CN107948538A - Imaging method, device, mobile terminal and storage medium - Google Patents

Abstract

A kind of imaging method of disclosure, device, mobile terminal and storage medium, wherein, method includes：When picture of finding a view belongs to target scene, identify in picture of finding a view and whether include portrait, wherein, the background of target scene is in dim light state, if including portrait in picture of finding a view, the sensitivity ISO of camera is turned down, and opens flash lamp and light filling is carried out to portrait, in the state of flash lamp unlatching, picture of finding a view is shot using the camera.When being shot under background is in the target scene of dim light state to personage, background luminance is forced down by the sensitivity ISO for turning down camera, light filling is carried out to portrait by opening flash lamp, it is achieved thereby that background luminance is forced down at the same time and lifts the effect of people's image brightness, shooting effect is improved, solves the technical problem that cannot realize the effect forced down background luminance and lift people's image brightness at the same time in the prior art.

Description

Imaging method, device, mobile terminal and storage medium

technical field

The present application relates to the technical field of image processing, and in particular to an imaging method, device, mobile terminal and storage medium.

Background technique

In recent years, the camera module technology of mobile terminals has developed greatly, and the quality of photos taken by mobile terminals is getting better and better. However, due to the small size of the mobile terminal and the camera module, there is still a certain gap between the shooting effect of the mobile terminal and professional camera equipment.

In some scenes in daily life, the video or photo taken by the mobile terminal cannot achieve the desired effect. For example, in a sunset scene, when shooting a person with the sunset as the background, if the camera module automatically adjusts the shooting parameters according to the shooting scene, the background may be overexposed, and the portrait may be underexposed, affecting the overall shooting effect.

application content

The application provides an imaging method, device, mobile terminal and storage medium. When shooting a person in a target scene with a low-light background, the background brightness is lowered by lowering the sensitivity ISO of the camera, and the person is imaged by turning on the flashlight. Fill light to achieve the effect of reducing the background brightness and increasing the brightness of the portrait at the same time, which improves the shooting effect.

An embodiment of the present application provides an imaging method, including:

When the framing picture belongs to the target scene, identify whether the framing picture contains a portrait; the background of the target scene is in a low-light state;

If the viewfinder contains portraits, lower the sensitivity ISO of the camera;

Turn on the flash to fill the portrait;

When the flash light is turned on, the camera is used to capture the viewfinder picture.

In the imaging method of the embodiment of the present application, when the viewfinder picture belongs to the target scene, identify whether there is a portrait in the viewfinder picture, wherein the background of the target scene is in a low-light state, if the viewfinder picture contains a portrait, lower the sensitivity ISO of the camera , and turn on the flash to fill in the light on the portrait. With the flash turned on, use the camera to take pictures of the viewfinder. In this embodiment, when shooting a person in a target scene where the background is in a low-light state, the background brightness is lowered by lowering the sensitivity ISO of the camera, and the portrait is supplemented by turning on the flashlight, thereby simultaneously reducing the background brightness and The effect of enhancing the brightness of the portrait improves the shooting effect, and solves the technical problem that the effects of reducing the brightness of the background and enhancing the brightness of the portrait cannot be simultaneously realized in the prior art.

Another embodiment of the present application provides an imaging device, including:

The recognition module is used to identify whether the viewfinder contains a portrait when the viewfinder belongs to the target scene; the background of the target scene is in a low-light state;

An adjustment module, configured to lower the sensitivity ISO of the camera if the viewfinder contains portraits;

A fill light module, used to turn on the flash to fill the portrait;

The control module is configured to use the camera to capture the framing picture when the flash is turned on.

The imaging device of the embodiment of the present application recognizes whether the viewfinder contains a portrait when the viewfinder belongs to the target scene, wherein the background of the target scene is in a low-light state, and if the viewfinder contains a portrait, lower the sensitivity ISO of the camera. , and turn on the flash to fill in the light on the portrait. With the flash turned on, use the camera to take pictures of the viewfinder. In this embodiment, when shooting a person in a target scene where the background is in a low-light state, the background brightness is lowered by lowering the sensitivity ISO of the camera, and the portrait is supplemented by turning on the flashlight, thereby simultaneously reducing the background brightness and The effect of enhancing the brightness of the portrait improves the shooting effect, and solves the technical problem that the effects of reducing the brightness of the background and enhancing the brightness of the portrait cannot be simultaneously realized in the prior art.

Another embodiment of the present application provides a mobile terminal, including: a camera, a flashlight, a memory, a processor, and a computer program stored on the memory and operable on the processor. When the processor executes the program, the following The imaging method described above in the embodiment of the present application.

Still another embodiment of the present application provides a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the imaging method as described in the above-mentioned embodiments of the present application is implemented.

Additional aspects and advantages of the application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the application.

Description of drawings

The above and/or additional aspects and advantages of the present application will become apparent and easy to understand from the following description of the embodiments in conjunction with the accompanying drawings, wherein:

FIG. 1 is a schematic flow chart of an imaging method provided in an embodiment of the present application;

FIG. 2 is a schematic flow chart of another imaging method provided in the embodiment of the present application;

FIG. 3 is a schematic flow chart of another imaging method provided in the embodiment of the present application;

Fig. 4 is a schematic diagram of the principle of triangular ranging;

FIG. 5 is a schematic structural diagram of an imaging device provided by an embodiment of the present application;

FIG. 6 is a schematic structural diagram of another imaging device provided by an embodiment of the present application;

FIG. 7 is a schematic structural diagram of a mobile terminal provided in an embodiment of the present application;

Fig. 8 is a schematic diagram of an image processing circuit in one embodiment.

Detailed ways

Embodiments of the present application are described in detail below, examples of which are shown in the drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary, and are intended to explain the present application, and should not be construed as limiting the present application.

The following describes the imaging method, device, mobile terminal, and storage medium of the embodiments of the present application with reference to the accompanying drawings.

In some scenes in daily life, the background is in a low-light state, and the scene in which the background is in a low-light state is hereinafter referred to as a target scene. In the target scene, the background needs to be clearly imaged despite being in a low-light state. Moreover, the background usually contains a light source, so that when the portrait in the target scene is in a backlit state, the detailed features cannot be clearly imaged, and the video or photo containing the portrait taken by the mobile terminal cannot achieve the desired effect.

For example, when the target scene is a sunset scene or a sunrise scene, in such a scene, both the background and the portrait need to be able to be clearly imaged. But in fact, because the background contains a light source, and the person is between the light source and the camera, the portrait is backlit. However, this kind of backlighting is different from backlighting in general situations. In this scene, while the brightness of the background is greater than the brightness of the portrait, the overall brightness of the background is darker, and it is in a weak light state where the average brightness is lower than the first threshold brightness. If the camera mode The group automatically adjusts the shooting parameters according to the average brightness, which may cause the overexposure of the light source area in the background whose brightness is higher than the second threshold brightness, and the portrait may be underexposed. At the same time, in the imaging image, the overall background is distorted due to too bright, affect the overall shooting effect.

In response to this problem, this application proposes an imaging method. When shooting a person in a target scene with a low-light background, the background brightness is lowered by lowering the sensitivity of the camera, and the flashlight is turned on to supplement the light of the person. In order to achieve the effect of simultaneously reducing the brightness of the background and increasing the brightness of the portrait, the shooting effect is improved.

FIG. 1 is a schematic flowchart of an imaging method provided in an embodiment of the present application.

As shown in Figure 1, the imaging method includes:

Step 101, when the framing frame belongs to the target scene, identify whether the framing frame contains a portrait; the background of the target scene is in a low-light state.

In target scenes such as sunset scenes or sunrise scenes, the background brightness is generally dark. When shooting people, the background brightness is often greater than the brightness of the portrait, and the brightness difference between the portrait and the background is large. The background effect is good, but the portrait is darker, and if the brightness of the portrait is increased, the background may be overexposed.

In this embodiment, when the viewfinder picture belongs to a scene where the background is in a low-light state, it is identified whether the viewfinder picture contains a portrait.

As a possible implementation, the contour data of the human body is pre-stored in mobile terminals such as mobile phones and tablet computers, wherein the data of the human body contour can be multiple, including human body contours corresponding to human body contours from different angles such as front and side data. When the user uses the camera of the mobile terminal to take pictures, after the camera captures the viewfinder picture, it extracts the outline of the object in the viewfinder picture, and then compares it with the pre-stored human body outline. If the extracted outline is consistent with at least one of the multiple pre-stored human outlines, it can be determined that the viewfinder contains a portrait.

As another possible implementation manner, a manner of face detection may be adopted, and when a human face is detected in the viewfinder picture, it is determined that the viewfinder picture contains a portrait. As an example, the face contour data and the data of feature points such as nose, eyes, mouth, and ears can be pre-stored in the mobile terminal, wherein the face contour data includes contour data such as frontal face and side face, and can also be Includes contour data for different face shapes. In the framing screen, extract the contour of the object to compare with the pre-stored human face contours. If the extracted contour is consistent with at least one of the pre-stored human face contours, then extract it from the area surrounded by the human face contours in the framing screen. The key feature points are compared with the pre-stored data of feature points such as nose, eyes, and mouth to further determine whether there is a human face in the viewfinder. Optionally, face detection can also be performed based on the principle of opencv face detection, so as to determine whether the viewfinder contains a portrait.

It should be noted that the shooting in this embodiment may be a photo taken by a mobile terminal with a camera function, or it may be a video taken.

Step 102, if the viewfinder contains a portrait, lower the sensitivity ISO of the camera.

Among them, the sensitivity ISO is used to measure the sensitivity of the film to light, and in digital cameras, it is used to measure the sensitivity of the photosensitive device to light. In the case of the same aperture, shutter speed and other conditions, the higher the sensitivity ISO, the brighter the captured picture.

In this embodiment, when it is determined that the framing picture belonging to the target scene contains a portrait, the sensitivity ISO of the camera is lowered to lower the brightness of the background to make the background darker. At present, the values of sensitivity ISO are 100, 200, 400, 800, etc. The larger the value of sensitivity ISO, the brighter the image will be when the aperture, shutter speed and other conditions are the same. During specific implementation, the sensitivity ISO value of the camera can be lowered by one or more grades to lower the background brightness.

For example: 4 ISO levels can be set, the values are 100, 200, 400, 800 respectively. You can set the ISO to 400 when the measured ISO should be 800.

It should be noted that the ISO grades and corresponding value-taking methods in this embodiment are only examples, and cannot be used to limit this embodiment. Those skilled in the art can know that they are not limited to the methods provided in this embodiment, and other methods can also be used. ISO grade and corresponding value selection method.

Step 103, turn on the flash to supplement light on the portrait.

Because the brightness of the portrait is lower than the brightness of the background, when the target scene contains portraits, after lowering the sensitivity ISO, the background brightness will be further reduced, but at the same time the portraits cannot be clearly imaged, so you can turn on the flash fill light. Generally speaking, the fill light range of the flash is small, and turning on the flash to fill the portrait has little effect on the imaging of the background.

Specifically, the camera module in the camera is controlled to stop operations such as automatic light metering and parameter adjustment, wherein the automatic light metering and parameter adjustment operations of the camera module include the light metering calculation of the automatic focus point or the light metering point of the current portrait, to Adjust the aperture, shutter speed, sensitivity ISO and other values. After the camera module stops operations such as automatic light metering and parameter adjustment, the mobile terminal sends a start command to the flash. After the flash light receives the turn-on command, the flash light is turned on to fill the portrait and increase the brightness of the portrait.

Step 104 , using the camera to capture a viewfinder picture when the flash is turned on.

When the flashlight is turned on, after the user clicks the shooting button, the mobile terminal receives a shooting instruction, and the mobile terminal uses the camera to take a viewfinder picture according to the shooting instruction. Alternatively, after the flash is turned on for a preset time period, such as 0.1s, the mobile terminal uses the camera to take a viewfinder picture when the flash is turned on. Therefore, it is possible to achieve a shooting effect that not only lowers the brightness of the background but also increases the brightness of the portrait.

In order to clearly describe the previous embodiment, in this embodiment, the target scene is specifically a sunset scene or a sunrise scene as an example for description. In the sunset scene and the sunrise scene mentioned in this embodiment, it is very important to confirm whether the shooting scene is a sunset scene or a sunrise scene. The imaging method proposed in this application will be explained below through another embodiment. FIG. 2 is a schematic flowchart of another imaging method provided by the embodiment of the present application.

As shown in Figure 2, the imaging method includes:

Step 201, acquiring the average brightness of the background in the framing picture.

When a user uses a mobile terminal with a camera to take pictures, the mobile terminal can display a preview viewfinder picture. After acquiring the viewfinder picture, the background of the viewfinder picture may be divided into multiple regions, the brightness of each region may be obtained, and then the average brightness of the background in the viewfinder picture may be calculated.

Step 202, if the average brightness of the background is lower than the first threshold brightness, identify whether the background in the viewfinder contains a light source area whose brightness is higher than the second threshold brightness.

In sunset or sunrise scenes, the background often includes the sun and the sky, and sometimes there are clouds in the sky, causing the overall background to be dark, and the brightness of each part of the area is still uneven. In the embodiment of the present application, the average brightness of the background is compared with the preset first threshold brightness. When the background brightness is lower than the first threshold brightness, it means that the background is relatively dark, and then it is identified whether the background in the viewfinder contains a brightness higher than The area of the light source for the second threshold brightness. Wherein, the second threshold luminance is greater than the first threshold luminance, the light source area can be understood as a relatively high luminance area in the background, through the above process, it is determined whether the luminance of each part of the background is uneven.

Specifically, the position and size of the light source area in the framing screen are preset. For example, if the set light source area is a rectangle, the size can be the length and width of the rectangle. If the set light source is a circle, the size can be is the radius of the circle. At the position set in the framing screen, the limited range of the light source area can be obtained according to the set size. In the framing screen within the limited range, the pixel value of each pixel is obtained, and it is judged according to the pixel value whether there is one or Multiple contiguous area ranges. If it exists, the continuous area range can be determined as the light source area.

Then, the brightness of the light source area in the viewfinder picture is acquired, and compared with the second threshold brightness. If the brightness of the light source area is higher than the second threshold brightness, then the light source area may be affected by sunrise or sunset.

Step 203, if it is recognized that the background in the viewfinder picture contains a light source area, the shooting time is acquired.

Due to the backlight scene during the day and the starry sky scene at night, in some cases, the overall background is dark and the brightness of each part of the background is uneven. In order to eliminate the backlight scene during the day and the starry sky scene at night, it is not necessary to lower the background. Brightness, the scene where the brightness of the portrait is increased. When the background in the viewfinder contains a light source area whose brightness is higher than the second threshold brightness, the mobile terminal obtains the current shooting time, so as to exclude the backlight scene during the day and the starry sky scene at night through the shooting time.

Step 204, if the shooting time belongs to the sunrise time period or the sunset time period, determine that the viewfinder picture belongs to the sunset scene or the sunrise scene.

As a possible implementation, because of different seasons in the same region, the sunset time or sunrise time is different, and in the same season, regions belonging to different time zones have different sunrise time or sunset time. Therefore, in the embodiment of the present application, the user can manually set the sunrise time period or the sunset time period according to the region and season. For example, Beijing is located in East Eighth District, while Urumqi is located in East Sixth District. The time difference is two hours. Users living in Beijing can set the sunrise time from 4:50 to 5:40, and users in Urumqi can set The sunrise time can be set from 6:50 to 7:50. After acquiring the shooting time, the mobile terminal compares the shooting time with the sunrise time period and the sunset time period set by the user to determine whether the shooting time belongs to the sunset time period or the sunrise time period.

As another possible implementation, it may be determined whether the current shooting time belongs to a sunrise period or a sunset period by interacting with the server. Specifically, the mobile terminal sends a query request to the server, and the query request carries the shooting time and shooting location. After receiving the request, the server queries the sunrise and sunset times of the day at the shooting location, and compares the shooting time sent by the mobile terminal with the sunrise and sunset times. If the shooting time belongs to the sunrise or sunset period, the server sends to the mobile terminal the query result that the shooting time belongs to the sunrise or sunset period; if the shooting time does not belong to the sunrise or sunset period, the server sends the mobile terminal Query results for time of day or sunset. After the mobile terminal receives the returned query result, if the result belongs to the sunrise time period or the sunset time period, it can determine that the viewfinder picture belongs to the sunrise scene or the sunset scene.

In this embodiment, by judging whether the shooting time belongs to the sunrise time period or the sunset time period, night street light scenes, daytime backlight scenes, night starry sky scenes, etc. can be excluded, thereby improving the judgment accuracy of sunset scenes or sunrise scenes.

Step 205, when the framing frame belongs to a sunset scene or a sunrise scene, identify whether the framing frame contains a portrait.

For a specific method for identifying whether a portrait is included in the viewfinder picture, refer to the relevant content recorded in the above-mentioned embodiments, and details are not repeated here.

Step 206, if the viewfinder contains portraits, lower the sensitivity ISO of the camera.

In this embodiment, when it is determined that the framing picture belonging to the sunset scene or the sunrise scene contains a portrait, the sensitivity ISO of the camera is lowered, the background brightness is lowered, and the background is darkened.

Step 207, turn on the flash to supplement light on the portrait.

Because the brightness of the portrait is lower than the brightness of the background, when the viewfinder of the sunset scene or the sunrise scene contains portraits, after lowering the sensitivity ISO, the background brightness will be further reduced, but at the same time the portraits cannot be clearly imaged, so you can turn on the flash Fill light on portraits. Generally speaking, the fill light range of the flash is small, and turning on the flash to fill the portrait has little effect on the imaging of the background.

Specifically, the camera module in the camera is controlled to stop operations such as automatic light metering and parameter adjustment. After the camera module stops operations such as automatic light metering and parameter adjustment, the mobile terminal sends a start command to the flash. After the flash light receives the turn-on command, the flash light is turned on to fill the portrait and increase the brightness of the portrait.

Step 208 , using the camera to capture a viewfinder picture when the flash is turned on.

When the flashlight is turned on, after the user clicks the shooting button, the mobile terminal receives a shooting instruction, and the mobile terminal uses the camera to take a viewfinder picture according to the shooting instruction. Alternatively, after the flash is turned on for a preset time period, such as 0.1s, the mobile terminal uses the camera to take a viewfinder picture when the flash is turned on. Therefore, it is possible to achieve a shooting effect that not only lowers the brightness of the background but also increases the brightness of the portrait.

For example, when shooting a person in a sunset scene, by lowering the sensitivity ISO and turning on the flash, the brightness of the portrait can be increased and the background brightness of the sunset can be lowered at the same time.

The imaging method of the embodiment of the present application determines whether the viewfinder picture is a sunset scene or a sunrise scene by judging whether the background of the viewfinder picture contains a light source area that satisfies the conditions, and the time period to which the shooting time belongs, thereby providing support for subsequent operations. Base.

In order to further improve the judgment accuracy of the sunset scene or the sunrise scene, weather information can be used to exclude the situation that the sunset or sunrise is not visible due to bad weather.

Specifically, after step 202, the mobile terminal may obtain weather information of the current shooting location from the server, and further determine whether the weather information of the shooting location is sunny or cloudless. If the weather information of the current shooting location is not sunny or cloudy, it can be determined that the sunrise or sunset is not visible, so that it can be determined that the framing picture does not belong to the sunrise scene or the sunset scene. If the weather information of the current shooting location is sunny or cloudy, and the current shooting time is during sunrise or sunset, it can be more confirmed that the viewfinder picture belongs to a sunrise scene or a sunset scene.

Furthermore, due to the refraction of the sun's rays by the atmosphere at sunrise and sunset, the emitted visible light is warmer. Human eyes can often see red to orange sun at sunrise and sunset, so this embodiment can also check whether the viewfinder picture belongs to the sunset scene or the sunrise scene according to the color temperature of the light source area in the background.

Specifically, after it is determined in step 202 that the framing screen contains the light source area, the average color temperature of the light source area is acquired, and then the average color temperature is compared with the threshold color temperature. If the average color temperature of the light source area is lower than the threshold color temperature, and the shooting time belongs to the sunrise period or the sunset period, it can be more sure that the framing picture belongs to the sunrise scene or the sunset scene.

It can be understood that when judging whether the viewfinder picture belongs to a sunset scene or a sunrise scene, the weather information of the shooting location, the average color temperature of the light source area, the time period of the shooting time, etc., all meet the conditions at the same time, and determine that the viewfinder picture belongs to the sunset scene. scene or sunrise scene.

When the viewfinder contains a portrait, if the photographed person is far away from the camera, even if the flash is turned on, the fill light effect cannot be achieved. The embodiment of the present application proposes that when the distance between the person and the camera satisfies the condition, turn on the camera Make fill light. Hereinafter, with reference to FIG. 3 , another embodiment will be described in detail.

As shown in Figure 3, the imaging method includes:

Step 301, when the framing frame belongs to the target scene, identify whether the framing frame contains portraits; the background of the target scene is in a low-light state.

In this embodiment, when the viewfinder picture belongs to a scene where the background is in a low-light state, it is identified whether the viewfinder picture contains a portrait. For a specific identification method, reference may be made to relevant content recorded in the foregoing embodiments, and details are not repeated here.

Step 302, if the viewfinder contains portraits, lower the sensitivity ISO of the camera.

In this embodiment, when it is determined that the framing picture belonging to the target scene contains a portrait, the sensitivity ISO of the camera is lowered to lower the brightness of the background to make the background darker. During specific implementation, the value of the sensitivity ISO of the camera may be lowered by one grade or multiple grades.

Step 303, when the ratio of the area occupied by the portrait in the viewfinder screen is greater than the threshold ratio, identify the distance between the person corresponding to the portrait and the camera.

It is understandable that when shooting, when the person is at a certain distance from the camera, the camera can only be turned on to achieve the purpose of filling the portrait.

Generally, the smaller the distance between the person and the camera, the larger the proportion of the area occupied by the person in the viewfinder. Thus, it can be judged first whether the proportion of the area occupied by the portrait in the framing screen is greater than the threshold ratio, such as the threshold ratio is When the proportion of the area occupied by the portrait in the framing screen is greater than the threshold proportion, identify the distance between the person corresponding to the portrait and the camera.

As a possible implementation, the distance between the person and the plane where the camera is located can be calculated through the principle of triangulation distance measurement. Based on Figure 4, in the actual space, the imaged person, the positions O _l and O _r of the two cameras, and the focal planes of the two cameras are drawn, and the distance between the focal plane and the plane where the two cameras are located is f.

p and p' are respectively the positions of the same person in different captured images. Wherein, the distance between point p and the left boundary of the captured image is x _l , and the distance between point p′ and the left boundary of the captured image is x _r . O _l and O _r are two cameras respectively, the two cameras are on the same plane, and the distance between the two cameras is Z.

Based on the triangular ranging principle, the distance b between the person in Figure 4 and the plane where the two cameras are located has the following relationship:

Based on this, it can be deduced Among them, d is the distance difference between the positions of the same person in different captured images. Since Z and f are fixed values, the distance b between the person and the plane where the camera is located can be determined according to d.

As another possible implementation, an infrared rangefinder is installed next to the camera. When the camera is shooting, the infrared rangefinder emits infrared rays to the person and receives the infrared rays reflected back by the person. The time it takes to receive the reflected infrared rays can calculate the distance between the person and the camera.

Step 304, determine that the distance between the person and the camera is not greater than the maximum effective distance of the flash, and turn on the flash to supplement the light on the portrait.

After identifying the distance between the person and the camera, compare the distance between the person and the camera with the maximum effective distance of the flash. When the distance between the person and the camera is not greater than the maximum effective distance of the flash, the flash can achieve the role of supplementary light on the portrait, so a command to turn on the flash is sent. The flash is turned on according to the turn-on command to fill in light on the portrait.

Step 305, using the camera to capture a viewfinder picture when the flash is turned on.

When the flashlight is turned on, after the user clicks the shooting button, the mobile terminal receives a shooting instruction, and the mobile terminal uses the camera to take a viewfinder picture according to the shooting instruction. Alternatively, after the flash is turned on for a preset period of time, such as 0.1s, the camera is used to take a viewfinder picture while the flash is turned on. Therefore, it is possible to achieve a shooting effect that not only lowers the brightness of the background but also increases the brightness of the portrait.

Step 306 , if the distance between the person and the camera is greater than the maximum effective distance of the flash, the camera is used to take a viewfinder picture when the flash is not turned on to obtain the target image.

When the distance between the person and the camera is greater than the maximum effective distance of the flash, the flash cannot achieve the fill light effect on the portrait. Therefore, the camera is used to capture the viewfinder and obtain the target image when the flash is not turned on.

Step 307, identifying the portrait area in the target image.

In order to improve the shooting effect, you can increase the brightness of the portrait area. Specifically, the contours of multiple objects in the target image can be extracted, and then the extracted contours can be compared with pre-stored human body contours, so as to identify the portrait area in the target image.

Step 308, increase the brightness of the portrait area in the target image.

After the portrait area in the target image is identified, the brightness of the portrait area in the target image is increased to improve the display effect of the portrait in the target image.

Since the brightness of the portrait area is increased, the brightness of the portrait area and the surrounding area may appear abrupt. Existing edge smoothing algorithms, such as mean filtering and Gaussian filtering, can be used to smooth the edges of the portrait area. The brightness transition between the portrait area and the surrounding area is smooth, thereby improving the display effect of the captured image.

Step 309, lower the brightness of the part of the target image except the portrait area.

In order to improve the overall display effect of the target image, further, the brightness of the parts other than the portrait area in the target image can be lowered to reduce the brightness difference between the portrait area and the parts other than the portrait area, thereby improving the overall brightness of the target image. display effect.

In the imaging method of the embodiment of the present application, the distance between the person corresponding to the portrait and the camera is compared with the maximum effective distance of the flashlight, and different processing methods are adopted according to the comparison results, and the processing method is relatively flexible.

In addition, when shooting, if you only want to shoot the scenery, but accidentally shoot unrelated people, you can tap the screen to focus, and use the camera to shoot the viewfinder without turning on the flash.

In the imaging method of the embodiment of the present application, when the viewfinder picture belongs to the target scene, identify whether there is a portrait in the viewfinder picture, wherein the background of the target scene is in a low-light state, if the viewfinder picture contains a portrait, lower the sensitivity ISO of the camera , and turn on the flash to fill in the light on the portrait. With the flash turned on, use the camera to take pictures of the viewfinder. In this embodiment, when shooting a person in a target scene where the background is in a low-light state, the background brightness is lowered by lowering the sensitivity ISO of the camera, and the portrait is supplemented by turning on the flashlight, thereby simultaneously reducing the background brightness and The effect of enhancing the brightness of the portrait improves the shooting effect, and solves the technical problem that the effects of reducing the brightness of the background and enhancing the brightness of the portrait cannot be simultaneously realized in the prior art.

The present application also proposes an imaging device. FIG. 5 is a schematic structural diagram of an imaging device provided by an embodiment of the present application.

As shown in FIG. 5 , the imaging device includes: an identification module 510 , an adjustment module 520 , a supplementary light module 530 , and a control module 540 .

Wherein, the identification module 510 is configured to identify whether the viewfinder picture contains a portrait when the viewfinder picture belongs to the target scene, and the background of the target scene is in a low-light state.

The adjustment module 520 is configured to lower the sensitivity ISO of the camera if the viewfinder contains portraits.

The supplementary light module 530 is used to turn on the flash to provide supplementary light for portraits.

The control module 540 is configured to use the camera to capture a viewfinder picture when the flashlight is turned on.

Specifically, the imaging device provided in the embodiment of the present application can execute the imaging method provided in the embodiment of the present application, and the device can be configured in a mobile terminal. Among them, there are many types of mobile devices, such as mobile phones, tablet computers, and notebook computers. FIG. 5 takes the mobile terminal as an example for a mobile phone.

In one embodiment of the present application, the target scene includes a sunset scene and/or a sunrise scene. On the basis of FIG. 5, as shown in FIG. , a second acquiring module 570 , and a determining module 580 .

The first acquiring module 550 is configured to acquire the average brightness of the background in the viewfinder picture.

The light source area identification module 560 is configured to identify whether the background in the viewfinder contains a light source area with a brightness higher than a second threshold brightness if the average brightness of the background is lower than the first threshold brightness; the second threshold brightness is greater than the first threshold brightness.

The second acquiring module 570 is configured to acquire the shooting time if it is recognized that the background in the viewfinder picture contains a light source area.

The determining module 580 is configured to determine that the viewfinder picture belongs to a sunset scene or a sunrise scene if the shooting time belongs to a sunrise time period or a sunset time period.

In an embodiment of the present application, the second acquisition module 570 is also used to acquire weather information of the shooting location;

The determining module 580 is further configured to determine that the weather information of the shooting location is sunny or cloudy.

In one embodiment of the present application, the second acquisition module 570 is also used to identify the average color temperature of the light source area in the viewfinder picture;

The determination module 580 is further configured to determine that the average color temperature is lower than the threshold color temperature.

Further, in an embodiment of the present application, the imaging device further includes:

The third acquisition module is used to identify the distance between the person corresponding to the portrait and the camera when the proportion of the area occupied by the portrait in the viewfinder screen is greater than the threshold ratio;

The determining module 580 is further configured to determine that the distance between the person and the camera is not greater than the maximum effective distance of the flashlight.

In one embodiment of the present application, the device may also include:

The control module 540 is also used for if the distance between the person and the camera is greater than the maximum effective distance of the flashlight, the camera is used to take a viewfinder picture when the flashlight is not turned on to obtain the target image.

The portrait area recognition module is used to identify the portrait area in the target image.

The brightness adjustment module is used to increase the brightness of the portrait area in the target image.

In an embodiment of the present application, the brightness adjustment module is further configured to lower the brightness of parts of the target image other than the portrait area.

The division of each module in the above imaging device is only for illustration. In other embodiments, the imaging device may be divided into different modules according to needs, so as to complete all or part of the functions of the above imaging device.

It should be noted that the foregoing explanations of the embodiment of the imaging method are also applicable to the imaging device of this embodiment, so details are not repeated here.

The imaging device of the embodiment of the present application recognizes whether the viewfinder contains a portrait when the viewfinder belongs to the target scene, wherein the background of the target scene is in a low-light state, and if the viewfinder contains a portrait, lower the sensitivity ISO of the camera. , and turn on the flash to fill in the light on the portrait. With the flash turned on, use the camera to take pictures of the viewfinder. In this embodiment, when shooting a person in a target scene where the background is in a low-light state, the background brightness is lowered by lowering the sensitivity ISO of the camera, and the portrait is supplemented by turning on the flashlight, thereby simultaneously reducing the background brightness and The effect of enhancing the brightness of the portrait improves the shooting effect, and solves the technical problem that the effects of reducing the brightness of the background and enhancing the brightness of the portrait cannot be simultaneously realized in the prior art.

The present application also proposes a mobile terminal. FIG. 7 is a schematic structural diagram of a mobile terminal provided by an embodiment of the present application.

As shown in FIG. 7 , the mobile terminal includes: a camera 710 , a flashlight 720 , a memory 730 , a processor 740 and a computer program stored in the memory 730 and operable on the processor 740 .

Wherein, when the processor 740 executes the program, the imaging method as described in any one of the foregoing embodiments is implemented.

The present application also proposes a computer-readable storage medium, on which a computer program is stored, and when the program is executed by a processor, the imaging method as described in any one of the foregoing embodiments is implemented.

The above mobile terminal further includes an image processing circuit, which may be implemented by hardware and/or software components, and may include various processing units defining an ISP (Image Signal Processing, image signal processing) pipeline. Fig. 8 is a schematic diagram of an image processing circuit in one embodiment. As shown in FIG. 8 , for ease of description, only various aspects of the image processing technology related to the embodiment of the present application are shown.

As shown in FIG. 8 , the image processing circuit includes an ISP processor 940 and a control logic 950 . Image data captured by imaging device 910 is first processed by ISP processor 940 , which analyzes the image data to capture image statistics that may be used to determine and/or control one or more parameters of imaging device 910 . The imaging device 910 may specifically include two cameras, and each camera may include one or more lenses 912 and an image sensor 914 . Image sensor 914 may include a color filter array (such as a Bayer filter), and image sensor 914 may obtain light intensity and wavelength information captured with each imaging pixel of image sensor 914 and provide a set of raw images that may be processed by ISP processor 940. image data. The sensor 920 may provide raw image data to the ISP processor 940 based on the sensor 920 interface type. The interface of the sensor 920 may utilize a SMIA (Standard Mobile Imaging Architecture, Standard Mobile Imaging Architecture) interface, other serial or parallel camera interfaces, or a combination of the above interfaces.

The ISP processor 940 processes raw image data on a pixel-by-pixel basis in various formats. For example, each image pixel may have a bit depth of 8, 10, 12, or 14 bits, and the ISP processor 940 may perform one or more image processing operations on raw image data, gather statistical information about the image data. Among other things, image processing operations can be performed with the same or different bit depth precision.

ISP processor 940 may also receive pixel data from image memory 930 . For example, raw pixel data is sent from the sensor 920 interface to the image memory 930, and the raw pixel data in the image memory 930 is provided to the ISP processor 940 for processing. The image memory 930 may be a part of a memory device, a storage device, or an independent dedicated memory in an electronic device, and may include a DMA (Direct Memory Access) feature.

Upon receiving raw image data from the sensor 920 interface or from the image memory 930, the ISP processor 940 may perform one or more image processing operations, such as temporal filtering. The processed image data may be sent to image memory 930 for additional processing before being displayed. The ISP processor 940 receives processed data from the image memory 930 and performs image data processing on the processed data in the raw domain and in the RGB and YCbCr color spaces. The processed image data may be output to the display 970 for viewing by the user and/or further processed by a graphics engine or a GPU (Graphics Processing Unit, graphics processor). In addition, the output of the ISP processor 940 can also be sent to the image memory 930 , and the display 970 can read image data from the image memory 930 . In one embodiment, image memory 930 may be configured to implement one or more frame buffers. Also, the output of the ISP processor 940 may be sent to an encoder/decoder 960 for encoding/decoding image data. The encoded image data may be saved and decompressed prior to display on the display 970 device. Encoder/decoder 960 may be implemented by a CPU or GPU or a coprocessor.

The statistics determined by the ISP processor 940 may be sent to the control logic 950 unit. For example, statistics may include image sensor 914 statistics such as auto exposure, auto white balance, auto focus, flicker detection, black level compensation, lens 912 shading correction, etc. Control logic 950 may include a processor and/or a microcontroller that executes one or more routines (e.g., firmware) that determine control parameters of imaging device 910 and control of imaging device 910 based on received statistical data. parameter. For example, control parameters may include sensor 920 control parameters (eg, gain, integration time for exposure control), camera flash control parameters, lens 912 control parameters (eg, focal length for focus or zoom), or combinations of these parameters. ISP control parameters may include gain levels and color correction matrices for automatic white balance and color adjustment (eg, during RGB processing), as well as lens 912 shading correction parameters.

In the description of this specification, descriptions referring to the terms "one embodiment", "some embodiments", "example", "specific examples", or "some examples" mean that specific features described in connection with the embodiment or example , structure, material or characteristic is included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the described specific features, structures, materials or characteristics may be combined in any suitable manner in any one or more embodiments or examples. In addition, those skilled in the art can combine and combine different embodiments or examples and features of different embodiments or examples described in this specification without conflicting with each other.

In addition, the terms "first" and "second" are used for descriptive purposes only, and cannot be interpreted as indicating or implying relative importance or implicitly specifying the quantity of indicated technical features. Thus, the features defined as "first" and "second" may explicitly or implicitly include at least one of these features. In the description of the present application, "plurality" means at least two, such as two, three, etc., unless otherwise specifically defined.

Any process or method descriptions in 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 custom logical functions or steps of a process , and the scope of preferred embodiments of the present application includes additional implementations in which functions may be performed out of the order shown or discussed, including in substantially simultaneous fashion or in reverse order depending on the functions involved, which shall It should be understood by those skilled in the art to which the embodiments of the present application belong.

The logic and/or steps represented in the flowcharts or otherwise described herein, for example, can be considered as a sequenced listing of executable instructions for implementing logical functions, can be embodied in any computer-readable medium, For use with instruction execution systems, devices, or devices (such as computer-based systems, systems including processors, or other systems that can fetch instructions from instruction execution systems, devices, or devices and execute instructions), or in conjunction with these instruction execution systems, devices or equipment for use. For the purposes of this specification, a "computer-readable medium" may be any device that can contain, store, communicate, propagate or transmit a program for use in or in conjunction with an instruction execution system, device or device. More specific examples (non-exhaustive list) of computer-readable media include the following: electrical connection with one or more wires (electronic device), portable computer disk case (magnetic device), random access memory (RAM), Read Only Memory (ROM), Erasable and Editable Read Only Memory (EPROM or Flash Memory), Fiber Optic Devices, and Portable Compact Disc Read Only Memory (CDROM). In addition, the computer-readable medium may even be paper or other suitable medium on which the program can be printed, since the program can be read, for example, by optically scanning the paper or other medium, followed by editing, interpretation or other suitable processing if necessary. The program is processed electronically and stored in computer memory.

It should be understood that each part of the present application may be realized by hardware, software, firmware or a combination thereof. In the embodiments described above, various steps or methods may be implemented by 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: a discrete Logic circuits, ASICs with suitable combinational logic gates, Programmable Gate Arrays (PGA), Field Programmable Gate Arrays (FPGA), etc.

Those of ordinary skill 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 related hardware through a program, and the program can be stored in a computer-readable storage medium. During execution, one or a combination of the steps of the method embodiments is included.

In addition, each functional unit in each embodiment of the present application may be integrated into one processing module, each unit may exist separately physically, or two or more units may be integrated into one module. The above-mentioned integrated modules can be implemented in the form of hardware or in the form of software function modules. If the integrated modules are realized in the form of software function modules and sold or used as independent products, they can also be stored in a computer-readable storage medium.

The storage medium mentioned above may be a read-only memory, a magnetic disk or an optical disk, and the like. Although the embodiments of the present application have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limitations on the present application, and those skilled in the art can make the above-mentioned The embodiments are subject to changes, modifications, substitutions and variations.

Claims (10)

1. a kind of imaging method, it is characterised in that method comprises the following steps：

When picture of finding a view belongs to target scene, whether portrait is included in picture of finding a view described in identification；The back of the body of the target scene Scape is in dim light state；

If including portrait in the picture of finding a view, the sensitivity ISO of camera is turned down；

Open flash lamp and light filling is carried out to portrait；

In the state of flash lamp unlatching, using picture of finding a view described in camera shooting.

2. imaging method according to claim 1, it is characterised in that the target scene includes setting sun scene and/or court Positive scene, it is described whether to identify in picture of finding a view comprising before portrait, further include：

The average brightness for the background in picture of finding a view described in acquisition；

If the average brightness of the background is less than first threshold brightness, whether the background in picture of finding a view described in identification includes brightness Higher than the source region of second threshold brightness；The second threshold brightness is more than the first threshold brightness；

If identifying, the background in the picture of finding a view includes source region, obtains shooting time；

If the shooting time belongs to sunrise period or sunset period, determine that the picture of finding a view belongs to setting sun scene or southern exposure field Scape.

3. imaging method according to claim 2, it is characterised in that described to determine that the picture of finding a view belongs to setting sun scene Or before southern exposure scene, further include：

Obtain the Weather information of spot for photography；

The Weather information for determining the spot for photography is sunny or partly cloudy weather.

4. imaging method according to claim 2, it is characterised in that described to determine that the picture of finding a view belongs to setting sun scene Or before southern exposure scene, further include：

Find a view described in identification the average color temperature of source region described in picture；

Determine that the average color temperature is less than threshold value colour temperature.

5. according to claim 1-4 any one of them imaging methods, it is characterised in that in the picture of finding a view comprising portrait it Afterwards, further include：

When being more than threshold percentage in the ratio of portrait occupied area described in picture of finding a view, identify that the portrait corresponds to personage The distance between described camera；

Determine that the distance between the personage and the camera are not more than the maximum effective distance of the flash lamp.

6. imaging method according to claim 5, it is characterised in that the identification portrait corresponds to personage and taken the photograph with described After the distance between head, further include：

If the distance between the personage and the camera are more than the maximum effective distance of the flash lamp, using the shooting Head, in the state of flash lamp is not opened, picture of finding a view described in shooting, obtains target image；

Identify the portrait area in the target image；

Brightness is heightened to the portrait area in the target image.

7. imaging method according to claim 6, it is characterised in that the portrait area tune in the target image After high brightness, further include：

To removing the portrait area in the target image with outer portion, brightness is turned down.

8. a kind of imaging device, it is characterised in that described device includes：

Identification module, for whether including portrait in picture of when picture of finding a view belongs to target scene, finding a view described in identification；It is described The background of target scene is in dim light state；

Module is adjusted, if for including portrait in the picture of finding a view, turns down the sensitivity ISO of camera；

Supplementary lighting module, light filling is carried out for opening flash lamp to portrait；

Control module, in the state of being opened in the flash lamp, using picture of finding a view described in camera shooting.

A kind of 9. mobile terminal, it is characterised in that including：Camera, flash lamp, memory, processor and it is stored in memory Computer program that is upper and can running on a processor, when the processor performs described program, is realized as in claim 1-7 Any one of them imaging method.

10. a kind of computer-readable recording medium, is stored thereon with computer program, it is characterised in that the program is by processor The imaging method as any one of claim 1-7 is realized during execution.