JP2011100250A - Digital camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To maintain confidentiality when a camera is lost or stolen, and prevent an image from being viewed by the other users, or to prevent image data from being transferred to the other users even when one camera is shared by a plurality of users. <P>SOLUTION: When external equipment is connected to a camera so as to be communicable, an encryption key corresponding to the external equipment is created. When an image is captured in a communicable state, image data are encrypted with the encryption key and recorded. The encrypted image data can be prevented from being decrypted with an encryption key corresponding to any other external equipment, and from being displayed. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a digital camera having a security function, and more particularly, to an image captured by a camera so that others cannot see it.

  There is known a digital camera that performs user authentication and encrypts image data using an encryption key to protect the confidentiality of the image data (see, for example, Patent Document 1).

JP 2006-13782 A

  The security function not only keeps the security when the camera is lost or stolen, but also keeps confidentiality for other users in the usage mode where one camera is used by multiple users. It must be.

The digital camera according to the present invention generates and records image data by imaging, and can display the recorded image data as an image on a display device, and communication means for communicating with an external device. When imaging is performed in a state in which communication with an arbitrary external device is possible, control means for permitting display of the image data generated and recorded by the imaging on the display device only in a state in which communication with the external device is possible It is characterized by comprising.
A digital camera according to another invention generates and records image data by imaging, and can transfer the recorded image data to the outside. When image capturing is performed in a state where communication with the external device is possible, the image data generated and recorded by the imaging includes control means for permitting transfer to the outside only in a state where communication with the external device is possible. It is characterized by doing.

  According to the present invention, when a camera is lost or stolen, the image can be seen by other users even in a usage mode in which a single camera is reused by a plurality of users as well as confidentiality. Or the image data can be prevented from passing to other users.

The control block diagram of the digital camera in one Embodiment of this invention. The main flowchart explaining operation | movement of a camera. The flowchart which shows the detail of an encryption key creation process. The flowchart which shows the detail of an imaging process. The flowchart which shows the detail of reproduction | regeneration processing. The flowchart which shows the detail of a transfer process.

An embodiment of the present invention will be described with reference to FIGS.
FIG. 1 is a control block diagram of the digital camera in the present embodiment. The subject luminous flux that has passed through the photographic lens 1 is imaged by the imaging device 2, and the imaging signal is input to the image processing unit 3. The image processing circuit 3a constituting the image processing unit 3 performs various processes on the input imaging signal to generate image data. The generated image data is recorded in a recording medium 5 such as a memory card by a recording / reproducing circuit 3c in a file format that can be handled by a computer.

  In the reproduction mode, the image data recorded on the recording medium 5 can be read out by the recording / reproducing circuit 3c and displayed as an image on the liquid crystal monitor 4 through processing by the image processing circuit 3a and the display circuit 3b.

  The control unit 6 includes a CPU, a memory, and the like, and controls the image processing unit 3 and a circuit (not shown) in response to an input from the operation unit 7. The operation unit 7 includes a power button, a release button, various operation members used for reproduction operation, information input, and the like. Memory includes volatile and non-volatile memory.

  In addition, the camera of this embodiment can communicate with the external device 20 via the communication unit 8. Using this communication function, it is possible to transfer the image data recorded on the recording medium 5 to the external device 20 and to realize a security function described later. The type of the external device 20 is not limited, and may be, for example, a personal computer, or a portable device such as a mobile phone if it is mainly used for a security function. The communication method may be wired / wireless, and may be a wireless communication connection via a public line, for example. The configuration of the communication unit 8 varies depending on the communication method. Further, a communication unit for transferring image data (for example, wired connection to a personal computer) and a communication unit for security function (for example, wireless connection to a mobile phone) may be provided separately.

Next, a security function in the camera will be described with reference to the flowcharts of FIGS.
The security function here refers to a function for preventing an image recorded on the recording medium 5 from being seen by others.

  When the power of the camera is turned on, the program of FIG. When the external device registration operation by the user is confirmed in step S1, the external device 20 is registered in step S2. That is, since the security function uses communication with the external device 20, it is necessary to register the external device 20 in the camera. The external device registration is a process of acquiring device-specific information (for example, a MAC address) from the external device 20 in a communicable state, and storing the information as identification information in a camera memory (non-volatile memory). is there. Multiple types of external devices 20 can be registered. For example, registration may be performed by selecting “External device registration” from the menu screen.

  In step S3, it is determined whether or not a confidential mode setting operation or canceling operation has been performed. The confidential mode is a mode in which the security function is used. When the setting operation is performed, the process proceeds from step S4 to step S5 to set the confidential mode, and then proceeds to the encryption key generation process in step S6. On the other hand, if a release operation has been performed, the confidential mode is canceled in step S7, and the process proceeds to step S8.

  FIG. 3 shows details of the encryption key creation process. The encryption key is a software key for encrypting the image data. The encrypted image data cannot be decrypted unless it is the encryption key, and if it cannot be decrypted, it can be reproduced (displayed). Can not.

  In step S61, it is determined whether or not at least one external device 20 is registered. If no device is registered, the security communication flag is turned off in step S68, a warning that the security function cannot be used is issued in step S69, and the process returns. If at least one external device 20 is registered, communication with the external device 20 is attempted in step S62, and it is determined whether communication with the registered device is possible in step S63. This is performed by comparing the device-specific information acquired from the external device 20 with the registered (recorded) information. If the external device is not communicably connected, or if it is communicably connected but not a registered device, step S63 is denied and the process proceeds to step S68. When step S63 is affirmed, the process proceeds to step S64, and the security communication flag is turned on.

  In step S65, it is determined whether or not an encryption key has already been generated and stored. If not, an encryption key is created in step S67, the key is stored in a volatile memory, and the process returns. Here, since the encryption key is created based on the unique information of the communicable external device 20, the encryption key created at that time is different. Also, since the encryption key is stored in the non-volatile memory, it is erased when the camera is turned off. However, the same encryption key to be created next time is created for the same external device 20 as the previous one. . That is, each external device 20 and the encryption key correspond one-to-one.

  If the encryption key has already been stored, the process proceeds to step S66, and it is determined whether or not the communication destination external device 20 is different from the previous one. If the communication-destination external device 20 is changed while the camera is powered on, step S66 is affirmed, and the process proceeds to step S67 to create an encryption key corresponding to the new external device 20. If step S66 is negative, the process returns.

  In step S8 in FIG. 2, it is determined whether or not the mode is the confidential mode. In the case of the confidential mode, the security communication flag is determined in step S9. If it is on, the process proceeds to step S10, and if it is off, the process returns to step S1. That is, when the security communication flag is off, subsequent release operations, playback operations, transfer operations, and the like are not accepted. In order to accept these, it is only necessary to enable communication with the registered external device 20 or cancel the confidential mode. Note that the confidential mode may be automatically canceled when communication with the registered device is impossible.

  If the release operation is confirmed in step S10, the process proceeds to the imaging process in step S11. If the reproduction operation is confirmed in step S12, the process proceeds to the reproduction process in step S13. If the transfer operation is confirmed in step S14, the process proceeds to step S15. Proceed to the transfer process.

  FIG. 4 shows the details of the imaging process (step S11). In step S111, imaging is performed, and image data is generated based on the obtained image data. In step S112, it is determined whether or not the confidential mode is set. If the confidential mode is not set, the process proceeds to step S114, and the generated image data is recorded on the recording medium 5. If it is the confidential mode, the process proceeds to step S113, and the generated image data is encrypted with the stored encryption key, and the process proceeds to step S114 to record the encrypted image data. Then return.

  Here, the entire image data may be encrypted, but a method of encrypting only the header portion without encrypting the image main body portion of the image data may be used. Thereby, the time required for encryption can be shortened. If the header part cannot be decrypted, the image cannot be reproduced even if the image body part is not encrypted.

  FIG. 5 shows details of the reproduction process (step S13). In step S131, it is determined whether or not image data has been recorded on the recording medium 5 in response to the reproduction operation. If the determination is negative, a message indicating that there is no image to be reproduced and displayed is displayed on the liquid crystal monitor 4 in step S136. Display and return. If step S131 is affirmed, the process proceeds to step S132 to determine whether or not the confidential mode is set. If it is not the confidential mode, only the unencrypted image data is displayed on the liquid crystal monitor 4 in step S133. If there is no unencrypted image data, the same warning as in step S136 is performed and the process returns.

  In the case of the confidential mode, the process proceeds to step S134, and all the encrypted image data is tried to be decrypted with the stored encryption key. In step S135, only the unencrypted image data and the decrypted image data are displayed (image data that could not be decrypted cannot be displayed). Image data that cannot be decrypted is image data captured when an external device 20 different from the external device 20 currently in communication is connected, that is, encrypted with an encryption key corresponding to a different external device 20. Image data. If there is no image data that can be displayed, the same warning as in step S136 is performed and the process returns.

  Here, “display image data” in steps S133 and S135, for example, displays a list of thumbnails corresponding to displayable image data, and corresponds to the selected thumbnail image when one of them is selected. Means the process of displaying the main image.

FIG. 6 shows details of the transfer process (step S15). In step S151, it is determined whether or not image data is recorded on the recording medium 5 in response to an operation for transferring image data to the outside. If the determination is negative, there is no image to be transferred in step S156. Is displayed on the LCD monitor 4 and the process returns. If step S151 is affirmed, the process proceeds to step S152 to determine whether or not the confidential mode is set. If it is not the confidential mode, only the unencrypted image data is transferred in step S153. If there is no unencrypted image data, the same warning as in step S156 is performed and the process returns.
Here, the external device of the transfer destination differs depending on whether the external device for transferring image data and the external device for security function are used together, or the configuration in which both are connected separately.

  In the case of the confidential mode, the process proceeds to step S154, and all the encrypted image data is tried to be decrypted with the stored encryption key. In step S155, only the unencrypted image data and the decrypted image data are transferred. Image data that cannot be decrypted is image data captured when an external device 20 different from the external device 20 currently in communication is connected, that is, encrypted with an encryption key corresponding to a different external device 20. Image data. If there is no image data that can be transferred, the same warning as in step S136 is performed and the process returns.

  Here, “transfer image data” in steps S153 and S155 corresponds to, for example, displaying a list of thumbnails corresponding to displayable image data, and corresponding to the selected thumbnail image when one of them is selected. Means a process of transferring the main image. The decrypted image data may be transferred as it is, or may be encrypted again and transferred. Any one of them may be selected by the user.

  As described above, in this embodiment, when the confidential mode is set by the camera and imaging is performed in a state where communication with a previously registered external device (for example, 20A) is possible, the generated image data is stored in the external device. It is encrypted and recorded with an encryption key corresponding to 20A. Since the encryption key corresponding to the external device 20A cannot be created when the external device is not communicably connected or when other external devices (20B, 20C, etc.) are connected, the external device cannot be created. The image data encrypted with the encryption key corresponding to 20A cannot be decrypted, cannot be displayed as an image, and cannot be transferred to the outside. Similarly, image data captured by connecting the external device 20B or 20C cannot be displayed or transferred by connecting another external device. Therefore, when a single camera is used repeatedly by a plurality of users, the confidentiality of the image between the users can be maintained by performing shooting by connecting each user's own external device so that they can communicate with each other. Each user cannot display or transfer an image captured by another user, but there is no trouble in using the camera. Of course, confidentiality can be maintained when the camera is lost or stolen.

  In addition, in personal authentication forcing password input and specific button operations, etc., there is a risk of forgetting passwords and button operation procedures, or being overlooked by others, but with security functions using external devices like this embodiment, There is no such fear.

  Here, it is desirable to conceal the existence of image data that cannot be decrypted (cannot be displayed) when attempting to display or transfer an image regardless of whether the confidential mode is set. For example, in the thumbnail list display, only thumbnail images of image data that can be displayed or transferred are displayed, and no information regarding the presence or absence of images that cannot be displayed or transferred is displayed. As a result, image data that requires confidentiality is not recognized even by others, and safety is increased.

  Furthermore, each time an external device is connected, an encryption key is created and stored in a volatile memory. Therefore, the encryption key does not remain in the camera when the camera is turned off. Since an encryption key cannot be created without an external device, security is further enhanced. The encryption key once created may be stored in a non-volatile memory corresponding to the external device, and the encryption key may be used thereafter. In this case, the encryption key stored in the volatile memory may be used. It is necessary to make it difficult to remove the key.

DESCRIPTION OF SYMBOLS 1 Shooting lens 2 Imaging element 3 Image processing part 4 Liquid crystal monitor 5 Recording medium 6 Control part 7 Operation part 8 Communication part 20 External apparatus

Claims (6)

A digital camera capable of generating and recording image data by imaging and displaying the recorded image data as an image on a display device,
A communication means for communicating with an external device;
When imaging is performed in a state in which communication with any external device is possible, control means for permitting display on the display device only in a state in which communication with the external device is possible for image data generated and recorded by the imaging And a digital camera. The control means includes
When imaging is performed in a state in which communication with an arbitrary external device is possible, an encryption unit that encrypts image data using an encryption key unique to the external device in the communication enabled state;
When an image display instruction is given in a state in which communication with an arbitrary external device is possible, a decryption unit that decrypts recorded image data using an encryption key unique to the external device in the communicable state;
A control unit that sets the image data successfully decoded by the decoding unit as display target image data,
The digital camera according to claim 1, wherein the encrypted image data can be decrypted only by an encryption key used for the encryption. A digital camera capable of generating and recording image data by imaging and transferring the recorded image data to the outside,
A communication means for communicating with an external device;
When imaging is performed in a state in which communication with an arbitrary external device is possible, control means that permits transfer of image data generated and recorded by the imaging only to an external device only in a state in which communication with the external device is possible A digital camera comprising: The control means includes
When imaging is performed in a state in which communication with an arbitrary external device is possible, an encryption unit that encrypts image data using an encryption key unique to the external device in the communication enabled state;
When an image transfer instruction is made in a state in which communication with an arbitrary external device is possible, a decryption unit that decrypts recorded image data using an encryption key unique to the external device in the communicable state;
The image data that cannot be decoded by the decoding means includes a control unit that prohibits transfer to the outside,
4. The digital camera according to claim 3, wherein the encrypted image data can be decrypted only by an encryption key used for the encryption.   5. The digital camera according to claim 2, wherein the encryption key is created in a state where communication with the external device is possible, and is deleted when the camera is turned off.   6. The digital camera according to claim 1, wherein existence of image data that cannot be decoded by the decoding unit is concealed.

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