Content generation apparatus, control method thereof, storage medium, and computer program product

Abstract

The invention provides a content generation apparatus, a control method thereof, a storage medium, and a computer program product. The problem to be solved is to ensure the authenticity of the generation time of the content. [Solution] The content generation device comprises: a unit for receiving, from a user, an instruction to generate content; a unit for receiving, from a user, an indication to change an authenticity assurance mode for assuring the authenticity of the content to an active state or an inactive state; and a controller for performing control to generate content in a case where an instruction to change the authenticity guarantee mode from the invalid state to the valid state is received and an instruction to generate the content is received, the content includes a generation time of the content based on a reference time that has been adjusted using time information received from the outside.

Description

Technical Field

[0001] The present invention relates to a content generating device and a control method thereof, and a storage medium storing a control program. Background Art

[0002] In recent years, information sharing via the Internet has been actively carried out, and anyone can disclose and transmit various information to unspecified persons. In addition, digital images can be processed in various ways. In such a situation, the information may be transmitted from an unreliable source, and the disclosed information may be illegally tampered with. Therefore, a technology for ensuring the authenticity of the disclosed / transmitted information is needed.

[0003] For example, Japanese Patent Laid-Open No. 2008-5421 discloses such a technology for guaranteeing the authenticity of disclosed / transmitted information. The digital camera disclosed in the publication has a function of adding data for verifying the originality of image data obtained by shooting (specifically, a hash value of image data including the image itself and additional information such as the shooting date and time of the image) to an image file including the image data. This makes it possible to judge whether the image data included in the image file has been changed from the image data at the shooting time by using the hash value given to the image file.

[0004] However, the technology of the above publication allows the user to easily tamper with the shooting date and time of the image data by manually changing the time setting of the digital camera to an arbitrary time. As described above, conventional technology cannot guarantee the authenticity of the generation time of the content generated by the content generation device such as a digital camera. Summary of the invention

[0005] The present invention provides a content generation device capable of ensuring the authenticity of the generation time of the content, a control method thereof and a storage medium storing a control program.

[0006] Therefore, one aspect of the present invention provides a content generating device, comprising: a unit configured to receive an instruction from a user to generate content; a unit configured to receive an instruction from a user to change an authenticity assurance mode for ensuring the authenticity of the content to a valid state or an invalid state; and a controller, which is configured to control to generate the following content when receiving an instruction to change the authenticity assurance mode from the invalid state to the valid state and receiving an instruction to generate the content, the content including a generation time of the content based on a reference time adjusted using time information received from the outside.

[0007] According to the present invention, the authenticity of the generation time of the content is guaranteed.

[0008] 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

[0009] Figure 1A and Figure 1B is a diagram showing the external appearance of a digital camera as a content generating apparatus according to the embodiment.

[0010] Figure 2 It is shown Figure 1A and Figure 1B 2 is a block diagram of a configuration example of a digital camera shown in FIG.

[0011] Figure 3 It is shown Figure 1A and Figure 1B Flowchart of the procedure of shooting control processing executed by the digital camera shown.

[0012] 4A to 4F It is shown Figure 1B A diagram showing an example of a screen displayed on the display unit shown.

[0013] Figure 5 It is shown Figure 3 Flowchart of the process of shooting processing in S318 in .

[0014] Figure 6 It is shown Figure 1A and Figure 1B Figure 2 is a diagram of an example of an image file generated by a digital camera. DETAILED DESCRIPTION

[0015] Hereinafter, embodiments according to the present invention will be described in detail with reference to the accompanying drawings. The following embodiments do not limit the present invention according to the appended claims. Although multiple features are described in the embodiments, not all of these multiple features are essential to the present invention, and these multiple features can be arbitrarily combined.

[0016] Hereinafter, an embodiment in which the content generating apparatus of the present invention is applied to a digital camera capable of capturing still images and recording moving images will be described in detail with reference to the accompanying drawings.

[0017] First, refer to Figure 1A , Figure 1B and Figure 2 The configuration and functions of a digital camera 100 as a content generating apparatus according to this embodiment are described.

[0018] Figure 1A 1 is a front perspective view showing the digital camera 100 with the lens unit 150 detached. Figure 1B is a rear perspective view showing the digital camera 100 .

[0019] like Figure 1B As shown, the back display unit 28 is separated from the viewfinder and displays images and various information. The back display unit 28 is a display device such as an LCD or the like provided on the back of the camera body. The back display unit 28 is provided with a touch panel 70a. The touch panel 70a is a touch operation member capable of detecting contact (touch operation) with the display surface (touch operation surface) of the display unit 28.

[0020] The upper display unit 43 is provided on the upper surface of the digital camera 100, and displays various setting values ​​of the digital camera 100 (such as shutter speed and aperture value, etc.). The shutter button 61 is an operation member for instructing shooting. The mode changeover switch 60 is an operation member for switching the mode between various modes. The terminal cover 40 is a cover for protecting a connector (not shown) to which a connection cable for connecting the digital camera 100 to an external device is connected.

[0021] The main electronic dial 71 is a rotation operation member. The user can change setting values ​​such as shutter speed and aperture value by rotating the main electronic dial 71. The power switch 72 is an operation member for switching the power of the digital camera 100 between ON and OFF. The sub-electronic dial 73 is a rotation operation member. The user can move the selection frame (cursor) and send an image by rotating the sub-electronic dial 73. The four-way key 74 is configured so that its upper part, lower part, left part and right part can be pressed, and a process corresponding to the pressed part of the four-way key 74 can be executed. The setting button 75 is a push button and is mainly used to fix the selection item.

[0022] The motion image button 76 is used to indicate the start or stop of motion image shooting (recording). The AE lock button 77 is a push button. The user can fix the exposure state by pressing the AE lock button 77 in the shooting standby state. The zoom button 78 is an operation button for switching between ON and OFF of the zoom mode in the live view display (LV display) in the shooting mode. The user can enlarge or reduce the live view image (LV image) by operating the main electronic dial 71 after turning on the zoom mode. In the playback mode, the zoom button 78 is used as an operation button for enlarging the playback image or increasing the magnification.

[0023] The playback button 79 is an operation button for switching between the shooting mode and the playback mode. When the playback button 79 is pressed during the shooting mode, the mode is changed to the playback mode, and the playback mode described later can be played. Figure 2 The latest image among the images recorded in the recording medium 200 is displayed on the back display unit 28.

[0024] The menu button 81 is a push button used when the user performs an instruction operation to display a menu screen. When the menu button 81 is pressed, a menu screen in which various settings can be made is displayed on the back display unit 28. The user can intuitively make various settings on the menu screen displayed on the back display unit 28 while using the four-way key 74 and the setting button 75.

[0025] The touch bar 82 (multi-function bar: M-Fn bar) is a linear touch operation member (line touch sensor) capable of accepting touch operation. The touch bar 82 is arranged at a position where the thumb of the right hand can touch the touch bar 82 in a state where the grip portion 90 is gripped by the right hand (in a state where the grip portion 90 is gripped by the little finger, the ring finger, and the middle finger of the right hand) so that the shutter button 61 can be pressed by the index finger of the right hand. That is, the touch bar 82 is arranged at a position where the user can operate in a state (shooting posture) in which the user looks at the viewfinder by bringing the eye into contact with the eyepiece window 16 and can press the shutter button 61 at any time. The touch bar 82 is an acceptance unit capable of accepting a tap operation (an operation of touching and releasing without moving the finger within a predetermined period of time) and a slide operation to the left or right (an operation of touching and moving the touched position without releasing the finger), etc. The touch bar 82 is an operation member different from the touch panel 70a and does not have a display function.

[0026] The communication terminal 10 is used for connecting the digital camera 100 to a communication device described later. Figure 2 The eyepiece window 16 is a part of the eyepiece finder (endoscopic finder) 17. The user can visually recognize the later described Figure 2 The eye proximity detector 57 is an eye contact detection sensor for detecting whether the user (photographer) is in contact with the eyepiece window 16. The cover 202 is for storing the video displayed on the internal electronic viewfinder (EVF) 29 described later. Figure 2 A cover of the groove of the recording medium 200 is provided.

[0027] The grip portion 90 is a holding portion having a shape that is easy for the user to hold with the right hand when holding the digital camera 100. The shutter button 61 and the main electronic dial 71 are arranged at positions where they can be operated by the index finger of the right hand in a state where the digital camera 100 is held by holding the grip portion 90 with the little finger, ring finger, and middle finger of the right hand. In the same state, the sub-electronic dial 73 and the touch bar 82 are arranged at positions where they can be operated by the thumb of the right hand. The thumb rest portion (thumb standby position) 91 is a grip member provided on the back of the digital camera 100 at a position where the thumb of the right hand holding the grip portion 90 can be easily placed in a state where no operating member is operated. The thumb rest portion 91 is formed of a rubber member for enhancing the holding force (gripping feeling).

[0028] Figure 2 It is shown Figure 1A and Figure 1B 1 is a block diagram of a configuration example of a digital camera 100 shown in FIG. Figure 2 , a lens unit 150 on which an interchangeable photographing lens is mounted is detachable from the digital camera 100. Although the lens 103 is generally composed of a plurality of lenses, a single lens is shown here for simplicity. The communication terminal 6 enables the lens unit 150 to communicate with the digital camera 100, and the communication terminal 10 enables the digital camera 100 to communicate with the lens unit 150. The lens unit 150 communicates with the system controller 50 via the communication terminals 6 and 10. The lens unit 150 controls the diaphragm 1 via the diaphragm drive circuit 2 through the internal lens system control circuit 4. The lens unit 150 adjusts the focus by shifting the position of the lens 103 via the AF drive circuit 3 through the lens system control circuit 4.

[0029] The shutter 101 is a focal plane shutter that can freely control the exposure time of the image pickup unit 22 under the control of the system controller 50 .

[0030] The imaging unit 22 has an image sensor such as a CCD or a CMOS for converting an optical image into an electrical signal. The imaging unit 22 may include an imaging plane phase difference sensor for outputting defocus amount information to the system controller 50. The A / D converter 23 converts an analog signal output from the imaging unit 22 into a digital signal.

[0031] The image processor 24 applies predetermined processing (resizing processing such as pixel interpolation and reduction, color conversion processing) to the data from the A / D converter 23 or the data from the memory controller 15. The image processor 24 performs predetermined calculation processing using the captured image data, and the system controller 50 performs exposure control and distance measurement control based on the calculation results obtained by the image processor 24. This enables AF (auto focus) processing, AE (auto exposure) processing, EF (flash pre-emission) processing, etc. of the TTL (through the lens) method. The image processor 24 also performs predetermined calculation processing using the captured image data, and performs AWB (auto white balance) processing of the TTL method based on the obtained calculation results.

[0032] The output data from the A / D converter 23 is written to the memory 32 via the image processor 24 and the memory controller 15. Alternatively, the output data from the A / D converter 23 is written to the memory 32 via the memory controller 15 without passing through the image processor 24. The memory 32 stores image data obtained by the imaging unit 22 and converted into digital data by the A / D converter 23, and image data to be displayed on the back display unit 28 or the EVF 29. The memory 32 has a storage capacity sufficient to store a predetermined number of still images, a predetermined time of moving images, and sound.

[0033] The memory 32 is also used as a memory for image display (video memory). The D / A converter 19 converts the data for displaying an image stored in the memory 32 into an analog signal, and supplies the analog signal to the rear display unit 28 or the EVF 29. The display image data written in the memory 32 is displayed on the rear display unit 28 or the EVF 29 via the D / A converter 19. The rear display unit 28 or the EVF 29 performs display according to the analog signal from the D / A converter 19. The D / A converter 19 converts the digital signal that has been A / D-converted by the A / D converter 23 and stored in the memory 32 into an analog signal, and sequentially transmits the analog signal to the rear display unit 28 or the EVF 29 and displays it, thereby enabling live view (LV) display. Hereinafter, the image displayed in the live view display is referred to as a live view image (LV image).

[0034] The system controller 50 is configured by at least one processor and / or at least one circuit, and controls the entire digital camera 100. The system controller 50 is a processor and also a circuit. The system controller 50 executes a program recorded in the nonvolatile memory 56 to realize each process of this embodiment described later. The system controller 50 also performs display control by controlling the memory 32, the D / A converter 19, the back display unit 28, the EVF 29, and the like.

[0035] The system memory 52 is, for example, a RAM. The system controller 50 develops constants and variables used for the operation of the system controller 50 and a program read from the nonvolatile memory 56 on the system memory 52 .

[0036] The nonvolatile memory 56 is an electrically erasable programmable memory such as an EEPROM, etc. The nonvolatile memory 56 stores constants, programs, etc. for the operation of the system controller 50. The programs mentioned here are processes for executing various flowcharts described later in this embodiment.

[0037] The system timer 53 is a timing unit for measuring time used for various controls and time of a built-in clock.

[0038] The communication unit 54 transmits video signals and audio signals to an external device connected wirelessly or via a wired cable, and receives video signals and audio signals from the external device. The communication unit 54 can also be connected to a wireless local area network (LAN) or the Internet. The communication unit 54 can also communicate with an external device using Bluetooth (registered trademark) (Bluetooth) or Bluetooth low energy.

[0039] The communication unit 54 can transmit images (including LV images) captured by the camera unit 22 and images stored in the storage medium 200, and can also receive various information such as image data and a moving image recording start instruction from an external device. When the communication unit 54 receives a moving image recording start instruction from an external device, the system controller 50 can light up the light emitting unit 102 (see Figure 1A ) or by using the loudspeaker 92 (see Figure 1A ) emits an electronic sound to notify the user of the receipt of the instruction. The external device that communicates with the communication unit 54 may be a smartphone, a tablet terminal, and a PC.

[0040] The orientation detector 55 detects the orientation of the digital camera 100 relative to the gravity direction. Based on the orientation detected by the orientation detector 55, it can be determined whether the image captured by the camera unit 22 is an image captured with the digital camera 100 held horizontally or an image captured with the digital camera 100 held vertically. The system controller 50 can add orientation information corresponding to the orientation detected by the orientation detector 55 to the image file of the image captured by the camera unit 22, and can rotate and record the image. An acceleration sensor or a gyro sensor or the like can be used as the orientation detector 55. It is also possible to detect the motion (pan, tilt, rise, stillness, etc.) of the digital camera 100 using an acceleration sensor or a gyro sensor as the orientation detector 55.

[0041] The eye proximity detector 57 is an eye proximity detection sensor for detecting the approach (eye proximity state) and separation (eye separation state) of the eye (object) relative to the eyepiece window 16 of the eyepiece finder 17. The system controller 50 switches the display state and non-display state of the back display unit 28 and the EVF 29 according to the state detected by the eye proximity detector 57. Specifically, when the display destination is set to automatic switching in the shooting standby state, the display destination is automatically switched between the back display unit 28 and the EVF 29. In the eye separation state, the back display unit 28 is used as the display destination and is set to the display state, and the EVF 29 is set to the non-display state. In the eye proximity state, the EVF 29 is used as the display destination and is set to the display state, and the back display unit 28 is set to the non-display state.

[0042] The eye proximity detector 57 may be an infrared proximity sensor capable of detecting the approach of some object to the eyepiece window 16 of the eyepiece viewfinder 17 including the EVF 29. When the object approaches, infrared light projected from a light emitter (not shown) of the eye proximity detector 57 is reflected by the object and received by a light receiver (not shown) of the infrared proximity sensor. The distance from the eyepiece window 16 to the approaching object may be determined based on the amount of infrared light received.

[0043] In this manner, the eye proximity detector 57 detects eye proximity by detecting the approach distance of the object to the eyepiece window 16. When it is detected that the object approaches within a predetermined distance from the eye separation state with respect to the eyepiece window 16, the eye proximity state with respect to the eyepiece window 16 is detected. When it is detected that the object is separated from the eye proximity state by more than a predetermined distance, the eye separation state is detected.

[0044] The threshold for detecting eye proximity and the threshold for detecting eye separation may be different, for example, by providing a hysteresis. After detecting eye proximity, the eye proximity state is maintained until eye separation is detected. After detecting eye separation, the eye separation state is maintained until eye contact is detected. An infrared proximity sensor is an example, and other sensors may be employed as the eye proximity detector 57 as long as the sensor can detect a state that can be regarded as eye proximity.

[0045] The GPS receiver 119 receives a GPS signal including position information and time information from a GPS satellite (artificial satellite). The digital camera 100 specifies the position of the digital camera 100 and adjusts the reference time of the digital camera 100 based on the GPS signal received by the GPS receiver 119. The digital camera 100 can add information indicating the specified position and a shooting date and time based on the adjusted reference time to a captured image.

[0046] The hash value generator 210 generates (calculates) a hash value by executing a hash function on the image file. Alternatively, the system controller 50 may generate a hash value instead of the hash value generator 210.

[0047] The upper display unit 43 displays various setting values ​​of the camera such as a shutter speed and an aperture value via a drive circuit 44 for the upper display unit.

[0048] The power controller 80 is configured by a battery detection circuit, a DC-DC converter, a switch circuit for switching a block to be powered, and detects whether a battery is attached, the type of battery, and the remaining battery power. The power controller 80 controls the DC-DC converter based on the detection result and the instruction from the system controller 50, and supplies a required voltage to the unit including the storage medium 200 for a required period of time. The power supply 30 is composed of a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery or a NiMH battery or a Li battery, or an AC adapter.

[0049] The storage medium I / F 18 is an interface with the storage medium 200. The storage medium 200 is a memory card, a hard disk, or the like for recording captured images, and is composed of a semiconductor memory, a magnetic disk, or the like.

[0050] The operation unit 70 is an input unit for receiving an operation from a user, and is used to input various operation instructions to the system controller 50. Figure 2 As shown, the operation unit 70 includes a shutter button 61, a mode switching switch 60, a power switch 72, a touch panel 70a, other operation members 70b, etc. The other operation members 70b include a main electronic dial 71, a sub-electronic dial 73, a four-way key 74, a setting button 75, a moving image button 76, an AE lock button 77, an enlargement button 78, a playback button 79, a menu button 81, a touch bar 82, etc.

[0051] The shutter button 61 includes a first shutter switch 62 and a second shutter switch 64. In the middle of a pressing operation of the shutter button 61 (i.e., by so-called half pressing (shooting preparation indication)), the first shutter switch 62 is turned on, and a first shutter switch signal SW1 is generated. In response to the first shutter switch signal SW1, the system controller 50 starts shooting preparation operations such as AF processing, AE processing, AWB processing, and EF processing.

[0052] The second shutter switch 64 is turned on by completing the pressing operation of the shutter button 61, that is, by so-called full pressing (shooting instruction), and generates a second shutter switch signal SW2. In response to the second shutter switch signal SW2, the system controller 50 starts a series of operations of shooting processing from reading a signal from the image pickup unit 22 to writing a shot image as an image file in the storage medium 200.

[0053] The mode switching switch 60 switches the operation mode of the system controller 50 to any one of a still image shooting mode, a moving image shooting mode, a playback mode, etc. The still image shooting mode includes an automatic shooting mode, an automatic scene determination mode, a manual mode, an aperture priority mode (Av mode), a shutter speed priority mode (Tv mode), and a program AE mode (P mode). In addition, there are various scene modes, a custom mode, etc. as shooting settings for various shooting scenes. The user directly switches to any one of these modes by operating the mode switching switch 60. Alternatively, a screen showing a shooting mode list can be displayed in response to the operation of the mode switching switch 60. The user switches to any one of the display modes by using other operating members. Similarly, the moving image shooting mode can include a plurality of modes.

[0054] The touch panel 70a is a touch sensor for detecting various touch operations on the display surface of the back display unit 28 (the operation surface of the touch panel 70a). The touch panel 70a and the back display unit 28 can be configured integrally. For example, the light transmittance of the touch panel 70a is set so as not to interfere with the display of the back display unit 28. The touch panel 70a is attached to the upper layer of the display surface of the display unit 28. Then, the input coordinates on the touch panel 70a and the display coordinates on the display surface of the back display unit 28 are associated with each other. This provides a GUI (Graphical User Interface) that can be operated as if the user can directly operate the screen displayed on the back display unit 28.

[0055] The system controller 50 can detect the following operations or states on the touch panel 70 a .

[0056] (1) A finger or a pen that has not touched the touch panel 70a touches the touch panel 70a anew. That is, the start of touch (hereinafter referred to as "touch-down").

[0057] (2) The finger or the pen keeps touching the touch panel 70a (hereinafter referred to as "touch-on").

[0058] (3) The finger or pen is moving while touching the touch panel 70a (hereinafter referred to as "touch-move").

[0059] (4) The finger or pen that has been touching the touch panel 70a is released from the touch panel 70a. That is, the touch ends (hereinafter referred to as "touch-up").

[0060] (5) Nothing is touching the touch panel 70a (hereinafter referred to as "touch-off").

[0061] When a touch is detected, touch continuation is also detected. After a touch, touch continuation is usually continuously detected unless touch stop is detected. When a touch move is detected, touch continuation is also detected. Even if touch continuation is detected, touch move is not detected unless the touch position is moving. When touch stop is detected for all fingers or pens that were touching, untouch is detected.

[0062] These operations and states and the position coordinates of the touch position of the finger or pen on the touch panel 70a are notified to the system controller 50 via the internal bus. Then, the system controller 50 determines what kind of operation (touch operation) has been performed on the touch panel 70a based on the notified information. For touch movement, the movement amount of the finger or pen on the touch panel 70a can be determined for each of the vertical component and the horizontal component on the touch panel 70a based on the change in the position coordinates.

[0063] When a touch movement of more than a predetermined distance is detected, it is determined that a sliding operation has been performed. The operation of quickly moving a finger on the touch panel 70a for a certain distance while the finger is kept in contact with the touch panel and then releasing the finger from the touch panel is called "flicking". In other words, flicking is an operation of quickly moving a finger across the touch panel 70a as if flicking the touch panel. When a touch movement of more than a predetermined distance at a predetermined speed or more is detected and the touch stops thereafter, it can be determined that a flick has been performed (it can be determined that a flick has been performed following the sliding operation).

[0064] In addition, a touch operation of touching multiple points (e.g., two points) together (multi-touch) and bringing the touch positions close to each other is called pinching, and a touch operation of moving the touch positions away from each other is called pinching. Pinching and pinching are collectively referred to as pinching operations. The touch panel 70a may be any type of touch panel among various types of touch panels such as a resistive film type, a capacitive type, a surface acoustic wave type, an infrared type, an electromagnetic induction type, an image recognition type, and an optical sensor type. There are methods of detecting touch by contacting the touch panel and methods of detecting touch by approaching the touch panel with a finger or a pen, and any method may be used.

[0065] Next, shooting in the case where the authenticity assurance mode is enabled in the digital camera 100 will be described. In this embodiment, when shooting is performed when the authenticity assurance mode is enabled, the image file generated by shooting includes the image file described later. Figure 6On the other hand, when shooting is performed while the authenticity assurance mode is disabled, the image file generated by shooting does not include the historical information 603 described later. Figure 6 In this embodiment, it can be determined whether malicious tampering has been performed based on whether the hash value and signature value included in the historical information 603 have changed.

[0066] Figure 3 It is shown Figure 1A and Figure 1B Flowchart of the procedure of the shooting control process executed by the digital camera 100 shown in FIG. Figure 3 The photographing control process in FIG. 1 shows a series of processes in the case where the digital camera 100 enables the authenticity assurance mode according to an instruction received from the user until photographing is completed. Figure 3 When the shooting control process in starts, the digital camera 100 should disable the authenticity assurance mode and should display the Figure 4A The settings screen is shown. Figure 4A The illustrated setting screen is for the user to issue an instruction to enable or disable the authenticity assurance mode. Figure 3 The shooting control processing in is realized by the system controller 50 loading a program stored in the nonvolatile memory 56 into the system memory 52 and executing the program when the power switch 72 is turned on.

[0067] exist Figure 3 In the process, first, the system controller 50 determines in step S301 whether Figure 4A The system controller 50 waits until the authenticity assurance mode is enabled. Figure 4A The photographing control process proceeds to S302 until an instruction to enable the authenticity assurance mode is given on the setting screen shown, and when an instruction to enable the authenticity assurance mode is given (YES in S301 ), the photographing control process proceeds to S302 .

[0068] In S302, the system controller 50 determines whether the digital camera 100 has a GPS function. For example, when the digital camera 100 does not include the GPS receiver 119 or when the GPS accessory is not connected to the digital camera 100, it is determined that the digital camera 100 does not include the GPS function. In this case, the shooting control process proceeds to S303. The GPS accessory is an accessory component for expanding the GPS function to the digital camera 100, and the process of the GPS accessory receiving the GPS signal from the GPS satellite is controlled by the system controller 50.

[0069] In S303, the system controller 50 determines whether a GPS receiving device is connected to the digital camera 100. The GPS receiving device is a communication device having a GPS function such as a smartphone, a tablet terminal, or a PC, and the process of receiving a GPS signal from a GPS satellite by the communication device is controlled by the controller of the communication device. When it is determined that no GPS receiving device is connected to the digital camera 100, the shooting control process proceeds to S304.

[0070] In S304, the system controller 50 displays on the rear display unit 28 Figure 4B The notification screen includes a message for prompting the user to connect a GPS receiving device or a GPS accessory to the digital camera 100. Thereafter, the shooting control process returns to S301.

[0071] When it is determined in S303 that the GPS receiving device is connected to the digital camera 100, the shooting control process proceeds to S305.

[0072] In S305, the system controller 50 starts receiving time information and position information from the GPS receiving device connected to the digital camera 100. The time information received from the GPS receiving device is time information included in the GPS signal received by the GPS receiving device from the GPS satellite. The position information received from the GPS receiving device is included in the GPS signal received by the GPS receiving device from the GPS satellite, and indicates the position of the GPS receiving device. That is, the position information received from the GPS receiving device is substantially information for indicating the position of the digital camera 100 connected to the GPS receiving device.

[0073] Next, in S306, the system controller 50 determines whether the time information and the position information have been successfully received from the GPS receiving device. When it is determined that the time information and the position information have been successfully received from the GPS receiving device, the shooting control process proceeds to S307.

[0074] In S307, the system controller 50 displays on the rear display unit 28 Figure 4C The success screen shown. The success screen includes a message indicating that the function of obtaining time information and position information from the GPS receiving device is valid. Thereafter, the shooting control process proceeds to S314 described below.

[0075] In S306, when it is determined that the reception of time information and position information from the GPS receiving device has failed, the shooting control process proceeds to S308. An example of failure in receiving time information and position information from the GPS receiving device is when the GPS function is invalid in the GPS receiving device.

[0076] In S308, the system controller 50 displays on the rear display unit 28 Figure 4D The failure screen shown. The failure screen includes a message for indicating a countermeasure for successfully receiving the time information and the position information (for example, a message for prompting the user to check whether the GPS function in the GPS receiving device is valid). Thereafter, the shooting control process returns to S301.

[0077] It is determined in S302 that the digital camera 100 includes the GPS function when the digital camera 100 includes the GPS receiver 119 or when the GPS accessory is connected to the digital camera 100 which does not include the GPS receiver 119. In this case, the shooting control process proceeds to S309.

[0078] In S309, the system controller 50 determines whether a GPS signal is being received. When determining that a GPS signal is not being received, the system controller 50 enables the GPS function in the digital camera 100. Thereafter, the shooting control process proceeds to S310.

[0079] In S310, the system controller 50 controls the GPS receiver 119 or the GPS accessory to start receiving GPS signals from GPS satellites. Next, in S311, the system controller 50 determines whether the reception of the GPS signal is successful. When it is determined that the reception of the GPS signal fails, the shooting control process proceeds to S312. For example, the reception of the GPS signal fails when the user carrying the digital camera 100 is indoors or underground and cannot correctly receive the signal from the GPS satellite.

[0080] In S312, the system controller 50 displays on the rear display unit 28 Figure 4E The reception failure notification screen shown. The reception failure notification screen includes a message indicating that the reception of the GPS signal has failed and a message indicating a countermeasure for making the reception of the GPS signal successful. Thereafter, the shooting control process returns to S301. As described above, in this embodiment, when the digital camera 100 cannot receive a GPS signal from a GPS satellite or cannot receive time information and position information from a GPS receiving device ("No" in S306), the authenticity assurance mode is maintained in an invalid state. This can prevent the generation of an image file including a shooting date and time based on an inaccurate reference time set without using time information obtained from the outside.

[0081] On the other hand, if it is determined in S311 that the reception of the GPS signal is successful, the shooting control process proceeds to S313. In S313, the system controller 50 displays the image on the back display unit 28. Figure 4F The reception success notification screen shown. The notification screen includes, for example, a message indicating that the reception of the GPS signal is enabled by enabling the authenticity assurance mode.

[0082] Next, in S314, the system controller 50 changes the interval between the timings at which position information is obtained from the outside (hereinafter referred to as the "position information obtaining interval") to be shorter than the preset interval. The position information obtaining interval is the interval between the timings at which the GPS receiver 119 or the GPS accessory receives a GPS signal including the position information of the digital camera 100 from a GPS satellite. Alternatively, the position information obtaining interval is the interval between the timings at which the digital camera 100 receives position information from a GPS receiving device. As described above, the position information received from the GPS receiving device is position information related to the GPS receiving device included in the GPS signal received by the GPS receiving device from a GPS satellite, and is substantially position information related to the digital camera 100 connected to the GPS receiving device. In S314, for example, the position information obtaining interval is changed to one second, which is the shortest interval that can be set in the digital camera 100. This enables more accurate position information related to the digital camera 100 to be obtained.

[0083] Next, in S315, the system controller 50 changes the time setting mode to the automatic update mode. When the time setting mode is changed to the automatic update mode, the reference time in the digital camera 100 is adjusted using time information obtained from the outside. The time information obtained from the outside is, for example, time information included in a GPS signal received by the GPS receiver 119 or a GPS accessory. The time information obtained from the outside is time information obtained from a GPS receiving device connected to the digital camera 100, and is time information included in a GPS signal received by the GPS receiving device from a GPS satellite.

[0084] Next, in S316, the system controller 50 prohibits manual change of the reference time. This can prevent a situation where a malicious user changes the reference time of the digital camera 100 to a time different from the actual time and assigns a date and time different from the actual date and time to an image file obtained by shooting as a shooting date and time. Thereafter, the shooting control process proceeds to S317. In addition, when it is determined in S309 that the GPS signal is being received, the shooting control process also proceeds to S317.

[0085] In S317, the system controller 50 changes the setting value of the authenticity assurance mode to "ON", where "ON" is used to indicate that the authenticity assurance mode is effective. The changed setting value is stored in the memory 32. Although the configuration in which the setting value of the authenticity assurance mode is not changed to "ON" when the GPS receiver 119 cannot receive the GPS signal or when the time information and position information received from the GPS receiving device fail is described in the present embodiment, this configuration is not restrictive. For example, in the above case, when the user changes the reference time in the digital camera 100 after changing the setting value of the authenticity assurance mode to "ON", the user's change to the reference time can be recorded in the following description. Figure 6 This makes it possible to notify other users who browse image files generated by the digital camera 100 in a state where the reference time in the digital camera 100 has been changed by the photographer that there is a concern that the image file has been generated at a time different from the actual time.

[0086] Next, in S318, the system controller 50 executes the Figure 5 Next, in S319, the system controller 50 determines whether an instruction to disable the authenticity assurance mode is given. The system controller 50 waits until an instruction to disable the authenticity assurance mode is given, and when an instruction to disable the authenticity assurance mode is given ("Yes" in S319), the shooting control process proceeds to S320.

[0087] In S320 , the system controller 50 changes the setting value of the authenticity assurance mode to “OFF”, where “OFF” is used to indicate that the authenticity assurance mode is invalid. The changed setting value is stored in the memory 32 .

[0088] Next, in S321, the system controller 50 determines whether a GPS signal is received before the setting value of the authenticity assurance mode is changed to "ON" in S317. When it is determined that a GPS signal is received before the authenticity assurance mode is changed to "ON" in S317, the shooting control process is terminated. When it is determined that a GPS signal is not received before the authenticity assurance mode is changed to "ON" in S317, the shooting control process proceeds to S322.

[0089] In S322, the system controller 50 disables the GPS function and ends the reception of the GPS signal. In S322, the settings that have been automatically changed accompanying the successful reception of the GPS signal can be returned to the original settings, for example, by allowing manual change of the reference time. Thereafter, the shooting control process is terminated.

[0090] Figure 5 It is shown Figure 3Flowchart of the shooting processing process of S318 in . Figure 5 The shooting process in is started when a shooting start operation (such as full pressing of the shutter button 61) is received, and ends when a shooting end operation (such as stop pressing of the shutter button 61) is received.

[0091] exist Figure 5 In S501 of the present invention, first, the system controller 50 drives the shutter 101 disposed on the subject side of the image pickup unit 22 so as to control the exposure time. Next, in S502, the system controller 50 performs an image pickup process in which the image pickup unit 22 converts light from the subject received via the shutter 101 into an electrical signal (analog image data). Next, in S503, the system controller 50 applies image processing such as development processing and encoding processing to the electrical signal obtained by the image pickup process of S502, and generates an image data. Figure 6 The image data 604 in.

[0092] Next, in S504, the system controller 50 generates Figure 6 The metadata 601 is a metadata generated by the digital camera 100. Figure 6 The image file 600 in FIG. 6 is data of the image file 600 , and includes shooting information 602 and history information 603 .

[0093] The shooting information 602 is information when the image capturing process for generating the image data 604 is performed, and includes, for example, the shooting date and time, the photographer, the image size, the manufacturer or model of the digital camera 100, various shooting parameters set at the time of shooting, the shooting location, a thumbnail image, etc. The shooting information 602 is generated according to a predetermined technical standard such as the EXIF ​​(Exchangeable Image File) format.

[0094] The shooting date and time included in the shooting information 602 is determined based on a reference time that has been adjusted using time information obtained from the outside. The shooting location included in the shooting information 602 is position information included in a GPS signal received by the digital camera 100 from a GPS satellite, or position information obtained from a GPS receiving device connected to the digital camera 100. The GPS receiving device receives a GPS signal including position information from a GPS satellite. In addition, when the shooting date and time are manually input, information indicating that the shooting date and time are manually input may be recorded in the shooting information 602.

[0095] The history information 603 is information for proving the credibility of the image data 604 and is used when verifying the source and history of the image data 604. The history information 603 is generated according to a predetermined technical standard such as C2PA (Content Source and Authenticity Alliance) and has a prescribed structure. The history information 603 includes a history (assertion) 613 and a hash value 623 and a digital signature 633 for verifying the history 613.

[0096] The history 613 includes history identification information (manifest ID) for uniquely identifying the history, edit history information for indicating the edit content of the image data 604, edit tool information for indicating the tool used for editing, information about the creator of the image data 604, etc. Since the image data 604 generated in S503 is generated only by shooting and is not edited, information indicating "generated" is recorded in the edit history, and information indicating the editing tool of the digital camera 100 is recorded. In addition, when thumbnail data and metadata at the time of shooting and editing are included in the history 613, they can be used to compare and verify the changed parts.

[0097] Return to reference Figure 5 , the system controller 50 generates a hash value 623 in S505. Specifically, the system controller 50 performs a hash function on the binary data of the image data 604 and the history 613, and generates a hash value 624 of the image data and a hash value 626 of the history. The system controller 50 also performs a hash function on the binary data of the shooting information 602 to generate a hash value 625 of the shooting information. In addition, a hash value may be generated for finer units such as an edit history, a creator, thumbnail data, and metadata, so as to detect tampering of the history 613 in finer units.

[0098] Then, in S506, the system controller 50 generates a digital signature 633. The digital signature 633 includes information indicating a signature value, a signer, and a signature date and time. The signature value is generated by encrypting the hash value 623 generated in S505 using a pre-prepared key. The public key paired with the key used here is also included in the digital signature 633. In order to prove that the public key is reliable, information indicating that the manufacturer of the digital camera 100 is the signer, or a public key certificate indicating that the public key has been authenticated by a certificate authentication authority can be included in the digital signature 633. By attaching the digital signature 633 including such a signer to the image file 600, it can be indicated that the image file is reliable. Instead of the manufacturer, the model name of the digital camera 100 can be used as the signer. The signature date and time is the date and time when the generation of the digital signature 633 is completed. The shooting date and time can also be included in the history 613.

[0099] Next, in S507, the system controller 50 generates an image file 600 by adding metadata 601 including shooting information 602 and history information 603 to the image data 604. Here, when the image data 604 is a still image, the image file 600 is generated according to the JPEG format, and when the image data is a moving image, the image file 600 is generated according to the MPEG format. Thereafter, the shooting process ends.

[0100] As described above, in this embodiment, when the digital camera 100 performs shooting in the authenticity assurance mode, the image file 600 is generated. The image file 600 may be edited. When the image file 600 is edited by a legal process using an authorized editing tool, the history information 603 is newly generated according to a predetermined technical standard based on the edited content, and the history information 603 is added to the metadata 601 of the image file 600. Whenever the image file 600 is edited, the history information 603 is newly generated, and the history information 603 is added to the metadata 601 of the image file 600. On the other hand, when the image file 600 is edited by using an unauthorized editing tool or by an unauthorized process, the history information 603 may not be added to the image file 600, or the history information 603 added to the image file 600 may not match the predetermined technical standard.

[0101] Furthermore, generation of a hash value or a signature value enables detection of tampering of the image file 600. For example, a hash function is performed on binary data of the image data 604 of the image file 600 to generate a hash value. Then, the generated hash value is compared with the hash value 624 of the image data of the image file to be judged. This enables verification of whether the image data has been tampered with.

[0102] Similarly, a hash function is performed on the binary data of the shooting information 602 of the image file 600 to generate a hash value. The generated hash value is compared with the hash value 625 of the shooting information of the image file to be judged. This makes it possible to verify whether the shooting information including the shooting date and time, the shooting location, etc. has been tampered with.

[0103] Furthermore, a hash function is performed on the binary data of the history 613 to generate a hash value. Then, the generated hash value is compared with the hash value 626 of the history of the image file to be judged. This makes it possible to verify whether the history information 603 has been tampered with.

[0104] At this time, the binary data to be compared can be compared for each finer unit such as editing history, creator, thumbnail data, and metadata. The signature value can be decrypted by the public key, and it can be determined that the verification of the signature value is successful when the hash values ​​are consistent. In this way, a mechanism for detecting tampering can be incorporated into the image file.

[0105] According to the above-described embodiment, when an instruction to change the authenticity assurance mode from the invalid state to the valid state is received and an instruction to generate an image file is received, an image file 600 including a photographing date and time based on a reference time adjusted using time information received from the outside is generated. Thus, the image file 600 can include a photographing date and time based on a reference time that has not been tampered with, and the authenticity of the generation time of the image file 600 can be guaranteed.

[0106] In the above embodiment, the image file 600 includes the hash value 623 generated in S505 and the digital signature 633 generated in S506 in addition to the shooting date and time. This ensures the authenticity of the image data included in the image file 600 except for the generation time of the image file 600.

[0107] In the above-described embodiment, the time information received from the outside is the time information included in the GPS signal received from the GPS satellite by the GPS receiver 119. Thus, the reference time can be adjusted with high accuracy.

[0108] In the above-described embodiment, the time information received from the outside is time information included in a GPS signal received from a GPS satellite by a GPS accessory connected to the digital camera 100 in a configuration in which the digital camera 100 does not include the GPS receiver 119. This enables time adjustment of the reference time with high accuracy in a configuration in which the digital camera 100 does not include the GPS receiver 119.

[0109] In the above embodiment, when an instruction to change the authenticity assurance mode from the valid state to the invalid state is received, the GPS receiver 119 is stopped from receiving GPS signals from the GPS satellite. Thus, when the authenticity assurance mode is valid, the authenticity of the generation time of the image file 600 is guaranteed, and when the authenticity assurance mode is invalid, unnecessary power consumption can be reduced.

[0110] When the setting value of the authenticity assurance mode is "OFF" and the photographing process is performed after the process in S322, the system controller 50 performs the same operation as that from Figure 5 The same processing as that of S501 to S503 in , and then the shooting information 602 is added to the image data 604 as the metadata 601 to generate the image file 600. That is, the processing in S505 and S506 is not performed, and the history information 603 and the information related to the guarantee of the authenticity of the image data such as the hash value and the digital signature are not added. Therefore, in the above-mentioned embodiment, when the authenticity of the shooting date and time cannot be guaranteed, the authenticity of the image data may not be guaranteed.

[0111] In the above-described embodiment, the time information received from the outside is the time information received from the GPS receiving device connected to the digital camera 100, and the time information is included in the GPS signal received by the GPS receiving device from the GPS satellite. Thus, even if the digital camera 100 does not have a GPS function, the shooting date and time based on the reference time that has not been tampered with can be included in the image file 600.

[0112] In the above embodiment, when receiving an instruction to activate the invalidated authenticity assurance mode, the user is prohibited from changing the reference time. This can prevent a malicious user from tampering with the reference time.

[0113] In the above-described embodiment, when an instruction to change the authenticity assurance mode from the invalid state to the valid state is accepted and the reception of time information from the outside fails, a countermeasure for successfully receiving time information from the outside is notified to the user. This enables the user who takes pictures with the digital camera 100 to easily cope with the process of successfully receiving time information from the outside that is necessary for ensuring the authenticity of the generation time of the image file 600.

[0114] In the above embodiment, the digital camera 100 is an image pickup device for capturing an image of a subject to generate image data and generating an image file including the image data as content. This can ensure the authenticity of the generation time of the image file 600 in such an image pickup device.

[0115] In this embodiment, when operating in the authenticity assurance mode, the digital camera 100 enables the GPS function and receives GPS signals to set and update the accurate time. However, other methods may be used. For example, when the digital camera 100 operates in the authenticity assurance mode, the Wi-Fi communication function may be enabled. In this case, the digital camera 100 may be connected to a Wi-Fi router to receive time information, and the digital camera 100 may adjust the reference time based on the received time information. This may ensure the authenticity of the generation time of the content in a device that does not have a GPS function but has a Wi-Fi communication function. The Wi-Fi router periodically accesses a network time protocol (NTP) server to adjust the time, and thereby maintains the accurate time.

[0116] In a configuration in which the digital camera 100 operates in the authenticity assurance mode and obtains time information from an external device (such as a smartphone or PC) connected to the digital camera 100, the time information may be time information received by the external device from a Wi-Fi router. This can ensure the authenticity of the generation time of content in a configuration in which communication is performed with an external device that does not have a GPS function but has a Wi-Fi communication function.

[0117] When the digital camera 100 is operated in the authenticity assurance mode, the time adjustment function of the radio clock can be enabled. In this case, the reference time can be adjusted based on the date and time information (time code) included in the radio wave received from the standard radio wave transmission station. This can ensure the authenticity of the generation time of the content even if the GPS function is not provided.

[0118] When the digital camera 100 operates in the authenticity assurance mode, the "automatic setting of date and time" can be enabled to automatically obtain time information from the GPS signal, Wi-Fi router, or standard time signal transmission station (NITZ) as described above, so as to adjust the reference time. This enables the digital camera 100 to ensure the authenticity of the generation time of the content.

[0119] Furthermore, when the digital camera 100 changes the "automatic setting of date and time" from the enabled state to the disabled state in response to the user's operation, the authenticity assurance mode may also be automatically changed from the enabled state to the disabled state. In this case, before the "automatic setting of date and time" is changed from the enabled state to the disabled state, a message indicating that the authenticity assurance mode is also changed from the enabled state to the disabled state may be displayed on the screen to notify the user.

[0120] Although the configuration in which an image file is generated as an example of content is described in the present embodiment, the content is not limited to the image file. For example, the present invention is also applicable to a configuration in which an audio file including audio data is generated.

[0121] Although a digital camera is described as an example of the content generation device of the present invention in this embodiment, the content generation device is not limited to a digital camera. The content generation device may be a smartphone, a tablet terminal, a PC, etc. that can generate content and allow a user to change a reference time in the content generation device for determining the generation time of the content.

[0122] Other embodiments

[0123] The embodiments of the present invention may also be implemented by providing software (program) for performing the functions of the above-described embodiments to a system or device via a network or various storage media, and a computer or a central processing unit (CPU) or a microprocessing unit (MPU) of the system or device reads and executes the program.

[0124] 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.

[0125] This application claims the benefit of Japanese Patent Application No. 2023-095412 filed on Jun. 9, 2023 and Japanese Patent Application No. 2024-040109 filed on Mar. 14, 2024, which are hereby incorporated by reference herein in their entirety.

Claims

1. A content generating device, comprising: A unit configured to receive an instruction from a user to generate content; a unit configured to receive an instruction from a user to change an authenticity assurance mode for ensuring the authenticity of the content to a valid state or an invalid state; as well as A controller configured to control, upon receiving an instruction to change the authenticity assurance mode from the invalid state to the valid state and receiving an instruction to generate the content, to generate the content, the content including a generation time of the content based on a reference time adjusted using time information received from the outside.

2. The content generating device according to claim 1, wherein: Upon receiving an instruction to change the authenticity assurance mode from the invalid state to the valid state and receiving an instruction to generate the content, the controller generates content including the generation time, a hash value generated by performing a hash function on the content, and a digital signature generated by encrypting the hash value using a key.

3. The content generating device according to claim 1 or 2, further comprising a receiving unit configured to receive a signal from an artificial satellite; in, The time information received from the outside is time information included in the signal received by the receiving unit from the artificial satellite.

4. The content generating device according to claim 3, wherein: When an instruction to change the authenticity assurance mode from the valid state to the invalid state is received, the reception unit stops receiving a signal from the artificial satellite.

5. The content generating device according to claim 1 or 2, wherein: The time information received from the outside is time information included in a signal received from an artificial satellite by the accessory component connected to the content generating device to expand the GPS function.

6. The content generating device according to claim 1 or 2, wherein: The time information received from the outside is time information received from an external device connected to the content generating device, The time information received from the external device is the time information included in the signal received by the external device from the artificial satellite, and The controller included in the external device controls a process for receiving a signal from the artificial satellite.

7. The content generating device according to claim 1 or 2, wherein: The user can change the reference time.

8. The content generating device according to claim 7, wherein: The content generating device is controlled to prohibit a user from changing the reference time, if receiving an instruction to change the authenticity assurance mode from the invalid state to the valid state.

9. The content generating device according to claim 1 or 2, wherein: The controller generates content including location information obtained from the outside, and Here, when an instruction to change the authenticity assurance mode from the invalid state to the valid state is received, an interval between timings of obtaining the position information from the outside is changed to be shorter than a preset interval.

10. The content generating device according to claim 1 or 2, wherein: When an instruction to change the authenticity assurance mode from the invalid state to the valid state is received and the time information cannot be received from the outside, the authenticity assurance mode is maintained in the invalid state.

11. The content generating device according to claim 1 or 2, wherein: When receiving an instruction to change the authenticity assurance mode from the invalid state to the valid state, the time information cannot be received from the outside, and the user changes the reference time, the controller generates content including information indicating that the reference time has been changed by the user.

12. The content generating device according to claim 1 or 2, wherein: In a case where an instruction to change the authenticity assurance mode from the invalid state to the valid state is received and the time information cannot be received from the outside, a countermeasure for successfully receiving the time information from the outside is notified.

13. The content generating device according to claim 1 or 2, comprising an imaging device for generating image data by capturing an image of a subject, and generating an image file including the image data as the content.

14. A control method for a content generating device, the control method comprising the following steps: receiving instructions from a user to generate content; receiving an instruction from a user to change an authenticity assurance mode for ensuring the authenticity of the content to a valid state or an invalid state; as well as When an instruction to change the authenticity assurance mode from the invalid state to the valid state is received and an instruction to generate the content is received, content including a generation time of the content based on a reference time adjusted using time information received from the outside is generated.

15. A non-transitory computer-readable storage medium storing a control program, wherein the control program causes a computer to execute a control method for a content generating device, the control method comprising the following steps: receiving instructions from a user to generate content; receiving an instruction from a user to change an authenticity assurance mode for ensuring the authenticity of the content to a valid state or an invalid state; as well as When an instruction to change the authenticity assurance mode from the invalid state to the valid state is received and an instruction to generate the content is received, content including a generation time of the content based on a reference time adjusted using time information received from the outside is generated. 16 . A computer program product comprising a control program, wherein the control program causes a computer to execute the control method according to claim 14 .

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