Image control device, imaging device, and image control method

Abstract

A good light reduction effect is obtained during imaging. [Solution] The imaging control device 200 includes an acquisition means 201 that acquires information about a subject contained in an image generated by imaging through an optical system, and a selection means 202 that selects at least one of the following based on the information about the subject: inserting an ND filter into the optical system or a synthesis process that synthesizes multiple images generated by imaging to obtain a light-reducing effect.

Description

Technical Field

[0001] The present invention relates to an imaging device having a function capable of obtaining a dimming effect.

Background Art

[0002] At the time of imaging, an appropriate exposure amount can be obtained by inserting and removing an ND (Neutral Density) filter with respect to an optical system according to the brightness of a subject. Patent Document 1 discloses an imaging device that controls exposure by inserting and removing an ND filter or changing an exposure time, an aperture value, an ISO sensitivity, etc. based on information such as panning and exposure time when reducing the amount of light taken in by an image sensor. Patent Document 2 discloses an imaging device that obtains an image with appropriate exposure by synthesizing a plurality of images obtained by imaging a plurality of times without using an ND filter.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] A function capable of obtaining a better dimming effect than conventional imaging devices is required.

Means for Solving the Problems

[0005] An imaging control device, as one aspect of the present invention, is characterized by having an acquisition means for acquiring information about a subject contained in an image generated by imaging through an optical system, and a selection means for selecting at least one of the following based on the information about the subject: inserting an ND filter into the optical system or a synthesis process that synthesizes multiple images generated by imaging to obtain a light-reducing effect. An imaging device including the above imaging control device also constitutes another aspect of the present invention.

[0006] Another aspect of the present invention is an imaging control method, characterized by comprising the steps of: acquiring information about a subject contained in an image generated by imaging through an optical system; and selecting at least one of the following based on the information about the subject: inserting an ND filter into the optical system or a synthesis process that synthesizes multiple images generated by imaging to obtain a light-reducing effect. A program that causes a computer to execute a process according to the above imaging control method also constitutes another aspect of the present invention. [Effects of the Invention]

[0007] According to the present invention, a good light reduction effect can be obtained in imaging. [Brief explanation of the drawing]

[0008] [Figure 1] A block diagram showing the configuration of the imaging device in the embodiment. [Figure 2] A diagram showing the configuration of the attenuation information generation unit in the imaging device of the embodiment. [Figure 3] A diagram showing the light reduction process in the imaging device of the embodiment. [Figure 4] A diagram showing the configuration of the light reduction method determination unit in the imaging device of the embodiment. [Figure 5] A flowchart showing the processes performed by the dimming method determination unit in the embodiment. [Figure 6] A diagram showing a turret-type ND filter in an embodiment. [Figure 7] A diagram showing an ND filter formed by stacking polarizing filters in an example. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. [Examples]

[0010] Figure 1 shows the configuration of the imaging device 100 in the embodiment. Each block in the figure can be realized by a combination of an integrated circuit (IC) such as an ASIC or FPGA, a discrete circuit, or a memory and a processor that executes the program stored therein. Furthermore, one block may be realized by multiple integrated circuit packages, or multiple blocks may be realized by one integrated circuit package. Also, the same block may be realized in different configurations depending on the operating environment and required capabilities. In the following description, the case in which the imaging device 100 is a digital camera will be described, but the imaging device may also be a camera provided in a mobile terminal such as a tablet computer or smartphone.

[0011] The imaging device 100 includes a control unit 101, a ROM 102, a RAM 103, an optical system 104, an imaging unit 105, an A / D conversion unit 106, a UI unit 107, an image processing unit 108, a display unit 109, and a light reduction processing unit 110, which are interconnected by a bus 111.

[0012] The control unit 101 is a computer composed of a CPU and the like, and controls the operation of each block in the imaging device 100 by reading the program for each block from the ROM 102, loading it into the RAM 103, and executing it.

[0013] ROM 102 is an electrically erasable and recordable non-volatile memory that stores the operation programs of each block in the imaging device 100 and the parameters necessary for the operation of each block. RAM 103 is a rewritable volatile memory that is used for deploying programs executed by the control unit 101, etc., and for temporary storage of data generated by the operation of each block in the imaging device 100.

[0014] The optical system 104 is composed of a plurality of lenses including a zoom lens and a focus lens and an aperture, and forms an image of light from a subject on the imaging surface of the imaging unit 105. The optical system 104 also includes an ND filter that can be inserted and removed in the optical path for exposure adjustment.

[0015] The imaging unit 105 is composed of an imaging element such as a CCD sensor or a CMOS sensor, photoelectrically converts the optical image (subject image) formed on the imaging surface by the optical system 104, and outputs an analog imaging signal to the A / D conversion unit 106. The A / D conversion unit 106 converts the input analog imaging signal into a digital imaging signal and outputs it. The digital imaging signal output from the A / D conversion unit 106 is temporarily stored in the RAM 103. The A / D conversion unit 106 may be built into the imaging unit 105.

[0016] The UI unit 107 accepts a user's operation on the imaging device 100 and is composed of a pointing device, a keyboard, etc. The pointing device is a touch panel, a mouse, etc.

[0017] The image processing unit 108 performs various image processes such as white balance adjustment, color interpolation, and gamma processing on the digital imaging signal stored in the RAM 103 to generate image data, and temporarily stores the image data in the RAM 103.

[0018] The display unit 109 is composed of a display device such as an LCD that displays an image corresponding to the image data stored in the RAM 103. The display unit 109 also performs UI display for receiving an instruction from the user.

[0019] The dimming processing unit 110 is a computer composed of an MPU or the like, and performs an image synthesis process for adjusting the exposure (obtaining a dimming effect) on the image data stored in the RAM 103. The dimming processing unit 110 also includes a dimming information generation unit 200 shown in FIG. 2.

[0020] The light reduction information generation unit 200 includes a subject information acquisition unit 201, a light reduction method determination unit 202, an ND filter control unit 203, and an image synthesis unit 204. The light reduction information generation unit 200 corresponds to an imaging control device and an image processing device, and may be provided as a personal computer outside the imaging device 100.

[0021] The captured image shown in Figure 2 as the input image corresponds to the image data generated by the image processing unit 108. An example of the format of the captured image processed by the light reduction information generation unit 200 is RGB (BAYER-RAW) in a Bayer array. In this case, the image data consists of R pixels, G pixels, and B pixels with linear signal characteristics.

[0022] The subject information acquisition unit 201, as an acquisition means, acquires information about the subject (hereinafter referred to as subject information) from the captured image. The subject information includes information about the region containing the subject as the object focused by the optical system 104 (hereinafter referred to as the subject region), and information about the saturation pixel count, saturation, degree of gradation, and brightness change amount in the subject region, which will be described later. In this embodiment, information about A includes not only information that represents A itself, but also information that can be converted to A.

[0023] The light reduction method determination unit 202, acting as a selection means, determines (selects) a light reduction method based on the captured image and subject information acquired by the subject information acquisition unit 201. Details of the light reduction method determination unit 202 will be described later.

[0024] The ND filter control unit 203 determines the control (adjustment) of the ND filter based on the light reduction method determined by the light reduction method determination unit 202, and generates ND filter information indicating the content of the determination. Specifically, if it is determined that a light reduction effect of 3 stops should be obtained by the ND filter, the unit generates ND filter information indicating the insertion of the ND filter so that a light reduction effect of 3 stops (ND8) is obtained.

[0025] The ND filter configuration may involve moving a plate that holds one type of ND filter to insert and remove the ND filter, or it may use a turret-type ND filter as shown in Figure 6 or a polarizing filter type ND filter as shown in Figure 7. The turret-type ND filter has a configuration in which a specific ND filter is placed in the optical path by rotating a plate P on which multiple types of ND filters ND1 to ND4, each having different light transmittances, are arranged in the circumferential direction. The polarizing filter type ND filter allows the amount of light reduction to be adjusted by rotating an ND filter ND5, which is made up of multiple polarizing filters stacked on top of each other. The control unit 101 controls the insertion, removal, and rotation of the ND filter (hereinafter referred to as ND filter control) based on the ND filter information. By performing such ND filter control, it is possible to generate an image as an output image with the correct exposure state.

[0026] The image synthesis unit 204, as a processing means, performs image synthesis processing based on the captured image and the light reduction method determined by the light reduction method determination unit 202 to generate a composite image. Specifically, when the light reduction method determination unit 202 decides to obtain a light reduction effect of 3 stops (ND8) through image synthesis processing, it generates image synthesis information indicating the content of the decision. Based on the image synthesis information, the image synthesis unit 204 performs image synthesis processing to generate a composite image with a light reduction effect of 3 stops. In this case, the image synthesis unit 204 performs image synthesis processing to synthesize multiple segmented exposure images obtained by multiple segmented imaging performed by dividing a predetermined exposure time into multiple segments. By minimizing the time when no exposure is performed, i.e., the non-exposure time, from the end of exposure of the imaging unit 105 for generating one segmented exposure image to the start of exposure of the imaging unit 105 for generating the next segmented exposure image, it is possible to generate a composite image as an output image with suppressed blurring of the subject image. As a light reduction method by image synthesis processing, for example, the method disclosed in Patent Document 2 may be used, or other methods may be used.

[0027] The degree of light reduction effect (number of steps) in the image synthesis process may be changed for each region within the synthesized image. For example, the image synthesis process may be performed so that a 2-step light reduction effect is obtained for regions where the pixel value is above a threshold, and a 1-step light reduction effect is obtained for regions where the pixel value is below the threshold. The image synthesis unit 204 outputs information about the regions where the light reduction effect was obtained in the image synthesis process as image synthesis information.

[0028] Information regarding the light-reducing effect of inserting an ND filter or image synthesis (such as the number of light-reducing steps and the region where the light-reducing effect was obtained) is recorded as metadata in the captured image generated by imaging with an ND filter inserted, or in the composite image generated by image synthesis, i.e., the output image. Furthermore, ND filter control and image synthesis may be performed based on newly acquired images, previously recorded images, and metadata of previously recorded images.

[0029] As described above, in this embodiment, by selecting and performing ND filter control or image synthesis processing based on subject information, an output image (captured image or composite image) with appropriate exposure can be obtained.

[0030] Figure 4 shows the configuration of the dimming method determination unit 202. The dimming method determination unit 202 includes a dimming determination unit 401, a saturated pixel count calculation unit 402, a subject saturation calculation unit 403, a subject gradation calculation unit 404, a brightness change amount calculation unit 405, and a dimming method information generation unit 406.

[0031] The light reduction determination unit 401 determines whether the exposure of the subject area in the captured image is overexposed or not, and outputs an exposure determination flag indicating the result of the determination. The saturation pixel count calculation unit 402 calculates the saturation pixel count, which is the number of pixels in the subject (i.e., the subject area as an image area) that are saturated in brightness.

[0032] The subject saturation calculation unit 403 calculates the saturation of the subject in the subject area. Specifically, the subject saturation calculation unit 403 performs interpolation processing by smoothing filter processing on the BAYER-RAW format image to generate an average interpolated image in RGB444 format and calculates the saturation of the subject from the average interpolated image.

[0033] An example of how to generate an average interpolated image is shown below. Figures 3(a) to 3(d) show an example of interpolation processing using a 3x3 smoothing filter on an image captured in BAYER-RAW format. Figure 3(a) shows an image captured in BAYER-RAW format (simply referred to as BAYER array in the figure). Figure 3(b) shows an R-interpolated image obtained by applying a smoothing filter to the R pixels of the BAYER array image. Figure 3(c) shows a G-interpolated image obtained by applying a smoothing filter to the G pixels of the BAYER array image. Furthermore, Figure 3(d) shows a B-interpolated image obtained by applying a smoothing filter to the B pixels of the BAYER array image. The 3-4 digit number written below each pixel indicates the pixel value of that pixel.

[0034] The pixel values ​​of the R-interpolated image shown in Figure 3(b) are determined by applying a 3x3 smoothing filter to the captured image in Figure 3(a). This process leaves the pixel value of the reference R pixel corresponding to the R pixel in the captured image unchanged, while the pixel values ​​of the other R pixels are calculated by interpolation using the pixel value of the reference R pixel. In this way, the pixel values ​​(R values) of all R pixels in the R-interpolated image are determined. Similarly, the pixel values ​​(G values) of all G pixels in the G-interpolated image and the pixel values ​​(B values) of all B pixels in the B-interpolated image shown in Figures 3(c) and (d) are determined in the same manner.

[0035] The subject saturation is calculated using the following formula (1).

[0036]

number

[0037] In equation (1), Chro represents the subject saturation calculated from the average interpolated image in RGB444 format. MAX_ RGB This indicates the maximum value among the R, G, and B values ​​in the subject area of ​​the average interpolated image in RGB444 format. Also, MIN_ RGB This indicates the minimum R, G, and B values ​​in the subject area of ​​the average interpolated image.

[0038] The subject gradation calculation unit 404 calculates a gradation degree that indicates the degree of smoothness of the gradation of the subject in the subject area. Specifically, the subject gradation calculation unit 404 performs interpolation processing by smoothing filter processing on the captured image in BAYER-RAW format, outputs an average interpolated image in RGB444 format, and calculates the gradation degree from the average interpolated image. The method for generating the average interpolated image is the same as that of the subject saturation calculation unit 403.

[0039] The degree of gradation is calculated using the following formula (2).

[0040]

number

[0041] In equation (2), Grad represents the degree of gradation. N represents the number of pixels in the subject area in the average interpolated image in RGB444 format. i represents the position of each pixel. R, G, and B represent the R, G, and B values ​​in the subject area in the average interpolated image, respectively. The smoothness of the gradation can be evaluated by calculating the average from the difference in pixel values ​​of adjacent pixels using equation (2).

[0042] The brightness change calculation unit 405 calculates the change in brightness of the subject in the subject area. The change in brightness is calculated using the following equation (3).

[0043]

number

[0044] Val represents the change in brightness, and t represents time. R, G, and B represent the R, G, and B values ​​in the subject area of ​​the average interpolated image in RGB444 format, respectively. By using equation (3), the change in brightness can be evaluated by calculating the change in pixel value over time at the same pixel position.

[0045] The light reduction method information generation unit 406 generates the aforementioned ND filter information and image synthesis information from the exposure determination flag, saturation pixel count, subject saturation, subject gradation degree, and subject brightness change amount, respectively.

[0046] The flowchart in Figure 5 shows the process that the dimming method determination unit 202 executes according to the program.

[0047] In step S501, the light reduction method determination unit 202 determines whether the exposure determination flag indicates an overexposure state, that is, whether it is necessary to obtain a light reduction effect by ND filter control or image synthesis processing. If it is an overexposure state, it determines that it is necessary to obtain a light reduction effect and performs the process in step S502; if it is not an overexposure state, this process ends.

[0048] In step S502, the light reduction method determination unit 202 determines whether the number of saturated pixels is greater than or equal to a threshold value, that is, whether it is necessary to prioritize the use of an ND filter to obtain a light reduction effect. If the number of saturated pixels is greater than or equal to the threshold value, it determines that the use of an ND filter should be prioritized and performs the process in step S506. If the number of saturated pixels is less than the threshold value, it performs the process in step S503.

[0049] In step S503, the light reduction method determination unit 202 determines whether the saturation of the subject is equal to or greater than a second predetermined threshold value, that is, whether it is necessary to prioritize the use of image synthesis processing to obtain a light reduction effect. If the saturation is equal to or greater than the threshold value, it determines that the use of image synthesis processing should be prioritized and performs the process in step S509; if the saturation is less than the threshold value, it performs the process in step S504.

[0050] In step S504, the light reduction method determination unit 202 determines whether the degree of gradation of the subject is below a third predetermined threshold, that is, whether it is necessary to prioritize the use of image synthesis processing to obtain a light reduction effect. If the degree of gradation is above the threshold, it determines that the use of image synthesis processing should be prioritized and performs the process in step S509; if the degree of gradation is below the threshold, it performs the process in step S505.

[0051] In step S505, the dimming method determination unit 202 determines whether the amount of change in brightness of the subject is greater than or equal to a threshold value, that is, whether it is necessary to prioritize the use of image synthesis processing to obtain a dimming effect. If the amount of change in brightness is greater than or equal to the threshold value, it determines that the use of image synthesis processing should be prioritized and performs the process in step S509; if the amount of change in brightness is less than the threshold value, it performs the process in step S506.

[0052] In step S506, the light reduction method determination unit 202 generates ND filter information based on the exposure state of the captured image. For example, if the exposure state is 3 stops overexposed, it generates ND filter information to obtain a 3-stop light reduction effect by inserting an ND filter. As a result, the control unit 101 inserts an ND filter into the optical path.

[0053] Next, in step S507, the light reduction method determination unit 202 determines whether the exposure state of the subject area has become appropriate (within a predetermined range) due to the light reduction effect of inserting the ND filter. For example, if the original exposure state in step S506 was 5 stops overexposed, and the insertion of the ND filter only provided a light reduction effect of 3 stops, the unit determines that the exposure state is 2 stops overexposed and therefore inappropriate. If the exposure state is inappropriate, the unit performs the process in step S508. If it is appropriate, the image processing unit 108 generates and outputs an image in which the light reduction effect of the ND filter has been achieved, and terminates this process.

[0054] In step S508, the light reduction method determination unit 202 generates image synthesis information to obtain a light reduction effect through image synthesis processing. For example, if the exposure is two stops overexposed, the unit generates image synthesis information so that a two-stop light reduction effect can be obtained through image synthesis processing. As a result, the light reduction processing unit 110 performs image synthesis processing to generate a composite image with an appropriate exposure state. Then the process ends.

[0055] Meanwhile, in step S509, the light reduction method determination unit 202 generates image synthesis information for performing image synthesis processing based on the exposure state of the captured image. For example, if the exposure state is 3 stops overexposed, it generates image synthesis information to obtain a light reduction effect of 3 stops through image synthesis processing. As a result, the light reduction processing unit 110 performs image synthesis processing to generate a composite image in which the light reduction effect has been obtained.

[0056] Next, in step S510, the light reduction method determination unit 202 determines whether the exposure state of the subject area in the composite image from which the light reduction effect has been obtained is appropriate (within a predetermined range). For example, if the original exposure state in step S509 was 5 stops overexposed, and only a 3-stop light reduction effect was obtained through the image synthesis process, the unit determines that the exposure state is 2 stops overexposed and therefore inappropriate. If the exposure state is inappropriate, the unit performs the processing in step S511; if it is appropriate, it outputs the composite image generated in step S509 and terminates this process.

[0057] In step S511, the light reduction method determination unit 202 generates ND filter information to obtain a light reduction effect by inserting an ND filter. For example, if the exposure is two stops overexposed, the unit generates ND filter information so that a two-stop light reduction effect can be obtained by inserting an ND filter. As a result, the control unit 101 inserts an ND filter into the optical path, and the image processing unit 108 generates and outputs an image in which the light reduction effect of the ND filter has been obtained, thus ending this process.

[0058] In this embodiment, we have described a case where either ND filter insertion or image synthesis processing is selected based on the results of the four judgments in steps S502 to S505. However, it is not necessary to perform all four judgments; at least one judgment is sufficient. For example, in step S502, image synthesis processing may be selected if the number of saturated pixels is less than the threshold, or in step S503, ND filter insertion may be selected if the saturation is less than the threshold. Alternatively, in step S504, ND filter insertion may be selected if the degree of gradation is greater than or equal to the threshold.

[0059] In the imaging device disclosed in Patent Document 1, there are differences in image shake, depth of field, and noise between images captured by adjusting exposure by inserting and removing an ND filter and images captured by adjusting exposure by other methods. Furthermore, the higher the density of the ND filter, the more noticeable the decrease in saturation and density unevenness become. In addition, it is difficult to smoothly change the exposure when switching the density of the ND filter in response to changes in brightness during video capture. Moreover, when obtaining a light reduction effect by image synthesis processing, as in the imaging device disclosed in Patent Document 2, the saturation pixel value may differ from that of an image captured through an ND filter.

[0060] In contrast, this embodiment determines whether to prioritize the ND filter or image synthesis processing to achieve the light-reducing effect based on the saturation pixel count, the saturation of the subject, the degree of gradation, and the amount of brightness change. This makes it possible to suppress the drawbacks that occur when obtaining the light-reducing effect using the ND filter or image synthesis processing described above.

[0061] The above embodiments include the following configuration.

[0062] (Composition 1) An acquisition means for acquiring information about a subject contained in an image generated by imaging through an optical system, An imaging control device characterized by having a selection means that selects at least one of the following based on information about the subject: inserting an ND filter into the optical system and a synthesis process that synthesizes a plurality of images generated by the imaging to obtain a light-reducing effect. (Configuration 2) The imaging control device according to configuration 1, characterized in that the information relating to the subject includes information relating to the saturation pixel count in the subject. (Composition 3) The imaging control device according to configuration 2, characterized in that the selection means selects to insert the ND filter when the saturation pixel count is greater than a first predetermined value. (Composition 4) The imaging control device according to configuration 2 or 3, characterized in that the selection means selects the synthesis process when the number of saturated pixels is smaller than a first predetermined value. (Composition 5) The imaging control device according to any one of configurations 1 to 4, characterized in that the information relating to the subject includes information relating to the saturation of the subject. (Composition 6) The imaging control device according to configuration 5, wherein the selection means selects the synthesis process when the saturation is higher than a second predetermined value. (Composition 7) The imaging control device according to configuration 5 or 6, characterized in that the selection means selects to insert the ND filter when the saturation is lower than a second predetermined value. (Composition 8) The imaging control device according to any one of configurations 1 to 7, characterized in that the information relating to the subject includes information relating to the degree of gradation of the subject. (Composition 9) The imaging control device according to configuration 8, characterized in that the selection means selects the synthesis process when the degree of gradation is lower than a third predetermined value. (Composition 10) The imaging control device according to configuration 8 or 9, characterized in that the selection means selects to insert the ND filter when the degree of gradation is higher than a third predetermined value. (Composition 11) The imaging control device according to any one of configurations 1 to 10, characterized in that the information relating to the subject includes information relating to the amount of change in the brightness of the subject over time. (Composition 12) The imaging control device according to configuration 11, characterized in that the selection means selects the synthesis process when the amount of change in brightness is greater than a fourth predetermined value. (Composition 13) The imaging control device according to configuration 11 or 12, characterized in that the selection means selects to insert the ND filter when the amount of change in brightness is higher than a fourth predetermined value. (Composition 14) The information relating to the subject includes information relating to the saturation pixel count of the subject, information relating to the saturation of the subject, information relating to the degree of gradation of the subject, and information relating to the amount of change in the brightness of the subject over time. The aforementioned selection means is, When the number of saturated pixels is higher than the first predetermined value, and when the number of saturated pixels is lower than the first predetermined value, the saturation is lower than the second predetermined value, the degree of gradation is higher than the third predetermined value, and the amount of change in brightness is smaller than the fourth predetermined value, the insertion of the ND filter is selected, respectively. The imaging control device according to any one of configurations 1 to 13, characterized in that the synthesis process is selected when the saturation is higher than the second predetermined value, when the degree of gradation is lower than the third predetermined value, and when the amount of change in brightness is higher than the fourth predetermined value. (Composition 15) The image capture control device according to any one of configurations 1 to 14, characterized in that the selection means selects the synthesis process when the exposure state of the subject in the image generated by imaging performed with the ND filter inserted is not within a predetermined range. (Composition 16) The imaging control device according to any one of configurations 1 to 15, characterized in that the selection means selects to insert the ND filter when the exposure state of the subject in the image generated by the synthesis process is not within a predetermined range. (Composition 17) The imaging control device according to any one of configurations 1 to 16, characterized in that the synthesis process provides different attenuation effects to each region in the image obtained by synthesizing the plurality of images. (Composition 18) An imaging control device according to any one of configurations 1 to 17, characterized in that it records information regarding the light-reducing effect obtained by inserting the ND filter or by the synthesis process in the output image generated by the imaging or synthesis process performed with the ND filter inserted. (Composition 19) An imaging control device as described in any one of configurations 1 to 18, An imaging device characterized by having an image sensor that performs the aforementioned imaging.

[0063] (Other examples) The present invention can also be realized by supplying a program that implements one or more of the functions of the above-described embodiments to a system or device via a network or storage medium, and by having one or more processors in the computer of that system or device read and execute the program. It can also be realized by a circuit (e.g., an ASIC) that implements one or more functions.

[0064] The embodiments described above are merely representative examples, and various modifications and changes can be made to each embodiment when implementing the present invention. [Explanation of symbols]

[0065] 100 Imaging device 104 Optical system 105 Imaging Unit 200 Light reduction information generation unit 201 Subject information acquisition section 202 Light reduction method determination unit 204 Image Synthesis Unit

Claims

1. An acquisition means for acquiring information about a subject contained in an image generated by imaging through an optical system, An imaging control device characterized by having a selection means that, based on information about the subject, selects at least one of the following: inserting an ND filter into the optical system and a synthesis process that synthesizes a plurality of images generated by the imaging to obtain a light-reducing effect.

2. The imaging control device according to claim 1, characterized in that the information relating to the subject includes information relating to the saturation pixel count in the subject.

3. The imaging control device according to claim 2, characterized in that the selection means selects to insert the ND filter when the saturation pixel count is greater than a first predetermined value.

4. The imaging control device according to claim 2, characterized in that the selection means selects the synthesis process when the number of saturated pixels is smaller than a first predetermined value.

5. The imaging control device according to claim 1, characterized in that the information relating to the subject includes information relating to the saturation of the subject.

6. The imaging control device according to claim 5, characterized in that the selection means selects the synthesis process when the saturation is higher than a second predetermined value.

7. The imaging control device according to claim 5, characterized in that the selection means selects to insert the ND filter when the saturation is lower than a second predetermined value.

8. The imaging control device according to claim 1, characterized in that the information relating to the subject includes information relating to the degree of gradation of the subject.

9. The imaging control device according to claim 8, characterized in that the selection means selects the synthesis process when the degree of gradation is lower than a third predetermined value.

10. The imaging control device according to claim 8, characterized in that the selection means selects to insert the ND filter when the degree of gradation is higher than a third predetermined value.

11. The imaging control device according to claim 1, characterized in that the information relating to the subject includes information relating to the amount of change in the brightness of the subject over time.

12. The imaging control device according to claim 11, characterized in that the selection means selects the synthesis process when the amount of change in brightness is greater than a fourth predetermined value.

13. The imaging control device according to claim 11, characterized in that the selection means selects to insert the ND filter when the amount of change in brightness is higher than a fourth predetermined value.

14. The information relating to the subject includes information relating to the saturation pixel count of the subject, information relating to the saturation of the subject, information relating to the degree of gradation of the subject, and information relating to the amount of change in the brightness of the subject over time. When the number of saturated pixels is higher than a first predetermined value, and when the number of saturated pixels is lower than a first predetermined value, the saturation is lower than a second predetermined value, the degree of gradation is higher than a third predetermined value, and the amount of change in brightness is smaller than a fourth predetermined value, the insertion of the ND filter is selected, respectively. The imaging control device according to claim 1, characterized in that the synthesis process is selected when the saturation is higher than the second predetermined value, when the degree of gradation is lower than the third predetermined value, and when the amount of change in brightness is higher than the fourth predetermined value, respectively.

15. The imaging control device according to claim 1, characterized in that the selection means selects the synthesis process when the exposure state of the subject in the image generated by imaging performed with the ND filter inserted is not within a predetermined range.

16. The imaging control device according to claim 1, characterized in that the selection means selects to insert the ND filter when the exposure state of the subject in the image generated by the synthesis process is not within a predetermined range.

17. The imaging control device according to claim 1, characterized in that the synthesis process provides different attenuation effects to each region in the image obtained by synthesizing the plurality of images.

18. The imaging control device according to claim 1, characterized in that it records information regarding the light-reducing effect obtained by inserting the ND filter or by the synthesis process in the output image generated by the imaging or synthesis process performed with the ND filter inserted.

19. An imaging control device according to any one of claims 1 to 18, An imaging device characterized by having an image sensor that performs the aforementioned imaging.

20. The steps include: obtaining information about the subject contained in the image generated by imaging through an optical system, An imaging control method characterized by having the step of selecting at least one of the following based on information about the subject: inserting an ND filter into the optical system and a synthesis process that synthesizes a plurality of images generated by the imaging to obtain a light-reducing effect.

21. A program characterized by causing a computer to execute processing according to the imaging control method described in claim 20.

Images