of the color channels on the slave device according to the size relation between M, N, Q and R.

6. The method according to claim 5, wherein the determining the reference luminance threshold value from the maximum luminance threshold values of the respective color channels on the slave device according to the magnitude relationship between M, N, Q and R comprises:

if M is larger than or equal to Q and N is smaller than or equal to R, determining the maximum brightness threshold of the green channel as a reference brightness threshold from the maximum brightness thresholds of all color channels on the slave equipment;

and if M is larger than or equal to Q and N is larger than or equal to R, determining the maximum brightness threshold of the green channel or the blue channel as a reference brightness threshold from the maximum brightness thresholds of all the color channels on the slave equipment.

7. The method according to claim 5, wherein the determining the reference luminance threshold value from the maximum luminance threshold values of the respective color channels on the slave device according to the magnitude relationship between M, N, Q and R comprises:

and if M is less than or equal to Q and N is more than or equal to R, determining the maximum brightness threshold of the blue channel as a reference brightness threshold from the maximum brightness thresholds of all the color channels on the slave equipment.

8. The method as claimed in claim 5, wherein if M ≧ Q and N ≧ R, determining the maximum luminance threshold of the green channel or the blue channel as the reference luminance threshold from the maximum luminance thresholds of the respective color channels on the slave device comprises:

if M is not less than Q, R, determining the maximum brightness threshold of the blue channel as a reference brightness threshold from the maximum brightness thresholds of the color channels on the slave equipment;

9. The method according to any one of claims 1 to 8, wherein the adjusting the respective color channel gray-scale value of each pixel when the picture to be projected is displayed on the slave device according to the target brightness threshold value of each color channel on the slave device, the maximum brightness threshold value of each color channel on the master device, and the respective color channel gray-scale value of each pixel on the master device comprises:

calculating the brightness ratio of each color channel between the slave device and the master device according to the target brightness threshold of each color channel on the slave device and the maximum brightness threshold of each color channel on the master device;

calculating the brightness of each color channel of each pixel on the main equipment according to the gray-scale value of each color channel of each pixel on the main equipment and the Gamma curve of each color channel of the main equipment;

and calculating the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave equipment according to the brightness of each color channel of each pixel on the master equipment, the brightness ratio of the corresponding color channel between the slave equipment and the master equipment and the Gamma curve of the corresponding color channel of the slave equipment.

10. The method according to claim 9, wherein the calculating the gray-scale value of each color channel of each pixel when the picture to be projected is displayed on the slave device according to the luminance of each color channel of each pixel on the master device, the luminance ratio of the corresponding color channel between the slave device and the master device, and the Gamma curve of the corresponding color channel of the slave device comprises:

calculating the brightness of the corresponding color channel of each pixel on the slave device according to the brightness of each color channel of each pixel on the master device and the brightness ratio of the corresponding color channel between the slave device and the master device;

11. A display device for a picture to be projected, the device comprising:

12. An electronic device comprising a memory and a processor, wherein the memory stores a computer program, and wherein the computer program, when executed by the processor, causes the processor to perform the steps of the method for displaying a screen to be projected as set forth in any one of claims 1 to 10.

13. A computer-readable storage medium, on which a computer program is stored, which, when being executed by a processor, carries out the steps of the method for displaying a picture to be projected according to any one of claims 1 to 10.