JP2002218480A - Image photographing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To respectively and suitably make a decision about the state of an object in a photographic preparation mode and an image recording mode. SOLUTION: A scene discriminating part 31 performs a color fogging discrimination by using data thinned from image data outputted from an imaging part 21 at 24-pixel pitch in the photographic preparation mode, and meanwhile, by using data thinned at 4-pixel pitch in the photographing operation mode.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image photographing apparatus for photographing an object, and more particularly to an image photographing apparatus having a function of judging a state relating to the object and correcting image data obtained by imaging the object based on the judgment result. The present invention relates to an imaging device.

[0002]

2. Description of the Related Art Conventionally, in an image photographing apparatus such as a camera,
When the shutter button is half-pressed and the lock switch is turned on, the mode shifts to a shooting preparation state, and when the shutter button is further pressed and the release switch is turned on, shooting, that is, image recording is performed. .

[0003] Among cameras, a digital still camera that captures an image of an object using an image pickup device such as a CCD or the like has a CCD reading method such that reading is performed in a monitoring mode in a shooting preparation state, and reading is performed in an all-pixel reading mode in recording an image. The following has been proposed (see JP-A-11-298768). In the camera described in this publication, the number of data to be output is reduced by performing pixel addition in the monitoring mode as compared with that in the all-pixel reading mode, thereby achieving high-speed processing. At that time, the signal level changes due to pixel addition, so by lowering the level by the amount corresponding to the addition,
Calculations such as control values for correcting exposure and color can be similarly performed in both modes.

[0004]

The camera disclosed in the above-mentioned prior art is merely a camera in which the control values for correcting the exposure and the color in the photographing preparation state and during the image recording are shared.

On the other hand, it is desired for an image photographing apparatus to judge a state relating to a subject and to perform a correction process on image data output from an image pickup device based on the judgment result.

Therefore, the determination and the correction process are also described as follows.
It is preferable to perform the processing according to a suitable procedure in each of the shooting preparation state and the image recording.

[0007] The present invention has been made in view of the above,
It is an object of the present invention to provide an image photographing apparatus that can appropriately determine a state of a subject in a photographing preparation state and when recording an image.

Another object of the present invention is to provide an image photographing apparatus capable of suitably performing a correction process on image data in a photographing preparation state and at the time of image recording.

[0009]

According to a first aspect of the present invention, a plurality of photoelectric conversion elements are two-dimensionally arranged, an image pickup means for picking up an image of a subject and outputting image data of the subject, and Operable operation means, display means for displaying an image, and, in response to a first operation on the operation means, shifting to a shooting preparation state, which is a stage prior to shooting,
An operation control unit configured to execute a shooting operation for image recording in response to a second operation performed on the operation unit in the shooting preparation state; and performing a predetermined process on image data output from the imaging unit in the shooting preparation state. A first state determination unit that determines a state related to a subject using data obtained by performing the second operation on the operation unit; a predetermined state is added to image data output from the imaging unit; A second state determination unit that determines a state of the subject using data obtained by performing processing different from the processing, and a first state determination unit that determines a state of the image data based on a determination result of the first state determination unit in the shooting preparation state. And when the second operation is performed on the operation means, based on the determination result by the second state determination means, Image data correction means for performing a second correction process on image data, and display control means for displaying an image of a subject on the display means based on the image data on which the first correction process has been performed in the shooting preparation state When,
Recording control means for recording the image data subjected to the second correction processing in the recording means when executing the photographing operation.

[0010] According to this configuration, the first to the operating means.
In response to the above operation, the process shifts to a shooting preparation state, which is a stage prior to shooting, and in this shooting preparation state, the state relating to the subject is changed to a first state using data obtained by performing predetermined processing on image data output from the imaging unit. The image data is subjected to a first correction process based on the determination result, and an image of the subject is displayed on the display device based on the image data subjected to the first correction process. .

On the other hand, when a photographing operation for image recording is executed in response to the second operation on the operation means in the photographing preparation state, and the second operation is applied to the operation means,
The state relating to the subject is determined by the second state determination unit using data obtained by performing processing different from the above-described predetermined processing on the image data output from the imaging unit, and a second state determination is performed on the image data based on the determination result. Is performed, and the image data that has been subjected to the second correction processing is recorded in the recording means.

As described above, in the photographing preparation state, the state relating to the subject is determined using data obtained by performing predetermined processing on the image data output from the imaging means, while the second state is determined by the operation means. When an operation is performed and a shooting operation for image recording is performed, a state regarding the subject is determined using data obtained by performing processing different from the above-described predetermined processing on image data output from the imaging unit. You.

Therefore, in the photographing preparation state, since the image of the subject is displayed on the display means, high-speed judgment is required. As a predetermined process, a process capable of high-speed judgment is performed. When the operation is performed, since an image is recorded, a high-precision determination is required. As a process different from the predetermined process, a process capable of performing a high-precision determination is performed. A suitable determination is made for each of the and the execution of the shooting operation.

As the recording means, a recording medium built in the apparatus or an external recording medium detachable from the apparatus can be adopted.

According to a second aspect of the present invention, in the image photographing apparatus according to the first aspect, the first state determining means performs the predetermined processing as an image output from each of the photoelectric conversion elements of the imaging means. A process of extracting data decimated at a predetermined pitch from the data is performed, and a state related to the subject is determined using the extracted data. The second state determination unit performs processing different from the predetermined processing as described above. A process for extracting data thinned out at a pitch smaller than the predetermined pitch from image data output from each of the photoelectric conversion elements of the imaging means, and determining a state relating to a subject using the extracted data. It is characterized by.

According to this configuration, in the photographing preparation state, a process of extracting data decimated at a predetermined pitch from image data output from each photoelectric conversion element of the imaging means is performed as a predetermined process. When performing an action,
As a process different from the predetermined process, a process of extracting data thinned out from the image data at a pitch smaller than the predetermined pitch is performed.

Thus, when the camera is ready for shooting,
While it is possible to make the determination faster than when performing the shooting operation, when performing the shooting operation, it is possible to perform the determination with higher accuracy than when in the shooting preparation state. Suitable determinations are made for each time the shooting operation is performed.

According to a third aspect of the present invention, in the image photographing apparatus according to the first aspect, the first state determining means performs the predetermined processing by setting the imaging means to m ( m is an integer equal to or greater than 2), and the state of the subject is determined using the image data of each block.
The state determination unit performs processing different from the predetermined processing,
Each of the image pickup units is composed of a plurality of photoelectric conversion elements.
It is characterized in that a process for dividing into blocks (n is an integer of m <n) is performed, and a state relating to a subject is determined using image data of each block.

According to this configuration, in the photographing preparation state, a process of dividing the imaging means into m (m is an integer of 2 or more) blocks each including a plurality of photoelectric conversion elements is performed as a predetermined process. On the other hand, when performing a shooting operation,
As a process different from the above-described predetermined process, the imaging means is formed of a plurality of photoelectric conversion elements, each of which is n (n is an integer of m <n)
Processing for dividing into blocks is performed.

Thus, when the camera is ready for shooting,
It is possible to make a high-speed determination using the image data of a smaller number of blocks as compared to when the shooting operation is performed, while, when performing the shooting operation, it is possible to determine a larger number of blocks for each block than in the shooting preparation state. The determination can be made with high accuracy using the image data, and a suitable determination can be made in each of the shooting preparation state and the shooting operation execution.

According to a fourth aspect of the present invention, in the image photographing apparatus according to any one of the first to third aspects, the first state determining means and the second state determining means each include a state relating to the subject. , At least one of a photographing scene, a position of a main subject, and a position of a person.

According to this configuration, in the photographing preparation state, since the image of the subject is displayed on the display means, a high-speed determination is required. Therefore, a process capable of performing the high-speed determination is performed as a predetermined process. On the other hand, when the photographing operation is performed, an image is recorded, so that a high-precision determination is required. In the preparatory state and the execution of the photographing operation, a suitable judgment is made, that is, at least one of the photographing scene, the position of the main subject, and the position of the person is determined.

In this configuration, in the photographing preparation state, since the image of the subject is displayed on the display means, high-speed judgment is required. Therefore, the first state judgment means determines the photographing scene, the position of the main subject and the person. One of the positions,
For example, when the photographing operation is performed by determining only the position of the main subject and the image is recorded, high-precision determination is required. Therefore, the second state determination unit determines the photographing scene, the position of the main subject, and the person. May be determined.

According to a fifth aspect of the present invention, a plurality of photoelectric conversion elements are two-dimensionally arranged, an image pickup means for picking up an image of a subject and outputting image data of the subject, and an operation operable from outside. Means, display means for displaying an image, and, in response to a first operation on the operation means, shifting to a photographing preparation state, which is a stage prior to photographing, and a second operation on the operation means in the imaging preparation state. Operation control means for executing a shooting operation for image recording in response thereto, first state determination means for determining a state relating to a subject using image data output from the imaging means in the shooting preparation state; Means for the second
When the operation of is performed, a second state determination unit that determines a state relating to a subject using image data output from the imaging unit, and a second state determination unit that determines a state of the image data based on a determination result by the first state determination unit. A first image data correction unit for performing a first correction process, and a second image data for performing a second correction process different from the first correction process on the image data based on a determination result by the second state determination unit Correction means, display control means for displaying an image of a subject on the display means based on the image data subjected to the first correction processing in the shooting preparation state, and second display means for executing the shooting operation. Recording means for recording the corrected image data in the recording means.

According to this configuration, the first operation means
In response to the operation of (1), the state shifts to a shooting preparation state, which is a stage prior to shooting, and in this shooting preparation state, a state relating to the subject is determined by the first state determination means using image data output from the imaging means. The first correction processing is performed on the image data by the first image data correction means based on the image data, and the image of the subject is displayed on the display means based on the image data on which the first correction processing has been performed.

On the other hand, when a photographing operation for image recording is performed in response to the second operation on the operation means in the photographing preparation state, and the second operation is applied to the operation means,
The state relating to the subject is determined by the second state determination unit using the image data output from the imaging unit, and a second correction process different from the first correction process is performed on the image data based on the determination result. The image data subjected to the second correction processing is recorded in the recording means when the photographing operation is performed by the data correction means.

As described above, in the photographing preparation state, the first correction processing is performed on the image data output from the image pickup means, while the second operation is performed on the operation means to record the image. Is performed, a second correction process different from the first correction process is performed on the image data output from the imaging unit.

Therefore, in the photographing preparation state, since the image of the subject is displayed on the display means, high-speed correction processing is required. As a first correction processing, processing that can be performed at high speed is performed. , When performing a shooting operation,
Since the image is recorded, high-precision correction processing is required. Therefore, processing that can be performed with high precision is performed as the second correction processing, so that the camera is ready for shooting and when the shooting operation is performed. Thus, a suitable correction process is performed for each.

As the recording means, a recording medium built in the apparatus or an external recording medium detachable from the apparatus can be adopted.

According to a sixth aspect of the present invention, in the image photographing apparatus of the fifth aspect, the second image data correcting means performs a correction process on the image data for a plurality of characteristics. The one image data correcting means is characterized in that it corrects only some of the plurality of characteristics.

According to this structure, the second means is provided for the operation means.
When the photographing operation for recording an image is performed by adding the above operation, correction processing is performed on the image data output from the image pickup means for a plurality of characteristics. The image data output from is corrected only for some of the plurality of characteristics.

Accordingly, in the photographing preparation state, since the image of the subject is displayed on the display means, high-speed correction processing is required. Therefore, while only a part of the plurality of characteristics is corrected, the correction processing is performed. When performing a shooting operation,
Since images are recorded, high-precision correction processing is required. By performing correction processing on a plurality of characteristics, correction is performed on characteristics that are suitable for the respective conditions in the shooting preparation state and when the shooting operation is performed. Processing will be performed.

According to a seventh aspect of the present invention, in the image photographing apparatus of the sixth aspect, the second image data correcting means includes at least an exposure value, a color balance characteristic, and a γ characteristic as the plurality of characteristics. The first image data correction means is configured to perform a correction process on an exposure value and a color balance characteristic among the plurality of characteristics.

According to this configuration, in the photographing preparation state, an image of the subject is displayed on the display means at a predetermined level of image quality by performing correction processing on the exposure value and the color balance characteristics. On the other hand, when the photographing operation is performed, a correction process is performed on at least a plurality of characteristics including an exposure value, a color balance characteristic, and a γ characteristic, so that an image is recorded on the recording unit with high image quality.

According to an eighth aspect of the present invention, in the image photographing apparatus according to the sixth or seventh aspect, the first image data correction means is configured to correct the image data based on a determination result by the first state determination means. When the calculated correction amount is equal to or more than a predetermined level, the first correction process is performed using the predetermined level as a correction amount.

According to this configuration, when the correction amount for the image data is calculated based on the determination result by the first state determination unit, if the calculated correction amount is equal to or more than the predetermined level, the predetermined level is used as the correction amount. By performing the first correction process on the image data, a weak correction process is performed, and an image of the subject close to the state captured by the imaging unit is displayed on the display unit. The tendency of the image possessed by is better understood by the photographer.

[0037]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a digital still camera as an embodiment of an image photographing apparatus according to the present invention will be described. FIG. 1 is a perspective view showing an appearance of the digital still camera, and FIG. 2 is a block diagram showing functional blocks of the digital still camera.

As shown in FIG. 1, the digital still camera 1 includes a camera body 2 and a lens barrel 3. On the back side of the camera body 2, an image display unit 4 composed of, for example, an LCD and an external memory 8 such as a card type memory are provided.
A memory mounting section 5 to which (FIG. 2) can be mounted is provided, and a shutter button 6 is provided on the upper surface thereof. Further, inside the lens barrel 3, a photographing optical system 7 composed of a lens group is provided.
Are arranged.

The digital still camera 1 has a function of capturing an image of a subject, taking in image data representing the image of the subject, performing correction processing such as color balance and contrast on the image data, and recording the image data.

As the correction processing for the image data, a standard correction processing is performed in consideration of the existence of various image output devices, for example, a CRT, an LCD and a printer.

The shutter button 6 is, as shown in FIG.
A lock switch 11 and a release switch 12 are provided. The lock switch 11 is turned on when the shutter button 6 is half-pressed.
When 1 is turned on, the state shifts to the shooting preparation state. The release switch 12 is turned on when the shutter button 6 is further depressed from a half-pressed state and is fully depressed. When the release switch 12 is turned on, shooting (image recording) is performed.

The image display unit 4 functions as an electronic viewfinder for displaying image data being picked up by the image pickup unit 21 in real time in a shooting preparation state, and displays an image to be recorded when shooting is performed. It has become so.

In FIG. 2, a photographing optical system 7 focuses and zooms on a subject, and forms an image of the subject on a light receiving surface of the image pickup unit 21. The external memory 8 is a removable external recording medium, and may be, for example, a known card-type memory having an EEPROM such as a flash memory, a flexible disk (FD), or the like.

The image pickup section 21 has, for example, R, G, B color filters disposed in front of a plurality of two-dimensionally arranged photoelectric conversion elements (for example, a CCD in the present embodiment, hereinafter also referred to as “pixels”). A color area sensor, an analog signal processing circuit, an A / D converter, and the like are provided to output a color image of a subject and output image data. The output image data is temporarily stored in an image data temporary storage unit 22. Is stored. The photoelectric conversion element is not limited to the CCD, but may be a CMOS or the like.

The imaging control unit 23 determines the imaging conditions such as the exposure time and the gain in the imaging unit 21 at the time of the next capturing of the imaging data based on the information stored in the imaging data temporary storage unit 22 and the like. 21 for setting the image reading mode.

The image data processing section 24 includes functional blocks 31 to 34 and has the following functions.

A function of performing predetermined processing on image data output from the imaging unit 21 and then determining a state of a subject including a photographic scene. Here, a predetermined process (for example, a thinning rate of image data, etc.) performed on image data output from the imaging unit 21 is different between the time of the shooting preparation state and the time of executing shooting.

A function of performing correction processing on image data so that the image becomes an appropriate image for the determined state relating to the subject.

The scene determination section 31 of the image data processing section 24
Has the following functions; a function of dividing image data output from the imaging unit 21 into a plurality of blocks, and determining a color cast state of the image based on color information of each block; A function of detecting the presence or absence of a person in an image; a function of creating a color histogram for each block for color cast determination and determining a main subject and a shooting scene based on the information of the color histogram and information on the presence or absence of a person.

The image data correction section 32 includes a scene determination section 3
The image data is subjected to correction processing with respect to various characteristics in accordance with the result of the determination made by step 1, for example, the color cast state, the main subject, the shooting scene, and the like. The characteristics include, for example, an exposure value, a color balance, a γ characteristic, and an edge enhancement process.

The image information setting section 33 sets, as image information, information relating to image determination such as a shooting scene and information relating to image correction such as a correction amount of image data. The image data synthesizing unit 34 associates the corrected image data corrected by the image data correcting unit 32 with the image information set by the image information setting unit 33 to create one recording data. .

The sequence control unit 25 controls a photographing sequence such as photographing and data acquisition. For example, when the lock switch 11 is turned on, a transition is made to a photographing preparation state, and when the release switch 12 is turned on, a photographing operation is executed. In response to the completion of the image pickup, the operation of the image data correction unit 32 is started.

The display control unit 26 includes an image data correction unit 32
The image is displayed on the image display unit 4 based on the image data subjected to the correction processing according to (1). In the shooting preparation state, the image corrected at high speed is displayed in real time, and the image to be recorded when the shooting is executed Is displayed. Recording control unit 27
Is for recording the recording data created by the image data synthesizing unit 34 in the external memory 8.

The function blocks 21 to 27 in FIG.
One or more CPU, EEPROM, RAM, RO
It is composed of a memory such as M and various electronic circuits. The detailed operation of each of the functional blocks 21 to 27 will be described later.

Next, the image data output from the imaging section 21 will be described with reference to FIGS. FIGS. 3 and 4 are views showing the arrangement of CCDs in the imaging unit 21.

In FIG. 3, the area sensor of the imaging section 21 has an all-pixel mode and a thinning-out mode as an image reading mode. When the area sensor is set to the all-pixel mode, it outputs data of all pixels, and is set to the thinning mode. Then
It outputs data thinned out at a predetermined pixel pitch in the Y direction.
Note that data of all pixels is output in the X direction. When the thinning mode is set to the three-pixel pitch, data of the pixel row indicated by the arrow shown in FIG. 3 is output.

Therefore, in the thinning mode, the image data processing unit 24 performs a process of thinning out the pixel data in the X direction at the same pixel pitch as the Y direction on the image data output from the imaging unit 21, and performs the thinning. The processing described later is performed using the data thus obtained. Thus, in the thinning mode, the size ratios of the images in the X and Y directions are the same.

That is, in the thinning mode, the image data is reduced only in the Y direction when outputting pixel data from the area sensor, and the image data is reduced in the X direction during data processing, thereby reducing the image data in both the X and Y directions. I am trying to do it.

In general, as shown in FIG. 3, the color area sensor has a color filter of any one of R, G, and B disposed in front of each pixel. You can only get information. Therefore, in the present embodiment, color information of two colors that do not exist for each pixel is
It is obtained by performing data interpolation using information on the surrounding color.

In FIG. 4, for example, for the color information R ₂₂ and G ₂₂ of the pixel to which the color information B ₂₂ is output, for example, R ₂₂ = (R ₁₁ + R ₃₁ + R ₁₃ + R ₃₃ ) / 4 G ₂₂ = (G ₂₁ by _{+ G 12 + G 32 + G} 23) / 4 performs data interpolation using the data of four pixels around. In this way, R, G, and B color information is obtained for all pixels.

Next, the determination of the color cast will be described with reference to FIGS. FIG. 5 is a diagram illustrating an example of a divided block, and FIG. 6 is a diagram illustrating an example of a color cast determination result.

The color cast is determined by dividing the area sensor of the image pickup section 21 into a plurality of blocks and for each block. Therefore, if there is a color cast in all the blocks, it is determined as "color cast of the light source", and if only some of the blocks have a color cast, it is determined as "bias of a specific color". This makes it possible to correct only the color cast of the light source.

In the photographing preparation state, as shown by the solid line in FIG. 5, the image is divided into a total of 6 blocks of 3 blocks in the X direction and 2 blocks in the Y direction.
As shown by a solid line and a broken line in FIG. 5, the data is divided into a total of 24 blocks of 6 blocks in the X direction and 4 blocks in the Y direction.

That is, in the photographing preparation state, the image is divided into blocks coarser than when photographing is performed. This is because it is necessary to display an image on the image display unit 4 in real time in the shooting preparation state, and it is not necessary to record the image. Therefore, a higher processing time than accuracy is required.

In the present embodiment, the color cast is determined using the average value of each color of the image data. When using this average value, if there is no color cast, Is used. However, Rave
(n), Gave (n) and Bave (n) are R,
This is the average value of the G and B data. In addition, n is a block number, and n = 1 to 6 in a shooting preparation state, and n = 1 to 24 in a shooting execution.

The sensitivity difference of each color is corrected in hardware by an analog signal processing circuit provided in the image pickup unit 21. Therefore, when a white or gray test chart is picked up by the image pickup unit 21, the above equation (1) is obtained. , (2) from the imaging unit 21.

Then, the value BL (n) = (Kr (n), Kb (n)) (3) of each block is plotted on the two-dimensional coordinates composed of the axes Kr and Kb as shown in FIG. It is determined whether or not the color is cast based on the bias of the plotted points.

In FIG. 6, when there are many plot points on the lower right side of the boundary line L, it is determined that there is a reddish color cast, and when there are many plot points on the upper left side of the boundary line L, the bluish color cast is present. Is determined, and when the plot points are substantially uniformly distributed on both sides of the boundary line L, it is determined that there is no color cast.

The color cast correction amount is calculated based on the center of gravity of the points plotted in the same color cast area. In the case of FIG. 6, the color cast correction amount is obtained based on the barycentric values of BL (1), BL (2), BL (3), BL (5), and BL (6).

For example, when the center of gravity value is (Kr, Kb) = (0.5, 0.2) (4), a correction coefficient for correcting a state without color fog is given by: Δr = 0.3 / 0.5 = 0.6. (5) Δg = 1 (6) Δb = 0.3 / 0.2 = 1.5 (7)

Here, since the color casts of red (R) and blue (B) located at both ends on the color spectrum are determined and corrected, the green (G) is determined as shown in the above equation (6). Correction coefficient Δg
= 1. Also, as shown in the above equations (5) and (7),
1/3 = 0.3.

If it is determined that there is no color cast, Δr = 1 Δg = 1 Δb = 1.

As described above, the image data output from the imaging unit 21 is divided into a plurality of blocks, and the presence or absence of color cast is determined by obtaining the average color value of the pixel for each block. If a color cast of a light source or the like has occurred, the color cast is corrected. By correcting the color cast of the light source, a person, that is, a skin color can be accurately detected.

Next, an operation procedure of the digital still camera 1 will be described with reference to a flowchart. FIG.
9 is a flowchart of a main routine of the operation procedure.

When the power is turned on, first, the photoelectric conversion element (CCD in this embodiment) of the image pickup section 21 and the image display section 4
(Step # 100), and then the shutter button 6 is half-pressed and the lock switch 11 is turned on (NO in # 105). ),stand by.

Then, when the lock switch 11 is turned on (YES in # 105), a shooting preparation state is established, and the process shifts to a first shooting condition setting subroutine, where shooting conditions in the shooting preparation state are set (FIG. 9). # 110).

FIG. 8 is a flowchart of the first imaging condition setting subroutine. In the figure, first, the imaging unit 21
Is set to the thinning mode (# 2)
00) Then, the CCD gain of the imaging unit 21 is set to high sensitivity (for example, 8 times in the present embodiment) (# 20).
5), is returned.

In the shooting preparation state, high-speed processing is required to display an image on the image display unit 4 in real time. Therefore, by setting the thinning mode, the reading time of the image data can be shortened, and by setting the CCD gain to high sensitivity, the exposure time of the CCD can be shortened, thereby realizing high-speed processing. are doing.

Returning to FIG. 7, image data captured by the image capturing section 21 under the set image capturing conditions is fetched and stored in the image capturing data temporary storage section 22 (# 115).

Next, as described with reference to FIGS. 5 and 6, the image data is thinned out in the X direction (# 120).
The R, G, B data of each pixel is obtained by pixel data interpolation (# 125).

Next, the process proceeds to a first scene discrimination processing subroutine, and a photographing scene determination in a photographing preparation state is performed (# 130).

FIG. 9 is a flowchart of the first scene determination processing subroutine. In the figure, first, image data is thinned out at a predetermined pixel pitch (for example, 8 in the present embodiment) and taken in (# 220). Accordingly, in the present embodiment, since the data is thinned out at a three-pixel pitch at the time of reading, the image data thinned out at a 24-pixel pitch is used among the image data captured by the imaging unit 21.

Next, as described with reference to FIG. 5, the image data is divided into a total of six blocks, three blocks in the X direction and two blocks in the Y direction (# 225).
Based on (1) to (3), the value of each block is determined to determine the color cast of the image (# 230), and the correction coefficients Δr, Δg, Δb are determined (# 235).

Then, using this correction coefficient, R = Δr · R ′ (8) G = Δg · G ′ (9) B = Δb · B ′ (10) Is performed (# 24)
0). Here, R ', G', B 'are image data before correction, R,
G and B are image data after correction.

Subsequently, the corrected image data R, G, B
Using, , The image data based on the R, G, B signals is converted into image data based on the hue H and the corrected saturation Q (# 24)
5). Here, the range of each value is 0 ≦ H ≦ (maximum value of R, G, B) and 0 ° ≦ Q ≦ 360 °.

Since the hue H is not affected by the change in luminance, it is effective for detecting an object whose luminance change is expected. The modified saturation Q has a feature that the saturation value increases in proportion to the lightness, and it can emphasize the skin of a person more than the saturation required from the Munsell color system, so the brightness is relatively high Suitable for detecting human skin.

Next, the range of the skin color is set to 0 ≦ H ≦ 0.4 (13) 50 ° ≦ Q ≦ 120 ° (14), and it is detected whether or not the value of each pixel is within the range of the skin color. As a result, the presence or absence of a person is detected (# 25
0).

Next, the continuity of the pixel data of the flesh-color pixels is determined, and flesh-color pixels that can be determined to be continuous are connected (# 255). Here, the connection of pixels refers to creating a skin color area by connecting pixels that can be determined to be continuous in flesh color in the horizontal direction in order to check the continuity of pixels in the horizontal direction.

In this case, when a plurality of pixels equal to or more than a predetermined value are continuous, and when it is determined that only a pixel equal to or less than a predetermined value (for example, one) is not a flesh color, the whole pixel including the one pixel is included. May be determined to be continuous.

Subsequently, in the flesh-color area composed of the linked flesh-color pixels, a predetermined size and a predetermined shape area are set as candidate areas where a human face is present (# 260), and the distribution and size of the flesh-color area are set. The main subject is provisionally determined based on the information such as the shape and the shape (# 265), and the process returns.

For example, when a plurality of skin color regions are arranged in the horizontal direction, it is determined that a plurality of human faces are arranged, and a plurality of main subjects may be set. Also, for example, 3
If the individual skin color areas form a vertically long isosceles triangle, it may be determined that the face and both hands are the same person, and the upper skin color area may be set as the main subject.

Returning to FIG. 7, the process then proceeds to a first image data correction subroutine, in which the image data is subjected to a correction process so that the provisionally determined main subject is suitably displayed on the image display unit 4. (# 135).

FIG. 10 is a flowchart of the first image data correction subroutine. In the figure, first, information such as the position of the tentatively determined main subject is taken in (# 28).
0) Then, exposure correction of the tentatively determined main subject is performed (# 285), and subsequently, correction of suppressed color cast is performed (# 290), and the process returns.

That is, although the correction relating to the color cast is performed, depending on the photographing scene such as, for example, the evening scene, an excessively corrected color cast results in an unnatural image. Specifically, the correction coefficients Δr, Δg, and Δb may be set to values close to 1. For example, when the obtained correction coefficient is less than 0.7, the correction coefficient is set to 0.7.

When the calculated correction coefficients Δr and Δb are 1.1
When the correction coefficient Δr and Δb are less than 0.9, the correction is performed by using the result obtained by multiplying by the predetermined coefficient α (for example, α = 0.95) when the value exceeds 0.9. Is also good.

Returning to FIG. 7, an image is displayed on the image display section 4 based on the corrected image data (# 140). Then, until the release switch 12 is turned on (# 1
45, NO), the shooting preparation state is continued, and
Step 140 is repeated.

As described above, since the main subject is provisionally determined and the image data is corrected so that the provisionally determined main subject becomes an appropriate image, an image display functioning as an electronic view finder is performed. A suitable image can be displayed on the unit 4.

When the release switch 12 is turned on in this photographing preparation state (YES in # 145), the process proceeds to the second photographing condition setting subroutine of # 150 to execute photographing (image recording).

FIG. 11 is a flowchart of the second imaging condition setting subroutine. In the figure, first, the imaging unit 2
The image reading mode of the area sensor No. 1 is set to the all pixel mode (# 300).
The gain is set to the optimum level (# 305), and the process returns.

The optimum level of the CCD gain is determined based on the light receiving level of the CCD in a shooting preparation state.
3 is a level at which the CCD having the maximum light receiving level does not overflow, for example.

The photographing is not performed frequently, but only when the release switch 12 is turned on.
Since image recording is performed, high accuracy is required rather than high speed. Therefore, by setting the all-pixel mode to improve the resolution of the image, the subsequent correction processing can be performed with high accuracy, and a high-resolution image can be obtained. Images can be obtained.

Returning to FIG. 7, the image data output from the image pickup section 21 under the set image pickup conditions is fetched and stored in the image pickup data temporary storage section 22. As described above, the R of each pixel is interpolated by the pixel data interpolation. , G, B data are obtained (# 155).

Next, the flow shifts to a second scene determination processing subroutine, where a shooting scene determination is performed (# 160).

FIG. 12 is a flowchart of the second scene determination processing subroutine. In the figure, first, image data obtained by thinning out image data at a predetermined pixel pitch (for example, 4 in the present embodiment) is captured (# 320). Accordingly, since the all-pixel reading mode is set, the image data thinned out at a 4-pixel pitch is used among the image data output from the imaging unit 21. That is, at the time of shooting, image data having a finer pixel pitch than in the shooting preparation state is used.

Next, as described with reference to FIG. 5, there are a total of 24 blocks of 6 blocks in the X direction and 4 blocks in the Y direction.
The image data is divided into blocks (# 325), and equation (1)
The color cast of the image is determined based on (3) (# 33)
0), and the correction coefficients Δr, Δg, and Δb are obtained (# 33).
5) Using this correction coefficient, the color cast of the image data is corrected by the above equations (8) to (10) (# 34).
0).

The determination of the color cast and the calculation of the correction coefficient are as follows.
This is performed in the same manner as the first scene determination processing subroutine (see FIG. 9) in the shooting preparation state, but can be performed with higher precision because the number of image data and the number of divided blocks are large.

Subsequently, the corrected image data R, G, B
Is used to convert the image data based on the R, G, and B signals into image data based on the hue H and the corrected saturation Q (# 345), and then, for each pixel, The presence or absence of a person is detected by detecting whether or not the value is within the range of the skin color set by the above equations (13) and (14) (# 3)
50).

Next, the flesh color pixels are connected around the candidate area of the person set in the first scene determination processing subroutine (# 355). Next, the shape of the flesh-color area composed of the connected flesh-color pixels is determined (# 360), and the colors around and inside the flesh-color area are further determined (# 3).
65), the face of the person is detected (# 370).

For example, since hair exists around the face of a person, a continuous area such as black, brown, gold, or white exists. Since the color cast has already been corrected for the image data, the hair can be easily determined by using the corrected image data.

Next, a color histogram is created for each of the blocks divided in # 325 (# 375), and a photographic scene is determined based on information on the presence or absence of a person and information on the color histogram (# 380), and the process returns. .

Here, with reference to Table 1, an example of the photographic scene determination for the information on the presence or absence of a person and the information of the color histogram will be described.

[0112]

[Table 1]

As shown in Table 1, the shooting scene is as follows.
In the present embodiment, for example, scene S1: snapshot, scene S2: portrait scene S3: commemorative photography scene S4: landscape photography scene S5: evening scene scene S6: night scene scene S7: Night view portrait, scene S8: sea, scene S9: fluorescent light source, scene S10: tungsten light source.

The snapshot of the scene S1 is determined when a general shooting scene is not determined as the following scenes S2 to S10.

The portrait of the scene S2 is for photographing a person large and beautifully, and is determined when the person's face exists in a large size and there is no color cast.

The commemorative photographing of the scene S3 is performed when a commemorative building or the like exists in the background of the person, and the person's face is present in a medium to small size, and is judged when there is no color cast.

The landscape photographing of the scene S4 is for photographing a landscape at a long distance, and is determined when there is no face of a person and no fog of a specific color exists on the entire screen.

The evening scene of scene S5 is for photographing a red-stained landscape or a person at sunset, and is determined when the ratio of red is high in a part of the image regardless of the presence or absence of the person.

The night view of the scene S6 is for photographing a light source or a building illuminated by the light source in a dark situation, and is determined when no person exists and a black portion and a white portion are mixed. .

The night scene portrait of scene S7 is for photographing a person with a night scene as a background, and is determined when a person's face exists in a medium to large size and a black portion and a white portion are mixed. .

The sea in the scene S8 has the sea as a background and may include a person. The sea is determined when the blue ratio is high in a part of the image regardless of the presence or absence of the person.

The fluorescent lamp light source of the scene S9 is photographed under a fluorescent lamp, and is determined when the blue-green cast by the fluorescent lamp has a high blue-green ratio in the entire image regardless of the presence or absence of a person.

The tungsten light source of the scene S10 is photographed under the tungsten light source, and is determined when the ratio of red in the entire image is high due to the red cast by the tungsten light source regardless of the presence or absence of a person.

Although not shown in Table 1, the photographic scene may be determined in consideration of information other than image data such as distance information to the subject and photographic magnification information.
As a result, scene determination can be performed with higher accuracy.

Returning to FIG. 7, following the second scene determination processing subroutine of # 160, the process proceeds to a second image data correction subroutine, in which a main subject is determined based on the determined photographic scene. Is applied to the image data (# 165).

FIG. 13 is a flowchart of the second image data correction subroutine. In the figure, first, information on the determined shooting scene is taken in (# 40).
0), information about the person is taken in (# 405),
The main subject is determined based on the information (# 41
0).

Next, the exposure value is corrected so that the determined exposure of the main subject is optimized (# 415). Here, the optimum exposure value is, for example, a value in which the average luminance Y of the main subject satisfies 100 ≦ Y ≦ 150 when the digital value is represented by 8 bits (0 to 255). The average luminance Y is obtained by the following equation (15), where R, G, and B are the image data of each color: Y = 0.299 · R + 0.587 · G + 0.114 · B (15)

Subsequently, an appropriate color cast correction is performed on the determined photographic scene (# 420), and γ corresponding to the photographic scene determined from a plurality (for example, four in the present embodiment) of γ correction curves. A correction curve is selected (# 425), and γ correction is performed based on the selected γ correction curve (# 4).
30), an edge enhancement process is performed using a filter corresponding to the determined shooting scene (# 435), and the process returns.

Here, an example of the correction processing performed on each of the determined photographing scenes will be described according to Table 2 with reference to FIG. 14 and FIG.

FIG. 14 is a graph showing a γ correction curve. In this embodiment, for example, γ = 1.2 shown in FIG. 14A and γ = 1.1 shown in FIG.
5, four types of γ = 1.3 shown in (c) and γ = 1.1 shown in (d) are stored in the memory in advance in a look-up table format. In addition, you may make it store with a mathematical formula instead of a table format.

FIGS. 15A and 15B show filters used in the edge enhancement processing. FIG. 15A shows a filter having a strong edge enhancement degree, FIG. 15B shows a filter having a medium edge enhancement degree, and FIG. This shows a filter having a weak edge enhancement degree.

[0132]

[Table 2]

As shown in Table 2, in the case of the snapshot of the scene S1, R, G, B
The normal white balance (WB) correction for performing the gain adjustment is performed, the standard correction (FIG. 14 (a)) having a medium contrast is performed as the γ correction, and the edge enhancement degree is set to the middle as the edge enhancement processing. Filter (Fig. 15)
Standard processing using (b)) is performed.

In the case of the portrait of the scene S2, skin color priority WB correction for adjusting R, G and B gains is performed as color balance correction so that the skin color of the face of the person is not impaired. In addition, in order to obtain an effect close to soft focus, a correction (FIG. 14 (d)) for weak contrast is performed as γ correction. The used processing is performed.

In the commemorative photographing of the scene S3, skin color priority WB correction for gain adjustment of R, G, B is performed as color balance correction so that the skin color of the face of the person is not impaired. In addition, since it is preferable to perform standard correction in terms of clarity of the image, a correction (FIG. 14A) that provides a moderate contrast is performed as the γ correction, and the edge enhancement degree is determined as the edge enhancement processing. Processing using a medium filter (FIG. 15B) is performed.

In the case of landscape photography of scene S4, since the entire screen is set as a subject rather than portrait photography, color balance correction is not performed to give priority to color reproducibility.
Further, since the angle of view is wide, the contrast and the edge cannot be seen clearly unless they are strengthened. Therefore, a correction (FIG. 14C) for obtaining a strong contrast is performed as the γ correction, and the edge is enhanced as the edge enhancement processing. Processing using a filter with a high degree (FIG. 15A) is performed.

In the case of the evening scene of scene S5, no color balance correction is performed so as not to impair the color reproduction of the evening scene. Further, assuming an angle of view as in commemorative photography (scene S3), a standard correction is preferable. Therefore, a correction (FIG. 14A) that provides a medium contrast is performed as the γ correction, and an edge enhancement process is performed. Processing using a filter having a medium emphasis degree (FIG. 15B) is performed.

In the case of the night view of the scene S6, the gain adjustment amount is reduced as compared with the normal color balance correction (gain correction coefficient is close to 1) so as not to impair the atmosphere of the night view.
The weak WB correction is performed, and a correction (FIG. 14 (b)) that provides a relatively weak contrast is performed as the γ correction, and a filter having a medium edge enhancement degree (FIG. 15 (b)) is performed as the edge enhancement processing. The used processing is performed.

In the case of the night view portrait of the scene S7, since the person is photographed in a night view, the exposure value of the person portion is corrected so as to be optimal. Further, in order not to spoil the atmosphere of the night view, weak WB correction is performed as color balance correction. In addition, since the photographing is performed by a person, a correction with a relatively low contrast (FIG. 14B) is performed as the γ correction, and a filter having a medium edge enhancement degree (FIG. 15B) is used as the edge enhancement processing. Is performed.

In the case of the sea in scene S8, summer is assumed,
In order not to impair the atmosphere of strong sunlight, color balance correction is not performed, and a correction (FIG. 14C) that provides a strong contrast is performed as the γ correction, and a filter with a strong edge enhancement degree is used as the edge enhancement processing ( FIG.
Processing using (a)) is performed.

In the case of the fluorescent lamp light source of scene S9, the color cast by the fluorescent lamp is corrected, and the normal WB correction is performed as the color balance correction, and the standard correction that provides a moderate contrast as the γ correction is performed. (FIG. 14A) is performed, and a standard process using a filter having a medium edge enhancement degree (FIG. 15B) is performed as the edge enhancement process.

In the case of the tungsten light source of the scene S10, the color cast is weakly corrected (the correction coefficient is close to 1, for example, 0.9) to leave a reddish atmosphere of tungsten light, and the WB is weak for color balance correction. Correction is performed. In addition, a standard correction (FIG. 14A) that provides a medium contrast is performed as the γ correction, and a filter having a medium edge enhancement degree (FIG. 15A) is used as the edge enhancement processing.
Standard processing using (b)) is performed.

Returning to FIG. 7, following the second image data correction subroutine of # 165, an image based on the corrected image data is displayed on the image display unit 4 (# 170). The process proceeds to set information on image determination and information on correction processing (# 175).

FIG. 16 is a flowchart of the image information data setting subroutine. In the figure, first, correction coefficients Δr, Δg, and Δb of each color are set (# 500), and then, a table R of a γ correction curve used for γ correction of each color is set.
t, Gt, and Bt are set (# 505), and data relating to the used edge emphasis filter is set (# 50).
8) Information about the determined shooting scene is set (# 510), information about the presence or absence of a person is set (# 515), and the number of persons is set (# 520).
The position and size of the person are set (# 525), the image information data end flag is set (# 530),
Is returned.

Returning to FIG. 7, following the image information data setting subroutine at # 175, at # 180, one piece of recording image data is created by associating the set image information data with the raw image data. .

FIG. 17 shows an example of the recording data.
FIG. 17 shows an example in which there are three persons. FIG.
The γ-correction curve set in # 505 of No. 6 may be set by a mathematical expression instead of a table format. Also,
The image information data end flag set in # 530 of FIG. 16 may be a predetermined code (for example, 1 of four consecutive bits). Further, data on the filter shown in FIG. 15 may be stored.

Returning to FIG. 7, when the recording data is recorded in the external memory 8 at # 185, the state shifts to a standby state. When # 185 ends, # 1
05.

As described above, according to the present embodiment, information relating to image determination of a photographed scene, a person, and the like, and information relating to correction processing such as color correction are stored. When an image is output by another device, such as a monitor display, a suitable image output can be made possible by using the stored information as described later.

In particular, it is very difficult to detect information about a person effective for performing a suitable image output based on only image data. On the other hand, when shooting, in addition to image data, distance information to the subject, shooting magnification information,
Since moving object information and the like can be obtained, person detection can be performed relatively easily by effectively using such information. Therefore, in the digital still camera 1, it is preferable to store information about a person and the like.

Here, an example of detection of moving object information and detection of a person using the moving object information will be described.

The moving object is detected by comparing the current image with the image before a predetermined time (for example, one second), and based on the variation of the average luminance Y during that time. The average luminance Y is obtained by the above equation (15), where each value of the color image signal is R, G, B.

First, the average value of the amount of change in the luminance Y in the predetermined areas at the four corners of the imaging range is detected as the camera shake amount (B _X , B _Y ). Next, X, X
After shifting in the Y direction by the blur amounts B _X and _BY respectively,
The difference between the luminance Y and the current image is compared with the image before the predetermined time. Then, an area where the obtained difference is not zero is detected as a moving object.

When the area detected as a moving object is flesh color, it is determined as a person. In addition, the shape of the area is determined. When the area is substantially circular, it is detected as a face, and when it is elongated, it is detected as a hand or a foot.

In the above embodiment, the color cast is determined using the average color value of the pixel data for each block. Instead, a color histogram is created to determine the color cast. You may. In this case, the above equation
In (1) and (2), if Rave (n), Gave (n) and Bave (n) are frequencies of a predetermined gradation width centered on R, G and B data instead of the average value, Good.

In the above-described embodiment, the thinning rate of the image data is changed between the time of the shooting preparation state and the time of the shooting execution. However, instead of this, or in addition to this,
The resolution of the image data may be changed. For example, the A / D converter of the photographing unit 21 may convert the digital value into a 6-bit digital value when the photographing is ready, and convert the digital value into a 10-bit digital value when performing the photographing. In this embodiment, as in the above embodiment, high-speed processing can be performed in the shooting preparation state, and a high-quality image can be obtained when shooting is performed.

In the above embodiment, the detection of the skin color is
Converts image data based on R, G, B signals to hue H and corrected saturation
The image data is converted into image data based on Q, but is not limited to this. For example, the image data may be converted into values in the u ′, v ′ color space.
In this case, u '= (11.1 · R + 7.0 · G + 4.5 · B) / (17.8 · R + 70.8 · G + 18.8 · B) ... (16) v' = (9.0 · R + 41.3 · G + 0.54 (B) / (17.8.R + 70.8.G + 18.8.B) (17) converts image data based on the R, G, B signals into image data based on the u ', v' color space.

Then, the range of the flesh color is set to 0.225 ≦ u ′ ≦ 0.270 (18) 0.470 ≦ v ′ ≦ 0.505 (19), and it is determined whether or not the value of each pixel is within the range of the flesh color. What is necessary is just to detect.

The image data based on the u ′, v ′ color space is not affected by the change in luminance, so that the skin color can be detected appropriately.

Next, a printer which is an embodiment of the image output apparatus according to the present invention will be described. FIG. 18 is a perspective view showing the appearance of the printer, and FIG. 19 is a block diagram showing functional blocks of the printer.

In FIG. 18, a printer 40 is a self-type printer that prints out an image recorded by the digital still camera 1, and has external recording medium loading ports 42, 43, 44 at appropriate places in the apparatus main body 41. A discharge port 45 from which the recording paper is discharged and an operation display unit 46 are provided.

The external recording medium loading ports 42 to 44 are for loading a detachable external recording medium 47 (FIG. 19) used for a digital still camera. For example, the external recording medium loading port 42 has an EEPROM or the like. Card-type memory equipped with an external recording medium loading port 43
A card type memory of a different standard from the memory loaded in the external recording medium loading port 42 is loaded into the external recording medium loading port 42, and the FD is loaded into the external recording medium loading port 44. Therefore, the external memory 8 (FIG. 2) stores the external recording medium loading port 42.
What is necessary is just to load in the suitable loading port among -44.

The operation display section 46 has a touch panel laminated on a liquid crystal display section.
In addition to displaying images and the like recorded in memories loaded in the memory devices 2 to 44, an instruction to select an image to be printed out can be given.

In FIG. 19, a data fetching section 51 fetches data recorded on the external recording medium 47 loaded in the external recording medium loading ports 42 to 44, and sends the data to the image processing section 52. . Here, of the captured data, data representing an image is transmitted as color image data 51R, 51G, and 51B.

The image processing section 52 uses the image information data when the data fetched by the data fetching section 51 includes the image information data together with the image data representing the image as shown in FIG. And performs a correction process on the image data, and has the following functions:

The color image signal 51 is set so that the luminance of the position of the person indicated by the image information data becomes an appropriate value.
Function to correct output values of R, 51G, 51B.

Here, in the present embodiment, the appropriate value of the luminance means that, for example, when the digital value is represented by 8 bits (0 to 255), the average luminance Y of the partial area satisfies 100 ≦ Y ≦ 150. It is a thing.

The average luminance Y is equal to the color image signal 51.
Assuming that the respective values of R, 51G, and 51B are R, G, and B, they can be obtained by the above equation (15).

The color image signals 51R and 51R are set so that the color data at the position of the person indicated by the image information data falls within the appropriate range indicated by the above equations (13) and (14).
A function for performing a color balance correction process for correcting the ratio of G and 51B. As a result, the person's skin color is printed in an appropriate color.

The appropriate range may be set in advance and stored in the memory of the control unit 54. Instead of this, the user may be able to input settings by using the operation display unit 46.

As shown in Table 2 above, similarly to the image data correction unit 32 (FIG. 2) of the digital still camera 1,
The degree of enhancement of the edge enhancement processing is changed according to the shooting scene of the image information data. As a result, it is possible to print an image that has been subjected to appropriate contour correction according to the shooting scene.

A function in which a plurality of gamma correction curves are stored in advance in the memory of the control unit 54 in correspondence with a plurality of shooting scenes, and a gamma correction curve corresponding to the shooting scene included in the image information data is selected. Γ stored in the memory of the control unit 54
As the correction curve, a curve suitable for the reflectance characteristic determined by the printing method of the printing unit 53 and the ink used is created in advance.

The printing section 53 prints an image based on the image data corrected by the image processing section 52 on recording paper. The control unit 54 includes a memory and the like,
For example, the operation of each of the functional blocks 46, 51, 52, and 53 is controlled such that the image based on the image data corrected by the image processing unit 52 is printed on recording paper by the printing unit 53.

FIG. 20 is a flowchart showing the operation of the printer 40. In the figure, first, data is read from the external recording medium 47 loaded in the external recording medium loading ports 42 to 44 (# 600).

Next, the read data is expanded (# 605), and it is determined whether or not image data exists in the read data (# 610). If the image information data does not exist (NO in # 610), the image data is taken in (# 615), and the scene of the image is determined from the image data (# 620), and the scene of the determined image is determined. The image data is subjected to a correction process in response to (# 625), and the process proceeds to # 660.

If only the image data is used, it is difficult to determine the scene of the image. In order to avoid the risk of improper correction due to erroneous determination and consequently deteriorating the image quality, a large correction process is required. Not done. On the other hand, when image information data exists, it is possible to perform a high-performance correction process as described below.

That is, if image information data exists in # 610 (YES in # 610), information on the photographic scene is fetched (# 630). For example, evening scene,
In the case of night scenes, sea scenes, etc., as described in Table 2 above, appropriate corrections such as color balance and exposure value depending on the shooting scene, such as not performing standard corrections so as not to impair the characteristics of the image. Since the amounts are different, an appropriate correction is performed using this information in # 655 described later.

Next, information about the person, such as the presence or absence of the person, the number of people, and the position, is taken in (# 635). By capturing and effectively utilizing information about a person who is difficult to distinguish from image data alone,
At 55, the exposure value, the color balance, etc. are corrected to appropriate values for the person.

Next, information on correction processing such as color balance and γ correction is fetched (# 640). By taking in information on the correction processing performed by the digital still camera, the correction performed by the camera is not wasted and the correction that cannot be considered in practice is not performed in # 655 described below.

Next, the maximum correction amount is determined so as not to perform excessive correction (# 645). The maximum correction amount is determined, for example, as follows. When the values of the correction coefficients Δr and Δb recorded as the image information data are respectively Δr = 0.6 and Δb = 1.5, the maximum widths of the correction coefficients that can be generated by the color cast by the actual light source are 0.5 ≦ Δr ≦ Since 2.0 0.5 ≦ Δb ≦ 2.0, the range in which color correction can be performed during printing is 0.5 / 0.6 ≦ Δrp ≦ 2.0 / 0.6 0.5 / 1.5 ≦ Δbp ≦ 2.0 / 1.5 That is, 0.83 ≦ Δrp ≦ 3.33 0.33 ≦ Δbp ≦ 1.33 Becomes Here, Δrp is a red correction coefficient at the time of printing, Δ
bp is a blue correction coefficient at the time of printing.

As described above, the range that can be corrected during printing is determined as the maximum correction amount based on the correction information recorded as image information data and the maximum width determined by the characteristics.

Next, the raw image data is fetched (#
650), a correction process is performed on the image data (# 65)
5). This correction processing is performed by the information fetched in # 630 to # 640, the maximum correction amount determined in # 645, the printing unit 5
3 is performed based on data such as characteristics (for example, a color reproduction range, a reflectance characteristic, a γ correction curve, and a filter for edge enhancement) of the image forming apparatus 3. The data relating to the characteristics of the printer 40 is stored in the memory of the control unit 54.

Then, the image is printed based on the corrected image data (# 660), and the process ends.

As described above, according to the present embodiment, in particular,
By appropriately performing a correction process such as an exposure value or a color balance for a person having a predetermined size or more, it is possible to finish printing a very beautiful image.

[0184] Further, with respect to a photographic scene of only a landscape where no person exists, by using the information on the photographic scene, a correction process can be performed so that the image is more beautifully finished, and the color reproduction of the flesh color of the person is taken into consideration. It is possible to make corrections so that the landscape color becomes more vivid without performing.

In the above embodiment, the description has been made by applying the present invention to the self-type printer 40. However, the present invention is not limited to this.

For example, the block diagram shown in FIG. 19 may be modified from a personal computer having a data acquisition unit 51, an image processing unit 52, and a control unit 54, an operation display unit 46 having a keyboard, a mouse, and a CRT (or LCD), and a personal computer. Printing unit 5 consisting of a printer connected by a cable to
3 may be provided as a personal computer system 40.

According to this embodiment, it is possible to configure an image output device that prints out an image on a recording sheet by the printing unit 53, and furthermore, it is also possible to use the CR of the operation display unit 46.
An image output device that displays and outputs an image on a screen such as T can be configured.

As one embodiment of the image processing system according to the present invention, the digital still camera 1 shown in FIG.
And a printer (or personal computer system) 40 shown in FIG.

In this embodiment, on the camera 1 side, image information data composed of information relating to image determination of a photographic scene or a person and information relating to correction processing applied to image data is stored as recording data in association with the image data. Keep it. On the other hand, the printer 40 prints out an appropriate image by effectively utilizing the image information data stored in association with the image data. According to this embodiment, it is possible to realize an image processing system that can appropriately perform image capturing and output.

Here, image output using digital values will be described with reference to FIG. FIG. 21 is a diagram showing the concept of digital image output.

First, as shown in the lower right quadrant of FIG. 21, when a subject is imaged using, for example, a digital still camera, it is photoelectrically converted into a digital value 61 corresponding to the brightness of the subject.

On the other hand, in a general digital still camera, the tone reproduction curve 62 (desired image characteristics when displayed and output on the standard monitor, taking into account the reflectance characteristic M1 of the standard monitor (shown in the upper left quadrant of FIG. 21)) is used. As shown in the upper right quadrant of FIG. 21, the γ-LUT 63 (Look Up
A table, a correction curve, and a lower left quadrant in FIG. 21 are created in advance, and are stored in a memory or the like.

Therefore, the digital value 61 obtained by photoelectric conversion is obtained.
Is characteristic-converted by the γ-LUT 63.

When the digital value subjected to the characteristic conversion is observed on a standard monitor of the reflectance characteristic M1, since the γ-LUT is created in consideration of the reflectance characteristic M1,
An image is displayed and output with characteristics according to the tone reproduction curve 62.

As described above, in a digital still camera, generally, correction processing is performed on image data so that an appropriate image is obtained when observed on a standard monitor. Here, since the optimum tone reproduction curve differs depending on the shooting scene, a plurality of γ-LUTs
Is stored, and γ corresponding to the determined shooting scene is stored.
-LUT is selected.

On the other hand, when an image is printed out, reflectance characteristics and color reproduction characteristics are determined by a printing method such as an ink jet system, a fusion type thermal transfer system, a sublimation type thermal transfer system, and inks such as dyes and pigments. There is a high possibility that image output characteristics such as a color reproduction area are significantly different from those of a standard monitor. In the upper left quadrant of FIG. 21, as an example, a reflectance characteristic P1 of the ink jet system and a reflectance characteristic P2 of the sublimation thermal transfer system are shown, which are different from the reflectance characteristics M1 of the standard monitor.

Since a printer is required to output a beautiful image as a device for printing and outputting an image, the printer not only performs conversion for correcting the reflectance characteristic of the printer itself with respect to a standard monitor, but also performs conversion for each printer. Performs unique color conversion according to the model characteristics of.

At this time, in the image output apparatus according to the present invention, for example, as described with reference to FIG.
In step # 655, image data is subjected to a correction process using information about a person, information about a shooting scene, information about a correction, and the like, and an image is output based on the image data on which the correction process has been performed.

With this, each printer, CRT, LC
An image output appropriate for each characteristic such as D can be output.

[0200]

As described above, according to the first aspect of the present invention, in the shooting preparation state, the state relating to the subject is determined by using data obtained by performing predetermined processing on the image data output from the imaging means. On the other hand, when the second operation is performed on the operation unit to perform the photographing operation for image recording, the image data output from the imaging unit is subjected to a process different from the above-described predetermined process. Since the state relating to the subject is determined using the obtained data, a process capable of performing a high-speed determination is performed as a predetermined process in the shooting preparation state, while a predetermined process is performed in the shooting operation. By performing processing that can be determined with high precision as processing different from the processing, it is possible to make suitable determinations in the shooting preparation state and in the execution of the shooting operation, respectively. Kill.

According to the second aspect of the present invention, in the photographing preparation state, a process of extracting data decimated at a predetermined pitch from image data output from each photoelectric conversion element of the imaging means is performed as a predetermined process. On the other hand, when performing a shooting operation, as a process different from the above-described predetermined process, a process of extracting data thinned out at a pitch smaller than the predetermined pitch from the image data is performed, so that the shooting preparation state is set. In some cases, the determination can be made faster than when the shooting operation is performed. On the other hand, when the shooting operation is performed, the determination can be performed with higher accuracy than in the shooting preparation state. Suitable determination can be made for each time and when the shooting operation is performed.

According to the third aspect of the present invention, in the photographing preparation state, as a predetermined process, the imaging means is divided into m (m is an integer of 2 or more) blocks each including a plurality of photoelectric conversion elements. On the other hand, when performing the photographing operation while performing the processing, as a processing different from the above-described predetermined processing, the imaging unit is configured by a plurality of photoelectric conversion elements each of n (n is m <n).
Since the process of dividing the image into blocks is performed, it is possible to make a high-speed determination using image data of a smaller number of blocks as compared with the time of executing the shooting operation. At the time of execution, it is possible to determine with high accuracy using a larger number of image data for each block than at the time of the shooting preparation state. Suitable determination can be made.

According to the fourth aspect of the present invention, the first state determining means and the second state determining means each determine at least one of a photographing scene, a main subject position, and a person position as the state relating to the subject. Since it is determined that the photographing is ready, the photographing operation is executed and the photographing operation is executed.
At least one of the position of the main subject and the position of the person
One determination can be made.

According to the fifth aspect of the present invention, in the photographing preparation state, the first correction processing is performed on the image data output from the imaging means, while the second operation is performed on the operation means. When the photographing operation for recording the image is performed, the first
Since the second correction process different from the first correction process is performed, the first correction process can be performed at a high speed, and the second correction process can be performed with high accuracy. By performing the appropriate processing, it is possible to perform a suitable correction process for each of the time of the shooting preparation state and the time of executing the shooting operation.

According to the sixth aspect of the present invention, when executing the photographing operation, the image data output from the image pickup means is subjected to correction processing for a plurality of characteristics, while the image pickup apparatus is in a photographing preparation state. The image data output from the means is subjected to correction processing for only some of the plurality of characteristics, so that it is suitable for each of the photographing preparation state and the photographing operation execution. Correction processing can be performed for various characteristics.

According to the seventh aspect of the present invention, in the photographing preparation state, by subjecting the exposure value and the color balance characteristic to correction processing, the image of the subject can be displayed on the display means at a predetermined level of image quality. At the time of executing the photographing operation, an image can be recorded on the recording unit with high image quality by performing correction processing on at least a plurality of characteristics including an exposure value, a color balance characteristic, and a γ characteristic.

According to the invention of claim 8, when the correction amount for the image data is calculated based on the determination result by the first state determination means, when the calculated correction amount is equal to or more than a predetermined level, Since the first correction process is performed using the level as a correction amount, a weak correction process is performed, and an image of a subject close to a state captured by the imaging unit is displayed on the display unit. The person can better understand the tendency of the image of the subject.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of a digital still camera which is an embodiment of an image photographing apparatus according to the present invention.

FIG. 2 is a block diagram showing functional blocks of the digital still camera.

FIG. 3 is a diagram illustrating an arrangement state of CCDs in an imaging unit.

FIG. 4 is a diagram illustrating an arrangement state of CCDs in an imaging unit.

FIG. 5 is a diagram showing an example of block division.

FIG. 6 is a diagram showing an example of a color cast determination result.

FIG. 7 is a flowchart showing a main routine of the digital still camera.

FIG. 8 is a flowchart of a first imaging condition setting subroutine.

FIG. 9 is a flowchart of a first scene determination processing subroutine.

FIG. 10 is a flowchart of a first image data correction subroutine.

FIG. 11 is a flowchart of a second imaging condition setting subroutine.

FIG. 12 is a flowchart of a second scene determination processing subroutine.

FIG. 13 is a flowchart of a second image data correction subroutine.

FIGS. 14A to 14D are diagrams showing γ correction curves.

FIG. 15 is a diagram showing a filter used for edge enhancement processing, where (a) shows a filter having a high degree of edge enhancement;
(b) shows a filter with a medium edge enhancement degree,
(c) shows a filter having a weak edge enhancement degree.

FIG. 16 is a flowchart of an image information data setting subroutine.

FIG. 17 is a diagram illustrating an example of recording data.

FIG. 18 is a perspective view showing the appearance of a printer which is an embodiment of the image output device according to the present invention.

FIG. 19 is a block diagram showing functional blocks of the printer.

FIG. 20 is a flowchart illustrating an operation of the printer.

FIG. 21 is a diagram illustrating the concept of digital image output.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Digital still camera 4 Image display part 6 Shutter button (operation means) 8 External memory (recording means) 21 Image pickup part (image pickup means) 22 Image data temporary storage part 23 Image pickup control part 24 Image data processing part 25 Sequence control part (Operation Control means) 26 display control unit 27 recording control unit (recording control unit) 31 scene determination unit (first state determination unit, second state determination unit) 32 image data correction unit (image data correction unit, first image data correction unit) 33, image information setting unit 34, image data synthesizing unit 40 printer, personal computer system 42-44, external recording medium loading port 46, operation display unit (image output unit) 47, external recording medium (recording unit) 51 Data acquisition unit (image data acquisition unit) 52 Image processing unit (output image data correction unit) 3 printing unit (image output unit) 54 controller (output control means)

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI Theme coat ゛ (Reference) H04N 9/69 H04N 9/69 9/73 9/73 A // H04N 101: 00 101: 00 F term ( Reference) 2H054 AA01 5C022 AA13 AB00 AC01 AC03 AC42 AC69 5C065 AA03 BB01 BB12 BB19 BB48 CC01 DD02 GG13 GG44 HH02 5C066 AA01 CA17 EA13 EA14 EB01 EC01 EC02 EC05 KE05 KG01 KM02

Claims (8)

[Claims] 1. An image pickup device comprising: a plurality of photoelectric conversion elements arranged two-dimensionally; an image pickup means for picking up an image of a subject and outputting image data of the subject; an operation means operable from outside; and displaying an image. A display unit, for shifting to a photographing preparation state, which is a stage prior to photographing, according to a first operation on the operation unit, and for recording an image according to a second operation on the operation unit in the photographing preparation state. Operation control means for executing a shooting operation; first state determination means for determining a state relating to a subject using data obtained by performing predetermined processing on image data output from the imaging means in the shooting preparation state; When the second operation is performed on the operation means,
A second state determination unit that determines a state relating to a subject using data obtained by performing a process different from the predetermined process on image data output from the imaging unit; and a first state determination unit in the shooting preparation state. A first correction process is performed on the image data based on the determination result by the image data, and when the second operation is performed on the operation unit, the image data is processed based on the determination result by the second state determination unit. Image data correcting means for performing a second correction processing on the image data; display control means for displaying an image of a subject on the display means based on the image data on which the first correction processing has been performed in the shooting preparation state; Recording control means for recording, in a recording means, the image data subjected to the second correction processing when the photographing operation is performed. Imaging apparatus. 2. The image photographing apparatus according to claim 1, wherein the first state determining unit thins out the image data output from each of the photoelectric conversion elements of the imaging unit at a predetermined pitch as the predetermined processing. A process for extracting data is performed, and a state relating to the subject is determined using the extracted data. The second state determination unit performs the photoelectric conversion of the imaging unit as a process different from the predetermined process. An image photographing apparatus for performing a process of extracting data thinned out at a pitch smaller than the predetermined pitch from image data output from an element, and determining a state relating to a subject using the extracted data. . 3. The image photographing apparatus according to claim 1, wherein said first state determination means performs m (m) comprising a plurality of photoelectric conversion elements, respectively, as said predetermined processing.
Is an integer greater than or equal to 2) blocks.
The second state determination unit determines the state of the subject using the image data of each block. The second state determination unit performs a process different from the predetermined process by setting the imaging unit to a plurality of n (n An image photographing apparatus for performing a process of dividing the image into m (n <n) blocks and determining a state of a subject using image data of each block. 4. The image photographing apparatus according to claim 1, wherein said first state determination means and said second state determination means
An image photographing apparatus, characterized in that the state determining means determines at least one of a photographing scene, a position of a main subject, and a position of a person as the state relating to the subject. 5. An image pickup device comprising a plurality of photoelectric conversion elements arranged two-dimensionally, for picking up an image of a subject and outputting image data of the subject, operating means operable from outside, and displaying an image. A display unit, for shifting to a photographing preparation state, which is a stage prior to photographing, according to a first operation on the operation unit, and for recording an image according to a second operation on the operation unit in the photographing preparation state. Operation control means for executing a shooting operation; first state determination means for determining a state relating to a subject using image data output from the imaging means in the shooting preparation state; Is added,
A second state determination unit that determines a state relating to a subject using image data output from the imaging unit; and a first correction process that performs a first correction process on the image data based on a determination result by the first state determination unit. A first image data correction unit, a second image data correction unit for performing a second correction process different from the first correction process on the image data based on a determination result by the second state determination unit, A display control means for displaying an image of a subject on the display means based on the image data on which the first correction processing has been performed in the state, and the second correction processing on which the second correction processing has been performed when the photographing operation is performed. An image photographing apparatus comprising: a recording control unit that records image data in a recording unit. 6. The image photographing apparatus according to claim 5, wherein the second image data correction means performs correction processing on the image data for a plurality of characteristics, and wherein the first image data correction means comprises: An image photographing apparatus characterized in that correction processing is performed on only some of the plurality of characteristics. 7. The image photographing apparatus according to claim 6, wherein said second image data correction means includes at least an exposure value, a color balance characteristic and a γ characteristic as said plurality of characteristics. An image photographing apparatus, wherein the correction means performs a correction process on an exposure value and a color balance characteristic among the plurality of characteristics. 8. The image photographing apparatus according to claim 6, wherein the first image data correction means calculates a correction amount for the image data based on a determination result by the first state determination means. When the calculated correction amount is equal to or higher than a predetermined level, the first correction process is performed using the predetermined level as a correction amount.