CN107197169A - A kind of high dynamic range images image pickup method and mobile terminal - Google Patents

Abstract

The present invention provides a high dynamic range image shooting method and a mobile terminal. The method includes: acquiring a first preview image collected by a first camera; determining a foreground image area and a background image area in the first preview image; instruction, respectively acquire the second preview image collected by the first camera and the third preview image collected by the second camera; perform image synthesis processing on the second preview image and the third preview image, and output a high A dynamic range image; wherein, the second preview image is an image exposed to the foreground image area, and the third preview image is an image exposed to the background image area. According to the high dynamic range image shooting method provided by the embodiment of the present invention, the mobile terminal can avoid the time difference between the photos used to synthesize the HDR image, thereby reducing the occurrence of ghosting or afterimage, and improving the quality of the photos taken by the mobile terminal.

Description

A high dynamic range image shooting method and mobile terminal

technical field

The invention relates to the field of communication technology, in particular to a high dynamic range image shooting method and a mobile terminal.

Background technique

With the development of communication technology, mobile terminals such as mobile phones and tablet computers have become indispensable tools in people's daily life. In order to meet the requirements of the camera function of mobile terminals, high-dynamic range (High-Dynamic Range, HDR) image capture technology is gradually applied to mobile terminals, and mobile terminals can capture long-exposure, short-exposure and normal-exposure photos respectively through the camera. , and synthesize multiple captured photos to obtain an HDR image, and the synthesized HDR image has a more balanced exposure effect, thereby improving the quality of photos taken by the mobile terminal.

However, when the mobile terminal adopts the HDR technology to take pictures, since there will be a time difference of two or three frames when the mobile terminal continuously captures two pictures, if the mobile terminal is in motion or the object to be photographed is in motion, the two pictures captured continuously The image of the photo changes, causing ghosting or afterimage phenomenon in the synthesized HDR image, which reduces the quality of the photo taken by the mobile terminal. It can be seen that the current mobile terminal has the problem of low photo quality due to heavy ghosting or afterimage during the photo taking process.

Contents of the invention

Embodiments of the present invention provide a high dynamic range image shooting method and a mobile terminal, so as to solve the problem of low quality of photos caused by ghosting or severe residual images during the shooting process of the mobile terminal.

In the first aspect, an embodiment of the present invention provides a high dynamic range image shooting method, which is applied to a mobile terminal with a first camera and a second camera arranged on one side, and the method includes:

Obtain the first preview image collected by the first camera;

determining a foreground image area and a background image area in the first preview image;

If a photographing instruction is received, respectively acquire a second preview image collected by the first camera and a third preview image collected by the second camera;

performing image synthesis processing on the second preview image and the third preview image, and outputting a high dynamic range image;

Wherein, the second preview image is an image exposed to the foreground image area, and the third preview image is an image exposed to the background image area.

In the second aspect, an embodiment of the present invention further provides a mobile terminal, where a first camera and a second camera are arranged on one side of the mobile terminal, and the mobile terminal further includes:

The first image acquisition module is used to acquire the first preview image collected by the first camera;

an area determination module, configured to determine a foreground image area and a background image area in the first preview image acquired by the first image acquisition module;

The second image acquisition module is configured to acquire the second preview image collected by the first camera and the third preview image collected by the second camera respectively if a photographing instruction is received;

A synthesis module, configured to perform image synthesis processing on the second preview image and the third preview image acquired by the second image acquisition module, and output a high dynamic range image;

Wherein, the second preview image is an image exposed to the foreground image area determined by the area determination module, and the third preview image is an image exposed to the background image area determined by the area determination module.

In the third aspect, the embodiment of the present invention also provides a mobile terminal, a first camera and a second camera are arranged on one side of the mobile terminal, and the mobile terminal further includes a processor, a memory, stored in the memory and A computer program that can run on the processor, when the computer program is executed by the processor, the steps of the above-mentioned high dynamic range image shooting method are realized.

In a fourth aspect, an embodiment of the present invention further provides a computer-readable storage medium, where a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the steps of the above-mentioned high dynamic range image capture method are implemented .

In this way, in the embodiment of the present invention, the first preview image captured by the first camera is acquired; the foreground image area and the background image area in the first preview image are determined; The second preview image collected and the third preview image collected by the second camera; image synthesis processing is performed on the second preview image and the third preview image, and a high dynamic range image is output; wherein, the second The preview image is an image exposed to the foreground image area, and the third preview image is an image exposed to the background image area. The mobile terminal can avoid the time difference between photos used for synthesizing the HDR image, thereby reducing the occurrence of ghosting or afterimage, and improving the quality of photos taken by the mobile terminal.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings that need to be used in the description of the embodiments of the present invention. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained based on these drawings without any creative effort.

Fig. 1 is one of the flow charts of the high dynamic range image shooting method provided by the embodiment of the present invention;

Fig. 2 is the second flowchart of the high dynamic range image shooting method provided by the embodiment of the present invention;

Fig. 3 is the third flowchart of the high dynamic range image shooting method provided by the embodiment of the present invention;

Fig. 4 is one of the structural diagrams of the mobile terminal provided by the embodiment of the present invention;

Fig. 5 is one of the structural diagrams of the area determination module in the mobile terminal provided by the embodiment of the present invention;

Fig. 6 is the second structural diagram of the area determination module in the mobile terminal provided by the embodiment of the present invention;

7 is a structural diagram of a background area determination unit in a mobile terminal provided by an embodiment of the present invention;

FIG. 8 is the second structural diagram of the mobile terminal provided by the embodiment of the present invention;

FIG. 9 is the third structural diagram of the mobile terminal provided by the embodiment of the present invention;

FIG. 10 is a fourth structural diagram of a mobile terminal provided by an embodiment of the present invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are some of the embodiments of the present invention, but not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Referring to Fig. 1, Fig. 1 is one of the flow charts of the high dynamic range image capturing method provided by the embodiment of the present invention, which is applied to a mobile terminal with a first camera and a second camera on one side, as shown in Fig. 1 , the Methods include:

Step 101. Acquire a first preview image captured by a first camera.

In the embodiment of the present invention, if the camera application program of the mobile terminal is started, and the first camera of the mobile terminal is in the image preview state, the mobile terminal can acquire the image captured by the first camera as the first preview image.

Step 102. Determine a foreground image area and a background image area in the first preview image.

In the embodiment of the present invention, when the first preview image is acquired in step 101 above, the mobile terminal may determine the foreground image area and the background image area in the first preview image.

Wherein, the above-mentioned determination of the foreground image area and the background image area in the first preview image may be to use two different pre-designated image areas in the first preview image as the foreground image area and the background image area respectively, for example: it may be pre-designated A certain fixed image area in the first preview image is used as the foreground image area, and the image area other than the foreground image area is used as the background image area; or part of the image area except the foreground image area is used as the background image area, etc.

Step 103. If a photographing instruction is received, respectively acquire a second preview image captured by the first camera and a third preview image captured by the second camera.

In the embodiment of the present invention, if the above-mentioned step 102 determines the foreground image area and the background image area in the first preview image, when the mobile terminal receives a photographing instruction, the mobile terminal can simultaneously control the first camera to capture the second preview image, and the second The second camera captures the third preview image, so that the acquired second preview image and the third preview image are the same frame image, thereby reducing or even avoiding ghosting or afterimage of the synthesized HDR image.

Wherein, the above-mentioned second preview image is an image exposed to the foreground image area, and the above-mentioned third preview image is an image exposed to the background image area, that is, the second preview image is collected by the first camera, and the third preview image is collected by the second camera. , the mobile terminal can control the first camera to expose the captured image with the foreground image area as the reference exposure point, and control the first camera to capture the exposed image as the second preview image; the mobile terminal controls the second camera to The collected image is exposed with the background image area as the reference exposure point, and the second camera is controlled to capture the exposed image as the third preview image, so that the exposure reference points of the second preview image and the third preview image are different, and the synthesis is improved. The quality of the HDR image. Both the above-mentioned first camera and the second camera may use automatic exposure (Automatic Exposure, AE) technology to respectively expose the foreground image area and the background image area.

It should be noted that the above-mentioned first camera and the above-mentioned second camera are arranged on the same side of the mobile terminal. For example, the first camera and the second camera may form a front dual camera or a rear dual camera of the mobile terminal. In addition, in order to ensure that the synthesized HDR image is not distorted, the focal length and field of view of the first camera and the second camera are set to be consistent, so that the size of the image captured by the first camera and the image captured by the second camera and the size of the subject can be adjusted. be consistent.

Step 104: Perform image composition processing on the second preview image and the third preview image to output a high dynamic range image.

In the embodiment of the present invention, if the second preview image and the third preview image are obtained in step 103 above, the mobile terminal can synthesize the second preview image and the third preview image, and the mobile terminal can synthesize the second preview image and the third preview image during the image synthesis process. The preview image and the third preview image are subjected to image registration, exposure synthesis, tone mapping, etc., so as to synthesize a high-quality HDR image.

In the embodiment of the present invention, the mobile terminal can be any mobile terminal with a first camera and a second camera on one side, such as a mobile phone, a tablet computer (Tablet Personal Computer), a laptop computer (LaptopComputer), a personal digital Assistant (personal digital assistant, PDA for short), mobile Internet device (Mobile Internet Device, MID) or wearable device (Wearable Device) and other mobile terminals.

In the embodiment of the present invention, the first preview image collected by the first camera is obtained; the foreground image area and the background image area in the first preview image are determined; The second preview image and the third preview image collected by the second camera; performing image synthesis processing on the second preview image and the third preview image, and outputting a high dynamic range image; wherein, the second preview image is an image exposed to the foreground image area, and the third preview image is an image exposed to the background image area. The mobile terminal can avoid the time difference between photos used for synthesizing the HDR image, thereby reducing the occurrence of ghosting or afterimage, and improving the quality of photos taken by the mobile terminal.

Referring to FIG. 2, FIG. 2 is a flowchart of a high dynamic range image capturing method provided by an embodiment of the present invention. As shown in FIG. 2, the method includes:

Step 201. Acquire a first preview image captured by a first camera.

Step 202: Perform face recognition on the first preview image to obtain a face image area.

In the embodiment of the present invention, if the first preview image is obtained in the above step 201, the mobile terminal can identify the face image in the first preview image through face recognition technology, so as to obtain the face image area, that is, the face image area in the first preview image. The area where the face image is located. Wherein, the aforementioned face recognition technology is well known to those skilled in the art, and will not be repeated here.

Step 203. Determine the face image area as a foreground image area.

In the embodiment of the present invention, if the face image area is obtained in step 202, the mobile terminal may determine the face image area as the foreground image area.

Step 204: Determine a background image area based on the foreground image area.

In the embodiment of the present invention, if the foreground image area is determined in step 203 above, the mobile terminal may determine any area in the first preview image except the face image area as the background image area according to preset rules. For example: in the first preview image, the area other than the face image area can be used as the background image area; or in the image area other than the face image area of the first preview image, a part of the area is randomly determined as the background image area.

Optionally, the above step 204 may include: acquiring a Y-channel image of the first preview image; taking m*n pixel blocks as a unit pixel block, for the Y-channel image except for the foreground image area Image segmentation is performed on all image regions to obtain T pixel blocks; for each pixel block in the T pixel blocks, the brightness and value of all pixels in each pixel block are calculated; the maximum brightness of all brightness and values is summed The image area where the pixel block corresponding to the value is located is determined as the background image area.

In this embodiment, the mobile terminal can divide the image area in the first preview image except the foreground image area into multiple pixel blocks of preset size, and determine the location of the pixel block with the maximum brightness and value among the multiple pixel blocks. The image area is the background image area, so that when the mobile terminal controls the second camera to expose the background image area to obtain the third preset image, the image area where the pixel block with the maximum brightness and value is located is used as the exposure reference point, and the synthetic The exposure effect of the HDR image is better, further improving the quality of the HDR image.

Wherein, the above-mentioned Y-channel image is an image including image data in YUV (“Y” indicates gray value; “U” and “V” indicate chroma) format. Certainly, the above-mentioned first preview image may also be an image including image data in other formats, and the mobile terminal may convert the format of the image data of the first preview image to obtain the Y-channel image of the first preview image, for example: if A preview image is an image including image data in RGB (red, ie Red; green, ie Green; blue, ie Blue) format, and the mobile terminal can convert its image data from RGB format to YUV format, thereby obtaining the first preview image The Y channel image.

Step 205. If a photographing instruction is received, respectively acquire a second preview image captured by the first camera and a third preview image captured by the second camera.

In the embodiment of the present invention, if the above-mentioned step 204 determines the foreground image area and the background image area in the first preview image, when the mobile terminal receives a photographing instruction, the mobile terminal can simultaneously control the first camera to capture the second preview image, and the second The second camera captures the third preview image, so that the acquired second preview image and the third preview image are the same frame image, thereby reducing or even avoiding ghosting or afterimage of the synthesized HDR image.

Optionally, before the above step 205, it may also include: respectively performing light metering on the foreground image area and the background image area to obtain the first exposure value of the foreground image area and the first exposure value of the background image area respectively. Two exposure values; the above step 205 may include: if the first exposure value and the second exposure value are not the same, respectively acquiring the second preview image collected by the first camera and the first preview image collected by the second camera Three preview images.

In this embodiment, when the camera application of the mobile terminal is turned on, and if the foreground image area and the background image area are determined in step 204 above, the mobile terminal can perform light metering on the foreground image area and the background image area of the first preset image, If the exposure values of the foreground image area and the background image area are different, it is determined that the mobile terminal needs to turn on the HDR function when taking pictures. preview the image, and combine the HDR image with the second preview image and the third preview image to improve the quality of the photo taken by the mobile terminal.

It should be noted that if the above-mentioned exposure values of the foreground image area and the background image area are the same, the photos taken by the mobile terminal through a single camera can also have higher image quality, and the mobile terminal can control the first camera to collect images, and the second An image collected by a camera is output as a photo, thereby saving battery power and storage resources of the mobile terminal.

Step 206: Perform image composition processing on the second preview image and the third preview image to output a high dynamic range image.

In the embodiment of the present invention, the face image area is obtained by performing face recognition on the first preview image; the face image area is determined as the foreground image area; and the background image area is determined based on the foreground image area. In this way, when the captured photo includes a face image, the mobile terminal can determine the foreground image area and the background image area through the face image area, which can improve the exposure effect of the synthesized HDR image, thereby improving the image quality of the HDR image.

Referring to FIG. 3, FIG. 3 is a flowchart of a high dynamic range image capturing method provided by an embodiment of the present invention. As shown in FIG. 3, the method includes:

Step 301. Acquire a first preview image captured by a first camera.

Step 302. Obtain depth data of the first preview image, where the depth data includes a depth value of each pixel.

In the embodiment of the present invention, if the first preview image is acquired in step 301 above, the mobile terminal may acquire the depth data of the first preview image. Wherein, the depth data of the above-mentioned first preview image may be each pixel in the first preview image detected by the mobile terminal through a distance detection component on it, such as an infrared emitter, when the first camera captures the first preview image the depth value.

Step 303. Obtain the minimum depth value v ₀ in the depth data.

In the embodiment of the present invention, if the above step 302 obtains the depth data of the first preview image, the mobile terminal can compare the depth values of each pixel in the first preview image, so as to obtain the minimum depth value v in the depth data ₀ .

Step 304. Based on the minimum depth value v ₀ , determine a set of pixel points with a depth value in the range of v ₀ -(v ₀ +v ₁ ) as the foreground image area.

In the embodiment of the present invention, when the first camera captures the first preview image, the closer the subject is to the first camera, the smaller the depth of the pixel corresponding to the subject in the first preview image is. value, and the depth values of each pixel in the image corresponding to the same subject are usually relatively close, the mobile terminal determines the set of pixels with depth values in the range of v ₀ ~ (v ₀ +v ₁ ) as the foreground image area , so that the image area of the image corresponding to the subject close to the first camera in the first preview image can be used as the foreground image area, so that the mobile terminal can select an appropriate foreground image area, so that the exposure effect of the synthesized HDR image can be made better good.

Step 305. Determine a background image area based on the foreground image area.

In the embodiment of the present invention, the above step 304 determines the foreground image area, and the mobile terminal may determine any area in the first preview image except the foreground image area as the background image area according to preset rules.

Optionally, the above step 305 may include: acquiring a Y-channel image of the first preview image; taking m*n pixel blocks as unit pixel blocks, for the Y-channel image except for the foreground image area Image segmentation is performed on all image regions to obtain T pixel blocks; for each pixel block in the T pixel blocks, the brightness and value of all pixels in each pixel block are calculated; the maximum brightness of all brightness and values is summed The image area where the pixel block corresponding to the value is located is determined as the background image area.

In this embodiment, the mobile terminal can divide the image area in the first preview image except the face image area into a plurality of pixel blocks of a preset size, and determine the pixel block with the maximum brightness and value among the plurality of pixel blocks The image area is the background image area, so that when the mobile terminal controls the second camera to expose the background image area to obtain the third preset image, the image area where the pixel block with the maximum brightness and value is located is used as the exposure reference point, which can make The composited HDR image has a better exposure, further improving the quality of the HDR image.

Step 306: If a photographing instruction is received, respectively acquire a second preview image captured by the first camera and a third preview image captured by the second camera.

In the embodiment of the present invention, if the above-mentioned step 305 determines the foreground image area and the background image area in the first preview image, when the mobile terminal receives a photographing instruction, the mobile terminal can simultaneously control the first camera to capture the second preview image, and the second The second camera captures the third preview image, so that the acquired second preview image and the third preview image are the same frame image, thereby reducing or even avoiding ghosting or afterimage of the synthesized HDR image.

Optionally, before the above step 306, it may also include: respectively performing light metering on the foreground image area and the background image area to obtain the first exposure value of the foreground image area and the first exposure value of the background image area respectively. Two exposure values; the above step 306 may include: if the first exposure value and the second exposure value are not the same, respectively acquiring the second preview image collected by the first camera and the first preview image collected by the second camera Three preview images, so that the mobile terminal can automatically turn on the HDR function in time, improve the quality of photos taken by the mobile terminal, and avoid wasting battery power and storage resources.

Step 307: Perform image composition processing on the second preview image and the third preview image to output a high dynamic range image.

In the embodiment of the present invention, by acquiring the depth data of the first preview image, the depth data includes the depth value of each pixel; acquiring the minimum depth value v ₀ in the depth data; based on the minimum depth value v ₀ , determining a set of pixel points whose depth values are in the range of v ₀ to (v ₀ +v ₁ ) as a foreground image area; based on the foreground image area, determining a background image area. In this way, the mobile terminal can determine the foreground image area and the background image area according to the depth data of the image, so as to respectively expose the images collected by the first camera and the second camera according to the foreground image area and the background image area, and improve the quality of the synthesized HDR image. Exposure effect to enhance the image quality of HDR images.

Referring to FIG. 4, FIG. 4 is a structural diagram of a mobile terminal provided by the implementation of the present invention. A first camera and a second camera are arranged on one side of the mobile terminal 400. As shown in FIG. 4, the mobile terminal 400 includes sequentially connected The first image acquisition module 401, the region determination module 402, the second image acquisition module 403, and the synthesis module 404 of:

The first image acquisition module 401 is configured to acquire a first preview image captured by the first camera;

an area determination module 402, configured to determine the foreground image area and the background image area in the first preview image acquired by the first image acquisition module 401;

The second image acquiring module 403 is configured to acquire a second preview image captured by the first camera and a third preview image captured by the second camera respectively if a photographing instruction is received;

A synthesis module 404, configured to perform image synthesis processing on the second preview image and the third preview image acquired by the second image acquisition module, and output a high dynamic range image;

Wherein, the second preview image is an image exposed to the foreground image area determined by the area determining module 402 , and the third preview image is an image exposed to the background image area determined by the area determining module 402 .

Optionally, as shown in FIG. 5, the area determining module 402 may include:

A face recognition unit 4021, configured to perform face recognition on the first preview image acquired by the first image acquisition module 401, to obtain a face image area;

The first foreground area determination unit 4022 is configured to determine the face image area identified by the face recognition unit 4021 as the foreground image area;

A background area determining unit 4023, configured to determine a background image area based on the foreground image area determined by the first foreground area determining unit 4022.

Optionally, as shown in FIG. 6, the area determining module 402 may include:

A depth data acquisition unit 4024, configured to acquire the depth data of the first preview image acquired by the first image acquisition module 401, the depth data including the depth value of each pixel;

A minimum depth value acquisition unit 4025, configured to acquire the minimum depth value v0 in the depth data acquired by the depth data acquisition unit 4024;

The second foreground area determination unit 4026 is configured to, based on the minimum depth value v ₀ acquired by the minimum depth value acquisition unit 4025, set a set of pixel points whose depth values are within the range of v ₀ -(v ₀ +v ₁ ) Determined as the foreground image area;

A background area determining unit 4027, configured to determine a background image area based on the foreground image area determined by the second foreground area determining unit 4026;

Wherein, v1 is a preset threshold.

Optionally, as shown in FIG. 7, the background area determining unit 4027 may include:

The Y-channel image acquisition subunit 40271 is configured to acquire the Y-channel image of the first preview image acquired by the first image acquisition module 401;

The pixel block segmentation sub-unit 40272 is used to use m*n pixel blocks as unit pixel blocks to perform all image regions in the Y-channel image obtained by the Y-channel image acquisition sub-unit 40271 except the foreground image region Segment the image to obtain T pixel blocks;

Brightness and value calculation subunit 40273, for calculating the brightness and value of all pixel points in each pixel block for each pixel block in the T pixel blocks obtained by the pixel block division subunit 40272;

The background area determination subunit 40274 is configured to determine the image area where the pixel block corresponding to the maximum brightness sum value among all the brightness sum values calculated by the brightness sum value calculation subunit 40273 is located as the background image area.

Optionally, as shown in FIG. 8, the mobile terminal 400 may further include:

A light metering module 405, configured to perform light metering on the foreground image area and the background image area determined by the area determining module 402, respectively to obtain a first exposure value of the foreground image area and a second exposure value of the background image area value;

The second image acquiring module 403 is further configured to acquire the second preview image captured by the first camera and the The third preview image captured by the second camera.

The mobile terminal 400 can implement various processes implemented by the mobile terminal in the embodiments in FIG. 1 to FIG. 3 , and details are not repeated here to avoid repetition.

The mobile terminal 400 of the embodiment of the present invention acquires the first preview image collected by the first camera; determines the foreground image area and the background image area in the first preview image; The second preview image collected by the camera and the third preview image collected by the second camera; performing image synthesis processing on the second preview image and the third preview image, and outputting a high dynamic range image; wherein, the first The second preview image is an image exposed to the foreground image area, and the third preview image is an image exposed to the background image area. The mobile terminal can avoid the time difference between photos used for synthesizing the HDR image, thereby reducing the occurrence of ghosting or afterimage, and improving the quality of photos taken by the mobile terminal.

An embodiment of the present invention also provides a mobile terminal, including a processor, a memory, and a computer program stored in the memory and operable on the processor. When the computer program is executed by the processor, the above-mentioned advanced The various processes of the embodiments of the dynamic range image capture method can achieve the same technical effect, so in order to avoid repetition, details will not be repeated here.

An embodiment of the present invention also provides a computer-readable storage medium, on which a computer program is stored, and when the computer program is executed by a processor, each process of the above-mentioned high dynamic range image capture method embodiment is implemented, and can To achieve the same technical effect, in order to avoid repetition, no more details are given here. Wherein, the computer-readable storage medium is, for example, a read-only memory (Read-Only Memory, ROM for short), a random access memory (Random Access Memory, RAM for short), a magnetic disk or an optical disk, and the like.

Referring to FIG. 9, FIG. 9 is a structural diagram of a mobile terminal provided by the present invention. As shown in FIG. Various components in the mobile terminal 900 are coupled together through a bus system 905 . It can be understood that the bus system 905 is used to realize connection and communication between these components. In addition to the data bus, the bus system 905 also includes a power bus, a control bus and a status signal bus. However, for the sake of clarity, various buses are marked as bus system 905 in FIG. It is connected with various components of the mobile terminal through the bus system 905 .

Wherein, the user interface 903 may include a display, a keyboard, or a pointing device (for example, a mouse, a trackball (trackball), a touch panel, or a touch screen, and the like.

It can be understood that the memory 902 in this embodiment of the present invention may be a volatile memory or a nonvolatile memory, or may include both volatile and nonvolatile memories. Wherein, the non-volatile memory may be a read-only memory (Read-Only Memory, ROM), a programmable read-only memory (Programmable ROM, PROM), an erasable programmable read-only memory (Erasable PROM, EPROM), an electronically programmable Erase Programmable Read-Only Memory (Electrically EPROM, EEPROM) or Flash. The volatile memory can be Random Access Memory (RAM), which acts as an external cache. By way of illustration and not limitation, many forms of RAM are available such as Static RAM (SRAM), Dynamic RAM (DRAM), Synchronous DRAM (Synchronous DRAM, SDRAM), double data rate synchronous dynamic random access memory (Double Data RateSDRAM, DDRSDRAM), enhanced synchronous dynamic random access memory (Enhanced SDRAM, ESDRAM), synchronous connection dynamic random access memory (Synchlink DRAM, SLDRAM) and Direct memory bus random access memory (DirectRambus RAM, DRRAM). Memory 902 of the systems and methods described herein is intended to include, but is not limited to, these and any other suitable types of memory.

In some implementations, the memory 902 stores the following elements, executable modules or data structures, or their subsets, or their extended sets: an operating system 9021 and an application program 9022 .

Among them, the operating system 9021 includes various system programs, such as framework layer, core library layer, driver layer, etc., for realizing various basic services and processing hardware-based tasks. The application program 9022 includes various application programs, such as a media player (Media Player), a browser (Browser), etc., and is used to implement various application services. The program for realizing the method of the embodiment of the present invention may be included in the application program 9022 .

In the embodiment of the present invention, the mobile terminal 900 further includes: a computer program stored in the memory 902 and operable on the processor 901, specifically, it may be a computer program in the application program 9022, and the computer program is executed by the processor 901 When implementing the following steps: obtain the first preview image collected by the first camera; determine the foreground image area and the background image area in the first preview image; if a photographing instruction is received, obtain the first preview image collected by the first camera Two preview images and the third preview image collected by the second camera; performing image synthesis processing on the second preview image and the third preview image, and outputting a high dynamic range image; wherein the second preview image is An image exposed to the foreground image area, and the third preview image is an image exposed to the background image area.

The methods disclosed in the foregoing embodiments of the present invention may be applied to the processor 901 or implemented by the processor 901 . The processor 901 may be an integrated circuit chip with signal processing capabilities. In the implementation process, each step of the above method may be completed by an integrated logic circuit of hardware in the processor 901 or instructions in the form of software. The aforementioned processor 901 may be a general-purpose processor, a digital signal processor (Digital Signal Processor, DSP), an application specific integrated circuit (Application Specific Integrated Circuit, ASIC), an off-the-shelf programmable gate array (Field Programmable Gate Array, FPGA) or other available Program logic devices, discrete gate or transistor logic devices, discrete hardware components. Various methods, steps and logic block diagrams disclosed in the embodiments of the present invention may be implemented or executed. A general-purpose processor may be a microprocessor, or the processor may be any conventional processor, or the like. The steps of the methods disclosed in the embodiments of the present invention may be directly implemented by a hardware decoding processor, or implemented by a combination of hardware and software modules in the decoding processor. The software module may be located in a computer-readable storage medium mature in the field such as random access memory, flash memory, read-only memory, programmable read-only memory or electrically erasable programmable memory, registers, and the like. The computer-readable storage medium is located in the memory 902, and the processor 901 reads the information in the memory 902, and completes the steps of the above method in combination with its hardware. Specifically, a computer program is stored on the computer-readable storage medium, and when the computer program is executed by the processor 901, various steps in the above-mentioned embodiments of the high dynamic range image capturing method are implemented.

It should be understood that the embodiments described herein may be implemented by hardware, software, firmware, middleware, microcode or a combination thereof. For hardware implementation, the processing unit can be implemented in one or more application specific integrated circuits (Application Specific Integrated Circuits, ASIC), digital signal processor (Digital Signal Processing, DSP), digital signal processing device (DSP Device, DSPD), programmable logic Device (Programmable Logic Device, PLD), Field-Programmable Gate Array (Field-Programmable Gate Array, FPGA), general-purpose processor, controller, microcontroller, microprocessor, other electronic units for performing the functions described in this application or a combination thereof.

For a software implementation, the techniques described herein can be implemented through modules (eg, procedures, functions, and so on) that perform the functions described herein. Software codes can be stored in memory and executed by a processor. Memory can be implemented within the processor or external to the processor.

Optionally, when the computer program is executed by the processor 901, the following steps can also be implemented: performing face recognition on the first preview image to obtain a face image area; determining the face image area as a foreground image area; The foreground image area determines the background image area.

Optionally, when the computer program is executed by the processor 901, the following steps may also be implemented: acquiring the depth data of the first preview image, the depth data including the depth value of each pixel; acquiring the minimum depth value in the depth data. Depth value v ₀ ; based on the minimum depth value v ₀ , determining a set of pixels whose depth values are in the range of v ₀ ~ (v ₀ +v ₁ ) as the foreground image area; based on the foreground image area, Determine the background image area; wherein, v ₁ is a preset threshold.

Optionally, when the computer program is executed by the processor 901, the following steps can also be implemented: acquiring the Y channel image of the first preview image; taking m*n pixel blocks as unit pixel blocks, dividing the Y channel image from All image areas outside the foreground image area are image-segmented to obtain T pixel blocks; for each pixel block in the T pixel blocks, the brightness and value of all pixels in each pixel block are calculated; all The image region where the pixel block corresponding to the maximum brightness and value in the brightness and value is located is determined as the background image region.

Optionally, when the computer program is executed by the processor 901, the following steps can also be implemented: separately measure the light of the foreground image area and the background image area, and respectively obtain the first exposure value of the foreground image area and the first exposure value of the foreground image area. The second exposure value of the background image area; if the first exposure value and the second exposure value are not the same, obtain the second preview image collected by the first camera and the third preview image collected by the second camera respectively. Preview image.

The mobile terminal 900 can implement various processes implemented by the mobile terminal in the foregoing embodiments, and to avoid repetition, details are not repeated here.

The mobile terminal 900 in the embodiment of the present invention acquires the first preview image collected by the first camera; determines the foreground image area and the background image area in the first preview image; The second preview image collected by the camera and the third preview image collected by the second camera; performing image synthesis processing on the second preview image and the third preview image, and outputting a high dynamic range image; wherein, the first The second preview image is an image exposed to the foreground image area, and the third preview image is an image exposed to the background image area. The mobile terminal can avoid the time difference between photos used for synthesizing the HDR image, thereby reducing the occurrence of ghosting or afterimage, and improving the quality of photos taken by the mobile terminal.

Please refer to FIG. 10 . FIG. 10 is a structural diagram of a mobile terminal provided by the implementation of the present invention, which can realize the details of the high dynamic range image capturing method in the embodiment in FIG. 1 to FIG. 3 and achieve the same effect. As shown in Figure 10, the mobile terminal 1000 includes a radio frequency (Radio Frequency, RF) circuit 1010, a memory 1020, an input unit 1030, a display unit 1040, a processor 1050, an audio circuit 1060, a communication module 1070, a power supply 1080, and a first camera 1090 The first camera 1090 and the second camera 1100 are disposed on the same side of the mobile terminal 1000 as the second camera 1100 .

Wherein, the input unit 1030 can be used for receiving number or character information input by the user, and generating signal input related to the user setting and function control of the mobile terminal 1000 . Specifically, in the embodiment of the present invention, the input unit 1030 may include a touch panel 1031 . The touch panel 1031, also referred to as a touch screen, can collect user's touch operations on or near it (such as the user's operation on the touch panel 1031 using any suitable object or accessory such as a finger, a stylus), and The specified program drives the corresponding connected device. Optionally, the touch panel 1031 may include two parts, a touch detection device and a touch controller. Among them, the touch detection device detects the user's touch orientation, and detects the signal brought by the touch operation, and transmits the signal to the touch controller; the touch controller receives the touch information from the touch detection device, converts it into contact coordinates, and sends it to the to the processor 1050, and can receive and execute commands sent by the processor 1050. In addition, the touch panel 1031 can be implemented in various types such as resistive, capacitive, infrared, and surface acoustic wave. In addition to the touch panel 1031, the input unit 1030 may also include other input devices 1032, which may include but not limited to physical keyboards, function keys (such as volume control buttons, switch buttons, etc.), trackballs, mice, joysticks, etc. one or more of.

Wherein, the display unit 1040 can be used to display information input by the user or information provided to the user and various menu interfaces of the mobile terminal 1000 . The display unit 1040 may include a display panel 1041, and optionally, the display panel 1041 may be configured in the form of an LCD or an organic light-emitting diode (Organic Light-Emitting Diode, OLED).

It should be noted that the touch panel 1031 can cover the display panel 1041 to form a touch display screen. When the touch display screen detects a touch operation on or near it, it is sent to the processor 1050 to determine the type of the touch event, and then the processor 1050 provides corresponding visual output on the touch display screen according to the type of the touch event.

The touch display screen includes an application program interface display area and a common control display area. The arrangement of the display area of the application program interface and the display area of the commonly used controls is not limited, and may be an arrangement in which the two display areas can be distinguished, such as vertical arrangement, left-right arrangement, and the like. The application program interface display area can be used to display the interface of the application program. Each interface may include at least one interface element such as an icon of an application program and/or a widget desktop control. The application program interface display area can also be an empty interface without any content. The commonly used control display area is used to display controls with a high usage rate, for example, application icons such as setting buttons, interface numbers, scroll bars, and phonebook icons. The touch screen in the embodiment of the present invention is a flexible screen, and both sides of the flexible screen are pasted with an organic transparent conductive film of carbon nanotubes.

Wherein the processor 1050 is the control center of the mobile terminal 1000, utilizes various interfaces and lines to connect various parts of the whole mobile phone, runs or executes the software programs and/or modules stored in the first memory 1021, and calls the software programs and/or modules stored in the second memory 1021. The data in the memory 1022 executes various functions of the mobile terminal 1000 and processes data, so as to monitor the mobile terminal 1000 as a whole. Optionally, the processor 1050 may include one or more processing units.

In the embodiment of the present invention, the mobile terminal further includes: a computer program stored in the first memory 1021 and operable on the processor 1050. When the computer program is executed by the processor 1050, the following steps are implemented: acquiring the first preview image; determine the foreground image area and the background image area in the first preview image; if a photographing instruction is received, obtain the second preview image captured by the first camera and the third image captured by the second camera respectively preview image; perform image synthesis processing on the second preview image and the third preview image, and output a high dynamic range image; wherein, the second preview image is an image exposed to the foreground image area, and the first preview image is The three preview images are images exposed to the background image area.

Optionally, when the computer program is executed by the processor 1050, the following steps can also be implemented: performing face recognition on the first preview image to obtain a face image area; determining the face image area as a foreground image area; The foreground image area determines the background image area.

Optionally, when the computer program is executed by the processor 1050, the following steps may also be implemented: acquiring the depth data of the first preview image, the depth data including the depth value of each pixel; acquiring the minimum depth value in the depth data. Depth value v ₀ ; based on the minimum depth value v ₀ , determining a set of pixels whose depth values are in the range of v ₀ ~ (v ₀ +v ₁ ) as the foreground image area; based on the foreground image area, Determine the background image area; wherein, v1 is a preset threshold.

Optionally, when the computer program is executed by the processor 1050, the following steps can also be implemented: acquiring the Y-channel image of the first preview image; taking m*n pixel blocks as unit pixel blocks, dividing the Y-channel image All image areas outside the foreground image area are image-segmented to obtain T pixel blocks; for each pixel block in the T pixel blocks, the brightness and value of all pixels in each pixel block are calculated; all The image region where the pixel block corresponding to the maximum brightness and value in the brightness and value is located is determined as the background image region.

Optionally, when the computer program is executed by the processor 1050, the following steps can also be implemented: separately measure the light of the foreground image area and the background image area, and respectively obtain the first exposure value of the foreground image area and the first exposure value of the foreground image area. The second exposure value of the background image area; if the first exposure value and the second exposure value are not the same, obtain the second preview image collected by the first camera and the third preview image collected by the second camera respectively. Preview image.

The mobile terminal 1000 can implement various processes implemented by the mobile terminal in the foregoing embodiments, and to avoid repetition, details are not repeated here.

The mobile terminal 1000 of the embodiment of the present invention acquires the first preview image captured by the first camera; determines the foreground image area and the background image area in the first preview image; The second preview image collected by the camera and the third preview image collected by the second camera; performing image synthesis processing on the second preview image and the third preview image, and outputting a high dynamic range image; wherein, the first The second preview image is an image exposed to the foreground image area, and the third preview image is an image exposed to the background image area. The mobile terminal can avoid the time difference between photos used for synthesizing the HDR image, thereby reducing the occurrence of ghosting or afterimage, and improving the quality of photos taken by the mobile terminal.

Those skilled in the art can appreciate that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Skilled artisans may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of the present invention.

Those skilled in the art can clearly understand that for the convenience and brevity of the description, the specific working process of the above-described system, mobile terminal and unit can refer to the corresponding process in the foregoing method embodiments, which will not be repeated here.

In the embodiments provided in this application, it should be understood that the disclosed mobile terminal and method can be implemented in other ways. For example, the mobile terminal embodiments described above are only illustrative. For example, the division of units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or can be Integrate into another system, or some features may be ignored, or not implemented. In another point, the mutual coupling or direct coupling or communication connection shown or discussed may be through some interfaces, and the indirect coupling or communication connection of mobile terminals or units may be in electrical, mechanical or other forms.

A unit described as a separate component may or may not be physically separated, and a component displayed as a unit may or may not be a physical unit, that is, it may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment of the present invention.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, each unit may exist separately physically, or two or more units may be integrated into one unit.

If the functions are realized in the form of software functional units and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on this understanding, the essence of the technical solution of the present invention or the part that contributes to the prior art or the part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including Several instructions are used to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods in various embodiments of the present invention. The aforementioned storage medium includes: various media capable of storing program codes such as U disk, mobile hard disk, ROM, RAM, magnetic disk or optical disk.

The above is only a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Anyone familiar with the technical field can easily think of changes or replacements within the technical scope disclosed in the present invention, and should cover all Within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (12)

1. a kind of high dynamic range images image pickup method, applied to the unilateral movement for being provided with the first camera and second camera Terminal, it is characterised in that methods described includes：

Obtain the first preview image of the first camera collection；

Determine the foreground image areas and background image region in first preview image；

If receiving photographing instruction, the second preview image of the first camera collection and second shooting are obtained respectively 3rd preview image of head collection；

Image synthesis processing is carried out to second preview image and the 3rd preview image, high dynamic range images are exported；

Wherein, second preview image be to the foreground image areas expose image, the 3rd preview image for pair The image of the background image region exposure.

2. high dynamic range images image pickup method according to claim 1, it is characterised in that the determination described first is pre- Look at foreground image areas and background image region in image the step of, including：

Recognition of face is carried out to first preview image, facial image region is obtained；

The facial image region is defined as foreground image areas；

Based on the foreground image areas, background image region is determined.

3. high dynamic range images image pickup method according to claim 1, it is characterised in that the determination described first is pre- Look at foreground image areas and background image region in image the step of, including：

The depth data of first preview image is obtained, the depth data includes the depth value of each pixel；

Obtain the minimum depth value v in the depth data₀；

Based on the minimum depth value v₀, by depth value value in v₀~(v₀+v₁) in the range of pixel set be defined as before Scape image-region；

Based on the foreground image areas, background image region is determined；

Wherein, v₁For default threshold value.

4. the high dynamic range images image pickup method according to Claims 2 or 3, it is characterised in that described based on before described Scape image-region, the step of determining background image region, including：

Obtain the Y channel images of first preview image；

Using m*n block of pixels as unit block of pixels, to all figures in the Y channel images in addition to the foreground image areas As region carries out image segmentation, T block of pixels is obtained；

For each block of pixels in the T block of pixels, the brightness of all pixels point and value in each block of pixels are calculated；

Image-region where the corresponding block of pixels of high-high brightness and value in all brightness and value is defined as background image region.

5. high dynamic range images image pickup method according to any one of claim 1 to 3, it is characterised in that described point The step of the second preview image of the first camera collection and the 3rd preview image of second camera collection is not obtained Before rapid, in addition to：

Light-metering is carried out respectively to the foreground image areas and the background image region, the foreground image areas is respectively obtained The first exposure value and the background image region the second exposure value；

The 3rd of second preview image for obtaining first camera collection respectively and second camera collection is pre- Look at image the step of, including：

If first exposure value and second exposure value are differed, the second of the first camera collection is obtained respectively Preview image and the 3rd preview image of second camera collection.

6. a kind of mobile terminal, the one side of the mobile terminal is provided with the first camera and second camera, it is characterised in that The mobile terminal also includes：

First image collection module, the first preview image for obtaining the collection of the first camera；

Area determination module, for determining the foreground image area in the first preview image that described first image acquisition module is obtained Domain and background image region；

Second image collection module, if for receiving photographing instruction, the second of the first camera collection is obtained respectively Preview image and the 3rd preview image of second camera collection；

Synthesis module, the second preview image and the 3rd preview image for being obtained to second image collection module are schemed As synthesis processing, high dynamic range images are exported；

Wherein, second preview image is the image of the foreground image areas exposure determined to the area determination module, institute State the image that the 3rd preview image is the background image region exposure determined to the area determination module.

7. mobile terminal according to claim 6, it is characterised in that the area determination module includes：

Face identification unit, the first preview image for being obtained to described first image acquisition module carries out recognition of face, obtains To facial image region；

First foreground area determining unit, the facial image region for the face identification unit to be recognized is defined as foreground picture As region；

Background area determining unit, for the foreground image areas determined based on the first foreground area determining unit, it is determined that Background image region.

8. mobile terminal according to claim 6, it is characterised in that the area determination module includes：

Depth data acquiring unit, the depth number of the first preview image for obtaining the acquisition of described first image acquisition module According to the depth data includes the depth value of each pixel；

Minimum depth value acquiring unit, for obtaining the minimum-depth in the depth data that the depth data acquiring unit is obtained Value v₀；

Second foreground area determining unit, for the minimum depth value v obtained based on the minimum depth value acquiring unit₀, will be deep Angle value value is in v₀~(v₀+v₁) in the range of the set of pixel be defined as foreground image areas；

Background area determining unit, for the foreground image areas determined based on the second foreground area determining unit, it is determined that Background image region；

Wherein, v₁For default threshold value.

9. the mobile terminal according to claim 7 or 8, it is characterised in that the background area determining unit includes：

Y channel images obtain subelement, the Y passages of the first preview image for obtaining the acquisition of described first image acquisition module Image；

Block of pixels splits subelement, for using m*n block of pixels as unit block of pixels, subelement to be obtained to the Y channel images All image-regions in the Y channel images of acquisition in addition to the foreground image areas carry out image segmentation, obtain T pixel Block；

Brightness and value computation subunit, for splitting each pixel in the T block of pixels that subelement is obtained for the block of pixels Block, calculates the brightness of all pixels point and value in each block of pixels；

Background area determination subelement, for the brightness and value computation subunit to be calculated in obtained all brightness and value Image-region where high-high brightness and the corresponding block of pixels of value is defined as background image region.

10. the mobile terminal according to any one of claim 6 to 8, it is characterised in that the mobile terminal also includes：

Light-metering module, foreground image areas and background image region for being determined to the area determination module are surveyed respectively Light, respectively obtains the first exposure value of the foreground image areas and the second exposure value of the background image region；

If second image collection module is additionally operable to the first exposure value and the second exposure value that the light-metering module measurement is obtained Differ, then obtain respectively first camera collection the second preview image and second camera collection it is the 3rd pre- Look at image.

11. a kind of mobile terminal, the one side of the mobile terminal is provided with the first camera and second camera, its feature exists In the mobile terminal also includes processor, and memory is stored on the memory and can run on the processor Computer program, the computer program is by height of the realization as any one of claim 1 to 5 during the computing device The step of dynamic image image pickup method.

12. a kind of computer-readable recording medium, it is characterised in that be stored with computer on the computer-readable recording medium Program, realizes the HDR figure as any one of claim 1 to 5 when the computer program is executed by processor As the step of image pickup method.