JP2003244621A - Image processing method and image processing apparatus, control program for the image processing apparatus, and storage medium - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image processing method and an image processing apparatus, a control program for the image processing apparatus, and a storage medium capable of enhancing detection accuracy and sophisticating corrected contents. <P>SOLUTION: A PC 103 controls correction of image of image data by using the color temperature information of a flash light source. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image processing method for processing an image file created by a photographing input device such as a digital camera, an image processing apparatus, a control program for the image processing apparatus, and a storage storing the control program. Regarding the medium.

[0002]

2. Description of the Related Art In recent years, with the spread of digital cameras,
Digitization of photographic images has become easy. In particular, PCs (personal computers) have increased the opportunity to handle photographic images as digital data, and applications have come to process and edit image files.

Further, the performance of an ink jet printer, which is widely used as a printing device connected to a PC, has the output performance equivalent to that of a silver salt photograph, and it is changed to a silver salt photograph and photographed by a digital camera or the like. The environment and demand for printing image files on inkjet printers are in place.

Further, in the silver salt photography, as a method of printing on a photographic printing paper, a device is devised so as to produce a preferable color for a target image which can be noticed in the image.

On the side of a photographing input device such as a digital camera, the following various proposals have been made so that an image can be photographed without using this method.

That is, the color temperature of the light source of the flash varies from manufacturer to manufacturer, and the variation is ± 1 in ΔE.
It is about 0.

[0007] On the other hand, some manufacturers have been devised to suppress the influence by correcting the recording amplifier when shooting with a flash.

[0008] As an example thereof, Japanese Patent Laid-Open No. 2001-5649
No. 4 proposes a flash device that transmits the intrinsic color temperature of its own flash as color temperature information to the input device side for photographing via a communication line.

Further, in Japanese Patent Laid-Open No. 2001-136546, when the color temperature information of the flash is detected from the focus detection area and the skin color of the object is detected from this color temperature information,
An electronic camera has been proposed which has a gain calculation means for calculating a gain using the detected skin color.

Further, in Japanese Patent Laid-Open No. 2001-230970, a proposal of an image pickup apparatus for selecting a shooting condition according to a distance rank of a subject, a read mode, and an exposure rank set by a user if necessary. Has been done.

[0011]

[Problems to be Solved by the Invention]
The market does not consist of a light source management that allows the subject to be captured well when shooting, and whether or not the subject is a person, and if it is a person, the digital camera that selects the exposure centered on that person is forming the market. Most of them do not satisfy this function, and the correction is completed at the time of shooting.

Further, in these conventional examples, all of them are corrected at the time of photographing, and no means is taken after the photographed image is made into a file. This is believed to be the difference between the silver salt photographic print output and the output of digital cameras and inkjet printers.

In order to fill this output difference, generally, the captured image files are individually corrected,
It is to take measures to optimize the output.

In the case of performing image analysis of an image file to be processed obtained by photographing with a digital camera and performing automatic image correction of the target image file based on the analysis result, basically all target images are processed. Automatic image correction will be performed with standard correction that is theoretically considered optimal for the file. In many cases, color correction and brightness correction by this method statistically perform image processing using image histograms, and it is not always possible to optimally correct all images by only analyzing image data.

Further, in an image using a flash as a light source for illumination, the color temperature and the light amount of the light source may affect the accuracy of image recognition for image correction.

As one means of image correction, in the chromaticity detection means which is one of means for detecting the image of interest from the taken image file, in the case of flash photography, the appropriate chromaticity is affected by the color temperature. It was difficult to judge.

Further, the light emission amount of the flash is adjusted so that an image of optimum brightness can be obtained when the distance from the subject to the digital camera is within a certain range. Does not always have a good relationship between the subject and the light amount of the flash.

The present invention has been made to solve the above-mentioned problems of the prior art, and an object thereof is an image processing method and an image processing capable of improving detection accuracy and sophistication of correction contents. An object of the present invention is to provide a control program and a storage medium for an apparatus and an image processing apparatus.

[0019]

In order to achieve the above object, the image processing method according to the present invention uses, as image-related data in addition to image data, ON / OFF information indicating whether or not the image is at least a flash image. And a color temperature information of the light source of the flash, and an image processing method for processing a photographed image file created by a photographing input device, the color temperature information of the light source of the flash is used to convert the image data into the image data. It is characterized by having a control step for controlling to perform an image correction process.

In order to achieve the above object, the image processing apparatus of the present invention has, as image-related data in addition to image data, at least ON / OFF information indicating whether or not the image was taken by flash and the flash. In an image processing device for processing a captured image file in which the color temperature information of the light source is described and created by an input device for imaging, an image correction process is performed on the image data by using the color temperature information of the light source of the flash. It is characterized by having control means for controlling so as to perform.

In order to achieve the above object, the image processing method of the present invention has, as image-related data, image-related data, at least ON / OFF information indicating whether or not the image has been flash-photographed, and the flash. An image processing method for processing a photographed image file, which describes color temperature information of a light source and which is created by a photographing input device, in the color image information of the image data using the color temperature information of the light source of the flash. It is characterized by having a control step for controlling so as to perform.

In order to achieve the above object, the image processing apparatus of the present invention has, as image-related data in addition to image data, at least ON / OFF information indicating whether or not the image was taken by flash and the flash data. An image processing apparatus for processing a captured image file in which color temperature information of a light source is described and which is created by an input device for imaging, in which an image of interest in the image data is detected using the color temperature information of the light source of the flash. It is characterized by having a control means for controlling so as to perform.

Further, in order to achieve the above object, the image processing method of the present invention has, in addition to image data, shooting-related data, at least ON / OFF information indicating whether or not the image is taken by flash, and the flash data. In an image processing method for processing a photographed image file in which effective light amount reaching distance information and photographing focal distance information are described and which is created by a photographing input device, an image correction process for the image data by using the photographing related data It is characterized by having a control step for controlling so as to perform.

In order to achieve the above object, the image processing apparatus of the present invention has, as image-related data in addition to image data, at least ON / OFF information indicating whether or not the image was taken by flash and the flash data. In an image processing apparatus for processing a photographed image file in which effective light amount reaching distance information and photographing focal length information are described and which is created by a photographing input device, image correction processing for the image data using the photographing related data It is characterized by having a control means for controlling so as to perform.

In order to achieve the above object, the control program of the image processing apparatus of the present invention includes, in addition to image data, shooting-related data, at least ON / OFF information indicating whether or not the image is a flash-shot image. In a computer-readable control program for controlling an image processing device for processing a captured image file created by a capturing input device, which describes color temperature information of the flash light source, a color temperature of the flash light source It is characterized by comprising a program code for causing a computer to execute a control step for controlling to perform an image correction process on the image data using information.

Further, in order to achieve the above object, the control program of the image processing apparatus of the present invention has, as image-related data, ON / OFF information indicating at least whether or not the image is a flash image. In a computer-readable control program for controlling an image processing device for processing a captured image file created by a capturing input device, which describes color temperature information of the flash light source, a color temperature of the flash light source It is characterized by comprising a program code for causing a computer to execute a control step of controlling to perform a target image detecting process in the image data by using information.

In order to achieve the above object, the control program of the image processing apparatus of the present invention includes, in addition to image data, ON / OFF information indicating whether or not the image is at least a flash image as shooting-related data. In the computer-readable control program for controlling the image processing apparatus for processing the captured image file created by the capturing input device, in which the effective light amount reaching distance information of the flash and the capturing focal length information are described, It is characterized by comprising a program code for causing a computer to execute a control step for controlling to perform an image correction process on the image data by using related data.

Further, in order to achieve the above object, the storage medium of the present invention is characterized by storing a control program for the image processing apparatus.

[0029]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below with reference to the drawings.

(First Embodiment) First, a first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 is a block diagram showing the schematic arrangement of an image processing system having an image processing apparatus according to this embodiment.

In FIG. 1, reference numeral 101 denotes an input device (photographing input device) such as a digital camera. An image file 102 photographed by the input device 101 has photographed image data 102a as photographed image file data.
In addition, shooting-related data 102b related to shooting data such as shooting conditions, camera information, shooting intention, and print commands are described.

In particular, in the present embodiment, the flash ON / O at the time of shooting is used as the shooting-related data 102b.
The FF information and the color temperature information of the flash are indispensable, and further, effective light amount reaching distance information of the flash at the time of shooting, focal length information, and the like are described. This shooting related data 10
Details of 2b will be described later.

The photographed image file data is usually a memory card in the input device 101 (compact flash (registered trademark), smart media, memory stick, SD card, etc. are commercialized and distributed).
It is recorded and stored in.

As a method of transferring the photographed image file data (the photographed image data 102a and the photographing related data 102b) described in the image file 102 to the image correction processing apparatus and the printing apparatus (printer), a memory card in the input device 101 is used. Is removed from the input device 101,
When directly connecting to the slot of the image correction processing device and the printing device, or when using a USB (Universal Serial)
Bus), IEEE1394, serial, etc. for data transfer via cable connection, IrDA (Infrared)
In some cases, infrared communication such as Data Association) is used.

Next, regarding the image correction processing device and the printing device side, there is a connection environment between the PC (personal computer) 103 surrounded by the alternate long and short dash line in FIG. 1 and a printer which is a printing device described later.

The PC 103 uses the captured image file 1
02 is decompressed and expanded by an application, and based on the captured image data 102a, the captured image data 10
An image processing device (image processing apparatus) 103a that analyzes whether or not 2a is good captured image data and performs image correction processing as necessary, and a print data generation unit that generates print data according to a subsequent print command. And 103b,
The print data generated by the print data generation unit 103b is output to the printer described later.

Further, a PD (Photo Direct) machine or the like, which partially incorporates the processing function of the PC 103, is provided inside the printer 104, which is a printing apparatus surrounded by a dotted line in FIG.
Similar to the PC 103, it exists as an environment for receiving the captured image file data described in the image file 102 and executing print output. The printer 104 has a printer body 104a for printing out print data and a display device 104b for displaying print data and the like.

A feature of this embodiment is that the quality of the image file 102 is improved by effectively using it for the data analysis process and the image correction process based on the photographing-related data 102b in the image file 102. .

Here, as the recording method of the input device 101, the "Exif" file format which is a typical image file format generally used in the market will be described.

FIG. 2 is a diagram showing the structure of the Exif file.

The structure of the Exif image is basically a normal JPEG image format itself, in which data such as thumbnail images and shooting-related data are embedded in a form conforming to the JPEG standard. An Exif image file can be viewed as a normal JPEG image by using an Internet browser, image viewer, photo retouching software, etc. that support the format.

As shown in the left side portion of FIG. 2, the JPEG file is initially SOI (Start of image).
e / 0xFFD8) 201a, then APP1
201b is followed by DQT (Define Quan).
Tization Table) 201c, followed by DHT (Define Huffman Table)
201d, then SOF201e, then SO
S (Start Of Frame) marker 201f
However, there is compressed data (data) 201g next, and then EOI 201h.

Markers used in JPEG (Make
Among r), markers from 0xFFE0 to 0xFFEF are called application markers, and these are
Although it is not necessary for decoding the JPEG image, it is defined as a data area used by each application program. In Exif, a marker called APP1 (0xFFE1) is used to store the captured image data 102a and the like in a JPEG image. The structure of "APP1" is shown in FIG.
It is the right part of.

That is, in the structure of "APP1", first, there is an APP1Maker (FFE1 / 2 byte) area 202a at the head, and then APP1Length (2b).
yte APP1 area size) area 202b,
Next is the data area 202c of APP1. This A
The first 6 bytes of data following the data area 202c of PP1 are ASCII characters "Exif" as an identifier.
, Followed by 2 bytes of 0x00. From there Ti
Data is stored in ff format.

The first 8 bytes of the Tiff format are Tiff
It becomes a header area 202d, and the first 2 bytes define a byte arrangement format. 0x4d
4d: Motorola format for "MM", 0x494
9: "II" indicates the Intel format.

Next 0t of the Tiff header area 202d
h In the IFD (IFD of main image) area 202e, the first IFD (Image file)
directory) is stored.

Usually, the main image data and the image-related data are contained in this, and the main information and the sub information (Exif SubIFD / 0x8) are included for each description item.
769), manufacturer-specific information (Maker note)
/ 0x927c) and the description items are separated.

FIG. 3 is a diagram showing an example of the "tag" address indicating the description content and description of the main information. As shown in the figure, the main information includes general information such as a title, a maker name or model name of the input device 101, an image orientation, a width resolution, a height resolution, a resolution unit, software, and a modification date and time. ing.

FIG. 4 is a diagram showing an example of the "tag" address indicating the description content and description of the sub information. As shown in the figure, as the sub information, detailed information of the input device 101 such as a light source and a lens focal length, an exposure time F value, and IS
Various shooting conditions such as O sensitivity and automatic exposure metering mode are described.

FIG. 5 is a diagram showing a description example of manufacturer-dependent data. The contents of the manufacturer's unique data, the "tag" address, etc. can be uniquely set for each manufacturer, so the details are unknown. Imaging-related data that is not defined in the sub information tends to be described.

Shooting-related data 1 in the present embodiment
02b is described in the "APP1" area 201b. The flash ON / OFF information is described in the sub information “tag = 0x9209” in FIG. 4, but the information such as the color temperature of the flash is described in the sub information in FIG. 4 or the manufacturer-specific data in FIG. It

Returning to FIG. 2, the description will be continued.

DQT (Defi) in the left part of FIG.
ne Quantization Table) 201c
Represents the actual state of the quantization table as DHT (Define H
uffman Table) 201d defines the actual condition of the Huffman table, and SOF (Star).
t Of Frame) 201e indicates the start of a frame, SOS (Start of stream) marker 201f indicates the start of image data, and EOI (End o).
f image / 0xFFD9) 201h indicates the end of the image.

Next, the color temperature of the light source when a flash is used in photographing with the digital camera which is the input device 101 will be described.

There is a color temperature as an index representing the color of the light source, and a normal light source that is substantially along the line of the black body radiation locus is used.

FIG. 6 is a color temperature characteristic diagram showing the color temperature of illumination light which is frequently used on the xy chromaticity diagram. As shown in the figure, the incandescent lamp is 2856K, the standard observation light of the printed photograph is 5000K, and the daylight and HDTV (sRGB) white are 65K.
00K, blue sky 7500K, Japanese TV white 930
It becomes 0K, and it is found that it is along the line of the black body radiation locus.

The light source color of the flash of the digital camera, which is the input device 101 for photographing, uses a fairly high color temperature, and the blue color becomes stronger, but the value varies depending on each maker, and the black body radiation locus. Some are out of
Not only the color temperature but also X
It may be represented by chromaticity such as YZ and L * a * b *.

FIG. 7 is a diagram showing an expression difference based on photographed image data obtained by flash photographing an achromatic gray chart with a digital camera which is a photographing input device of each manufacturer.

From FIG. 7, it can be seen that the color difference 1 in the blue / green direction is 1
It means that they are separated by 0 or more. Normally, in flash photography, it may be possible to adjust the gain of the amplifier in order to reduce the influence of the color temperature of the mounted flash, but this actually exists as variations in the captured image data.

Items to be performed in the normal image correction processing are as follows. 1) White balance correction 2) Contrast correction 3) Exposure correction 4) Saturation enhancement 5) Gradation correction 6) Target image correction Particularly, white balance correction and contrast correction are the most important items.

Here, regarding the white balance correction,
This will be described with reference to FIG.

FIG. 8 is a flowchart showing the flow of the white balance correction processing operation in the image processing device 103a which is the image processing apparatus according to this embodiment.

First, in step S801, highlight and shadow calculation processing is performed.

In this highlight and shadow calculation processing, the highlight / shadow points (LH
/ LS), red white / black balance (RH / R)
S), green white / black balance (GH / G
S), blue white / black balance (BH / B
S), corrected highlight / shadow point (HP /
SP) and highlight / shadow areas are set as parameters. Each value is handled by 8-bit 0-255.

In the initial state of white balance correction, each of these parameters is initialized with appropriate values.
For example, “245” is set as the corrected highlight point (HP) and “10” is set as the corrected shadow point (SP).

The highlight area is 99 to 100%, and the shadow area is 0 to 1%.

Each pixel of the photographed image data 102a in the image file 102 is read in and a luminance histogram is created. An example of this brightness histogram is shown in FIG.

The highlight point (LH) of the image is calculated based on the created luminance histogram. Where L
H is the minimum brightness in the highlight area of the image.

Therefore, in the brightness histogram shown in FIG. 9, the brightness range corresponding to the highlight area 99 to 100% is 230 to 255, so that LH is "230".
Is.

Further, the shadow point (LS) of the image is calculated based on the created luminance histogram. Here, LS is the maximum brightness in the shadow area of the image.

Therefore, in the luminance histogram shown in FIG. 9, the luminance range corresponding to 0 to 1% of the shadow area is 0 to 14, so that LS is "14".

Returning to FIG. 8 again, the next step S802.
Then, the white balance and the black balance are calculated.

In the calculation processing of the white balance and the black balance, first, the photographed image data 102a in the image file 102 is read pixel by pixel, and the brightness is L.
R, G, B of pixels in a region that is H or more and HP or less
Calculate the average brightness for each.

In the luminance histogram shown in FIG. 9, a region having a luminance of "230" or more and "245" or less is a target. Then, each of the obtained average values is R
H, GH, BH.

Next, the photographed image data 102a in the image file 102 is read pixel by pixel, and the average luminance for each R, G, B of the pixels in the region where the luminance is SP or more and LS or less is calculated. In the luminance histogram shown in FIG. 9, the region having the luminance of “10” or more and “14” or less is targeted. Then, each of the obtained average values is R
S, GS, BS.

Next, in step S803, the process (A) is executed.

FIG. 10 is a flow chart showing the operation flow of the process (A) executed in step S803 of FIG.

First, in step S1001, the shooting-related data 102b in the image file 102 is searched, and it is determined whether or not the image has been shot (flash shot) using a flash (Flash on). Then, if the image is not a flash image, step S1
After proceeding to 005 to return to the normal processing, the processing returns to the processing of FIG. If the image is captured by flash in step S1002, the next step S10
In step 02, it is confirmed whether or not the color temperature information of the flash is written in the shooting-related data 102b in the image file 102. If the color temperature information of the flash is not written, the step S10 is performed.
In step 05, the normal auto white balance process is executed, and then the process returns to the process shown in FIG. In addition, the step S1
When the color temperature information of the flash is written in 002, the process proceeds to the next step S1003, the white balance correction process using the color temperature information is performed, and then the process proceeds to the next step S1004.

The description unit of the color temperature information of the flash is basically indicated by the absolute temperature (K). Although this is also assumed in the present embodiment, some inexpensive light sources deviate from the black body radiation locus, and in that case, L * a * b *.
It is also possible to use chromaticity notation such as or XYZ, and it is also possible to envisage a tag in which an error due to the variation of the light source can be entered.

The flow chart of FIG. 10 will be returned to for further explanation.

In step 1003, a difference (hue difference) between the calculated white balance hue and the hue of the flash color temperature is calculated.

First, in order to obtain the hue of the white balance, the RGB data calculated as the white balance is subjected to XYZ conversion by the following formula.

[0084]

[Equation 1]

The calculated XYZ is calculated as L * a using the following formula.
Convert to * b *.

[0086]

[Equation 2]

Next, the color temperature of the flash is subjected to L * a * b * conversion after obtaining XYZ values from the chromaticity diagram of FIG.

The characteristic between two values of L * a * b * can be calculated by the following formula.

[0089]

[Equation 3]

In the present embodiment, the hue difference (Δ
H) is calculated.

Next, in step S1004, it is determined whether the value of the hue difference (ΔH) between the two points is larger than a preset threshold value. It is determined whether the white balance shift is due to the influence of the color temperature of the flash. If the result of the determination is smaller than the threshold value, it is determined that there is no influence of the flash, and the step S10 is performed.
After proceeding to 05, the normal auto white balance process is executed, and then the process returns to the process of FIG.

In the normal auto white balance processing executed in step S1005, the basic idea is that all the images become normal, so 100% correction process is not executed, usually 60-70%
It is common to perform a degree of correction processing.

On the other hand, if it is larger than the threshold value, it can be clearly recognized that the cause of the white balance shift is the light source of the flash, and it is not necessary to suppress the degree of white balance processing. Therefore, the procedure advances to step S1006. After changing the white balance processing intensity to 90% to 100%, the process returns to the process of FIG.

In the setting change processing of step S1006, the white balance processing intensity is set to have a range of 90 to 100%, although not shown in the flowchart of FIG. 10, the value of the hue difference (ΔH) is The reason is that the value within the threshold value is set to 100% when the accuracy is higher. This can be easily done by table or by a formula.

Returning to the flowchart of FIG. 8, the description will be continued.

After the processing of step S803 is completed, the process proceeds to the next step S804, the white balance and black balance correction processing is executed, and then the lookup table (LUT) is created based on the parameters.

An example of this LUT is shown in FIG. Figure 11
In the LUT shown in (1), highlight gamma is set in the order of G, B, and R. In this way, by strengthening G and B with respect to R, for example, a bluish color cast of an image can be corrected.

Next, in step S805, the image data is corrected pixel by pixel based on the LUT shown in FIG. 11 created in step S804, and this processing operation is terminated.

In this embodiment, the example in which the photographing-related data 102b is described in the "Exif" file structure has been described, but the description may be described inside the normal marker of APP1 or the manufacturer. It may be described in a note, and may not be the image file 102 in the “Exif” format.

Further, it goes without saying that the data of the format in which the shooting-related data 102a is described in the other area of the shot image data 102a in the image file 102 is targeted.

(Second Embodiment) Next, a second embodiment of the present invention will be described with reference to FIGS.

Since the schematic configuration of the image processing system having the image processing apparatus according to this embodiment is the same as that of FIG. 1 in the above-described first embodiment, the same drawing will be used for the description.

In the first embodiment described above, the color temperature correction means for white balance correction in a flash photographed image has been described, but in the present embodiment, under the same environment as this, as a more advanced use example, A usage pattern in the case of detecting a target image in a captured image and executing image correction focusing on the target image will be described.

Specifically, the case is searched for whether or not there is human skin that can be a target image in the image file 102. Normally, the detection method is a comprehensive judgment involving chromaticity information. Although it is general to detect human skin, this method cannot detect the human skin because the chromaticity detection area of human skin is displaced due to the influence of the color temperature of the flash.

In this embodiment, before performing the image correction processing shown in FIG. 8 in the above-described first embodiment, it is detected whether or not there is human skin which is the center of the correction processing. As a method of determining the chromaticity range for that, the process of the flowchart shown in FIG. 12 is executed.

First, in step S1201, in the image file 102, ON / OFF information as to whether or not the image is a flash-photographed image and color temperature information of the flash as image-related data 102b in addition to the photographed image data 102a. Determine whether there is a description. And image file 1
In 02, in addition to the photographed image data 102a, ON / OFF information indicating whether or not the image is flash photographed, and color temperature information of the flash are described as photographing-related data 102b. Processing of step S1202 and subsequent steps is performed, otherwise,
The process returns to the normal human flesh color detection process in the normal chromaticity setting range without any processing.

In step S1202, the hue and hue angle are calculated from the color temperature of the flash (converted to L * a * b *), and in the next step S1203, the hue difference between the flash color temperature and the reference value, That is, the hue difference (S) between the hue of the reference white (reference white in sRGB in the present embodiment) and the same luminance data that matches is calculated.

Next, in step S1204, it is determined whether to shift the chromaticity range in the human skin color detection in the color temperature direction of the flash based on the magnitude of the hue difference (S) calculated in step S1203. The shifted chromaticity direction is determined by the hue difference between the hue obtained from the color temperature of the flash and the reference light.

Next, in step S1205, after the deviation correction amount to the human skin detection chromaticity range is set, human skin detection is performed using the changed chromaticity range, and image correction processing reflecting the result is performed. Transition.

FIG. 13 shows an example of the chromaticity range when the flash color temperature is detected and the human skin color detection chromaticity range is moved in the digital single lens reflex camera 100 which is the image processing apparatus according to this embodiment. In the figure, the horizontal axis represents the red component ratio (R / R + G + B), and the vertical axis represents the green component ratio (G / R + G + B).

As shown in FIG. 13, since the color temperature of the flash light source is as high as 8000 ° K with respect to the chromaticity range (solid line) of the reference light with the sRGB environment as the reference, it is shifted to the bluish range from the reference value. It can be seen that the human skin color detection chromaticity range has moved to the area indicated by the broken line.

In the present embodiment, the chromaticity range of the human flesh color to be detected is detected in the range shifted in the calculated color temperature direction of the flash, but there is a possibility that a subject to which the flash light does not reach may be included. Therefore, the chromaticity detection range may be expanded by the amount corresponding to the color temperature direction of the flash.

In the present embodiment, the chromaticity detection value of the human flesh color is shown, but it is needless to say that the detection can be applied even if the detection target is not the human flesh color. . For example, a sky blue color, a forest green color, or the like that can be set by chromaticity can be a target of the present invention.

(Third Embodiment) Next, a third embodiment of the present invention will be described with reference to FIG.

Since the schematic configuration of the image processing system having the image processing apparatus according to this embodiment is the same as that of FIG. 1 in the above-described first embodiment, the same drawing will be used for the description.

In the present embodiment, the exposure correction process is performed by executing the process of the flowchart shown in FIG. 14 before performing the image correction process of the flowchart shown in FIG. 8 in the above-described first embodiment. This is to enable effective information to be obtained.

Specifically, in FIG. 14, first, whether or not the following information (1) to (5) is described in the image file 102 as the photographing related data 102b in addition to the photographed image data 102a. To detect. (1) Flash ON / OFF information (2) Flash effective light amount reaching distance information (3) Shooting focal length information (4) Flash light source color temperature information (5) Exposure value information at the time of shooting where (1) above The information items (3) to (3) are essential items in the present embodiment.

Next, in step S1402, it is determined whether or not the image is a flash-used image. Then, if the flash is the used image, the next step S
Proceeding to 1403, and when the image is not the image in which the flash is used, this processing operation is ended and the processing shifts to normal processing.

In step S1403, the absolute value (| Z |) is calculated by subtracting the effective reach distance of the flash from the photographing focal length.

Next, in step S1404, it is determined whether the absolute value (| Z |) calculated in step S1403 is larger than the threshold value. Then, the absolute value (| Z
If | is not a value larger than the threshold value, this processing operation is terminated and the processing shifts to normal processing.

When the absolute value (| Z |) is a value larger than the threshold value (1 meter in this embodiment),
The image is recognized as an image for which an appropriate exposure setting has not been made for the subject to be photographed, and the process advances to step S1405.

In step S1405, if the focal length is longer than the effective range of the flash, it is highly likely that the light quantity of the subject is insufficient. Therefore, the exposure value is set to be higher, and the effective range of the flash is shorter than the effective range. When the focal length is short, there is a high possibility that the amount of light of the subject is too large, so the exposure value is set to be low.

Next, proceeding to step S1406, after passing the constant set (determined) at step S1405 to the image correction application, this processing operation is ended and processing shifts to normal processing.

The application which has received the constants can execute the image correction specialized for the image file information in addition to the normal correction constants.

(Other Embodiments) The object of the present invention is to supply a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or apparatus, and to supply the system or apparatus. Needless to say, the above can also be achieved by the computer (or CPU, MPU, etc.) of which reads out and executes the program code stored in the storage medium.

In this case, the program code itself read from the storage medium realizes the functions of the above-described embodiments, and the storage medium storing the program code constitutes the present invention.

A storage medium for supplying the program code is, for example, a floppy (registered trademark) disk, a hard disk, a magneto-optical disk, or a CD-RO.
M, CD-R, CD-RW, DVD-ROM, DVD-
RAM, DVD-RW, DVD + RW, magnetic tape, non-volatile memory card, ROM, etc. can be used.

Further, not only the functions of the above-described respective embodiments are realized by executing the program code read by the computer, but also the OS (operating system) running on the computer based on the instruction of the program code. It goes without saying that this also includes the case where the system) performs a part or all of the actual processing and the processing realizes the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written in the memory provided in the function expansion board inserted into the computer or the function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that a case where the CPU or the like included in the function expansion board or the function expansion unit performs some or all of the actual processing and the processing realizes the functions of the above-described embodiments is also included.

[0130]

As described in detail above, according to the present invention, the image file has image-related data in addition to the image data, and the characteristic data related to the image correction is extracted from the image-related data to obtain the image. High-quality image correction specialized for each file can be realized.

Further, according to the present invention, in an image using a flash, a method using the color temperature information of the light source of the flash can enhance image correction processing such as image extraction, white balance and exposure correction. it can.

[Brief description of drawings]

FIG. 1 is a block diagram showing a system configuration having an image processing apparatus according to a first embodiment of the present invention.

FIG. 2 is a diagram showing a file structure of a compressed image file format “Exif” in the image processing apparatus according to the first embodiment of the present invention.

FIG. 3 is a diagram showing an example of main information in the image processing apparatus according to the first embodiment of the present invention.

FIG. 4 is a diagram showing an example of sub information in the image processing apparatus according to the first embodiment of the present invention.

FIG. 5 is a diagram showing an example of maker unique information items of an Exif file which is a compressed image file format in the image processing apparatus according to the first embodiment of the present invention.

FIG. 6 is a diagram showing a chromaticity range used for a skin color detection process and a chromaticity range using a flash color temperature in the image processing apparatus according to the first embodiment of the present invention.

FIG. 7 is a diagram showing color reproduction results for gray color chips by digital cameras of respective companies, which is reference data of the present invention.

FIG. 8 is a flowchart showing a flow of white balance adjustment processing operation in the image processing apparatus according to the first embodiment of the present invention.

FIG. 9 is a diagram showing an example of a histogram of image data for explaining WB correction in the image processing apparatus according to the first embodiment of the present invention.

FIG. 10 is a flowchart showing the operation flow of white balance adjustment processing (A) in the image processing apparatus according to the first embodiment of the present invention.

FIG. 11 is a diagram showing an example of a WB correction LUT in the image processing apparatus according to the first embodiment of the present invention.

FIG. 12 is a flow chart showing a flow of processing operations in which the chromaticity range for human skin detection in the image processing apparatus according to the second embodiment of the present invention corresponds to the color temperature of the flash.

FIG. 13 is a diagram showing a chromaticity range used for skin color detection and a chromaticity range when a color temperature of a flash is used in the image processing apparatus according to the second embodiment of the present invention.

FIG. 14 is a flowchart showing a system configuration having an image processing device according to a third embodiment of the present invention.

[Explanation of symbols]

Reference numeral 101 input device for capturing (input device: digital camera) 102 image file 102a captured image data 102b capturing related data 103 PC (personal computer) 103a image processing device (image processing device) 103b print data generation unit 104 printer 104a printer body 104b display Bowl 104b

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 9/04 H04N 1/40 D 5C077 9/73 1/46 A 5C079 5/91 Z H (72) Invention Person Yuji Akiyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Manabu Yamazoe 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Ryosuke Iguchi Tokyo 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Takashi Fujita 3-30-2 Shimomaruko, Ota-ku, Tokyo Incorporated (72) Canon Inc. Naohisa Suzuki Shimomaruko, Ota-ku, Tokyo 3-30-2 Canon Inc. F-term (reference) 5B057 BA02 CA01 CA08 CA12 CA16 CB01 CB08 CB12 CB16 CC01 CE17 CE18 CH08 5C022 AA13 AC69 5C053 FA04 FA07 FA 27 GB36 JA30 KA01 KA24 LA02 LA03 LA11 5C065 AA03 BB02 BB41 DD02 FF05 GG27 5C066 AA01 EA14 EC01 KL02 KM02 5C077 LL19 MP08 PP32 PP36 PP37 PP72 PQ12 TT09 5C079 HB01 HB05 HB11 JA25 LA03 LB01

Claims (28)

[Claims] 1. In addition to image data, at least ON / OFF information indicating whether or not an image is taken by flash and color temperature information of a light source of the flash are described as shooting-related data and created by an input device for shooting. In the image processing method for processing the captured image file, the image processing is characterized by including a control step for performing an image correction process on the image data by using color temperature information of a light source of the flash. Method. 2. The image correction process is a white balance correction process using a white balance constant detected in an analysis process of the image data and color temperature information of a light source of the flash. The image processing method described in. 3. The image processing method according to claim 1, wherein the captured image file is in a JPEG format. 4. In addition to image data, as photographing-related data, at least ON / OFF information indicating whether or not the image was taken by flash and color temperature information of a light source of the flash are described and created by an input device for shooting. An image processing apparatus for processing the captured image file is characterized by including control means for controlling to perform image correction on the image data by using color temperature information of the light source of the flash. . 5. The image correction process is a white balance correction process using a white balance constant detected in an analysis process of the image data and color temperature information of a light source of the flash. The image processing device according to item 1. 6. The image processing apparatus according to claim 4, wherein the captured image file is in JPEG format. 7. In addition to image data, at least ON / OFF information indicating whether or not the image was taken by flash and color temperature information of the light source of the flash are described as shooting-related data and created by an input device for shooting. In the image processing method for processing the captured image file, the image having a control step of performing a target image detection process in the image data by using color temperature information of a light source of the flash. Processing method. 8. The image processing method according to claim 7, wherein the target image detection process is performed using at least information based on the chromaticity range of the light source of the flash. 9. The image processing method according to claim 7, wherein the captured image file is in the JPEG format. 10. In addition to image data, at least ON / OFF information indicating whether or not the image is taken by flash and color temperature information of the light source of the flash are described as shooting-related data and created by an input device for shooting. In the image processing device for processing the captured image file, the image having a control means for controlling the target image detection process in the image data by using the color temperature information of the light source of the flash. Processing equipment. 11. The image processing apparatus according to claim 10, wherein the image-of-interest detection processing is performed using at least information based on a chromaticity range of a light source of the flash. 12. The image processing apparatus according to claim 10, wherein the captured image file is in JPEG format. 13. In addition to image data, at least ON / OFF information indicating whether or not an image is taken by flash, effective light amount reaching distance information of the flash, and shooting focal length information are described as shooting related data, and shooting is performed. In an image processing method for processing a captured image file created by a video input device, the image processing method further comprises a control step of controlling to perform image correction processing on the image data by using the capturing related data. Processing method. 14. The image correction process is an exposure correction process using an exposure value detected by analysis of the image data and an exposure intensity value calculated from the photographing-related data. The described image processing method. 15. The image processing method according to claim 13, wherein the captured image file is in a JPEG format. 16. In addition to image data, as photographing-related data, at least ON / OFF information indicating whether or not the image has been photographed by flash, effective light amount reaching distance information of the flash, and photographing focal length information are described, and photographing is performed. In an image processing apparatus for processing a captured image file created by a video input device, the image processing apparatus includes control means for controlling to perform image correction processing on the image data by using the capturing related data. Processing equipment. 17. The image correction process is an exposure correction process using an exposure value detected by analysis of the image data and an exposure intensity value calculated from the photographing related data. The image processing device described. 18. The image processing apparatus according to claim 16, wherein the captured image file is in the JPEG format. 19. In addition to image data, as photographing-related data, at least ON / OFF information indicating whether or not an image is taken by flash and color temperature information of a light source of the flash are described and created by an input device for shooting. In a computer-readable control program for controlling an image processing device for processing the captured image file, control is performed to perform image correction processing on the image data by using color temperature information of a light source of the flash. A control program for an image processing apparatus, comprising a program code for causing a computer to execute a control step. 20. The image correction process is a white balance correction process using a white balance constant detected in an analysis process of the image data and color temperature information of a light source of the flash. A control program for the image processing device according to 1. 21. The control program for an image processing apparatus according to claim 19, wherein the captured image file is in JPEG format. 22. In addition to image data, at least ON / OFF information indicating whether or not the image was taken by flash and color temperature information of a light source of the flash are described as shooting-related data and created by an input device for shooting. In a computer-readable control program for controlling an image processing device for processing a captured image file, control is performed to perform a target image detection process in the image data by using color temperature information of a light source of the flash. A control program for an image processing apparatus, comprising a program code for causing a computer to execute the control step to perform. 23. The control program of the image processing apparatus according to claim 22, wherein the attention image detection process is performed using at least information based on a chromaticity range of the light source of the flash. 24. The control program for an image processing apparatus according to claim 22, wherein the captured image file is in JPEG format. 25. In addition to image data, at least ON / OFF information indicating whether or not the image was taken by flash, effective light amount reaching distance information of the flash, and shooting focal length information are described as shooting related data, and shooting is performed. In a computer-readable control program for controlling an image processing device for processing a captured image file created by a video input device, a control is performed to perform an image correction process on the image data by using the capturing related data. A control program for an image processing apparatus, comprising a program code for causing a computer to execute the control step to perform. 26. The image correction process is an exposure correction process using an exposure value detected by analysis of the image data and an exposure intensity value calculated from the photographing-related data. A control program for the described image processing apparatus. 27. The control program for an image processing apparatus according to claim 25, wherein the captured image file is in JPEG format. 28. A storage medium on which the control program of the image processing apparatus according to claim 19 is stored.