Patent Description:
Conventionally, image processing such as NR processing for removing noise components is applied to an image captured by an image capturing apparatus, so that the image is corrected to become a high-quality image. In order to obtain a high-quality image using NR processing, it is necessary to determine shooting parameters such as an aperture value, shutter speed, and ISO sensitivity at the time of shooting, taking into consideration the noise reduction effect of NR processing. For example, increasing the ISO sensitivity increases the intensity of the noise component, but it is possible to increase the shutter speed, so that the effects of camera shake and subject shake are reduced. Therefore, when shooting a moving subject in a dark environment, it is desired to increase the ISO sensitivity within an acceptable range of the intensity of the noise component after NR processing is performed and determine shooting parameters such as shutter speed and aperture value.

Further, there are cases where the image processing for a captured image is performed not in the image capturing apparatus but in the image processing apparatus outside the image capturing apparatus. For example, <CIT> discloses a technique that an image captured by an image capturing apparatus and model information of the image capturing apparatus are transferred to an external image processing apparatus, and the external image processing apparatus performs image quality correction on the transferred image based on image quality correction parameters recorded for each model of the image capturing apparatus.

In addition, in recent years, with the development of advanced image processing technology using statistical feature amounts and the like, advanced image processing that is difficult to perform in an image capturing apparatus is executed by an image processing apparatus outside the image capturing apparatus. This makes it possible to obtain higher quality images. In this case, it is necessary to determine the shooting parameters at the time of shooting in consideration of the result of image processing (for example, the degree of noise reduction) by the external image processing apparatus.

However, in the conventional technique, it has not been possible to separately determine the optimum shooting parameters suitable for cases where the image processing is performed within an image capturing apparatus and suitable for cases where the image processing is performed in an image processing apparatus outside the image capturing apparatus. Document <CIT> discloses an image capturing apparatus according to the preamble of claim <NUM>.

The present invention has been made in consideration of the above situation, and determines shooting parameters corresponding to the image processing and suitable for shooting scenes.

According to the present invention, provided is an image capturing apparatus as specified in any one of claims <NUM> to <NUM>.

Further, according to the present invention, provided is an image capturing system as specified in claim <NUM>.

Furthermore, according to the present invention, provided is a control method as specified in claim <NUM>.

Further, according to the present invention, provided is a computer program as specified in claim <NUM>.

The accompanying drawings, which are incorporated in and constitute a part of the specification, illustrate embodiments of the invention, and together with the description, serve to explain the principles of the invention.

Note, the following embodiments are not intended to limit the scope of the claimed invention, and limitation is not made an invention that requires a combination of all features described in the embodiments, but the scope of the invention is defined by the appended claims. Furthermore, the same reference numerals are given to the same or similar configurations, and redundant description thereof is omitted.

A first embodiment of the present invention will be described.

In the first embodiment of the present invention, an image capturing system that controls shooting parameters in an image capturing apparatus based on user attribute information on an external image processing apparatus will be described.

<FIG> is a diagram showing a configuration example of an image capturing system including an image capturing apparatus according to a first embodiment of the present invention.

The image capturing system includes an image capturing apparatus <NUM> for capturing an image, a communication network <NUM>, and an external image processing apparatus <NUM> comprised of a server and the like. The image capturing apparatus <NUM> can communicate with the external image processing apparatus <NUM> via the network <NUM>.

Next, the functional configuration of the image capturing apparatus <NUM> will be described with reference to <FIG>.

An optical system <NUM> is composed of a lens group including a zoom lens and a focus lens, and forms a subject image on the imaging surface of an image sensing circuit <NUM>. The optical system <NUM> is provided with operation members (not shown) which are directly operated by a user to control the zoom position and focus position of the optical system <NUM>.

The image sensing circuit <NUM> is, for example, an image sensor such as a CCD or a CMOS sensor, and photoelectrically converts an optical image formed on the imaging surface of the image sensing circuit <NUM> by the optical system <NUM>. The obtained analog image signal is converted into digital image data by an A/D conversion circuit (not shown), and the image sensing circuit <NUM> outputs the digital image data as RAW image data. The RAW image data output from the image sensing circuit <NUM> is temporarily stored in a RAM <NUM>.

An image processing circuit <NUM> applies various image processing such as white balance adjustment, color interpolation, gamma processing, and NR processing to the RAW image data stored in the RAM <NUM>, and a resultant image of the image processing (for example, a JPEG image) is generated.

A control circuit <NUM> is, for example, a CPU, and reads a control program for each block included in the image capturing apparatus <NUM> from a ROM <NUM>, loads the control program into the RAM <NUM>, and executes the control program. In this way, the control circuit <NUM> controls the operation of each block included in the image capturing apparatus <NUM>. For example, based on the luminance information of a shooting scene and an EV chart described later, shooting parameters such as an aperture value of the optical system <NUM>, shutter speed of the image sensing circuit <NUM>, and ISO sensitivity are determined, and the operation of each block is controlled. Further, as will be described later, the control circuit <NUM> determines the shooting parameters by further using update information of the shooting parameters transmitted from the external image processing apparatus <NUM>.

The ROM <NUM> is an electrically erasable/recordable non-volatile memory, and stores an operation program for each block included in the image capturing apparatus <NUM>, as well as parameters required for the operation of each block. Also, as will be described later, user ID information regarding the use of an external image processing apparatus is recorded.

The RAM <NUM> is a rewritable volatile memory, and is used for loading programs executed by the control circuit <NUM>, etc., and temporarily storing data generated through the operation of each block provided in the image capturing apparatus <NUM>, and so forth.

A recording circuit <NUM> is a removable memory card or the like. The recording circuit <NUM> records image data processed by the image processing circuit <NUM> via the RAM <NUM>.

A display circuit <NUM> is a display device such as an LCD, and displays an image stored in the RAM <NUM>, an image recorded in the recording circuit <NUM>, an operation user interface for receiving an instruction from the user, and so forth.

An instruction input circuit <NUM> includes a touch panel and an operation buttons, and receives an instruction from the user. Further, the instruction input circuit <NUM> includes a shutter button (not shown), and the user can give an instruction for shooting by turning on a switch SW1 by half-pressing the shutter button, for example, and by turning on a switch SW2 by fully pressing the shutter button, for example.

A communication circuit <NUM> performs communication with the external image processing apparatus <NUM> via the network <NUM>, and transmits, for example, ID information representing a user attribute related to the use of the external image processing apparatus <NUM>, which will be described later, and RAW image data recorded on the recording circuit <NUM> to the external image processing apparatus <NUM>. Further, as will be described later, the communication circuit <NUM> receives information regarding the amount of change with respect to the shooting parameters from the external image processing apparatus <NUM>.

Next, the functional configuration of the external image processing apparatus <NUM> will be described with reference to a block diagram shown in <FIG>.

An external image processing circuit <NUM> applies various image processing such as white balance adjustment, color interpolation, gamma processing, and NR processing to the input RAW image data. It is assumed that at least a part of the image processing applied here is performed by using an algorithm different from the image processing applied in the image processing circuit <NUM> of the image capturing apparatus <NUM>. In the present embodiment, as an example, it will be explained that the algorithm of the NR processing is different from the algorithm used in the image processing circuit <NUM>, and algorithms and contents of the other image processing are common to the image capturing apparatus <NUM> and the external image processing apparatus <NUM>. Further, it will be described that a greater noise reduction effect can be achieved by the NR processing performed in the external image processing apparatus <NUM> than the NR processing performed in the image capturing apparatus <NUM>.

A user attribute determination circuit <NUM> determines a user attribute by referring to the user attribute information for the use of the external image processing apparatus <NUM> recorded in advance in association with ID information with respect to input ID information.

A shooting parameter conversion circuit <NUM> determines a change amount of the shooting parameter in the image capturing apparatus <NUM> based on the user attribute information determined by the user attribute determination circuit <NUM>.

An external communication circuit <NUM> communicates with the image capturing apparatus <NUM> via the network <NUM>, and receives, for example, RAW image data and ID information from the image capturing apparatus <NUM>. In addition, the external communication circuit <NUM> transmits information on shooting parameters determined by the shooting parameter conversion circuit <NUM> or the like to the image capturing apparatus <NUM>.

A ROM <NUM> is an electrically erasable/recordable non-volatile memory, and stores an operation program for each block included in the external image processing apparatus <NUM>, as well as parameters required for the operation of each block. Further, in the ROM <NUM>, the user attribute information regarding the use of the external image processing apparatus <NUM> is recorded in association with the ID information.

A RAM <NUM> is a rewritable volatile memory, and is used for loading a program executed by each part of the external image processing apparatus <NUM>, temporarily storing the generated data, and the like.

Next, an example of the user attribute information recorded in the external image processing apparatus <NUM> will be described with reference to <FIG>. In a user attribute information table <NUM>, a column <NUM> represents ID information of each user, and a column <NUM> represents information showing authorization to use image processing in the external image processing circuit <NUM>. For example, if user registration is required prior to use image processing in the external image processing circuit <NUM>, information on whether or not each user has performed user registration in advance is recorded.

Next, the operation of the image capturing system in the first embodiment will be described with reference to the flowcharts of <FIG> and <FIG>. <FIG> shows the processing in the image capturing apparatus <NUM>, and <FIG> shows the processing in the external image processing apparatus <NUM>.

First, in step S501, the image capturing apparatus <NUM> starts normal image shooting preparation. Specifically, when the user turns on the image capturing apparatus <NUM>, the control circuit <NUM> of the image capturing apparatus <NUM> acquires the brightness information of the shooting scene and determines the shooting parameters. In this embodiment, the case where the Av priority mode in which the user specifies and sets the aperture value (Av value) is selected will be described as an example.

The method of determining the shooting parameters performed here, particularly the method of determining ISO sensitivity, shutter speed, and aperture value will be described with reference to the Ev chart shown in <FIG>.

In <FIG>, a reference numeral <NUM> represents the luminance information (Bv value) of the shooting scene. A reference numeral <NUM> represents the shutter speed (Tv value), and Tv values used when the ISO sensitivity ranges from <NUM> to <NUM> are shown. A reference numeral <NUM> represents the aperture value (Av value), and Av values used when the ISO sensitivity ranges from <NUM> to <NUM> are shown.

When the ISO sensitivity is set to auto, the ISO sensitivity value which is predetermined by the designer for each Bv value based on the noise characteristics at each sensitivity and the prediction of the noise reduction effect after applying the NR processing is used. Here, a case where the Av value set by the user is <NUM> and the Bv value calculated by the control circuit <NUM> is <NUM> will be described as an example. Further, under the above conditions, it is assumed that the ISO sensitivity at the time of auto is designed in advance as <NUM>. In this case, the Tv value of <NUM>/<NUM> is determined as a shooting parameter. To sum up, the ISO sensitivity is <NUM>, the Tv value is <NUM>/<NUM>, and the Av value is <NUM>.

Regarding the ISO sensitivity setting when the ISO sensitivity is set to auto, increasing the ISO sensitivity and increasing the Tv value have the advantage of reducing the effects of camera shake and motion blur of the subject, but on the other hand, have the disadvantage of increasing image noise. For this trade-off, it is advisable to design the Ev chart so that the Tv value is set to be as fast as possible within the allowable range of the noise level in consideration of the noise reduction effect of the NR processing.

In step S502, it is determined whether or not an external cooperation shooting mode, which is a shooting mode that includes image processing by the external image processing apparatus <NUM>, is set by the user. If such mode is not set, the process proceeds to step S503 and a normal image shooting operation is performed. In step S503, an image is captured according to a user's shooting instruction as a normal image shooting operation. Here, after performing image shooting operation to capture RAW image data, a series of image processing is executed by the image processing circuit <NUM> and the process proceeds to step S511.

On the other hand, if the external cooperation shooting mode is set, the process proceeds to step S504, and a series of image shooting operation that uses image processing by the external image processing apparatus <NUM> is started. In step S504, ID information regarding the use of the external image processing apparatus <NUM> is transmitted from the communication circuit <NUM> of the image capturing apparatus <NUM> to the external image processing apparatus <NUM> via the network <NUM>, and the process proceeds to step S505.

In the external image processing apparatus <NUM>, the ID information is waited in step S520, and when the ID information is received, the process proceeds to step S521. In step S521, the user attribute determination circuit <NUM> determines whether or not the image processing in the external image processing apparatus <NUM> can be used by referring to the table shown in <FIG> with the received ID information used as a key. If the user attribute information indicates affirmative, the process proceeds to step S522 to acquire information indicating a change amount of the shooting parameter in the image capturing apparatus <NUM>. If it the user attribute information indicates negative, the process proceeds to step S523.

The change amounts of the shooting parameters are determined and stored in advance based on the difference in characteristics between the image processing in the image capturing apparatus <NUM> and the image processing in the external image processing circuit <NUM>. <FIG> shows an example of the change amounts of a shooting parameter.

The horizontal axis of the graph in <FIG> represents choices of the ISO sensitivity determined by the image capturing apparatus <NUM> in a normal image shooting operation. The vertical axis indicates the change amount of the ISO sensitivity in the external cooperation shooting mode, and shows that the shooting parameter is updated in the direction of increasing the ISO sensitivity by a predetermined amount at the time of high sensitivity than at the time of normal sensitivity. It means that, in the image shooting mode which uses the NR processing in the external image processing circuit <NUM>, it is controlled so that the image shooting is performed with higher ISO sensitivity than usual. By this change, the shutter speed (Tv value) can be set faster by the amount that the ISO sensitivity is increased, and the influence of camera shake and motion blur of the subject can be suppressed.

On the other hand, in step S523, since the image processing in the external image processing apparatus <NUM> cannot be used, it is determined to transmit that the image processing in the external image processing apparatus <NUM> cannot be used.

In step S524, the information on the change amount of the shooting parameter shown in <FIG> determined in step S522 or the fact that the image processing in the external image processing apparatus <NUM> is not available which is determined in step S523 is transmitted to the camera via the network <NUM>.

The image capturing apparatus <NUM> waits in step S505 until it receives the information on the change amount of the shooting parameter or the fact that the image processing in the external image processing apparatus <NUM> cannot be used. Then, in step S506, when the received content is not information on the change amount of the shooting parameter, that is, in a case where the image processing in the external image processing apparatus <NUM> cannot be used, the process proceeds to step S503 to perform a normal image shooting operation.

On the other hand, if the received content is information on the change amount of the shooting parameter, the process proceeds to step S507, and the shooting parameters are updated based on the received information. For example, in the Ev chart shown in <FIG>, when the shutter speed (Tv value) selected in the normal image shooting operation is the Tv value <NUM>/<NUM>, the Tv value <NUM>/<NUM>, which is a value when the ISO sensitivity is increased by one step, is newly selected. That is, the shooting parameters in the normal image shooting operation are ISO sensitivity <NUM>, Tv value <NUM>/<NUM>, and Av value <NUM>, whereas the shooting parameters in the external cooperation shooting mode are ISO sensitivity <NUM>, Tv value <NUM>/<NUM>, and Av value <NUM>.

In step S508, the image capturing apparatus <NUM> captures an image using the updated shooting parameters. Here, the processes up to which the RAW image data output from the image sensing circuit <NUM> is recorded in the recording circuit <NUM> are performed.

Next, in step S509, the image capturing apparatus <NUM> transmits the recorded RAW image data to the external image processing apparatus <NUM> via the network <NUM>.

The external image processing apparatus <NUM> waits until the RAW image data is received from the image capturing apparatus <NUM> in step S525, and when the RAW image data is received, in step S526, the received RAW image data undergoes image processing by the external image processing circuit <NUM>, and image data is generated.

In step S527, the external image processing apparatus <NUM> transmits the generated image data to the image capturing apparatus <NUM> via the network <NUM>. Note that the external image processing apparatus <NUM> may record the generated image data on a recording medium (not shown) instead of transmitting it to the image capturing apparatus <NUM> so that the user can freely access the recorded image data.

The image capturing apparatus <NUM> waits until the processed image data is received from the external image processing apparatus <NUM> in step S510, and when the image data is received, the received image data is recorded in the recording circuit <NUM> in step S511.

As described above, according to the first embodiment, when image processing using an external image processing apparatus is performed, suitable shooting parameters can be determined by reflecting the characteristics of image processing to be performed in the external image processing apparatus, thereby it is possible to improve the image quality of a captured image. Further, even if the external image processing apparatus is not used or cannot be used, shooting parameters suitable for the characteristics of image processing to be performed in the image processing apparatus can be determined.

In the present embodiment, the case where the NR processing is applied by an external image processing apparatus has been described as an example, but the content of the image processing in the present invention is not limited to this. For example, aberration correction may be performed to correct the aberration that occurs in a case where the aperture of the lens is set near the full-open state. In this case, if the aberration is corrected in the external image processing apparatus, the aperture of the lens may be controlled to be changed toward the open side than usual. By doing so, even if the shooting scene is dark, a sufficient amount of light can be received because the aperture is changed toward the open side, and an image with a high resolution can be captured. That is, any image processing may be applied as long as the image processing having different characteristics from those of the image processing performed in the image processing apparatus is applied in the external image processing apparatus.

Further, in the present embodiment, the case of controlling the ISO sensitivity in the Av priority image shooting mode has been described as an example of controlling the shooting parameters, but the method of controlling the shooting parameters in the present invention is not limited to this. For example, in an image shooting mode with an ISO sensitivity auto mode, if the upper limit of the ISO sensitivity to be used is set, the shooting parameters may be controlled so as to raise the upper limit.

In the above description, it is explained that, in a case where it is determined that image processing can be used based on the user attributes, the external image processing apparatus <NUM> determines the change amount of the shooting parameter as shown in <FIG> and notifies the change amount to the image capturing apparatus <NUM>, however, the present invention is not limited to this. The shooting parameters may be sent from the image capturing apparatus <NUM> to the external image processing apparatus <NUM>, and if image processing can be used, the external image processing apparatus <NUM> may change the sent shooting parameters and transmit the changed shooting parameters to the image capturing apparatus <NUM>. Alternatively, only the change amount of the transmitted shooting parameter may be transmitted to the image capturing apparatus <NUM>.

Further, in the present embodiment, it is explained that after an image is captured, obtained RAW image signal is transmitted from the image capturing apparatus <NUM> to the external image processing apparatus <NUM>, and the RAW image signal undergoes the image processing in the external image processing apparatus <NUM>. However, the timing of applying the image processing to the RAW image signal in the present invention is not limited to this. For example, only the transmission of user attribute information regarding the use of the external image processing apparatus <NUM> and the processing related to updating of the shooting parameters may be performed at the time of image shooting, and the image processing in the external image processing apparatus <NUM> may be performed after the image shooting. For example, the RAW image recorded on the recording medium in the image capturing apparatus <NUM> may be transferred onto a user's PC and then transmitted from the user's PC to the external image processing apparatus <NUM>, where image processing is applied.

Further, in the present embodiment, the case where the image capturing apparatus <NUM> and the external image processing apparatus <NUM> transmit and receive information via the network <NUM> has been described as an example, however, transmission and reception between the image capturing apparatus <NUM> and the external processing apparatus <NUM> is not limited to this. For example, a configuration in which an edge device such as a smartphone is used as the external image processing apparatus <NUM>, and the image capturing apparatus <NUM> and the edge device directly communicate with each other via wired or wireless communication may be used.

Further, instead of a RAW image, an image (for example, a JPEG image) after the image processing is applied by the image capturing apparatus <NUM> may be transmitted to the external image processing apparatus <NUM>. In this case, the external image processing apparatus <NUM> applies image processing such as NR processing to the transmitted image (for example, a JPEG image).

Further, in the present embodiment, a case where the user attribute determination circuit <NUM> for determining the user attribute information related to the use of the external image processing apparatus <NUM> and the external image processing circuit <NUM> that applies the image processing are configured in the same apparatus is explained as an example. However, the configuration of the external image processing apparatus in the present invention is not limited to this. For example, the user attribute determination circuit may be configured to communicate with the image capturing apparatus <NUM> via a network, and the external image processing circuit <NUM> may be configured as a software executed on a PC at the user's home.

Further, in the present embodiment, updating of the shooting parameter determined by the external image processing apparatus <NUM> is automatically applied on the image capturing apparatus <NUM> and the updated shooting parameters are used for image shooting as an example. However, the control method of shooting parameters is not limited to this. For example, the change amount of the shooting parameter determined by the external image processing apparatus <NUM> may be notified to the user as a recommended value on the display circuit of the image capturing apparatus <NUM>, and the shooting parameters may be updated depending upon the user's selection. That is, any method of using information on the converted shooting parameters may be used as long as the method is to perform the processing of converting the user attribute information related to the use of the external image processing apparatus <NUM> to information on the shooting parameters.

Next, a second embodiment not forming part of the present invention will be described. Since the configuration of the image capturing system in the second embodiment is the same as that described with reference to <FIG>, the description thereof will be omitted here.

In the first embodiment described above, a case where the change amounts of the shooting parameter are determined based on the user attribute information regarding the use of the external image processing apparatus <NUM> has been described. By contrast, in the second embodiment, a case where the shooting parameters are changed based on the shooting information regarding the shooting of an image by the image capturing apparatus <NUM> will be described.

As in the case described in the first embodiment, even if the NR processing in the external image processing apparatus <NUM> has a better noise reduction effect, there are cases where the difference in the noise reduction effect performed in the image capturing apparatus <NUM> and the external image processing apparatus <NUM> is small depending on a shooting scene and a subject. In such a case, it is necessary to use information on the shooting scene and a captured image in order to appropriately determine the change amounts of the shooting parameters.

Next, the image shooting operation in the second embodiment will be described with reference to <FIG> and <FIG>. <FIG> shows the processing in the image capturing apparatus <NUM>, and <FIG> shows the processing in the external image processing apparatus <NUM>. Further, in the processes shown in <FIG> and <FIG>, the same processes as those described in <FIG> and <FIG> are given the same step numbers, and the description thereof will be omitted as appropriate.

In step S804, the image capturing apparatus <NUM> captures an image during a preparatory image shooting period, acquires RAW image data, and applies image processing to the acquired RAW image data in the image processing circuit <NUM> to generate image data.

In step S805, the image capturing apparatus <NUM> transmits the RAW image data and the image data which has undergone the image processing acquired in step S804 to the external image processing apparatus <NUM> as shooting information.

In step S820, the external image processing circuit <NUM> waits for the reception of the shooting information, and when it receives the image information, the process proceeds to step S821 and the external image processing circuit <NUM> applies NR processing to the received RAW image data.

In step S822, the shooting parameter conversion circuit <NUM> determines a change amount of the shooting parameter. Specifically, the shooting parameter conversion circuit <NUM> compares the degrees of noise between the image data undergone the image processing transmitted from the image capturing apparatus <NUM> and the image data undergone external image processing generated by the external image processing circuit <NUM> (between image signals). For example, when the difference value between the two images is calculated, the difference value indicates the difference in noise reduction effect between the image capturing apparatus <NUM> and the external image processing apparatus <NUM>. Therefore, the degrees of noise can be compared by using the amplitude of the signal of the difference value as the noise evaluation value.

The shooting parameter conversion circuit <NUM> determines the update content of the shooting parameters based on the calculated noise evaluation value and the characteristics shown in <FIG>. In <FIG>, the horizontal axis represents the calculated noise evaluation value, and the vertical axis represents the change amount of the ISO sensitivity by the number of steps. For example, if the calculated noise evaluation value is larger than a value shown by a reference numeral <NUM> in the figure, the change amount of the ISO sensitivity is determined as one step. In this case, the ISO sensitivity can be increased and the shutter speed can be set faster than in the case of normal image shooting operation, so it is possible to reduce the effects of camera shake and subject blur, thereby it is possible to improve the image quality. On the other hand, if the calculated noise evaluation value is smaller than a value shown by a reference numeral <NUM> in the figure, it is determined that the ISO sensitivity is not changed.

Then, in step S823, in a case where the change amount of the shooting parameter is determined in step S822, the external image processing circuit <NUM> transmits the change amount of the shooting parameter to the image capturing apparatus <NUM>. On the contrary, in a case where it is determined not to change the shooting parameter in step S822, the external image processing circuit <NUM> transmits the notice of not changing the shooting parameter to the image capturing apparatus <NUM>.

In step S806, the image capturing apparatus <NUM> waits for the information regarding the change amount of the shooting parameter, and when it receives the information regarding the change amount of the shooting parameter, the process proceeds to step S507, and thereafter the image capturing apparatus <NUM> performs the processes described with reference to <FIG>. On the other hand, when the image capturing apparatus receives the notice of not changing the shooting parameter, the process proceeds to step S503, and thereafter the image capturing apparatus <NUM> performs the processes described with reference to <FIG>.

As described above, according to the second embodiment, it is possible to determine shooting parameters that reflect the characteristics of image processing to be performed in the external image processing apparatus for each shooting scene.

Note that the second embodiment is explained by using a case where the RAW image data obtained during preparatory image shooing and the image data which has undergone the image processing in the image capturing apparatus <NUM> are transmitted to the external image processing apparatus <NUM> as shooting information, and are used to determine the change amount of the shooting parameter, as an example. However, the present invention does not limit the image data transmitted from the image capturing apparatus <NUM> to the external image processing apparatus <NUM> to these. For example, information on the brightness of the shooting scene, information on the type of subject, and information on the characteristics of edges and texture components contained in the subject may be transmitted as the shooting information, and a result of image processing applied by an external image processing apparatus may be estimated based on the shooting information.

Further, in the present embodiment, the case where both the RAW image data and the image processing resultant image to which the image processing by the image capturing apparatus <NUM> is applied is transmitted has been described, however, only a RAW image signal may be transmitted to the external image processing apparatus, and the external image processing apparatus <NUM> may apply the same image processing as the image capturing apparatus <NUM> to the RAW image signal and the resultant image maybe used as the image processing resultant image.

Further, in the present embodiment, the configuration in which the external image processing apparatus <NUM> determines the change amount of the shooting parameter of the image capturing apparatus <NUM> has been described as an example, but the present invention is not limited to this. For example, when the image capturing apparatus <NUM> can confirm that the image processing by the external image processing apparatus <NUM> will be used, the image capturing apparatus <NUM> may change the shooting parameters according to a predetermined rule. Specifically, when it is confirmed that the image processing by the external image processing apparatus <NUM> will be used, the image capturing apparatus <NUM> may perform processing such that the Ev chart is changed to that with the ISO sensitivity being increased by one step, the upper limit of the ISO sensitivity that can be set being increased by one step, and so on. If the NR processing by the external image processing apparatus <NUM> can be used, the ISO sensitivity of the shooting parameters may be increased, and if the aberration correction processing can be used, the aperture of the shooting parameters may be shifted to the open side. Further, if both the NR processing and the aberration correction processing by the external image processing apparatus <NUM> can be used, the ISO sensitivity may be increased and the aperture may be shifted to the open side. That is, the shooting parameters may be changed according to the type of image processing used in the external image processing apparatus <NUM>.

Various methods are conceivable as a method for the image capturing apparatus <NUM> to confirm whether to use the image processing by the external image processing apparatus <NUM>. For example, a method that the image capturing apparatus <NUM> communicates with the external image processing apparatus <NUM> to authenticate the user, and a method that causes the user to enter an authentication code obtained from the external image processing apparatus <NUM> into the image capturing apparatus <NUM> are conceivable. Alternatively, a configuration to cause the user to select whether to use image processing by an external device on the setting menu of the image capturing apparatus <NUM> may be used. With such the configuration, since the image capturing apparatus <NUM> itself changes the shooting parameters, it is not always necessary to provide the shooting parameter conversion circuit <NUM> in the external image processing apparatus <NUM>.

Further, in the present embodiment, the case where the image capturing apparatus <NUM> and the external image processing apparatus <NUM> are separately configured has been described as an example, but the configuration of the image capturing apparatus <NUM> in the present invention is limited to this. For example, an image capturing apparatus <NUM> may be provided with a plurality of image processing circuits at least some whose processing contents are different from each other. In this case, the shooting parameters are set based on the characteristics of the image processing circuit used during normal image shooting operation, and when another image processing circuit is to be used, the shooting parameters may be updated to the shooting parameters set based on the characteristics of image processing of the image processing circuit to be used. By doing so, even in a case where a plurality of types of image processing with different characteristics are selectively used according to their characteristics, it is possible to determine the shooting parameters depending upon the characteristics of the respective types of image processing.

Further, in the present embodiment, the case where the RAW image data is transmitted to the external image processing apparatus <NUM> during the preparatory image shooting period when the image shooting operation is started has been described as an example, but the present invention does not limit the timing of transmitting the RAW image data to this. For example, the transmission of shooting information and the update of shooting parameters may be performed in a case where it is detected during the preparatory image shooting period that the shooting scene or a subject has changed significantly, or that the shooting parameters to be used change significantly. In addition, the transmission of shooting information and the update of shooting parameters may be performed in a case where ISO sensitivity equal to or higher than a predetermined threshold is set or in a case where it is predicted that desirable image quality cannot be achieved when normal image processing in an image capturing apparatus is applied such as a case where camera shake or motion blur is detected in the captured image.

Claim 1:
An image capturing apparatus (<NUM>) comprising:
image sensing means (<NUM>) including an image sensor and configured to capture an image by photoelectric converting an optical image formed on an imaging surface and output an image signal;
setting means (<NUM>) configured to set values for shooting parameters to be used at a time of capturing the image by the image sensing means (<NUM>);
communication means (<NUM>) configured to perform transmission and reception of information with an external image processing apparatus (<NUM>);
characterized by
image processing means (<NUM>) configured to perform image processing using different algorithm from that of the image processing in the external image processing apparatus (<NUM>);
wherein the communication means (<NUM>) is further configured to receive information indicating whether or not it is possible to apply image processing to the image signal in the external image processing apparatus (<NUM>) from the external image processing apparatus (<NUM>);
wherein the setting means (<NUM>) is configured to set different values for the same shooting parameters to be used at the time of capturing the image by the image sensing means (<NUM>) between a case where it is possible to apply image processing on the image signal by the external image processing apparatus (<NUM>) and a case where it is not possible to apply image processing on the image signal by the external image processing apparatus (<NUM>),
wherein the setting means (<NUM>) is configured to set the values for shooting parameters based on information obtained from the external image processing apparatus (<NUM>) via the communication means (<NUM>) in a case where it is possible to apply the image processing to the image signal in the external image processing apparatus (<NUM>).