JP2004015284A - Digital camera - Google Patents

Abstract

Provided is a digital camera having a simple interface and capable of wireless data communication with an external device that requests authentication information.
An image pickup unit (10, 20, 30, and 40) for generating image data representing a subject based on an output of an image sensor and image data representing a figure "ABCDE" associated with authentication information of an external device (2). A graphic recognizing unit 10 for recognizing a graphic based on the external device 2 and identifying the authentication information of the external device 2 and a wireless communication unit 50 for performing a modulation / demodulation process for wireless data communication. And wirelessly connected to the external device 2.
[Selection diagram] Fig. 1

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a digital camera.
[0002]
[Prior art]
2. Description of the Related Art Wireless data communication standards such as Bluetooth for realizing wireless data communication between different devices such as digital cameras, printers, mobile phones, and portable information terminals are known. According to the wireless data communication, the trouble of cable connection and the like can be reduced, and for example, it is possible to use the mobile information terminal connected to a communication network using a mobile phone in a bag, thereby improving the usability of the user. .
[0003]
A problem in such wireless data communication is security. For example, it is necessary to prevent a third party from wirelessly connecting to the portable information terminal and referencing data without permission. Therefore, such a problem is generally avoided by performing password authentication in the wireless data communication standard. When password authentication is performed, for example, the printer requests transmission of the password to the portable information terminal that has requested the wireless connection, and rejects the wireless connection from the portable information terminal when the password is invalid, or When a terminal sends data to a mobile phone, etc., it sends the password of the mobile phone to the mobile phone and sends the data after confirming that the mobile phone is the target mobile phone with the password Or you can.
[0004]
[Problems to be solved by the invention]
However, digital cameras generally do not have interfaces such as buttons and switches for the user to input character strings, and external devices such as digital cameras, printers, mobile phones, and personal digital assistants establish wireless connections. When a digital camera requires a password, the digital camera has a problem that it is difficult to wirelessly connect to an external device. For example, when image data is created by a digital camera and the image data is to be transmitted from the digital camera to the printer by wireless data communication, when the printer requests a password for wireless connection, a character string is input to the digital camera. The user cannot enter the digital camera even if he knows the password, and cannot establish a wireless connection with the printer.
[0005]
SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has as its object to provide a digital camera which has a simple interface and can perform wireless data communication with an external device which requests authentication information.
[0006]
[Means for Solving the Problems]
The digital camera according to claim 1, wherein the image pickup means for creating image data representing the subject based on the output of the image sensor, and recognizes the figure based on the image data representing the figure associated with the authentication information of the external device. Figure recognition means for specifying authentication information of an external device, wireless communication means for performing modulation / demodulation processing for wireless data communication, and control means for transmitting authentication information to the external device through the wireless communication means and wirelessly connecting to the external device. , Is provided. According to this digital camera, it is possible to specify the authentication information by creating image data representing a figure associated with the authentication information of the external device by the imaging unit and recognizing the figure represented by the created image data. Thus, the user can input the authentication information of the external device to the digital camera by setting the graphic associated with the authentication information as the subject. Therefore, there is no need to add an interface such as a button or a switch for inputting authentication information to the digital camera, and the interface of the digital camera can be simplified. Further, even when the external device requests the authentication information, by transmitting the specified authentication information through the wireless communication unit, the external device can be wirelessly connected to perform wireless data communication. Therefore, according to this digital camera, wireless data communication with an external device that requests authentication information becomes possible.
[0007]
The digital camera according to the second aspect is characterized in that the control means encrypts the authentication information and transmits it to an external device. According to this digital camera, the security of the authentication information can be improved.
[0008]
In the digital camera according to the third aspect, the external device is a printer that provides a service for printing image data to a device wirelessly connected, and the control unit prints the image data created by the imaging unit via the wireless communication unit. A request is made to a printer as an apparatus. According to this digital camera, when it is desired to print the image data created by the imaging means, the image data can be printed by a wirelessly connected printer by requesting the printing of the image data from an external device through the wireless communication means.
[0009]
In the digital camera according to the present invention, the graphic recognition means recognizes the graphic as a character. According to this digital camera, the authentication information can be represented by characters.
[0010]
In the digital camera according to the fifth aspect, the graphic recognition means recognizes the graphic as a bar code. When the authentication information is represented by a barcode, the authentication information cannot be specified at first glance, and the security can be improved as compared with the case where the authentication information is represented by characters.
[0011]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described based on examples.
FIG. 1 is a diagram schematically illustrating a relationship between a digital still camera 1, a printer 2, and a figure associated with authentication information. Here, the printer 2 is an external device that provides a service for printing image data to a wirelessly connected device. The character string “ABCDE” printed on the authentication information recording paper A is the authentication information of the printer 2, and this character string “ABCDE” corresponds to a figure associated with the authentication information of the printer 2. Although the example of FIG. 1 shows a state in which the authentication information is printed on the authentication information recording paper A, the authentication information may be recorded on a medium other than paper, and may be displayed on a display device such as a CRT. May be performed.
[0012]
FIG. 2 is a configuration diagram of the digital still camera 1 according to one embodiment of the present invention. As shown in the figure, a control unit 10, an imaging unit 20, a driving unit 30, a processing unit 40, a wireless communication unit 50, an operation unit 60, and a display device 70 are provided in the camera body.
[0013]
The control unit 10 includes a CPU 11, a ROM 12, and a RAM 13. The CPU 11 executes a computer program stored in the ROM 12, performs a process of recognizing characters based on image data, a process of transmitting a password and wirelessly connecting to an external device, a process of requesting printing of image data, a predetermined formula , A process of controlling each unit of the digital still camera 1 to create image data, and the like. The ROM 12 stores a computer program for the CPU 11 to execute various processes, a character recognition program for character recognition, a computer program implementing a protocol stack positioned higher than the Baseband layer in the Bluetooth protocol, various data, and the like. Memory. The RAM 13 is a memory for temporarily storing various programs, data, and the like.
[0014]
The function of the “control means” described in the claims corresponds to the function of the control unit 10 transmitting a password and wirelessly connecting to an external device.
The imaging unit 20 includes an optical system and an area image sensor (hereinafter, referred to as an “image sensor”) 23 as an image sensor. The optical system includes a zoom lens 21, an optical stop 22, an optical low-pass filter (LPF), and the like. The zoom lens 21 forms a subject image on a light receiving unit of the image sensor 23 at a preset magnification, and Numeral 22 adjusts the amount of light incident on the image sensor 23. The image sensor 23 accumulates a charge obtained by photoelectrically converting the light received by each photoelectric conversion element for a certain period of time, and outputs an analog electric signal corresponding to the amount of received light to the processing unit 40. As the image sensor 23, a CCD image sensor or a MOS image sensor may be used.
[0015]
The drive unit 30 includes a lens drive unit 31, an aperture drive unit 32, and an image sensor drive unit 33, and controls input and output of the image sensor 23. The lens driving unit 31 drives the zoom lens 21 to realize a zoom function or a focus adjustment function. The aperture driving unit 32 drives the optical aperture 22 to adjust the amount of light incident on the image sensor 23. The image sensor driving unit 33 is an electronic circuit that generates a driving pulse necessary for driving the image sensor 23 and inputs the driving pulse to the image sensor 23.
[0016]
The processing unit 40 includes an analog front end unit 41, a digital image processing unit 45, and a data storage processing unit 46.
The analog front end (AFE) unit 41 includes a correlated double sampling (CDS) circuit 42, an auto gain control (AGC) circuit 43, and an A / D converter 44. The CDS circuit 42 performs a process of reducing noise included in the analog electric signal. The AGC circuit 43 adjusts the level of the analog electric signal by adjusting the gain. The A / D converter 44 quantizes the analog electric signal subjected to each of the above processes into a digital image signal having a predetermined gradation and outputs the image signal. The output image signal is output to the digital image processing unit 45.
[0017]
The digital image processing unit 45 includes a DSP (Digital Signal Processor), and performs gamma correction of the image signal output from the AFE unit 41, interpolation of defective pixels by a pixel interpolation method, correction of white balance, sharpening and compression of the image signal. / Decompression processing, pixel number conversion processing, etc., to create image data representing the subject.
[0018]
The function of the “imaging unit” described in the claims corresponds to the function of the imaging unit 20, the driving unit 30, the processing unit 40, and the function of the control unit 10 that controls these units to create image data.
[0019]
Note that the above various processes performed by the digital image processing unit 45 may be replaced by processes by a computer program executed by the control unit 10.
The data storage processing unit 46 includes a nonvolatile memory. The created image data is stored in the nonvolatile memory. As the nonvolatile memory, for example, a recording medium such as a flash memory, a magnetic disk, and a magneto-optical disk can be used. This non-volatile memory may be detachably connected to the digital still camera 1 body, or may be irremovably connected.
[0020]
The wireless communication unit 50 is configured according to the Bluetooth protocol, and includes a baseband unit 51 and an RF (Radio Specification) unit 52. The baseband unit 51 includes a DSP (Digital Signal Processor), a microcomputer, and the like, implements a function defined by the Baseband layer of the Bluetooth protocol, and performs a process of establishing a physical RF link between the devices. The RF unit 52 includes a D / A converter, a modulator, a demodulator, and the like, implements a function defined by an RF layer of the Bluetooth protocol, and performs data modulation / demodulation processing.
[0021]
The operation unit 60 detects a switch operation by a user and outputs a control signal to the control unit 10. The operation unit 60 includes a power switch for turning on / off the power, a dial switch for switching between an imaging mode and a password input mode, an imaging button for instructing execution of imaging, a zoom button for setting a magnification of a zoom lens, and the like. It has.
[0022]
The display device 70 includes an LCD, an LCD drive circuit, and an encoder. The LCD displays image data by being controlled by the LCD drive circuit, and displays a plurality of detected external device names.
[0023]
The configuration of the digital still camera 1 has been described above. Next, a flow of processing for specifying a password based on a graphic associated with the password will be described.
[0024]
FIG. 3 is a flowchart illustrating a flow of processing for specifying a password based on a graphic associated with the password. This process is started when the imaging button is pressed while the dial switch is switched to the password input mode.
[0025]
When the imaging button is pressed with the character string “ABCDE” of the authentication information recording paper A as a subject, an optical image of the character string “ABCDE” is formed on the image sensor 23 of the imaging unit 20 and correlated with the density of the optical image. The analog electric signal is output to the processing unit 40 (S105). The output analog electric signal is subjected to predetermined processing in the AFE unit 41 and the digital image processing unit 45 of the processing unit 40, and image data representing the character string "ABCDE" is created. The created image data is stored in the data storage processing unit 46 (S110). The CPU 11 of the control unit 10 executes the character recognition program stored in the ROM 12 to perform character recognition based on the image data stored in the data storage processing unit 46 (S115), and converts the recognized character string "ABCDE". It is specified as a password (S120).
[0026]
The function of the “graphic recognition means” described in the claims is a function of the CPU 12 that loads the ROM 12 and the RAM 13 and a character recognition program stored in the ROM 12 into the RAM 13 and executes the same, and specifies a password based on image data. Corresponding to
[0027]
Next, the flow of processing in which the digital still camera 1 requests the printer 2 to print image data will be described.
FIG. 4 is a sequence diagram illustrating a flow of a process of requesting the printer 2 to print image data. In this process, in a state where image data representing an arbitrary subject is stored in the data storage processing unit 46, the digital still camera 1 in an area where wireless connection with the printer 2 can be performed searches for a device compatible with Bluetooth. Started with
[0028]
When the digital still camera 1 searches for a Bluetooth-compatible device in a wirelessly connectable area, the digital still camera 1 detects all searchable external devices compatible with Bluetooth, and mutually detects the Bluetooth with the detected external device. Information indicating the device address is exchanged (S205). The digital still camera 1 outputs a list of device names of the detected external devices including the printer 2 to the display device 70 in a list, and allows the user to select an external device to be wirelessly connected (S210). When the user selects the printer 2 with a predetermined button, the control unit 10 starts a wireless connection with the printer 2 through the wireless communication unit 50 (S215). The wireless connection is performed according to a predetermined protocol specified by Bluetooth, and a random number is transmitted from the printer 2 in the connection process (S220). Upon receiving the random number, the digital still camera 1 calculates an initialization key K _init from the random number, the Bluetooth device address of the digital still camera 1 itself, and the previously specified password “ABCDE” called a PIN code in accordance with a predetermined calculation formula. Thus, the password is encrypted. However, the Bluetooth device address of the digital still camera 1 is not used when the password has a sufficient length (S225). On the other hand, the printer 2 also calculates the initialization key K _{init ′} from the same random number, the previously acquired Bluetooth device address of the digital still camera 1 and the password “ABCDE” called a PIN code owned by the printer 2 according to the same formula. I do. Thus, the password is encrypted. However, the Bluetooth device address of the digital still camera 1 is not used when the password has a sufficient length (S230). Next, the digital still camera 1 and the printer 2 create a link key and transmit an LMP_unit_key or LMP_comb_key message to negotiate which of the created link keys is to be adopted. The digital still camera 1 or the printer 2 transmits an LMP_unit_key message as a link key when a unit key is selected, and transmits an LMP_comb_key message when a combination key is selected. In the LMP_unit_key message, an exclusive OR of the unit key and the initialization key is transmitted. In the LMP_comb_key message, an exclusive OR of the random number generated by the device on the message transmitting side and the initialization key is transmitted. When one device transmits an LMP_unit_key message and the other device transmits an LMP_comb_key message, a unit key is adopted as a link key. When both devices transmit the LMP_unit_key message, the master unit key is adopted as the link key. When both devices transmit the LMP_comb_key message, a combination key is adopted as a link key (S235 and S240). When the link key is determined, the printer 2 transmits a new random number to the digital still camera 1 (S245). When receiving the random number, the digital still camera 1 calculates the response value SRES from the random number, the Bluetooth device address of the digital still camera 1 itself, and the link key determined in accordance with a predetermined calculation formula. The calculation formula here is different from the calculation formulas in S225 and S235 (S250). On the other hand, the printer 2 also calculates the response value SRES 'from the same random number, the previously acquired Bluetooth device address of the digital still camera 1 and the link key according to the same formula (S255). The digital still camera 1 transmits the calculated response value SRES to the printer 2 (S260), and the printer 2 compares the calculated response value SRES 'with the response value SRES transmitted from the digital still camera 1 (S265). Since the link key used for the calculation is the same, the response value SRES 'and the response value SRES match, and the printer 2 permits the wireless connection of the digital still camera 1 and continues the connection processing. Wireless connection with the printer 2 is established (S270). When the connection is established, the digital still camera 1 transmits image data to the printer 2 according to a predetermined Bluetooth protocol, and requests printing of the image data (S275). The printer 2 responds to the request and prints the transmitted image data (S280). On the other hand, when the response value SRES ′ does not match the response value SRES in S275, the printer 2 rejects the wireless connection and the wireless connection is not established.
[0029]
The flow of the process in which the digital still camera 1 requests the printer 2 to print image data has been described above. Once the link key is generated, in the second and subsequent connections, the link key generated last time is used, and therefore, the processes in S220 to S240 are unnecessary. The connection sequence (S215 to S270) is an example of a connection sequence in Bluetooth, and may be another connection sequence defined in Bluetooth. For example, the digital still camera 1 may transmit a random number to the printer 2. Hereinafter, effects of the present embodiment will be described.
[0030]
According to the digital still camera 1 of the present embodiment, when the password of the printer 2 is "ABCDE", image data representing "ABCDE" is created by the imaging means, and "ABCDE" is character-recognized based on the created image data. By doing so, the password of the printer 2 can be specified. Therefore, there is no need to add an interface such as a button or a switch for inputting characters to the digital still camera 1, and the interface of the digital still camera 1 can be simplified. The printer 2 requests a password (response value) encrypted by a predetermined formula for security, but the digital still camera 1 encrypts the specified password as an initialization key, and further encrypts and transmits the password as SRES. By doing so, the printer 2 can be wirelessly connected. Therefore, according to the digital still camera 1, it is possible to perform wireless data communication with the printer 2 which requests a password after conversion by a predetermined formula.
[0031]
Furthermore, according to the digital still camera 1 of the present embodiment, by requesting the printer 2 to print image data through the wireless communication unit 50, the printer 2 can print the image data.
[0032]
In this embodiment, a character string is described as an example of a graphic associated with a password. However, the graphic associated with a password may be a barcode, and even if a password is specified from an identified barcode. Good. Alternatively, a password may be specified by storing a figure having an arbitrary shape and a character in the ROM 12 in association with each other, and recognizing the figure and specifying the character.
[0033]
In the present embodiment, a digital still camera has been described as an example, but the present invention may be applied to a digital video camera.
[Brief description of the drawings]
FIG. 1 is a diagram schematically illustrating a digital camera, an external device, and a graphic associated with authentication information according to an embodiment of the present invention.
FIG. 2 is a block diagram showing a digital camera according to an embodiment of the present invention.
FIG. 3 is a flowchart illustrating a flow of a process in which the digital camera according to the embodiment of the present invention specifies authentication information.
FIG. 4 is a sequence diagram illustrating a flow of a process of requesting printing of image data by a digital camera according to an embodiment of the present invention.
[Explanation of symbols]
1 Digital still camera (digital camera)
10 control unit (imaging means, figure recognition means, control means)
20 imaging unit (imaging means)
30 drive unit (imaging means)
40 processing unit (imaging means)
45 Digital image processing unit (imaging means)
46 data storage processing unit (imaging means)
50 Wireless communication unit 60 Operation unit 70 Display device

Claims (5)

Imaging means for creating image data representing a subject based on the output of the image sensor;
Graphic recognition means for recognizing the graphic based on image data representing the graphic associated with the authentication information of the external device and identifying the authentication information of the external device;
Wireless communication means for performing modulation and demodulation processing for wireless data communication,
A control unit that transmits the authentication information to the external device through the wireless communication unit and wirelessly connects to the external device;
A digital camera comprising: 2. The digital camera according to claim 1, wherein the control unit encrypts the authentication information and transmits the encrypted authentication information to the external device. The external device is a printer that provides a service for printing image data to a wirelessly connected device,
The digital camera according to claim 1, wherein the control unit requests the external device to print image data created by the imaging unit through the wireless communication unit. 4. The digital camera according to claim 1, wherein the figure recognition unit recognizes the figure as a character. 4. The digital camera according to claim 1, wherein the graphic recognition unit recognizes the graphic as a barcode.

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