JP2002044514A - Electronic camera - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic camera that executes preliminary photographing to properly segment an object image depending on a difference from an influence rate of an irradiation light in optimum timing. SOLUTION: A strobe emission image (a) and a strobe non-emission image (b) are acquired by preliminary photographing executed before main photographing when automatically segmenting an object image into a major area and a background area depending on a difference from an influencing rate of the emitting light in order to execute automatic adjustment for photographing conditions while surely targeting the major area. On the other hand, the preliminary photographing executed after the main photographing acquires the strobe emission image (a) and the strobe non-emission image (b) for conduction of similar segmentation in order to simplify the image processing to apply different processing to the major area and the background area without the need for skill or considerable effort.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention
The present invention relates to an electronic camera that captures an image of a subject using a semiconductor imaging device such as a two-dimensional image sensor, and in particular, performs preliminary photographing for separating the subject image into, for example, a main region and a background region based on a difference in the influence rate of irradiation light. The present invention relates to an electronic camera considering timing and the like.

[0002]

2. Description of the Related Art In recent years, a subject image is formed on a solid-state image sensor, for example, a CCD two-dimensional image sensor by an image pickup optical system and converted into an electric signal. A so-called electronic camera that records data on a recording medium such as a disk has been widely used.

An electronic camera of this type has a function of performing preliminary photographing as preparation for actual photographing and automatically adjusting photographing conditions based on image data of a subject image obtained in the preliminary photographing. There are many. Therefore, the user does not need much skill, and can perform shooting under appropriate shooting conditions according to the situation at that time.

[0004] Further, since the subject image photographed by the electronic camera is recorded as digital data called image data or the like, it is taken into a personal computer, and is divided into a near view and a distant view, that is, a main area and a background area. Various image editing can be freely performed, for example, by performing different processing for the area or cutting out only the main area.

However, conventionally, the automatic adjustment of the photographing conditions by the preliminary photographing is often performed by sampling image data corresponding to a predetermined fixed position such as the center of a subject image. In some cases, there is a possibility that the adjustment is performed targeting the background area instead of the main area. More specifically, for example, not only a subject having a composition in which a person is arranged at one corner of the scenery, but also a composition in which two persons are arranged in the center, the central portion to be sampled is placed between the two persons. There is a problem in that the adjustment is not performed as desired for a subject that does not look right.

[0008] Even though various image editing operations can be freely performed, it is necessary to have a considerable skill and a great deal of labor to clearly separate the subject image into a main area and a background area. Therefore, although it has been answered to some extent, there has been a problem that it is not very convenient for general users.

Further, for example, Japanese Patent Application Laid-Open No. 11-29890
In a night view sync mode in which a subject with a night view as a background is flashed as in the digital camera image processing method described in Japanese Patent Application Laid-Open No. 8-208, the background portion to which flash light does not reach falls below the black level as image data. Attempts have been made to optimize the focus and white balance in both the main part and the background part using this method. However, this method can be used only when the background is a night view, Since the level is used as a criterion, there is an inherent defect that, for example, when a main part such as a person wearing black clothes contains black, that part is also determined to be a background part.

In view of the above, for example, attention is paid to the difference in the influence of the irradiation light from a strobe or the like on each area of the subject image, and the change in brightness between when the light is emitted and when the light is not emitted is captured. Separation into the main part area and the distant view (background part area) makes it possible to execute the automatic adjustment of the photographing conditions without fail while targeting the main part area, and also requires skill and considerable labor. Without needing
Attempts have been made to make it possible to easily perform image processing such as performing different processing in the main part region and the background part region.

[0009]

When the subject image is divided into, for example, a main part region and a background part region from the difference in the influence rate of the irradiation light, what is the purpose of the division and the purpose of the purpose? It is desirable to determine the execution timing of the preliminary photographing including the emission of the strobe light according to. However, in the prior art, little consideration has been given to the execution timing of the preliminary photographing including the emission of the strobe light.

The present invention has been made in view of the above circumstances, and the timing of execution of preliminary photographing for appropriately dividing a subject image into, for example, a main area and a background area from the difference in the influence rate of irradiation light. It is an object of the present invention to provide an electronic camera in consideration of the above.

[0011]

In order to achieve the above-mentioned object, the electronic camera according to the first aspect of the present invention firstly performs a first preliminary photographing with a strobe light emission, and then performs a strobe light emission. A second preliminary photographing without accompanying is executed, and the subject is divided into a main part region and a background part region based on the luminance change between the two subject images obtained in the two preliminary photographings. The main shooting is executed after the setting of the target imaging condition is executed.

Further, the electronic camera according to the second aspect of the present invention
Perform the first preliminary shooting without flash emission,
Next, a second preliminary photographing with flash emission is performed, and the subject is divided into a main region and a background region based on a change in luminance between the two subject images obtained in the second preliminary photographing. The main imaging is performed after the setting of the imaging conditions for the cut main part region is performed.

In the electronic camera according to the first and second aspects of the present invention, the automatic adjustment of the photographing conditions can be performed while reliably targeting the main area.
When automatically dividing a subject image into a main part region and a background part region from a difference in the influence rate of irradiation light, preliminary photographing including flash emission is executed at an optimal timing.

An electronic camera according to a third aspect of the present invention comprises:
The main photographing is performed, and thereafter, the first preliminary photographing with strobe light emission is performed, and then the second preliminary photographing without strobe light emission is performed. The subject image is divided into a main part region and a background part region from the luminance change between the two subject images, and different image processing or encoding processing is performed on the divided main part region and the background part region. is there.

The electronic camera according to the fourth aspect of the present invention comprises:
The main photographing is performed, and then, the first preliminary photographing without flash emission is performed, and then the second preliminary photographing with flash emission is performed. The subject image is divided into a main part region and a background part region from the luminance change between the two subject images, and different image processing or encoding processing is performed on the divided main part region and the background part region. is there.

The electronic camera according to a fifth aspect of the present invention first comprises:
The main photographing is performed, and thereafter, the preliminary photographing with flash emission is performed only once, and the subject image is changed to the main part region from the luminance change between the two subject images obtained in the main photographing and the preliminary photographing. And a background area, and different image processing or encoding processing is performed on the separated main area and background area.

In the electronic camera according to the third to fifth aspects of the present invention, image processing such as performing different processing in the main part region and the background part region can be easily performed without requiring skill or considerable labor. In order to make it possible, when the subject image is automatically divided into the main area and the background area based on the difference in the influence rate of the irradiation light, the moment when the user captures a photo opportunity and the time when the actual shooting is performed Preliminary photographing including flash light emission is executed at an optimal timing without causing a time lag between the two.

Further, the electronic camera according to the sixth aspect of the present invention can be obtained by performing a plurality of first preliminary photographing operations with a strobe light emission and a second preliminary photographing operation without a strobe light emission so that the light emission amounts are different from each other. The subject image is divided into a plurality of regions based on the luminance change between at least three or more subject images.

In the electronic camera according to the sixth aspect,
In order to be able to control the automatic adjustment of the shooting conditions in more detail, or to be able to easily perform image processing such as performing different processing on two or more areas,
When the subject image is divided into multiple stages by multi-stage light emission, preliminary photographing including strobe light emission is executed at an optimal timing.

[0020]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an external view of an electronic camera according to an embodiment of the present invention.

As shown in FIG. 1, this electronic camera mainly comprises a camera body 1 and a lens barrel 2.
The camera body 1 has an electronic viewfinder (EVF) 3
In addition to and flash 4, release button 5 as an operation unit,
A mode dial 6 and a cross key 7 are provided, and a color liquid crystal display (LCD) 8 is provided as a display unit.

Next, a detailed configuration of the inside of the electronic camera according to this embodiment will be described with reference to FIG.

In FIG. 2, after the subject light has passed through a zoom lens 9 and an AF (automatic focusing) lens 10 provided in the lens barrel 2, the amount of light is controlled by a diaphragm 11. The zoom lens 9 includes the optical zoom unit 12 and the AF lens 1.
Numeral 0 is driven by an AF mechanism 13, and subject light having passed through the zoom lens 9, the AF lens 10 and the aperture 11 is guided into the camera body 1, and a shutter 14 is provided.
Is opened, the light enters a CCD two-dimensional color image sensor (hereinafter simply referred to as a CCD) 15 which is a color solid-state imaging device. As a result, a subject image is formed on the imaging surface of the CCD 15.

The CCD 15 constitutes an imaging surface by arranging a plurality of pixels for performing photoelectric conversion in a two-dimensional matrix.
Furthermore, a color filter is arranged on the imaging surface,
The signal charges corresponding to the subject image formed on the imaging surface are accumulated. The CCD 15 is provided with an imaging circuit 16, which controls exposure, reading, element shutter, gain adjustment, power supply, and the like. The output from the CCD 15 is converted into a digital signal by an A / D converter 17 and then guided to an image processing unit 18 where ISO sensitivity setting, auto white balance, luminance /
By performing color signal generation, gamma processing, and the like, a color image signal in a predetermined format is generated. The image processing unit 18 also executes a zoom ratio control in a resizing process or the like based on a control signal supplied from the electronic zoom unit 19.

The color image signal generated by the image processing section 18 is temporarily stored in a buffer memory 20 composed of, for example, a DRAM. This buffer memory 2
The liquid crystal control unit 21 is connected to 0, and the color image signal is
Here, after being converted into a form suitable for display output, it is supplied to a color liquid crystal display (LCD) 8 such as a TFT system and displayed as an image.

The buffer memory 20 is further connected to a compression / expansion unit 22. The compression / expansion unit 22 reads out the image signal stored in the buffer memory 20 and performs a compression (encoding) process, thereby forming a form suitable for recording on the recording medium 23. An expansion processing section for reading out image data recorded on the medium 23 and performing expansion (decoding) processing. As a method of this compression processing, for example, a JPEG method is used, but it is not limited to this. At the time of reproduction, the expanded image signal is temporarily stored in the buffer memory 20,
Color liquid crystal display (LC) via liquid crystal controller 21
D) Displayed as appropriate at 8. As the recording medium 23, for example, a memory card constituted by a semiconductor memory such as a card type flash memory is generally used.
The present invention is not limited to this, and various forms such as a magnetic recording medium such as a hard disk and a floppy (registered trademark) disk can be used.

This electronic camera is provided with a peeping type electronic viewfinder (EVF) 3 separately from a color liquid crystal display (LCD) 8, and controls an output from an A / D converter 17. , Finder image generator 2
In step 4, a moving image process of n frames / sec is performed and displayed as a through image from the electronic viewfinder (EVF) 3 via the liquid crystal control unit 25 or from the color liquid crystal display (LCD) 8 via the liquid crystal control unit 21. Is done.

The strobe 4 is a light source for photographing a dark subject, and the amount of light emitted from the light emitting section 27 is controlled by a strobe control circuit 26. Strobe control circuit 26
Is provided with a strobe capacitor capable of storing a predetermined amount of electric charge, and drives the light emitting unit 27 by charging and discharging the strobe capacitor. Further, the illumination angle is controlled by driving the flash cover 29 by the motor 28.

The above operations are all controlled by the system controller 30, and the system controller 30 transmits the release button 5
The above-described operation control is executed in accordance with the contents of various operations such as pressing of the button.

The system controller 30 includes a photographing control unit 32, an image segmentation control unit 33, and an AF control unit 3.
4. An AE control unit 35, a zoom control unit 36, and a strobe control unit 37 are provided.

The photographing control section 32 controls each section of the camera based on the set photographing conditions, and provides necessary image processing parameters and the like. Note that the photographing conditions here include so-called exposure and shutter speed, whether or not strobe light is emitted,
This includes not only shooting conditions in a narrow sense common to silver halide cameras, such as light emission amount correction, but also image processing conditions such as white balance, color processing (color table), and gamma.

The image segmentation control unit 33 performs preliminary photographing, which is a preparation for the actual photographing, twice when the strobe 4 emits light and when the strobe 4 does not emit light. This is for realizing a control unique to the present invention, such as appropriately dividing the region into the background region and effectively supporting setting of photographing conditions and image processing by this division. This point will be described later. I do.

The AF controller 34 controls the A / D output of the CCD 15 based on the A / D output of the CCD 15 and the photographing conditions by the contrast AF method.
The F mechanism 13 is controlled. In addition, the AE control unit 35
The drive of the aperture 11 and the shutter 14 is controlled based on the A / D output of D15 and the photographing conditions. Zoom control unit 36
Controls the optical zoom unit 12 based on the A / D output of the CCD 15 and shooting conditions. And the strobe control unit 3
7 is based on the A / D output of the CCD 15 and shooting conditions,
A signal for controlling the presence / absence of light emission and the amount of light emission is provided to the strobe control circuit 26 and the motor 28 is controlled.

Here, the preliminary photographing, which is realized by the image segmentation control unit 33 and is a preparation for the actual photographing, is performed by the strobe 4.
It is performed twice when the light is emitted and when the light is not emitted, and the subject image is appropriately divided into, for example, a main part area and a background part area by a change in luminance between the two. The control unique to the present invention, such as effectively supporting the control, will be described in detail.

For this control, the electronic camera is further provided with an image dividing unit 38 that is driven and controlled by the image dividing control unit 33.
Includes a separation information holding unit 39, a luminance change detection unit 40, and a separation processing unit 41.

The separation information holding unit 39 stores the A / A of the CCD 15 obtained by the preliminary photographing with the emission of the strobe 4.
A / D of the CCD 15 obtained by preliminary photographing without the emission of the flash 4 and the image a at the time of the flash emission as the D output.
In addition to holding the flash output non-emission image b which is the D output, it also holds the separation information c generated through the luminance change detection unit 40 and the separation processing unit 41 based on these.

The luminance change detecting section 40 obtains a difference in luminance for each image data between the image a when the strobe light is emitted and the image b when the strobe light is not emitted, and transfers the result to the separation processing section 41.

Then, the division processing unit 41 divides the subject image into, for example, a main part and a background part from the information received from the luminance change detection unit 40, and stores the division result in the division information holding unit 39 as division information c. .

By providing the image segmenting section 38, the electronic camera can appropriately segment the subject image as shown in FIG. 3, for example, into a main area a1 and a background area a2 as shown in FIG. In other words, the setting makes it possible to effectively support setting of photographing conditions, image processing, and the like. The setting of the photographing conditions and support for image processing will be described later.

Next, with reference to FIG. 5 to FIG. 20, the principle of operation of the electronic camera regarding the separating function will be described.

This electronic camera has roughly two operation modes, a photographing mode and a reproduction mode.
As the photographing modes, there are a plurality of various photographing modes including a dividing photographing mode for operating the above-described dividing function. The operation mode is set by operating the mode dial 6.
When the cut-off shooting mode is set by the operation described above, the above-described cut-out processing is executed. Further, setting of various photographing conditions such as exposure and shutter speed is performed by selecting a menu item using the cross key 7.

Therefore, a user who wishes to operate the separation function first operates the mode dial 6 to set the operation mode to the separation photographing mode (FIG. 5).
In step A1), the user operates the cross key 7 to set other shooting conditions (step A2 in FIG. 5).

As described above, by providing the electronic camera with the division photographing mode as one operation mode, the above-described division function can be operated according to the user's request. Conversely, useless operation is not generated for an undesired user, so that the battery life is not deteriorated.

After completing this setting, the user presses the release button 5 to perform actual shooting.
In this divided shooting mode, prior to the actual shooting,
Preliminary photography is performed. FIG. 6 is a flowchart showing an operation procedure at the time of the preliminary photographing.

At the time of preliminary photographing, the photographing control unit 28 first executes the first photographing process while instructing the strobe control unit 31 to emit light from the strobe 4 (step B1 in FIG. 6) (FIG. 6).
Step B2), on the other hand, the image segmentation control unit 29
The A / D output (image a at the time of flash emission) of the CCD 15 obtained by this photographing process is stored in the separation information holding unit 33 (step B3 in FIG. 6).

Subsequently, the photographing control unit 28 executes the second photographing process (step B5 in FIG. 6) without instructing the strobe control unit 31 to emit the strobe light 4 (step B4 in FIG. 6). Then, the image segmentation control unit 29 stores the A / D output of the CCD 15 (the image b when the strobe light is not emitted) obtained by the photographing process in the segmentation information holding unit 33 (step B6 in FIG. 6).

Next, the image segmentation control unit 29 causes the luminance change detection unit 34 to compare the image a with strobe light emission and the image b with no strobe light held in the segmentation information holding unit 33 to obtain the luminance. The change is detected (step B7 in FIG. 6), and the separation processing unit 35 is caused to separate the subject image into, for example, a main part and a background part from the detected luminance change (step B8 in FIG. 6). At this time, the division processing unit 35 records the division result (division information c) in the division information holding unit 33 (FIG. 6).
Step B9).

The light that the strobe 4 reaches the subject decreases in proportion to the square of the subject distance. Therefore, the amount of reflected light from the subject incident on the camera becomes larger as the subject is closer, and becomes smaller as the subject is farther away. For example, when the sampling positions of the subject image shown in FIG. 3 are arranged as shown in FIG. 7A, the luminance value of the image a with strobe light emission and the luminance value of the image b with no strobe light emission are shown in FIG. 7 (b), and as a result, FIG.
Difference data is calculated as shown in FIG. And
The distance of the subject is detected based on the calculated difference data.

The division processing section 35 performs the division of the main part region and the background part region of the subject image based on, for example, the following algorithm.

(1) A portion where the luminance change occurs is defined as a main portion region, and a portion where the luminance change does not occur is defined as a background portion region.

(2) A portion where a change exceeding a predetermined threshold value occurs is defined as a main portion region, and other portions are defined as a background portion region. This threshold value may be fixedly given or may be arbitrarily set by the user by operating the cross key 7 or the like.

(3) A threshold value is obtained by a predetermined calculation from the maximum value and the minimum value (no change) of the luminance change, and a portion where a change exceeding the obtained threshold value occurs is defined as a main portion area. A part other than is defined as a background part area.

The segmentation information c may be any information as long as it can separate the subject image into a main area and a background area. For example, the information indicating the outline of the main area and which side of the outline is determined. What is necessary is just to hold | maintain the information which shows a main part area | region.

Steps B1 to B3 in FIG.
Acquisition of image a at the time of strobe emission and Steps B4 to B4 in FIG.
The order of obtaining the image b when no flash is fired in step B6 may be changed.

Further, since the subject image is divided into a main part area and a background part area by the difference data calculated from the luminance value of the image a with flash emission and the luminance value of the image b without flash light, the background must be a night scene. There is no limitation that must be applied, and the present invention can be applied to daytime shooting.

As a result, appropriate segmentation is automatically performed without requiring any skill or labor of the user as in the related art.

When the preliminary photographing is completed, the actual photographing is executed. FIG. 8 is a flowchart showing the operation procedure at the time of the main shooting.

At the time of actual photographing, the photographing control unit 28 first inputs the division information c stored in the division information holding unit 33 (step C1 in FIG. 8), and sets various photographing conditions based on the division information c. (Step C in FIG. 8)
2).

As the setting items of the photographing conditions based on the separation information c, for example, the following items can be considered.

(1) Automatic focus (AF) area: An AF area is set in a main part of a subject.

(2) Automatic exposure (AE) area: An AE area is set in the main part of the subject.

(3) Strobe irradiation angle: The irradiation angle is set according to the main part of the subject.

(4) Zoom ratio: The zoom ratio is set such that the main part of the subject is within a frame with a predetermined size.

As described above, by sampling image data corresponding to a predetermined fixed position such as the center of a subject image as in the related art, automatic adjustment of shooting conditions is performed not for the main part but for the background part. It is possible to prevent the adjustment from being performed.

Note that (1) to (3) are for ensuring that the target for adjustment matches the main part. For example, as shown in FIG. 9A, even if the composition is such that the AF area b may be placed in an inappropriate area in the related art, as shown in FIG. AF area b is placed at FIG.
As shown in FIG. 10A and FIG. 10B, the irradiation area c of the strobe 4 is automatically adjusted according to the position of the main part area in the subject image.

On the other hand, (4) controls the focal length so that the ratio between the main part and the background part is within a predetermined value in terms of composition. For example, as shown in FIG. The focal length is adjusted so that the image becomes a subject image as shown in FIG. This adjustment is performed by the optical zoom unit 12.
, And the electronic zoom control by the electronic zoom unit 19, or both. This function is effective when, for example, creating an entrance permit with a face photograph and taking a photograph of the face photograph with a predetermined ratio of space in the frame.

When the setting of the photographing conditions is completed, the photographing control section 28 executes a photographing process based on the photographing conditions (step C3 in FIG. 8), and then, based on the previously inputted cutting information c, Image processing is performed on the subject image obtained by this photographing processing (step C in FIG. 8).
4).

According to the segmentation information c, for example, the following image processing can be performed.

(1) Different sensitivity (ISO) processing is executed in the main part area and the background part area.

(2) Different sharpness processing is executed between the main part area and the background part area.

(3) Blur only the background area or change the color.

More specifically, for example, sensitivity processing is performed to increase the sensitivity of a main portion area of a subject image captured in a backlight situation, and sensitivity processing is performed to decrease the sensitivity of one background area. This makes it possible to make the main part region where the light is weak bright, and to darken the background part where the light is too strong. In addition, by performing a sharpness process with a higher degree of emphasis on the main portion region than the background portion region, it is possible to make the main portion region stand out more.

For example, the sensitivity is set to ISO only in the main area.
By performing different sensitivity processing between the main part area and the background part area, for example, by correcting twice from 100 to ISO 200 and leaving the background part area at ISO 100, the dark main part area a1 as shown in FIG. Thus, more effective image processing, such as correcting only the image brighter, can be executed.

It is preferable that these functions be further provided with an automatic mode and a manual mode in accordance with the operation of the cross key 7, for example. In the sensitivity processing in the automatic mode, a main portion area is extracted from the image stored in the buffer memory 20 after the main shooting, and the brightness is integrated to determine whether the brightness is appropriate. If it is not appropriate, the image processing unit 18 performs sensitivity correction only on the main area. If the reference is ISO100, ISO200, 400,...
And increase the sensitivity. Conversely, if it is too bright,
The sensitivity may be lowered to O50, 25. After the above processing is completed, this image is compressed and recorded on the recording medium 23.

On the other hand, the sensitivity processing in the manual mode is as follows.
This is possible even after being recorded on the recording medium 23,
The brightness of the reproduced image is set to a desired value by raising or lowering the ISO sensitivity while operating the cross key 7. At this time, the sensitivity correction of the main area is performed in the image processing unit 18 according to the setting, and the user can arbitrarily perform the brightness correction while actually viewing the corrected image. Then, after a series of operations is completed, an image in which the main part area has been corrected to the set ISO sensitivity is automatically recorded on the recording medium 23. Further, in this manual mode, the main area may be left as it is, and only the ISO sensitivity of the background area may be arbitrarily set.

The sharpness processing in the automatic mode is performed by the image processing section 18 in which the main area is automatically subjected to the high-enhancement sharpness processing, and the background area is automatically subjected to the low-enhancement sharpness processing. , An arbitrary degree of emphasis can be set for each of the main area and the background area.

Although the background can be blurred by this sharpness processing, it may be performed by, for example, cutting a high-frequency component of the spatial frequency of the luminance data with a low-pass filter, or by thinning out image data. The resizing process may be performed by performing a resizing process to reduce the image to an original size without performing interpolation. Further, the color is changed by replacing the image with image data of a predetermined color or pattern or a color or pattern prepared by the user. For example, taking the face photograph used for the above-mentioned admission permit as an example, the background can be easily replaced with a predetermined color, so that not only compositional considerations are unnecessary, but also the selection of shooting locations including the background can be made. Not required.

After the end of the image processing, the photographing control section 32 executes an image recording process based on the previously inputted division information c (step C5 in FIG. 8).

As the image recording process based on the separation information c, for example, the following is conceivable.

(1) The main area and the background area are recorded as separate files. In this case, for example, predetermined dummy data is supplemented in the background area of the file in which the main area is recorded. As the dummy data, data of a predetermined color may be used, or other predetermined identification data may be used. The association between the two files may be performed according to a naming rule, or may be stored as a pair in the same directory. Alternatively, link information for managing these associations may be separately stored. Further, in this case, it is preferable to record the segmentation information c as another file and perform the association.

(2) The main area and the background area are recorded as the same file, and the segmentation information c is recorded as another file. The association between the two files in this case is
Same as (1).

(3) The main area and the background area are recorded as the same file, and the division information c is stored as header information in the file.

When the main part area and the background part area are recorded as separate files, for example, the following can be further performed as an image recording process based on the separation information c.

(1) Encoding is performed at different compression rates in the main part area and the background part area.

(2) Encoding is performed at different pixel thinning rates in the main part area and the background part area.

(3) Encoding is performed with different bit widths in the main area and the background area.

That is, the main area can be encoded at a higher resolution than the background area, and image data can be more efficiently recorded on a recording medium having a finite capacity. For example, as shown in FIG. 13, when the high image quality mode (SHQ) is set, only the number of pixels in the background area is reduced from 1600 × 1200 to 1024 × 768, and Only compression ratio is 1
Increase from / 8 to 1/16. Similarly, when the standard image quality mode is set, only the number of pixels in the background area is set to one.
From 024 × 768 to 640 × 480, only the compression ratio of the background area is increased from ８ to 1/16.

By recording the main area and the background area as separate files, other electronic devices such as a personal computer and a printer can handle only the main area.

As described above, in this electronic camera, by focusing on the degree of influence of the subject image due to the emission of the strobe light 4, the subject image can be divided into, for example, a main part area and a background part area without adding special parts. Appropriately,
This division makes it possible to effectively support imaging processing, image processing, and the like.

Further, the separation information c obtained by the electronic camera is effective not only in the shooting mode but also in the reproduction mode.

For example, based on the separation information c,
Only the main area is cut out from the subject image and displayed (Fig. 1
(Step D1 of Step 4), and then combine and display the cut-out main part area and a separately prepared background image (Step D2 of FIG. 14). Then, the composited image is re-recorded on the recording medium 22 as desired by the user (step D3 in FIG. 14). For example, taking the above-described subject image in FIG. 3 as an example, it is possible to easily create an image as shown in FIG. 16 by synthesizing the main region and a background image as shown in FIG. Become.

As described above, various kinds of reproduction processing and processing can be performed by holding the division information c for appropriately dividing the subject image into, for example, a main part area and a background part area.

In the above-described embodiment, an example has been described in which the preliminary photographing is performed as preparations for the main photographing. This is because it is assumed that the segmentation information c is reflected in the photographing conditions. Considering that only the processing is used, the processing may be executed as post-processing of the main photographing. In this case, it is possible to perform preliminary photographing for obtaining the segmentation information c without causing a time lag between the moment when the user captures a photo opportunity and the actual photographing.

FIGS. 17 and 18 show variations of the sequence between the preliminary photographing and the main photographing and the sequence of the preliminary photographing.

As shown in FIG. 17, a variation of the sequence between the preliminary photographing and the main photographing is a first pattern (FIG. 17) in which the preliminary photographing is executed as a pre-process of the main photographing.
(A)) and a second pattern (FIG. 17 (b)) in which the preliminary photographing is executed as a post-process of the main photographing.

The first pattern is applied to a case in which a preparatory process including setting of photographing conditions is executed based on the segmentation information c obtained by the preliminary photographing, and then the actual photographing is executed.
The second pattern is applied when the segmentation information c obtained by preliminary photographing is used only for image processing.

On the other hand, as a variation of the sequence of the preliminary photographing, as shown in FIG. 18, the preliminary photographing (ST) with the emission of the strobe 4 is executed for the first time, and the preliminary photographing without the emission of the strobe 4 is performed for the second time. First to execute (non-ST)
(FIG. 18 (a)), a second preliminary photographing (ST) without flash 4 emission is performed, and a second preliminary photographing (ST) with flash 4 emission is performed. (FIG. 18 (b)) and a third pattern (FIG. 18 (c)) in which preliminary photographing (ST1, ST2, non-ST) involving emission of the strobe 4 is performed a plurality of times while changing the light amounts thereof. And the like.

The first and second patterns are mainly applied to the case where the subject image is divided into two regions of a main portion region and a background portion region, and the third pattern is formed by dividing the subject image into at least two or more regions. Applied when separating into regions. In this case, it is necessary to hold a plurality of images a at the time of strobe light emission, but by using these, it is possible to perform multi-stage area segmentation according to the distance. For example, it is possible to individually cut out each of the subjects d1 to d3 from a subject image as shown in FIG. 20 obtained by shooting in a situation as shown in FIG. 19, whereby the automatic adjustment of the shooting conditions is more finely controlled. Or more diverse image processing can be performed. Also, for example, when the sampling positions are arranged as shown in FIG. 21A for the subject image shown in FIG. 20, when the light amount of the strobe 4 is large as shown in FIG. There is a possibility that the brightness value of the subject d1 that is short in distance is saturated and the subject d1 cannot be clearly detected. On the other hand, when the light amount of the strobe 4 is small, the brightness value of the subject d3 that is farthest in distance cannot be distinguished from noise. Although the subject d3 may not be detected, the third pattern in which the preliminary photographing with the emission of the strobe light 4 is performed a plurality of times while changing the light amounts thereof,
Each of the subjects d1 to d3 can be appropriately detected from a plurality of flash emission images a thus obtained.

In the case of the third pattern, it is preferable that a plurality of preliminary shots are performed for each light quantity, and that the addition be performed and the averaging process be performed, thereby reducing errors and improving accuracy. It becomes possible.

In the case of the second pattern of the sequence between the preliminary photographing and the main photographing shown in FIG. 17, the image of the main photographing can be used as the image b when the strobe is not fired. Preliminary photographing without light emission can be omitted.

In the above-described embodiment, an example has been described in which the subject image is divided into two parts, a main part area and a background part area, from two images, that is, the image a with flash light emission and the image b with no flash light emission. For example, the division processing unit 35 can create a histogram of the luminance change appearing between the image a when the flash is emitted and the image b when the flash is not emitted, and can divide the subject into three or more from the histogram. That is, similar to the case where the preliminary photographing with the emission of the strobe light 4 is performed a plurality of times while changing the light amounts thereof, the subject image as shown in FIG. From each subject d
1 to d3 can be individually cut out, whereby the automatic adjustment of the photographing conditions can be more finely controlled, or more various image processing can be performed.

[0103]

As described above in detail, according to the electronic camera of the present invention, it is possible to execute the automatic adjustment of the photographing condition while reliably targeting the main part area, or it requires skill and considerable labor. Without the need, etc., according to the purpose, such as to be able to easily perform image processing such as performing different processing in the main part area and the background part area,
Based on the difference in the influence rate of the irradiation light, it is possible to execute, at an optimal timing, preliminary photographing for dividing the subject image into, for example, a main part region and a background part region.

[Brief description of the drawings]

FIG. 1 is an external view of an electronic camera according to an embodiment of the present invention.

FIG. 2 is a detailed configuration diagram of the inside of the electronic camera of the embodiment.

FIG. 3 is an image of a subject for explaining a dividing function of the electronic camera of the embodiment.

FIG. 4 is a diagram showing a result of dividing the subject image of FIG. 3 into a main part and a background part.

FIG. 5 is an exemplary flowchart illustrating an operation procedure when setting a shooting mode / condition of the electronic camera according to the embodiment.

FIG. 6 is an exemplary flowchart illustrating the operation procedure of the electronic camera according to the embodiment at the time of preliminary shooting processing.

FIG. 7 is an exemplary view for explaining the principle of detecting the distance of the subject of the electronic camera of the embodiment.

FIG. 8 is an exemplary flowchart showing the operation procedure of the electronic camera of the embodiment at the time of actual shooting processing.

FIG. 9 is an exemplary view for explaining an automatic adjustment function of a shooting condition (AF area) of the electronic camera according to the embodiment.

FIG. 10 is an exemplary view for explaining an automatic adjustment function of a photographing condition (flash irradiation area) of the electronic camera according to the embodiment.

FIG. 11 is an exemplary view for explaining an automatic adjustment function of shooting conditions (focal length) of the electronic camera according to the embodiment.

FIG. 12 is an exemplary view for explaining an example in which different sensitivity processing is performed on a main part and a background part of the electronic camera of the embodiment.

FIG. 13 is an exemplary view for explaining an example in which different recording processes are performed on a main part and a background part of the electronic camera of the embodiment.

FIG. 14 is an exemplary flowchart showing the operation procedure at the time of display / re-recording processing of the electronic camera of the embodiment.

FIG. 15 is an exemplary background image for explaining the composition processing of the electronic camera according to the embodiment;

16 is a diagram showing a result of synthesizing the background image of FIG. 15 and the clipped main part image.

FIG. 17 is an exemplary view showing a variation of a sequence between preliminary shooting and main shooting of the electronic camera of the embodiment.

FIG. 18 is an exemplary view showing a variation of a sequence of preliminary photographing by the electronic camera of the embodiment.

FIG. 19 is an exemplary view showing a shooting situation for explaining an example in which the subject image of the electronic camera of the embodiment is separated into at least two or more regions.

FIG. 20 is an exemplary view showing the subject image for explaining an example in which the subject image of the electronic camera of the embodiment is separated into at least two or more regions;

FIG. 21 is an exemplary view for explaining an effect of executing a plurality of times of preliminary photographing with flash emission of the electronic camera according to the embodiment while changing the light amounts thereof;

[Explanation of symbols]

 Reference Signs List 1 camera body 2 lens barrel 3 electronic viewfinder (EVF) 4 strobe 5 release button 6 mode dial 7 cross key 8 color liquid crystal display (LCD) 9 zoom lens 10 AF Focus) lens 11 ... aperture 12 ... optical zoom unit 13 ... AF mechanism 14 ... shutter 15 ... CCD two-dimensional color image sensor (CCD) 16 ... imaging circuit 17 ... A / D converter 18 ... image processing unit 19 ... electronic zoom unit 20 ... Buffer memory 21 ... Liquid crystal controller 22 ... Compressor / decompressor 23 ... Recording medium 24 ... Finder image generator 25 ... Liquid crystal controller 26 ... Strobe control circuit 27 ... Light emitting unit 28 ... Motor 29 ... Strobe cover 30 ... System controller 31 ... Operation Unit 32: Shooting control unit 33: Image separation control unit 34: AF control unit 35: AE control unit 36 zoom control unit 37 strobe control unit 38 image separation unit 39 separation information storage unit 40 luminance change detection unit 41 separation processing unit

Claims (7)

[Claims] 1. An electronic camera for capturing an image of a subject by a semiconductor imaging device, comprising: an auxiliary light irradiating unit for irradiating an auxiliary light; and a first preliminary photographing unit for performing a preliminary image of the subject using the auxiliary light irradiating unit. Second preliminary photographing means for performing preliminary photographing on the subject without using the auxiliary light irradiating means after the first preliminary photographing means performs preliminary photographing; and the first and second preliminary photographing. 2 imaged by means
Detecting means for detecting a change in brightness between two subject images; separating means for separating the subject image into a main part area and a background part area based on the brightness change detected by the detecting means; and a main part separated by the separating means. A photographing condition setting unit that performs setting of a photographing condition for a partial region; and a main photographing unit that performs a main photographing of the subject based on the photographing condition set by the photographing condition setting unit. An electronic camera characterized by the following. 2. An electronic camera for capturing an image of a subject by a semiconductor imaging device, comprising: an auxiliary light irradiating unit for irradiating auxiliary light; and a first preliminary photographing for performing a preliminary photographing of the object without using the auxiliary light irradiating unit. Means for performing preliminary photographing by the first preliminary photographing means, and then performing preliminary photographing for the subject using the auxiliary light irradiating means; and the first and second preliminary photographing means 2 imaged by means
Detecting means for detecting a change in luminance between two subject images; separating means for separating the subject into a main part area and a background part area based on the luminance change detected by the detecting means; and a main part separated by the separating means A photographing condition setting unit that performs setting of a photographing condition for an area; and a main photographing unit that performs main photographing of the subject based on the photographing condition set by the photographing condition setting unit. Electronic camera featuring. 3. An electronic camera for capturing an image of a subject by a semiconductor imaging device, an auxiliary light irradiating unit for irradiating an auxiliary light, a main photographing unit for performing a main photographing of the subject, and an execution of the main photographing by the main photographing unit A first preliminary photographing unit that performs preliminary photographing on the subject by using the auxiliary light irradiating unit; and after performing the preliminary photographing by the first preliminary photographing unit, without using the auxiliary light irradiating unit. A second preliminary photographing unit for performing preliminary photographing on the subject; and 2 images photographed by the first and second preliminary photographing units.
Detecting means for detecting a change in luminance between the two subject images; separating means for separating the subject image into a main part area and a background part area based on the luminance change detected by the detecting means; An electronic camera, comprising: a post-processing unit that performs different image processing or encoding processing on a subject image in a main part region and a background part region separated by the separation unit. 4. An electronic camera that captures a subject image using a semiconductor image sensor, an auxiliary light irradiating unit that irradiates an auxiliary light, a main photographing unit that performs a main photographing of the subject, and an execution of the main photographing by the main photographing unit. A first preliminary photographing unit that performs preliminary photographing on the subject without using the auxiliary light irradiating unit; and after executing the preliminary photographing by the first preliminary photographing unit, uses the auxiliary light irradiating unit to perform the preliminary photographing. A second preliminary photographing means for performing preliminary photographing on the subject, and a second photographing means which is photographed by the first and second preliminary photographing means.
Detecting means for detecting a change in brightness between two subject images; separating means for separating the subject into a main area and a background area based on the brightness change detected by the detecting means; and a subject imaged by the main photographing means An electronic camera, comprising: post-processing means for performing different image processing or coding processing on an image in a main part area and a background part area separated by the separation means. 5. An electronic camera for capturing an image of a subject by a semiconductor image pickup device, an auxiliary light irradiating unit for irradiating an auxiliary light, a main photographing unit for performing a main photographing of the subject, and an execution of the main photographing by the main photographing unit. Then, a preliminary photographing unit that performs preliminary photographing on the subject using the auxiliary light irradiating unit,
Detecting means for detecting a change in brightness between two subject images; separating means for separating the subject into a main area and a background area based on the brightness change detected by the detecting means; and a subject imaged by the main photographing means An electronic camera, comprising: post-processing means for performing different image processing or coding processing on an image in a main part area and a background part area separated by the separation means. 6. An electronic camera for photographing a subject image by a semiconductor image pickup device, wherein auxiliary light irradiating means for irradiating auxiliary light, and preliminary photographing of the object using the auxiliary light irradiating means so that the light emission amounts are different from each other. A first preliminary photographing unit that executes a plurality of times, a second preliminary photographing unit that performs a preliminary photographing of the subject without using the auxiliary light irradiating unit, and at least one obtained by the first and second preliminary photographing units. Detecting means for comparing three or more subject images to detect a change in brightness; and separating means for separating the subject into a plurality of regions based on the brightness change detected by the detecting means. Electronic camera. 7. The method according to claim 6, wherein the first and second preliminary photographing are performed before or after the main photographing.
Electronic camera as described.