CN107888840B - High dynamic range image acquisition method and device - Google Patents

Abstract

The application discloses a method and a device for acquiring high dynamic range images, wherein the method comprises the following steps: acquiring brightness information corresponding to a current scene from an automatic exposure control system; determining a pixel proportion threshold and a brightness threshold corresponding to the current scene according to the brightness information corresponding to the current scene; determining color channel histograms corresponding to the current scene, wherein each color channel histogram comprises a corresponding relation between different brightness and pixel proportions under each color channel; determining whether the current scene is backlight shooting or not according to a pixel proportion threshold value, a brightness threshold value and each color channel histogram corresponding to the current scene; and when the current scene is determined to be backlight shooting, acquiring a high dynamic range image of the current scene by using a high dynamic range image shooting mode. The method improves the accuracy of backlight detection of the shooting scene, further ensures the quality of the shooting picture and improves the user experience.

Description

High dynamic range image acquisition method and device

technical field

The present application relates to the technical field of exposure processing, and in particular, to a high dynamic range image acquisition method and device.

Background technique

At present, the functions of various smart terminals are more and more diversified, and users can take pictures through the camera of the terminal device. Especially when the shooting environment is in backlight, the camera will automatically switch the shooting mode to a high dynamic range image (High Dynamic Range, referred to as: HDR) mode to take a picture, so as to obtain a high-quality image.

In a practical application process, the terminal device generally detects the shooting environment based on a color coding space (YUV) to determine whether the current shooting environment is a backlight environment. However, the YUV data is obtained after a series of processing by the Image Signal Processor (ISP), which will cause the data in the YUV to not fully reflect the current shooting environment, which will lead to the failure of the shooting environment. There is an error in the detection, which affects the quality of the captured image.

SUMMARY OF THE INVENTION

The present application aims to solve one of the above-mentioned technical defects at least to a certain extent.

Therefore, the first objective of the present application is to propose a high dynamic range image acquisition method, which improves the accuracy of backlight detection of the shooting scene, thereby ensuring the quality of the shooting picture and improving the user experience.

The second object of the present application is to provide a high dynamic range image acquisition device.

The third objective of the present application is to provide a terminal device.

A fourth object of the present application is to propose a computer-readable storage medium.

In order to achieve the above purpose, the method for obtaining a high dynamic range image according to the embodiment of the first aspect of the present application includes: obtaining brightness information corresponding to the current scene from an automatic exposure control system; determining the brightness information corresponding to the current scene according to the brightness information corresponding to the current scene the pixel ratio threshold and the brightness threshold corresponding to the current scene; determine each color channel histogram corresponding to the current scene, wherein each color channel histogram includes the corresponding relationship between different brightness and pixel ratio under each color channel; according to the current scene The pixel ratio threshold, brightness threshold and each color channel histogram corresponding to the scene determine whether the current is backlit shooting; when it is determined that the current is backlit shooting, the high dynamic range image of the current scene is obtained by using the high dynamic range image shooting mode.

In order to achieve the above purpose, the high dynamic range image acquisition device according to the embodiment of the second aspect of the present application includes: a first acquisition module for acquiring brightness information corresponding to a current scene from an automatic exposure control system; a first determination module, is used to determine the pixel ratio threshold and the brightness threshold corresponding to the current scene according to the brightness information corresponding to the current scene; the second determination module is used to determine the histogram of each color channel corresponding to the current scene, wherein each color channel The histogram includes the corresponding relationship between different brightness and pixel ratio under each color channel; the third determination module is used for determining whether the current scene is a backlight shooting according to the pixel ratio threshold value, brightness threshold value and the histogram of each color channel corresponding to the current scene ; a second acquisition module, configured to acquire a high dynamic range image of the current scene by using a high dynamic range image shooting mode when it is determined that the current shooting is against the light.

In order to achieve the above purpose, the terminal device according to the embodiment of the third aspect of the present application includes: a memory, a processor, and a camera module; the camera module is used to collect images in the current scene; the memory is used to store available Execute program code; the processor is configured to read the executable program code stored in the memory to run a program corresponding to the executable program code, so as to implement the high dynamic performance described in the embodiment of the first aspect Range image acquisition method.

To achieve the above purpose, the computer-readable storage medium of the fourth aspect of the present application stores a computer program thereon, and when the computer program is executed by the processor, implements the high dynamic range image acquisition method described in the first aspect.

The technical solution disclosed in the present application has the following beneficial effects:

By obtaining the brightness information corresponding to the current scene from the automatic exposure control system, and according to the obtained brightness information corresponding to the current scene, the pixel ratio threshold and brightness threshold corresponding to the current scene are determined, and the histogram of each color channel corresponding to the current scene is determined. Then, according to the pixel ratio threshold, brightness threshold and the histogram of each color channel corresponding to the current scene, determine whether the current scene is backlit shooting. If it is determined that the current scene is backlit shooting, use the high dynamic range image shooting mode to obtain the high dynamic range of the current scene. image. As a result, the accuracy of the backlight detection of the shooting scene is improved, thereby ensuring the quality of the shooting picture and improving the user experience. .

Additional aspects and advantages of the present application will be set forth, in part, in the following description, and in part will be apparent from the following description, or learned by practice of the present application.

Description of drawings

The above and/or additional aspects and advantages of the present application will become apparent and readily understood from the following description of embodiments taken in conjunction with the accompanying drawings, wherein,

1 is a flowchart of a method for acquiring a high dynamic range image according to an embodiment of the present application;

2 is a schematic diagram of dividing a shooting scene according to an embodiment of the present application;

3(a) is a schematic diagram of a red channel histogram according to an embodiment of the present application;

3(b) is a schematic diagram of a green channel histogram according to an embodiment of the present application;

Figure 3(c) is a schematic diagram of a blue channel histogram according to an embodiment of the present application;

Fig. 4 (a) - Fig. 4 (c) is the channel histogram of each color channel under the backlight scene of an embodiment of the present application;

5 is a flowchart of a method for acquiring a high dynamic range image according to another embodiment of the present application;

6 is a schematic structural diagram of a device for acquiring a high dynamic range image according to an embodiment of the present application;

FIG. 7 is a schematic structural diagram of a terminal device according to an embodiment of the present application.

Detailed ways

The following describes in detail the embodiments of the present application, examples of which are illustrated in the accompanying drawings, wherein the same or similar reference numerals refer to the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary, and are intended to be used to explain the present application, but should not be construed as a limitation to the present application.

In order to solve the problem in the related art, when the terminal device detects the current shooting scene based on YUV, since the YUV data is obtained after a series of processing by the image processor, the YUV data cannot completely reflect the current shooting environment, so In order to solve the problem of errors in the detection of the shooting environment and affect the quality of the captured images, a high dynamic range image acquisition method is proposed.

The method for obtaining a high dynamic range image provided by the present application obtains brightness information corresponding to the current scene from an automatic exposure control system (AutoExposure Control, AEC for short), and then determines the corresponding brightness of the current scene according to the brightness information corresponding to the current scene. and determine the histogram of each color channel corresponding to the current scene, wherein the histogram of each color channel includes the corresponding relationship between different brightness and pixel ratio under each color channel, and then according to the pixel ratio threshold corresponding to the current scene , brightness threshold, and the histogram of each color channel to determine whether the current scene is backlit shooting. When it is determined that the current scene is backlit shooting, the high dynamic range image shooting mode is used to obtain a high dynamic range image of the current scene. As a result, the accuracy of the backlight detection of the shooting scene is improved, the quality of the shooting picture is ensured, and the user experience is improved.

The following describes a method for obtaining an exposure compensation value of a high dynamic range image according to an embodiment of the present application with reference to the accompanying drawings.

FIG. 1 is a flowchart of a method for acquiring a high dynamic range image according to an embodiment of the present application.

As shown in FIG. 1, the high dynamic range image acquisition method of the present application may include the following steps:

Step 101: Obtain brightness information corresponding to the current scene from an automatic exposure control system.

Specifically, the high dynamic range image acquisition method provided by the embodiment of the present application may be executed by the high dynamic range image acquisition apparatus provided by the present application, and the above-mentioned apparatus is configured in a terminal device to control the detection of the shooting scene.

The terminal device in this embodiment may be any hardware device with a photographing function, such as a smart phone, a camera, a personal computer (PC for short), etc., which is not specifically limited in the present invention.

Specifically, in practical applications, when a terminal device is used to perform a shooting operation on a shooting area, the AEC can perform automatic exposure compensation processing on the shooting image according to the brightness of the shooting scene. Therefore, in this embodiment, the brightness information corresponding to the current scene can be directly obtained from the AEC.

Wherein, in this embodiment, the acquired brightness information may be represented by any one of the following information: luxindex, or iso, or gain value, which is not specifically limited in this application.

Step 102: Determine a pixel ratio threshold and a brightness threshold corresponding to the current scene according to the brightness information corresponding to the current scene.

It should be noted that since the same object has different characteristics when it is in a backlight state in shooting scenes of different brightness, in order to make the determined pixel ratio threshold and brightness threshold corresponding to the current scene more accurate, the The scene is roughly divided, and the pixel ratio threshold and the brightness threshold are respectively set for the divided scene.

For example, according to the brightness of the shooting scene, the shooting scenes can be divided into three, namely, high-brightness scenes, medium-brightness scenes, and low-brightness scenes. The scene division results are shown in FIG. 2 for details.

The high-brightness scene may be an outdoor area with good light, the medium-brightness scene may be an indoor area with good light, and the low-brightness scene may be an area with poor light at night, etc., which are not specifically limited in this application.

After the different scenes are divided, this embodiment may further set a pixel ratio threshold and a brightness threshold for each scene.

Wherein, the pixel ratio threshold and brightness threshold of each scene can be adaptively set according to actual usage requirements, which are not specifically limited in this application.

Further, after scene division is performed on the shooting scene, and the corresponding pixel ratio threshold and brightness threshold are set for each scene, the present embodiment may separate the brightness information corresponding to the current scene obtained in step 101 with each of the divided scenes. Matching is performed to determine the pixel ratio threshold and brightness threshold corresponding to the current scene.

In specific implementation, the target brightness range corresponding to the current scene can be determined according to the corresponding relationship between the preset brightness threshold and the brightness range of each scene; then, according to the preset brightness range and the pixel ratio threshold and brightness threshold corresponding relationship, Determine the pixel ratio threshold and the brightness threshold corresponding to the target brightness range.

That is to say, in this embodiment, first, according to the acquired brightness information of the current scene, matching is performed in the brightness range of different scenes, and the scene corresponding to the current scene is determined according to the successfully matched brightness range, and then the scene corresponding to the current scene is determined according to the brightness range of the corresponding scene. The preset pixel ratio threshold and brightness threshold.

For example, if the acquired brightness information corresponding to the current scene is 3 lux, and the three pre-divided scenes are night, indoor, and outdoor, respectively, and the corresponding brightness ranges of the above three scenes are: 0.001~0.3lux , 100～1000lux, more than 1000lux. Then, the brightness information of 3 can be matched with the brightness ranges of 0.001 to 0.3 lux, 100 to 1000 lux, and greater than 1000 lux corresponding to the above three scenes, and it is determined that the brightness information of the current scene belongs to the brightness range of 100 to 1000 lux. Then, according to the brightness range of 100-1000 lux, it is determined that the current scene belongs to the room, and then the pixel ratio threshold and brightness threshold corresponding to the room can be obtained.

Step 103: Determine each color channel histogram corresponding to the current scene, wherein each color channel histogram includes the corresponding relationship between different luminances and pixel ratios under each color channel.

Specifically, the histogram of each color channel corresponding to the current scene may be determined according to the RGB data, which will not be repeated in this embodiment.

It should be noted that if the RGB data obtained in this embodiment includes three color channels of red (R), green (G), and blue (B), then the corresponding determined histograms of each color channel are three, respectively is the histogram of the red channel, the histogram of the green channel, and the histogram of the blue channel.

Further, the above-determined histograms of the three color channels can be found in Fig. 3. Fig. 3(a) is the histogram of the red channel, Fig. 3(b) is the histogram of the green channel, and Fig. 3(c) is the histogram of the green channel. Blue channel histogram. Among them, in the histogram of each color channel, the x-axis represents the image brightness, and the y-axis represents the pixel ratio of each pixel in the image under the brightness.

If the RGB data obtained in this embodiment includes four color channels, R, Gr, Gb, and B, the corresponding determined color channel histograms are four, which are the red channel histogram and the green (Gr) channel histogram respectively. , green (Gb) channel histogram, and blue channel histogram.

Step 104 , according to the pixel ratio threshold value, the brightness threshold value, and the histogram of each color channel corresponding to the current scene, determine whether the current scene is shooting against backlight.

It should be noted that, due to the backlight scene, the histogram of each color channel, usually in the form shown in Figure 4(a) - Figure 4(c), is a "bimodal" distribution, that is, most of the pixels are concentrated in the lowest brightness and The position of the highest brightness.

Among them, Fig. 4(a) is the histogram of the red channel under the backlight scene, Fig. 4(b) is the histogram of the green channel under the backlight scene, and Fig. 4(c) is the histogram of the blue channel under the backlight scene. Among them, in the histogram of each color channel, the x-axis represents the image brightness, and the y-axis represents the pixel ratio of each pixel in the image under the brightness.

Therefore, the pixel ratio threshold in this embodiment may include two, which are the first pixel ratio threshold and the second pixel ratio threshold respectively.

Correspondingly, the brightness threshold also includes two, which are a first brightness threshold and a second brightness threshold.

In addition, the pixel ratio threshold and the brightness threshold are set corresponding to each other, that is, the first pixel ratio threshold corresponds to the first brightness threshold, and the second pixel ratio threshold corresponds to the second brightness threshold.

Therefore, after the histogram of the current scene is obtained, it can be determined whether the current scene is shot against the light according to the histogram of the current scene. Specifically, the above step 104 can be implemented in the following ways:

According to the direction of brightness from low to high and from high to low, count the sum of the pixel ratio values in the histogram of each color channel in turn;

Determine each first brightness value corresponding to each color channel when the sum of the pixel ratio values from low to high reaches the first pixel ratio threshold according to the brightness;

Determine each second brightness value corresponding to each color channel when the sum of the pixel ratio values from high to low reaches the second pixel ratio threshold according to the brightness;

If the first brightness value corresponding to any color channel is less than the first brightness threshold, and the second brightness value is greater than the second brightness threshold, it is determined that the shooting is currently in backlight.

For example, if the first pixel ratio threshold is 6%, the corresponding first brightness threshold is 10, the second pixel ratio threshold is 10%, the corresponding second brightness threshold is 230, and the histogram of each color channel is the red channel. Histogram, Green Channel Histogram, and Blue Channel Histogram.

After analyzing the histogram of the red channel, the histogram of the green channel and the histogram of the blue channel, we can see that in the histogram of the red channel, when the brightness changes from 0 to 255, when the pixel ratio threshold reaches 6%, the corresponding first brightness RL= 8; In the histogram of the green channel, when the brightness changes from 0 to 255, and the pixel ratio threshold reaches 6%, the corresponding first brightness GL=11; in the histogram of the blue channel, when the brightness changes from 0 to 255, the pixel ratio When the threshold value reaches 6%, the corresponding first brightness BL=15.

Correspondingly, in the histogram of the red channel, when the brightness changes from 255 to 0, and the pixel ratio threshold reaches 10%, the corresponding first brightness RL=234; in the histogram of the green channel, when the brightness changes from 255 to 0, the pixel ratio When the threshold reaches 10%, the corresponding first brightness GL=221; in the blue channel histogram, when the brightness changes from 255 to 0, when the pixel ratio threshold reaches 10%, the corresponding first brightness BL=205;

Therefore, it can be seen that if the first brightness value of the red channel histogram is less than the first brightness threshold, and the second brightness value is greater than the second brightness threshold, it is determined that the current shooting is against backlight.

Step 105 , when it is determined that the current shooting is against the light, use the high dynamic range image shooting mode to acquire a high dynamic range image of the current scene.

Specifically, the exposure compensation value corresponding to the current scene can be determined according to the histogram of each color channel corresponding to the current scene; the normal exposure image, underexposure image and overexposure image corresponding to the current scene are obtained based on the exposure compensation value; The underexposed image and the overexposed image are fused to generate a high dynamic range image of the current scene.

In specific implementation, the underexposure degree and overexposure degree of the current scene can be determined according to the corresponding relationship between different brightness and pixel ratio under the histogram of each color channel, the normal exposure brightness threshold value and the pixel ratio threshold value, and then based on the degree of underexposure and the degree of overexposure. The overexposure level queries the preset exposure compensation mapping table to determine the underexposure compensation value and overexposure compensation value of the current scene.

Further, after determining the underexposure compensation value and the overexposure compensation value of the current scene, the present embodiment can obtain the overexposure image and the underexposure image of the current scene respectively according to the underexposure compensation value and the overexposure compensation value. Then the acquired normal exposure image, underexposure image and overexposure image are image-fused to obtain a high-quality high dynamic range image that can display more image details.

It can be understood that the high dynamic range image acquisition device of the present application determines the pixel ratio threshold and brightness threshold corresponding to the current scene by acquiring the brightness information corresponding to the current scene, and determines the histogram of each color channel corresponding to the current scene, and then according to the pixel ratio threshold value and the brightness threshold value corresponding to the current scene are determined. The ratio threshold, brightness threshold and the histogram of each color channel determine whether the current shooting is backlit, thus ensuring that when the current shooting is against the backlight, the current shooting area can be shot under exposure and overexposure by starting the high dynamic range image shooting mode. And the normal exposure image is taken, and then the above three images are fused to obtain a high dynamic range image, so that the details on the image can be displayed more clearly, the real visual effect of the current scene can be more truly reflected, and the quality of the image can be improved.

In the high dynamic range image acquisition method of the embodiment of the present application, the brightness information corresponding to the current scene is acquired from the automatic exposure control system, and the pixel ratio threshold corresponding to the current scene and the threshold value of the pixel ratio corresponding to the current scene are determined according to the acquired brightness information corresponding to the current scene. Brightness threshold, and determine the histogram of each color channel corresponding to the current scene, and then determine whether the current scene is backlit shooting according to the pixel ratio threshold, brightness threshold and each color channel histogram corresponding to the current scene. If it is determined that the current scene is backlit shooting, use The HDR image capture mode acquires a HDR image of the current scene. As a result, the accuracy of the backlight detection of the shooting scene is improved, thereby ensuring the quality of the shooting picture and improving the user experience.

It can be seen from the above analysis that the present application determines the pixel ratio threshold and brightness threshold corresponding to the current scene, and the corresponding color channel histograms according to the brightness information corresponding to the current scene, and then according to the determined pixel ratio threshold, brightness threshold and each color channel Histogram, to determine whether the current is backlit shooting. In a possible implementation scenario of the present application, if the shooting scene includes a human face, in order to ensure the effect of the human face area in the captured image, AEC will automatically perform reasonable exposure control on the image, so as to ensure that the captured image does not too dark, where the background may appear overexposed. Therefore, in the embodiment of the present application, when detecting whether the shooting scene is backlit, if the current shooting scene includes a human face, the detection threshold can be appropriately adjusted based on the above reasons, so that the detection of whether the current is backlit is more accurate. The resulting images are of higher quality. The above situation will be described in detail below with reference to FIG. 5 .

FIG. 5 is a flowchart of another high dynamic range image acquisition method of the present application.

As shown in FIG. 5 , the high dynamic range image acquisition method of the present application may include the following steps:

Step 501: Obtain brightness information corresponding to the current scene from an automatic exposure control system.

Step 502: Determine a pixel ratio threshold and a brightness threshold corresponding to the current scene according to the brightness information corresponding to the current scene.

Step 503, performing face detection on the current scene.

During specific implementation, a face detection operation can be performed on the shooting picture of the current scene through a face recognition technology (Face Recognition Technology).

Among them, the face recognition technology may include a variety of face detection methods, such as feature-based face detection, template matching method, face detection based on adaboost algorithm, etc., which are not specifically limited in this application. .

Step 504, if it is determined that the current scene includes a face region, adjust the pixel ratio threshold and the brightness threshold.

It should be noted that, when it is determined that the current scene includes a face area, the face part is reasonably exposed through AEC, so that the dark part in the shooting picture may not be too dark, while the background is usually overexposed. This can easily lead to an increase in the overall brightness of the captured image.

However, after the overall brightness of the photographed image is increased, if the pixel ratio threshold and the brightness threshold determined in step 402 are continued to be used to judge whether the photograph is currently being photographed against the backlight, there will be a problem of inaccurate judgment.

Therefore, in order to avoid the occurrence of the above problems, when it is determined that there is a face area in the current scene, the present application appropriately adjusts the pixel ratio threshold and the brightness threshold determined in step 502, so as to make the detection accuracy of whether the current scene is a backlight shooting. higher.

Wherein, since the pixels in the captured picture are relatively concentrated in the lowest and highest brightness positions, the pixel ratio threshold in this embodiment may include a first pixel ratio threshold and a second pixel ratio threshold.

Correspondingly, the brightness threshold may also include a first brightness threshold and a second brightness threshold.

In addition, the pixel ratio threshold and the brightness threshold are set corresponding to each other, that is, the first pixel ratio threshold corresponds to the first brightness threshold, and the second pixel ratio threshold corresponds to the second brightness threshold.

During specific implementation, when adjusting the pixel ratio threshold and the brightness threshold, the present application may include:

Decrease the first pixel ratio threshold, or increase the first brightness threshold;

Increase the second pixel scale threshold, or increase the second brightness threshold.

It should be noted that the reason why the first pixel ratio threshold is reduced or the first brightness threshold is increased in this application is because the brightness in the shooting image has been increased after the exposure compensation of the AEC including the face area. When still using the previously determined first pixel ratio threshold to determine whether the current shooting is against the light, it may occur that the originally dark pixels are no longer dark, resulting in an error in the judgment.

Similarly, the increase of the first brightness threshold is also to prevent errors in the final determination of whether the shooting is backlit after exposure compensation of the AEC.

Similarly, after the exposure compensation of the AEC, the overall brightness of the shooting image is increased, and the proportion of pixels in the brightest position will increase, so it is necessary to increase the second pixel ratio threshold, or increase the second pixel ratio threshold. Brightness threshold.

Step 505: Determine each color channel histogram corresponding to the current scene, wherein each color channel histogram includes the corresponding relationship between different luminances and pixel ratios under each color channel.

Step 506 , according to the adjusted pixel ratio threshold, brightness threshold and the histogram of each color channel, determine whether it is currently shooting against backlight.

Step 507 , when it is determined that the current shooting is against the light, use the high dynamic range image shooting mode to acquire a high dynamic range image of the current scene.

In the high dynamic range image acquisition method of the embodiment of the present application, after determining the pixel ratio threshold and the brightness threshold corresponding to the current scene, face detection is performed on the current scene. If it is detected that there is a face area in the current scene, the The pixel ratio threshold and brightness threshold are adjusted, thereby improving the accuracy of backlight detection of the shooting scene, thereby ensuring the quality of the shooting picture and improving the user experience.

In order to realize the above embodiments, the present invention also provides a high dynamic range image acquisition device.

FIG. 6 is a schematic structural diagram of an apparatus for acquiring a high dynamic range image according to an embodiment of the present invention.

As shown in FIG. 6 , the high dynamic range image acquisition device of the present application includes: a first acquisition module 11 , a first determination module 12 , a second determination module 13 , a third determination module 14 and a second acquisition module 15 .

Wherein, the first acquisition module 11 is used to acquire the brightness information corresponding to the current scene from the automatic exposure control system;

The first determining module 12 is configured to determine, according to the brightness information corresponding to the current scene, a pixel ratio threshold and a brightness threshold corresponding to the current scene;

The second determination module 13 is configured to determine the histogram of each color channel corresponding to the current scene, wherein the histogram of each color channel includes the corresponding relationship between different luminances and pixel ratios under each color channel;

The third determination module 14 is configured to determine whether the current scene is backlit shooting according to the pixel ratio threshold value, the brightness threshold value and the histogram of each color channel corresponding to the current scene;

The second acquisition module 15 is configured to acquire a high dynamic range image of the current scene by using a high dynamic range image shooting mode when it is determined that the current scene is shot against the light.

Further, in another embodiment of the present application, the pixel ratio threshold includes: a first pixel ratio threshold, a first brightness threshold, a second pixel ratio threshold, and a second brightness threshold corresponding to each other;

The third determination module 14 includes:

a statistical unit, configured to count the sum of the pixel ratio values in the histogram of each color channel in turn according to the direction of brightness from low to high and from high to low;

a first determining unit, configured to determine each first brightness value corresponding to each color channel when the sum of the pixel ratio values from low to high brightness reaches the first pixel ratio threshold;

a second determining unit, configured to determine each second brightness value corresponding to each color channel when the sum of the pixel ratio values from high to low brightness reaches the second pixel ratio threshold;

The third determining unit is configured to determine that the current shooting is in backlight if the first brightness value corresponding to any color channel is less than the first brightness threshold and the second brightness value is greater than the second brightness threshold.

It should be noted that the foregoing explanations of the embodiment of the high dynamic range image acquisition method are also applicable to the high dynamic range image acquisition device of this embodiment, and the implementation principle thereof is similar, which will not be repeated here.

In the high dynamic range image acquisition device provided in this embodiment, the brightness information corresponding to the current scene is acquired from the automatic exposure control system, and according to the acquired brightness information corresponding to the current scene, the pixel ratio threshold and the corresponding pixel ratio of the current scene are determined. Brightness threshold, and determine the histogram of each color channel corresponding to the current scene, and then determine whether the current scene is backlit shooting according to the pixel ratio threshold, brightness threshold and each color channel histogram corresponding to the current scene. If it is determined that the current scene is backlit shooting, use The HDR image capture mode acquires a HDR image of the current scene. As a result, the accuracy of the backlight detection of the shooting scene is improved, thereby ensuring the quality of the shooting picture and improving the user experience.

In order to realize the above embodiments, the present invention also provides a terminal device.

FIG. 7 is a schematic structural diagram of a terminal device according to an embodiment of the present invention.

Referring to FIG. 7 , the terminal device of the present application includes a memory 21, a processor 22 and a camera module 23;

The camera module 23 is used to collect images in the current scene;

The memory 21 is used to store executable program codes;

The processor 22 is configured to read the executable program code stored in the memory 21 to run a program corresponding to the executable program code, so as to realize the high dynamic range image acquisition described in the embodiment of the first aspect method. The high dynamic range image acquisition method includes: acquiring brightness information corresponding to the current scene from an automatic exposure control system; determining a pixel ratio threshold and a brightness threshold corresponding to the current scene according to the brightness information corresponding to the current scene; determining Each color channel histogram corresponding to the current scene, wherein each color channel histogram includes the corresponding relationship between different brightness and pixel ratio under each color channel; according to the pixel ratio threshold, brightness threshold and each color channel corresponding to the current scene The histogram is used to determine whether the current scene is backlit shooting; when it is determined that the current scene is backlit shooting, a high dynamic range image of the current scene is acquired by using a high dynamic range image shooting mode.

The terminal device in this embodiment may be any hardware device with a photographing function, such as a smart phone, a camera, a personal computer (PC for short), etc., which is not specifically limited in the present invention.

It should be noted that, the foregoing explanation of the embodiment of the method for acquiring a high dynamic range image is also applicable to the terminal device of this embodiment, and the implementation principle thereof is similar, which will not be repeated here.

In the terminal device provided in this embodiment, the brightness information corresponding to the current scene is obtained from the automatic exposure control system, and the pixel ratio threshold and the brightness threshold corresponding to the current scene are determined according to the obtained brightness information corresponding to the current scene, and Determine the histogram of each color channel corresponding to the current scene, and then determine whether the current scene is backlit shooting according to the pixel ratio threshold, brightness threshold, and color channel histogram corresponding to the current scene. If it is determined that the current scene is backlit shooting, use the high dynamic range image Capture mode to acquire a high dynamic range image of the current scene. As a result, the accuracy of the backlight detection of the shooting scene is improved, thereby ensuring the quality of the shooting picture and improving the user experience.

In order to realize the above embodiments, the present invention also provides a computer-readable storage medium.

The computer-readable storage medium has a computer program stored thereon, and when the program is executed by the processor, implements the high dynamic range image acquisition method of the embodiment of the first aspect. The high dynamic range image method includes: obtaining brightness information corresponding to the current scene from an automatic exposure control system; determining a pixel ratio threshold and a brightness threshold corresponding to the current scene according to the brightness information corresponding to the current scene; Each color channel histogram corresponding to the current scene, wherein each color channel histogram includes the corresponding relationship between different brightness and pixel ratio under each color channel; according to the pixel ratio threshold, brightness threshold and each color channel histogram corresponding to the current scene Figure, determine whether the current is backlit shooting; when it is determined that the current is backlit shooting, use the high dynamic range image shooting mode to acquire the high dynamic range image of the current scene.

In the present invention, unless otherwise expressly specified and limited, terms such as "arrangement" and "connection" should be understood in a broad sense, for example, it may be a mechanical connection or an electrical connection; it may be a direct connection or an electrical connection. The intermediary is indirectly connected, and may be the internal communication between two elements or the interaction relationship between the two elements, unless otherwise expressly defined. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

In the description of this specification, description with reference to the terms "one embodiment," "some embodiments," "example," "specific example," or "some examples", etc., mean specific features described in connection with the embodiment or example , structure, material or feature is included in at least one embodiment or example of the present invention.

In addition, the terms "first" and "second" are only used for descriptive purposes, and should not be construed as indicating or implying relative importance or implying the number of indicated technical features. Thus, a feature delimited with "first", "second" may expressly or implicitly include at least one of that feature.

Any description of a process or method in the flowcharts or otherwise described herein may be understood to represent a module, segment or portion of code comprising one or more executable instructions for implementing a specified logical function or step of the process , and the scope of the preferred embodiments of the present invention includes alternative implementations in which the functions may be performed out of the order shown or discussed, including performing the functions substantially concurrently or in the reverse order depending upon the functions involved, which should It is understood by those skilled in the art to which the embodiments of the present invention belong.

It should be understood that various parts of the present invention may be implemented in hardware, software, firmware or a combination thereof. In the above-described embodiments, various steps or methods may be implemented in software or firmware stored in memory and executed by a suitable instruction execution system. For example, if implemented in hardware, as in another embodiment, it can be implemented by any one or a combination of the following techniques known in the art: Discrete logic circuits, application specific integrated circuits with suitable combinational logic gates, Programmable Gate Arrays (PGA), Field Programmable Gate Arrays (FPGA), etc.

Those skilled in the art can understand that all or part of the steps carried by the methods of the above embodiments can be completed by instructing the relevant hardware through a program, and the program can be stored in a computer-readable storage medium, and the program can be stored in a computer-readable storage medium. When executed, one or a combination of the steps of the method embodiment is included.

The above-mentioned storage medium may be a read-only memory, a magnetic disk or an optical disk, and the like. Although the embodiments of the present invention have been shown and described above, it should be understood that the above-mentioned embodiments are exemplary and should not be construed as limiting the present invention. Embodiments are subject to variations, modifications, substitutions and variations.

Claims (8)

1. a kind of high-dynamic-range image acquisition method characterized by comprising

From automatic exposure control system, luminance information corresponding with current scene is obtained；

According to the corresponding luminance information of the current scene, the corresponding pixel ratio threshold value of the current scene and luminance threshold are determined Value；

Determine the corresponding each color channel histograms of the current scene, wherein each color channel histograms include that each color is logical The corresponding relationship of different brightness and pixel ratio under road；

According to the corresponding pixel ratio threshold value of the current scene, luminance threshold and each color channel histograms, determination is currently No is reversible-light shooting；

When determining currently is reversible-light shooting, the high dynamic of the current scene is obtained using high dynamic range images screening-mode Range image；

Wherein, the pixel ratio threshold value includes the first pixel ratio threshold value, the second pixel ratio threshold value, the luminance threshold packet It includes and corresponding first luminance threshold of the first pixel ratio threshold value, corresponding with the second pixel ratio threshold value second bright Spend threshold value；

It is described according to the corresponding pixel ratio threshold value of the current scene, luminance threshold and each color channel histograms, determination is worked as Whether preceding be reversible-light shooting, comprising:

Direction according to brightness from low to high and from high to low respectively successively counts pixel ratio in each color channel histograms The sum of example value；

Determine that each Color Channel is right respectively when reaching the first pixel ratio threshold value according to the sum of brightness pixel ratio from low to high Each first brightness value answered；

Determine that each Color Channel is right respectively when reaching the second pixel ratio threshold value according to the sum of brightness pixel ratio from high to low Each second brightness value answered；

If corresponding first brightness value of any Color Channel is less than the first luminance threshold, and the second brightness value is greater than the second luminance threshold Value, it is determined that be currently reversible-light shooting.

2. the method as described in claim 1, which is characterized in that the corresponding pixel ratio threshold value of the determination current scene And after luminance threshold, further includes:

Face datection is carried out to the current scene；

If it is determined that including human face region in the current scene, then the pixel ratio threshold value and the luminance threshold are adjusted It is whole.

3. method according to claim 2, which is characterized in that the pixel ratio threshold value include the first pixel ratio threshold value, Second pixel ratio threshold value, the luminance threshold include the first luminance threshold corresponding with the first pixel ratio threshold value, with Corresponding second luminance threshold of the second pixel ratio threshold value；It is described to the pixel ratio threshold value and the luminance threshold into Row adjustment, comprising:

Reduce the first pixel ratio threshold value, or increases by first luminance threshold；

Increase the second pixel ratio threshold value, or increases by second luminance threshold.

4. method a method according to any one of claims 1-3, which is characterized in that described to be obtained using high dynamic range images screening-mode Take the high dynamic range images of the current scene, comprising:

According to the corresponding each color channel histograms of the current scene, the corresponding exposure bias value of current scene is determined；

The corresponding normal exposure image of the current scene, under-exposure image and overexposure figure are obtained based on the exposure bias value Picture；

The normal exposure image, under-exposure image and overexposure light image are subjected to fusion treatment, generate the current scene High dynamic range images.

5. method a method according to any one of claims 1-3, which is characterized in that described to be believed according to the corresponding brightness of the current scene Breath, determines the corresponding pixel ratio threshold value of the current scene and luminance threshold, comprising:

According to the corresponding relationship of preset luminance threshold and brightness range, object brightness model corresponding with the current scene is determined It encloses；

According to preset brightness range and pixel ratio threshold value and the corresponding relationship of luminance threshold, the determining and object brightness model Enclose corresponding pixel ratio threshold value and luminance threshold.

6. a kind of high dynamic range image acquisition device characterized by comprising

First obtains module, for obtaining luminance information corresponding with current scene from automatic exposure control system；

First determining module, for determining the corresponding picture of the current scene according to the corresponding luminance information of the current scene Plain proportion threshold value and luminance threshold；

Second determining module, for determining the corresponding each color channel histograms of the current scene, wherein each Color Channel is straight Side's figure includes the corresponding relationship of the different brightness and pixel ratio under each Color Channel；

Third determining module, for according to the corresponding pixel ratio threshold value of the current scene, luminance threshold and each Color Channel Histogram determines whether as reversible-light shooting；

Second obtains module, for obtaining institute using high dynamic range images screening-mode when determining currently is reversible-light shooting State the high dynamic range images of current scene；

Wherein, the pixel ratio threshold value includes the first pixel ratio threshold value, the second pixel ratio threshold value, the luminance threshold packet It includes and corresponding first luminance threshold of the first pixel ratio threshold value, corresponding with the second pixel ratio threshold value second bright Spend threshold value；

The third determining module, comprising:

Statistic unit successively counts each Color Channel for the direction respectively according to brightness from low to high and from high to low The sum of pixel ratio in histogram；

First determination unit reaches the first pixel ratio threshold value according to the sum of brightness pixel ratio from low to high for determining When, corresponding each first brightness value of each Color Channel；

Second determination unit reaches the second pixel ratio threshold value according to the sum of brightness pixel ratio from high to low for determining When, corresponding each second brightness value of each Color Channel；

Third determination unit, if for corresponding first brightness value of any Color Channel less than the first luminance threshold, and second is bright Angle value is greater than the second luminance threshold, it is determined that is currently reversible-light shooting.

7. a kind of terminal device characterized by comprising memory, processor and camera module；

The camera module, for acquiring the image under current scene；

The memory, for storing executable program code；

The processor is run and the executable program for reading the executable program code stored in the memory The corresponding program of code, for realizing high-dynamic-range image acquisition method a method as claimed in any one of claims 1 to 5.

8. a kind of computer readable storage medium, is stored thereon with computer program, which is characterized in that the computer program is located Reason device realizes high-dynamic-range image acquisition method a method as claimed in any one of claims 1 to 5 when executing.

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