JP5036599B2 - Imaging device - Google Patents

Description

  The present invention relates to an imaging apparatus, and in particular, by changing the amount of blur and changing the depth of field in a pseudo manner according to the focal length and zoom position of a zoom lens, the enlargement magnification of a digital zoom, and the pseudo focal length. The present invention relates to an imaging apparatus capable of obtaining a telephoto effect such as a silver salt camera or a photographing effect that cannot be obtained with a silver salt camera.

  In portrait photography and macro photography such as flowers, it is effective to use photographic expressions that highlight the main subject by intentionally blurring the foreground or background. When performing such photographic expression, focus on the main subject and shoot with the depth of field shallow, but the depth of field in this case depends on optical elements such as the aperture and focal length of the lens. Will be decided.

On the other hand, in a digital camera, particularly a compact type digital camera, the exposure surface of the image sensor is significantly narrower than the exposure surface (film surface) of the silver halide camera. For this reason, when trying to obtain the same angle of view as the silver salt camera, the focal length of the imaging lens of the digital camera becomes shorter than the focal length of the imaging lens of the silver salt camera. In addition, since a photographic lens having a large aperture is large and expensive, a photographic lens having a small aperture is often used in a compact digital camera.
It is well known that the depth of field becomes deeper and less blurred when the focal length is small and the aperture is small. Therefore, digital cameras, especially compact type digital cameras, have a deeper depth of field than silver halide cameras, and are often not good at photographic expressions with a shallow depth of field and a large amount of blur. .

As a technique for solving the above weaknesses of digital cameras, there is, for example, Patent Document 1.
Patent Document 1 includes a focus adjustment lens, a photographing unit, a control unit, a blur detection unit, an image division unit, and a blur enhancement unit, and the control unit has a main subject within the range of depth of field. Adjust the focus position to a position that fits inside and is not in focus. Thereafter, the blur detection unit separates the image data into the main subject and the background, further enhances the blur amount of the background according to the blur amount of the background, and obtains a photographic expression that is as natural as possible (first). Embodiment). Furthermore, as a second embodiment, a method for reducing the amount of calculation is proposed, and as a third embodiment, a technique for naturally blurring not only the background but also the foreground is proposed.

JP 2007-124398 A

By the way, in the camera system of the above-mentioned Patent Document 1, the objective is to obtain as natural a blur as possible. For this purpose, the focus lens is deliberately moved from the just-focus position so that the main subject is at the last part of the depth of field. Set the offset and optically blur the background as much as possible, and change the blur amount added / emphasized by image processing according to the blur amount, so that the blur is larger when the original blur amount is large. If it is small, a process of blurring is performed.
Although natural blur according to the original amount of blur can be obtained, blur is emphasized according to the focal length and zoom position of the zoom lens, or even blur is added according to the enlargement ratio and pseudo focal length of the digital zoom. There is no effect of changing or emphasizing the effect or photographic expression (such as blurring more widely on the wide-angle side than on the telephoto side) that could not have been possible with a silver halide camera. Furthermore, no solution has been proposed for the problem of realizing a photographic expression that has not been possible before, which changes or emphasizes the telephoto effect of a zoom lens or digital zoom.

  The present invention is for solving the above-described problems of the prior art, and its purpose is to change the amount of blur according to the focal length and zoom position of the zoom lens, the enlargement magnification and the pseudo focal length of the digital zoom, It is an object of the present invention to provide an imaging apparatus that can obtain a telephoto effect like a silver salt camera or a photographing effect that cannot be obtained with a silver salt camera by artificially varying the depth of field.

In order to achieve this object, the invention described in claim 1 includes a zoom lens capable of changing a focal length,
Zoom lens control means for controlling the focal length of the zoom lens;
Subject image separation means for separating the main subject portion area of the subject image captured through the zoom lens and the zoom lens control means and the region other than the main subject portion;
A blur amount control unit capable of blurring a region other than the main subject portion separated by the subject image separation unit and changing a blur amount;
If you change the focal length or the zoom lens position of the zoom lens, have a, a blurring amount changing means for changing the amount of blur that is an output from the blurring amount control means,
The blur amount changing means controls the blur amount to be decreased as the focal length of the zoom lens increases or the zoom lens position approaches the telephoto position. is there.

The invention according to claim 2 is an imaging lens;
A digital zoom processing means for obtaining an image as if the focal length was changed in a pseudo manner by electrically processing a subject image captured by the imaging lens;
Subject image separation means for separating a main subject portion area of a subject image captured through the imaging lens and the digital zoom processing means and a region other than the main subject portion;
A blur amount control unit capable of blurring a region other than the main subject portion separated by the subject image separation unit and changing a blur amount;
If you change the magnification or pseudo focal length of the digital zoom by the digital zoom processing unit, have a, a blurring amount changing means for changing the amount of blur that is an output from the blurring amount control means,
The blur amount changing unit is an imaging apparatus that controls to reduce the blur amount in accordance with an increase in the digital zoom magnification by the digital zoom processing unit or an increase in the pseudo focal length. is there.

Further, the subject image separating means separates the main subject portion area and the area other than the main subject portion into a foreground area and a background area, and the blur amount control means includes: 3. The image pickup apparatus according to claim 1, wherein control is performed so as to blur only the foreground area of the area other than the main subject portion .
Further, in the invention according to claim 4, the subject image separating unit separates the main subject portion region and the main subject portion region into a foreground region and a background region,
The imaging apparatus according to claim 1, wherein the blur amount changing unit controls the blur amount of the foreground region to be smaller than that of the background region .

Further, the invention according to claim 5 further includes shooting mode setting means for setting various shooting modes, and display means for displaying the subject image.
In the shooting mode setting for performing blur control by the blur amount control means, it has blur control temporary release means that can temporarily add and release blur control when checking the blur processing status before shooting. The imaging apparatus according to claim 1 or 2.
The invention of claim 6, wherein, in a state of operating the blurring control temporary release means, by performing photographing, imaging according to claim 5, characterized in that it comprises a means for performing photography is not carried out blurring processing Device.

Here, the “issue” and “solution” of the present invention will be clarified.
"Task"
In the case of digital cameras with optical zoom, especially compact type digital cameras, the focal length of the optical system is small because the imaging surface is small compared to silver halide cameras, so the depth of field is small, like a silver halide camera. Photographic effect (for example, a photographic effect in which only a person is raised in portrait photography or the like) cannot be obtained.
In the case of a compact digital camera that does not have an optical zoom, there is a model that has a so-called digital zoom function. In the digital zoom function, a part of the original image is cut out and enlarged. For this reason, if the original image is not blurred, the blur amount remains the same except for enlargement of the blur amount due to enlargement. It is not possible to obtain a shooting effect that makes only a person rise.

"Solution"
The imaging device of the present invention includes a zoom lens, a zoom control unit, an imaging unit (which is naturally provided as an imaging device), and a captured image separation unit. The captured subject image is placed in a main subject and other areas. To separate. For areas other than the separated main subject, the telephoto effect is enhanced by changing the blur amount according to the focal length or zoom position of the zoom lens, or a shooting effect that could not be implemented with a silver salt camera was added. To do. In the case of a configuration having a digital zoom function without a zoom lens, the same effect can be obtained by changing the blur amount in accordance with the enlargement magnification of the digital zoom or the pseudo focal length.
Note that Patent Document 1 is similar to the present invention in that a subject image is mainly separated into a main subject and a background, and predetermined image processing is performed on the background region to change the blur amount. However, the present invention is different based on what the blur amount is changed, and the purpose and effect are also different.

  According to the first aspect of the present invention, the zoom lens that can change the focal length, the zoom lens control unit that controls the focal length of the zoom lens, and the zoom lens and the zoom lens control unit. A subject image separation unit that separates a region of a main subject portion of a subject image from a region other than the main subject portion, a region other than the main subject portion separated by the subject image separation unit is blurred, and a blur amount is changed. The zoom lens includes a possible blur amount control unit and a blur amount change unit that changes a blur amount that is an output from the blur amount control unit when a focal length or a zoom lens position of the zoom lens is changed. When the focal length or zoom position is changed, the blur amount for blur control can be changed.

  According to the second aspect of the present invention, the image pickup lens and the digital zoom processing means for obtaining an image as if the focal length was changed in a pseudo manner by electrically processing the subject image picked up by the image pickup lens, A subject image separation unit that separates a region of a main subject portion of a subject image captured through the imaging lens and the digital zoom processing unit from a region other than the main subject portion, and the main image separated by the subject image separation unit. The blur amount control means that can blur the area other than the subject portion and change the blur amount, and the digital zoom processing means when the digital zoom magnification or pseudo focal length is changed, the output from the blur amount control means Since there is a blur amount changing means for changing a certain blur amount, if the magnification of the digital zoom or the pseudo focal length is changed, You can change the blurring amount that lend control.

Further, according to the first aspect of the invention, the blurring amount changing means or the focal length of the zoom lens becomes large, or the zoom lens position in response to approach the telephoto position, the blurring amount small fence Therefore, it is possible to increase / decrease the blur amount to be controlled in proportion to the change of the zoom position.

Further, according to the second aspect of the invention, the blurring amount changing means, the or magnification of the digital zoom by the digital zoom processing unit increases, or in response to the pseudo focal length increases, the blurring amount small fence Therefore, it is possible to increase or decrease the blur amount to be controlled in proportion to the enlargement magnification of the digital zoom.
According to a fifth aspect of the present invention, in the imaging apparatus according to the first or second aspect, the photographing apparatus further includes photographing mode setting means for setting various photographing modes and display means for displaying the subject image, and the blurring is performed. When setting the shooting mode to perform blur control by the amount control means, it has blur control temporary release means that can temporarily add and release blur control when checking the blur processing status before shooting, so blur before shooting Shooting results can be predicted while switching the presence or absence of the blur amount to be controlled.

According to the invention described in claim 6, in the imaging apparatus according to claim 5 , since the photographing control is performed in a state in which the blur control temporary canceling unit is operated, the photographing is performed without performing the blurring process. Whether or not the shooting mode uses blur amount switching for blur control can be easily switched immediately before shooting.

  As a summary of the effects, the above-described configuration makes it possible to enhance the telephoto effect and to perform shooting that could not be performed with a silver halide camera, regardless of whether or not a zoom lens is mounted, and is easy to use. Can be realized.

Hereinafter, the present invention will be described based on the illustrated embodiments.
<< First Embodiment >>
<Configuration>
FIG. 1 shows the configuration of a digital still camera device and connection devices.
In FIG. 1, 01 is a digital still camera device. Reference numeral 02 denotes a system control unit including a CPU, a NAND flash memory, an SDRAM, a timer, and the like, which are provided to control the entire digital still camera device 01.
Reference numeral 03 denotes an imaging unit including optical system parts (lens and lens driving motor) provided for imaging, a CCD, a CCD driving circuit, an A / D converter, and the like.

04 performs various image processing on the image signal obtained by the image pickup unit 03 and controls the CCD drive timing and lens drive motor of the image pickup unit 03 to switch the focal length and zoom position, perform focusing, exposure adjustment, and the like. The image processing unit includes an image processing DSP (digital signal processor), a RAM, and the like provided to perform compression and expansion of images.
05 performs signal processing for displaying the image signal processed by the image processing unit 04 on the LCD, generates various graphic images for the user interface, and displays them on the LCD 06 described below. This is a display control unit including a D / A converter, an on-screen display controller, and the like.

Reference numeral 06 denotes an LCD provided for displaying an image and displaying a graphic for a user interface. Reference numeral 07 denotes a recording medium interface unit including a memory card controller or the like provided for an interface with the recording medium.
Reference numeral 08 denotes a recording medium that is detachable from the digital still camera device 01 and includes a flash memory or the like provided to store a compressed image signal and various information related to the image.

09 is a user interface (not shown) such as a key and a dial (for example, a power switch, a release SW for release, a shooting mode dial for setting a shooting mode, a menu SW for various settings, and a blur described later. Provided to temporarily cancel the amount control, switch the presence / absence of the shooting mode using the blur amount control, and / or the blur control temporary release button), and perform the main power control to the main CPU (not shown) , A hard key interface unit including a sub CPU and the like.
Reference numeral 10 denotes a communication interface unit including a communication controller, which is provided to connect the USB and perform data communication. Reference numeral 11 denotes a PC (personal computer) for connecting the digital still camera device 01 via USB, transferring an image from the digital still camera device 01 for reproduction, and making various settings for the digital still camera device 01.

<Overview of operation>
First, the “conventional startup operation” will be described.
When the user turns on the power switch (not shown), the hard key interface unit 09 turns on the power supply to the main CPU. The main CPU in the system control unit 02 first starts access (program execution) from the boot unit of the NAND flash memory, and transfers program data to the SDRAM by the boot program. When the transfer to the SDRAM is completed, the program execution pointer (program counter) is moved to the transferred program on the SDRAM, and thereafter, the startup process is started by the program on the SDRAM.

The start-up process includes an OS (operating system) initialization, a lens barrel extension process, a recording medium initialization process, and the like. The lens barrel feeding process is performed by giving a pulse signal to the lens driving motor of the imaging unit 03 at predetermined intervals via the image processing unit 04.
Also, in the initialization process of the recording medium, after supplying power and a clock to the recording medium 08 via the recording medium interface unit 07, an initialization command is issued to the recording medium 08. The actual initialization process is performed in the recording medium 08, and the system control unit 02 checks the status of the recording medium 08 at a predetermined interval in order to detect the completion.

Next, “operation during photographing” will be described.
Prior to shooting, the user operates various keys SW and dial SW (not shown) to determine the shooting mode (normal mode, blur amount control mode, etc. described later). The user's operation content is determined by the system control unit 02 through the hard key interface unit 09, and the system control unit 02 generates a guidance graphic to the display control unit 05 according to the operation, and prompts the user to perform the next operation. When the photographing mode is determined, the system control unit 02 sets processing parameters corresponding to the mode in the image processing unit 04.

  Further, the user operates a zoom lever SW (not shown) to determine the angle of view (shooting range). The user's operation content is determined by the system control unit 02 through the hard key interface unit 09, and the system control unit 02 controls the imaging unit 03 in accordance with the operation to drive the lens. In accordance with control from the image processing unit 04, the imaging unit 03 performs an imaging operation for displaying a monitoring image (a through image obtained by capturing the subject image with the imaging unit and processing it according to the resolution of the display unit) prior to actual shooting. To start.

  The imaged data is continuously sent to the image processing unit 04. The image processing unit 04 performs processing such as color space conversion, gamma correction, and white balance adjustment, and then sends the image data to the display control unit 05. In the display control unit 05, the image data is signal-processed and displayed on the LCD 06, and the imaging state is presented to the user. When a release button (not shown) is pressed, the operation is discriminated by the system control unit 02 through the hard key interface unit 09 as in the mode setting.

  The imaging unit 03 performs focus adjustment according to the control from the image processing unit 04 and then sends the captured image to the image processing unit 04. The image processing unit 04 performs image processing and compression processing according to the shooting mode. The system control unit 02 reads the compressed image data, adds header information, and then writes the compressed image data to the recording medium 08 through the recording medium interface unit 07. This completes a series of shooting operations.

<Detailed operation>
Next, a description will be given of “an example of changing the blurring amount of the background portion in accordance with the user's operation”, which is a main part of the first embodiment.
The operation flow is shown in FIG. This flow shows the operation related to the operation during monitoring. When the monitoring operation is started, the system control unit 02 sets a blurring amount parameter described later to an initial value (= 5) (step 01-001). The system control unit 02 controls the image processing unit 04 and the imaging unit 03 to perform a CCDAF (CCD autofocus) scanning operation (step 01-002). Subsequently, the system control unit 02 determines a distance for each small region of each image or a parameter related to the distance (step 01-003).

  Hereinafter, a description will be given with reference to FIGS. In FIG. 2A, 100 indicates the angle of view of the monitoring image, and 101 indicates one AF evaluation value area. As shown in the figure, the AF evaluation value area is a small area that is equally divided within the angle of view, and the AF evaluation value (integrated value of the contrast of the image in the area) for each small area is obtained by CCDAF. The system control unit 02 analyzes the AF evaluation value for each lens position obtained by CCDAF scanning for each small area based on a predetermined algorithm, and determines the lens driving position corresponding to the peak position of the AF evaluation value. To do. Further, the system control unit 02 converts the driving position of the lens from the current zoom position into distance information for each small area.

  Here, the AF evaluation value is obtained by performing a horizontal HPF (high pass filter) operation on each pixel in the area and adding the obtained results. For example, a value such as ki = {− 1, −2,6, −2, −1} is used as the HPF coefficient. k0 is a coefficient that is multiplied by the pixel of the pixel in the horizontal direction-2 of the target pixel, k1 is a coefficient that is multiplied by the pixel of the pixel of interest in the horizontal direction-1 coordinate, k3 is a coefficient that is multiplied by the target pixel, and k4 is A coefficient to be multiplied by a pixel having a coordinate in the horizontal direction + 1 of the target pixel, and k5 is a coefficient to be multiplied by a pixel having a coordinate in the horizontal direction + 2 of the target pixel.

In order to obtain distance information from the AF evaluation value, a = bf / (b−f) is obtained from the Gaussian imaging equation, 1 / a + 1 / b = 1 / f. Here, a is the distance from the lens to the subject, b is the distance between the lens and the image sensor, and f is the focal length of the lens. The distance information from the lens to the subject is the distance information to be obtained. The focal length f of the lens is uniquely obtained from the zoom position at the time of shooting. The distance b between the lens and the image sensor is uniquely obtained from the driving position of the focus lens where the peak of the AF evaluation value is obtained.
As described above, it is possible to obtain distance information for each AF evaluation value area 101 of the entire region within the angle of view 100. If distance information of the entire area cannot be obtained, it is possible to perform interpolation processing on peripheral data, or change the filter at the time of AF evaluation value acquisition and perform rescanning.

  In FIG. 2A, reference numeral 102 denotes an AF area set as an area to be focused by AF. The system control unit 02 determines the area closest to the AF evaluation value area in the center of the screen as the AF area (step 01-004), and further determines the block equidistant from the AF area as the main subject block. (Step 01-005). In FIG. 2B, reference numeral 103 denotes a main subject block. The main subject block 103 includes an AF area 102.

  At this time, the system control unit 02 calculates and stores the average luminance of the image data at the position corresponding to the main subject block 103 (step 01-006). Further, the system control unit 02 determines the main subject area based on the obtained information on the main subject block 103 and the captured image (step 01-007). In this process, a region having an arbitrary shape including the main subject block 103 is determined by conventional image processing (contour extraction).

  In FIG. 2C, reference numeral 104 denotes a main subject area. The image processing unit 04 sequentially performs main subject image extraction processing, background image blurring processing, and composition processing based on the information of the main subject region 104 (steps 01-008 to 010). In FIG. 2D, 105 is a captured image, 106 is a main subject, 107 is an extracted main subject image, 108 is a background image, 109 is a blurred background image, and 110 is a composite image.

  In the main subject extraction process (step 01-008), the main subject is extracted by separating the image along the main subject region 104. As a result, the captured image 105 is separated into the main subject image 107 and the background image 108. In the background image blurring process (step 01-009), the background image 108 is blurred based on the blurring amount parameter to generate a blurred background image 109.

  Here, details of the blurring process (step 01-009) will be described based on the flow in FIG. The system control device 02 determines the processing contents as shown in Table 1 based on the blurring amount parameter (step 03-001).

In Table 1, the blurring amount is the value of the blurring amount parameter that determines the size of the blur, the reduction processing is the reduction rate of the reduction processing determined by the value of the blurring amount parameter, and the filter type is the type A or type B of the spatial filter described later. Is shown. The blur amount parameter is an integer value that changes in the range of 2 to 112.
Note that the denominator value 16 of the reduction ratio of the reduction processing is set to a value that is a common divisor of the horizontal size and vertical size of the image, and the image size after reduction has a fraction that is less than an integer in both the horizontal and vertical directions. Does not occur.

  If the value of the blur amount parameter is equal to or smaller than the predetermined value, only the spatial filter processing is performed without performing the reduction processing (steps 03-002, 003). Spatial filter processing is executed by the image processing unit 04 based on settings from the system control unit 02. In the spatial filter processing, the filter coefficient (k (ix, iy)) is calculated for the input image (In (x, y)) as shown in the following formula to obtain the output image (Out (x, y)).

An example of the filter coefficient is shown in FIG. FIG. 3A shows filter coefficients when the value of the blurring amount parameter is 2, and generates a blurred image in which the number of pixels having a diameter of the blur is equivalent to two.
In the figure, a circle indicated by a broken line indicates the size of the blur. Similarly, FIG. 3B shows the filter coefficient when the value of the blur amount parameter is 7. As described above, the system control unit 02 performs the blurring process by setting the filter coefficient so that the number of pixels having the diameter of the blur is equal to the value of the blurring amount parameter.

If the amount of blurring is greater than or equal to the predetermined amount, the image is once reduced, then the spatial filter is processed, and further enlargement is performed (steps 03-004 to 006). In the enlargement process, the enlargement process for the reciprocal of the reduction ratio performed in step 03-004 is performed, and as a result, the image size becomes the original size.
These reduction, spatial filter, and enlargement processes are executed by the image processing unit 04 based on settings from the system control unit 02. A blurring filter with a reduction process performs a blurring process by setting a filter coefficient such that the number of pixels having the diameter of the blur is equal to the value of (bluring amount parameter value) × (reduction rate). .
FIG. 3C shows the filter coefficient when the value of the blurring amount parameter is 28, and the number of pixels having a diameter of blur is (28) × (4/16) = 7.

Here, filter types A and B will be described. 3A, 3B, and 3C described so far are classified into filter type A, and FIG. 3D is classified into filter type B. FIG. 3D shows the filter coefficient when the value of the blurring amount parameter is 56, and the number of pixels having the diameter of the blur is (56) × (2/16) = 7. This is equal to the filter coefficient when the value of the blur amount parameter is 28.
However, in the coefficient of FIG. 3 (D), the coefficient of the donut-shaped portion surrounded by the double circles indicated by the wavy line is set to a large value, thereby reducing the visibility of the blur shape due to the reduction. It is preventing.

Hereinafter, the description will return to the flow of FIG. In the synthesis process (step 01-010), the main subject image 107 is superimposed on the blurred background image 109 to perform synthesis, and a synthesized image 110 is generated. The generated composite image is displayed on the LCD 06 via the display control unit 05 (step 01-011). This completes the processing of one frame of the monitoring image.
At this time, the system control unit 02 calculates the average luminance of the image data at the position corresponding to the main subject block 103 (step 01-012), compares it with the value calculated and stored in step 01-006, and compares the difference by a predetermined amount or more. If there is, the process proceeds to the CCDAF scanning operation again (step 01-013).

Further, when an operation for changing the blur amount is performed, the blur amount parameter is changed according to the operation (step 01-014, 015), and the above operation is repeatedly executed until the monitoring is completed (step 01-016).
The monitoring image processing for each frame is repeatedly performed from step 01-007. When the release button is pressed, the same blurring process as in steps 01-007 to 010 is performed on the captured image, and an image with a blurred background is recorded. In this case, (blurring amount parameter at the time of monitoring) × (recording image size) / (monitoring image size) is applied as the blurring amount parameter.

Next, a procedure for changing the blur amount when the focal length or zoom position of the zoom lens is changed will be described. The operation flow is shown in FIG. Steps 02-001 to 008 are the same as steps 01 to 001 to 008. Prior to entering step 02-010, the control unit acquires information on the current focal length position and stores it in the memory.
(Normally, this is performed when the zoom position is changed by the zoom lever, but may be reacquired at this point).

The image processing unit 04 performs a background image blurring process with a blurring amount corresponding to the zoom position (focal length) (step 02-010). The internal processing in step 02-010 is shown in the operation flow of FIG.
Here, the correspondence of the parameter of the blur amount corresponding to the zoom position is determined by appropriately making a table or the like. In the present invention, the zoom position changes as wide (wide-angle end), wide mean (between wide-angle end and intermediate position), mean (intermediate position), mean tele (middle between the intermediate position and telephoto end), tele (telephoto end). In this case, the blur amount in Table 1 is sequentially switched to five stages.
Further, a configuration is also possible in which the reverse (configuration in which the blurring amount is reduced as the focal length becomes longer) is possible in accordance with the shooting mode dial or the presetting by menu setting . In the case of this, not be a silver halide camera, becomes a configuration in which the blur amount closer to the wide-angle increases, while unnatural of digital camera unique it is also possible to carry out a wide photographic expression.

In addition, if the blur control temporary release key is pressed during monitoring, the process of step 02-010 is skipped (see FIG. 5), and blur control can be easily added based on the confirmation result in monitoring. It can be set as the structure which can be cancelled | released.
In addition, when the blur control temporary release key is pressed and the release key is pressed as it is, it is possible to take a picture in the state where the blur control is not performed by attracting the processing of the monitoring process state. Even if it is a mode that performs blur control shooting, if the user decides that it is better not to perform blur control by simply checking the blur state (existing or not) during monitoring, do not perform blur control It is possible to perform shooting in a state.

  In the compositing process (step 02-011), the blurred background image 205 is superimposed on the blurred background image 205, and the main subject image 202 is further superimposed to generate a composite image 207. Steps 02-012 to 014 are the same as steps 01-011 to 013.

<< Second Embodiment >>
In the present description, only the part in which the first embodiment is changed (step 02-010) will be described.
The image processing unit 04 performs a blurring process on the background image with a blurring amount corresponding to the presence / absence of use of the digital zoom and the enlargement magnification (pseudo focal length) of the digital zoom (step 02-010). Here, the correspondence of the parameters of the blur amount corresponding to the presence / absence of use of the digital zoom and the enlargement magnification (pseudo focal length) of the digital zoom is determined as appropriate, for example, as a table.

For example, when the lens (not shown) in FIG. 1 has a digital zoom function as a single focus lens, it is determined whether or not the digital zoom is used in step 02-010 processing, and if not used, the blur control is not performed. Step 02-010 is exited. When digital zoom is used, the blurring amount in Table 1 is sequentially switched in five steps as shown in the operation flow of FIG. 5 according to the enlargement magnification.
Depending on the shooting mode dial or menu settings, the reverse setting (decreasing the blur amount according to the magnification) (setting example shown in Table 2 in FIG. 6) may be possible. Good . For this, as magnification increases, it becomes a configuration in which blurring amount is small, unnatural while it is also possible to perform a wide photographic representation width.

<< Third Embodiment >>
In this description, only the parts added / changed to the first and second embodiments will be described.
In order to obtain a more natural blur, the distance of the main subject based on the AF evaluation value acquired in advance in the flowchart of FIG. 4A is combined with the present embodiment, the focal length position in the first embodiment, The blur amount may be changed using the distance to the subject as a parameter.
In this case, it goes without saying that the longer the focal length and the closer to the main subject, the more natural the image will be when the blur amount is increased. Further, in this case, it becomes more effective if the five-step parameters in Table 1 are combined and processed in more detailed steps as shown in Table 2 (see FIG. 6).

  Similarly, as shown in Table 2 (see FIG. 6), when the main subject and the foreground and the background can be separated and the respective distances can be grasped, a natural blur amount is set in accordance with the gist of the present invention. Control the blur amount according to the distance relationship between the forescape, the main subject, and the background so that it matches the depth-of-field calculation of the optical lens (i.e., when the foreground blur amount is the same distance relationship, It is possible to blur the image so that it is larger than the amount). Conversely, the control method is such that only the foreground is blurred and the main subject and the background are not blurred, and the blur amount of the foreground is set smaller than the background. Is possible.

  As described above, according to the present invention, the telephoto effect of a zoom lens can be emphasized with a simple configuration, and a photographic expression with a blurring effect that cannot be realized with a silver halide camera can be easily performed. Thus, it is possible to perform shooting by simply selecting whether or not to add blur control. Further, in the present specification, the method for separating the main subject and other regions, the distance information acquisition method, the blurring process, and the subsequent synthesis method are only described as one embodiment. Other methods may be used without departing from the scope of the present invention.

It is a block diagram which shows the structure of embodiment of this invention. It is a figure which shows the image processing of the 1st embodiment. It is a figure which shows distribution of the filter coefficient of the 1st embodiment. It is an operation | movement flowchart of each embodiment of this invention. 5 is an operation flowchart illustrating an example of internal processing of step-02-010 in FIG. It is the figure which represented the 5 step | paragraph parameter as Table 2 in the said 2nd Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 01 ... Digital still camera apparatus 02 ... System control part 03 ... Imaging part 04 ... Image processing part 05 ... Display control part 06 ... LCD
07 ... Recording media interface unit 08 ... Recording media 09 ... Hard key interface unit 10 ... Communication interface unit 11 ... PC

Claims (6)

A zoom lens with variable focal length,
Zoom lens control means for controlling the focal length of the zoom lens;
Subject image separation means for separating the main subject portion area of the subject image captured through the zoom lens and the zoom lens control means and the region other than the main subject portion;
A blur amount control unit capable of blurring a region other than the main subject portion separated by the subject image separation unit and changing a blur amount;
If you change the focal length or the zoom lens position of the zoom lens, have a, a blurring amount changing means for changing the amount of blur that is an output from the blurring amount control means,
The image blurring apparatus according to claim 1, wherein the blur amount changing unit controls the blur amount to be decreased as the focal length of the zoom lens increases or the zoom lens position approaches the telephoto position . An imaging lens;
A digital zoom processing means for obtaining an image as if the focal length was changed in a pseudo manner by electrically processing a subject image captured by the imaging lens;
Subject image separation means for separating a main subject portion area of a subject image captured through the imaging lens and the digital zoom processing means and a region other than the main subject portion;
A blur amount control unit capable of blurring a region other than the main subject portion separated by the subject image separation unit and changing a blur amount;
If you change the magnification or pseudo focal length of the digital zoom by the digital zoom processing unit, have a, a blurring amount changing means for changing the amount of blur that is an output from the blurring amount control means,
The imaging apparatus according to claim 1, wherein the blur amount changing unit controls the blur amount to be decreased in accordance with an increase in an enlargement magnification of the digital zoom by the digital zoom processing unit or an increase in a pseudo focal length . The subject image separation means separates the main subject portion area and the main subject portion area into a foreground region and a background region,
The imaging apparatus according to claim 1, wherein the blur amount control unit performs control so as to blur only the foreground region of the region other than the main subject portion. The subject image separation means separates the main subject portion area and the main subject portion area into a foreground region and a background region,
The imaging apparatus according to claim 1, wherein the blur amount changing unit controls the blur amount of the foreground area to be smaller than that of the background area. Furthermore, a shooting mode setting means for setting various shooting modes, and a display means for displaying the subject image,
In the shooting mode setting for performing blur control by the blur amount control means, it has blur control temporary release means that can temporarily add and release blur control when checking the blur processing status before shooting. The imaging device according to claim 1 or 2. The imaging apparatus according to claim 5, further comprising a unit that performs shooting without performing blur processing by performing shooting while the blur control temporary release unit is operated.