KR20070070010A - Image pickup apparatus and method of photographing - Google Patents

Abstract

An image pickup apparatus and an image pickup method are provided to capture both an image by using a strobo and an image without using the strobo through one-time photographing operation. An image pickup apparatus includes an exposure time acquisition unit, an image pickup unit(108), an image combiner(120), and a light source(144). The image pickup unit divides an exposure time acquired by the exposure time acquisition unit into n exposure time periods, continuously captures n images with the divided exposure time period, and then captures a single image with the divided exposure time period. The image combiner combines the images captured by the image pickup unit. The light source emits light at least once at photographing timing of an image to illuminate an object.

Description

Image pickup apparatus and method of photographing

1 is an explanatory diagram showing a configuration of an imaging device according to a first embodiment of the present invention.

2 is an explanatory diagram for explaining a data structure stored in a memory according to the first embodiment of the present invention.

3 is a flowchart showing a photographing method according to the first embodiment of the present invention.

4 is an explanatory diagram showing a relationship between a focal length of a lens and a camera shake limit shutter speed according to the first embodiment of the present invention.

5 is an explanatory diagram for explaining a photographing method according to the first embodiment of the present invention.

6 is an explanatory diagram for explaining a photographing method according to the first embodiment of the present invention.

7 is an explanatory diagram for explaining a photographing method according to the first embodiment of the present invention.

8 is a flowchart showing a photographing method according to a second embodiment of the present invention.

9 is an explanatory diagram for explaining a photographing method according to the second embodiment of the present invention.

10 is an explanatory diagram for explaining a photographing method according to the second embodiment of the present invention.

It is explanatory drawing for demonstrating the conventional imaging method.

Brief description of symbols for the main parts of the drawings

100: imaging device 108: CCD element

114: image input controller 116: image signal processing circuit

118: image coincidence detection circuit 120: image synthesizing circuit

122: compression processing circuit 123: LCD driver

124: LCD 126: timing generator

128: first CPU 130: second CPU

132: control panel 133: shutter button

134: memory 140: recording media

144: flash unit

TECHNICAL FIELD The present invention relates to an imaging apparatus and a photographing method, and more particularly, to an imaging apparatus and a photographing method for photographing a plurality of images by dividing an exposure time in one photographing operation.

When strobe photography is performed while shooting a person indoors or outdoors at night, the background is underexposed even when the subject is properly exposed, and the background is dark even when the subject such as the person is bright.

To solve this problem, a slow synchro is known that slows down the shutter speed when shooting stroboscopically to capture both the subject and the background brightly. The slow synchro has two functions, a "front curtain synchro" that emits strobes immediately after the shutter is opened, and a "thick curtain synchro" that emits strobes immediately before the shutter closes.

By applying this method, a technique for obtaining an effect such as a slow synchro by synthesizing a photographed image without emitting strobe and a photographed image by emitting strobe light when capturing one or a plurality of images is disclosed.

Further, Japanese Patent Laid-Open No. 2000-069352 discloses a technique of capturing a plurality of images continuously in time, extracting a feature amount of the photographed image, and synthesizing the images according to the feature amounts to obtain an appropriate image. have.

Japanese Patent Laid-Open Publication No. 2003-153287 discloses a technique for combining both an image which does not emit strobe and an image which emits strobe, and photographs both a subject and a background in a good state.

However, these methods can only photograph images in which the subject is illuminated when the strobe is made to emit light. Even when the strobe was made to emit light, there was a problem in that it was not possible to capture both an image illuminated and a non-illuminated image by a single shooting operation.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object of the present invention is to provide a novel and improved imaging apparatus and a photographing method capable of capturing both an image that emits strobe light and an image that does not emit strobe light in one shooting operation. It is.

According to one aspect of the present invention, an exposure time acquisition unit that obtains an exposure time at the time of photographing and an exposure time A obtained by dividing n (n is an integer of 1 or more) by an exposure time A acquired by the exposure time acquisition unit in one imaging operation. an imaging unit which continuously photographs n images at / n, and then continuously photographs one image at an exposure time A / n, an image synthesis unit which synthesizes a plurality of images photographed by the imaging unit, An image pickup apparatus is provided, comprising a light source that emits light at least once at a shooting timing of a certain image to illuminate a subject.

According to this configuration, the exposure time acquisition unit acquires the exposure time of the subject in one shooting operation, and divides the obtained exposure time by n to capture n + 1 images at exposure time A / n. At least one of the n + 1 images is an image in which the subject is brightly illuminated by light emission from a light source. As a result, according to the imaging device which concerns on one aspect of this invention, it is possible to image both the image which the light from the light source was reflected on the subject, and the image which was not reflected by a single shooting operation.

N + 1 images may be taken when shooting to emit light, and n images may be taken when shooting that does not emit light. According to such a configuration, the number of images to be photographed changes depending on whether light sources are emitted. As a result, the photographing pattern can be changed only by the light emission of the light source without preparing a plurality of photographing modes.

When taking a picture that emits a light source, the light source can be made to emit light only at the time of shooting of the first sheet or the n + 1th sheet. With this configuration, the same effect as that of the front curtain synchro can be obtained when the light source is emitted only during the first shooting, and the same effect as the thick film synchro when the light source is emitted only during the shooting of the n + 1 shot. .

When photographing the light source to emit light, when the light source emits light, the n-th image of the 1st to nth sheets and / or the nth image of the 2nd to n + 1th sheets can be synthesized by the image combining unit. With such a configuration, it is possible to obtain an image photographed by emitting a light source by one photographing operation, and an image of either or both of images captured without emitting a light source.

When photographing without emitting a light source, the n-th image of the 1st to nth sheets can be synthesized by the image combining unit.

The image recording unit may further include an image recording unit for recording the 1-n-th n-th images synthesized by the image synthesizing unit and / or the n-th image of the 2-n + 1 th-image. With this configuration, an image taken without emitting a light source can be obtained. With such a configuration, a plurality of images before synthesis can be freely processed or synthesized after photographing.

When synthesizing a plurality of images in the image synthesizing unit, the gain correction of the amount of light may be performed. With such a configuration, even when the amount of light is insufficient due to division of the exposure time, the amount of light can be supplemented by performing gain correction.

In order to solve the above problems, according to another aspect of the present invention, an exposure time after taking n images by the exposure time A / n obtained by dividing the exposure time A by n (n is an integer of 1 or more) in one shooting operation When photographing one image with A / n and shooting to emit a light source, the light source is emitted only at the first or n + 1th photographing, and the first to nth images and / or 2 to When the n-th image of the n + 1 sheet is synthesized and the photographing is performed without emitting the light source, the n-th image of the 1st to nth sheets is synthesized. By this method, it is possible to obtain either or both images of an image in which light from a light source is projected onto a subject by one shooting operation and an image in which light is not to be shined from the light source.

When synthesizing n images, the gain correction of the amount of light can be performed. With such a configuration, even when the amount of light is insufficient due to division of the exposure time, the amount of light can be supplemented by performing gain correction.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has a substantially same functional structure, the same code | symbol is attached | subjected and the duplicate description is abbreviate | omitted.

Conventionally, as shown in Fig. 11, a plurality of images shot by a plurality of shooting operations are synthesized, or by dividing the exposure time, a plurality of images are taken by one shooting operation (one shutter button operation) and the plurality of images are taken. Disclosed are a photographing method for correcting the shaking of an image generated at the time of photographing or increasing the resolution of the image by synthesizing the images.

In the present embodiment, an imaging apparatus and a photographing method capable of photographing an image having various special effects as well as correcting a shake of an image generated at the time of photographing by a single photographing operation will be described.

1 is an explanatory diagram showing an imaging device according to a first embodiment of the present invention. As shown in FIG. 1, the imaging apparatus 100 according to an embodiment of the present invention includes a zoom lens 102, an aperture 104, a focus lens 106, and a charge coupled device (CCD) device 108. And an integrated CDS (Correlated Double Sampling) circuit 110, an A / D converter 112, an image input controller 114, an image signal processing circuit 116, and an image coincidence detection circuit 118. And an image synthesizing circuit 120, a compression processing circuit 122, an LCD (Liquid Crystal Display) driver 123, an LCD 124, a timing generator 126, and a first CPU (Central Processing Unit). 128, the second CPU 130, the operation unit 132, the shutter button 133, the memory 134, the VRAM (Video Random Access Memory) 136, and the media controller 138 And a recording medium 140, motor drivers 142a, 142b, and 142c, a flash device 144, and a vertical and horizontal sensor 146.

In the present embodiment, the imaging unit is configured using the CCD element 108. However, the present invention is not limited to this example, and a Complementary Metal Oxide Semiconductor (CMOS) element may be used instead of the CCD element 108. As shown in FIG. Since the CMOS element can convert the image light of the subject into an electrical signal at a higher speed than the CCD element, it can shorten the time from photographing the subject to performing the image combining process.

The zoom lens 102 photographs by changing the size of the subject with a lens in which the focal length is continuously changed by moving back and forth in the optical axis direction. The diaphragm 104 adjusts the amount of light entering the CCD element 108 when the image is taken. The focus lens 106 adjusts the focus of the subject by moving back and forth in the optical axis direction.

The timing generator 126 is for inputting a timing signal to the CCD element 108. The shutter speed is determined by the timing signal from the timing generator 126. That is, the driving of the CCD element 108 is controlled by the timing signal from the timing generator 126, and the electric signal which becomes the basis of the image data by injecting the image light from the subject within the time that the CCD element 108 is driven. Is generated.

The CCD element 108 is an element for converting light incident from the zoom lens 102, the aperture 104, and the focus lens 106 into an electrical signal. In this embodiment, the time for drawing the electric signal by controlling the incident light by the electronic shutter is adjusted. The time for drawing the electric signal by controlling the incident light may be adjusted by using the mechanical shutter.

The CDS circuit 110 is a circuit in which a CDS circuit, which is a kind of sampling circuit for removing noise of an electrical signal output from the CCD element 108, and an amplifier for amplifying the electrical signal after removing noise, are integrated. In the present embodiment, the imaging device 100 is configured by using a circuit in which the CDS circuit and the amplifier are integrated, but the CDS circuit and the amplifier may be configured as separate circuits.

The A / D converter 112 converts the electrical signal generated by the CCD element 108 into a digital signal to generate raw data of an image.

The image signal processing circuit 116 is a circuit for adjusting gain correction and white balance of the amount of light with respect to the electric signal output from the CCD element 108 or the image synthesized by the image synthesizing circuit 120.

The image coincidence detection circuit 118 includes a function of the hand shake detection unit and is a circuit for detecting the position of the same subject among a plurality of images captured.

The image synthesizing circuit 120 is an example of an image synthesizing unit, and is a circuit for synthesizing a plurality of photographed images. The method of synthesizing the images may be automatically determined according to the surrounding situation at the time of shooting, or may be determined by the setting of the photographer. In addition, the image matching circuit 118 may detect the positions of the same subjects among the plurality of images and combine the plurality of images in the image synthesizing circuit 120 so that the positions coincide with each other.

The compression processing circuit 122 performs compression processing to compress the image synthesized by the image combining circuit 120 into image data of an appropriate format. The compression of the image may be a reversible format or an irreversible format. Examples of suitable formats include the Joint Photographic Experts Group (JPEG) or JPEG2000 format. In addition, the image signal processing circuit 116 may perform gain correction or white balance adjustment before the compression processing circuit 122 performs the compression processing.

The LCD 124 performs live viewer display before the shooting operation, display of various setting screens of the imaging device 100, display of captured images, and the like.

The first CPU 128 is a CPU for performing a signal system command to the CCD element 108, the CDS circuit 110, or the like, and the second CPU 130 is for performing a command of the operation system for the operation of the operation member. CPU. In addition, the first CPU includes the functions of the photometric result acquisition unit, the focal length acquisition unit, and the shooting condition determination unit, and the first CPU includes the functions of the shift amount acquisition unit. In the present embodiment, the first CPU 128 and the second CPU 130 are separate components, but one CPU may be used to execute a signal system command and an operation system command.

The operation unit 132 is disposed with a member for performing an operation of the imaging device 100. The operation unit 132 includes a function as a shift amount setting unit for setting a shift amount when synthesizing a plurality of images. On the member disposed on the operation unit 132, a power button, a cross key for selecting a shooting mode, a shift amount and a shift direction, a select button, and the like are disposed. The set shift amount is acquired by the second CPU 130 at the time of shooting, and shifts and synthesizes a plurality of images based on the shift amount and the shift direction acquired by the second CPU 130 at the time of image synthesis.

The LCD 124 includes a function as a shift amount display unit, and can confirm the shift amount and the shift direction set by the operation unit 132. The display of image data or various information of the imaging device 100 on the LCD 124 is performed through the LCD driver 123.

The operation unit 132 not only shifts or shifts, but also rotates and synthesizes the image, and enlarges or reduces the image to enlarge or reduce and synthesizes the image by changing the brightness. The amount of change in brightness at the time may be set. Such a configuration makes it possible to more reproduce the shooting intention of the photographer.

The shutter button 133 is an example of a switch unit. By operating the shutter button 133 to be in an activated state, for example, the shutter button 133 is photographed by pressing the shutter button 133.

The memory 134 is an example of an image storage section, which temporarily stores a photographed image or an image synthesized by the image synthesizing circuit 120. The memory 134 has a storage capacity enough to store a plurality of images. Read / write of an image to the memory 134 is controlled by the image input controller 114.

2 is an explanatory diagram schematically showing a memory map of the memory 134. The number of sheets that can be stored depends on the capacity of the memory 134 and the size of the image. In FIG. 2, it is shown that it has a storage capacity enough to store four captured images and three synthesized images. Types of memory may include dynamic random access memory (DRAM), synchronous DRAM (SDRAM), and double data rate SDRAM (DDR SDRAM).

The VRAM 136 retains the contents displayed on the LCD 124, and the resolution and the maximum number of colors of the LCD 124 depend on the capacity of the VRAM 136.

The recording medium 140 is an example of an image recording unit that records a photographed image or a synthesized image. Input / output to the recording medium 140 is controlled by the media controller 138. The recording medium 140 may be a memory card that is a card-type storage device for recording data in a flash memory.

The motor drivers 142a, 142b, and 142c control the motor for operating the zoom lens 102, the aperture 104, and the focus lens 106. The zoom lens 102, the aperture 104, and the focus lens 106 are operated by the motor drivers 142a, 142b, and 142c to adjust the size of the subject, the amount of light, and the focus.

The flash device 144 is an example of a light source, and is used to brighten a subject when shooting outdoors at night or in a dark place. When performing flash photography, a light emission command is performed from the first CPU 128 to the flash device 144, and the flash device 144 emits light by the light emission command from the first CPU 128, and the flash device 144 The subject is brightened by the light emitted by). In addition, the vertical and horizontal sensors 146 detect the shooting vertical and horizontal directions when shooting in the imaging device 100.

Next, the flow of the image capturing method in the image capturing apparatus according to the first embodiment of the present invention will be described with reference to FIGS. 1 and 3.

When shooting an image, the photographer first presses the shutter button 133. When the shutter button 133 is pressed, the signal from the shutter button 133 is supplied to the second CPU 130, and the photographing process is started.

The second CPU 130 receiving the signal from the shutter button 133 supplies a signal to the first CPU 128 to notify that the shutter button 133 is pressed. The first CPU 128 receiving the signal acquires the focal length information of the focus lens 106 and the metering result information of the subject (S110). From the metering result information of the subject, the shutter speed necessary for shooting only one image in one shooting operation can be derived.

When the first CPU 128 acquires the focal length information of the focus lens 106 and the photometric result information of the subject, the exposure time and the number of shots per sheet of the image are determined from the acquired information (S120). It is determined whether the exposure time per sheet of the image obtained as a result of the metering of the subject is greater than or equal to the camera shake limit shutter speed (S130). If the exposure time per image obtained as a result of metering the subject is greater than or equal to the camera shake limit shutter speed, the exposure time per sheet is set to be less than or equal to the camera shake limit shutter speed, which is the longest shutter speed at which the subject can be taken without shaking. 4 is an explanatory diagram showing a relationship between a focal length of a lens and a camera shake limit shutter speed. As shown in Fig. 4, the camera shake limit shutter speed can be found to be approximately 1 / f (seconds) when the focal length of the focus lens 106 is f (mm).

A plurality of images are taken in the obtained exposure time per sheet (S140). Here, a case in which the focal length of the focus lens 106 is 50 mm will be described as an example. The camera shake limit shutter speed is approximately 1/50 = 0.02 seconds. As a result of metering the subject, when the shutter speed is 0.2 seconds, 10 images are taken at the shutter speed of 0.02 seconds. In this case, 11 or more shots may be taken at a shutter speed of 0.02 seconds. As a result, it is possible to capture an image with a higher resolution as a whole than when shooting in a normal manner. In addition to obtaining the number of copies from the shutter speed, the number of sheets may be set in advance, and the shutter speed per sheet may be obtained from the number of copies. When the number of shots of an image is set to 20, the shutter speed per sheet becomes 0.01 second.

When the exposure time per sheet does not match the shutter speed set in advance by the imaging device 100, the shutter speed is set at the shutter speed set in advance by the imaging apparatus 100 closer to the exposure time per sheet, which is faster than the exposure time per sheet. The lack of the exposure amount of the image is compensated for by the increase of the gain. For example, as a result of metering a subject, when the shutter speed is 1/30 second, when the number of shots of the image is set to eight, the shutter speed per sheet is 1/240 second. However, depending on the imaging device 100, the shutter speed may not be set to an arbitrary value. For example, when the shutter speed set in the imaging device 100 is 1/125 second and 1/250 second, the shutter speed may not be set to 1/240 second. In such a case, the shutter speed is set to 1/250 second which is a faster shutter speed than 1/240 second, and eight images are taken at the shutter speed 1/250 second. Since the exposure amount of the image is insufficient, the lack of the exposure amount of the image is corrected by performing gain correction of the amount of light in the image signal processing circuit 116.

On the other hand, when the exposure time per sheet obtained as a result of metering the subject is less than the camera shake limit shutter speed, only one shot is photographed without division of the exposure time (S160). That is, when the shutter speed obtained as a result of metering the subject in the above example is 0.02 seconds or less, only one shot is taken without dividing the exposure time.

Image light of the subject is input to the CCD element 108 according to the number of shots determined by the second CPU 130 and the exposure time per sheet. The image light of the subject passes through the zoom lens 102, the aperture 104, and the focus lens 106 and is irradiated onto the CCD element 108. The image light of the irradiated subject is converted into an electrical signal by the CCD element 108.

When the image light of the subject is converted into an electrical signal in the CCD device 108, the CDS circuit 110 removes noise included in the electrical signal generated by the CCD device 108 and simultaneously amplifies the electrical signal. The amplified electrical signal is converted into a digital signal by the A / D converter 112 and image data is generated. The image data converted into digital signals is stored in the memory 134 by the image input controller 114.

The memory 134 stores all the image data shot by one shooting operation. When the sum of the capacities of the image data of the plurality of shot images exceeds the storage capacity of the memory 134, the memory 134 is stored. The number of images until the capacity reaches the upper limit is stored. For example, when shooting of 10 images is determined by the second CPU, but only the capacity of 9 pieces of image data can be stored in the memory 134, nine images are taken. Since the total exposure amount is insufficient, the lack of the exposure amount may be compensated for by the extension of the shutter speed, or may be compensated by performing the gain correction of the light amount in the image signal processing circuit 116.

When shooting is completed and the image is stored in the memory 134, the image is synthesized using the image (S160). A plurality of images may be synthesized as they are, a method of synthesizing a plurality of images so that the positions of the subjects coincide, a method of shifting and synthesizing a plurality of images evenly, and a method of randomly shifting and synthesizing a plurality of images. The composition is synthesized by at least one of a method of enlarging or reducing a plurality of images, a method of rotating and synthesizing a plurality of images, and a method of changing and combining brightness of a plurality of images.

The method of composing the image may be determined by the photographer in advance, or may be automatically selected depending on the circumstances around the image. In addition, the synthesis | combination in one imaging | photography may be carried out only once, and you may synthesize | combine 2 or more times by another synthesis method.

When synthesizing a plurality of images by a method in which the positions of the subjects coincide with each other, before the image synthesizing circuit 120 synthesizes the images, the image coincidence detecting circuit 118 detects the deviation of the same subject among the plurality of images. Based on the misalignment degree, the image synthesizing circuit 120 synthesizes the positions of the differences, for example, as the subjects, as shown in Fig. 5A. As a result, when a method of synthesizing a plurality of images so that the positions of the subjects coincide as a compositing method, it is possible to generate a synthesized image in which the effects of hand shake are suppressed.

When combining a plurality of images by a method of randomly shifting and synthesizing, the second CPU 130 randomly determines the shift amount and the shift direction and synthesizes them based on the shift amount and the shift direction.

When synthesizing by changing and combining the brightness of a plurality of images, the second CPU 130 determines the amount of change in the brightness of the image and based on the amount of change, as shown in FIG. Synthesize by changing the brightness. The amount of change in brightness may be set by the photographer by operating the operation unit 132 or may be determined in advance.

When synthesizing the plurality of images by the method of enlarging or reducing the images, the second CPU 130 acquires the enlargement amount or the reduction amount, and based on the enlargement amount or the reduction amount, as shown in FIG. 5C, For example, synthesized by enlarging or reducing the difference of the subject. The enlargement amount or reduction amount may be set by the photographer operating the operation unit 132 or may be determined in advance.

In the case of synthesizing by rotating and synthesizing a plurality of images, the second CPU 130 acquires an amount of rotation and based on the amount of rotation, as shown in FIG. Synthesize The amount of rotation may be set by a photographer operating the operation part 132, or may be predetermined. The center of rotation may be the center of the image or may be set by the photographer by operating the operation unit 132.

When synthesizing a plurality of images by the method of shifting and synthesizing evenly, as shown in FIG. 6, for example, a doll as a subject is fixed in a predetermined direction based on the shift amount and the shift direction acquired by the second CPU 130. Synthesize by shifting to equally.

In the case of synthesizing the plurality of images as they are, the image synthesizing circuit 120 simply adds the plurality of images and synthesizes the golf putt so as to know, for example, the golf putt.

The synthesized image obtained by combining the plurality of images is stored in the memory 134. When there is room in the capacity of the memory 134, not only a composite image by one synthesis but also a composite image by a plurality of synthesis may be stored. With such a configuration, it is possible to generate a composite image by a plurality of synthesis methods in one shooting operation.

The synthesized image stored in the memory 134 performs a compression process in which the compression processing circuit 122 compresses the image data into an appropriate format. The compression of the image may be a reversible format or an irreversible format. As an example of a suitable format, you may convert to JPEG or JPEG2000 format. In addition, gain correction and white balance adjustment may be performed in the image signal processing circuit 116 before the compression processing in the compression processing circuit 122.

The synthesized image subjected to the compression processing in the compression processing circuit 122 is displayed on the LCD 124. The composite image is displayed on the LCD 124 and the composite image is recorded on the recording medium 140. When a synthesized image is generated by synthesizing the images by a plurality of methods, all the synthesized images may be recorded, the synthesized image may be switched by an operation of the operation unit 132, and the synthesized result may be confirmed on the LCD 124.

As described above, according to the image capturing apparatus and the photographing method according to the present embodiment, it is possible to photograph a synthesized image by one or two or more image compositing methods in one photographing operation.

In the above, the imaging flow of the image in the imaging device which concerns on 1st Example of this invention was demonstrated with reference to FIG.

Next, an image capturing apparatus and a photographing method according to a second embodiment of the present invention will be described with reference to FIGS. 1, 8 and 9.

The components of the imaging device according to the present embodiment are substantially the same as those of the imaging device 100 according to the first embodiment. Only specific processing of the first CPU 128 and the second CPU 130 is different. With reference to FIG. 1, the structure of the imaging device which concerns on a present Example is demonstrated.

The first embodiment is an imaging apparatus and a photographing method for photographing a plurality of images in one photographing operation. The second embodiment is an application example of the first embodiment, in which a plurality of images are taken by one shooting operation, and the flash device is fired at the time of capturing the image to shoot the captured image and the flash without emitting the flash. An imaging device and a photographing method for obtaining both of images.

When performing normal strobe shooting, first, the operation unit 132 is operated to set the shooting mode to strobe shooting. Then, the photographing process of the image is started by the photographer operating the shutter button 133. When the shutter button 133 is pressed, the signal from the shutter button 133 is supplied to the second CPU 130, and the photographing process is started. In general stroboscopic imaging, when the shutter button is pressed, a signal from the shutter button is supplied to the second CPU 130, and the second CPU 130 notifies that the stroboscopic imaging has been performed on the first CPU 128.

Upon receiving the notification, the first CPU 128 notifies the motor drivers 142a, 142b, and 142c, the timing generator 126, and the flash device 144 that stroboscopic imaging has been performed. The notified motor drivers 142a, 142b, and 142c control the operation of the zoom lens 102, the aperture 104, and the focus lens 106 to set the appropriate focal length or aperture value, and the first CPU 128. Causes the flash device 144 to emit light, and the timing of the incident of the image light from the subject to the CCD element 108 by the timing generator 126 is determined, and imaging of the image is performed only once. The above is the operation of the imaging device 100 when performing normal stroboscopic imaging.

In the stroboscopic imaging method according to the present embodiment, a plurality of images are taken by dividing the exposure time by one shooting operation, and the flash device 144 is emitted by taking pictures in accordance with the exposure time per sheet.

In the stroboscopic imaging method according to the present embodiment, first, the operation unit 132 is set to set the shooting mode to be capable of stroboscopic imaging. Then, the photographer presses the shutter button 133 to start the image capturing process. In addition to the method in which the photographer sets the shooting mode, setting of a shooting mode for performing stroboscopic shooting automatically detects a situation (for example, a dark room or a nighttime outdoor light) and automatically performs stroboscopic shooting. Can be set to

When the shooting mode is set to be capable of stroboscopic imaging according to the operation of the operation unit 132, the operation unit 132 is operated to set at what timing the flash device 144 emits light. The light emission timing of the flash device 144 may be set at the time of shooting any image in accordance with the exposure time per sheet, in addition to the time of shooting the first image or the shooting of the last image. The number of times of light emission may be one or two or more times.

The second CPU 130 receiving the signal from the shutter button 133 supplies a signal to the first CPU 128 to notify that the shutter button has been pressed. The first CPU 128 supplied with the signal acquires the exposure time A in one shooting operation, the number of shots n (n is an integer of 1 or more), and the light emission timing information of the flash device 144 ( S210). The predetermined number of shots may be a predetermined number of shots, or the number of shots may be determined by operating the operation unit 132.

The first CPU 128 includes a function as an exposure time acquisition unit. When the exposure time A and the number of shots n are acquired in one shooting operation, the exposure time A is divided by n and the exposure time per sheet is A /. Set to n (S220). In operation S230, the first CPU 128 determines whether or not the flash photographing mode is performed. In order to perform n + 1 shots, a signal for photographing n + 1 images at an exposure time A / n per sheet is sent to the timing generator 126, and the CCD element 108 receives image light from a subject. Let it enter. The image light of the subject passes through the zoom lens 102, the aperture 104, and the focus lens 106 and is irradiated onto the CCD element 108. The image light of the irradiated subject is converted into an electrical signal by the CCD element 108.

Here, when capturing n + 1 images, the flash unit 144 emits light upon capturing the first image or the last image based on the emission timing information of the flash unit 144 acquired by the first CPU 128. (S250). For example, when the flash unit 144 is set to emit light at the time of capturing the first image by the operation of the operation unit 132, the flash unit 144 emits light at the same timing as the capturing of the first image. When the flash device 144 is set to emit light at the time of photographing the last image, the flash device 144 emits light at the same timing as photographing the n + 1th image.

9A is an explanatory diagram showing a histogram indicating the brightness of a subject, and FIG. 9B is an explanatory diagram showing photographing timing when photographing n + 1 images. In normal photography, the exposure time A is determined according to the metering result of the subject. In this embodiment, the exposure time A / n is determined by dividing the predetermined exposure time A by n according to the photometric result of the subject, and n + 1 images are taken at the exposure time A / n. At the time of shooting an image, as shown in Fig. 9B, the metering may be performed for every single shooting, or the metering may be performed only for the first shooting.

In FIG. 9B, the case where the flash device 144 emits light at the time of photographing the last n + 1 sheets is described. When photographing the last n + 1 sheets, pre-emission is performed when the subject is metered, and the flash device 144 emits light when the subject is exposed to thereby photograph an image in which the subject is brightly lit. As shown in Fig. 9A, the photometric result histogram of the subject is almost the same as the result of adding the histogram of each image when the photographing is performed by dividing the exposure time.

10 is an explanatory diagram for explaining the photographing method according to the second embodiment of the present invention. In FIG. 10, the first to nth images indicate that the images are taken without emitting the flash device 144, and the last n + 1 images cause the flash device 144 to emit light so as to brighten the difference as the subject. Indicates one image.

When the image light of the subject in the CCD device 108 is converted into an electrical signal, the CDS circuit 110 removes the noise generated by the CCD device 108 and amplifies the signal generated by the CCD device 108. The D converter 112 converts the digital signal. The image data converted into digital signals is stored in the memory 134 by the image input controller 114.

The memory 134 stores all the image data shot by one shooting operation. When the sum of the image data capacities of the plurality of photographed images exceeds the storage capacity of the memory 134, the number of images until the capacities of the memory 134 reaches the upper limit is stored. For example, even if the number of shots acquired by the second CPU is 10, when the capacity of only nine pieces of image data can be stored in the memory 134, nine images are taken. Since the total exposure amount is insufficient, the shortage of the exposure amount may be supplemented by the extension of the shutter speed, or may be compensated by performing the gain correction of the light amount in the image signal processing circuit 116.

When the photographing is completed and the plurality of photographed images are stored in the memory 134, the image synthesizing circuit 120 synthesizes the plurality of images. The synthesis of the images combines the 1st to nth images and the 2nd to n + 1th images to generate two kinds of synthesized images (S260). When synthesizing the images, the image signal processing circuit 116 may perform gain correction of the amount of light. The lack of the exposure amount that may be caused by the division of the exposure time can be compensated for by the gain correction of the light amount in the image signal processing circuit 116.

For example, when n + 1 shots are taken with the setting for causing the flash device 144 to emit light at the time of shooting the first image, n + 1 shots and n + 1 shots from the second shot are taken. By combining, two kinds of synthesized images can be generated. As a result, two kinds of images can be obtained in which the flash device 144 is photographed by emitting light, and the subject is brightly photographed, and the normal image photographed without emitting the flash device 144. At this time, the image photographed by emitting the flash device 144 becomes an image having the same effect as the front curtain synchro.

Also, a setting for causing the flash device 144 to emit light at the time of capturing the last image, even when n + 1 shots are taken, is equivalent to a setting for causing the flash device 144 to emit light at the time of capturing the first image. Similarly, two types of synthesized images can be generated by combining the first to nth images and the second to n + 1th images. As a result, two types of images can be obtained: an image in which the flash device 144 is emitted and photographed so that a subject is brightly photographed, and a normal image photographed without emitting the flash device 144. In addition, the image photographed by emitting the flash device 144 at that time becomes an image having the same effect as the thick film synchro.

In the present embodiment, when synthesizing a plurality of images in the image synthesizing circuit 120, a plurality of images including an image photographed by emitting the flash device 144 and an image except an image that emits the flash device 144. Are synthesized to generate two kinds of synthesized images. However, only the images photographed by emitting the flash device 144 may be synthesized.

If it is determined in S230 that the first CPU 128 is a mode in which flash photography is not performed, n images are taken at an exposure time A / n (S270). Then, the photographing operation as described above is performed and n images are synthesized by the image synthesizing circuit 120 (S280). Even when shooting without flash photography, the image signal processing circuit 116 may correct the gain of the light amount when synthesizing the images. By dividing the exposure time, a shortage of the exposure amount may occur, but the shortage of the exposure amount can be compensated for by the gain correction of the light amount in the image signal processing circuit 116.

Before synthesizing the images in the image synthesizing circuit 120, the image coincidence detecting circuit 118 detects the degree of misalignment of the same common object among the plurality of images, and the image synthesizing circuit 120 determines the degree of misalignment based on the degree of misalignment. You may synthesize | combine so that a position may correspond. As a result, the image which suppressed the influence by the camera shake can be produced.

The generated two synthesized images are stored in the recording medium 140, and the compression processing circuit 122 performs compression processing of the images and converts them into image data of an appropriate format. The compression of the image may be a reversible format or an irreversible format. In the case of the reversible format, the compressed image data can be completely restored. In the case of an irreversible format, image data can be compressed small. Examples of suitable formats include the JPEG and JPEG2000 formats.

In addition, gain correction or white balance adjustment may be performed in the image signal processing circuit 116 before the compression processing in the compression processing circuit 122. With such a configuration, it is possible to correct the deterioration of the image quality caused by the division of the exposure time.

Two composite images subjected to compression processing in the compression processing circuit 122 are displayed on the LCD 124. By operating the operation unit 132, the synthesized image can be changed and displayed. The order to be displayed on the screen may first display a composite image including an image taken by emitting the flash device 144, or may first display a composite image including no image taken by emitting the flash device 144. .

Two composite images subjected to compression processing in the compression processing circuit 122 can be recorded on the recording medium 140. Any composite image may be recorded on the recording medium 140 or both may be recorded. When recording any one composite image, after displaying the composite image on the LCD 124, the composite image to be recorded is selected by the operation of the operation unit 132, and the selected composite image is recorded on the recording medium 140. You may also

As described above, according to the imaging apparatus and the imaging method according to the second aspect of the present invention, it is possible to capture both an image in which strobe is emitted and an image in which the strobe is not emitted by one shooting operation, and further, effects such as slow synchro can be obtained. The branch can take an image.

As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, this invention is not limited to this example. It will be apparent to those skilled in the art that various changes or modifications can be made within the scope of the technical idea described in the claims, and that they naturally belong to the technical scope of the present invention. .

For example, the captured image and the generated composite image are compressed by the compression processing circuit 122 and then displayed on the LCD 124 or recorded on the recording medium 140. The compression processing circuit 122 performs compression. It may be displayed on the LCD 124 without performing it, or may be recorded on the recording medium 140 without performing compression in the compression processing circuit 122.

The novel and improved imaging device and imaging method according to the present invention can take both an image in which strobe is emitted and an image in which strobe is not emitted by one shooting operation.

Claims (9)

An exposure time acquisition unit for acquiring an exposure time at the time of photographing; After photographing n images continuously by the exposure time A / n obtained by dividing the exposure time A obtained by the exposure time acquisition unit by one imaging operation by n (n is an integer of 1 or more), the exposure time A / an imaging unit which photographs one image with n; An image synthesizing unit for synthesizing the plurality of images photographed by the imaging unit; And And a light source that emits light at least once at an imaging timing of any one of the images to illuminate the subject. According to claim 1, And n + 1 images are taken when shooting to emit the light source, and n images are taken when shooting that does not emit the light source. The method of claim 2, And a light source to emit light only at the time of photographing the first sheet or the n + 1 sheet when photographing the light source. The method of claim 3, wherein When photographing for emitting the light source, when the light source emits light, the image combining unit synthesizes the n-th image of 1 to n sheets and / or the n-th image of 2 to n + 1 sheets in the image combining unit. Device. The method of claim 2, When photographing without emitting the light source, the n-th image of the 1st to nth sheets is synthesized by the image combining unit. The method according to any one of claims 2 to 5, And an image recording unit for recording the n-th images of the 1 to n sheets and / or the n-th images of the 2 to n + 1 sheets synthesized by the image synthesizing unit. According to claim 1, And the gain correction of the amount of light when synthesizing the plurality of images in the image synthesizing unit. After taking n images by the exposure time A / n divided by the exposure time A by n (n is an integer of 1 or more) in one shooting operation, one image is taken by the exposure time A / n, When shooting to emit a light source, the light source is emitted only at the first or n + 1th shot, and the 1st to nth n images and / or the 2 to n + 1th n images are synthesized. , When photographing without emitting a light source, the n-th image of the 1st to nth sheets is synthesized. The method of claim 8. And a gain correction of the amount of light when synthesizing the n images.

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