CN106506973A - Focus control method, device, electronic equipment and terminal equipment - Google Patents

Abstract

The application provides a focusing control method, a focusing control device, electronic equipment and terminal equipment, wherein the focusing control method comprises the following steps: acquiring a reference brightness value; determining a contrast compensation value according to the current brightness value of the picture to be shot and the reference brightness value detected in the focusing process; and compensating the contrast of the picture to be shot according to the contrast compensation value and then carrying out focusing treatment. Therefore, the contrast of the shot picture is not influenced by the scene brightness in the focusing process, and the focusing accuracy is ensured.

Description

Focus control method, device, electronic equipment and terminal equipment

technical field

The present application relates to the field of imaging technology, and in particular to a focus control method, device, electronic equipment and terminal equipment.

Background technique

With the development of smart phones, mobile phones are used more and more frequently to take pictures, and users have higher and higher requirements for the clarity of pictures. Not only do they require clear shots of normal indoor and outdoor scenes, but they also hope that they can be displayed in night scenes. Clearer, and to take clear pictures, the first thing to do is to focus accurately. Only when the focus is accurate can you take good photos. If the focus is not accurate or out of focus, the effect of the photos taken cannot meet the needs of users.

And because the accuracy of focusing largely depends on the accuracy of FV (Focus Value, focus value), FV represents the contrast of the scene, only the accuracy of FV can find the most accurate focus position. However, in reality, there are often inaccurate FV statistics due to large fluctuations in the brightness of the scene, which leads to the wrong focus position calculated by the autofocus algorithm, resulting in blurred photos.

Contents of the invention

This application aims to solve one of the technical problems in the related art at least to a certain extent.

Therefore, the first purpose of the present application is to propose a focus control method, which realizes that the contrast of the shooting picture is not affected by the brightness of the scene during the focus process, and ensures the accuracy of focus.

The second purpose of the present application is to provide a focus control device.

The third object of the present application is to provide an electronic device.

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

In order to achieve the above purpose, the embodiment of the first aspect of the present application proposes a focus control method, including: obtaining a reference brightness value; determining a contrast compensation value according to the current brightness value of the picture to be shot detected during the focusing process and the reference brightness value ; Perform focus processing after compensating the contrast of the picture to be shot according to the contrast compensation value.

In the focus control method of the embodiment of the present application, by obtaining a reference brightness value; determining a contrast compensation value according to the current brightness value of the picture to be shot detected during the focusing process and the reference brightness value; After the contrast of the screen is compensated, focus processing is performed. Thus, it is realized that the contrast of the shooting picture is not affected by the brightness of the scene during the focusing process, and the accuracy of focusing is ensured.

In order to achieve the above purpose, the embodiment of the second aspect of the present application proposes a focus control device, including: an acquisition module, used to acquire a reference brightness value; and the reference brightness value to determine a contrast compensation value; a processing module configured to perform focus processing after compensating the contrast of the picture to be shot according to the contrast compensation value.

The focus control device of the embodiment of the present application obtains a reference brightness value; determines a contrast compensation value according to the current brightness value of the picture to be shot detected during the focusing process and the reference brightness value; After the contrast of the screen is compensated, focus processing is performed. As a result, the contrast of the shooting screen is not affected by the brightness of the scene during the focusing process, ensuring the accuracy of focusing.

To achieve the above purpose, the embodiment of the third aspect of the present application provides an electronic device, including an imaging device, and the focus control device as provided in the second aspect.

The electronic equipment in the embodiment of the present application includes the focus control device in the embodiment of the second aspect. As a result, the contrast of the shooting screen is not affected by the brightness of the scene during the focusing process, ensuring the accuracy of focusing.

To achieve the above purpose, the embodiment of the fourth aspect of the present application proposes a terminal device, including a housing, a processor, a memory, an imaging device, and one or more of the following components: a power circuit, a multimedia component, an audio component, an input I/O (I/O) interface, sensor assembly, and communication assembly; wherein, the processor and the memory are arranged in the inner space surrounded by the housing; the power supply circuit is used for the mobile Each circuit or device of the terminal supplies power; the memory is used to store executable program code; the processor executes the program corresponding to the executable program code by reading the executable program code stored in the memory, to It is used to perform the following steps: acquiring a reference brightness value; determining a contrast compensation value according to the current brightness value of the picture to be shot detected during the focusing process and the reference brightness value; Perform focus processing after compensation.

The terminal device in the embodiment of the present application obtains a reference brightness value; determines a contrast compensation value according to the current brightness value of the picture to be shot detected during the focusing process and the reference brightness value; After the contrast is compensated, focus processing is performed. As a result, the contrast of the shooting screen is not affected by the brightness of the scene during the focusing process, ensuring the accuracy of focusing.

Additional aspects and advantages of the invention 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 invention.

Description of drawings

The above and/or additional aspects and advantages of the present invention 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 flowchart of a focus control method according to an embodiment of the present application;

FIG. 2 is a flowchart of a focus control method according to another embodiment of the present application;

FIG. 3 is a schematic structural diagram of a focus control device provided by an embodiment of the present application;

FIG. 4 is a schematic structural diagram of a focus control device provided by another embodiment of the present application;

FIG. 5 is a schematic structural diagram of an electronic device according to an embodiment of the present application;

Fig. 6 is a schematic structural diagram of a terminal device according to an embodiment of the present application.

detailed description

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.

FV (focus value, focus value) is usually the data obtained after processing the image output by the imaging device to represent the sharpness of the image. The information statistics of FV are to a large extent the contrast of the current scene. Generally, the image The higher the FV of , the higher the contrast of the in-focus scene. If the brightness of the current scene is relatively stable, the FV statistics of each frame should be relatively accurate, and if the brightness fluctuations are relatively large, the FV statistics will be seriously affected.

In particular, for the focusing process in the phase focusing mode, the change of the brightness of the scene will seriously affect the contrast of the picture to be shot. The focusing process of the phase focus mode usually includes a coarse search process and a fine search process. The coarse search process is usually based on the focus motor pushing the focus lens forward to the best focus position with a large step distance, and the best focus position is based on The calculated phase difference determines where the focusing lens should be. In the fine search process, the focus motor drives the focus lens to this position with a small step distance near the best focus position, and the image can be clearly imaged at the best focus position. Since the fine search is to search near the exact in-focus position (target clear position), it is necessary to find the corresponding focus position when the image clarity is the highest to achieve focus, and the image clarity needs to be characterized by FV, therefore, in the fine During the search process, it is necessary to count the focus value FV of the frame image at each fine search position of the focus lens, that is to say, the focus motor drives the focus lens every step forward, so as to find the corresponding focus position when the focus value FV is the largest. Achieve focus. Therefore, if the calculated focus value FV is inaccurate, the focus position with the highest definition cannot be found, resulting in focus failure. Therefore, in the process of focusing, it is particularly important to control the accuracy of the focus value FV of each frame.

The focus value FV is easily affected by the brightness of the scene. Therefore, in order to ensure the accuracy of focusing, it is necessary to control the influence of changes in scene brightness on the calculated focus value FV.

The embodiments of the present application aim to solve the above technical problems, and provide a focus control method, device, electronic equipment, and terminal equipment. The focus control method, device, electronic device, and terminal device according to the embodiments of the present application are described below with reference to the accompanying drawings.

FIG. 1 is a flowchart of a focus control method according to an embodiment of the present application. Specifically, the focus control method provided in this embodiment may be configured to be executed in an electronic device having an imaging device. It should be noted that there are many types of electronic devices, which can be selected according to actual needs, such as mobile phones and tablet computers.

As shown in Figure 1, the focus control method includes:

Step 101, obtaining a reference brightness value;

The reference brightness value is related to the scene that needs to be shot at present. Specifically, the reference brightness value can be obtained through the following methods:

A preferred manner is: detecting the corresponding scene brightness value when the focus is started to obtain a reference brightness value. Specifically, when the focus is started, the scene brightness value can be automatically detected, and the scene brightness value can be used as a reference brightness value.

Another optional manner is: acquiring currently captured scene characteristic information; querying a preset brightness information table to obtain a reference brightness value corresponding to the scene characteristic information.

Specifically, a brightness information table may be pre-stored in the memory, and reference brightness values corresponding to the scene feature information may be stored in the brightness information table. The scene feature information may include one or a combination of the following information. For example, the scene feature information includes the main attribute information of the currently shot scene, for example, the shot scene is a person, a landscape, food, etc., and/or Depending on the complexity of the background of the scene being photographed, the brightness values corresponding to scenes with different scene characteristics should also be different. Therefore, the matching relationship between the scene feature information and the brightness information can be formed. When it is necessary to obtain the reference brightness value, you can use the Query the brightness information table to get it.

Step 102, determining a contrast compensation value according to the current brightness value of the picture to be captured detected during the focusing process and the reference brightness value.

Step 103 , performing focus processing after compensating the contrast of the image to be captured according to the contrast compensation value.

During the focusing process, the FV value (focus value) of each frame will be continuously obtained to represent the contrast of the scene. If the brightness of the scene changes, the FV value of the corresponding frame will change due to the brightness of the scene during the movement of the focusing lens. If large fluctuations occur, the measured FV value at this time is inaccurate, so that the focusing lens cannot find the best focus position.

Usually, in the imaging process, it is first necessary to wait for the brightness of the shooting picture to be automatically adjusted, that is, to wait for the automatic exposure to stabilize. At the beginning of focusing, you can record the exposure value at this time (the exposure value reflects the Luma value, brightness). If the exposure value changes during the focusing process, it means that the brightness of the scene has changed, and exposure compensation will be performed. Exposure compensation is A control method for the exposure process, that is, to adjust the exposure value adopted by the automatic exposure, so as to meet the user's demand for the brightness of the picture. When the exposure value changes during focusing, for example, when the brightness of the screen is dark, the exposure value can be increased, and when the screen is bright, the exposure value can be decreased.

When the exposure value changes, it means that the brightness of the scene has changed. At this time, the contrast (that is, the FV value, focus value) also needs to be adjusted to prevent the fluctuation of the contrast of the image to be shot caused by the change of the scene brightness.

Since the brightness value of the picture to be shot often changes dynamically during the focusing process, which will also dynamically affect the contrast of the picture, therefore, the current brightness value of the picture to be shot can be monitored and compared with the current brightness value of the picture to be shot Real-time comparison of the reference brightness value to determine that the brightness of the scene has changed during the focusing process, and determine the required contrast compensation value according to the degree of brightness change, and dynamically perform contrast compensation on the picture to be shot according to the determined contrast compensation value .

In the focus control method of the embodiment of the present application, by obtaining a reference brightness value; determining a contrast compensation value according to the current brightness value of the picture to be shot detected during the focusing process and the reference brightness value; After the contrast of the screen is compensated, focus processing is performed. Thus, it is realized that the image contrast is dynamically adjusted according to the change of scene brightness during the focusing process, so that the contrast of the shooting image is not affected by the scene brightness during the focusing process, and the accuracy of focusing is ensured.

Based on the above embodiments, specifically, FIG. 2 is a flowchart of a focus control method according to another embodiment of the present application. This embodiment is basically the same as the embodiment shown in FIG. 1 . The difference from the embodiment shown in FIG. 1 is that the method for determining the contrast compensation value is further limited. As shown in FIG. 2 , the implementation of the focus control method in this embodiment Steps include:

Step 201, acquire a reference brightness value.

Step 202: Determine a contrast compensation coefficient according to the current brightness value and the reference brightness value.

Step 203, applying gamma correction to calculate the contrast compensation coefficient to determine a contrast compensation value.

Step 204 , performing focus processing after compensating the contrast of the image to be captured according to the contrast compensation value.

Specifically, in step 202, a preset algorithm may be used to calculate the current brightness value and the reference brightness value to determine the contrast compensation coefficient. Specifically, the preset algorithm is:

R=1.03 ^(AB)

Wherein, A is the current brightness value of the image to be captured, B is the reference brightness value, and R is the contrast compensation coefficient.

That is, pow(1.03f,bf_stats->ref_exp_index-aec_update->exp_index) is used to calculate the required contrast compensation coefficient. After many experiments and verifications, the contrast compensation coefficient determined in this way can achieve the contrast compensation effect most.

The so-called gamma correction is a method of editing the gamma curve of the image to perform nonlinear tone editing on the image, detecting the dark part and light part of the image signal, and increasing the ratio of the two, thereby improving the image quality. Image contrast effect. Gamma correction is a prior art, and will not be repeated here.

In addition, as another feasible way, for determining the contrast compensation value, it is also possible to query the corresponding relationship between the pre-stored brightness change amount and the contrast compensation value according to the current brightness value and the reference brightness value, so as to obtain the corresponding brightness change. Contrast compensation value.

To achieve the above purpose, the present application also provides a focusing control device. FIG. 3 is a schematic structural diagram of a focus control device provided by an embodiment of the present application. As shown in FIG. 3 , the focus control device 10 provided by this embodiment includes:

An acquisition module 11, configured to acquire a reference brightness value;

A determination module 12, configured to determine a contrast compensation value according to the current brightness value of the picture to be captured detected during the focusing process and the reference brightness value;

The processing module 13 is configured to perform focusing processing after compensating the contrast of the picture to be shot according to the contrast compensation value.

Further, the acquisition module 11 is specifically configured to: detect a corresponding scene brightness value when focusing is started to obtain a reference brightness value.

Alternatively, FIG. 4 is a schematic structural diagram of a focus control device provided in another embodiment of the present application. In this embodiment, the acquisition module 11 and the determination module 12 in the embodiment shown in FIG. 3 are further refined. Specifically, the Obtaining module 11 may include:

An acquiring unit 111, configured to acquire feature information of the currently photographed scene;

The query unit 112 is configured to query a preset brightness information table to obtain a reference brightness value corresponding to the scene characteristic information.

The determination module 12 may include:

A first determining unit 121, configured to determine a contrast compensation coefficient according to the current brightness value and the reference brightness value;

The second determination unit 122 is configured to apply gamma correction to calculate the contrast compensation coefficient to determine a contrast compensation value.

In the embodiment shown in FIG. 3 or FIG. 4 above, further, the first determination unit 121 is configured to: apply a preset algorithm to calculate the current brightness value and the reference brightness value, and determine the contrast compensation coefficient, wherein , the preset algorithm is:

R=1.03 ^(AB)

Wherein, A is the current brightness value of the image to be captured, B is the reference brightness value, and R is the contrast compensation coefficient.

It should be noted that, the function and processing flow of each module in the focus control device provided by this embodiment can be referred to the above method embodiment, and its implementation principle and technical effect are similar, and will not be repeated here.

The focus control device of the embodiment of the present application obtains a reference brightness value; determines a contrast compensation value according to the current brightness value of the picture to be shot detected during the focusing process and the reference brightness value; After the contrast of the screen is compensated, focus processing is performed. Thus, it is realized that the image contrast is dynamically adjusted according to the change of scene brightness during the focusing process, so that the contrast of the shooting image is not affected by the scene brightness during the focusing process, and the accuracy of focusing is ensured.

To achieve the above purpose, the present application also provides an electronic device. FIG. 5 is a schematic structural diagram of an electronic device according to an embodiment of the present application. As shown in FIG. 5, the electronic device includes an imaging device 1010, and the The focus control device 10 described above. The electronic device includes a mobile phone or a tablet computer. The imaging device includes a front camera and/or a rear camera.

Fig. 6 is a schematic structural diagram of a terminal device according to an embodiment of the present application. The terminal device in this embodiment may be a mobile phone.

As shown in FIG. 6, the terminal device 1000 may include one or more of the following components: a housing 1001, a processor 1002, a memory 1003, an imaging device 1010, and one or more of the following components: a power supply circuit 1004, a multimedia component 1005, Audio component 1006 , input/output (I/O) interface 1007 , sensor component 1008 , and communication component 1009 .

Wherein, the processor 1002 and the memory 1003 are arranged in the internal space surrounded by the housing 1001; the power supply circuit 1004 is used to supply power to each circuit or device of the mobile terminal 1000; the memory 1003 is used to store executable program codes; the processor 1002 reads Take the executable program code stored in the memory 1003 to run the program corresponding to the executable program code, so as to perform the following steps:

Obtain the reference brightness value;

determining a contrast compensation value according to the current brightness value of the picture to be shot detected during the focusing process and the reference brightness value;

Focusing processing is performed after compensating the contrast of the picture to be shot according to the contrast compensation value.

The terminal device in the embodiment of the present application obtains a reference brightness value; determines a contrast compensation value according to the current brightness value of the picture to be shot detected during the focusing process and the reference brightness value; After the contrast is compensated, focus processing is performed. Thus, it is realized that the image contrast is dynamically adjusted according to the change of scene brightness during the focusing process, so that the contrast of the shooting image is not affected by the scene brightness during the focusing process, and the accuracy of focusing is ensured.

In the description of this specification, descriptions with reference 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 modules, segments or portions of code comprising one or more executable instructions for implementing specific logical functions or steps of the 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 used. 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 combination of the following techniques known in the art: Discrete logic circuits, ASICs with suitable combinational logic gates, programmable gate arrays (PGAs), field programmable gate arrays (FPGAs), etc.

Claims (14)

1. a kind of focusing control method, it is characterised in that comprise the following steps：

Obtain reference brightness value；

Present intensity value and the reference brightness value according to the picture to be captured detected in focus process determines contrast compensation Value；

Focusing process is carried out after compensating to the contrast of the picture to be captured according to the contrast compensation value.

2. the method for claim 1, it is characterised in that the acquisition reference brightness value, including：

When detection focusing starts, corresponding scene illumination values are obtaining the reference brightness value.

3. the method for claim 1, it is characterised in that the acquisition reference brightness value, including：

Obtain the scene characteristic information of current shooting；

Inquire about default monochrome information table and obtain reference brightness value corresponding with the scene characteristic information.

4. the method as described in any one of claim 1-3, it is characterised in that described according in focus process detection to be captured The present intensity value and the reference brightness value of picture determines contrast compensation value, including：

Contrast compensation coefficient is determined according to the present intensity value and the reference brightness value；

Application gamma correction is carried out calculating to the contrast compensation coefficient and determines contrast compensation value.

5. method as claimed in claim 4, it is characterised in that determined according to the present intensity value and the reference brightness value Contrast compensation coefficient, including：

Application preset algorithm is calculated to the present intensity value and the reference brightness value, determines contrast compensation coefficient, Wherein, the preset algorithm is：

R=1.03^(A-B)

Wherein, A is the present intensity value of picture to be captured, and B is reference brightness value, and R is contrast compensation coefficient.

6. a kind of focusing control apparatus, it is characterised in that include：

Acquisition module, for obtaining reference brightness value；

Determining module, true for the present intensity value and the reference brightness value according to the picture to be captured detected in focus process Determine contrast compensation value；

Processing module is right for carrying out after being compensated to the contrast of the picture to be captured according to the contrast compensation value Burnt process.

7. focusing control apparatus as claimed in claim 6, it is characterised in that

The acquisition module specifically for：When detection focusing starts, corresponding scene illumination values are obtaining reference brightness value.

8. focusing control apparatus as claimed in claim 6, it is characterised in that the acquisition module includes：

Acquiring unit, for obtaining the scene characteristic information of current shooting；

Query unit, obtains reference brightness value corresponding with the scene characteristic information for inquiring about default monochrome information table.

9. focusing control apparatus as described in any one of claim 6-8, it is characterised in that the determining module includes：

First determining unit, for determining contrast compensation coefficient according to the present intensity value and the reference brightness value；

Second determining unit, determines contrast compensation for applying gamma correction to carry out the contrast compensation coefficient to calculate Value.

10. focusing control apparatus as claimed in claim 9, it is characterised in that

First determining unit has to be used for：Application preset algorithm is carried out to the present intensity value and the reference brightness value Calculate, determine contrast compensation coefficient, wherein, the preset algorithm is：

R=1.03^(A-B)

Wherein, A is the present intensity value of picture to be captured, and B is reference brightness value, and R is contrast compensation coefficient.

11. a kind of electronic installations, it is characterised in that including imaging device and right as described in any one of claim 6-10 Burnt control device.

12. electronic installations according to claim 11, it is characterised in that the electronic installation includes mobile phone or flat board electricity Brain.

13. electronic installations according to claim 11, it is characterised in that the imaging device include Front camera and/or Rearmounted camera.

14. a kind of terminal units, it is characterised in that including housing, processor, memorizer, imaging device, and with next or Multiple components：Power circuit, multimedia groupware, audio-frequency assembly, the interface of input/output (I/O), sensor cluster, Yi Jitong Letter component；Wherein, the processor and the memorizer are arranged on the inner space that the housing is surrounded；The power circuit, Power for each circuit or device for the mobile terminal；The memorizer is used for storing executable program code；Described Processor is corresponding with the executable program code to run by the executable program code for reading storage in the memorizer Program, for execute following steps：

Obtain reference brightness value；

Present intensity value and the reference brightness value according to the picture to be captured detected in focus process determines contrast compensation Value；

Focusing process is carried out after compensating to the contrast of the picture to be captured according to the contrast compensation value.