CN117011124A - Gain map generation method and device, electronic equipment and medium - Google Patents

Abstract

The application discloses a method and a device for generating a gain map, electronic equipment and a medium, and belongs to the technical field of image processing. The method comprises the following steps: and acquiring first brightness information of the original image, wherein the first brightness information comprises first brightness of at least one pixel point in the original image, each pixel point in the at least one pixel point corresponds to one first brightness, determining brightness gain of the at least one pixel point in the original image according to the first brightness of the at least one pixel point, and generating a gain map according to the brightness gain of the at least one pixel point and the original image.

Description

Gain map generation method, device, electronic equipment and medium

Technical field

The present application belongs to the field of image processing technology, and specifically relates to a method, device, electronic equipment and medium for generating a gain map.

Background technique

In image processing, a gain map is an image that describes the brightness gain in different areas of an image. It is usually a grayscale image of the same dimensions as the original image, where each pixel represents the brightness gain of the corresponding area.

In current technology, after obtaining a high dynamic range original image, the original image is usually stored as a Standard Dynamic Range (SDR) image. However, this is limited by the early screen display capabilities and the current mainstream storage bit width. (8bit), when viewing images through a device, the actual scene appearance, including brightness and color perception, cannot be accurately displayed. In order to solve this problem, as the screen display capabilities increase, gain maps can be used to enhance the dynamic range of the image. Storing the image in the format of SDR image + gain map allows the dynamically adjusted brightness range of the SDR image to be adjusted based on the gain map during subsequent image processing and display, restoring or enhancing the details and color information of the original image.

However, in related technologies, the original image needs to be converted into an SDR image through tone mapping, and then the gain map is determined based on the image data of the original image and the image data of the SDR image. However, some application scenarios do not have a tone mapping module, which makes it impossible to Obtain the image data of the SDR image so that the gain map cannot be obtained.

Contents of the invention

The purpose of the embodiments of the present application is to provide a method, device, electronic device and medium for generating a gain map, which can solve the technical problem of being unable to obtain a gain map in existing scene information that cannot be tone mapped.

In a first aspect, embodiments of the present application provide a method for generating a gain map, which method includes:

Obtain first brightness information of the original image, wherein the first brightness information includes the first brightness of at least one pixel in the original image, and each pixel in the at least one pixel corresponds to a first brightness;

Determine the brightness gain of at least one pixel in the original image according to the first brightness of the at least one pixel;

A gain map is generated based on the brightness gain of the at least one pixel and the original image.

In a second aspect, embodiments of the present application provide a device for generating a gain map, which device includes:

Obtaining module, configured to obtain the first brightness information of the original image, wherein the first brightness information includes the first brightness of at least one pixel in the original image, and each pixel in the at least one pixel corresponds to a first brightness;

a determination module configured to determine the brightness gain of at least one pixel in the original image according to the first brightness of the at least one pixel;

A generating module, configured to generate a gain map according to the brightness gain of the at least one pixel and the original image.

In a third aspect, embodiments of the present application provide an electronic device. The electronic device includes a processor and a memory. The memory stores programs or instructions that can be run on the processor. When the program or instructions are executed by the processor, the implementation is as in the first aspect. The steps of the method are provided.

In a fourth aspect, embodiments of the present application provide a readable storage medium. Programs or instructions are stored on the readable storage medium. When the programs or instructions are executed by a processor, the steps of the method provided in the first aspect are implemented.

In a fifth aspect, embodiments of the present application provide a chip. The chip includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement the method provided in the first aspect.

In a sixth aspect, embodiments of the present application provide a computer program product, the program product is stored in a storage medium, and the program product is executed by at least one processor to implement the method provided in the first aspect.

In the method, device, electronic device and medium for generating the gain map of the present application, after obtaining the first brightness of each pixel in the original image, the brightness gain of each pixel can be determined based on the first brightness of at least one pixel, and A gain map is generated from the brightness gain of each pixel and the original image. Compared with the prior art, which requires tone mapping of the original image to obtain an SDR image to determine the gain map, this application does not need to obtain the image data of the SDR image, and can determine the corresponding gain map through only a single frame of the original image. This gain map The generation method can be applied to a wider range of application scenarios.

Description of the drawings

Figure 1 is a schematic flowchart of a method for generating a gain map provided by an embodiment of the present application;

Figure 2 is a schematic structural diagram of a gain map generating device provided by another embodiment of the present application;

Figure 3 is a schematic structural diagram of an electronic device provided by another embodiment of the present application;

Figure 4 is a schematic diagram of the hardware structure of the electronic device provided in the embodiment of the present application.

Detailed ways

The technical solutions in the embodiments of the present application will be clearly described below with reference to the accompanying drawings in the embodiments of the present application. Obviously, the described embodiments are part of the embodiments of the present application, but not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art fall within the scope of protection of this application.

The terms "first", "second", etc. in the description and claims of this application are used to distinguish similar objects and are not used to describe a specific order or sequence. It is to be understood that the terms so used are interchangeable under appropriate circumstances so that the embodiments of the application can be practiced in sequences other than those illustrated or described herein, and that "first," "second," etc. are distinguished Objects are usually of one type, and the number of objects is not limited. For example, the first object can be one or multiple. In addition, "and/or" in the description and claims indicates at least one of the connected objects, and the character "/" generally indicates that the related objects are in an "or" relationship.

In related technologies, in current technology, after acquiring a high dynamic range original image, the original image is usually stored as a Standard Dynamic Range (SDR) image, and the original image needs to be converted into an SDR image through tone mapping. , and then determine the gain map based on the image data of the original image and the image data of the SDR image. However, in some application scenarios, there may not necessarily be a tone mapping module, such as when the image to be processed is ProRAW, or when the tone mapped image cannot be obtained in the ISP channel. When SDR images are used, this results in the inability to obtain the image data of the SDR image, so that the gain map cannot be obtained based on the image data of the original image and the image data of the SDR image.

In order to solve the above technical problems, this application provides a method for generating a gain map. The method for generating the gain map provided by the embodiments of the present application will be described in detail below with reference to the accompanying drawings through specific embodiments and scenario information.

As shown in Figure 1, Figure 1 is a schematic flowchart of a method for generating a gain map provided by an embodiment of the present application. An embodiment of the present application provides a method for generating a gain map. The method may include:

S101. Obtain the first brightness information of the original image, where the first brightness information includes the first brightness of at least one pixel in the original image, and each pixel in the at least one pixel corresponds to a first brightness. ;

In this embodiment, the original image can be a high dynamic range image that is multi-frame fused, or it can be a high dynamic range image that has not undergone any image processing or compression. Compared with the standard image, the original image has a wider range of brightness. scope. The original image includes at least one pixel, and the first image information includes the first brightness of each pixel in the at least one pixel. The first brightness of the pixel refers to the brightness or gray level of the pixel, which Reflects the light intensity or color brightness represented by the pixel.

For each pixel, the first brightness of the pixel can be determined based on each color channel of the pixel. For example, it can be calculated by the following formula:

Among them, Y represents the first brightness of the pixel, R represents the red channel, Gr represents the green (red difference) channel, Gb represents the green (blue difference) channel, B represents the blue channel, a, b, c and d represent The weighting coefficient of each color channel, each weighting coefficient is greater than 0, and the sum of each weighting coefficient is 1.

S102, determine the brightness gain of at least one pixel in the original image according to the first brightness of the at least one pixel;

In this embodiment, since the original image is usually a high dynamic range image, after acquiring the high dynamic range original image, the original image is usually stored as a Standard Dynamic Range (SDR) image. Due to the current SDR The standard white color of the display is generally 100 nit, and the peak brightness of the current flagship display can be as high as 2000 nit. If the SDR standard display is used directly, the display's brightness range is limited and the human eye's true perception of the actual scene cannot be restored (specific performance Because the brightness of the highlight area is not bright enough and is quite different from the actual scene), it is considered to combine the peak brightness of the display screen and the gain image to restore the details and color of the highlight area of the SDR image to restore the human eye's true perception of the scene. .

The SDR image can be brightened based on the brightness gain of each pixel in the original image. The brightness gain is used to represent the degree of brightening of the pixels in the SDR image. The greater the brightness gain, the higher the degree of brightening of the pixels.

Since each pixel in the SDR image is in a lower brightness range, for the pixels in the original image, the greater the first brightness of the pixel, the greater the corresponding brightness gain needs to be, so that it can be as good as possible Restore the display effect of the original image. Therefore, the brightness gain of the pixel can be determined based on the first brightness of the pixel in the original image, so that the brightness gain of the pixel is positively correlated with the first brightness to ensure the display effect of the displayed image.

S103: Generate a gain map according to the brightness gain of the at least one pixel and the original image.

In this application, the gain map refers to a grayscale image with the same size and outline as the original image. The pixel value of each pixel on the gain map is used to represent the brightness gain of the pixel in the SDR image. Therefore, when determining After obtaining the original image and the brightness gain of each pixel, an image with the same size profile as the original image and the brightness gain of each pixel can be generated, which is a gain map.

After obtaining the gain map, the brightness of different areas of the SDR image can be adjusted to varying degrees by applying the gain map to obtain a display image and enhance the display effect of the display image.

In this application, after obtaining the first brightness of each pixel in the original image, the brightness gain of each pixel can be determined based on the first brightness of at least one pixel, and the gain can be generated from the brightness gain of each pixel and the original image. picture. Compared with the prior art, which requires tone mapping of the original image to obtain an SDR image to determine the gain map, this application does not need to obtain the image data of the SDR image, and can determine the corresponding gain map through only a single frame of the original image. This gain map The generation method can be applied to a wider range of application scenarios.

In some embodiments, S102 includes:

The compression coefficient of each pixel in the original image is determined according to the image area to which each pixel in the original image belongs. The original image includes at least one image area divided based on scene information. Each of the at least one image area The image area corresponds to a kind of scene information of the original image.;

Perform compression processing on the first brightness of the at least one pixel based on the compression coefficient to obtain the second brightness of the at least one pixel;

The brightness gain of the at least one pixel is determined based on the first brightness of the at least one pixel and the second brightness of the at least one pixel.

In this embodiment, the second brightness of each pixel in the original image can be obtained by estimating the degree of compression of the first brightness of each pixel in the original image during the process of dynamic range compression of the original image to obtain the SDR image. , and determine the brightness gain of each pixel based on the first brightness and the second brightness of each pixel. Since the brightness gain reflects the difference between the first brightness and the second brightness, the greater the difference between the first brightness and the second brightness, the greater the brightness gain.

The compression coefficient is used to represent the degree of compression of the first brightness of each pixel. The compression coefficient of each pixel in the original image can be determined based on the scene information in the original image.

For example, a basic coefficient can be determined, and the image area to which each pixel in the original image belongs can be identified, and then the scene information corresponding to the image area can be identified, and the basic coefficient can be adjusted based on the scene information to obtain the compression coefficient of each pixel. The first brightness of each pixel is compressed based on the compression coefficient to obtain the compressed second brightness. In addition, the original image can be divided into at least one image area based on the scene information of the original image in advance, and each image area corresponds to one kind of scene information.

For example, dynamic range compression can be power exponential compression. In this case, the exponent value of the compression function is the compression coefficient. The first exponent can be determined as the basic coefficient. If it is recognized that the scene information of the original image to be compressed is human portrait scene. In this case, if the background of the portrait is brightened to a high degree, the background will be too highlighted and the picture will appear uncoordinated. Therefore, the first index can be reduced to obtain the second index, and the second index can be used as the final compression. coefficient, in this way, a larger second brightness and a smaller brightness gain can be obtained, thereby weakening the brightness of the SDR image.

For another example, dynamic range compression can be log function compression. In this case, the base value of the log function is the compression coefficient, and the first base number can be determined as the base coefficient. If it is recognized that the scene information of the original image to be compressed is human. Like the scene, it is also necessary to reduce the brightness gain of the pixel, so the first base can be reduced to obtain the second base, and the second base can be used as the final compression coefficient. In this way, a larger The second brightness, and the smaller brightness gain, thus weakening the brightness of the SDR image.

In this embodiment, the scene information of the original image can be combined to perform dynamic range compression on the original image to obtain an estimate of the compression coefficient of the SDR image, thereby determining the second brightness of each pixel after compression, and based on the first brightness before compression. The brightness and the compressed second brightness determine the brightness gain of the pixel, thereby accurately controlling the brightness of different areas according to the scenes to which they belong.

In some embodiments, determining the brightness gain of the at least one pixel point based on the first brightness of the at least one pixel point and the second brightness of the at least one pixel point includes:

Calculate the sum of the second brightness and the first value of the target pixel to obtain the first sum value;

Determine a first ratio of the first brightness of the target pixel point and the first sum value as the gain reference of the target pixel point;

Determine the brightness gain of the target pixel according to the gain reference;

Wherein, the target pixel point is any one of the at least one pixel point.

In this embodiment, the gain benchmark refers to the reference standard or reference point of the brightness gain. The gain benchmark of the pixel can be directly determined as the brightness gain of the pixel, or it can be optimized based on the gain benchmark to obtain the final brightness gain.

The gain reference is calculated as follows:

Among them, Y represents the first brightness of the target pixel, Y _GTM represents the second brightness of the target pixel, eps is the first value, and eps is a very small value, such as 1e-6, which is set to avoid Y _GTM being 0. , T represents the gain reference of the target pixel.

In some embodiments, determining the brightness gain of the target pixel according to the gain reference includes:

Determine the target image area to which the target pixel points belong;

Determine the adjustment ratio corresponding to the target scene information of the target image area;

The first product of the adjustment ratio corresponding to the target scene information and the gain reference is determined as the brightness gain of the target pixel point.

In this embodiment, after obtaining the gain reference of each pixel in the original image, the scene information in the original image can be identified, and the original image can be segmented based on different scene information. For the image areas corresponding to different scene information, The gain reference of pixels is adjusted in different ways. Specifically, each type of scene information has a corresponding adjustment ratio, and the gain reference of all pixels in the image area corresponding to the scene information can be adjusted based on the adjustment ratio corresponding to the scene information to obtain the final brightness gain.

For example, if the target scene information corresponding to the target pixel is a yin-yang face, that is, half of the face is brightly illuminated, and the other half is not illuminated, so it is darker. In this case, during the brightening process of the SDR image corresponding to the original image, since the brightness gain of the bright part is usually greater than that of the dark part, the bright half of the face will be brighter, which seriously affects the look and feel of the displayed image. , so it is necessary to reduce the value of the gain reference to obtain a smaller brightness gain. Then, you can obtain the adjustment ratio corresponding to the yin and yang face, and adjust the gain reference value based on the adjustment ratio to obtain a smaller brightness gain.

In this embodiment, the brightness gain can be further adjusted on the basis of the brightness gain and combined with specific scene information, thereby more accurately achieving differential control of the brightness gain of different areas on the image.

In some embodiments, determining the first product of the adjustment ratio corresponding to the target scene information and the gain reference as the brightness gain of the target pixel includes:

The first product of the adjustment ratio corresponding to the target scene information and the gain reference is determined as the brightness gain of the target pixel point.

In this embodiment, for the original image, each pixel point in the original image can be traversed, whether these pixel points correspond to the target scene information, and based on the judgment result, the gain reference of these pixel points is adjusted to the brightness gain.

The adjusted formula is as follows:

GainMap＝Ratio*T*Mask+T*(1-Mask)

Among them, GainMap represents the brightness gain of the pixel, Ratio represents the adjustment ratio, and Mask is used to represent whether the pixel corresponds to the target scene information. If it corresponds to the target scene information, the Mask of the pixel is 1, otherwise it is 0, T It represents the gain reference of the pixel.

That is to say, if the pixel corresponds to the target scene information, the brightness gain of the pixel is the first product of the adjustment ratio corresponding to the target scene information and the gain basis; if the pixel corresponds to the target scene information, the brightness of the pixel The gain is the gain base of the pixel.

In some embodiments, determining the brightness gain of at least one pixel in the original image based on the first brightness of the at least one pixel includes:

Obtain the brightness threshold of the standard dynamic range image corresponding to the original image;

The brightness gain of the at least one pixel is determined according to the first brightness of the at least one pixel and the brightness threshold.

In this embodiment, the brightness threshold refers to the highest brightness that a standard dynamic range image can display. If the first brightness of a pixel in the original image is higher than the brightness threshold, then the process of converting the original image into a standard dynamic range image , the first brightness of the pixel will definitely be compressed, so a corresponding brightness gain needs to be set for the pixel so that the standard dynamic range image can restore the brightness during the brightening process, thereby obtaining a better display effect. . Therefore, the brightness gain of each pixel point can be determined according to the first brightness and the brightness threshold. Specifically, as the difference between the first brightness and the brightness threshold is larger, the degree of compression will be correspondingly larger, that is, a larger brightness gain needs to be determined.

In this embodiment, the above method directly determines the brightness gain through the first brightness of the pixels of the original image and the brightness threshold of the SDR image. Then, during the brightening process, the brightness gain is related to the actual brightness of different areas in the original image. Therefore, it can accurately control the brightness of different areas.

In some embodiments, determining the brightness gain of the at least one pixel point based on the first brightness of the at least one pixel point and the brightness threshold includes:

In the case where the first brightness of the target pixel is greater than the brightness threshold, the sum of the first brightness of the target pixel and the second value is the true number and the third value is the base. Log value, and determine a second log value with the brightness threshold as the true number and the third value as the base;

determining a first difference between the first logarithmic value and the second logarithmic value;

The sum of the first difference value and the fourth value is determined as the brightness gain of the target pixel point.

In some embodiments, determining the brightness gain of the at least one pixel point based on the first brightness of the at least one pixel point and the brightness threshold includes:

When the first brightness of the target pixel is less than or equal to the brightness threshold, the brightness gain of the target pixel is determined to be 1.

In this embodiment, after learning the first brightness of the target pixel and the brightness threshold, the brightness gain of the target pixel can be determined through an interval function. Among them, the third value can be any constant greater than 1 set in advance, which is used to convert the brightness into a log domain value to facilitate subsequent calculations.

Specifically, the interval function is as follows:

Among them, GainMap represents the brightness gain of the target pixel, sdr_threshold represents the fixed brightness threshold, YLog is the log domain expression of the first brightness of the target pixel, log ₂ (sdr _threshold ) is the log domain expression of the brightness threshold, the above interval The third value in the function is 2, and the fourth value is 1.

In addition, there are:

YLog＝log ₂ (Y+1)

Among them, YLog is the log domain expression of the first brightness of the target pixel, Y is the first brightness, and the second value is 1.

It can be seen from the above that when the first brightness of the target pixel is less than or equal to the brightness threshold, the brightness gain of the target pixel can be directly determined as 1. When the first brightness of the target pixel is greater than the brightness threshold, The brightness gain of the target pixel can be determined as the value obtained by adding the difference and 1 between the log domain expression of the first brightness and the log domain expression of the brightness threshold.

For example, in the case where the brightness threshold is 4096, if the first brightness is 4096, then the brightness gain of the target pixel is 1, and if the first brightness is 16384, then the brightness gain of the target pixel is 3.

In some embodiments, after generating a gain map based on the brightness gain of the at least one pixel and the original image, the method further includes:

Determine the maximum brightness gain in the gain map from the brightness gain of the at least one pixel;

Determine the second difference between the maximum brightness gain and the fifth value, and the third difference between the brightness gain of the target pixel and the fifth value;

Determine a third ratio of the third difference to the second difference;

The product of the third ratio and the sixth value is normalized and stored.

In this embodiment, after the gain map is generated, the gain map and the SDR image can be stored together. Specifically, in the process of storing the gain map, the numerical range of the pixel gain of each pixel in the gain map can be mapped to an integer range from 0 to 255, and stored as an 8-bit grayscale image.

The mapping process is shown in the following formula:

maxGain＝max(GainMap)

Among them, maxGain is the maximum brightness gain in the gain map, and max(GainMap) means filtering out the pixel with the largest brightness gain among all pixels.

After obtaining the maximum brightness gain, the maximum brightness gain can be substituted into the following formula:

Among them, GM is the value to be normalized, maxGain is the maximum brightness gain in the gain map, GainMap represents the brightness gain of the target pixel, the fifth value is 1, and the sixth value is 255.

After calculation by the above formula, each brightness gain can be converted into a value to be normalized between 0-255, and then the value to be normalized is normalized to the nearest integer and stored as an 8-bit value. A grayscale image will do.

In this embodiment, by normalizing the gain map to 0 to 255 for storage, it can be represented as a grayscale image, and an 8-bit integer value is used in each pixel to represent the gain information. This representation facilitates the storage and processing of gain maps and facilitates continued use during subsequent image processing. In addition, the maximum value plus normalization method is used to retain the accuracy of the gain map and improve the display fault problem of the display image caused by the accuracy of the gain map.

Figure 2 is a schematic structural diagram of a gain map generating device provided by another embodiment of the present application. As shown in Figure 2, the gain map generating device may include:

Obtaining module 201 is used to obtain the first brightness information of the original image, wherein the first brightness information includes the first brightness of at least one pixel in the original image, and each pixel in the at least one pixel corresponds to a first brightness;

Determining module 202, configured to determine the brightness gain of at least one pixel in the original image according to the first brightness of the at least one pixel;

Generating module 203, configured to generate a gain map according to the brightness gain of the at least one pixel and the original image.

In this application, after obtaining the first brightness of each pixel in the original image, the brightness gain of each pixel can be determined based on the first brightness of at least one pixel, and the gain can be generated from the brightness gain of each pixel and the original image. picture. Compared with the prior art, which requires tone mapping of the original image to obtain an SDR image to determine the gain map, this application does not need to obtain the image data of the SDR image, and can determine the corresponding gain map through only a single frame of the original image. This gain map The generation method can be applied to a wider range of application scenarios.

In another optional example, the determining module 202 includes:

A first determination unit configured to determine the compression coefficient of each pixel in the original image according to the image area to which each pixel in the original image belongs, where the original image includes at least one image area divided based on scene information, the Each image area in at least one image area corresponds to a kind of scene information of the original image;

A first compression unit configured to perform compression processing on the first brightness of the at least one pixel based on the compression coefficient to obtain the second brightness of the at least one pixel;

A second determination unit configured to determine the brightness gain of the at least one pixel point based on the first brightness of the at least one pixel point and the second brightness of the at least one pixel point.

In another optional example, the second determination unit is also used to calculate the sum of the second brightness of the target pixel point and the first numerical value to obtain the first sum value;

The second determination unit is further configured to determine the first ratio of the first brightness of the target pixel point and the first sum value as the gain reference of the target pixel point;

The second determination unit is further configured to determine the brightness gain of the target pixel according to the gain reference;

Wherein, the target pixel point is any one of the at least one pixel point.

In another optional example, the second determining unit is also used to:

Determine the target image area to which the target pixel points belong;

Determine the adjustment ratio corresponding to the target scene information of the target image area;

The first product of the adjustment ratio corresponding to the target scene information and the gain reference is determined as the brightness gain of the target pixel point.

In another optional example, the second determination unit is further configured to determine the first product of the adjustment ratio corresponding to the target scene information and the gain reference as the brightness gain of the target pixel point.

The determination module 202 also includes:

A threshold acquisition unit, configured to acquire the brightness threshold of the standard dynamic range image corresponding to the original image;

A third determination unit configured to determine the brightness gain of the at least one pixel point according to the first brightness of the at least one pixel point and the brightness threshold.

In another optional example, the first determination subunit is further configured to determine whether the first brightness of the target pixel point is the same as the second brightness of the target pixel point when the first brightness of the target pixel point is greater than the brightness threshold. The sum of the numerical values is a true number, and the first logarithmic value is determined with the third value as the base, and the second logarithmic value is determined with the brightness threshold as a true number, and the third value is the base; determining the first The first difference between the log value and the second log value; the sum of the first difference and the fourth value is determined as the brightness gain of the target pixel point.

In another optional example, the first determination subunit is further configured to determine the brightness gain of the target pixel point to be 1 when the first brightness of the target pixel point is less than or equal to the brightness threshold.

In another optional example, the device for generating the gain map further includes:

Screening module 204, configured to determine the maximum brightness gain in the gain map from the brightness gain of the at least one pixel point;

The first calculation module 205 is used to determine the second difference between the maximum brightness gain and the fifth value, and the third difference between the brightness gain of the target pixel and the fifth value;

The second calculation module 206 is used to determine the third ratio of the third difference to the second difference;

The storage module 207 is used to normalize and store the product of the third ratio and the sixth value.

The gain map generating device in the embodiment of the present application may be an electronic device, or may be a component in the electronic device, such as an integrated circuit or a chip. The electronic device may be a terminal or other devices other than the terminal. For example, the electronic device may be a mobile phone, a tablet computer, a notebook computer, a handheld computer, a vehicle-mounted electronic device, a mobile Internet device (MID), or augmented reality (AR)/virtual reality (VR). ) equipment, robots, wearable devices, ultra-mobile personal computers (UMPC), netbooks or personal digital assistants (PDA), etc., and can also be servers, network attached storage (Network Attached Storage, NAS), etc. ), a personal computer (PC), a television (TV), a teller machine or a self-service machine, etc. It can also be a server, a network attached storage (NAS), a personal computer (PC), a TV Television (TV), teller machine or self-service machine, etc. are not specifically limited in the embodiments of this application.

The device for generating the gain map in the embodiment of the present application may be a device with an operating system. The operating system may be an Android operating system, an IOS operating system, or other possible operating systems, which are not specifically limited in the embodiments of this application.

The gain map generation device provided by the embodiment of the present application can implement each process implemented by the method embodiment in Figure 1. To avoid repetition, details will not be described here.

Optionally, as shown in Figure 3, this embodiment of the present application also provides an electronic device 100, including a processor 110 and a memory 119. The processor 110 includes a central processing unit CPU 1101 and a GPU compression processing unit 1102. A program or instruction stored in the memory 119 and executable on the processor 110, which when executed by the processor 110, implements each process of the gain map generating method embodiment and can achieve the same technical effect is To avoid repetition, we will not go into details here.

It should be noted that the electronic devices in the embodiments of the present application include the above-mentioned mobile electronic devices and non-mobile electronic devices.

Please refer to FIG. 4 , which is a schematic diagram of the hardware structure of an electronic device implementing an embodiment of the present application. The electronic device 100 includes but is not limited to: radio frequency unit 121, network module 122, audio output unit 123, input unit 124, sensor 125, display unit 126, user input unit 127, interface unit 128, memory 129, processor 120, etc. part.

Those skilled in the art can understand that the electronic device 120 may also include a power supply (such as a battery) that supplies power to various components. The power supply may be logically connected to the processor 120 through a power management system, thereby managing charging, discharging, and function through the power management system. Consumption management and other functions. The structure of the electronic device shown in Figure 4 does not constitute a limitation on the electronic device. The electronic device may include more or less components than shown in the figure, or combine certain components, or arrange different components, which will not be described again here. .

The input unit 124 is used to obtain the first brightness information of the original image, where the first brightness information includes the first brightness of at least one pixel in the original image, and each pixel in the at least one pixel is A point corresponds to a first brightness;

Processor 120, configured to determine the brightness gain of at least one pixel in the original image according to the first brightness of the at least one pixel;

The processor 120 is configured to generate a gain map according to the brightness gain of the at least one pixel and the original image.

In this application, after obtaining the first brightness of each pixel in the original image, the brightness gain of each pixel can be determined based on the first brightness of at least one pixel, and the gain can be generated from the brightness gain of each pixel and the original image. picture. Compared with the prior art, which requires tone mapping of the original image to obtain an SDR image to determine the gain map, this application does not need to obtain the image data of the SDR image, and can determine the corresponding gain map through only a single frame of the original image. This gain map The generation method can be applied to a wider range of application scenarios.

In another optional example, the processor 120 includes:

A first determination unit configured to determine the compression coefficient of each pixel in the original image according to the image area to which each pixel in the original image belongs, where the original image includes at least one image area divided based on scene information, the Each image area in at least one image area corresponds to a kind of scene information of the original image;

A first compression unit configured to perform compression processing on the first brightness of the at least one pixel based on the compression coefficient to obtain the second brightness of the at least one pixel;

A second determination unit configured to determine the brightness gain of the at least one pixel point based on the first brightness of the at least one pixel point and the second brightness of the at least one pixel point.

In another optional example, the second determination unit is also used to calculate the sum of the second brightness of the target pixel point and the first numerical value to obtain the first sum value;

The second determination unit is further configured to determine the first ratio of the first brightness of the target pixel point and the first sum value as the gain reference of the target pixel point;

The second determination unit is further configured to determine the brightness gain of the target pixel according to the gain reference;

Wherein, the target pixel point is any one of the at least one pixel point.

In another optional example, the second determining unit is also used to:

Determine the target image area to which the target pixel points belong;

Determine the adjustment ratio corresponding to the target scene information of the target image area;

The first product of the adjustment ratio corresponding to the target scene information and the gain reference is determined as the brightness gain of the target pixel point.

In another optional example, the second determination unit is further configured to determine the first product of the adjustment ratio corresponding to the target scene information and the gain reference as the brightness gain of the target pixel point.

The determination module 202 also includes:

A threshold acquisition unit, configured to acquire the brightness threshold of the standard dynamic range image corresponding to the original image;

A third determination unit configured to determine the brightness gain of the at least one pixel point according to the first brightness of the at least one pixel point and the brightness threshold.

In another optional example, the first determination subunit is further configured to determine whether the first brightness of the target pixel point is the same as the second brightness of the target pixel point when the first brightness of the target pixel point is greater than the brightness threshold. The sum of the numerical values is a true number, and the first logarithmic value is determined with the third numerical value as the base, and the second logarithmic value is determined with the brightness threshold as a true number, and the third numerical value is the base; determining the first The first difference between the log value and the second log value; the sum of the first difference and the fourth value is determined as the brightness gain of the target pixel point.

In another optional example, the first determination subunit is further configured to determine the brightness gain of the target pixel point to be 1 when the first brightness of the target pixel point is less than or equal to the brightness threshold.

In another optional example, the device for generating the gain map further includes:

Processor 120, configured to determine the maximum brightness gain in the gain map from the brightness gain of the at least one pixel point;

The processor 120 is configured to determine the second difference between the maximum brightness gain and the fifth value, and the third difference between the brightness gain of the target pixel and the fifth value;

Processor 120, configured to determine a third ratio of the third difference to the second difference;

The memory 129 is used to normalize and store the product of the third ratio and the sixth value.

It should be understood that in the embodiment of the present application, the input unit 124 may include a graphics processor (Graphics Processing Unit, GPU) 1241 and a microphone 1242. The graphics processor 1241 is responsible for the image capture device (such as Process the image data of still pictures or videos obtained by the camera). The display unit 126 may include a display panel 1261, which may be configured in the form of a liquid crystal display, an organic light emitting diode, or the like. The user input unit 127 includes a touch panel 1271 and at least one of other input devices 1272 . Touch panel 1271 is also called a touch screen. The touch panel 1271 may include two parts: a touch detection device and a touch controller. Other input devices 1272 may include, but are not limited to, physical keyboards, function keys (such as volume control keys, switch keys, etc.), trackballs, mice, and joysticks, which will not be described again here.

Memory 129 may be used to store software programs as well as various data. The memory 129 may mainly include a first storage area for storing programs or instructions and a second storage area for storing data, wherein the first storage area may store an operating system, an application program or instructions required for at least one function (such as a sound playback function, Image playback function, etc.) etc. Additionally, memory 129 may include volatile memory or nonvolatile memory, or memory 129 may include both volatile and nonvolatile memory. Among them, the non-volatile memory can be read-only memory (Read-Only Memory, ROM), programmable read-only memory (Programmable ROM, PROM), erasable programmable read-only memory (Erasable PROM, EPROM), electrically removable memory. Erase programmable read-only memory (Electrically EPROM, EEPROM) or flash memory. Volatile memory can be random access memory (RandomAccess Memory, RAM), static random access memory (Static RAM, SRAM), dynamic random access memory (Dynamic RAM, DRAM), synchronous dynamic random access memory (Synchronous DRAM) , SDRAM), double data rate synchronous dynamic random access memory (Double Data Rate SDRAM, DDRSDRAM), enhanced synchronous dynamic random access memory (Enhanced SDRAM, ESDRAM), synchronous link dynamic random access memory (Synch link DRAM, SLDRAM) and Direct Rambus RAM (DRRAM). Memory 129 in embodiments of the present application includes, but is not limited to, these and any other suitable types of memory.

The processor 120 may include one or more processing units; optionally, the processor 120 integrates an application processor and a modem processor, where the application processor mainly handles operations related to the operating system, user interface, application programs, etc., Modem processors mainly process wireless communication signals, such as baseband processors. It can be understood that the above modem processor may not be integrated into the processor 120 .

Embodiments of the present application also provide a readable storage medium. Programs or instructions are stored on the readable storage medium. When the program or instructions are executed by a processor, each process of the gain map generation method embodiment is implemented, and the same can be achieved. The technical effects will not be repeated here to avoid repetition.

Wherein, the processor is the processor in the electronic device in the above embodiment. Readable storage media includes computer-readable storage media, such as computer read-only memory ROM, random access memory RAM, magnetic disks or optical disks.

The embodiment of the present application also provides a chip. The chip includes a processor and a communication interface. The communication interface is coupled to the processor. The processor is used to run programs or instructions to implement each process of the above gain map generation method embodiment, and can achieve The same technical effects are not repeated here to avoid repetition.

It should be understood that the chips mentioned in the embodiments of this application may also be called system-on-chip, system-on-a-chip, system-on-a-chip or system-on-chip, etc.

Embodiments of the present application provide a computer program product. The program product is stored in a storage medium. The program product is executed by at least one processor to implement each process of the above gain map generating method embodiment, and can achieve the same To avoid repetition, the technical effects will not be repeated here.

It should be noted that, in this document, the terms "comprising", "comprises" or any other variations thereof are intended to cover a non-exclusive inclusion, such that a process, method, article or device that includes a series of elements not only includes those elements, It also includes other elements not expressly listed or inherent in the process, method, article or apparatus. Without further limitation, an element defined by the statement "comprises a..." does not exclude the presence of additional identical elements in a process, method, article or apparatus that includes that element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, but may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved. Functions may be performed, for example, the methods described may be performed in an order different from that described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus the necessary general hardware platform. Of course, it can also be implemented by hardware, but in many cases the former is better. implementation. Based on this understanding, the technical solution of the present application can be embodied in the form of a computer software product that is essentially or contributes to the existing technology. The computer software product is stored in a storage medium (such as ROM/RAM, disk , optical disk), including several instructions to cause a terminal (which can be a mobile phone, computer, server, or network device, etc.) to execute the methods described in various embodiments of this application.

The embodiments of the present application have been described above in conjunction with the accompanying drawings. However, the present application is not limited to the above-mentioned specific implementations. The above-mentioned specific implementations are only illustrative and not restrictive. Those of ordinary skill in the art will Inspired by this application, many forms can be made without departing from the purpose of this application and the scope protected by the claims, all of which fall within the protection of this application.

Claims (13)

1. A gain map generation method, characterized by comprising: Obtain first brightness information of the original image, wherein the first brightness information includes the first brightness of at least one pixel in the original image, and each pixel in the at least one pixel corresponds to a first brightness; Determine the brightness gain of at least one pixel in the original image according to the first brightness of the at least one pixel; A gain map is generated based on the brightness gain of the at least one pixel and the original image. 2. The method of claim 1, wherein determining the brightness gain of at least one pixel in the original image according to the first brightness of the at least one pixel includes: The compression coefficient of each pixel in the original image is determined according to the image area to which each pixel in the original image belongs. The original image includes at least one image area divided based on scene information. Each of the at least one image area The image area corresponds to a kind of scene information of the original image; Perform compression processing on the first brightness of the at least one pixel based on the compression coefficient to obtain the second brightness of the at least one pixel; The brightness gain of the at least one pixel is determined based on the first brightness of the at least one pixel and the second brightness of the at least one pixel. 3. The method of claim 2, wherein determining the brightness gain of the at least one pixel point based on the first brightness of the at least one pixel point and the second brightness of the at least one pixel point includes: Calculate the sum of the second brightness and the first value of the target pixel to obtain the first sum value; Determine a first ratio of the first brightness of the target pixel point to the first sum value as the gain reference of the target pixel point; Determine the brightness gain of the target pixel according to the gain reference; Wherein, the target pixel point is any one of the at least one pixel point. 4. The method according to claim 3, wherein determining the brightness gain of the target pixel point according to the gain reference includes: Determine the target image area to which the target pixel points belong; Determine the adjustment ratio corresponding to the target scene information of the target image area; The first product of the adjustment ratio corresponding to the target scene information and the gain reference is determined as the brightness gain of the target pixel point. 5. The method of claim 1, wherein determining the brightness gain of at least one pixel in the original image according to the first brightness of the at least one pixel includes: Obtain the brightness threshold of the standard dynamic range image corresponding to the original image; The brightness gain of the at least one pixel is determined according to the first brightness of the at least one pixel and the brightness threshold. 6. The method of claim 5, wherein determining the brightness gain of the at least one pixel based on the first brightness of the at least one pixel and the brightness threshold includes: In the case where the first brightness of the target pixel is greater than the brightness threshold, the sum of the first brightness of the target pixel and the second value is the true number and the third value is the base. Log value, and determine a second log value with the brightness threshold as the true number and the third value as the base; determining a first difference between the first logarithmic value and the second logarithmic value; The sum of the first difference value and the fourth value is determined as the brightness gain of the target pixel point. 7. The method of claim 5, wherein determining the brightness gain of the at least one pixel based on the first brightness of the at least one pixel and the brightness threshold includes: When the first brightness of the target pixel is less than or equal to the brightness threshold, the brightness gain of the target pixel is determined to be 1. 8. The method according to claim 1, wherein after generating a gain map according to the brightness gain of the at least one pixel and the original image, it further includes: Determine the maximum brightness gain in the gain map from the brightness gain of the at least one pixel; Determine the second difference between the maximum brightness gain and the fifth value, and the third difference between the brightness gain of the target pixel and the fifth value; Determine a third ratio of the third difference to the second difference; The product of the third ratio and the sixth value is normalized and stored. 9. A device for generating a gain map, characterized in that it includes: Obtaining module, configured to obtain the first brightness information of the original image, wherein the first brightness information includes the first brightness of at least one pixel in the original image, and each pixel in the at least one pixel corresponds to a first brightness; a determination module configured to determine the brightness gain of at least one pixel in the original image according to the first brightness of the at least one pixel; A generating module, configured to generate a gain map according to the brightness gain of the at least one pixel and the original image. 10. The device according to claim 9, characterized in that the determining module includes: A first determination unit configured to determine the compression coefficient of each pixel in the original image according to the image area to which each pixel in the original image belongs, where the original image includes at least one image area divided based on scene information, the Each image area in at least one image area corresponds to a kind of scene information of the original image; A first compression unit configured to perform compression processing on the first brightness of the at least one pixel based on the compression coefficient to obtain the second brightness of the at least one pixel; A second determination unit configured to determine the brightness gain of the at least one pixel point based on the first brightness of the at least one pixel point and the second brightness of the at least one pixel point. 11. The device according to claim 9, wherein the determining module further includes: A threshold acquisition unit, configured to acquire the brightness threshold of the standard dynamic range image corresponding to the original image; A third determination unit configured to determine the brightness gain of the at least one pixel point according to the first brightness of the at least one pixel point and the brightness threshold. 12. An electronic device, characterized in that it includes a processor and a memory, the memory stores programs or instructions that can be run on the processor, and when the programs or instructions are executed by the processor, the claims are implemented The steps of the method for generating a gain map according to any one of 1-8. 13. A readable storage medium, characterized in that the readable storage medium stores programs or instructions, and when the programs or instructions are executed by a processor, the gain map according to any one of claims 1-8 is realized. Generate the steps of the method.