JP2006054525A - Imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To attain an imaging apparatus which is good under various conditions. <P>SOLUTION: Whether a battery voltage is more than a predetermined voltage, whether a strobe voltage is less than a predetermined value, whether an underwater protector is mounted, etc. are judged. A pixel adding flag is set, based on the judgment result. And, whether the pixel adding flag is set is judged (S61). When the pixel adding flag is set, a CCD drive pattern for pixel adding photographing is set (S62). Consequently, even when, for example, a strobe luminance cannot be performed and exposure is insufficient, a photographed image of proper brightness can be acquired. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an imaging apparatus such as a camera.

  Conventionally, in a digital camera using a CCD image sensor or the like as an image sensor, an image signal obtained from the CCD image sensor is obtained when the brightness of the subject decreases, such as when the subject to be photographed is changed from outdoor to indoor. A captured image having a desired brightness is obtained by changing the amplification factor of the amplifier to be amplified.

However, when the brightness of the subject is insufficient, increasing the amplification factor of the image signal amplifies the noise, thereby degrading the image quality of the captured image.
In order to solve such a problem, for example, Patent Document 1 describes that a signal charge having the number of pixels corresponding to the signal level of an image signal is added from a CCD sensor and output.
JP-A-10-150601

  In the invention described in Patent Document 1, the signal charges of the pixels are added according to the signal level of the image signal output from the image sensor. However, in many cases, sufficient quality images cannot be obtained. In the above invention, for example, when the flash photography is performed in a state where the battery voltage is lowered, there arises a problem that the battery voltage is further lowered and the battery life of the digital camera is shortened.

  An object of the present invention is to obtain a good captured image under various conditions.

  The imaging device of the present invention includes an imaging unit, a light emitting unit that irradiates a subject, an imaging device state determining unit that determines a state of the imaging device, and light emission of the light emitting unit based on a determination result of the imaging device state determining unit. Pixel addition operation determining means for determining whether or not to perform an operation and whether or not to add pixels of the imaging means.

Another aspect of the imaging apparatus of the present invention includes a driving condition setting unit that sets a driving condition for the imaging unit based on a determination result of the pixel addition determination unit.
According to another aspect of the imaging apparatus of the present invention, when the imaging state determination unit determines that the power state of the imaging apparatus has not reached a predetermined state, the pixel addition determination unit adds the pixels of the imaging unit. I do.

Another aspect of the imaging apparatus of the present invention includes a driving condition setting unit that sets a driving condition for the imaging unit based on a determination result of the pixel addition determination unit.
In another aspect of the imaging apparatus of the present invention, the imaging state determination unit includes a peripheral device mounting detection unit that detects whether or not a peripheral device is mounted on the imaging device, and the peripheral device mounting detection unit detects the imaging device. When it is detected that a peripheral device is attached to the camera, the pixel addition determining unit adds pixels obtained by the photographing unit.

In another aspect of the imaging apparatus of the present invention, the peripheral device attachment detection means detects whether or not a body protector requiring underwater photography is attached.
In another aspect of the imaging apparatus of the present invention, the peripheral device mounting detection means detects whether or not a focal length changing adapter lens is mounted.

  In another aspect of the imaging apparatus of the present invention, the imaging apparatus state determination unit detects a strobe charging voltage for causing the strobe to emit light, and the imaging apparatus state determination unit determines that the strobe charging voltage is less than a predetermined voltage. In this case, the pixel addition determining unit adds pixels obtained by the imaging unit.

  According to the present invention, since it is determined whether or not to perform the light emission of the light emitting means and the addition of the pixels according to the state of the imaging device, it is possible to obtain a good captured image under various conditions. For example, when the remaining amount of the battery is low, by adding pixels without performing the light emitting operation, it is possible to reduce battery consumption and obtain a good captured image.

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an example of the basic configuration of the present invention.
In FIG. 1, an imaging apparatus state determination unit 1 determines whether or not the battery voltage of an imaging apparatus (digital camera or the like) is a predetermined value or more, whether or not a strobe charging voltage is a predetermined value or more, whether or not a peripheral device is attached, and the like. to decide.

The pixel addition operation determination unit 2 determines whether or not to add pixels, whether or not to perform strobe light emission, based on the determination result of the imaging device state determination unit 1.
The image pickup means 3 is composed of, for example, a CCD sensor and converts charges accumulated in each image pickup device into image signals.

Next, FIG. 2 is a block diagram of the imaging apparatus (digital camera) 10 according to the embodiment, and FIGS. 3A and 3B are external perspective views thereof.
In FIG. 2, the camera control unit 11 includes an imaging device state determination unit 1 and a pixel addition operation determination unit 2.

  The release switch 12 is provided in the upper part of the main body as shown in FIG. 3, and is in a state where the switch is pushed in one step (first release) according to a user operation or a state where the switch is pushed further in (second second). A signal indicating release is output to the camera control unit 11.

The strobe setting unit 13 sets strobe light emission conditions and the like, and is set by the operation switch 31 on the back side of the camera 10 shown in FIG.
The stereo charging voltage determination unit 14 determines whether or not the charging voltage of the strobe light emission circuit unit 15 is less than a predetermined voltage, and outputs the determination result to the imaging device state determination unit 1. The strobe light emitting circuit unit 15 supplies power for light emission to the strobe light emitting unit 16.

The battery check unit 17 determines whether or not the voltage of the battery 18 is less than a predetermined value, and outputs the determination result to the imaging device state determination unit 1.
The peripheral device attachment detection unit 19 is provided on the side surface of the photographing lens 32 shown in FIG. 3, detects whether or not a waterproof protector or a focal length changing adapter lens is attached to the photographing lens 32, and the detection result is obtained. The image is output to the imaging device state determination means 1. The peripheral device attachment detection unit 19 is configured by, for example, a switch and is turned on or off when the peripheral device is attached, and outputs a signal indicating the state at that time.

  The strobe charge state notifying unit 20 is a display unit that indicates whether or not the strobe light emitting circuit unit 15 has been charged. As shown in FIG. 3B, the LED provided on the right side of the finder 41 is turned on. The state of charge is displayed by color. For example, the LED lights red when charging is incomplete, and lights green when completed.

  The battery warning notification unit 21 is a display that warns of a decrease in the voltage of the battery 18, and the state of charge is displayed as the shape of the battery on the liquid crystal display unit 36 on the back side of the imaging device 10 in FIG.

  The timing generator (TG) driver 5 supplies a timing signal for driving the image pickup means (CCD) 3 to the AFE processing unit 33 under the control of the camera control unit 11 and also supplies a timing signal for driving to the mechanical shutter controller 37. Supply.

  The AFE processing unit 33 performs control for driving the CCD sensor 3 and also performs CDS (Correlated Double Sampling) for reducing the noise of the signal output from the CCD sensor 3 and AGC (Automatic Gain Control) for stabilizing the signal level. After performing such processing, ADC (Analog to Digital Converter) processing for converting an analog signal into digital data is performed, and the converted digital data is output as photographed image data.

  The camera DSP 34 corrects brightness / saturation / saturation / tint, etc., when reproducing and displaying the captured image data stored in the SDRAM 35 or recording the captured image data in the SDRAM 35, etc., γ correction, color processing, WB (White balance) correction processing or the like is performed on the captured image data.

A liquid crystal display (LCD) 36 is provided on the back side of the imaging device 10 and displays an image currently captured by the photographing lens 32, an image recorded in a memory or the like, a menu, and the like.
3A and 3B are external perspective views of the imaging apparatus 10. FIG. As shown in FIG. 3A, a photographing lens 32 is provided in the center on the front side of the imaging apparatus 10, and a strobe light emitting unit 16 and a finder 41 are provided in the upper right part.

A release switch 12 is provided on the upper side surface of the imaging device 10, and a memory card insertion slot 42 is provided on the left side surface when viewed from the front.
As shown in FIG. 3 (B), a finder 41, a strobe charging state notification unit 20, an autofocus indicator 43, and a zoom switch 44 are provided on the upper back side of the imaging device 10, and in the center of the main body. A liquid crystal display unit 36 is provided, and an operation switch 31 for setting an operation mode and the like is provided on the right side thereof.

  Next, the operation of the imaging apparatus 10 configured as described above will be described with reference to the flowcharts of FIGS. The following processing is executed by a CPU (not shown) of the imaging apparatus 10.

When the power supply of the imaging apparatus 10 is turned on, initialization processing is first executed (FIG. 4, S1), and then it is determined whether or not the power switch is turned on (S2).
When the power switch is on (S2, YES), the process proceeds to step S3, and pre-first-release camera setting processing is executed. When the power switch is off (S2, NO), the detection of whether or not the power switch in step S2 is on is repeated.

If the camera setting process before the first release is completed, it is next determined whether or not the release switch 12 is in the first release state (S4).
When the release switch 12 is in the first release state (S4, YES), that is, when the user presses the release switch 12 one step for shooting, the process proceeds to step S5 to execute AE and AF processing, and the focus is set in the next step S6. Drive the lens.

  On the other hand, when the release switch 12 is not in the first release state (S4, NO), that is, when the user is not operating the release switch 12, the process returns to step S2 to determine whether or not the power switch is on.

After step S6, it is determined whether or not the release switch 12 is in the second release state (S7).
If it is determined that the release switch 12 is not in the second release state (S7, NO), the process proceeds to step S8, and it is determined again whether or not the release switch 12 is in the first release state.

If it is determined in step S8 that the release switch 12 is in the first release state (S8, YES), the determination of whether or not the second release state is in step S7 is repeated.
If it is determined in step S8 that the release switch 12 is not in the first release state (S8, NO), the process returns to step S2 because the release switch 12 has been released.

  In step S7, when it is determined that the release switch 12 is in the second release state (S7, YES), the process proceeds to step S9 to execute the photographing process, and normal photographing or pixel addition photographing is performed according to the state of the imaging device 10. Then, the photographed image data is written to the image card (memory card) (S10), and the photographed image data is displayed on the liquid crystal display unit 36 (S11). Then, it returns to step S2.

Here, the camera setting process before the first release in step S3 of FIG. 4 will be described with reference to the flowcharts of FIGS.
First, it is determined whether or not the zoom switch 44 has been operated (FIG. 5, S21). If the zoom switch 44 is operated (S21, YES), the process proceeds to step S22, and the zoom lens is driven to enlarge or reduce the image.

  When the zoom switch 44 is not operated (S21, NO), or after step S22, the process proceeds to step S23 to determine whether or not the shooting mode is set (or changed).

If the shooting mode is set (or changed) (S23, YES), the process proceeds to step S24 to set the set (or changed) shooting mode.
When the shooting mode is not set (or changed) (S23, NO), or when the shooting mode is set (or changed) in step S24, the strobe charging voltage is checked in step S25, and in the next step S26. It is determined whether or not the strobe charging voltage is less than a predetermined voltage.

When the strobe charging voltage is less than the predetermined voltage (S27, YES), the process proceeds to step S27 to determine whether or not the shooting mode is the strobe off mode.
If the shooting mode is not the strobe off mode (S27, NO), the strobe is charged in step S28, and the strobe charging flag f_stchg is set to “1” in the next step S29. Further, the strobe charging state notification unit 20 is notified that charging is in progress (S30).

When the strobe charging voltage is equal to or higher than the predetermined voltage in step S26 (S26, YES), the process proceeds to step S31 to determine whether or not the strobe is being charged.
When the charging voltage is equal to or higher than the predetermined voltage and the strobe is being charged, or when it is determined that the strobe is off in step S27, the process proceeds to step S32 and charging of the strobe is stopped. Then, the strobe charging flag f_stchg is cleared. Further, the flash charging state notification unit 20 turns off the notification during charging. Thereafter, the process proceeds to A of FIG. 6 to execute the process of step S35.

In step S35 of FIG. 6, it is determined whether or not the peripheral device mounting detection unit 19 detects the mounting of the peripheral device (FIG. 6, S35).
If it is detected that the peripheral device is attached to the imaging device 10 (S35, YES), the process proceeds to step S36, where the underwater protector or the teleconverter (focal length changing adapter) is attached. Is determined.

  Whether the installed peripheral device is an underwater protector or a teleconverter may be determined by making the structure of the detection switch of the peripheral device mounting detection unit different for each peripheral device, or the same The detection mechanism may have a structure in which the pressing force of a switch or the like varies depending on peripheral devices, and the detection voltage varies accordingly.

  When the underwater protector or the teleconverter is attached to the imaging apparatus 10 (S36, YES), the process proceeds to step S37, and “1” is set to the underwater protector attachment flag f_wtprt or the teleconverter attachment flag f_telecon. Thereafter, the process proceeds to step S39 in FIG.

  If it is determined in step S35 that the peripheral device is not attached (S35, NO), or if it is determined in step S36 that the underwater protector and the teleconverter are not attached (S36, NO), the process proceeds to step S38. Then, the underwater protector mounting flag f_wtprt and the teleconverter mounting flag f_telecon are cleared. Thereafter, the process proceeds to step S39 in FIG.

In step S39 in FIG. 7, the battery voltage is checked. Then, in the next step S40, it is determined whether or not the battery voltage is equal to or higher than a predetermined voltage.
When the battery voltage is lower than the predetermined voltage (S40, NO), the process proceeds to step S41, the battery warning flag f_btwn is set to “1”, and the battery warning notification is turned on in step S42 (S42).

By the above processing, for example, a warning is displayed that the battery voltage has dropped due to a change in the display of part of the battery mark indicating the state of charge of the battery 18 of the liquid crystal display unit 36.
If it is determined in step S40 that the battery voltage is equal to or higher than the predetermined voltage (S40, YES), the process proceeds to step S43, the battery warning flag f_btwn is cleared, and the battery warning notification is turned off in step S44.

Next, the pixel addition flag f_pixadd is cleared in step S45. In the next step S46, it is determined whether or not the strobe charging flag f_stchg is “1”.
When it is determined in step S46 that the strobe charging flag f_stchg is “0” (S46, NO), the process proceeds to the next step S47, and it is determined whether or not the underwater protector mounting flag f_wtprt is “1”.

  When it is determined in step S47 that the underwater protector mounting flag f_wtprt is “0” (S47, NO), the process proceeds to the next step S48, where it is determined whether or not the teleconverter mounting flag f_telecon is “1”.

  When the teleconverter mounting flag f_telecon is determined to be “0” in step S48 (S48, NO), the process proceeds to step S49, and it is determined whether or not the battery warning flag f_btwn is “1”.

  If any one of the strobe charging flag f_stchg, the underwater protector mounting flag f_wtprt, the teleconverter mounting flag f_telecon, and the battery warning flag f_btwn is determined to be “1” in the determination processing in steps S46 to S49 (S46 to S49). If any of SS49 is YES), the process proceeds to step S50, and the pixel addition flag f_pixadd is set to “1”.

  When the strobe voltage is less than the predetermined voltage, the underwater protector is attached to the imaging device 10, the teleconverter is attached, or the battery voltage is less than the predetermined voltage by the processing in step S50 described above, the pixel An addition flag f_pixadd is set. When the pixel addition flag f_pixadd is set, pixel addition of the CCD sensor 3 is performed in the photographing process of FIG. 9 described later.

  Here, pixel addition of the CCD sensor 3 will be described with reference to FIG. FIGS. 8A and 8B are explanatory diagrams of pixel addition in the CCD sensor 3 in the Bayer array. In the Bayer array CCD sensor 3, G pixels are arranged in a staggered pattern, and R pixels and B pixels are arranged therebetween.

  In the case of addition of four pixels in FIG. 8A, for example, when the target pixel is a B pixel, the charges of the four pixels of the adjacent B pixel on the left and right of the target pixel and the adjacent B pixel on the upper and lower sides of the target pixel are The value added to the charge is output from the CCD sensor 3 as the pixel value of the target pixel.

  8B, for example, when the target pixel is an R pixel, right and left adjacent R pixels, upper and lower adjacent R pixels, and diagonal left and right directions A value obtained by adding nine adjacent R pixels to the target pixel is output as the pixel value of the target pixel.

Next, the contents of the photographing process in step S9 in FIG. 4 will be described in detail with reference to the flowchart in FIG.
First, it is determined whether or not the pixel addition flag f_pixadd is “1” (FIG. 9, S61).

  When the pixel addition flag f_pixadd is “1” (S61, YES), the process proceeds to step S62, and a CCD drive pattern for pixel addition photographing is set. Further, the shutter speed (Tv: time value) and aperture value (Av: aperture value) corresponding to pixel addition are recalculated (S63).

  On the other hand, when it is determined in step S61 that the pixel addition flag f_pixadd is “0” (S61, NO), the process proceeds to step S64, and a CCD driving pattern for normal photographing that does not perform pixel addition is set.

If the CCD drive pattern is determined, photographing is started by the CCD sensor 3 in step S65.
Next, it is determined whether or not to perform strobe light emission (S66). In this process, it is determined whether or not to perform strobe light emission according to the measured brightness of the subject image, operation mode, battery voltage, and the like.

  When the battery voltage and strobe voltage are equal to or higher than the predetermined voltage and the strobe light emission is necessary (S66, YES), the process proceeds to step S67, where the drive voltage is supplied to the strobe light emitting unit 16 to emit light.

  Even when the strobe light emission mode is set, the strobe light emission is not performed when the battery voltage is less than a predetermined value or the strobe voltage is not charged and the pixel addition flag f_pixadd is set.

  Next, it is determined whether or not a predetermined exposure time has elapsed (S68). When the predetermined exposure time has not elapsed (S68, NO), the exposure time determination process in step S68 is continued.

  When the predetermined exposure time has elapsed (S68, YES), the process proceeds to step S69, the mechanical shutter is closed, and the photographing by the CCD sensor 3 is terminated. Then, the pixel information of the third field from the first field of the CCD sensor 3 is read in order (S70).

  In the processing of step S70, pixel information corresponding to the charge of each pixel is read in normal shooting, and in pixel addition shooting, a value obtained by adding charges of a plurality of pixels, for example, a value obtained by adding 9 pixels is used as pixel information. read out.

  Image processing such as white balance adjustment and edge processing is performed on the normal captured image or the pixel-added captured image, and the processed image data is stored in the SDRAM 35 or the like (S71). Further, the normal photographed image or the pixel addition photographed image is displayed on the liquid crystal display unit 36 (S72).

  According to the above-described embodiment, by performing pixel addition according to the state of the imaging device 10, for example, when the remaining amount of the battery 18 is low, even if the shooting conditions require strobe light emission, the strobe light emission is performed. By performing pixel addition without performing this, it is possible to obtain a captured image with a brightness of a predetermined level or higher. Furthermore, when the remaining amount of the battery 18 is low, shooting is performed without performing the flash emission, thereby extending the life of the battery 18 and extending the possible shooting time compared to shooting using the flash. .

Even when the strobe is not charged, by performing pixel addition, it is possible to obtain a good captured image even in a state where exposure is insufficient, so that the shooting timing is not missed.
Furthermore, when the waterproof protector is attached to the image pickup apparatus 10 and the strobe cannot be used, or when the subject distance may be insufficient because the focal length change adapter is attached to shoot a long distance, By performing the addition, a captured image with appropriate luminance can be obtained.

The present invention is not limited to the embodiment described above, and may be configured as follows, for example.
(1) In the embodiment, the case where charges of a plurality of pixels are added in the transfer path of the CCD sensor 3 has been described. However, the output of the CCD sensor 3 is converted into digital data, and the digital data is added to add the pixels. May be performed.
(2) The CCD sensor 3 is not limited to one using a Bayer array filter, and may be another CCD sensor or an image sensor other than a CCD.
(3) The present invention is not limited to the method of sequentially reading out pixels in the first to third fields as in the embodiment, but can be applied to other reading methods such as reading out pixels in even and odd fields.
(4) The present invention is not limited to shooting still images, but can also be applied to shooting moving images.

It is explanatory drawing of an example of the basic composition of invention. It is a circuit block diagram of the imaging device of an embodiment. It is an external view of an imaging device. It is a flowchart which shows the operation | movement of the whole imaging device. It is a flowchart of the camera setting process before the first release. It is a flowchart of the camera setting process before the first release. It is a flowchart of the camera setting process before the first release. It is explanatory drawing of pixel addition. It is a flowchart of an imaging process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Imaging device state determination means 2 Pixel addition operation determination means 3 Imaging means 5 Timing generator driver 10 Imaging device 11 Shooting control unit 14 Strobe charging voltage determination unit 16 Strobe light emission unit 17 Battery check unit 18 Battery 19 Peripheral device attachment detection unit 36 Liquid crystal Display section

Claims (7)

Imaging means;
Light emitting means for illuminating the subject;
Imaging device state determining means for determining the state of the imaging device;
An image pickup apparatus comprising: a pixel addition operation determination unit that determines whether to perform a light emission operation of the light emission unit and whether to perform pixel addition of the image pickup unit based on a determination result of the image pickup device state determination unit.   The imaging apparatus according to claim 1, further comprising a driving condition setting unit that sets a driving condition of the imaging unit based on a determination result of the pixel addition determining unit.   3. The imaging according to claim 1, wherein when the imaging state determination unit determines that the power state of the imaging apparatus has not reached a predetermined state, the pixel addition determination unit determines to perform pixel addition. apparatus. The photographing state determination means includes peripheral device attachment detection means for detecting whether or not a peripheral device is attached to the imaging device,
The imaging according to claim 1, 2, or 3, wherein the pixel addition determining means determines to add a pixel when the peripheral apparatus mounting detection means detects that a peripheral device is mounted on the imaging apparatus. apparatus.   The imaging apparatus according to claim 4, wherein the peripheral device attachment detection unit detects whether or not an underwater photographing protector is attached.   The imaging apparatus according to claim 4, wherein the peripheral device mounting detection unit detects whether or not a focal length changing adapter is mounted. The imaging apparatus according to claim 1, wherein the pixel addition determination unit determines to perform pixel addition when the imaging apparatus state determination unit determines that a strobe charging voltage for causing the strobe to emit light is less than a predetermined voltage.

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