Patent Publication Number: US-2023164431-A1

Title: Image capturing apparatus, processing system, and control method

Description:
CROSS REFERENCE TO PRIORITY APPLICATION 
     This application claims the benefit of Japanese Patent Application No. 2021-191435, filed Nov. 25, 2021, which is hereby incorporated by reference herein in its entirety. 
     FIELD OF THE INVENTION 
     The present invention relates to a technique of distributing processing. 
     DESCRIPTION OF THE RELATED ART 
     In recent years, solutions for performing face authentication using an image captured by a monitoring camera and managing access have proliferated. Since the processing load of image processing such as face authentication is relatively high, a configuration is conventionally used, in which the monitoring camera transfers an obtained video to a high-performance arithmetic apparatus (a PC or a server) in a remote site, and the arithmetic apparatus performs image processing. However, along with the improvement of the processing capability of a recent mobile arithmetic apparatus, image processing can be performed on the monitoring camera side (locally). The processing on the monitoring camera side can be executed by, for example, an arithmetic apparatus arranged in the camera body. The processing can also be executed by an arithmetic apparatus in a detachable device connected to the camera body. If image processing is performed on the monitoring camera side, a load of image processing in the server or a communication load in a communication network can be reduced. 
     Japanese Patent Laid-Open No. 7-184098 describes a technique of providing an extension function by connecting a detachable device to an image capturing apparatus. Japanese Patent Laid-Open No. 2019-219804 describes a technique of mounting a detachable device on an image capturing apparatus and switching processing between the detachable device and the image capturing apparatus based on an execution instruction. 
     In the above-described patent literatures, however, although extension of processing in the detachable device is described, an efficient use method including processing distribution with server processing is not examined. In general, as the characteristic of the image capturing apparatus and the detachable device, hardware performance is lower than a PC or a server. For this reason, the techniques described in the above-described patent literatures cannot optimize processing in the entire system. 
     SUMMARY OF THE INVENTION 
     According to one aspect of the present invention, an image capturing apparatus in which a detachable device including a processing unit configured to execute analysis processing for image data obtained by image capturing is mounted, comprises: a communication unit configured to communicate with an external processing apparatus capable of executing the analysis processing for the image data; a processor; and a memory containing instructions that, when executed by the processor, cause the processor to function as: a load obtaining unit configured to obtain load information concerning a load state in the external processing apparatus via the communication unit; and a determination unit configured to determine, based on the load information, which one of the processing unit and the external processing apparatus is to be used to perform the analysis processing. 
     The present invention enables optimization of the processing speed of an entire system. 
     Further features of the present invention will become apparent from the following description of exemplary embodiments (with reference to the attached drawings). 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       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. 
         FIG.  1    is a block diagram showing an example of a system configuration; 
         FIG.  2    is a block diagram showing an example of the hardware configuration of an image capturing apparatus; 
         FIG.  3 A  is a block diagram showing an example of the functional configuration of the image capturing apparatus; 
         FIG.  3 B  is a block diagram showing an example of the functional configuration of an analysis unit; 
         FIG.  4    is a block diagram showing an example of the hardware configuration of a detachable device; 
         FIG.  5 A  is a block diagram showing an example of the functional configuration of the detachable device; 
         FIG.  5 B  is a block diagram showing an example of the functional configuration of an analysis unit; 
         FIG.  6    is a block diagram showing an example of the hardware configuration of a server; 
         FIG.  7 A  is a block diagram showing an example of the functional configuration of the server; 
         FIG.  7 B  is a block diagram showing an example of the functional configuration of an analysis unit; 
         FIG.  8    is a flowchart showing an example of the procedure of processing executed by the system; 
         FIGS.  9 A- 9 C  are flowcharts showing an example of the procedure of face authentication processing and electric lock unlocking processing; 
         FIG.  10 A  is a view showing an example of tables used for image processing execution place judgement processing; 
         FIG.  10 B  is a view showing an example of a table used for image processing execution place judgement processing; 
         FIG.  11    is a flowchart showing an example of the procedure of image processing execution place judgement processing; 
         FIG.  12    is a view showing an example of the load/processing time of each device; 
         FIG.  13    is a flowchart showing another example of the procedure of image processing execution place judgement processing; 
         FIG.  14    is a view showing another example of tables for defining the capability of each device; 
         FIGS.  15 A- 15 C  are flowcharts showing another example of the procedure of face authentication processing and electric lock unlocking processing; and 
         FIGS.  16 A- 16 C  are flowcharts showing still another example of the procedure of face authentication processing and electric lock unlocking processing. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Hereinafter, embodiments will be described in detail with reference to the attached drawings. Note, the following embodiments are not intended to limit the scope of the claimed invention. Multiple features are described in the embodiments, but limitation is not made to an invention that requires all such features, and multiple such features may be combined as appropriate. Furthermore, in the attached drawings, the same reference numerals are given to the same or similar configurations, and redundant description thereof is omitted. 
     First Embodiment 
     As the first embodiment of an information processing apparatus according to the present invention, an image analysis system  101  including an image capturing apparatus  110 , a detachable device  100 , and a server  130  will now be described below as an example. 
     System Configuration 
       FIG.  1    shows an example of the configuration of the image analysis system  101  according to this embodiment. As an example, a case in which this system is an access management system will be described below. However, the present invention is not limited to this, and the following argument can be applied to an arbitrary processing system for analyzing an image and performing predetermined information output. This system is configured to include image capturing apparatuses  110   a  to  110   d , a network  120 , the server  130  that is an external processing apparatus, and an I/O module  140 . Note that the image capturing apparatuses  110   a  to  110   d  each include a slot to/from which a device capable of recording, for example, a captured image can be attached/detached, and when the detachable devices  100   a  to  100   d  are inserted into the slots, the image capturing apparatuses  110   a  to  110   d  are connected to the detachable devices  100   a  to  100   d . Also, an access controller  150 , a card reader  160 , and an electric lock  170  are connected to the I/O module  140 . An ID card or the like is put over the card reader  160 , thereby performing ID authentication by the card reader. Note that the detachable devices  100   a  to  100   d  will be referred to as “detachable devices  100 ”, and the image capturing apparatuses  110   a  to  110   d  will be referred to as “image capturing apparatuses  110 ” hereinafter. 
     The detachable device  100  is an arithmetic device attachable/detachable to/from the image capturing apparatus  110 . As an example, the detachable device  100  is a device with a predetermined processing circuit mounted in an SD card. The detachable device  100  is configured to be inserted as a whole into the image capturing apparatus  110  in a form of, for example, an SD card, and can therefore be configured to be connectable to the image capturing apparatus  110  without making any portion project from the image capturing apparatus  110 . This can prevent the detachable device  100  from interfering with an obstacle such as a wiring and raise the convenience when using the device. In addition, since an SD card slot is prepared in a lot of existing image capturing apparatuses  110  such as a network camera, the detachable device  100  can provide an extension function to the existing image capturing apparatus  110 . Note that other than the form of an SD card, the detachable device  100  may be configured to be mounted in the image capturing apparatus  110  via an arbitrary interface used when mounting a storage device capable of storing an image captured by at least the image capturing apparatus  110 . For example, the detachable device  100  may include a USB (Universal Serial Bus) interface, and may be configured to be mounted in a USB socket of the image capturing apparatus  110 . The predetermined processing circuit is implemented by, for example, an FPGA (Field Programmable Gate Array) programmed to execute predetermined processing but may be implemented in another form. 
     The image capturing apparatus  110  is an image capturing apparatus such as a network camera. In this embodiment, the image capturing apparatus  110  incorporates an arithmetic apparatus (information processing apparatus) capable of processing a video but is not limited to this. For example, an external computer such as an information processing apparatus (PC: Personal Computer) connected to the image capturing apparatus  110  may exist, and the combination may be handled as the image capturing apparatus  110 . Additionally, in this embodiment, the detachable devices  100  are mounted in all the image capturing apparatuses  110 . Note that  FIG.  1    shows four image capturing apparatuses  110 , and the detachable devices mounted in these. The number of combinations of devices may be three or less, or five or more. When the detachable device  100  having an image analysis processing function is mounted in the image capturing apparatus  110 , video processing can be executed on the side of the image capturing apparatus  110  even if the image capturing apparatus  110  does not have the image analysis processing function. Also, in a form in which an arithmetic apparatus for video processing is arranged in the image capturing apparatus  110 , as in this embodiment, image processing executable on the side of the image capturing apparatus  110  can be diversified/sophisticated by mounting the detachable device  100  including an arithmetic apparatus in the image capturing apparatus  110 . 
     The server  130  is formed by a computer such as a PC and has an image analysis processing function. In addition, the server  130  is an apparatus that performs acceptance of input from a user and output of information (for example, display of information) to the user. 
     The image capturing apparatuses  110  and the server  130  are communicably connected via the network  120 . The network  120  is configured to include a plurality of routers, switches, cables, and the like, which satisfy the communication standard of, for example, Ethernet®. In this embodiment, the network  120  can be an arbitrary network that enables communication between the image capturing apparatus  110  and the server  130 , and can be constructed by an arbitrary scale and configuration and a communication standard to comply with. For example, the network  120  can be the Internet, a wired LAN (Local Area Network), a wireless LAN, a WAN (Wide Area Network), or the like. The network  120  can be configured such that, for example, communication by a communication protocol complying with the ONVIF (Open Network Video Interface Forum) standard is possible. However, the network  120  is not limited to this and may be configured such that, for example, communication by another communication protocol such as a unique communication protocol is possible. 
     The I/O module  140  is communicably connected to the image capturing apparatus  110  and the server  130  via the network  120 . The I/O module  140  receives an HTTP event (for example, an unlocking event) from the image capturing apparatus  110  or the server  130 , and transmits an electrical control signal to the access controller  150  via an electric wire  180 . 
     The access controller  150  is connected to the I/O module  140 , the card reader  160 , and the electric lock  170  via the electric wires  180 . The access controller  150  has a card collation/discrimination function, performs card collation/discrimination using card information read by the card reader  160 , and controls locking and unlocking of the electric lock  170 . Also, the access controller  150  receives an electrical control signal from the I/O module  140 , and controls locking and unlocking of the electric lock  170 . The card reader  160  is a reader for a magnetic card or a noncontact IC card, and transmits read information to the access controller  150 . The electric lock  170  is a lock whose locking/unlocking is controlled by electric control. 
     Apparatus Configuration 
     Configuration of Image Capturing Apparatus 
     The configuration of the image capturing apparatus  110  will be described next.  FIG.  2    is a block diagram showing an example of the hardware configuration of the image capturing apparatus  110 . As the hardware configuration, the image capturing apparatus  110  includes, for example, an image capturing unit  201 , an image processing unit  202 , an arithmetic processing unit  203 , a distribution unit  204 , and an SD I/F unit  205 . Note that I/F is an abbreviation of interface. 
     The image capturing unit  201  is configured to include a lens portion configured to form an image of light, and an image capturing element that performs analog signal conversion according to the formed image of light. The lens portion has a zoom function of adjusting an angle of view, a stop function of adjusting a light amount, and the like. The image capturing element has a gain function of adjusting sensitivity when converting light into an analog signal. These functions are adjusted based on set values notified from the image processing unit  202 . The analog signal obtained by the image capturing unit  201  is converted into a digital signal by an analog-to-digital conversion circuit and transferred to the image processing unit  202  as an image signal. 
     The image processing unit  202  is configured to include an image processing engine, and peripheral devices thereof. The peripheral devices include, for example, a RAM (Random Access Memory), the drivers of I/Fs, and the like. The image processing unit  202  performs, for example, image processing such as development processing, filter processing, sensor correction, and noise removal for the image signal obtained from the image capturing unit  201 , thereby generating image data. The image processing unit  202  can also transmit set values to the lens portion and the image capturing element and execute exposure adjustment to obtain an appropriately exposed image. The image data generated by the image processing unit  202  is transferred to the arithmetic processing unit  203 . 
     The arithmetic processing unit  203  is formed by at least one processor such as a CPU or an MPU, memories such as a RAM and a ROM, the drivers of I/Fs, and the like. Note that CPU is the acronym of Central Processing Unit, MPU is the acronym of Micro Processing Unit, RAM is the acronym of Random Access Memory, and ROM is the acronym of Read Only Memory. In an example, the arithmetic processing unit  203  can determine allocation concerning which one of the image capturing apparatus  110 , the detachable device  100 , and the server  130  should execute each portion of processing to be executed in the above-described system, and execute processing corresponding to the allocation. Details of processing contents and processing allocation will be described later. The image received from the image processing unit  202  or the processing result of the arithmetic processing unit  203  is transferred to the distribution unit  204  or the SD I/F unit  205 . 
     The distribution unit  204  is configured to include a network distribution engine and, for example, peripheral devices such as a RAM and an ETH PHY module. The ETH PHY module is a module that executes processing of the physical (PHY) layer of Ethernet. The distribution unit  204  converts the image data or the data of the processing result obtained from the arithmetic processing unit  203  into a format distributable to the network  120 , and outputs the converted data to the network  120 . The SD I/F unit  205  is an interface portion used to connect the detachable device  100 , and is configured to include, for example, a power supply, and a mounting part such as an attaching/detaching socket used to attach/detach the detachable device  100 . Here, the SD I/F unit  205  is configured in accordance with the SD standard formulated by the SD Association. Communication between the detachable device  100  and the image capturing apparatus  110 , such as transfer of an image obtained from the arithmetic processing unit  203  to the detachable device  100  or data obtaining from the detachable device  100 , is performed via the SD I/F unit  205 . 
       FIG.  3 A  shows an example of the functional configuration of the image capturing apparatus  110 . Also,  FIG.  3 B  shows the detailed configuration of an analysis unit  305 . The image capturing apparatus  110  includes, as its functions, for example, an image capturing control unit  301 , a signal processing unit  302 , a storage unit  303 , a control unit  304 , the analysis unit  305 , a device communication unit  306 , and a network communication unit  307 . 
     The image capturing control unit  301  executes control of capturing the peripheral environment via the image capturing unit  201 . The signal processing unit  302  performs predetermined processing for the image captured by the image capturing control unit  301 , thereby generating data of the captured image. The data of the captured image will simply be referred to as the “captured image” hereinafter. The signal processing unit  302 , for example, encodes the image captured by the image capturing control unit  301 . The signal processing unit  302  performs encoding for a still image using, for example, an encoding method such as JPEG (Joint Photographic Experts Group). The signal processing unit  302  performs encoding for a moving image using an encoding method such as H.264/MPEG-4 AVC (to be referred to as “H.264” hereinafter) or HEVC (High Efficiency Video Coding). The signal processing unit  302  may encode an image using an encoding method selected by the user from a plurality of encoding methods set in advance via, for example, an operation unit (not shown) of the image capturing apparatus  110 . 
     The storage unit  303  stores a list of analysis processing executable by the analysis unit  305 . The storage unit  303  also stores a result of analysis processing to be described later. The control unit  304  controls the signal processing unit  302 , the storage unit  303 , the analysis unit  305 , the device communication unit  306 , and the network communication unit  307  to execute predetermined processing. 
     The analysis unit  305  selectively executes at least one of pre-analysis processing  308 , face detection processing  309 , face characteristic extraction processing  310 , face characteristic collation processing  311 , and post-analysis processing  312  to be described later for a captured image. 
     The pre-analysis processing  308  is processing to be executed for a captured image before face detection processing to be described later is executed. In the pre-analysis processing  308  according to this embodiment, as an example, a captured image is divided to create divided images. 
     The face detection processing  309  is processing of performing face detection for the divided image obtained by the pre-analysis processing  308  and outputting face position region information representing the region of a detected face and a face likelihood that is the likelihood of a face (face likelihood). The face detection processing  309  can be processing configured to output the position of a face in the divided image using, for example, a machine learning model. 
     The face characteristic extraction processing  310  is processing of using the face position region information output from the face detection processing  309 , cropping the face image region from the divided image, and extracting a face characteristic. The extracted face characteristic is output as a multidimensional vector. 
     The face characteristic collation processing  311  is processing of performing collation between a face characteristic list for a plurality of face images registered in an image registration unit to be described later, which the image capturing apparatus  110  obtains from the server  130  in advance, and a face characteristic extracted by the face characteristic extraction processing  310 . In the face characteristic collation processing  311  according to this embodiment, as an example, the distance between a face characteristic (multidimensional vector) of a registered image and an extracted face characteristic (multidimensional vector) is calculated, and if the distance is equal to or less than a predetermined threshold, collation is OK. If the distance is less than the predetermined threshold, collation is NG. 
     The post-analysis processing  312  is processing of filtering likelihoods (face likelihoods) detected by the face detection processing  309  using a predetermined threshold and integrating overlapping face position regions based on the face likelihood value. A list of combinations of face position region information and face likelihoods after the post-analysis processing  312  is performed will be referred to as metadata hereinafter. 
     The device communication unit  306  performs communication with the detachable device  100 . The device communication unit  306  converts input data into a format processible by the detachable device  100 , and transmits data obtained by the conversion to the detachable device  100 . In addition, the device communication unit  306  receives data from the detachable device  100 , and converts the received data into a format processible by the image capturing apparatus  110 . In this embodiment, as the conversion processing, the device communication unit  306  executes processing of converting a decimal between a floating point format and a fixed point format. However, the present invention is not limited to this, and another processing may be executed by the device communication unit  306 . Additionally, in this embodiment, the device communication unit  306  transmits a command sequence determined in advance within the range of the SD standard to the detachable device  100 , and receives a response from the detachable device  100 , thereby performing communication with the detachable device  100 . The network communication unit  307  performs communication with the server  130  via the network  120 . 
     A server load obtaining unit  313  obtains load information representing the load state of the server from the server  130  via the network communication unit  307  (load obtaining). Based on the server load state and the image processing capability of each device to be described later, an image processing control unit  314  judges whether each image processing should be performed by the image capturing apparatus  110 , the detachable device  100 , or the server  130 . 
     Configuration of Detachable Device 
       FIG.  4    is a block diagram showing an example of the hardware configuration of the detachable device  100 . As an example, the detachable device  100  is configured to include an I/F unit  401 , an FPGA  402 , an SD controller  403 , and a storage unit  404 . The detachable device  100  is formed into a shape that can be inserted/removed into/from the attaching/detaching socket of the SD I/F unit  205  provided in the image capturing apparatus  110 , that is, a shape complying with the SD standard. 
     The I/F unit  401  is an interface portion used to connect an apparatus such as the image capturing apparatus  110  and the detachable device  100 . The I/F unit  401  is configured to include, for example, an electrical contact terminal that receives supply of power from the image capturing apparatus  110  and generates and distributes a power supply to be used in the detachable device  100 , and the like. Concerning items defined in the SD standard, the I/F unit  401  complies with that, like the SD I/F unit  205  of the image capturing apparatus  110 . Reception of images and setting data from the image capturing apparatus  110  and transmission of data from the FPGA  402  to the image capturing apparatus  110  are executed via the I/F unit  401 . 
     The FPGA  402  is configured to include an input/output control unit  410 , a processing switching unit  411 , and an arithmetic processing unit  412 . The FPGA  402  is a kind of semiconductor device capable of repetitively reconstructing an internal logic circuit structure. By processing implemented by the FPGA  402 , a processing function can be added to the apparatus in which the detachable device  100  is mounted. Additionally, since the logic circuit structure can be changed later by the reconstruction function of the FPGA  402 , when the detachable device  100  is mounted in, for example, an apparatus in a field of a quickly advancing technology, appropriate processing can be executed in the apparatus at an appropriate timing. Note that in this embodiment, an example in which an FPGA is used will be described. However, for example, a general-purpose ASIC or a dedicated LSI may be used if processing to be described later can be executed. The FPGA  402  is activated by writing, from a dedicated I/F, setting data including the information of a logic circuit structure to be generated or reading out the setting data from the dedicated I/F. In this embodiment, the setting data is held in the storage unit  404 . When powered on, the FPGA  402  reads out the setting data from the storage unit  404  and generates and activates a logic circuit. However, the present invention is not limited to this. For example, the image capturing apparatus  110  may write the setting data in the FPGA  402  via the I/F unit  401  by implementing a dedicated circuit in the detachable device. 
     The input/output control unit  410  is configured to include a circuit used to transmit/receive an image to/from the image capturing apparatus  110 , a circuit that analyzes a command received from the image capturing apparatus  110 , a circuit that controls based on a result of analysis, and the like. Commands here are defined by the SD standard, and the input/output control unit  410  can detect some of them. Details of the functions will be described later. The input/output control unit  410  controls to transmit an image to the SD controller  403  in storage processing and transmit an image to the arithmetic processing unit  412  in image analysis processing. If the setting data of switching of processing is received, the input/output control unit  410  transmits the setting data to the processing switching unit  411 . The processing switching unit  411  is configured to include a circuit configured to obtain the information of the image analysis processing function from the storage unit  404  based on the setting data received from the image capturing apparatus  110  and write the information in the arithmetic processing unit  412 . The information of the image analysis processing function includes setting parameters representing, for example, the order and types of operations processed in the arithmetic processing unit  412 , the coefficients of operations, and the like. The arithmetic processing unit  412  is configured to include a plurality of arithmetic circuits needed to execute the image analysis processing function. The arithmetic processing unit  412  executes each arithmetic processing based on the information of the image analysis processing function received from the processing switching unit  411 , transmits the processing result to the image capturing apparatus  110 , and/or records the processing result in the storage unit  404 . As described above, the FPGA  402  extracts the setting data of an execution target processing function included in setting data corresponding to a plurality of processing functions held in advance, and rewrites processing contents to be executed by the arithmetic processing unit  412  based on the extracted setting data. This allows the detachable device  100  to selectively execute at least one of the plurality of processing functions. In addition, by appropriately adding setting data of processing to be newly added, latest processing can be executed on the side of the image capturing apparatus  110 . Note that holding a plurality of setting data corresponding to a plurality of processing functions will be referred to as holding a plurality of processing functions hereinafter. That is, even in a state in which the FPGA  402  of the detachable device  100  is configured to execute one processing function, if the processing contents of the arithmetic processing unit  412  can be changed by setting data for another processing function, this will be expressed as holding a plurality of processing functions. 
     The SD controller  403  is a known control IC (Integrated Circuit) as defined by the SD standard, and executes control of a slave operation of an SD protocol and control of data read/write for the storage unit  404 . The storage unit  404  is formed by, for example, a NAND flash memory, and stores various kinds of information such as storage data written from the image capturing apparatus  110 , the information of the image analysis processing function written in the arithmetic processing unit  412 , and setting data of the FPGA  402 . 
       FIG.  5 A  shows an example of the functional configuration of the detachable device  100 . Also,  FIG.  5 B  shows the detailed configuration of an analysis unit  501 . The detachable device  100  includes, as its functional configuration, for example, the analysis unit  501  and a communication unit  502 . The analysis unit  501  executes analysis processing for an image. 
     The analysis unit  501  executes analysis processing for an image. In this embodiment, the analysis unit  501  executes face detection processing  503 , face characteristic extraction processing  504 , and face characteristic collation processing  505 . However, the present invention is not limited to this. Note that since the face detection processing  503  is the same as the above-described face detection processing  309 , the face characteristic extraction processing  504  is the same as the above-described face characteristic extraction processing  310 , and the face characteristic collation processing  505  is the same as the above-described face characteristic collation processing  311 , a description of these will be omitted. However, processing performance can change in accordance with the hardware performance to execute or the algorithm of analysis processing. The communication unit  502  performs communication with the image capturing apparatus  110  via the I/F unit  401 . 
     Configuration of Server 
       FIG.  6    shows an example of the hardware configuration of the server  130 . The server  130  is formed as a computer such as a general PC, and is configured to include, for example, a processor  601  such as a CPU, memories such as a RAM  602  and a ROM  603 , a storage device such as an HDD  604 , and a communication I/F  605 , as shown in  FIG.  6   . The server  130  can execute various kinds of functions by executing, by the processor  601 , programs stored in the memories and the storage device. 
       FIG.  7 A  shows an example of the functional configuration of the server  130  according to this embodiment. Also,  FIG.  7 B  shows the detailed configuration of an analysis unit  705 . The server  130  includes, as its functional configuration, for example, a network communication unit  701 , a control unit  702 , a display unit  703 , and an operation unit  704 . The network communication unit  701  is connected to, for example, the network  120  and executes communication with an external apparatus such as the image capturing apparatus  110  via the network  120 . Note that this is merely an example and, for example, the network communication unit  701  may be configured to establish direct communication with the image capturing apparatus  110  and communicate with the image capturing apparatus  110  without intervention of the network  120  or other apparatus. The control unit  702  controls such that the network communication unit  701 , the display unit  703 , and the operation unit  704  execute processing of their own. The display unit  703  presents information to the user via, for example, a display. In this embodiment, a result of rendering by a browser is displayed on a display, thereby presenting information to the user. Note that information may be presented by a method such as an audio or a vibration other than screen display. The operation unit  704  accepts an operation from the user. In this embodiment, the operation unit  704  is a mouse or a keyboard, and the user operates these to input a user operation to the browser. However, the operation unit  704  is not limited to this and may be, for example, another arbitrary device capable of detecting a user’s intention, such as a touch panel or a microphone. 
     The analysis unit  705  executes analysis processing for an image. In this embodiment, executable analysis processing includes pre-analysis processing  707 , face detection processing  708 , face characteristic extraction processing  709 , face characteristic collation processing  710 , and post-analysis processing  711 . However, the present invention is not limited to this. Note that the processes executable by the analysis unit  705  are the same as the processes executable by the analysis unit  305 . However, processing performance can change in accordance with the hardware performance to execute or the algorithm of analysis processing. 
     An image registration unit  706  manages face images to be collated by the face characteristic collation processing  710  with a face characteristic analyzed from a captured image. A server load grasping unit  712  grasps the load state of the server  130 . 
     Procedure of Processing 
     An example of the procedure of processing executed in the system will be described next. Note that processing executed by the image capturing apparatus  110  in the following processes is implemented by a processor in the arithmetic processing unit  203  executing a program stored in a memory or the like. In addition, processing executed by the detachable device  100  is implemented by a processor in the arithmetic processing unit  412  executing a program stored in a memory or the like. Furthermore, processing executed by the server  130  is implemented by the processor  601  executing a program stored in the RAM  602 . However, this is merely an example, and processing to be described later may partially or wholly be implemented by dedicated hardware. 
     Overall Procedure 
       FIG.  8    is a view schematically showing a series of procedures of image analysis processing executed by the image analysis system  101 . 
     In step S 801 , the image capturing apparatus  110  detects that the detachable device  100  is mounted by the user. In step S 802 , the image capturing apparatus  110  executes an initialization sequence of the detachable device  100 . 
     In this initialization sequence, predetermined commands are transmitted/received between the image capturing apparatus  110  and the detachable device  100 . The image capturing apparatus  110  is thus set in a state in which it can use the detachable device  100 . 
     In step S 803 , the image analysis system  101  performs face authentication processing for a captured image obtained by the image capturing apparatus  110  and unlocks the electric lock  170 . Here, the face authentication processing is processing implemented using a plurality of sub-processes (the face detection processing function, the face characteristic extraction processing function, and the face characteristic collation processing function). The face authentication processing is executed by one of the image capturing apparatus  110 , the detachable device  100 , and the server  130 . Details of allocation of the face authentication processing will be described later. Also, the processing in step S 803  is repetitively executed for a captured image (each frame image that forms a moving image) obtained by the image capturing apparatus  110 . 
     Procedure of Face Authentication Processing and Electric Lock Unlocking Processing Step S 803   
       FIGS.  9 A- 9 C  are flowcharts showing an example of the procedure of face authentication processing and electric lock unlocking processing (step S 803 ).  FIGS.  9 A- 9 C  show processing of performing face authentication processing by the image capturing apparatus  110 , the detachable device  100 , and the server  130  for an image captured by the image capturing apparatus  110  and unlocking the electric lock  170 . 
     Processes indicated by steps S 901  to S 907 , S 909  to S 914 , S 916  to S 919 , and S 920  to S 922  are processes executed by the image capturing apparatus  110 . Also, processes indicated by steps S 908 , S 915 , and S 920  are processes executed by the detachable device  100 . Furthermore, processes indicated by steps S 931  to S 942  are processes executed by the server  130 . In addition, a process indicated by step S 951  is a process executed by the access controller  150 . 
     In step S 901 , the image capturing control unit  301  captures the peripheral environment. For example, the control unit  304  controls the signal processing unit  302  to process an image captured by the image capturing control unit  301 , thereby obtaining a captured image. 
     In step S 902 , the control unit  304  judges which one of the image capturing apparatus  110 , the detachable device  100 , and the server  130  should execute each process of the face authentication function group. Details of the judgement method will be described later. In this embodiment, the detachable device  100  can execute the face detection processing  503 , the face characteristic extraction processing  504 , and the face characteristic collation processing  505 . Also, the image capturing apparatus  110  can execute the pre-analysis processing  308 , the face detection processing  309 , the face characteristic extraction processing  310 , the face characteristic collation processing  311 , and the post-analysis processing  312 . Furthermore, the server  130  can execute the pre-analysis processing  707 , the face detection processing  708 , the face characteristic extraction processing  709 , the face characteristic collation processing  710 , and the post-analysis processing  711 . 
     In step S 903 , if face detection processing is to be locally executed (by the image capturing apparatus  110  or the detachable device  100 ), the control unit  304   advances to step S 904 . On the other hand, if face detection processing is to be remotely executed (by the server  130 ), the control unit  304  advances to step S 905 . 
     In step S 904 , the control unit  304  controls the analysis unit  305  to execute pre-analysis processing for the captured image input from the control unit  304 , thereby obtaining the image of the pre-analysis processing result. 
     In step S 905 , the control unit  304  controls the network communication unit  307  to transmit the captured image obtained in step S 901  to the server  130 . As an example, the image capturing apparatus  110  transmits a response message to a request message defined by the above-described ONVIF standard to the server  130 , thereby transmitting information to the server  130 . However, the present invention is not limited to this, and information may be transmitted by another message. 
     In step S 906 , if face detection processing is to be executed by the image capturing apparatus  110 , the control unit  304  advances to step S 907 . On the other hand, if face detection processing is to be executed by the detachable device, the control unit  304  advances to step S 908 . 
     In step S 907 , the control unit  304  controls the analysis unit  305  to execute the face detection processing  309  for the image of the pre-analysis processing result, thereby obtaining a face likelihood and face position region information representing the region of the detected face. 
     In step S 908 , the analysis unit  501  executes the face detection processing  503  for the image of the pre-analysis processing result. On the other hand, in step S 909 , the control unit  304  controls the analysis unit  305  to execute the post-analysis processing  312 , thereby creating metadata. 
     In step S 910 , the control unit  304  judges whether a face detection result exists in the metadata. If a face detection result exists, the process advances to step S 908 . If no face detection result exists, the procedure is ended. 
     In step S 911 , if face characteristic extraction processing is to be remotely executed (by the server  130 ), the control unit  304  advances to step S 912 . On the other hand, if face characteristic extraction processing is to be locally executed (by the image capturing apparatus  110  or the detachable device  100 ), the process advances to step S 913 . 
     In step S 912 , the control unit  304  controls the network communication unit  307  to transmit the captured image obtained in step S 901  and the metadata created in step S 909  to the server  130 . 
     In step S 913 , if face characteristic extraction processing is to be executed by the image capturing apparatus  110 , the control unit  304  advances to step S 914 . If face characteristic extraction processing is to be executed by the detachable device, the control unit  304  advances to step S 915 . 
     In step S 914 , the control unit  304  controls the analysis unit  305  to execute the face characteristic extraction processing  310  and extract the face characteristic of the detected face. On the other hand, in step S 915 , the analysis unit  501  executes the face characteristic extraction processing  504  to extract the face characteristic of the detected face. 
     In step S 916 , if face characteristic collation processing is to be remotely executed (by the server  130 ), the control unit  304  advances to step S 917 . On the other hand, if face characteristic collation processing is to be locally executed (by the image capturing apparatus  110  or the detachable device  100 ), the control unit  304  advances to step S 918 . 
     In step S 917 , the control unit  304  controls the network communication unit  307  to transmit the face characteristic extracted in step S 914  or S 915  to the server  130 . 
     In step S 918 , if face characteristic collation processing is to be executed by the image capturing apparatus  110 , the control unit  304  advances to step S 919 . If face characteristic collation processing is to be executed by the detachable device, the control unit  304  advances to step S 920 . 
     In step S 919 , the control unit  304  controls the analysis unit  305  to execute the face characteristic collation processing  311 . On the other hand, in step S 920 , the analysis unit  501  executes the face characteristic collation processing  311 . 
     In step S 921 , if collation is OK as the result of the face characteristic collation processing, the control unit  304  advances to step S 922 . If collation is NG, the procedure is ended. In step S 922 , the control unit  304  controls the network communication unit  307  to transmit an unlocking event to the I/O module  140 . 
     In step S 931 , the control unit  702  of the server  130  controls the network communication unit  701  to receive data from the image capturing apparatus  110 . That is, the captured image (if it is transmitted in step S 905 ), the captured image and the metadata (if these are transmitted in step S 912 ), or the face characteristic (if it is transmitted in step S 917 ) is received. In step S 932 , if the received data is the face characteristic, the control unit  702  advances to step S 939 . Otherwise, the control unit  702  advances to step S 932 . In step S 933 , if the received data are the captured image and the metadata, the control unit  702  advances to step S 935 . Otherwise (that is, if the received data is the captured image), the control unit  702  advances to step S 934 . 
     In step S 934 , the control unit  702  controls the analysis unit  705  to execute the pre-analysis processing  707  for the received captured image, thereby obtaining the image of the pre-analysis processing result. On the other hand, in step S 935 , the control unit  702  control the analysis unit  705  to execute the pre-analysis processing  707  for the received captured image, thereby obtaining the image of the pre-analysis processing result. 
     In step S 936 , the control unit  702  controls the analysis unit  705  to execute the face detection processing  708  for the image of the pre-analysis processing result. In step S 937 , the control unit  702  controls the analysis unit  705  to execute the post-analysis processing  711 , thereby creating metadata. In step S 938 , the control unit  702  judges whether a face detection result exists in the metadata. If a face detection result exists, the process advances to step S 939 . If no face detection result exists, the procedure is ended. 
     In step S 939 , the control unit  702  controls the analysis unit  705  to execute the face characteristic extraction processing  709 . In step S 940 , the control unit  702  controls the analysis unit  705  to execute the face characteristic collation processing  710 , thereby obtaining the collation result. 
     In step S 941 , the control unit  702  judges whether the face likelihood exceeds a predetermined threshold. If the likelihood exceeds the threshold, collation is OK, and the process advances to step S 942 . If the likelihood does not exceed the threshold, collation is NG, and the procedure is ended. In step S 942 , the control unit  702  controls the network communication unit  701  to transmit an unlocking event to the I/O module  140 . 
     In step S 951 , upon receiving the HTTP event (unlocking event) from the image capturing apparatus  110  or the server  130 , the I/O module  140  transmits an electrical control signal to the access controller  150  via the electric wire  180 . Upon receiving the electrical control signal, the access controller  150  unlocks the electric lock  170 . 
     Procedure of Image Processing Execution Place Judgement Processing Step S 902   
       FIGS.  10 A and  10 B  are views showing examples of tables used for image processing execution place judgement processing. Note that in the following explanation, an image processing capability means an index representing whether an apparatus can execute each image processing. On the other hand, a hardware capability means an index of the processing speed (speed) of each image processing. 
     A server table  1001  shows an image processing capability representing whether the server  130  can perform each image processing. The server table  1001  shows that the server  130  has a capability of performing the pre-analysis processing  707 , the face detection processing  708 , the face characteristic extraction processing  709 , the face characteristic collation processing  710 , and the post-analysis processing  711 . 
     An image capturing apparatus table  1002  shows an image processing capability representing whether the image capturing apparatus  110  can perform each image processing. The image capturing apparatus table  1002  shows that the image capturing apparatus  110  has a capability of performing the pre-analysis processing  308 , the face detection processing  309 , the face characteristic extraction processing  310 , the face characteristic collation processing  311 , and the post-analysis processing  312 . 
     A detachable device table  1003  shows an image processing capability representing whether the detachable device  100  can perform each image processing. The detachable device table  1003  shows that the detachable device  100  has a capability of performing the face detection processing  503 , the face characteristic extraction processing  504 , and the face characteristic collation processing  505 . 
     Load state information  1004  shows the load state of the server  130 . Processing of grasping the load state of the server is performed by the server load grasping unit  712 . The load state of the server  130  includes, for example, a low load state  1005 , a medium load state  1006 , and a high load state  1007 . 
     The low load state  1005  is a state in which the number of analysis processes simultaneously executed by the server  130  is 0 or very small (less than a predetermined load), and the analysis processing speed of the server  130  for one analysis process is ideal. The medium load state  1006  is a state in which the server  130  simultaneously executes a plurality of analysis processes (equal to or more than a predetermined load), and the analysis processing speed is lower than in the ideal state. The high load state  1007  is a state in which the server  130  simultaneously executes a plurality of analysis processes (equal to or more than a predetermined load), and an analysis process exists in a queue. If an analysis request is issued in the high load state  1007 , the process is accumulated in the queue, processing waits until processes accumulated in the queue in advance are ended, and the processing is executed after that. 
     The metrics for grasping the server load is not limited to this, and, for example, the server load may be calculated from an average analysis speed in a predetermined period. The server load may be calculated based on the number of connected cameras or a person passage state. 
     Hardware capability information  1008  represents the hardware capability of the image capturing apparatus  110 . The speed of performing each image processing is lower in a low-speed image capturing apparatus  1009  than in a high-speed image capturing apparatus  1010 . To the contrary, the speed of performing each image processing is higher in the high-speed image capturing apparatus  1010  than in the low-speed image capturing apparatus  1009 . 
     Hardware capability information  1011  represents the hardware capability of the detachable device  100 . “Not inserted”  1012  represents a state in which image processing cannot be performed by the detachable device  100  because the detachable device  100  is not inserted into the image capturing apparatus. The speed of performing each image processing is lower in a low-speed detachable device  1013  than in a high-speed detachable device  1014 . To the contrary, the speed of performing each image processing is higher in the high-speed detachable device  1014  than in the low-speed detachable device. 
     A judgment table  1015  is a table in which where to execute each image processing is described in accordance with the load state information  1004 , the hardware capability information  1008 , and the hardware capability information  1011 . That is, the judgment table  1015  is a determination table for uniquely determining which one of the image capturing apparatus  110 , the detachable device  100 , and the server  130  should execute image processing. Note that the judgment table  1015  defines where to execute each image processing depending on at least the load state information  1004 . Also, the judgment table  1015  may be dynamically configured based on the server table  1001 , the image capturing apparatus table  1002 , and the detachable device table  1003 . 
       FIG.  11    is a flowchart showing an example of the procedure of image processing execution place judgement processing (step S 902 ). 
     In step S 1101 , the control unit  304  of the image capturing apparatus  110  controls the network communication unit  701  to obtain the server table  1001  from the server  130 . In step S 1102 , the control unit  304  obtains the image capturing apparatus table  1002 . In step S 1103 , the control unit  304  obtains the detachable device table  1003 . That is, the control unit  304  obtains image processing capability information of each of the server  130  and the image capturing apparatus  110  (capability obtaining). 
     Note that in steps S 1101  to S 1103 , the control unit  304  may confirm that inconsistency does not exist between the obtained tables and the judgment table  1015 . That is, the control unit  304  may confirm that the judgment table  1015  does not include inexecutable analysis processing. If the judgment table  1015  includes inexecutable analysis processing, an error is output, and the processing is ended. Alternatively, the judgment table  1015  is corrected such that no inconsistency occurs. 
     In step S 1104 , the server load obtaining unit  313  controls the network communication unit  701  to issue a server load state obtaining request to the server  130 . The server  130  controls the server load grasping unit  712  to perform server load grasping processing and responds to the image capturing apparatus  110  by the load state information  1004 . Thus, the image capturing apparatus  110  obtains the load state information  1004  from the server  130 . 
     In step S 1105 , the control unit  304  obtains the hardware capability information  1008  of the image capturing apparatus  110 . In step S 1106 , the control unit  304  obtains the hardware capability information  1011  of the detachable device  100 . 
     In step S 1107 , based on the obtained load state information  1004 , hardware capability information  1008 , and hardware capability information  1011 , the image processing control unit  314  judges, in accordance with the judgment table  1015 , the device that should execute each image processing. That is, it is judged which one of the image capturing apparatus  110 , the detachable device  100 , and the server  130  should perform each image processing of face authentication processing. 
     As described above, according to the first embodiment, in the image analysis system  101  including the image capturing apparatus  110 , the detachable device  100 , and the server  130 , the apparatus (place) to execute processing is determined in accordance with at least the load state of the server  130 . Also, the apparatus to execute processing is determined based on the image processing capability of each device or the hardware capability of each device in addition to the load state of the server. This can efficiently utilize the resource of the entire system and optimize the processing speed of the entire system. 
     Second Embodiment 
     In the second embodiment, processing of obtaining the information of the execution time of each process in a server  130 , an image capturing apparatus  110 , and a detachable device  100  and determining where to execute each process of a face authentication function group will be described. The system configuration, the configurations of the apparatuses ( FIG.  1    to 7B), and the overall processing procedure ( FIG.  8   ) are the same as in the first embodiment, and a description thereof will be omitted. Parts different from the first embodiment will be described below. 
     Procedure of Processing 
     Procedure of Image Processing Execution Place Judgement Processing Step S 902   
       FIG.  12    is a view showing an example of the load/processing time of each device. 
     Load state information  1201  is the information of the load state of the server  130 . Processing of grasping the load state information  1201  is performed by a server load grasping unit  712 . The load state of the server  130  is represented by the sum of the execution times and the processing wait times of processes (here, pre-analysis processing  707 , face detection processing  708 , face characteristic extraction processing  709 , face characteristic collation processing  710 , and post-analysis processing  711 ). Note that the server load grasping unit  712  judges the load state of the server  130  based on, for example, the sum of the execution times and the processing wait times of the processes executed in the latest past. 
     Records  1202  to  1204  in the load state information  1201  show typical examples of execution times in the three load states, that is, “low load”, “medium load”, and “high load”. A record  1205  shows an example of the number of waiting processes. 
     The record  1202  shows that, as the execution times, the pre-analysis processing  707  takes 10 ms, the face detection processing  708  takes 50 ms, the face characteristic extraction processing  709  takes 30 ms, the face characteristic collation processing  710  takes 20 ms, and the post-analysis processing  711  takes 5 ms. Note that the processing wait time is assumed to be 0. The record  1203  shows that, as the execution times, the pre-analysis processing  707  takes 20 ms, the face detection processing  708  takes 100 ms, the face characteristic extraction processing  709  takes 60 ms, the face characteristic collation processing  710  takes 40 ms, and the post-analysis processing  711  takes 10 ms. Note that the processing wait time is assumed to be 0. 
     The record  1204  shows that, as the execution times, the pre-analysis processing  707  takes 30 ms, the face detection processing  708  takes 150 ms, the face characteristic extraction processing  709  takes 90 ms, the face characteristic collation processing  710  takes 60 ms, and the post-analysis processing  711  takes 15 ms. In addition, the record  1205  shows the number of waiting processes accumulated in the queue in the high load state. The high load processing wait time is calculated from the record  1204  and the record  1205 . 
     Records  1207  and  1208  in image capturing apparatus information  1206  show typical examples of execution times corresponding to two processing performances, that is, “low speed” and “high speed”. 
     The record  1207  shows that, as the execution times, pre-analysis processing  308  takes 200 ms, face detection processing  309  takes 5,000 ms, face characteristic extraction processing  310  takes 3,000 ms, face characteristic collation processing  311  takes 2,000 ms, and post-analysis processing  312  takes 100 ms. The record  1208  shows that, as the execution times, the pre-analysis processing  308  takes 20 ms, the face detection processing  309  takes 1,000 ms, the face characteristic extraction processing  310  takes 600 ms, the face characteristic collation processing  311  takes 400 ms, and the post-analysis processing  312  takes 10 ms. 
     Records  1210  to  1212  in detachable device information  1209  show typical examples of execution times corresponding to three states, that is, “not inserted”, “low speed”, and “high speed”. Note that as shown in the record  1210 , all the execution times in a case where the detachable device  100  is not inserted are indicated by × (representing that the detachable device is unusable). 
     The record  1211  shows that, as the execution times, face detection processing  503  takes 200 ms, face characteristic extraction processing  504  takes 120 ms, and face characteristic collation processing  505  takes 80 ms. The record  1212  shows that, as the execution times, the face detection processing  503  takes 100 ms, the face characteristic extraction processing  504  takes 60 ms, and the face characteristic collation processing  505  takes 40 ms. 
       FIG.  13    is a flowchart showing an example of the procedure of image processing execution place judgement processing (step S 902 ) according to the second embodiment. The processing from step S 1104  in the first embodiment ( FIG.  11   ) is replaced with processing from step S 1301 . 
     In step S 1301 , the image capturing apparatus  110  obtains load state information from the server  130 . In this processing, a control unit  304  of the image capturing apparatus  110  controls a network communication unit  701  to issue a server load state obtaining request to the server  130 . The server  130  controls a server load grasping unit  712  to perform server load grasping processing and responds to the image capturing apparatus  110  by the load state information  1201 . For example, if the server  130  is in a low load state, the pieces of information shown in the record  1202  are transmitted as the response. 
     In step S 1302 , the control unit  304  obtains the image capturing apparatus information of the image capturing apparatus  110 . For example, the execution time of each process in the analysis unit  305  of the image capturing apparatus  110  is obtained as the image capturing apparatus information. For example, if the processing speed of the image capturing apparatus  110  is the low speed, the pieces of information shown in the record  1207  are transmitted as the response. 
     In step S 1303 , the control unit  304  obtains the detachable device information of the detachable device  100 . For example, the execution time of each process in the detachable device  100  is obtained as the detachable device information. For example, if the processing speed of the detachable device  100  is the low speed, the pieces of information shown in the record  1211  are transmitted as the response. 
     In step S 1304 , based on the obtained load state information of the server  130 , the image capturing apparatus information, and detachable device information, the control unit  304  judges the device that should execute each image processing. That is, the control unit  304  judges which one of the image capturing apparatus  110 , the detachable device  100 , and the server  130  should execute each image processing of face authentication processing. For example, a total execution time is calculated for each of a plurality of combinations of each image processing of the face authentication processing and the apparatus (place) to execute the image processing, and one combination with the shortest execution time (highest processing speed) is determined. 
     As described above, according to the second embodiment, in an image analysis system  101  including the image capturing apparatus  110 , the detachable device  100 , and the server  130 , the execution time of each process in at least the server  130  is obtained. The apparatus (place) to execute processing is determined based on the obtained execution time of each process in the server  130 . Also, the apparatus to execute processing is determined based on the image processing capability of each device or the execution time of each process in the image capturing apparatus  110  or the detachable device  100  in addition to the execution times in the server  130 . This can efficiently utilize the resource of the entire system and optimize the processing speed of the entire system. 
     Third Embodiment 
     In the third embodiment, processing of obtaining accuracy information of each process in a server  130 , an image capturing apparatus  110 , and a detachable device  100  (accuracy obtaining) and determining where to execute each process of a face authentication function group will be described. Redetermination processing performed in accordance with the number of detected faces of face detection results will also be described. The system configuration, the configurations of the apparatuses ( FIG.  1    to 7B), and the overall processing procedure ( FIG.  8   ) are the same as in the first and second embodiments, and a description thereof will be omitted. Parts different from the first and second embodiments will be described below. 
     Procedure of Processing 
     Procedure of Face Authentication Processing and Electric Lock Unlocking Processing Step S 803   
       FIG.  14    is a view showing an example of tables for defining the capability of each device according to the third embodiment. Tables  1401  to  1403  are used in place of the tables  1001  to  1003  shown in  FIG.  10 A  of the first embodiment. Note that in the following description, image processing accuracy means an index representing how accurately each image processing can be executed. 
     The server table  1401  shows the image processing capability and image processing accuracy in the server  130 . The server table  1401  shows that the server  130  has a capability of performing pre-analysis processing  707 , face detection processing  708 , face characteristic extraction processing  709 , face characteristic collation processing  710 , and post-analysis processing  711 . The server table  1401  also shows that the server  130  performs the face detection processing  708  at a high accuracy. 
     The image capturing apparatus table  1402  shows the image processing capability and image processing accuracy in the image capturing apparatus  110 . The image capturing apparatus table  1402  shows that the image capturing apparatus  110  has a capability of performing pre-analysis processing  308 , face detection processing  309 , face characteristic extraction processing  310 , face characteristic collation processing  311 , and post-analysis processing  312 . The image capturing apparatus table  1402  also shows that the image capturing apparatus  110  performs the face detection processing  309  at a low accuracy. 
     The detachable device table  1403  shows the image processing capability and image processing accuracy in the detachable device  100 . The detachable device table  1403  shows that the detachable device  100  has a capability of performing face detection processing  503 , face characteristic extraction processing  504 , and face characteristic collation processing  505 . The detachable device table  1403  also shows that the detachable device  100  performs the face detection processing  503  at a medium accuracy. 
       FIGS.  15 A- 15 C  are flowcharts showing an example of the procedure of face authentication processing and electric lock unlocking processing (step S 803 ) according to the third embodiment. Processes of steps S 1501  to S 1503  are added to the first embodiment ( FIGS.  9 A- 9 C ). 
     In step S 1501 , a control unit  304  of the image capturing apparatus  110   determines whether the likelihood of the face detection result in step S 910  is equal to or less than a threshold. If the likelihood is equal to or less than the threshold, the process advances to step S 905  to re-execute the face detection processing  708  in the server  130  capable of performing more accurate face detection. On the other hand, if the likelihood of the face detection result is more than the threshold, the process advances to step S 1502 . 
     In step S 1502 , the control unit  304  determines whether the number of detected faces of face detection results is plural. If the number of detected faces of face detection results is plural, the process advances to step S 1503 . On the other hand, if the number of detected faces of face detection results is not plural (one), the process advances to step S 911 . 
     In step S 1503 , an image processing control unit  314  determines to perform processing in the image processing execution place determined in step S 902  for the first face detection result in the plurality of face detection results. On the other hand, for other face detection results (second and subsequent face detection results), the image processing execution place is rejudged (redetermined). 
     For example, if it is judged, in step S 902 , to perform face characteristic amount processing in the detachable device  100 , face characteristic amount processing for the first face detection result is performed in the detachable device  100 . For this reason, the number of waiting processes for the face characteristic amount processing in the detachable device  100  is 1. Hence, if a plurality of faces are detected by face detection processing, for the subsequent processing for the second or subsequent face detection result, the image processing execution place is rejudged in consideration of the state of subsequent processing for the first face detection result. 
     As described above, according to the third embodiment, the apparatus (place) to execute processing is determined in consideration of image processing accuracy as well. This can optimize the entire system, including not only the speed but also the accuracy. In addition, if the number of detected faces of face detection results is plural, the image processing execution place is rejudged for the second and subsequent face detection results. This can more efficiently utilize the resource of the entire system. 
     Fourth Embodiment 
     In the fourth embodiment, a form in which image processing execution place judgement processing is performed by a server  130  will be described. The system configuration, the configurations of the apparatuses ( FIG.  1    to 7B), and the overall processing procedure ( FIG.  8   ) are the same as in the first to third embodiments, and a description thereof will be omitted. Parts different from the first to third embodiments will be described below. 
     Procedure of Processing 
     Procedure of Face Authentication Processing and Electric Lock Unlocking Processing Step S 803   
       FIGS.  16 A- 16 C  are flowcharts showing an example of the procedure of face authentication processing and electric lock unlocking processing (step S 803 ) according to the fourth embodiment. As described above, the main difference is to perform image processing execution place judgement processing by the server  130 . More specifically, steps S 1601  to S 1604  are added in place of steps S 902  and S 1503  in the third embodiment. 
     In step S 1601 , a control unit  304  of an image capturing apparatus  110  controls a network communication unit  701  to inquire the server  130  about the image processing execution place. 
     In step S 1602 , the server  130  controls a server load grasping unit  712  to perform server load grasping processing and judges the image processing execution place based on the states of image capturing apparatuses  110   a  to  110   d  and detachable devices  100   a  to  100   d . That is, the image processing execution place is judged based on the information of the plurality of image capturing apparatuses (and detachable devices) existing in the system, unlike the first to third embodiments. The judgement result is then transmitted to the image capturing apparatus  110 . Note that the contents of the image processing execution place judgement processing are the same as in the first to third embodiments, and a description thereof will be omitted. 
     In step S 1603 , the control unit  304  of the image capturing apparatus  110  controls the network communication unit  701  to inquire the server  130  about the image processing execution place again. 
     In step S 1604 , the server  130  controls the server load grasping unit  712  to perform server load grasping processing and rejudges the image processing execution place based on the states of the image capturing apparatuses  110   a  to  110   d  and the detachable devices  100   a  to  100   d . The rejudgement result is then transmitted to the image capturing apparatus  110 . 
     As described above, according to the fourth embodiment, image processing execution place judgement processing is performed by the server  130 . This makes it possible to perform image processing execution place judgement processing based on the information of the plurality of image capturing apparatuses (and detachable devices) existing in the system. That is, it is possible to perform image processing execution place judgement processing corresponding to each of the image capturing apparatuses (and the detachable devices) while considering the balance of the entire system. 
     Other Embodiments 
     In the above-described embodiment, image analysis processing has been described as an example of analysis processing. However, the present invention is also applicable to audio analysis processing. For example, the present invention can be applied to processing of detecting an audio pattern such as a scream, a gunshot, or glass breaking sound. For example, a characteristic amount of an audio is extracted by various audio data analysis methods such as spectrum analysis, and the extracted characteristic amount is compared with the detected audio pattern. By calculating the degree of matching, a specific audio pattern can be detected. 
     When performing audio analysis processing, audio data is divided into audio data of a predetermined time, audio analysis processing is performed using the audio data of the predetermined time as a unit. In addition, the predetermined time appropriately changes depending on the audio pattern of the detection target. For this reason, audio data of a time corresponding to an audio pattern to be detected is input to the detachable device  100 . The detachable device  100  has a function of analyzing the input audio data or a function of holding the input audio data. 
     In the above-described embodiment, the detachable device  100  capable of non-temporarily storing data input from the image capturing apparatus  110  has been described as an example. However, in some embodiments, the detachable device  100  that cannot non-temporarily store data input from the image capturing apparatus  110  may be used. That is, the detachable device  100  may only perform analysis processing for data input from the image capturing apparatus  110 , and need not have the function of non-temporarily storing the data. In other words, the detachable device  100  may be not assumed to be used to store data, like a normal SD card, and may have only the function of analysis processing. 
     Other Embodiments 
     Embodiment(s) of the present invention can also be realized by a computer of a system or apparatus that reads out and executes computer executable instructions (e.g., one or more programs) recorded on a storage medium (which may also be referred to more fully as a ‘non-transitory computer-readable storage medium’) to perform the functions of one or more of the above-described embodiment(s) and/or that includes one or more circuits (e.g., application specific integrated circuit (ASIC)) for performing the functions of one or more of the above-described embodiment(s), and by a method performed by the computer of the system or apparatus by, for example, reading out and executing the computer executable instructions from the storage medium to perform the functions of one or more of the above-described embodiment(s) and/or controlling the one or more circuits to perform the functions of one or more of the above-described embodiment(s). The computer may comprise one or more processors (e.g., central processing unit (CPU), micro processing unit (MPU)) and may include a network of separate computers or separate processors to read out and execute the computer executable instructions. The computer executable instructions may be provided to the computer, for example, from a network or the storage medium. The storage medium may include, for example, one or more of a hard disk, a random-access memory (RAM), a read only memory (ROM), a storage of distributed computing systems, an optical disk (such as a compact disc (CD), digital versatile disc (DVD), or Blu-ray Disc (BD)™), a flash memory device, a memory card, and the like. 
     While the present invention has been described with reference to exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. The scope of the following claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.