JP2007019643A - Imaging apparatus and imaging method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform underwater photography under proper exposure conditions. <P>SOLUTION: The imaging apparatus has a photographic environment selecting means of making the selection of whether an imaging element mounted with a plurality of color filters photographs in air or underwater, an exposure evaluated value calculating means of calculating an exposure evaluated value for evaluating the exposure state of a video signal outputted from the imaging element corresponding to the plurality of color filters, and a photographing means of photographing under exposure conditions determined based upon the exposure evaluated value calculated by the exposure evaluated value calculating means. The exposure evaluated value calculating means has a weighting means of multiplying the output of the imaging element mounted with the plurality of color filters by weight coefficients by colors, and the weight coefficients by the colors are changed according to environments of photography selected by the photographic environment selecting means to obtain exposure evaluated values suitable for underwater photography and in-air photography. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an image pickup apparatus, an image pickup method, a computer program, and a recording medium, and more particularly to a technique suitable for use in an image pickup apparatus that takes images in the air or in the water.

  Conventionally, the method for generating an exposure evaluation value in exposure control in underwater shooting using the image sensor and in air (land) shooting is the same, and an image sensor having a plurality of color filters (for example, primary colors R, G, B) In the system using, an exposure evaluation value is generated by applying a weighting factor to each color output signal according to each color, and the exposure conditions (aperture, shutter speed, sensitivity) for shooting are determined based on the exposure evaluation value. In this system, there is no difference in the weighting coefficient according to the color between the water and the air (see, for example, Patent Document 1). Generally, the weighting coefficient is (R: G: B) = (0.299: 0.587: 0.114) Or, a value approximate to the numerical value is used.

JP 2004-282460 A

  However, in water, the transmittance on the long wavelength side of light is greatly attenuated compared to air. For this reason, in water, the red output signal from the image sensor is small, and the blue output signal is relatively large.

  However, since the weight for blue when generating the exposure evaluation value is small as described above, there is a problem that an appropriate exposure condition cannot be obtained in water with only a few red components and a large amount of blue components as a light source. In particular, the image sensor has a narrow dynamic range compared to silver salt film, so if you shoot with exposure conditions determined using the exposure evaluation value generated with the same weighting coefficient as in air, the image looks like a saturated blue level of high brightness. There was an easy problem.

  In view of the above-described problems, an object of the present invention is to provide a camera capable of photographing under appropriate exposure conditions similar to those in air even in underwater photographing.

  An image pickup apparatus according to the present invention is an image pickup apparatus having an image pickup element on which a plurality of color filters are mounted, and a shooting environment determination unit that determines whether an environment for shooting with the image pickup element is in air or underwater. An exposure evaluation value calculating means for calculating an exposure evaluation value for evaluating an exposure state of a video signal output from an image sensor corresponding to the plurality of color filters, and an exposure evaluation value calculated by the exposure evaluation value calculating means And an exposure evaluation value calculation unit that includes a weighting unit that applies a weighting factor for each color to the output of the image sensor on which the plurality of color filters are mounted. And the weighting unit changes the weighting coefficient for each color according to the shooting environment determined by the shooting environment determination unit.

  The imaging method of the present invention is an imaging method having an imaging device equipped with a plurality of color filters, and an imaging environment determination step of determining whether an environment for imaging with the imaging device is in air or in water An exposure evaluation value calculating step for calculating an exposure evaluation value for evaluating an exposure state of a video signal output from an image sensor corresponding to the plurality of color filters, and an exposure evaluation value calculated by the exposure evaluation value calculating step The exposure evaluation value calculating step includes a weighting step of applying a weighting factor for each color to the output of the image sensor on which the plurality of color filters are mounted. And, in the weighting step, the weighting coefficient for each color is changed in accordance with the shooting environment determined in the shooting environment determination step.

  The computer program according to the present invention is a computer program for causing a computer to execute an imaging method having an imaging device equipped with a plurality of color filters, and whether the environment for imaging with the imaging device is in air or underwater. An exposure evaluation value calculating step for calculating an exposure evaluation value for evaluating an exposure state of a video signal output from an imaging device corresponding to the plurality of color filters, and the exposure evaluation value calculating step. A photographing step of taking an image by determining an exposure condition based on the exposure evaluation value calculated by the step, wherein the exposure evaluation value calculating step is performed for each color with respect to an output of the image sensor on which the plurality of color filters are mounted. A weighting step of applying a weighting factor, and in the weighting step, according to the shooting environment determined by the shooting environment determination step, Characterized in that to execute the imaging method of changing the weight coefficients of every computer.

  The recording medium of the present invention records the computer program described above.

According to the present invention, since the weighting coefficient for a plurality of colors can be arbitrarily changed when generating the exposure evaluation value, even when underwater shooting is performed, the shooting is performed in the same manner as when shooting in air. It is possible to provide a camera capable of generating an exposure evaluation suitable for the environment and photographing.
In addition, according to another feature of the present invention, the ratio of the blue weighting factor is set higher during underwater shooting than when underwater shooting, so that underwater shooting is performed with an appropriate exposure evaluation value. Can do.

(First embodiment)
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a block diagram illustrating a configuration of an imaging device 50 according to the present embodiment. In FIG. 1, 1 is an optical system such as an imaging lens or a zoom lens that collects light from an object, 2 is a diaphragm device for controlling the amount of light collected by the optical system 1, and 3 is an optical system 1. This is a CCD that converts an optical image collected by the diaphragm device 2 into an electrical signal, and is provided with a plurality of color filters (not shown) in the present embodiment.

  4 has a CDS (correlated double sampling) circuit section for extracting a desired signal component from the electrical signal output from the CCD 3 and an amplification circuit for amplifying the signal, and A / A for converting the amplification circuit output signal into a digital signal. A CDS / A / D circuit 5 having a D circuit portion is a TG circuit for generating a drive pulse for driving the CCD 3.

  6 is a data bus, 7 is a storage device (memory) for storing various data, 8 is a video signal output from the CDS / A / D circuit 4, or after the video signal is temporarily stored in the memory 7. An integration circuit that divides the video signal into predetermined blocks from the video signal read from the memory 7 at a predetermined timing, integrates the signal for each divided block and for each type of color filter of the CCD 3, and 9 is an integration circuit. 8 is a photometric evaluation circuit that generates an evaluation value for photometry from the integrated values of a plurality of colors integrated for each block by 8.

  Reference numeral 10 denotes a video signal output from the CDS / A / D circuit 4 or a video signal read out from the memory 7 at a desired timing after the video signal is temporarily stored in the memory 7 to perform a desired process. A signal processing circuit having a signal form of 11, a compression circuit for compressing the video signal processed by the signal processing circuit 10 into a desired compression form, 12 a recording medium for recording the signal compressed by the compression circuit 11, and 13 Strobe device.

  Reference numeral 14 denotes a CPU functioning as a control means for controlling the entire system of the present embodiment, and 15 denotes an operation unit for operating the system of the present embodiment, which has a photometric method selection button and a release button, It is assumed that a button for selecting shooting and shooting in the air is provided.

FIG. 2 is a block diagram showing the configuration of the photometric evaluation circuit 9 in detail.
In FIG. 2, reference numeral 21 denotes a weighting circuit, which weights the integration values of a plurality of colors integrated for each block by the integration circuit 8 according to each block. In the present embodiment, the CPU 14 generates a coefficient for each block in accordance with the photometry method selected by the operation unit 15 (for example, evaluation photometry method, spot metering, etc.), and the coefficient is integrated with each color of each block. Multiply by value.

An exposure evaluation value generation circuit 22 weights the output of the weighting circuit 21 for each color, and generates an exposure evaluation value as a photometric result. The signal flow will be described in detail. For example, the CCD 3 has primary color (red, green, blue) = (R, G, B) filters, and the integration circuit 8 displays an image (vertical a block, horizontal b block). , The output of the integrating circuit 8 is
_{(SR 11, sG 11, sB} 11), (sR 12, sG 12, sB 12), (sR 13, sG 13, sB 13), ···· (sR 1b, sG 1b, sB 1b)
_{(SR 21, sG 21, sB} 21), (sR 22, sG 22, sB 22), (sR 23, sG 23, sB 23), ···· (sR 2b, sG 2b, sB 2b)
...
(SR _a1 , sG _a1 , sB _a1 ), (sR _a2 , sG _a2 , sB _a2 ), (sR _a3 , sG _a3 , sB _a3 ), ... (sR _ab , sG _ab , sB _ab )
It becomes.

If the weights given to each block from the CPU 14 are as follows:
W ₁₁ , W ₁₂ , W ₁₃ , ... W _1b
W ₂₁ , W ₂₂ , W ₂₃ , ... W _2b
...
W _a1 , W _a2 , W _a3 , ... W _ab
It becomes.

The output of the weighting circuit 21 is as follows.
W ₁₁ * (sR ₁₁ , sG ₁₁ , sB ₁₁ ), W ₁₂ * (sR ₁₂ , sG ₁₂ , sB ₁₂ ), W ₁₃ * (sR ₁₃ , sG ₁₃ , sB ₁₃ ), ... W _1b * ( sR _1b , sG _1b , sB _1b )
W ₂₁ * (sR ₂₁ , sG ₂₁ , sB ₂₁ ), W ₂₂ * (sR ₂₂ , sG ₂₂ , sB ₂₂ ), W ₂₃ * (sR ₂₃ , sG ₂₃ , sB ₂₃ ), ... W _2b * ( sR _2b , sG _2b , sB _2b )
...
W _a1 * (sR _a1 , sG _a1 , sB _a1 ), W _a2 * (sR _a2 , sG _a2 , sB _a2 ), W _a3 * (sR _a3 , sG _a3 , sB _a3 ), ... W _ab * ( sR _ab , sG _ab , sB _ab )

The exposure evaluation value generation circuit 22 receives the output of the weighting circuit 21, adds the weighted integral value of each block for each color, and then adds the weighted value according to each color, thereby adding the exposure evaluation value Yexp. Is generated as follows. Note that k _r1, k _g1, k _b1 are weighting coefficients for the respective colors (R, G, B).
Yexp = k _r1 * ΣsR + k _g1 * ΣsG + k _b1 * ΣsB
ΣsR = W ₁₁ * sR ₁₁ + W ₁₂ * sR ₁₂ + ... + W _1b * sR _1b + W ₂₁ * sR ₂₁ + ... + W _2b * sR _2b + ... + W _ab * sR _ab
ΣsG = W ₁₁ * sG ₁₁ + W ₁₂ * sG ₁₂ + ... + W _1b * sG _1b + W ₂₁ * sG ₂₁ + ... + W _2b * sG _2b + ... + W _ab * sG _ab
ΣsB = W ₁₁ * sB ₁₁ + W ₁₂ * sB ₁₂ + ... + W _1b * sB _1b + W ₂₁ * sB ₂₁ + ... + W _2b * sB _2b + ... + W _ab * sB _ab

FIG. 3 is a flowchart that best represents the characteristics of the imaging apparatus 50 of the present embodiment, and the operation will be described along this flowchart.
As shown in FIG. 3, when the release button is pressed in step S300, the process proceeds to step S301, where the operation status of the operation unit 15 is detected and underwater shooting is selected according to the operation status, or normal rather than underwater. It is determined whether shooting in the air is selected.

As a result of the determination in step S301, if normal shooting in the air is selected, the process proceeds to step S302, and the weight coefficient (the above formula: _kr1, k) of each color in the exposure evaluation value generation circuit 22 in FIG. _{Let g1,} k _b1 ) be the value for shooting in air.

This value is generally set to a value that is the same as or approximate to the ratio of each color component in the following equation for generating a luminance signal from primary color (R, G, B) signals. For example, the luminance signal generation formula is
Y = 0.299 * R + 0.5870 * G + 0.1140 * B
(K _r1, k _g1, k _b1 ) = (0.2990,0.5870,0.1140)
And set.
Or (k _r1, k _g1, k _b1 ) = (0.3,0.6,0.1)
Shall be set.

Therefore, the exposure evaluation value Yexp is
Yexp = k _r1 * ΣsR + k _g1 * ΣsG + k _b1 * ΣsB
It becomes. The weighting coefficient for each color is set in accordance with how the human being perceives the brightness of each color.

On the other hand, if underwater photography has been selected as a result of the determination in step S301, the process proceeds to step S303, in which the weight coefficient of each color in the exposure evaluation value generation circuit 22 in FIG. 2 (the expression: k _r1, k _g1, k _b1 ) is the value for underwater photography. For example, as a coefficient for underwater, the weight coefficient for red is reduced and the weight coefficient for blue is reduced with respect to the coefficient in air, as in ((k _r1, k _g1, k _b1 ) = (0.1,0.5,0.4)). Set a value with an increased coefficient.

  As described above, since long-wavelength light is absorbed by water in water, the red component of the light in water decreases and the ratio of the blue component increases. The coefficient to be generated is set such that the red coefficient is reduced and the blue coefficient is increased with respect to the setting in the air.

  Next, proceeding to step S304, the CPU 14 sets a weighting factor for each block in accordance with the photometry method (for example, evaluation photometry method, spot photometry, etc.) selected by the operation unit 15.

Next, proceeding to step S305, the photometric operation of incident light is performed on the CCD 3 in a state where the coefficients set in steps S302 to S304 are set at desired locations.
Next, the process proceeds to step S306, where exposure conditions (aperture value, shutter speed, sensitivity) for still image shooting are set from the photometric result of step S305.

In step S307, the CCD 3 is exposed under the exposure conditions set in step S306 to capture a still image.
Next, the process proceeds to step S308, and the signal of the CCD 3 exposed in step S307 is read, and the read signal is subjected to CDS (correlated double sampling) for extracting a desired signal component in the CDS / A / D circuit 4 and amplified. Thereafter, A / D conversion is performed. Next, the signal processing circuit 10 performs processing for performing desired processing. Thereafter, in step S309, the data is compressed by the compression circuit 11 and recorded on the recording medium 12.

In the above description, the case where the CCD 3 is a primary color (R, G, B) filter has been described. Next, the CCD 3 is a complementary color (Ye, Cy, G, Mg) filter (= yellow, cyan, green, magenta). A case of consisting of:
When the integration circuit 8 in FIG. 2 divides the image into (vertical a block, horizontal b block), the output of the integration circuit 8 is
(SYe ₁₁ , sCy ₁₁ , sG ₁₁ , sMg ₁₁ ), (sYe ₁₂ , sCy ₁₂ , sG ₁₂ , sMg ₁₂ ), (sYe ₁₃ , sCy ₁₃ , sG ₁₃ , sMg ₁₃ ), ... (sYe _1b , sCy _1b , sG _1b , sMg _1b )
(SYe ₂₁ , sCy ₂₁ , sG ₂₁ , sMg ₂₁ ), (sYe ₂₂ , sCy ₂₂ , sG ₂₂ , sMg ₂₂ ), (sYe ₂₃ , sCy ₂₃ , sG ₂₃ , sMg ₂₃ ), ... (sYe _2b , sCy _2b , sG _2b , sMg _2b )
...
(SYe _a1 , sCy _a1 , sG _a1 , sMg _a1 ), (sYe _a2 , sCy _a2 , sG _a2 , sMg _a2 ), (sYe _a3 , sCy _a3 , sG _a3 , sMg _a3 ), ... (sYe _ab sCy _ab , sG _ab , sMg _ab )
It becomes.

If the weights given to each block from the CPU 14 are as follows:
W ₁₁ , W ₁₂ , W ₁₃ , ... W _1b
W ₂₁ , W ₂₂ , W ₂₃ , ... W _2b
...
W _a1 , W _a2 , W _a3 , ... W _ab
The output of the weighting circuit 21 is as follows.
W ₁₁ * (sYe ₁₁ , sCy ₁₁ , sG ₁₁ , sMg ₁₁ ), W ₁₂ * (sYe ₁₂ , sCy ₁₂ , sG ₁₂ , sMg ₁₂ ), ... W _1b * (sYe _1b , sCy _1b , sG _1b , sMg _1b )
W ₂₁ * (sYe ₂₁ , sCy ₂₁ , sG ₂₁ , sMg ₂₁ ), W ₂₂ * (sYe ₂₂ , sCy ₂₂ , sG ₂₂ , sMg ₂₂ ), ... W _2b * (sYe _2b , sCy _2b , sG _2b , sMg _2b )
...
W _a1 * (sYe _a1 , sCy _a1 , sG _a1 , sMg _a1 ), W _a2 * (sYe _a2 , sCy _a2 , sG _a2 , sMg _a2 ), ... W _ab * (sYe _ab , sCy _ab , sG _ab , sMg _ab )

The exposure evaluation value generation circuit 22 receives the output of the weighting circuit 21, adds the weighted integral value of each block for each color, and then adds the weighted value according to each color, thereby adding the exposure evaluation value Yexp. Is generated as follows. Note that k _ye1, k _cy1, k _{g1, and km mg1} are weighting coefficients for each color (Ye, Cy, G, Mg).

Yexp = k _ye1 * ΣsYe + k _cy1 * ΣsCy + k _g1 * ΣsG + k _mg1 * ΣsMg
ΣsYe = W ₁₁ * sYe ₁₁ + W ₁₂ * sYe ₁₂ + ... + W _1b * sYe _1b + W ₂₁ * sYe ₂₁ + ... + W _2b * sYe _2b + ... + W _ab * sYe _ab
ΣsCy = W ₁₁ * sCy ₁₁ + W ₁₂ * sCy ₁₂ + ... + W _1b * sCy _1b + W ₂₁ * sCy ₂₁ + ... + W _2b * sCy _2b + ... + W _ab * sCy _ab
ΣsG = W ₁₁ * sG ₁₁ + W ₁₂ * sG ₁₂ + ... + W _1b * sG _1b + W ₂₁ * sG ₂₁ + ... + W _2b * sG _2b + ... + W _ab * sG _ab
ΣsMg = W ₁₁ * sMg ₁₁ + W ₁₂ * sMg ₁₂ + ... + W _1b * sMg _1b + W ₂₁ * sMg ₂₁ + ... + W _2b * sMg _2b + ... + W _ab * sMg _ab

The setting of (k _ye1, k _cy1, k _g1, k _mg1 ) in air is ( _{0.25, 0.25, 0.25,} 0.25)
When complementary colors (Ye, Cy, G, Mg) are expressed as primary color components (R, G, B),
Yexp = 0.25 * ΣsYe + 0.25 * ΣsCy + 0.25 * ΣsG + 0.25 * ΣsMg
= 0.25 * ΣsR + 0.5 * ΣsG + 0.25 * ΣsB
Can be expressed as

The formula for converting complementary colors (Ye, Cy, G, Mg) to primary colors (R, G, B) is
“Ye = 0.5R + 0.5G”, “Cy = 0.5G + 0.5B”, “G = G, Mg = 0.5R + 0.5B”.

As described above, the coefficient for generating the exposure evaluation value in air is set, whereas when the coefficient is set in water, the red component ratio of the light source decreases and the blue component ratio increases. In _addition, the setting of (k _ye1, k _cy1, k _g1, k _mg1 ) is (0.1, 0.3, 0.3, 0.3) and the complementary colors (Ye, Cy, G, Mg) are based on the primary colors (R, G, B) In terms of ingredients,
Yexp = 0.1 * ΣsYe + 0.3 * ΣsCy + 0.3 * ΣsG + 0.3 * ΣsMg
= 0.2 * ΣsR + 0.5 * ΣsG + 0.3 * ΣsB
And set.

  The above-described embodiment is a case where one image sensor has a plurality of color filters. However, the above-described embodiment is also effective in a system in which a plurality of image sensors have different color filters.

(Another embodiment according to the present invention)
In the above-described embodiment, whether the shooting environment is underwater or in the air is determined using a button for selecting whether the environment is underwater or in the air.
In underwater photography, a waterproof case 40 as shown in FIGS. 4A and 4B is attached to the imaging device 50. At this time, a mechanism for detecting the mounting of the waterproof case 40 is provided, and by detecting the mounting, it is determined whether it is underwater or in the air, and the weight coefficient of each color in the exposure evaluation value generation circuit 22 is automatically switched. .

Further, a water pressure sensor (not shown) may be mounted to determine whether the water is in water or in air.
Further, although the CPU 14 generates a weighting coefficient for the integral value of each block, the generation weighting coefficient may be stored in the ROM as a lookup table. By doing so, it is only necessary to refer to the table with respect to the integration value calculated by the integration circuit, and the processing in the CPU is not required, so that the processing speed is increased.

  Each means constituting the imaging device 50 and each step of the imaging method in the embodiment of the present invention described above can be realized by operating a program stored in a RAM or ROM of a computer. This program and a computer-readable recording medium recording the program are included in the present invention.

  In addition, the present invention can be implemented as a system, apparatus, method, program, storage medium, or the like, and can be applied to a system composed of a plurality of devices. Moreover, you may apply to the apparatus which consists of one apparatus.

  In the present invention, a software program (in the embodiment, a program corresponding to the flowchart shown in FIG. 3) for realizing the functions of the above-described embodiment is directly or remotely supplied to the system or apparatus, and the system Or the case where it is achieved also by the computer of the apparatus reading and executing the supplied program code is included.

  Accordingly, since the functions of the present invention are implemented by computer, the program code installed in the computer also implements the present invention. In other words, the present invention includes a computer program itself for realizing the functional processing of the present invention.

  In that case, as long as it has the function of a program, it may be in the form of object code, a program executed by an interpreter, script data supplied to the OS, and the like.

  As a recording medium for supplying the program, for example, floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, MO, CD-ROM, CD-R, CD-RW, magnetic tape, nonvolatile memory card ROM, DVD (DVD-ROM, DVD-R) and the like.

  As another program supply method, a client computer browser is used to connect to an Internet homepage, and the computer program itself of the present invention or a compressed file including an automatic installation function is downloaded from the homepage to a recording medium such as a hard disk. Can also be supplied.

  It can also be realized by dividing the program code constituting the program of the present invention into a plurality of files and downloading each file from a different homepage. That is, a WWW server that allows a plurality of users to download a program file for realizing the functional processing of the present invention on a computer is also included in the present invention.

  In addition, the program of the present invention is encrypted, stored in a storage medium such as a CD-ROM, distributed to users, and key information for decryption is downloaded from a homepage via the Internet to users who have cleared predetermined conditions. It is also possible to execute the encrypted program by using the key information and install the program on a computer.

  In addition to the functions of the above-described embodiments being realized by the computer executing the read program, the OS running on the computer based on the instructions of the program is used for the actual processing. The functions of the above-described embodiment can be realized by performing some or all of the processes.

  Furthermore, after the program read from the recording medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion board or The CPU or the like provided in the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

1 is a block diagram illustrating a schematic configuration of an imaging apparatus according to an embodiment of the present invention. It is a block diagram showing the example of a structure of a photometry evaluation circuit. It is a flowchart explaining operation | movement of the imaging device of embodiment. It is a figure showing the waterproof case for imaging devices of an embodiment, (a) shows a mode that an imaging device is stored in a waterproof case, and (b) is a figure showing a state where an imaging device was stored in a waterproof case. .

Explanation of symbols

1 Optical system 2 Aperture device 3 CCD
4 CDS / A / D circuit 5 TG circuit 6 Data bus 7 Storage device (memory)
8 Integration Circuit 9 Photometric Evaluation Circuit 10 Signal Processing Circuit 11 Compression Circuit 12 Recording Medium 13 Strobe Device 14 CPU
15 Operation unit 40 Waterproof case 50 Imaging device

Claims (12)

An imaging device having an imaging device equipped with a plurality of color filters,
Photographing environment determining means for determining whether the environment for photographing with the image sensor is in the air or in water;
Exposure evaluation value calculating means for calculating an exposure evaluation value for evaluating an exposure state of a video signal output from an image sensor corresponding to the plurality of color filters;
Photographing means for determining and photographing an exposure condition from the exposure evaluation value calculated by the exposure evaluation value calculating means;
The exposure evaluation value calculating means includes weighting means for applying a weighting coefficient for each color to the output of the image sensor on which the plurality of color filters are mounted,
The weighting means changes the weighting coefficient for each color according to the shooting environment determined by the shooting environment determination means.   2. The imaging apparatus according to claim 1, wherein the weighting unit increases the ratio of the blue weighting coefficient when photographing underwater than when photographing in air.   The imaging apparatus according to claim 1, wherein the imaging environment determination unit determines the environment by detecting attachment of a waterproof case of the imaging apparatus. Furthermore, it has a water pressure sensor,
The imaging apparatus according to claim 1, wherein the imaging environment determination unit determines the environment by detecting a water pressure with the water pressure sensor. Having storage means;
The imaging apparatus according to claim 1, wherein the weighting coefficient is stored in advance in the storage unit as a table. An image pickup method having an image pickup device on which a plurality of color filters are mounted,
A shooting environment determination step of determining whether an environment for shooting with the image sensor is in the air or underwater;
An exposure evaluation value calculating step for calculating an exposure evaluation value for evaluating an exposure state of a video signal output from an image sensor corresponding to the plurality of color filters;
A photographing step of photographing by setting an exposure condition from the exposure evaluation value calculated by the exposure evaluation value calculating step;
The exposure evaluation value calculating step includes a weighting step of applying a weighting factor for each color to the output of the image sensor on which the plurality of color filters are mounted,
In the weighting step, the weighting coefficient for each color is changed in accordance with the shooting environment determined in the shooting environment determination step.   The imaging method according to claim 6, wherein in the weighting step, the ratio of the blue weighting factor is increased during underwater photographing than during air photographing.   The imaging method according to claim 6, wherein the imaging environment determination step determines the environment by detecting attachment of a waterproof case of the imaging device.   The imaging method according to claim 6, wherein the imaging environment determination step determines the environment by detecting a water pressure with a water pressure sensor.   The imaging method according to claim 6, wherein the weighting coefficient is stored in advance in a storage unit as a table. A computer program for causing a computer to execute an imaging method having an imaging device having a plurality of color filters mounted thereon,
A shooting environment determination step of determining whether an environment for shooting with the image sensor is in the air or underwater;
An exposure evaluation value calculating step for calculating an exposure evaluation value for evaluating an exposure state of a video signal output from an image sensor corresponding to the plurality of color filters;
A photographing step of photographing by setting an exposure condition from the exposure evaluation value calculated by the exposure evaluation value calculating step;
The exposure evaluation value calculating step includes a weighting step of applying a weighting factor for each color to the output of the image sensor on which the plurality of color filters are mounted,
In the weighting step, a computer program causing a computer to execute an imaging method for changing a weighting factor for each color in accordance with a shooting environment determined in the shooting environment determination step.   A computer-readable recording medium having recorded thereon the computer program according to claim 11.

Images