JP2019134332A - Image processor and control method therefor - Google Patents

Abstract

To solve the following problem: a conventional image processor cannot acquire an appropriate white balance due to an influence of a light source of any other area than an originally interest area in a normal white balance, particularly in the case of an image with a wide field angle.SOLUTION: The image processor executes adjustment of white balance more suitable for an interest area by improving priority of a detected white area near to the interest area, based on distance information from the interest area to the white area.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an image processing apparatus and a control method thereof, and more particularly to an image processing apparatus capable of performing better white balance adjustment for a region of interest.

  In general, an imaging apparatus using an imaging element such as a digital camera or a digital video camera has a white balance control function for adjusting the color tone of an image obtained by imaging. White balance control includes manual white balance control and automatic white balance control. Manual white balance control is control in which a white subject is imaged in advance to obtain a white balance coefficient, and the calculated white balance coefficient is applied to the entire screen. Auto white balance control, on the other hand, automatically detects white parts from captured images, calculates the white balance coefficient from the average value of each color component on the entire screen, and applies the calculated white balance coefficient to the entire screen. It is.

  Here, the conventional auto white balance control will be briefly described. In the conventional auto white balance control, a color evaluation value is obtained for each block of captured image data, and when the color evaluation value is included in the white detection area, it is determined that the block is white. Then, the white balance coefficient is calculated by obtaining the integral value of the pixels of the block determined to be white.

  Conventional auto white balance control corrects (adjusts) the entire captured image to a unique white balance when there are multiple light sources within the shooting range. Balance correction cannot be performed. Therefore, white balance correction (adjustment) is performed for any one light source, or average white balance correction (adjustment) is performed for all light sources. When such white balance correction is performed, there is a case where an appropriate white balance cannot be obtained for the attention area of the user.

  In order to solve such a problem, means for correcting white balance in accordance with a region limited by a predetermined condition instead of the entire image is known. For example, in Patent Document 1, when the entire image is divided into a plurality of areas and white balance is corrected, the attention area is detected, and the priority of the evaluation value of the divided area including the attention area is increased to perform white balance correction. A method of performing is disclosed. Patent Document 2 discloses a configuration in which a white area (gray area) extracted on a displayed image is superimposed and a user can arbitrarily set a threshold value for determining a white area (gray area). Yes.

JP 2006-2111416 A JP2002-185972

  However, in Patent Literature 1, since the entire screen is divided into regions and the white balance is adjusted using the divided regions including the attention region, there is no white region (gray region) in the attention region. If this is the case, the proper white balance will not be achieved. In Patent Document 2, the user can easily grasp the white (gray) region, and the range of the white (gray) region can be changed by changing the threshold value. However, the white balance of the designated attention region can be changed. No amendment is disclosed. In addition, for example, in an environment where the subject changes while shooting for a long time like a surveillance camera, a configuration in which the user changes the setting every time is troublesome.

  Accordingly, an object of the present invention is to provide means capable of adjusting white balance suitable for a region of interest even when the region of interest does not include a white region.

  In order to achieve the above object, the present invention provides acquisition means for acquiring image data of a subject, detection means for detecting a white area having a color signal within a predetermined range from the image data, and the color of the white area. A calculation unit that calculates a white balance adjustment value of the image data using a signal and a determination unit that determines a region of interest; and the calculation unit determines a distance between the region of interest and at least one of the white regions. Based on this, the white balance adjustment value is calculated.

  According to the present invention, it is possible to perform a suitable white balance adjustment for a region of interest even when the region of interest does not include a white region.

1 is a block diagram illustrating a configuration example of an imaging apparatus according to a first embodiment of the present invention. The flowchart which shows the white balance correction process which concerns on the 1st Embodiment of this invention. The figure which shows the detection of the white area | region which concerns on the 1st Embodiment of this invention. The figure which shows the example of the priority determination of the white area | region which concerns on the 1st Embodiment of this invention The flowchart which shows the white balance correction process which concerns on the 2nd Embodiment of this invention. The figure which shows the relationship of the changed white area extraction range and priority which concerns on the 2nd Embodiment of this invention. The flowchart which shows the white balance correction process which concerns on the 3rd Embodiment of this invention. The figure which shows the example of grouping of the white area | region which concerns on the 3rd Embodiment of this invention. The figure which shows the example of the priority with respect to the grouped white area | region which concerns on the 3rd Embodiment of this invention. The block diagram which shows the structural example of the image processing system which concerns on the 4th Embodiment of this invention. The figure which shows designation | designated of the attention area | region which concerns on the 4th Embodiment of this invention. The figure which shows the display of the priority area which concerns on the 4th Embodiment of this invention. The figure which shows the example of prioritization of the white area | region which concerns on the 5th Embodiment of this invention

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Hereinafter, an example in which an imaging device (camera) is used as an image processing device will be described. However, the present invention is not limited to the imaging device, and can also be applied to image processing in a PC or the like using software.

(First embodiment)
FIG. 1 is a block diagram illustrating a configuration example of an imaging apparatus according to the first embodiment of the present invention. An imaging apparatus 1000 that is an image processing apparatus according to the present embodiment is connected to an external client apparatus 80 (information processing apparatus) via a communication unit 70 so that they can communicate with each other. In the present embodiment, an example is described in which the imaging device 1000 and the client device 80 are separate. However, a part of the imaging device 1000 and the client device 80 (such as an image display and an operation panel) is integrated. It may be. The imaging device 1000 can capture light from the outside to generate an image signal, and can distribute the generated image signal to an external device such as a client device 80 or a server (not shown) via the communication unit 70. is there.

  The image input unit 10 acquires an image by generating an image signal of a surrounding subject by capturing light from outside and capturing the image. A lens group (not shown), an IRCF (Infrared Ray Cut Filter), an image sensor (image sensor), a CDS circuit, an AGC amplifier, and an A / D converter are provided. When a subject is photographed by the image input unit 10, an optical image that has passed through the lens group and the IRCF is formed on an image sensor (image sensor) including a CCD sensor, a CMOS sensor, and the like.

  An image sensor (image sensor) photoelectrically converts an optical image formed on the image sensor and outputs it as an analog image signal. The surface of the image sensor (image sensor) is covered with an RGB color filter such as a Bayer array, for example, so that color photographing is possible. A CDS (Correlated Double Sampling) circuit performs a correlated double sampling process on an electric signal input from an image sensor. An AGC (Automatic Gain Control) amplifier performs an amplification process on the electric signal input from the CDS circuit. The A / D converter converts the analog signal amplified by the AGC amplifier into a digital signal.

  The white area extraction unit 20 detects an area determined to be white from the image signal (color signal) output from the image input unit 10. For example, the area of the image sensor is divided into a mesh shape with a predetermined number of frames (24 × 16 in the present embodiment) and each is used as an evaluation frame, and the color evaluation value calculated based on the RGB signal for each area is a predetermined white An area included in the range evaluation value is detected as a white area. Hereinafter, the “white region” is not limited to white, but includes a gray region, that is, an achromatic region.

  The attention area determination unit 30 determines an area of interest for the image signal output from the image input unit 10. For example, the region of interest is set by a user operation on the client device 80, or the region of interest is determined in response to detecting a specific face or object from the image acquired by the image input unit 10. Is possible.

  The distance calculation unit 40 calculates the distance from the attention area determined by the attention area determination unit 30 to the white area detected by the extraction unit 30.

  The priority determination unit 50 determines the priority for the white area based on the distance information calculated by the distance calculation unit 40.

  The white balance control unit 60 (WB control unit) calculates the white balance gain so that the signal of the white area detected by the white area extraction unit 20 approaches a preset target white. At this time, in the present embodiment, the white balance adjustment value (gain) is determined according to the priority determined by the priority determination unit 50. Then, the white balance (WB) is adjusted using the determined white balance adjustment value (gain).

  The communication unit 70 outputs an image signal whose white balance has been adjusted by the white balance control unit 60 (WB control unit) to an external terminal (such as an information processing device) such as the client device 80. Further, for example, it is used to output the video distribution or the status or processing result of the system, and to input control information for controlling the operation of the system from an external terminal. A control unit (not shown) acquires information input via the communication unit 70 and controls each functional block based on the information.

  The client device 80 acquires and displays the image signal subjected to the above-described image processing via the communication unit 70. The client device 80 may be configured as a part of an external terminal capable of giving a control instruction to the imaging device 1000. The client device 80 may be a touch panel, a PC screen, or the like, and an instruction to the imaging device 1000 may be generated based on an operation on the client device 80.

  A process for obtaining a suitable white balance (WB) for the image signal input from the image input unit 10 and the region of interest will be described with reference to FIG. There are various methods for WB control. In this embodiment, a method of detecting an image area (white area) of a white subject from an image and determining a white balance adjustment value so that the image area is white is used. The WB control performed will be described. FIG. 2 is a flowchart showing white balance correction processing according to the present embodiment. The flowchart in FIG. 2 illustrates a processing procedure executed by controlling each processing block by a control unit (not shown) in the imaging apparatus 1000. This is realized by developing a program stored in a memory (ROM) of the control unit in the memory (RAM) and executing it by the CPU.

  First, in a white region extraction step S10, a white region determined as white is extracted from the image signal (color signal) output from the image sensor. Here, FIG. 3 is a diagram showing detection of a white region according to the first embodiment of the present invention. An image acquired by the image input unit 10 and a white region extracted by the white region extraction unit 20 are shown. Of the mesh-like evaluation areas indicated by broken lines on the image, the inside of the area (white area C) extracted as a white area is indicated by diagonal lines (gray). There are two light sources, light source A and light source B. At this stage, since the white region is extracted from the entire input image signal, the white region C is uniformly formed from the image signal regardless of the light source. Has been extracted.

  Attention area determination step S11, an attention area that preferentially adjusts the white balance is determined for the image signal output from the image sensor. The attention area may be set by a user operation, a specific subject detected using a detection function, an area monitored by the user (an area that is cut out and displayed), or the like. Moreover, it may be set in cooperation with an image analysis area such as detection of abandonment or person detection. For example, an area where an object of interest often appears is obtained from a heat map, and the area is set as an attention area. It is also possible to do.

  In white region determination step S12, it is determined whether a white region has been extracted from the image signal output from the image sensor in white region extraction step S10. If a white area has been extracted, the process proceeds to a distance calculation step S13. If a white area has not been extracted, this process ends. After completing the WB adjustment flow according to the present embodiment, the WB adjustment is performed using another method that does not use the white region, for example, the gain is adjusted so that the integral value of the pixels of the entire screen is close to white. .

  When proceeding to the distance calculation step S13, the distance information from the attention area determined in the attention area determination step S11 to each white area obtained in the white area extraction step S10 is calculated. The distance information is, for example, the number of pixels from the attention area to each white area.

  In priority determination step S14, the priority of each white region is determined from the distance information (number of pixels) calculated in distance calculation step S13.

  FIG. 4 is a diagram illustrating an example of white region priority determination according to the first embodiment of the present invention. In the example shown in steps S13 and S14, the priority for each white region is determined by the white region extraction unit 20, the attention region determination unit 30, the distance calculation unit 40, and the priority determination unit 40. In FIG. 4, the priority E is indicated by a number in the white area C. The smaller the number, the higher the priority. Although the priority of the white area inside the attention area D is not shown, the priority is “0”, which is the highest priority.

  The priority is set according to how many pixels the target white area is away from the target area. The smaller the number of pixels from the target area to the target area, the higher the priority, and the higher the number of pixels, the lower the priority. . The white area C is extracted from the entire image signal, and the priority is set higher for the white area close to the attention area according to the distance (number of pixels) from the attention area D. Thereby, even when there are a plurality of light sources, white balance correction can be performed preferentially with respect to the light source irradiated on the attention area D.

  Note that the attention area D is not limited to an area set according to a user operation or the like, and may be configured such that the position of the attention area D varies according to the movement by detecting a specific subject. . Further, when a white area is detected in the attention area, the white area in the attention area has the highest priority. In that case, it is also possible to adjust the white balance using only the white area within the attention area.

  In the white balance control step S15, white balance (WB) control is performed such that the white region having a higher priority becomes whiter based on the white region extracted in the white region extraction step S10 and the priority determined in step S14. To implement. For example, when the white balance adjustment value (gain) is determined by averaging the signals of the detected white area, the average is calculated by increasing the weight of the white area having a higher priority. By doing so, it is possible to set the white balance gain such that the signal value of the white region having a high priority is closer to the white signal value. In step S15, the white balance adjustment process in the present embodiment ends.

  As described above, according to the present embodiment, white balance adjustment is performed by weighting the white area closer to the attention area, so that it is possible to perform suitable white balance adjustment according to the light source in the vicinity of the attention area.

(Second Embodiment)
Hereinafter, referring to FIG. 5 and FIG. 6, as the second embodiment of the present invention, in the first embodiment, a range in which white areas are extracted according to the ratio of white areas with higher priority is further described. The configuration to be changed will be described.

  FIG. 5 is a flowchart showing white balance correction processing according to the second embodiment. The flowchart in FIG. 5 illustrates a processing procedure executed by controlling each processing block by a control unit (not illustrated) in the imaging apparatus 1000. This is realized by developing a program stored in a memory (ROM) of the control unit in the memory (RAM) and executing it by the CPU.

  First, in a white area extraction step S20, a white area determined as white is extracted from the image signal output from the image sensor. This is the same processing as step S10 in FIG.

  Attention area determination step S21, an attention area that preferentially adjusts the white balance is determined for the image signal output from the image sensor. This is the same processing as step S11 in FIG.

  In white region determination step S22, it is determined whether a white region has been extracted from the image signal output from the image sensor in white region extraction step S20. This is the same processing as step S12 in FIG. If a white area has been extracted, the process proceeds to step S23. If a white area has not been extracted, the process ends.

  In the distance calculation step S23, distance information (number of pixels) from the attention area determined in the attention area determination step S21 to each white area obtained in the white area extraction step S20 is calculated. This is the same processing as step S13 in FIG.

  In the priority determination step S24, the priority of each white region is determined from the distance information (number of pixels) calculated in the distance calculation step S23. This is the same processing as step S14 in FIG.

  In the white region detection range determination step S25, the ratio of the white region having a high priority to the entire region extracted as the white region is determined. The ratio is calculated based on, for example, the area of the white region having a high priority with respect to the area of the entire white region or the number of blocks in the white region having a high priority with respect to the number of blocks detected as the white region. When the white area with high priority occupies a large number and there are few white areas with low priority, the process proceeds to step S26, whereas when the ratio of white areas with high priority is small, the process proceeds to step S27.

  In the white balance control step S26, based on the white region extracted in the white region extraction step S20 and the priority determined in the priority determination step S24, white balance control that makes the white region with a higher priority whiter. To implement. This process is complete | finished above. This is the same processing as step S15 in FIG.

  On the other hand, if the process proceeds to step S27, the white area extraction execution range is changed so as to include many high priority areas in the white area extraction range changing step S27.

  Here, FIG. 6 is a diagram showing the relationship between the changed white area extraction range F and the priority E according to the second embodiment of the present invention. (1) shows the initial setting of the white area extraction range F, and is a solid rectangle including a plurality of evaluation areas (blocks) indicated by a broken line in a mesh shape, which is a range in which the extraction of the white area C is performed. A white area extraction range F1 shown as is the entire field angle. By executing step S27, as shown in (2), the white area extraction range F is selected as the white area extraction range F2, and a white extraction area in which the size of each evaluation area (block) is reduced is newly selected. . By reducing the entire white extraction range, the ratio of the white area C having a higher priority than in the case of (1) increases, and by reducing each evaluation area, the color mixture of each evaluation area is reduced, and more details are obtained. Extraction of a white area C can be executed. Here, in this embodiment, the example in which the entire white extraction range is reduced so that the evaluation area has a predetermined number of frames (for example, 24 × 16) has been described. However, if the processing capability is sufficient, the white extraction range is the entire screen. The configuration may be such that each evaluation region is made finer.

  After changing the size and detection range of each detection area for executing the white area extraction, the process returns to the white area extraction detection step S20, and the white area extraction is executed for the white area extraction range changed in the white area extraction range change step S27. To do. If the processing of step S20 and subsequent steps is executed again and the white area extraction range is changed, and the ratio of the white area having a high priority is greater than or equal to a predetermined value in step S25, the priority is high in step S26. White balance control is performed so that the white area becomes whiter. Then, this process ends.

  In the present embodiment, when the white detection range becomes too small, the white detection range is initialized. For example, a threshold value regarding the ratio of the entire image, such as an area, is provided, and when the white detection range is equal to or less than the threshold value, the white detection range F1 is changed to the initial white detection range F1 as illustrated in FIG.

  As described above, according to the present embodiment, the result of white region extraction with high priority in the vicinity of the subject of interest can be obtained, so that white balance control more suitable for the light source around the subject of interest can be performed.

(Third embodiment)
Hereinafter, with reference to FIG. 7, FIG. 8, and FIG. 9, the extracted white areas are grouped according to the third embodiment of the present invention, and each grouped white area is set according to the distance from the attention area. The white balance adjustment based on the priority will be described.

  FIG. 7 is a flowchart showing white balance correction processing according to the third embodiment. The white area C extracted from the image signal input from the image input unit 10 is grouped, and the priority E corresponding to the distance from the attention area D is determined for the grouped white area C, and the attention area A process for adjusting white balance (WB) with respect to D is shown. The flowchart in FIG. 7 illustrates a processing procedure executed by controlling each processing block by a control unit (not illustrated) in the imaging apparatus 1000. This is realized by developing a program stored in a memory (ROM) of the control unit in the memory (RAM) and executing it by the CPU.

  First, in a white region extraction step S30, a white region determined as white is extracted from the image signal (color signal) output from the image sensor. This is the same processing as step S10 in FIG.

  Attention area determination step S31, an attention area D in which white balance is preferentially adjusted with respect to the image signal output from the image sensor is determined. This is the same processing as step S11 in FIG.

  In white area determination step S32, it is determined whether the white area C has been extracted from the image signal output from the image sensor in white area extraction step S30. This is the same processing as step S12 in FIG. If the white area C has been extracted, the process proceeds to step S33. If the white area C has not been extracted, the process ends.

  In the white area grouping step S33, adjacent areas having similar luminance and color differences are grouped into the same group for each white area C extracted in the white area extraction step S30. FIG. 8 is a diagram illustrating an example of white area grouping related to the processing of the white area grouping step S33. Based on the luminance and color difference information, adjacent white areas extracted from the white area are grouped based on the similarity and divided into groups G1 to G7.

  In the distance calculation step S34, distance information (number of pixels) from the attention area D determined in the attention area determination step S31 to each white area group obtained in the white area grouping step S33 is calculated. At this time, the distance information may be, for example, the distance to the nearest white area among the white areas included in the group, or may be the distance from the center of the grouped area or the position of the center of gravity.

  In priority determination step S35, the priority E of each white area group is determined from the distance information calculated in distance calculation step S34. FIG. 9 is a diagram illustrating an example of prioritizing a grouped white area according to the processing of the priority determination step S35. Priorities according to the distance from the attention area D are set for the areas divided into groups G1 to G7. In FIG. 9, G1 is set to priority 1, G4 is set to priority 2, and G3 is set to priority 3. Since the white area is grouped, the white area having a higher priority is expanded as compared with the case where the priority is set for each of the white areas.

  In the white balance control step S36, the white balance (WB) is set so that the white region group having a higher priority becomes white based on the priority determined in step S35 for the white regions grouped in step S33. adjust. Above, the process of this flowchart is complete | finished.

  As described above, according to the third embodiment, a wider white area can be obtained, and more suitable white balance (WB) control can be performed by increasing the number of evaluation objects.

(Fourth embodiment)
Hereinafter, a configuration in which a user designates a region of interest in an input image via a communication unit according to a fourth embodiment of the present invention will be described with reference to FIGS. In addition, the same code | symbol is attached | subjected about the structure similar to the above-mentioned embodiment, and the description is abbreviate | omitted.

  FIG. 10 is a block diagram illustrating a configuration example of an image processing system according to the fourth embodiment of the present invention. An imaging apparatus 1000 that is an image processing apparatus according to the present embodiment is connected to an external client apparatus 80 (information processing apparatus) via a communication unit so that they can communicate with each other. The client device 70 can communicate with an external device such as the imaging device 1000 or a server via a communication unit (not shown).

  The client device 80 is configured as a part of an external terminal capable of giving a control instruction to the imaging device 1000. The client device 80 includes an operation unit including an attention area setting UI unit 180 and a white area display UI unit 190, and an instruction to the imaging apparatus 1000 is generated according to an operation on the operation unit.

  The attention area setting UI unit 180 is an interface for setting the attention area, and includes a screen on the computer and operation means. The user designates a region of interest via a touch panel on the computer that is the region-of-interest setting UI unit 180 or an external operation unit, and transmits it to the imaging apparatus 1000 via a communication unit (not shown). The imaging apparatus 1000 that has received the attention area set via the communication unit 70 designates the attention area to the attention area determination unit 130.

  The white area display UI unit 190 is an interface for displaying white areas and priorities, and is a display related to setting of image signals, white areas, and priorities output from the imaging apparatus 1000 via a communication unit (not shown). To inform the user. For example, the image information can be displayed with the white area and the priority superimposed, and the user can be notified of which area is used to control the white balance.

  FIG. 11 is a diagram illustrating that the user designates a region of interest using the region-of-interest setting UI unit 180. The user can set an arbitrary region as a region of interest on the UI and set it in the priority region determination unit 50 of the imaging apparatus 1000 through a communication unit (not shown).

  FIG. 12 is a diagram showing that a white region with a high priority for preferentially adjusting white balance (WB) is displayed on the white region display UI unit 190. The user can check the white area displayed on the UI and check whether the area intended by the user is used as a white balance (WB) correction range.

  As described above, according to the fourth embodiment, an arbitrary attention area can be set from an external client device, and a white area with a high priority is displayed, and the white balance (WB) is adjusted to which area. It can be easily confirmed whether it is adjusted.

(Fifth embodiment)
Here, even when the distance on the image surface is short, the spatial distance of the subject may be long. For example, in a scene where there is no object behind the subject of interest and there is depth, if priority is given only by the distance on the image surface, the distance may actually be far and the light source may be different . In such a case, the white balance (WB) is adjusted more suitably for the attention area by acquiring the spatial positional relation of the subject and weighting the white area in consideration of the positional relation. Is possible.

  In the image processing apparatus, the spatial positional relationship of the subject is acquired. Since the acquisition method uses a known technique, a detailed description is omitted. For example, it is possible to acquire distance measurement information from phase difference information by an image sensor of an imaging apparatus or output of a distance measurement sensor. In addition, a distance map of a structure within the imaging range may be registered in advance in the client device.

  FIG. 13 is a diagram showing an example of prioritizing white areas according to the fifth embodiment of the present invention. (1) shows the result of assigning the priority of the white region C according to the first embodiment. The result of prioritization according to this embodiment is shown in (2). Of the white region C to which the priority is assigned in (1), the excluded region H in which the mesh is blacked out is excluded from the white extraction result. The excluded area H is a subject that exists at a position away from the attention area D in the depth direction, and may have a light source environment different from the attention area D. Therefore, the exclusion area H is more suitable by excluding this area. White balance (WB) can be acquired.

  As described above, according to the fifth embodiment, since the priority of the white area is determined based on the distance from the subject of interest in the real space, the priority of the area that is separated in the depth direction and has a different light source is lowered. White balance adjustment more suitable for the subject of interest is possible.

  As mentioned above, although preferable embodiment of this invention was described, this invention is not limited to these embodiment, A various deformation | transformation and change are possible within the range of the summary. The present invention should be adapted by being changed as appropriate according to the target circuit form within the scope of the technical idea of the present invention. For example, the camera described as the imaging device in the above-described embodiment can be applied to a digital still camera or a digital video camera. The image processing apparatus is not limited to processing inside the imaging apparatus, and can be applied to an external computer apparatus.

  Further, the present invention can be embodied as a system, apparatus, method, computer program, or recording medium, for example. Specifically, the present invention can be applied to a system composed of a plurality of apparatuses even if it is realized by one apparatus. May be. Each unit of the image processing apparatus according to the present embodiment and each step of the control method of the image processing apparatus can be realized by operating a program stored in a memory of a computer or the like. The computer program and a computer-readable recording medium on which the program is recorded are included in the present invention.

  The present invention supplies a program that realizes one or more functions of the above-described embodiments to a system or apparatus via a network or a storage medium, and one or more processors in a computer of the system or apparatus read and execute the program This process can be realized. It can also be realized by a circuit (for example, ASIC) that realizes one or more functions.

DESCRIPTION OF SYMBOLS 1000 Imaging device 10 Image input part 20 White area extraction part 30 Attention area determination part 40 Distance calculation part 50 Priority determination part 60 White balance control part 70 Communication part 80 Client apparatus

Claims (19)

Acquisition means for acquiring image data of a subject;
Detecting means for detecting a white region having a color signal within a predetermined range from the image data;
A calculation unit that calculates a white balance adjustment value of the image data using a color signal of the white region; and a determination unit that determines a region of interest.
The image processing apparatus, wherein the calculating means calculates the white balance adjustment value based on a distance between the attention area and at least one of the white areas.   The image processing apparatus according to claim 1, wherein the calculation unit calculates a white balance adjustment value using a color signal of a white area included at a predetermined distance from the attention area. First distance calculation means for calculating a distance for each of the white areas from the attention area;
First weighting means for increasing the priority of the white region as the distance from the region of interest to the white region is closer,
The image processing apparatus according to claim 1, wherein the calculation unit calculates the white balance adjustment value based on a priority by the first weighting unit. Change means for changing the detection range or detection size of the white area by the detection means;
The change unit changes the detection range or the detection size so that a ratio of a white area included in a predetermined distance from the attention area with respect to the detection range is equal to or greater than a predetermined value. 4. The image processing apparatus according to any one of items 3.   The said changing means changes the said detection range or detection size so that the ratio of the white area | region where the priority by the said 1st weighting means is high with respect to the said detection range becomes more than predetermined. 5. The image processing apparatus according to 4.   The image processing apparatus according to claim 4, wherein the changing unit initializes the detection range or the detection size when the detection range becomes smaller than a predetermined value. Second distance calculating means for acquiring depth information of the subject and calculating a spatial distance to the region of interest;
The image processing apparatus according to claim 1, wherein the calculation unit calculates the white balance adjustment value based on the spatial distance. Grouping means for grouping adjacent white regions based on the similarity of luminance and color difference;
Third distance calculating means for calculating a distance for each group of the white area from the attention area;
Second weighting means for determining a priority for each group based on the calculated distance;
Further comprising
The image processing apparatus according to claim 1, wherein the calculation unit calculates the white balance adjustment value based on a distance from the attention area to at least one of the groups.   The image processing apparatus according to claim 1, wherein the determination unit determines the attention area in accordance with a user operation on the UI unit.   The image processing apparatus according to claim 9, wherein the determination unit is connected to the UI unit via communication to determine the attention area in response to reception of the user operation.   The UI unit can display at least one of the white area, the white area used for the white balance adjustment, the grouped white area, and the priority with an image. The image processing apparatus according to 10.   The image processing apparatus according to claim 1, further comprising: an output unit that outputs the calculated white balance adjustment value together with image data to an external apparatus through communication.   13. The white balance adjustment value is calculated using the signal value of the white area in the attention area when the white area is detected in the attention area. The image processing apparatus according to any one of the above. Acquisition means for acquiring image data of a subject;
Detecting means for detecting a white region having a color signal within a predetermined range from the image data;
Adjusting means for adjusting a white balance of the image data using a color signal of the white region;
Determining means for determining a region of interest;
The image processing apparatus according to claim 1, wherein the adjustment unit adjusts the white balance so that the white area closer to the attention area has a color signal closer to a signal value indicating white in the white area.   The image processing apparatus according to claim 14, wherein the adjustment unit adjusts a white balance using a color signal of a white area included at a predetermined distance from the attention area. A control method for an image processing apparatus, comprising:
Obtaining image data of the subject;
Determining a region of interest;
Detecting a white region having a color signal within a predetermined range from the image data;
And a step of adjusting a white balance based on a distance between the region of interest and at least one of the white regions.   The method of controlling an image processing apparatus according to claim 16, wherein in the step of adjusting the white balance, the white balance is adjusted so that a white region closer to the region of interest is closer to white.   A computer program for causing a computer to execute each step according to claim 16 or 17.   The computer-readable recording medium which described the program of Claim 18.