JP2018195938A - Imaging apparatus, control method of imaging apparatus, and program - Google Patents

Abstract

To provide a control technology which allows for photographing reflecting image quality adjustment based on user operation, while performing the photographing easily with image quality setting optimum for a photographic scene by scene discrimination processing.SOLUTION: An imaging apparatus includes scene discrimination means for discriminating a photographic scene, and performing image processing according to discrimination results for a captured image (step S700), image quality adjustment means adjusting the image quality for the captured image according to image quality parameter setting by user operation (step S701), and control means for determining whether or not the discrimination results are changed, and at least a part of the processing by the scene discrimination means is limited, based on the discrimination results and the inputted image quality parameters, when the image quality parameter setting by user operation is inputted (step S702), and executing the processing according to the discrimination results (steps S703-S705).SELECTED DRAWING: Figure 7

Description

  The present invention relates to an imaging device such as a digital camera having a scene discrimination function that analyzes a shooting scene and automatically sets optimal shooting conditions and effects according to the analysis result, a control method for the imaging device, and a program.

  An imaging apparatus such as a digital camera has been proposed that has an auto scene discrimination function in which a camera automatically analyzes a shooting scene and sets optimal shooting conditions and effects according to the analysis result.

  A camera having an auto scene discrimination function automatically selects optimum settings for each scene without the user being aware of shooting conditions such as aperture and shutter speed, and image quality parameters such as contrast and color. Therefore, the user can easily obtain a good image simply by pointing the camera at the subject to be photographed and pressing the shutter button. In general, in the auto scene discrimination mode, the shooting scene recognized by the camera is displayed on a live image with an icon or the like and presented to the user, so the user can optimize various settings for each shooting scene. You can explicitly get a sense of security.

  On the other hand, in the auto scene discrimination mode, the camera automatically determines the image quality, and thus there is a problem that the user cannot enjoy his / her favorite picture creation. Therefore, in recent years, a digital camera has been proposed in which the user can arbitrarily change some image quality parameters even in the auto scene discrimination mode.

  However, if both the auto scene discrimination function and the image quality adjustment by the user are made compatible, the effect selected by the scene discrimination function and the image processing effect set by the user may be inconsistent.

  In order to solve such a problem, a technique for limiting the range of image quality parameters that can be set by the user according to the scene discrimination result has been proposed (Patent Document 1).

U.S. Pat. No. 8,817,157

  However, as in Patent Document 1, if the range of image quality parameters that can be set by the user is limited according to the scene determination result, there is a problem that the range in which the user can make a picture is limited.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a control technique capable of performing shooting that reflects image quality adjustment based on a user operation while performing shooting with an optimal image quality setting for a shooting scene by scene discrimination processing. To do.

  In order to achieve the above object, the imaging apparatus of the present invention automatically determines a shooting scene, controls the imaging apparatus so that an effect according to the determination result is given to the shot image, and the effect is given. An image pickup apparatus including a control unit that displays live captured images, and includes an adjustment unit that accepts a user operation for adjusting the image quality of the displayed captured image, wherein the control unit updates the determination of the shooting scene. According to the adjustment contents by the adjustment means, the control is performed by limiting the photographing scene discrimination processing.

  According to the present invention, it is possible to perform shooting that reflects image quality adjustment based on a user operation while performing shooting with an image quality setting that is optimal for a shooting scene by scene determination processing.

1 is a block diagram illustrating a system configuration example of a digital camera which is a first embodiment of an imaging apparatus of the present invention. It is a figure which shows the relationship between the icon image displayed on the live screen of a display part according to the kind of scene mode and each scene mode, and the image processing effect with respect to each scene mode. It is a flowchart explaining the scene discrimination | determination process for classifying into each scene mode shown in FIG. It is a figure which shows an example of a hue histogram. It is a figure which shows an example of the image quality adjustment screen displayed on a display part. (A) is a figure which shows an example of an aperture value change screen, (b) is a figure which shows an example of a saturation change screen. It is a flowchart explaining the process which makes a scene discrimination | determination process and the image adjustment process based on user operation compatible. It is a figure which shows an example of an effect competition determination process. It is a figure which shows an example of an effect competition determination process. It is a figure which shows the other example of an effect competition determination process. It is a figure which shows the other example of an effect competition determination process. It is a flowchart explaining the process which makes a scene discrimination | determination process and the image adjustment process based on user operation compatible in the digital camera which is 2nd Embodiment of the imaging device of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(First embodiment)
FIG. 1 is a block diagram illustrating a system configuration example of a digital camera which is a first embodiment of an imaging apparatus of the present invention.

  In FIG. 1, a photographing optical system 1 is a photographing optical system including a plurality of lens groups and a diaphragm mechanism, and includes a plurality of lenses including a zoom lens 1a and a focus lens 1b and a diaphragm mechanism 1c. The image pickup device 2 includes a CCD sensor, a CMOS sensor, and the like, and includes an A / D converter that converts an analog signal into a digital signal. The sensor surface of the image pickup device 2 is covered with an RGB color filter such as a Bayer array, for example, so that color photographing is possible.

  When the subject image that has passed through the photographing optical system 1 is formed on the imaging surface of the image sensor 2, image data (image signal) is generated and stored in the memory 3. The memory 3 can hold an image signal A / D converted by the image sensor 2 and data necessary for general processing of the camera.

  The image processing circuit 4 performs image processing and determination processing for an auto scene discrimination function in addition to signal processing such as predetermined pixel interpolation processing, color conversion processing, and noise reduction processing on the image signal held in the memory 3. Bear. The image processing circuit 4 performs predetermined calculation processing using image data captured during shooting standby, sequentially determines shooting conditions based on the obtained calculation results, and notifies the system control unit 5 of the shooting conditions. To do.

  The system control unit 5 includes a ROM, a RAM, a CPU, and the like, and controls the entire camera. For example, the system control unit 5 controls the shutter speed, the aperture mechanism, the focus lens 1b, and the zoom lens 1a in order to perform shooting under the shooting conditions determined by the image processing circuit 4. Then, the system control unit 5 instructs the exposure amount control unit 6, the focus lens control unit 7, and the focal length control unit 8. Further, the system control unit 5 performs image stabilization control using the analysis result of the image processing circuit 4 based on the output signal from the gyro (angular velocity) sensor 13.

  The exposure amount control unit 6 adjusts the exposure time and the photographing sensitivity of the aperture mechanism 1c of the photographing optical system 1 and the image sensor 2, and performs appropriate exposure amount control. The focus lens control unit 7 controls driving of the focus lens 1 b of the photographing optical system 1. The focal length control unit 8 controls the driving of the zoom lens 1 a of the photographing optical system 1 and changes the focal length according to an instruction from the system control unit 5.

  The compression / decompression circuit 9 has a function of compressing still images according to the JPEG format, and a function of compressing moving images according to a compression algorithm typified by H.264 / AVC, and converting them into MPEG, MOV files, and the like. The still image or moving image generated by the compression / decompression circuit 9 is recorded on the recording medium 10. The compression / decompression circuit 9 conversely decompresses the compressed moving image data recorded on the recording medium 10 and stores it in the memory 3 when displaying a captured still image or moving image. An image is displayed on the unit 11.

  The display unit 11 includes an LCD built in the camera, various external monitors, and the like, and displays an image. The operation member 12 is a member that accepts user input, and accepts key input from various buttons provided on the camera and user operation from a touch panel or the like provided in the display unit 11. In accordance with the user operation received by the operation member 12, the system control unit 5 determines or changes the operation of the camera.

  Next, an example of a scene determination process performed by the system control unit 5 will be described with reference to FIGS.

  In general scene discrimination processing, while waiting for shooting, image data that has passed through the shooting optical system 1 and received by the image sensor 2 is analyzed by the image processing circuit 4, and several current shooting scenes are determined in advance. The scene mode is classified.

  FIG. 2 is a diagram showing the relationship between the type of scene mode and the icon image displayed on the live screen of the display unit 11 according to each scene mode and the image processing effect for each scene mode.

  FIG. 3 is a flowchart for explaining scene discrimination processing for classifying each scene mode shown in FIG. Each process of FIG. 3 is executed by the CPU or the like by developing a program stored in the ROM or the like of the system control unit 5 in the RAM.

  In FIG. 3, in step S300, if a face having a size larger than a predetermined size is detected in the captured image, the system control unit 5 classifies the current captured scene as a “person” scene, and proceeds to step S301. Here, for details of the face detection algorithm, there are known methods for detecting a plurality of feature points from an image and discriminating an area considered to be a person's face from the positional relationship between the feature points and the luminance information of the feature point areas. Conceivable.

  In step S <b> 301, the system control unit 5 determines whether or not the subject to be photographed currently exists at a close distance (macro region) based on the focus lens position determined by the focus lens control unit 7. Then, when the focus lens 1b is in focus on the close subject, the system control unit 5 classifies the current shooting scene as a “macro” scene, and proceeds to step S302.

  In step S302, the system control unit 5 uses the exposure amount control unit 6 to adjust the exposure amount control information and image data in which the aperture, shutter speed, and sensitivity of the image sensor 2 are adjusted so that the subject can be photographed with appropriate brightness. Based on the signal amount (brightness), the incident light quantity of the shooting scene is determined. If the system control unit 5 determines that the scene has an incident light amount smaller (darker) than the predetermined amount, the system control unit 5 classifies the current scene as a “night scene” scene, and proceeds to step S303.

  In step S303, the system control unit 5 receives the light with the imaging device 2, classifies the image data held in the memory 3 into a plurality of small regions (areas), and calculates the following equation from the average RGB value in each area: The hue (Hue) is calculated using (1), and is set as a representative hue of the block. The following expression (1) is a general expression for calculating the hue H from the RGB values, and takes a value of 0 to 360, where MAX is the maximum value and MIN is the minimum value of RGB. However, it is not defined when MIN = MAX.

  Similarly, the system control unit 5 obtains the hues of all the areas and generates a hue histogram as shown in FIG.

  Then, the system control unit 5 obtains the sum of the histograms of the blue sky region (B) from the histogram of FIG. 4, and when the sum of the obtained histograms occupies N% or more of the whole histogram, the current shooting scene is “blue sky”. Classify into scenes. Similarly, the system control unit 5 obtains the sum of the histograms of the sunset scene area (A) from the histogram of FIG. 4, and when the sum of the obtained histograms occupies M% or more of the entire histogram, Classify as “Evening Scene”.

  In this way, the system control unit 5 discriminates and classifies the current scene as one of the scene modes in FIG. 2, and also determines image processing parameters and exposure amount control unit 6 in the image processing circuit 4 according to the discrimination result. Optimal control of settings. If none of the above-described determination conditions is satisfied, the system control unit 5 displays the “AUTO” icon image of FIG. 2 on the live screen and does not perform any special control.

  Next, image quality adjustment processing such as exposure correction, saturation adjustment, contrast correction, and white balance adjustment based on a user operation on the operation member 12 will be described with reference to FIGS. 5 and 6.

  FIG. 5 is a diagram illustrating an example of an image quality adjustment screen displayed on the display unit 11. In the present embodiment, a system capable of changing aperture / exposure correction / saturation, hue, and contrast will be considered.

  In FIG. 5, a scene icon 106 is an icon indicating the scene discrimination result shown in FIG. The button icon 100 is a button for closing the image quality adjustment screen, and is a button for ending image editing by a user operation and returning to a normal live display screen. Button icons 101 to 105 are editing buttons for various image quality parameters. When any one of the button icons is touched or selected by a key operation, the screen changes to an individual change screen for various parameters. Examples of some editing operations will be described below.

  FIG. 6A shows an example of the aperture value change screen when the button icon 101 in FIG. 5 is selected. In FIG. 6A, a slider position corresponding to the current aperture value is set as an initial value, and the user can change the aperture value to an arbitrary value by changing the slide position of the slider 200. . When the user's aperture value designation input is received, the system control unit 5 changes the aperture mechanism 1c of the photographing optical system 1 to the aperture value set by the user in real time via the exposure amount control unit 6. As a result, the user can check the image quality at an arbitrary aperture value during shooting standby.

  FIG. 6B is a diagram illustrating an example of a saturation change screen when the button icon 103 in FIG. 5 is selected. In FIG. 6B, the vividness of the image can be controlled by the same operation as the aperture value described in FIG. 6A, and the saturation can be increased by moving the slider 200 in the + direction. It is also possible to lower the saturation by moving 200 in the-direction. As shown in FIG. 6B, it is also possible to move the slider 200 toward the end in the − (minus) direction to finally form an achromatic (monochrome) image. Upon receiving the user's saturation setting input, the system control unit 5 changes image processing parameters in the image processing circuit 4.

  Although details are omitted, the user can adjust the image quality with the same screen configuration for the brightness, hue, and contrast in FIG. Thereby, the user can perform a simulation of image quality after shooting on the live screen.

  Next, the compatibility between the scene determination process and the image quality adjustment process based on the user operation on the operation member 12 will be described with reference to FIGS. As described above, in the scene determination process, the shooting scene is sequentially analyzed during shooting standby, and the optimum image processing effect and shooting setting are selected. In addition, the user can make a desired image quality adjustment by an image quality adjustment process based on a user operation on the operation member 12 with respect to the image quality to which the effect of the scene determination process is added.

  However, for example, as in the “macro” scene of FIG. 2, there is a concern that the effect of “opening the aperture” by the scene determination process and the aperture value set based on the user operation on the operation member 12 may conflict. Therefore, in the present embodiment, the scene discrimination process and the image adjustment process based on the user setting are made compatible with each other as follows.

  FIG. 7 is a flowchart illustrating a process for making the scene determination process compatible with the image adjustment process based on the user operation. Each process in FIG. 7 is executed by the CPU or the like by developing a program stored in the ROM or the like of the system control unit 5 in the RAM.

  In FIG. 7, in step S700, the system control unit 5 starts the scene determination process described in FIG. 3, and proceeds to step S701. In step S701, the system control unit 5 determines whether or not an image quality adjustment process based on a user operation has been instructed. If instructed, the process proceeds to step S702. If not instructed, the system control unit 5 returns to step S700 to determine the scene determination. Continue processing.

  In step S702, the system control unit 5 executes an effect conflict determination process based on the determination result of the current scene determination process and the image quality adjustment parameter designated by the user operation. Then, the system control unit 5 proceeds to one of step S703, step S704, and step S705 in accordance with the effect competition determination result.

  Here, a specific example of the effect conflict determination process in step S702 will be described with reference to FIGS.

  First, as shown in FIG. 8A, a case where the aperture value is changed by a user operation in a state where it is determined as a “macro” scene will be considered. In accordance with the effect of the “macro” scene in FIG. 2, shooting is performed with the aperture value (F value) set as open as possible. However, when the user changes the aperture value to the “throttle” side, priority is given to the adjustment contents by the user operation over the effect of the scene discrimination process, and the aperture is set to the aperture value specified by the user, but is currently displayed. The “macro” icon image is not consistent with the intended effect.

  For this reason, the system control unit 5 updates the “macro” icon image to the “AUTO” icon image. As described above, the effect of the current scene determination process is canceled by an input by a user operation, and the process of updating the scene determination process and the display of the icon image is referred to as “scene icon change” in step S703.

  As another processing method of “scene icon change”, for example, as shown in FIG. 9, the image processing effect by the scene discrimination processing is changed by the setting by the user operation by changing the expression method of the scene icon image. There is also a way to tell the user. In this case, the display of the icon image during effect change shown in FIG. 9 is fixed until the setting of the image quality parameter by the user operation is canceled or the scene is changed to a scene different from the “macro” scene by the scene determination process.

  On the other hand, as shown in FIG. 8B, when the aperture value designated by the user operation is set to the “open” side with respect to the predetermined aperture value, the system control unit 5 displays “ It is determined that the effect of the “macro” scene matches the aperture value specified by the user. Then, the system control unit 5 continuously displays the “macro” icon image, and sets this as “no change” in step S704.

  Next, as illustrated in FIG. 8C, when the user sets the aperture value adjustment amount to a “squeeze” side by a predetermined value or more while shooting a subject that does not correspond to the “macro” scene. explain. In this case, the scene determination result and the aperture value setting by the user operation match when the aperture value is set to the “throttle” side by the user. However, the system control unit 5 places a restriction on the determination algorithm of the scene determination process so that it is not determined as a “macro” scene.

  As a result, as shown in FIG. 8C, even if a subject to be determined as a “macro” scene is photographed thereafter, it is not determined as a “macro” scene. In this way, the process for restricting at least a part of the scene discrimination process in accordance with the set value designated by the user operation is referred to as “scene discrimination restriction” in step S705.

  Next, another specific example of the effect competition determination process in step S702 will be described with reference to FIGS.

  FIG. 10 illustrates a case where the “brightness” parameter is changed by a user operation in a state where the scene is determined as a “night scene” by the scene determination process. According to FIG. 2, the effect of the “night scene” scene is to “optimize the exposure to the night scene”, but depending on the adjustment amount of the brightness change by the user operation, the scene discrimination processing may not achieve the intended brightness. There is sex.

  Therefore, when the adjustment amount of the brightness setting by the user operation is a predetermined amount or more in the + direction, the system control unit 5 converts the scene determination result currently determined as “night view” in step S703 into the “AUTO” icon image. change. Alternatively, the system control unit 5 restricts a part of the scene determination process in step S705 so that it is not determined to be a “night view” scene.

  FIG. 11 illustrates a case where the “saturation” parameter is changed by a user operation in a state where the scene is determined to be a “blue sky” scene by the scene determination process. According to FIG. 2, the effect of the “blue sky” scene is “to make the blue sky vivid”. For example, the saturation is set in the − (minus) direction by the saturation change by the user operation, and FIG. ) May be set to an achromatic color (monochrome) as shown in FIG. In this case, there is a possibility that the displayed image is monochrome even though the scene determination result is “blue sky”.

  Therefore, the system control unit 5 changes the scene determination result or restricts a part of the scene determination process according to the saturation set by the user operation. For example, when the amount of change in the saturation parameter set by the user operation is greater than or equal to a predetermined amount in the − (minus) direction, the system control unit 5 determines the scene determination result currently determined as “blue sky” in step S703. Is changed to an “AUTO” icon image. Alternatively, the system control unit 5 restricts a part of the scene determination processing in step S705 so that it is not determined to be a “blue sky” scene thereafter. Although the same problem may occur in the “evening scene” scene of FIG. 2, the description can be omitted because it can be solved by the same coping method.

  As described above, in the present embodiment, the scene determination process and the image quality adjustment process based on the user operation can be made compatible without any sense of incongruity. Accordingly, the user can give a high-quality image according to the determination result of the scene determination process, and can reflect his / her favorite image quality adjustment on the captured image.

(Second Embodiment)
Next, a digital camera which is a second embodiment of the imaging apparatus of the present invention will be described with reference to FIG. In the present embodiment, the same parts as those in the first embodiment will be described with reference to the drawings and symbols.

  FIG. 12 is a flowchart illustrating a process for making the scene determination process compatible with the image adjustment process based on the user operation. The processes in steps S1200 to S1202, S1204, and S1205 in FIG. 12 are the same as the processes in steps S700 to S702, S704, and S705 in the first embodiment (FIG. 7), and therefore only step S1203 will be described.

  A case will be described as an example where the aperture value is changed by a user operation in a state where the scene is determined to be a “macro” scene as shown in FIG. 8A or 8B. In this case, as described above, the effect of the “macro” scene in FIG. 2 does not match the aperture value set by the user operation. Therefore, similarly to the description of step S703 in FIG. 7, the setting by the user operation is prioritized over the effect of the scene determination process, and the aperture is set to the aperture value specified by the user operation.

  Here, in step S1203 of FIG. 12, the system control unit 5 does not change the scene icon image, changes only the effect (aperture value) internally, and the scene icon image displays a “macro” icon. to continue.

  This is effective when there is a concern about flickering of the screen transition when the scene icon image is appropriately changed according to the setting by the user operation (change of the aperture value) as in step S703 in FIG. Whether to select step S703 in FIG. 7 or step S1203 in FIG. 12 is determined according to the design policy of the camera. Other configurations and operational effects are the same as those of the first embodiment.

  In addition, this invention is not limited to what was illustrated by said each embodiment, In the range which does not deviate from the summary of this invention, it can change suitably.

  The present invention can also be realized by executing the following processing. That is, the present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in the computer of the system or apparatus read the program. It can also be realized by processing to be executed. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

DESCRIPTION OF SYMBOLS 1 Image pick-up optical system 2 Image sensor 3 Memory 4 Image processing circuit 5 System control part 6 Exposure amount control part 11 Display part 12 Operation member

Claims (9)

An imaging apparatus that automatically determines a shooting scene, controls the imaging apparatus so that an effect according to the determination result is added to the captured image, and includes a control unit that displays the captured image with the effect added live. There,
Adjustment means for receiving a user operation for adjusting the image quality of the displayed captured image;
The image pickup apparatus according to claim 1, wherein, when the determination of the shooting scene is updated, the control unit controls the shooting scene determination process in accordance with the adjustment content of the adjustment unit.   The imaging apparatus according to claim 1, wherein the adjustment unit adjusts at least one of parameters used for exposure correction, saturation adjustment, contrast correction, and white balance adjustment.   The imaging apparatus according to claim 1, wherein the control unit limits a shooting scene determination process when a shooting scene determination result matches an effect of image quality adjustment by the user operation.   The imaging apparatus according to any one of claims 1 to 3, wherein the control unit limits a photographing scene determination process when an adjustment amount of image quality adjustment by the user operation is equal to or greater than a predetermined value.   The imaging apparatus according to claim 1, wherein the control unit notifies the user of the determination result.   The imaging apparatus according to claim 5, wherein the control unit displays an icon image predetermined according to the determination result together with the captured image and notifies the user.   When the image quality adjustment is performed by the user operation before notifying the user of the determination result of the shooting scene, the control means limits the shooting scene determination processing according to the adjusted image quality. The imaging apparatus according to claim 1. A control step of automatically determining a shooting scene, controlling the imaging device so that an effect according to the determination result is given to the shot image, and displaying the shot image to which the effect is given live;
An adjustment step for accepting a user operation for adjusting the image quality of the displayed captured image,
The method of controlling an imaging apparatus according to claim 1, wherein when the determination of the shooting scene is updated, the determination process of the shooting scene is limited according to the adjustment contents in the adjustment step.   A program for causing a computer to execute each step of the method for controlling an imaging apparatus according to claim 8.