JP2005208886A - Image correction apparatus and image correction program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image correction apparatus and an image correction program for applying image correction to an image in which correction designation by a manual operation is easily performed with the sufficient degree of freedom. <P>SOLUTION: The image correction apparatus is provided with: an analyzing part which applies predetermined image analysis to an image to calculate the correction amount or correction target of image correction to the image; a correction changing part in which a change amount is designated by an operation, and the correction amount or correction target calculated by the analyzing part is changed according to the change amount; an image correcting part which applies the image correction to the image to acquire an image having the correction amount changed by the correction changing part or the correction result corresponding to the correction target; and a range setting part which sets the range of the change amount which can be designated for the correction changing part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image correction apparatus and an image correction program that perform image correction on an image.

  Conventionally, there is known an automatic correction technique for performing image analysis using image data representing an image and performing image correction on the image data according to the result of the image analysis. Correction devices and image correction programs are also known. In this automatic correction, in general, various image corrections such as density correction, white balance adjustment (color temperature adjustment), saturation adjustment, sharpness conversion, etc. are performed. However, automatic correction is not universal and is insufficiently corrected or corrected. There may be problems such as being excessive or the direction of correction being poor.

Such troubles may depend on, for example, model differences or user preferences. In such cases, the automatic correction can be customized by reflecting the model differences or user preferences in the automatic correction. It has been proposed to avoid problems (see, for example, Patent Document 1).
JP 2002-16874 A

  However, even when automatic correction is customized using the technique described in Patent Document 1, since automatic correction is premised on image analysis using image data, the fundamental limit of the image analysis is limited. Due to the inaccuracies in the analysis caused, defects can still occur in the correction for individual images. For this reason, the image correction apparatus and the image correction program need a function of instructing appropriate correction by manual operation and changing the correction when such a problem occurs.

  Although the conventional image correction apparatus and the image correction program are provided with such a correction instruction function by manual operation, such correction instruction operation is complicated in the conventional image correction apparatus and the like. In addition, since the complexity increases as the degree of freedom of operation increases, the degree of freedom is often insufficient in conventional image correction devices and the like.

  In view of the above circumstances, an object of the present invention is to provide an image correction apparatus and an image correction program capable of easily performing the correction instruction as described above with a sufficient degree of freedom.

The image correction apparatus of the present invention that achieves the above-described object provides:
An analysis unit that performs a predetermined image analysis on the image and obtains a correction value that defines image correction for the image;
A correction change unit that specifies a change amount by an operation and changes a correction value obtained by the analysis unit according to the change amount;
An image correction unit that obtains an image having a correction result corresponding to the correction value after being changed by the correction change unit by performing image correction on the image;
And a range setting unit that sets a range of change amounts that can be specified for the correction change unit.

  Here, the “correction value” may be a correction amount in which the correction is defined by the difference between the states before and after the correction, or may be a correction target value in which the correction is defined only in the state after the correction.

  The setting by the range setting unit may be an automatic setting based on an analysis or the like, or may be a setting according to a manual operation.

  Since the image correction apparatus of the present invention includes the above-described range setting unit, the operation range for correction change can be limited to a necessary and sufficient range according to experience, image analysis, preference, and the like. Therefore, according to the image correction apparatus of the present invention, it is possible to eliminate an unnecessary instruction range, and as a result, it is possible to reduce the complexity of the operation and ensure a sufficient degree of freedom.

The image correction apparatus of the present invention includes:
"The above range setting unit sets the range of change amount that can be specified for the correction change unit to a range according to the operation."
It may be a mode,
“The range setting unit sets the range of change amount that can be specified for the correction change unit with the correction value obtained by the analysis unit as a reference.”
Or may be
The range setting unit sets the range of the change amount that can be specified for the correction change unit to a range according to the result of the image analysis performed when the correction value is obtained by the image analysis unit. is there"
It may be an aspect.

  In the aspect set to the range according to operation, the range of change amount can be manually set to the range according to experience and preference.

  In the aspect in which the correction amount or the correction target is set as a reference, a range corresponding to the correction result of the automatic correction is automatically set.

  Further, in the aspect of setting the range according to the result of the image analysis, for example, when a plurality of correction value candidates are obtained by the analysis for automatic correction, the first candidate is adopted for the automatic correction, and the change range Can be applied based on correction values other than the head candidate.

In the image correction apparatus of the present invention,
"The analysis unit calculates the correction value for each of a plurality of types of image correction,
In the correction change unit, the change amount is designated for each of the plurality of types of image correction,
The range setting unit sets a range of change amounts that can be specified for the correction change unit for each of the plurality of types of image corrections.
This form is suitable.

  In the automatic correction based on the image analysis, various image corrections as described above are generally performed. For such various image corrections, it is desirable that a change range suitable for each can be set. If each change range can be set in this way, for example, a certain user uses only an image under a specific light source, and therefore, for example, the change range can be set to 0 for color temperature adjustment.

An image correction program of the present invention that achieves the above object is provided as follows:
Built into a computer, on that computer,
An analysis unit that performs a predetermined image analysis on the image and obtains a correction value that defines image correction for the image;
A correction change unit that specifies a change amount by an operation and changes a correction value obtained by the analysis unit according to the change amount;
An image correction unit that obtains an image having a correction result corresponding to the correction value after being changed by the correction change unit by performing image correction on the image;
And a range setting unit that sets a range of a change amount that can be specified for the correction change unit.

  According to the image correction program of the present invention, the components of the image correction apparatus of the present invention can be easily realized by a computer.

  It should be noted that the image correction program according to the present invention is only shown in its basic form here, but this is only for avoiding duplication, and the image correction program according to the present invention includes only the above basic form. Instead, various forms corresponding to each form of the image correction apparatus described above are included.

  As described above, according to the present invention, a correction instruction by manual operation can be easily performed with a sufficient degree of freedom.

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

  FIG. 1 is a diagram illustrating an example of a system to which an embodiment of the present invention is applied.

  In the example shown in this figure, a digital still camera 20 is connected to the computer 10, and image data obtained by photographing with the digital still camera 20 is taken into the computer 10 via the USB cable 21.

  Here, an embodiment of the image correction program of the present invention is incorporated in the computer 10, and an embodiment of the image correction apparatus of the present invention is constructed on the computer 10 by this image correction program. In addition to the function as an image correction device, functions as various processing devices that use image data are also built on the computer 10.

  The image data captured from the digital still camera 20 is subjected to image correction processing by an image correction device constructed on the computer 10. The characteristic feature of the embodiment of the present invention resides in the processing operation in the computer 10. First, the hardware of the computer 10 will be described below.

  This personal computer 10 has an appearance configuration, a main body device 11, an image display device 12 that displays an image on a display screen 12a according to an instruction from the main body device 11, and a main body device 11 according to various key operations. A keyboard 13 for inputting information and a mouse 14 for inputting an instruction corresponding to, for example, an icon or the like displayed at that position by designating an arbitrary position on the display screen 12a are provided. The main unit 11 has a flexible disk loading port 11a for loading a flexible disk and a CD-ROM loading port 11b for loading a CD-ROM.

  FIG. 2 is a block diagram showing the hardware configuration of the computer.

  In the main unit 11 shown in FIG. 1, a CPU 111 that executes various programs, a main memory 112 that is read out from a program stored in the hard disk device 113 and developed for execution by the CPU 111, various programs, data, and the like Is stored in the hard disk device 113, the flexible disk 31 is loaded, the FD drive 114 is accessed to access the loaded flexible disk 100, the CD-ROM 32 is loaded, and the CD-ROM drive 115 is accessed to the loaded CD-ROM 32. The I / O interface 116 connected to the digital still camera 20 (see FIG. 1) and receiving image data from the digital still camera 20 is built in. These various elements and the image display device 12 shown in FIG. , Keyboard 13, Mouse 14 are connected to each other via a bus 15.

  Here, the CD-ROM 32 stores an embodiment of the image correction program of the present invention that causes the personal computer 10 to operate as an embodiment of the image correction apparatus of the present invention. The CD-ROM 32 is a CD-ROM 32. The image correction program loaded in the ROM drive 115 and stored in the CD-ROM 32 is uploaded to the personal computer 10 and stored in the hard disk device 113.

  FIG. 3 is a diagram showing an embodiment of the image correction program of the present invention.

  The storage medium 30 shown in FIG. 3 is not limited as long as it is a storage medium in which the image correction program 40 is stored. For example, when the image correction program 40 is stored in a CD-ROM, the storage medium 30 shown in FIG. -ROM means the hard disk device when the image correction program 40 is loaded and stored in the hard disk device, or the flexible disk when the image correction program 40 is downloaded to the flexible disk.

  The image correction program 40 is executed in the computer 10 shown in FIG. 1 and operates the computer 10 as an image correction device that performs correction processing on an image. The image correction program 40 is an analysis unit 41, a correction change unit 42, and an image correction unit. Part 43 and range setting part 44.

  FIG. 4 is a functional block diagram showing an embodiment of the image correction apparatus of the present invention.

  This image correction apparatus 50 is configured on the computer 10 by installing and executing the image correction program 40 of FIG. 3 on the computer 10 shown in FIG.

  The image correction apparatus 50 includes an analysis unit 51, a correction change unit 52, an image correction unit 53, and a range setting unit 54. The analysis unit 51, the correction change unit 52, the image correction unit 53, and the range setting unit. 54 is configured on the computer 10 by an analysis unit 41, a correction change unit 42, an image correction unit 43, and a range setting unit 44 that constitute the image correction program 40 shown in FIG. As described above, each element of the image correction apparatus 50 illustrated in FIG. 4 corresponds to each element of the image correction program illustrated in FIG. 3, and each element illustrated in FIG. 4 corresponds to the hardware of the computer 10 illustrated in FIG. 1. 3 is different from that shown in FIG. 3 in that each element is composed only of the application program.

  The analysis unit 51, the correction change unit 52, the image correction unit 53, and the range setting unit 54 configured on the computer 10 are respectively an analysis unit, a correction change unit, an image correction unit, and a range setting unit in the present invention. It corresponds to each example.

  Hereinafter, the components of the image correction apparatus 50 shown in FIG. 4 will be outlined.

  The analysis unit 51 analyzes the image represented by the image data captured from the digital still camera 20 shown in FIG. 1, and calculates parameters for automatic image correction. In this embodiment, as an example of image analysis, color temperature (light source white balance) analysis and brightness (density) analysis are performed, and a color temperature correction value and a brightness correction value are obtained.

  The correction changing unit 52 displays a GUI (Graphical User Interface) operation screen on the image display device 12 shown in FIGS. 1 and 2 and receives an instruction for manual correction via the GUI operation screen.

  Further, the image correction unit 53 performs image correction processing on the image data according to the correction value obtained by the analysis unit 51 and the instruction received by the correction change unit 52.

  The range setting unit 54 sets a manual correction instructable range on the GUI operation screen displayed by the correction change unit 52. The range setting unit 54 displays a range setting screen, and receives a condition setting for manual setting of the range itself and automatic setting of the range on the range setting screen.

  Hereinafter, details of setting on the range setting screen and details of the operation of the image correction apparatus 50 will be described.

  FIG. 5 is a diagram illustrating a range setting screen.

  The range setting screen 60 includes a radio button 61, a numerical value setting field 62, and a unit setting field 63.

  The radio button 61 is used to select whether the manual correction instructionable range is set automatically or manually, and is clicked by the mouse 14 shown in FIGS. When the automatic setting is selected by the radio button 61, an analysis result performed by the analysis unit 51 of FIG. 4 is used to obtain a correction value in automatic image correction, and an appropriate range can be instructed for manual correction. Set as a range. Details of this automatic setting will be described later.

  The numerical value setting field 62 and the unit setting field 63 are effective when the manual setting is selected by the radio button 61, and the numerical value setting field 62 is input with a numerical value indicating a manual correction instructable range. In 63, the unit for the value is selected. Here, “degree” and “%” can be selected as a unit for “color temperature”, and “Key” and “%” can be selected as a unit for “density”. However, the unit “Key” is a special unit in which “10” Key is assigned to “1” of density which is generally a dimensionless amount.

  When “K” or “Key” is selected in the unit setting field 63, the numerical value input in the numerical value setting field 62 represents the absolute value of the manual correction instructable range. On the other hand, when “%” is selected as a unit in the unit setting field 63, the manual correction instructable range is set as a relative range according to the result of automatic image correction. The numerical value input in the setting column 62 represents a relative value. For example, when the value after correction by automatic image correction for the color temperature is 5750K and the range of “20%” is set by the numerical value setting field 62 and the unit setting field 63, the manual correction instructable range is Plus or minus 1150K.

  In the range setting unit 54 shown in FIG. 4, setting is performed via the range setting screen 60 described above, and the image correction apparatus 50 operates as described below on the premise of this setting.

  FIG. 6 is a flowchart showing the operation procedure of the image correction apparatus according to this embodiment.

  In the image correction apparatus, as described above, when image data is captured from a digital still camera (step S01), first, an index image in which an image represented by the image data is reduced is created (step S02). Next, the image represented by the image data is analyzed, a correction value in automatic image correction is obtained (step S03), and a manual correction instructable range for the result of the automatic image correction is calculated (step S04). ). A method for calculating the correction value and the instructable range will also be described later.

  When the correction value and the instructable range are obtained, an image correction screen for confirming the result of automatic correction with an index image and instructing manual correction is displayed on the image display device 12 shown in FIGS. (Step S05).

  FIG. 7 is a diagram illustrating an image correction screen.

  On the image correction screen 70, the original index image 71a created in step S02 of FIG. 6 and the corrected index image 71b obtained by performing image correction on the original index image 71a are displayed. The user of the image correction apparatus confirms whether or not the image correction is appropriate with reference to these index images.

  Further, the image correction screen 70 is provided with a change instruction column 72 for changing the result of automatic correction and instructing manual correction. The change instruction column 72 has a manual correction instructable range. It is shown as a two-dimensional coordinate space. As two coordinate axes constituting the two-dimensional coordinate space, here, a color temperature axis 72a and a brightness axis 72b are shown, and the intersection (origin) of these axes 72a and 72b is the result of automatic correction. It corresponds to. Furthermore, a pointer 73 is displayed in the change instruction column 72, and the position corresponding to the difference between the position of the pointer 73 and the origin is determined by determining the position of the pointer 73 in the two-dimensional coordinate space by operating the mouse or the like. A change will be instructed.

  Further, an OK button 74 is provided on the image correction screen 70, and when the OK button 74 is clicked, the end of manual correction is confirmed.

  Here, a method for calculating the automatic correction value and the correction possible instruction range will be described.

  FIG. 8 is an explanatory diagram for explaining a method of calculating the automatic correction value and the correction possible instruction range.

  Here, the correction of the color temperature will be described with an example.

  When the automatic correction value of the color temperature is obtained, first, a gray point in the image is obtained by image analysis, and the color temperature of the light source in the image is estimated based on the gray point.

In FIG. 8, the Lab color space is shown two-dimensionally with the L ^* axis omitted, and in the image analysis, the intersection O of the a ^* axis and the b ^* axis is centered on the Lab color space. The distribution of colors existing in the region R within a predetermined distance is analyzed. For example, for an image, three colors corresponding to the three points P1, P2, and P3 shown in this figure are included in the image as colors existing in the region R, and these colors occupy the image. If the area is P1>P3> P2, it is determined that the color corresponding to the point P1 is a gray point in this image. The color corresponding to the point P1 determined as the gray point is the color of the light source, and the color temperature (white balance) of the light source is estimated from the distance between the point P1 and the intersection O. If the estimated color temperature is, for example, 4000K, a correction value for correcting a difference from a preset reference value (for example, 6500K) is calculated. However, not all of the differences are corrected, but a correction value for correcting 70% of the differences is calculated in order to obtain an appropriate white balance while leaving a shooting atmosphere due to the difference in the light source. In the present embodiment, the automatic correction value of the color temperature is set as the correction target value T1.
T1 = 4000 + (6500-4000) × 0.7 = 5750
Thus, 5750K is obtained as the color temperature after the automatic correction.

  For the correction result corresponding to the automatic correction value obtained in this way, the manual correction specifiable range is obtained as follows according to the setting on the range setting screen 60 shown in FIG.

  When the automatic setting is selected on the range setting screen 60, the distance between the point P1 shown in FIG. 8 and the other points P2 and P3 is obtained. Then, a color temperature difference corresponding to these distances is obtained, and the color temperature difference is used as the width of the specifiable range.

On the other hand, when manual setting is selected on the range setting screen 60 and the range is set to “20%”, for example, 5750K obtained as the color temperature after the automatic correction is used as a reference, The width W of the specifiable range is
W = 5750 × 0.2 = 1150
Thus, a range of plus or minus 1150K is obtained.

  When manual setting is selected on the range setting screen 60 and the range is set in units other than “%”, the range as set is naturally used regardless of image analysis.

  When the automatic correction value and the correction range are calculated in this manner at step S03 and step S04 in FIG. 6, in step S05, the image correction according to the obtained automatic correction value is performed on the image correction screen 70 shown in FIG. The applied correction index image 71b and a change instruction column 72 having a two-dimensional coordinate space representing the obtained correction range are displayed. The correction range displayed as the two-dimensional coordinate space in the change instruction field 72 is a range in which the degree of freedom of manual correction is sufficiently secured, and the appropriate manual operation is indicated by such a range being indicated. It helps to register the correction and an appropriate manual correction can be easily specified.

Thereafter, in step S06, the OK button 74 shown in FIG. 7 is clicked to determine whether or not the manual correction has been completed. If the manual correction has not been completed, the correction instruction field 72 in FIG. Instructed by operation (step S07). In the change instruction column 72, as described above, the correction change is instructed by manually determining the position of the pointer 73. For example, when a position of 20% is determined on the minus side with respect to the range of plus or minus 1150K obtained as described above, the target value T2 for manual correction is
T2 = 5750-1150 × 0.2 = 5520
Thus, 5520K is obtained as the color temperature after the correction change by manual correction.

  When the correction change is instructed in this way, the change is reflected in the correction index image 71b of FIG. 7 (step S08), and the procedure is repeated by returning to step S05.

  On the other hand, if it is determined in step S06 that the manual correction has been completed by clicking the OK button 74 shown in FIG. 7, the image according to the correction value finally obtained through the automatic correction and the manual correction. A correction process is performed on the image data captured in step S01 (step S09). As described above, the image data captured in step S01 is only subjected to the image correction process according to the finally obtained correction value, so that it is necessary for the manual correction instruction. It is possible to reduce the burden of calculation processing.

  The image data subjected to such image correction processing is transferred to other data processing executed by the computer 10 in FIG. 1 (step S10).

  As described above, according to the image correction apparatus of the present embodiment, a correction instruction by manual operation can be easily performed with a sufficient degree of freedom.

  In the above description, the index image is corrected until the manual correction instruction is completed. After all the manual correction instructions are completed, the final correction process is performed on the original image data. However, in the present invention, the original image data may be corrected each time a trial instruction is given in manual correction.

  Further, as described above, the analysis and correction of the color temperature and density are merely examples, and it is natural that the image analysis and image correction referred to in the present invention are not limited to this. As other image analysis and image correction, for example, analysis and correction of saturation and sharpness may be employed.

It is a figure which shows the example of the system with which one Embodiment of this invention is applied. It is a block diagram showing the hardware constitutions of a computer. It is a figure which shows one Embodiment of the image correction program of this invention. It is a functional block diagram showing one Embodiment of the image correction apparatus of this invention. It is a figure showing the range setting screen. It is a flowchart showing the operation | movement procedure of the image correction apparatus in this embodiment. It is a figure showing an image correction screen. It is explanatory drawing for demonstrating the calculation method of the automatic correction value and the correction possible instruction | indication range.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Computer 11 Main body apparatus 11a Flexible disk loading slot 11b CD-ROM loading slot 12a Display screen 12 Image display apparatus 13 Keyboard 14 Mouse 15 Bus 111 CPU
112 Main Memory 113 Hard Disk Device 114 FD Drive 115 CD-ROM Drive 116 I / O Interface 20 Digital Still Camera 21 USB Cable 30 Storage Medium 31 Flexible Disk 32 CD-ROM
DESCRIPTION OF SYMBOLS 40 Image correction program 41 Analysis part 42 Correction change part 43 Image correction part 44 Range setting part 50 Image correction apparatus 51 Analysis part 52 Correction change part 53 Image correction part 54 Range setting part 60 Range setting screen 61 Radio button 62 Numerical value setting column 63 Unit setting column 70 Image correction screen 71a Original index image 71b Correction index image 72 Change instruction column 72a Color temperature axis 72b Brightness axis 73 Pointer 74 OK button

Claims (6)

An analysis unit that performs a predetermined image analysis on the image and obtains a correction value that defines image correction for the image;
A correction change unit that specifies a change amount by an operation and changes the correction value obtained by the analysis unit according to the change amount;
An image correction unit that obtains an image having a correction result corresponding to the correction value after being changed by the correction change unit by performing image correction on the image;
An image correction apparatus comprising: a range setting unit that sets a range of change amounts that can be specified for the correction change unit.   The image correction apparatus according to claim 1, wherein the range setting unit sets a range of a change amount that can be specified to the correction change unit to a range corresponding to an operation.   The image according to claim 1, wherein the range setting unit sets a range of a change amount that can be specified for the correction changing unit with a correction value obtained by the analysis unit as a reference. Correction device.   The range setting unit sets the range of the change amount that can be specified for the correction change unit to a range according to the result of image analysis performed when a correction value is obtained by the image analysis unit. The image correction apparatus according to claim 1, wherein the image correction apparatus is provided. The analysis unit calculates the correction value for each of a plurality of types of image correction;
The correction change unit is such that the change amount is specified for each of the plurality of types of image corrections,
The image correction apparatus according to claim 1, wherein the range setting unit sets a range of change amounts that can be specified for the correction change unit for each of the plurality of types of image correction. Embedded in a computer, on the computer,
An analysis unit that performs a predetermined image analysis on the image and obtains a correction value that defines image correction for the image;
A correction change unit that changes the correction amount or the correction target that is specified by an operation and is obtained by the analysis unit according to the change amount;
An image correction unit that obtains an image having a correction result corresponding to a correction amount or a correction target after being changed by the correction change unit by performing image correction on the image;
An image correction program comprising: a range setting unit that sets a range of change amounts that can be specified for the correction change unit.

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