WO2020038074A1

WO2020038074A1 - Exposure control method and apparatus, and electronic device

Info

Publication number: WO2020038074A1
Application number: PCT/CN2019/090627
Authority: WO
Inventors: 张弓
Original assignee: Oppo广东移动通信有限公司
Priority date: 2018-08-22
Filing date: 2019-06-11
Publication date: 2020-02-27
Also published as: CN108900782A; CN108900782B

Abstract

Provided in the present disclosure are an exposure control method and apparatus, an electronic device, and a computer readable storage medium, the method comprising: by means of metering, determining a target exposure of each image frame to be acquired; on the basis of the target exposure of each image frame to be acquired and a preset light sensitivity of each image frame to be acquired, determining the exposure duration of each image frame to be acquired; if the exposure duration of at least one image frame to be acquired is less than a duration minimum, updating the exposure duration of the at least one image frame to be acquired on the basis of the duration minimum; and implementing exposure control on the basis of the exposure duration and light sensitivity of each image frame to be acquired. Thus, the dynamic range and overall brightness of night photography images are improved and the noise in the images is suppressed, and also ghost images and blur caused by hand shake are suppressed, improving the quality of night photography images and enhancing the user experience.

Description

Exposure control method, device and electronic equipment

Cross-reference to related applications

This disclosure claims the priority of China Patent Application No. “201810963320.5” filed by OPPO Guangdong Mobile Communication Co., Ltd. on August 22, 2018 with the invention name “Exposure Control Method, Device and Electronic Equipment”.

Technical field

The present disclosure relates to the field of imaging technology, and in particular, to an exposure control method, device, and electronic device.

Background technique

With the development of smart terminal technology, the use of mobile terminal equipment (such as smart phones, tablet computers, etc.) is becoming more and more popular. Most mobile terminal devices have built-in cameras, and with the enhancement of mobile terminal processing capabilities and the development of camera technology, the performance of built-in cameras is getting stronger and the quality of captured images is getting higher and higher. Today, mobile terminal devices are simple to operate and portable, and more and more users in daily life use mobile terminal devices such as smartphones and tablets to take pictures.

While smart mobile terminals bring convenience to people's daily photography, people's requirements for the quality of captured images are also getting higher and higher. However, due to the limitation of professional level, people do not know how to set appropriate shooting parameters according to the shooting scene.

Summary of the Invention

The present disclosure aims to solve at least one of the technical problems in the related art.

To this end, the present disclosure proposes an exposure control method, an apparatus electronic device, and a computer-readable storage medium to solve the related art, in a night scene scene where the shooting screen is bright, the dynamic range of the captured image and the surrounding area due to the measurement error. Low brightness, high noise level, technical issues that affect user experience.

An embodiment of one aspect of the present disclosure provides an exposure control method, including:

Metering to determine the target exposure for each frame of image to be acquired;

Determining the exposure duration of the images to be acquired in each frame according to the target exposure of the images to be acquired in each frame and the preset sensitivity of the images to be acquired in each frame;

If the exposure duration of at least one frame of the image to be collected is less than the lower limit of time, updating the exposure time of the at least one frame of the image to be collected according to the lower limit of time;

Perform exposure control according to the exposure duration and sensitivity of each frame of images to be acquired.

According to the exposure control method of the embodiment of the present disclosure, the target exposure amount of each frame to be acquired is determined by photometry; the target exposure amount of each frame to be acquired and the preset sensitivity of each frame to be acquired are used to determine each frame to be acquired. The exposure duration of the captured image. If the exposure duration of at least one frame of the to-be-collected image is less than the lower limit of time, the exposure duration of at least one frame of the to-be-acquired image is updated according to the lower limit of time, and finally, Exposure control. Therefore, the exposure duration of each frame to be acquired is determined according to the degree of jitter of the imaging device and the ambient light brightness of the current shooting scene, and then the exposure duration of at least one frame to be acquired is updated according to the lower limit of the duration, and finally based on the updated The exposure duration and sensitivity of each frame of images to be collected, and exposure control, and then imaging, not only improves the dynamic range and overall brightness of the captured image in the night scene shooting mode, effectively suppresses the noise in the captured image, and improves the night shot image. Quality and improved user experience.

An embodiment of another aspect of the present disclosure provides an exposure control device, including:

A light metering module, which is used for light metering to determine the target exposure of each frame of images to be acquired;

A determining module, configured to determine the exposure duration of the images to be acquired in each frame according to the target exposure of the images to be acquired in each frame and the preset sensitivity of the images to be acquired in each frame;

An update module configured to update the exposure duration of the at least one frame of images to be acquired if the exposure duration of the at least one frame of images to be acquired is less than the lower limit of time;

A control module is configured to perform exposure control according to the exposure duration and sensitivity of the images to be collected in each frame.

The exposure control device according to the embodiment of the present disclosure determines the target exposure amount of the images to be acquired by each frame through photometry; and determines the target exposure of each frame according to the target exposure amount of the images to be acquired in each frame and the preset sensitivity of the images to be acquired in each frame. The exposure duration of the captured image. If the exposure duration of at least one frame of the to-be-collected image is less than the lower limit of time, the exposure duration of at least one frame of the to-be-acquired image is updated according to the lower limit of time, and finally, Exposure control. Therefore, the exposure duration of each frame to be acquired is determined according to the degree of jitter of the imaging device and the ambient light brightness of the current shooting scene, and then the exposure duration of at least one frame to be acquired is updated according to the lower limit of the duration, and finally based on the updated The exposure duration and sensitivity of each frame of images to be collected, and exposure control, and then imaging, not only improves the dynamic range and overall brightness of the captured image in the night scene shooting mode, effectively suppresses the noise in the captured image, and improves the night shot image. Quality and improved user experience.

Embodiments of still another aspect of the present disclosure provide one or more non-volatile computer-readable storage media containing computer-executable instructions on which a computer program is stored, characterized in that the program is implemented as described above when executed by a processor. The exposure control method according to the embodiment.

An embodiment of another aspect of the present disclosure provides an electronic device including a memory and a processor. The memory stores computer-readable instructions. When the processor executes the program, the exposure according to the foregoing embodiment is implemented. Control Method.

Additional aspects and advantages of the present disclosure will be given in part in the following description, part of which will become apparent from the following description, or be learned through the practice of the present disclosure.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and / or additional aspects and advantages of the present disclosure will become apparent and easily understood from the following description of the embodiments in conjunction with the accompanying drawings, in which:

FIG. 1 is a schematic flowchart of an exposure control method according to an embodiment of the present disclosure;

2 is a schematic flowchart of determining a preset exposure compensation value of an image to be acquired in each frame according to an embodiment of the present disclosure;

3 is a schematic flowchart of another exposure control method according to an embodiment of the present disclosure;

4 is a schematic structural diagram of an exposure control apparatus according to an embodiment of the present disclosure;

5 is a schematic block diagram of an electronic device according to some embodiments of the present disclosure;

FIG. 6 is a schematic block diagram of an image processing circuit according to some embodiments of the present disclosure.

detailed description

Hereinafter, embodiments of the present disclosure will be described in detail. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the drawings are exemplary, and are intended to explain the present disclosure, and should not be construed as limiting the present disclosure.

Related technologies In night shooting scenes, due to poor lighting conditions, in order to improve the shooting quality, during the shooting process, people are accustomed to placing the subject in the middle of the frame, performing long exposure, medium exposure, and short exposure, and then different exposures The images obtained under the combined image are output for imaging to improve the imaging effect of the image. However, in this shooting mode, the dynamic range of the captured image is not wide enough, and the overall brightness of the image is relatively low. Noise may also be introduced during the shooting process.

The embodiments of the present disclosure are directed to the related art. When shooting an image in a night scene, the metering error occurs when the middle range of the shooting scene is bright, so that the dynamic range of the captured image and the brightness of the surrounding dark area are low, and the noise level is high. , A problem that affects user experience, and proposes an exposure control method.

According to the exposure control method provided in the embodiment of the present disclosure, the target exposure amount of the image to be collected is determined by metering; and each frame is determined according to the target exposure amount of the image to be collected and the preset sensitivity of the image to be collected. The exposure duration of the image to be collected, if the exposure duration of at least one frame of the image to be collected is less than the lower limit of time, the exposure time of at least one frame of the image to be collected is updated according to the lower limit of time, and finally according to the exposure time and sensitivity of the image to be collected of each frame, Perform exposure control.

Hereinafter, an exposure control method and apparatus according to embodiments of the present disclosure will be described with reference to the drawings.

FIG. 1 is a schematic flowchart of an exposure control method according to an embodiment of the present disclosure.

The exposure control method of the embodiment of the present disclosure is applied to an electronic device. The electronic device may be a hardware device such as a mobile phone, a tablet computer, a personal digital assistant, a wearable device, and other operating systems and imaging devices.

As shown in FIG. 1, the exposure control method includes the following steps:

In step 101, photometry is performed to determine a target exposure of each frame to be acquired.

The exposure amount refers to the amount of light received by the photosensitive device in the imaging device during the exposure time. The exposure amount is related to the aperture, the exposure time, and the sensitivity. Among them, the aperture is the aperture diameter, which determines the amount of light passing through in a unit time; the exposure time refers to the time that the light passes through the lens; the sensitivity, also known as the ISO value, is an index to measure the sensitivity of the film to light. In terms of the light-receiving speed of the light-sensitive device, the higher the ISO value, the stronger the light-receiving capacity of the light-sensitive component.

It should be noted that when the sensitivity of the imaging device is low, longer exposure time is required to achieve the same imaging effect as when the sensitivity is higher. The sensitivity of a digital camera is a kind of index similar to the sensitivity of a film. The ISO value of a digital camera can be adjusted by adjusting the sensitivity of the photosensitive device or combining the sensing points, that is, by increasing the light sensitivity of the photosensitive device. Or combine several adjacent photosensitive points to increase the ISO value. Of course, in order to reduce the exposure time, using a relatively high sensitivity usually introduces more noise, which will lead to a reduction in image quality. Therefore, in night scenes, in order to obtain better noise suppression effects, it is desirable to set a lower sensitivity, such as 100ISO or 200ISO, etc. At the same time, because the aperture of electronic devices such as mobile phones usually adopts a fixed value, it is necessary to increase the exposure time accordingly. , That is, the shutter time.

Specifically, the preview image of the current shooting scene is obtained by the imaging device, and the ambient light brightness of each area of the preview image is obtained by measuring by the photosensitive device, and then the reference exposure amount is determined according to the brightness information of the preview image. Where the aperture is fixed, the reference exposure amount may specifically include a reference exposure duration and a reference sensitivity.

In the embodiment of the present disclosure, the reference exposure amount refers to the brightness information of the current environment obtained by metering the preview image, and the exposure amount determined to be compatible with the brightness information of the current environment. The value of the reference exposure amount may be a reference Product of sensitivity and reference exposure time.

The reference sensitivity may be a sensitivity determined in accordance with the current degree of shake of the imaging device according to the current degree of shake, or a sensitivity obtained through photometry, which is not limited in this embodiment. It can be understood that, because the exposure amount and sensitivity affect the overall shooting time, and the shooting time is too long, it may cause the degree of shake of the imaging device to increase during handheld shooting, thereby affecting the image quality. Therefore, when determining the reference sensitivity according to the current shake level of the imaging device, the shooting duration should be controlled within a suitable range.

Specifically, since the exposure amount is related to the aperture, the exposure duration, and the sensitivity, when the size of the aperture is fixed, the reference exposure duration can be determined according to the reference exposure amount and the reference sensitivity. Taking the reference exposure time as EV0, the target exposure amount of the image to be acquired in each frame can be determined according to the preset exposure compensation value of the image to be acquired in each frame.

The preset exposure compensation value refers to an exposure value (Exposure Value, EV) set in advance according to the ambient light brightness of the current shooting scene. In the original definition of the exposure value, the exposure value does not refer to an accurate value, but refers to "the combination of all camera apertures and exposure time that can give a uniform exposure amount". Sensitivity, aperture, and exposure time determine the exposure of the camera. Different parameter combinations can produce equal exposure, that is, the EV values of these different combinations are the same. For example, if the sensitivity is the same, use 1/125. The combination of the exposure time in seconds and the aperture of f11 is the same as that obtained by using the combination of 1/250 second exposure time and f8 shutter, that is, the EV value is the same. When the EV value is 0, it means the exposure amount obtained when the sensitivity is 100, the aperture factor is f1, and the exposure duration is 1 second; the exposure amount is increased by one stop, that is, the exposure duration is doubled, or the sensitivity is doubled, or When the aperture is increased by one stop, the EV value is increased by 1, that is, the exposure amount corresponding to EV1 is twice the exposure amount corresponding to EV0.

As an example, if the imaging device determines that the reference exposure of each frame to be acquired is 400 according to the measured brightness information of the preview image, and the reference sensitivity ISO value is 100 at this time, the reference exposure duration is 4s. If the preset exposure compensation value of each frame to be acquired is EV + 1, it can be determined that the target exposure amount at this time is 800. Among them, EV + 1 exposure compensation refers to an increase in exposure relative to the exposure amount corresponding to the metering data of the imaging device, that is, the actual exposure amount is twice the exposure amount corresponding to the metering data.

In the embodiment of the present disclosure, when the exposure compensation value is preset, the EV value corresponding to the determined reference exposure amount can be preset to 0, and EV + 1 means to increase the exposure by one step, that is, the exposure amount is twice the reference exposure amount. , EV + 2 means to increase the exposure by two stops, that is, the exposure is 4 times the reference exposure, and EV-1 means to reduce the exposure by one stop, that is, the exposure is 0.5 times the reference exposure, and so on.

For example, if the number of images to be acquired is 7 frames, the corresponding preset exposure compensation value EV value may be [+ 1, + 1, + 1, + 1,0, -3, -6]. Among them, the frame with a preset exposure compensation value of EV + 1 can solve the problem of noise. Time-domain noise reduction is performed through the frame with a relatively high brightness, and the details in the dark part are improved while suppressing noise; the preset exposure compensation value is EV-6. Frames can solve the problem of highlight overexposure and preserve the details of highlight areas; frames with preset exposure compensation values of EV0 and EV-3 can be used to maintain the transition from highlights to dark areas and maintain better light and dark transitions Effect.

Step 102: Determine the exposure duration of the image to be acquired in each frame according to the target exposure of the image to be acquired in each frame and the preset sensitivity of the image to be acquired in each frame.

In an embodiment of the present disclosure, as a possible implementation manner, when the preset sensitivity of the image to be collected in each frame is the same, the preset sensitivity of the image to be collected in each frame may be determined according to the ambient light brightness of the shooting scene. When the shooting scene is relatively dark, increasing the sensitivity can make the shutter speed faster, thereby reducing picture shake.

As another possible implementation manner, when the preset sensitivity of the image to be collected in each frame is the same, the preset sensitivity of the image to be collected in each frame may be determined according to the degree of jitter.

Specifically, in order to determine the degree of shake, the displacement information may be collected according to a displacement sensor provided in the imaging device, and further, the degree of shake of the imaging device may be determined according to the collected displacement information of the imaging device. When the jitter level of the imaging device is greater than or equal to the jitter threshold, determine the preset sensitivity value of the image to be acquired in each frame in the current shooting scene as the first sensitivity value; when the jitter level of the imaging device is less than the jitter threshold, determine the current shooting The preset sensitivity value of the images to be collected in each frame of the scene is the second sensitivity value. The jitter threshold is a jitter value preset in the imaging device and used to determine a preset sensitivity value.

The first light sensitive value is greater than the second light sensitive value, the first light sensitive value is a preset multiple of the second light sensitive value, and the value of the preset multiple is greater than or equal to two. As a possible implementation manner, in order to obtain lower noise, the second sensitivity value may be the minimum sensitivity of the imaging device, that is, the value of the second sensitivity value is 100 ISO, and accordingly, the value range of the first sensitivity value is It can be 200, 400, 800 or higher.

Since the exposure amount is equal to the sensitivity times the exposure time, in the embodiment of the present disclosure, according to the target exposure amount of each frame to be acquired and the preset sensitivity of each frame to be acquired, the exposure of each frame to be acquired may be determined. duration.

As an example, if the target exposure of a frame to be acquired determined by metering is 800, the preset sensitivity of the determined image to be acquired for the frame is 400 ISO, and the exposure time for collecting the image of the frame is 2s. With this method, the exposure time of the images to be acquired in each frame can be determined.

In step 103, if the exposure duration of at least one frame of the image to be collected is shorter than the lower limit of time, the exposure time of at least one frame of the image to be collected is updated according to the lower limit of time.

The lower limit of the duration of the exposure duration is greater than or equal to 10 ms. Based on experiments, when the exposure time is less than 10ms, noise degradation will occur. At the same time, for some devices, the minimum exposure time that can be set is 10ms. Therefore, the lower limit of the duration is set to be greater than or equal to 10ms.

In the embodiment of the present disclosure, when the exposure duration of at least one frame of the image to be collected is less than the lower limit of the exposure time, at this time, the exposure duration of the at least one frame of the image to be collected is set to the lower limit of the time. Further, the sensitivity of the at least one frame of the to-be-acquired image is updated according to the target exposure amount and the lower limit of the duration of the image to be collected, and the relationship between the exposure amount and the sensitivity and the exposure time. Furthermore, according to the lower limit of the exposure time, the exposure time of the at least one frame of the image to be acquired is updated.

As an example, assuming that the lower limit of the exposure time is 10ms, the preset sensitivity of each frame to be captured is 100 ISO, the image to be collected is 4 frames, and the preset exposure compensation value EV value can be [-6, -5 , -4, 0]. If EV0 is 100ms and 100ISO, when the preset exposure compensation value is EV-6, the exposure time for capturing a frame of images to be captured is 1.5ms and the sensitivity is 100ISO. At this time, the exposure time of the frame image is 1.5ms less than the duration. If the lower limit is 10 ms, the exposure duration of the image to be collected in the frame is set to the lower limit of 10 ms, and the sensitivity of the image to be collected in the frame is set to 100 ISO. It can be seen that by updating the exposure time of the image to be collected in this frame, the image brightness is brightened. The target exposure of the frame is increased from 1.5ms × 100ISO to 10ms × 100ISO, and the target exposure is 20/3 times that before the update.

Further, in order to make the exposure transition of each frame natural, both the dark and bright areas can be better exposed, and the remaining frames can also be simultaneously brightened. Still referring to the foregoing example, for EV-6 image frames, the target exposure amount is 20/3 times before the update, and the target exposure amounts of the remaining frames are also synchronized to 20/3 times before the update. Specifically, this can be achieved by increasing the exposure duration or by increasing the ISO, which is not limited in this embodiment.

Step 104: Perform exposure control according to the exposure duration and sensitivity of the image to be collected in each frame.

In the embodiment of the present disclosure, the imaging device may perform exposure control according to the determined exposure duration and sensitivity of each frame to be acquired, and then perform imaging.

According to the exposure control method of the embodiment of the present disclosure, the target exposure amount of each frame to be acquired is determined by photometry; the target exposure amount of each frame to be acquired and the preset sensitivity of each frame to be acquired are used to determine each frame to be acquired. The exposure duration of the captured image. If the exposure duration of at least one frame of the to-be-collected image is less than the lower limit of time, the exposure duration of at least one frame of the to-be-acquired image is updated according to the lower limit of the duration, and finally based on the exposure time and sensitivity of each frame of the to-be-collected image, Exposure control. Therefore, the exposure duration of each frame to be acquired is determined according to the degree of jitter of the imaging device and the ambient light brightness of the current shooting scene, and then the exposure duration of at least one frame to be acquired is updated according to the lower limit of the duration, and finally based on the updated The exposure duration and sensitivity of each frame of images to be collected, exposure control, and then imaging, not only improves the dynamic range and overall brightness of the captured image in the night scene shooting mode, but also effectively suppresses noise in the captured image and improves the night scene captured image Quality and improved user experience.

As a possible implementation manner, in the embodiment of the present disclosure, before determining a target exposure amount of an image to be acquired for each frame according to a reference exposure amount and an exposure compensation value preset for each frame of an image to be acquired, first determine each frame to be acquired. The preset exposure compensation value of the image, as shown in Figure 2, can include the following steps:

Step 201: Obtain a preview picture.

In the embodiment of the present disclosure, a preview screen of a current shooting scene may be obtained through an imaging device, and is used to determine whether the current shooting scene belongs to a night scene.

Step 202: According to the picture content of the preview picture, determine that the current shooting scene belongs to a night scene.

Specifically, due to different ambient brightness values in different scenes, the contents of the preview screen are also different. Based on the screen contents of the preview scene of the current shooting scene and the ambient brightness values of each area, it is determined whether the current shooting scene belongs to a night scene.

For example, if the picture content of the preview screen includes the night sky or night light sources, or the ambient brightness values in each area of the preview screen match the brightness distribution characteristics of the image under the night environment, it can be determined that the current shooting scene belongs to the night scene.

Step 203: Identify a night scene mode applicable to the current shooting scene according to the degree of jitter of the imaging device and / or whether the preview screen contains a human face.

In the embodiment of the present disclosure, the displacement information provided by the imaging device may be acquired through a displacement sensor provided by the imaging device, and then the current jitter degree of the imaging device may be determined according to the obtained displacement information. Therefore, it can be judged by the degree of shaking of the imaging device whether the user fixes the imaging device on a tripod for shooting or shoots in a handheld mode. Furthermore, according to the current jitter level of the imaging device, a night scene mode applicable to the current shooting scene is identified.

As an example, the current degree of jitter of the imaging device may be determined by acquiring current Gyro-sensor information of the electronic device.

Among them, the gyroscope is also called angular velocity sensor, which can measure the rotational angular velocity when the physical quantity is deflected and tilted. In the imaging equipment, the gyroscope can measure the movement of rotation and deflection very well, so that it can accurately analyze and judge the actual movement of the user. The gyroscope information (gyro information) of the electronic device may include the motion information of the imaging device in three dimensions in the three-dimensional space, and the three dimensions of the three-dimensional space may be expressed as the three directions of the X-axis, Y-axis, and Z-axis, respectively. , X-axis, Y-axis, and Z-axis are perpendicular to each other.

Therefore, in the embodiment of the present disclosure, the current jitter degree of the imaging device can be determined according to the current gyro information of the electronic device. The greater the absolute value of the gyro movement of the electronic device in the three directions, the greater the degree of jitter of the imaging device. Specifically, the absolute value threshold of the gyro motion in the three directions can be preset, and the relationship between the absolute value of the currently acquired gyro motion in the three directions and the preset threshold is used to determine the imaging device's The current degree of jitter.

For example, suppose the preset thresholds are the first threshold A, the second threshold B, and the third threshold C, and A <B <C. The sum of the absolute values of the gyro motion in the three directions currently obtained is S . If S <A, then determine the current jitter of the imaging device as “no jitter”; if A <S <B, you can determine the current jitter of the imaging device as “slight jitter”; if B <S <C, you can It is determined that the current jitter level of the imaging device is "small jitter"; if S> C, it can be determined that the current jitter level of the imaging device is "large jitter".

It should be noted that the above examples are merely exemplary and cannot be regarded as limiting the present disclosure. In actual use, the number of thresholds and specific values of each threshold can be preset according to actual needs, and the mapping relationship between the gyro information and the degree of jitter of the imaging device can be preset according to the relationship between the gyro information and each threshold.

As another possible implementation manner, the night view mode applicable to the current shooting scene may be identified by determining that the preview screen of the imaging device is sufficient to include a human face.

In the embodiment of the present disclosure, whether the preview picture includes a human face can be determined by using a face recognition technology. Face recognition technology is to identify the identity by analyzing and comparing the visual characteristic information of the face. It belongs to the biometric recognition technology, which distinguishes the individual organisms from the biological characteristics of the organisms (generally specifically people). At present, face recognition technology has been applied in many fields, such as digital camera face autofocus and smile shutter technology; corporate and residential security and management; access control systems; camera surveillance systems, etc. Commonly used face recognition algorithms include: Feature-based recognition algorithms (Feature-based recognition algorithms), Appearance-based recognition algorithms (Template-based recognition algorithms) recognition algorithms), algorithms using neural networks for recognition (Recognition algorithms, neural networks), and so on.

It should be noted that when it is detected that the preview image contains a human face, the metering module of the imaging device automatically performs metering mainly on the human face area, and determines the reference exposure amount according to the photometric result of the human face area. However, in night scenes, the light intensity of the face area is usually low, which results in a determined reference exposure amount that is higher than the reference exposure amount determined when the face is not included. Overexposed frames easily lead to overexposure of the human face area, resulting in poor imaging results of the collected images. Therefore, for the same degree of jitter, compared with the case where the face is included in the preview picture, the night scene mode is different.

Step 204: Determine a preset exposure compensation value for each frame of the image to be acquired according to the night scene mode.

As a possible implementation manner, the degree of jitter of the imaging device is different, and the night scene mode applicable to the current shooting scene is also different. Therefore, the preset exposure compensation value of the image to be acquired determined for each frame is also different. In the embodiment of the present disclosure, the mapping relationship between the degree of jitter of the imaging device and the exposure compensation value may be preset to determine the preset exposure compensation value of the image to be acquired in each frame currently based on the degree of jitter of the imaging device.

For example, when the degree of jitter of the imaging device is "no jitter", the range of EV values of the exposure compensation values corresponding to the images to be acquired in each frame is preset to -6 to 2, and the difference between adjacent EV values Is 0.5; the jitter level of the imaging device is "slight jitter", the EV value range of the exposure compensation value corresponding to each frame of the image to be acquired is preset to -5 to 1, and the difference between adjacent EV values is 1, wait.

As another possible implementation form, it is detected whether the preview screen of the imaging device includes a human face. When the preview screen contains a human face and does not include a human face, the night scene mode applicable to the current shooting scene is different. The exposure compensation value preset for the captured image is also different.

As another possible implementation manner, for the same degree of jitter, different exposure compensation values can be determined for each frame of images to be acquired according to whether a preview picture includes a human face. Therefore, for the same degree of jitter, it can correspond to multiple exposure compensation values. For example, the degree of dithering of the imaging device is "slightly dithered", and the preset exposure compensation value of each frame of the image to be collected includes two cases, including a human face and a non-human face.

In the night scene mode, when a face is included in the image to be collected, the light intensity of the face area is usually low, which results in a determined reference exposure amount that is higher than the reference exposure amount determined when the face is not included. When too many overexposure frames are still collected when a human face is included, it will easily lead to overexposure of the face area, resulting in poor imaging of the captured image. The corresponding exposure compensation mode needs to have a lower exposure compensation range. Therefore, for the same degree of jitter, compared with the case where the face is included in the preview screen compared to when no face is included, after determining the current degree of jitter of the imaging device and whether the preview screen contains a face, it can be determined from the current actual situation. The preset exposure compensation value matches the situation.

According to the exposure control method of the embodiment of the present disclosure, by acquiring a preview screen, it is determined that the current shooting scene belongs to a night scene according to the screen content of the preview screen, and according to the degree of jitter of the imaging device and / or whether the preview screen contains a human face, it is identified that the current shooting scene is applicable. Night scene mode, and further, according to the night scene mode, determine a preset exposure compensation value for each frame of images to be acquired. Therefore, according to the degree of jitter of the imaging device and / or whether the preview screen contains a human face, a night scene mode in the shooting scene is determined, and then a preset exposure compensation value for each frame to be acquired is determined, which is further used to determine each frame to be The exposure time of the captured image is updated according to the lower limit of the duration of at least one frame of the image to be collected. Finally, the exposure is controlled based on the exposure time and sensitivity of the updated image of each frame to be collected, and then imaging is performed, which not only improves the night scene shooting mode Lower the dynamic range and overall brightness of the captured image, and effectively suppress the noise in the captured image, improve the quality of the night scene captured image, and improve the user experience.

In order to clearly explain the previous embodiment, this embodiment provides another exposure control method. FIG. 3 is a schematic flowchart of another exposure control method according to an embodiment of the present disclosure.

As shown in FIG. 3, the exposure control method may include the following steps:

In step 301, photometry is performed to determine a target exposure of the image to be acquired in each frame.

Step 302: Determine the exposure duration of the image to be acquired in each frame according to the target exposure of the image to be acquired in each frame and the preset sensitivity of the image to be acquired in each frame.

In step 303, if the exposure duration of at least one frame of the image to be collected is less than the lower limit of time, the exposure time of at least one frame of the image to be collected is updated according to the lower limit of time.

In the embodiment of the present disclosure, the specific implementation processes and principles of the above steps 301-303 are as described in steps 101-103 in the foregoing embodiment, and details are not described herein again.

Step 304: Update the sensitivity of the image to be acquired whose exposure duration is greater than the upper limit of the duration; and update the exposure duration of the image to be acquired whose exposure duration is greater than the upper limit of the duration according to the corresponding target exposure amount and the upper limit of the duration.

The upper limit of the exposure duration is a preset exposure duration value.

Specifically, for an image to be acquired whose exposure time is longer than the upper limit of the duration, the exposure time of the image to be acquired is set to the upper limit of the duration. Since the exposure amount is the product of the sensitivity and the exposure time, the corresponding target exposure amount and the upper limit of the duration , Update the sensitivity of the image to be acquired as the ratio between the target exposure and the upper limit of the duration.

It should be noted that when the exposure time of the image to be collected is greater than the upper limit, if the exposure time is used for exposure, the exposure time is too long, which will cause screen jitter. Therefore, the exposure time of the image to be collected whose exposure time is longer than the upper limit is updated to Maximum duration.

Step 305: For the remaining frames of images to be acquired whose exposure time is greater than or equal to the lower limit of time, the sensitivity of the remaining frames of images to be acquired is updated according to the ratio.

Specifically, for the remaining frames of images to be acquired whose exposure time is greater than or equal to the lower limit of time, first determine the ratio between the updated exposure time of the to-be-collected images that is less than the lower limit of time and the exposure time before the update, and then compare the ratio with the rest The product of the sensitivity or exposure time before updating of the images to be acquired in each frame is used as the sensitivity or exposure time after updating of the images to be acquired in the remaining frames.

As an example, if the exposure time is greater than or equal to the lower limit of the duration of the image to be captured is 4 frames, it is determined that the preset sensitivity value of each frame is 100 ISO according to the degree of jitter of the imaging device, and the exposure durations of the 4 frames of image to be captured are respectively 100ms, 200ms, 400ms, and 800ms. Considering that the ratio between the updated exposure time of the to-be-collected image and the exposure time before the update is less than the lower limit of the time length, the value is 10ms / 1.5ms, that is, 20/3. Therefore, it is determined that the exposure time of the four frames to be collected is expanded to the original 20/3 times of 100ms, 200ms, 400ms and 800ms.

The method for updating the sensitivity is similar to the method for updating the exposure duration. It is only necessary to replace the exposure duration with the sensitivity, but it should be noted that the exposure duration and update can only be updated according to the aforementioned to-be-collected images that are less than the lower limit of the duration. One of the ratio between the previous exposure time and the exposure time and the sensitivity is updated. If the exposure time and the sensitivity need to be updated at the same time, the ratio needs to be assigned according to the weight and then updated. For example, the exposure duration and the sensitivity are each half weighted. If the ratio between the updated exposure duration of the to-be-collected image smaller than the lower duration and the exposure duration before the update is R, the exposure duration is enlarged to the original R / 2 To increase the sensitivity to the original R / 2 times.

Step 306: Perform exposure control according to the exposure duration and sensitivity of the images to be collected in each frame.

According to the exposure control method of the embodiment of the present disclosure, the target exposure amount of each frame to be acquired is determined by photometry; the target exposure amount of each frame to be acquired and the preset sensitivity of each frame to be acquired are used to determine each frame to be acquired. The exposure duration of the captured image. If the exposure duration of at least one frame of the to-be-acquired image is less than the lower duration limit, the exposure duration of at least one frame of the to-be-acquired image is updated according to the lower duration limit; for the to-be-acquired image whose exposure duration is greater than the upper duration limit, the corresponding target The exposure amount and the upper limit of the duration are used to update the sensitivity; and according to the upper limit of the duration, the exposure time of the image to be collected whose exposure time is greater than the upper limit of the duration is updated, and finally exposure control is performed according to the exposure time and sensitivity of the image to be collected for each frame. Therefore, the exposure duration of each frame to be captured is determined according to the degree of jitter of the imaging device and the ambient light brightness of the current shooting scene, and then the sensitivity of each frame to be collected is updated according to the lower limit of exposure duration and the upper limit of duration. The updated exposure time and sensitivity of each frame to be captured after the update, and exposure control, and then imaging, not only improves the dynamic range and overall brightness of the captured image in the night shooting mode, but also effectively suppresses noise in the captured image and improves The quality of night shot images improves the user experience.

In order to implement the above embodiments, the present disclosure also proposes an exposure control device.

FIG. 4 is a schematic structural diagram of an exposure control apparatus according to an embodiment of the present disclosure.

As shown in FIG. 4, the exposure control device 100 includes a photometric module 110, a determination module 120, an update module 130, and a control module 140.

The photometry module 110 is configured to perform photometry to determine a target exposure amount of an image to be acquired in each frame.

The determining module 120 is configured to determine an exposure duration of the image to be acquired in each frame according to a target exposure amount of the image to be acquired in each frame and a preset sensitivity of the image to be acquired in each frame.

The update module 130 is configured to update the exposure duration of at least one frame of the image to be acquired if the exposure time of the at least one frame of image to be acquired is less than the lower limit of time. The lower limit of the duration is greater than or equal to 10 ms.

The control module 140 is configured to perform exposure control according to the exposure duration and sensitivity of the image to be collected in each frame.

As another possible implementation manner, the exposure control apparatus 100 further includes:

The first determining module is configured to determine the preset sensitivity of the image to be collected for each frame according to the degree of jitter.

As another possible implementation manner, the first determining module may also be specifically used for

Obtain the collected displacement information from the sensors set by the imaging equipment;

Determine the degree of jitter of the imaging device according to the displacement information;

If the degree of shaking is greater than or equal to the shaking threshold, determining that the preset sensitivity value is the first sensitivity value;

If the dithering degree is less than the dithering threshold, it is determined that the preset sensitivity value is the second sensitivity value, wherein the first sensitivity value is greater than the second sensitivity value.

The first photosensitivity value is a preset multiple of the second photosensitivity value, and the preset multiplier value is greater than or equal to 2; the second photosensitivity value is the minimum sensitivity of the imaging device.

As another possible implementation manner, the photometric module 110 may also be specifically used for:

Determine the reference exposure amount according to the brightness information of the preview image; the reference exposure amount includes the reference exposure duration and the reference sensitivity;

The target exposure amount of the image to be acquired for each frame is determined according to the reference exposure amount and the preset exposure compensation value of the image to be acquired for each frame.

As another possible implementation manner, the photometric module 110 further includes:

An obtaining unit for obtaining a preview picture.

The first determining unit is configured to determine that the current shooting scene belongs to a night scene according to the picture content of the preview picture.

The identification unit is configured to identify a night scene mode applicable to the current shooting scene according to the degree of jitter of the imaging device and / or whether the preview screen contains a human face.

The second determining unit is configured to determine a preset exposure compensation value of the image to be acquired in each frame according to the night scene mode.

The second determining module is configured to determine a ratio between an updated exposure time of the at least one frame of the image to be acquired and an updated exposure time before the update.

The first update module is configured to update the sensitivity or exposure duration of the remaining frames of images to be acquired based on the ratio of the remaining frames of images to be collected whose exposure time is greater than or equal to the lower limit of the duration.

As another possible implementation manner, the first update module is further configured to:

The product of the ratio and the sensitivity of the remaining frames to be acquired before being updated is used as the sensitivity of the remaining frames to be acquired after being updated.

Alternatively, the product of the ratio and the exposure time before the images to be acquired in the remaining frames are updated is used as the exposure time after the images in the remaining frames are to be updated.

A second update module, configured to update the sensitivity of an image to be acquired whose exposure time is longer than the upper limit of the duration according to the corresponding target exposure amount and upper limit of the duration; and

According to the upper limit of the duration, the exposure duration of the image to be acquired whose exposure duration is greater than the upper limit of the duration is updated.

The exposure control device according to the embodiment of the present disclosure determines the target exposure amount of the images to be acquired by each frame through photometry; and determines the target exposure of each frame according to the target exposure amount of the images to be acquired in each frame and the preset sensitivity of the images to be acquired in each frame. The exposure duration of the captured image. If the exposure duration of at least one frame of the to-be-collected image is less than the lower limit of time, the exposure duration of at least one frame of the to-be-acquired image is updated according to the lower limit of time, and finally, Exposure control. Therefore, the exposure duration of each frame to be acquired is determined according to the degree of jitter of the imaging device and the ambient light brightness of the current shooting scene, and then the exposure duration of at least one frame to be acquired is updated according to the lower limit of the duration, and finally based on the updated The exposure duration and sensitivity of each frame of images to be collected, exposure control, and then imaging, not only improves the dynamic range and overall brightness of the captured image in the night scene shooting mode, but also effectively suppresses noise in the captured image and improves the night scene captured image Quality and improved user experience.

It should be noted that the foregoing explanation of the embodiment of the exposure control method is also applicable to the exposure control device of this embodiment, and details are not described herein again.

In order to implement the foregoing embodiments, an embodiment of the present disclosure further provides a computer-readable storage medium. One or more non-volatile computer-readable storage media containing computer-executable instructions, when the computer-executable instructions are executed by one or more processors, cause the processors to perform the following steps:

If the exposure duration of at least one frame of the image to be acquired is less than the lower limit of time, updating the sensitivity of the at least one frame of the image to be acquired according to the target exposure of the at least one frame of the image to be acquired and the lower limit of time; Lower limit of duration, updating the exposure duration of the at least one frame of images to be acquired;

In order to implement the above embodiments, the present disclosure also proposes an electronic device including a memory, a processor, and a computer program stored on the memory and executable on the processor. When the processor executes the program, the implementation is as described above. The exposure control method according to the embodiment.

Referring to FIG. 5, the present disclosure also provides another electronic device 200. The electronic device 200 includes a memory 50 and a processor 60. The memory 50 stores computer-readable instructions. When the computer-readable instructions are executed by the memory 50, the processor 60 is caused to execute the exposure control method according to any one of the foregoing embodiments.

FIG. 5 is a schematic diagram of the internal structure of the electronic device 200 in an embodiment. The electronic device 200 includes a processor 60, a memory 50 (for example, a non-volatile storage medium), an internal memory 82, a display screen 83, and an input device 84 connected through a system bus 81. The memory 50 of the electronic device 200 stores an operating system and computer-readable instructions. The computer-readable instructions can be executed by the processor 60 to implement the exposure control method of the embodiment of the present disclosure. The processor 60 is used to provide computing and control capabilities to support the operation of the entire electronic device 200. The internal memory 50 of the electronic device 200 provides an environment for execution of computer-readable instructions in the memory 52. The display screen 83 of the electronic device 200 may be a liquid crystal display or an electronic ink display, and the input device 84 may be a touch layer covered on the display screen 83, or may be a button, a trackball or a touch button provided on the housing of the electronic device 200 Board, which can also be an external keyboard, trackpad, or mouse. The electronic device 200 may be a mobile phone, a tablet computer, a notebook computer, a personal digital assistant, or a wearable device (for example, a smart bracelet, a smart watch, a smart helmet, or smart glasses). Those skilled in the art can understand that the structure shown in FIG. 5 is only a schematic diagram of a part of the structure related to the solution of the present disclosure, and does not constitute a limitation on the electronic device 200 to which the solution of the present disclosure is applied. The specific electronic device 200 may include more or fewer components than shown in the figure, or some components may be combined, or have different component arrangements.

Please refer to FIG. 6. The electronic device 200 according to the embodiment of the present disclosure includes an image processing circuit 90. The image processing circuit 90 may be implemented by using hardware and / or software components, including various types of ISP (Image Signal Processing) pipelines. Processing unit. FIG. 6 is a schematic diagram of an image processing circuit 90 in one embodiment. As shown in FIG. 6, for convenience of explanation, only various aspects of the image processing technology related to the embodiments of the present disclosure are shown.

As shown in FIG. 6, the image processing circuit 90 includes an ISP processor 91 (the ISP processor 91 may be the processor 60) and a control logic 92. The image data captured by the camera 93 is first processed by the ISP processor 91. The ISP processor 91 analyzes the image data to capture image statistical information that can be used to determine one or more control parameters of the camera 93. The camera 93 may include one or more lenses 932 and an image sensor 934. The image sensor 934 may include a color filter array (such as a Bayer filter). The image sensor 934 may obtain light intensity and wavelength information captured by each imaging pixel, and provide a set of raw image data that can be processed by the ISP processor 91. The sensor 94 (such as a gyroscope) may provide parameters (such as image stabilization parameters) of the acquired image processing to the ISP processor 91 based on the interface type of the sensor 94. The sensor 94 interface may be a SMIA (Standard Mobile Imaging Architecture) interface, other serial or parallel camera interfaces, or a combination of the foregoing interfaces.

In addition, the image sensor 934 may also send the original image data to the sensor 94. The sensor 94 may provide the original image data to the ISP processor 91 based on the interface type of the sensor 94, or the sensor 94 stores the original image data into the image memory 95.

The ISP processor 91 processes the original image data pixel by pixel in a variety of formats. For example, each image pixel may have a bit depth of 8, 10, 12, or 14 bits, and the ISP processor 91 may perform one or more image processing operations on the original image data and collect statistical information about the image data. The image processing operations may be performed with the same or different bit depth accuracy.

The ISP processor 91 may also receive image data from the image memory 95. For example, the sensor 94 interface sends the original image data to the image memory 95, and the original image data in the image memory 95 is then provided to the ISP processor 91 for processing. The image memory 95 may be an independent dedicated memory in the memory 50, a part of the memory 50, a storage device, or an electronic device, and may include a DMA (Direct Memory Access) feature.

When receiving raw image data from the image sensor 934 interface or from the sensor 94 interface or from the image memory 95, the ISP processor 91 may perform one or more image processing operations, such as time-domain filtering. The processed image data can be sent to the image memory 95 for further processing before being displayed. The ISP processor 91 receives processing data from the image memory 95, and performs processing on the image data in the original domain and in the RGB and YCbCr color spaces. The image data processed by the ISP processor 91 may be output to a display 97 (the display 97 may include a display screen 83) for viewing by a user and / or further processing by a graphics engine or a GPU (Graphics Processing Unit). In addition, the output of the ISP processor 91 can also be sent to the image memory 95, and the display 97 can read image data from the image memory 95. In one embodiment, the image memory 95 may be configured to implement one or more frame buffers. In addition, the output of the ISP processor 91 may be sent to an encoder / decoder 96 to encode / decode image data. The encoded image data can be saved and decompressed before being displayed on the display 97 device. The encoder / decoder 96 may be implemented by a CPU or a GPU or a coprocessor.

The statistical data determined by the ISP processor 91 may be sent to the control logic unit 92. For example, the statistical data may include image sensor 934 statistical information such as auto exposure, auto white balance, auto focus, flicker detection, black level compensation, and lens 932 shading correction. The control logic 92 may include a processing element and / or a microcontroller that executes one or more routines (such as firmware). The one or more routines may determine the control parameters of the camera 93 and the ISP processor according to the received statistical data. 91 control parameters. For example, the control parameters of the camera 93 may include sensor 94 control parameters (such as gain, integration time for exposure control, anti-shake parameters, etc.), camera flash control parameters, lens 932 control parameters (such as focus distance for focusing or zooming), or these parameters The combination. The ISP control parameters may include gain levels and color correction matrices for automatic white balance and color adjustment (eg, during RGB processing), and lens 932 shading correction parameters.

The following are the steps to implement the exposure control method using the image processing technology in FIG. 6:

Metering to determine the target exposure of each frame to be acquired; based on the target exposure of each frame to be acquired and the preset sensitivity of each frame to be acquired, determine the exposure time of each frame to be acquired; if at least one frame The exposure duration of the image to be acquired is less than the lower limit of time, and the sensitivity of the at least one frame of the image to be acquired is updated according to the target exposure of the at least one frame of image to be acquired and the lower limit of time, and according to the lower limit of time, the update is performed. The exposure duration of the at least one frame of images to be acquired; and performing exposure control according to the exposure duration and sensitivity of each frame of images to be acquired.

A person of ordinary skill in the art can understand that all or part of the processes in the methods of the foregoing embodiments can be implemented by using a computer program to instruct related hardware. The program can be stored in a non-volatile computer-readable storage medium. When the program is executed, it may include the processes of the embodiments of the methods described above. The storage medium may be a magnetic disk, an optical disk, a read-only memory (ROM), or the like.

The above-mentioned embodiments only express several implementation manners of the present invention, and their descriptions are more specific and detailed, but they cannot be understood as limiting the scope of the patent of the present invention. It should be noted that, for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can be made, which all belong to the protection scope of the present invention. Therefore, the protection scope of the invention patent shall be subject to the appended claims.

Claims

An exposure control method, characterized in that the method includes the following steps:

Metering to determine the target exposure for each frame of image to be acquired;

Determining the exposure duration of the images to be acquired in each frame according to the target exposure of the images to be acquired in each frame and the preset sensitivity of the images to be acquired in each frame;

If the exposure duration of at least one frame of the image to be collected is less than the lower limit of time, updating the exposure time of the at least one frame of the image to be collected according to the lower limit of time;

Perform exposure control according to the exposure duration and sensitivity of each frame of images to be acquired.
The exposure control method according to claim 1, wherein before determining the exposure duration of the images to be acquired in each frame according to the target exposure amount of the images to be acquired in each frame and the preset sensitivity of the images to be acquired in each frame, Also includes:

According to the degree of jitter, the preset sensitivity of the image to be collected for each frame is determined.
The exposure control method according to claim 2, wherein the preset sensitivity of the image to be collected in each frame is the same, and the determining the preset sensitivity of the image to be collected in each frame according to the degree of jitter comprises: :

Obtain the collected displacement information from the sensors set by the imaging equipment;

Determining a degree of jitter of the imaging device according to the displacement information;

If the degree of shaking is greater than or equal to a shaking threshold, determining that the preset sensitivity value is a first sensitivity value;

If the degree of dithering is less than the dithering threshold, it is determined that the preset sensitivity value is a second sensitivity value; wherein the first sensitivity value is greater than the second sensitivity value.
The exposure control method according to claim 3, wherein

The first photosensitive value is a preset multiple of the second photosensitive value, and the preset multiple takes a value greater than or equal to 2;

The second sensitivity value is a minimum sensitivity of the imaging device.
The exposure control method according to any one of claims 1 to 4, wherein:

The lower limit of the duration is greater than or equal to 10 ms.
The exposure control method according to any one of claims 1 to 5, wherein the metering to determine a target exposure amount of an image to be acquired in each frame comprises:

Determining a reference exposure amount according to the brightness information of the preview image; the reference exposure amount includes a reference exposure duration and a reference sensitivity;

The target exposure amount of the image to be acquired for each frame is determined according to the reference exposure amount and the preset exposure compensation value of the image to be acquired for each frame.
The exposure control method according to claim 6, wherein before determining the target exposure amount of the image to be acquired for each frame according to the reference exposure amount and an exposure compensation value preset for each frame of the image to be acquired, further comprising: :

Get preview picture;

Determine that the current shooting scene belongs to a night scene according to the picture content of the preview picture;

Identifying the night scene mode applicable to the current shooting scene according to the degree of shaking of the imaging device and / or whether the preview picture contains a human face;

According to the night scene mode, a preset exposure compensation value of each frame to be acquired is determined.
The exposure control method according to any one of claims 1-5, wherein after updating the exposure duration of the at least one frame of the image to be acquired according to the lower limit of duration, further comprising:

Determining a ratio between an updated exposure time of the at least one frame of images to be acquired and an exposure time before the update;

For the remaining frames of images to be acquired whose exposure time is greater than or equal to the lower limit of the time length, the sensitivity or exposure time of the images of the remaining frames to be acquired is updated according to the ratio.
The exposure control method according to claim 8, wherein updating the sensitivity or exposure duration of the images to be acquired in the remaining frames according to the ratio comprises:

Multiplying the ratio by the sensitivity of the remaining frames to be acquired before the image is updated as the sensitivity of the remaining frames to be acquired after the image is updated;

Alternatively, the product of the ratio and the exposure duration before the images to be acquired in the remaining frames are updated is used as the exposure duration after the images in the remaining frames are to be updated.
The exposure control method according to claim 8 or 9, wherein the pair of remaining frames to be acquired whose exposure duration is greater than or equal to the lower limit of the duration is updated according to the ratio, and the remaining frames to be acquired are updated Before the sensitivity of the image, it also includes:

Update the sensitivity of an image to be acquired whose exposure time is longer than the upper limit of time, according to the corresponding target exposure amount and the upper limit of time; and

Update the exposure duration of the image to be acquired whose exposure duration is greater than the duration upper limit according to the duration upper limit.
An exposure control device, characterized in that the device includes:

A light metering module, which is used for light metering to determine the target exposure of each frame of images to be acquired;

A determining module, configured to determine the exposure duration of the images to be acquired in each frame according to the target exposure of the images to be acquired in each frame and the preset sensitivity of the images to be acquired in each frame;

An update module for updating the sensitivity of the at least one frame of images to be acquired if the exposure time of the at least one frame of images to be acquired is less than the lower limit of time; And updating the exposure duration of the at least one frame of images to be acquired according to the lower duration limit;

A control module is configured to perform exposure control according to the exposure duration and sensitivity of the images to be collected in each frame.
The exposure control device according to claim 11, wherein the device further comprises:

The first determining module is configured to determine the preset sensitivity of the image to be collected for each frame according to the degree of jitter.
The exposure control device according to claim 12, wherein the first determining module is configured to:

Obtain the collected displacement information from the sensors set by the imaging equipment;

Determining a degree of jitter of the imaging device according to the displacement information;

If the degree of shaking is greater than or equal to a shaking threshold, determining that the preset sensitivity value is a first sensitivity value;

If the degree of dithering is less than the dithering threshold, it is determined that the preset sensitivity value is a second sensitivity value; wherein the first sensitivity value is greater than the second sensitivity value.
The exposure control device according to claim 13, wherein:

The first photosensitive value is a preset multiple of the second photosensitive value, and the preset multiple takes a value greater than or equal to 2;

The second sensitivity value is a minimum sensitivity of the imaging device.
The exposure control device according to any one of claims 11 to 14, wherein:

The lower limit of the duration is greater than or equal to 10 ms.
The exposure control device according to any one of claims 11-15, wherein the photometric module is configured to:

Determining a reference exposure amount according to the brightness information of the preview image; the reference exposure amount includes a reference exposure duration and a reference sensitivity;

The target exposure amount of the image to be acquired for each frame is determined according to the reference exposure amount and the preset exposure compensation value of the image to be acquired for each frame.
The exposure control device according to claim 16, wherein the photometry module further comprises:

An obtaining unit for obtaining a preview picture;

A first determining unit, configured to determine that a current shooting scene belongs to a night scene according to the picture content of the preview picture;

A recognition unit, configured to identify a night scene mode applicable to the current shooting scene according to the degree of jitter of the imaging device and / or whether the preview picture includes a human face;

The second determining unit is configured to determine a preset exposure compensation value of the image to be acquired in each frame according to the night scene mode.
The exposure control device according to any one of claims 11-15, wherein the exposure control device further comprises:

A second determining module, configured to determine a ratio between an updated exposure time of the at least one frame of the image to be acquired and an updated exposure time before the update;

A first updating module is configured to update the sensitivity or exposure duration of the remaining frames of images to be acquired according to the ratio for the remaining frames of images to be acquired whose exposure time is greater than or equal to the lower limit of the duration.
The exposure control device according to claim 18, wherein the first update module is configured to:

Multiplying the ratio by the sensitivity of the remaining frames to be acquired before the image is updated as the sensitivity of the remaining frames to be acquired after the image is updated;

Alternatively, the product of the ratio and the exposure duration before the images to be acquired in the remaining frames are updated is used as the exposure duration after the images in the remaining frames are to be updated.
The exposure control device according to claim 18 or 19, wherein the exposure control device further comprises:

A second update module, configured to update the sensitivity of an image to be acquired whose exposure duration is greater than the duration upper limit according to the corresponding target exposure amount and the duration upper limit; and

Update the exposure duration of the image to be acquired whose exposure duration is greater than the duration upper limit according to the duration upper limit.
One or more non-transitory computer-readable storage media containing computer-executable instructions, when said computer-executable instructions are executed by one or more processors, causing said processors to execute the instructions in claims 1-10 The exposure control method according to any one.
An electronic device includes a memory and a processor. The memory stores computer-readable instructions. When the instructions are executed by the processor, the processor causes the processor to execute the instructions as claimed in any one of claims 1-10. The exposure control method described above.