JP2006086795A - Digital camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a digital camera capable of surely preventing illegitimate use of the digital camera by other people and browsing of a photographed image by the other people. <P>SOLUTION: The digital camera 10 is provided with a human body information detection section 70 for detecting human body information with respect to a human body of a photographer such as fingerprint information. A registration memory 76 registers in advance the human body information of a possessor of the digital camera 10. The human body information detection section 70 detects the human body information at photographing and the human body information is collated with registered human body information registered in the registration memory 76. When the detected human body information is coincident with the registered human body information, the photographing is permitted and when not coincident, the photographing is inhibited. When the photographing is permitted, an encryption/decryption section 72 uses a prescribed encryption key stored in a key information storage section 74 to encrypt image data of the photographed image and records the encrypted data to a memory card 42. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a digital camera, and more particularly to a digital camera capable of encrypting image data of a captured image.

  In recent years, a conventional silver halide camera has been shifting to a digital camera as a recording means for photographed images. Since an image taken with a digital camera is digital information, it can be easily edited and processed, and can be easily reproduced using a digital camera, a personal computer, or the like. In some cases, the photographed image is not desired to be shown to others. For this reason, various proposals have heretofore been made in order to prevent tampering and reproduction of the captured image by others.

  Patent Document 1 describes a digital camera that encrypts a captured image in order to improve the security of the captured image.

  Patent Document 2 describes a technique in which a hardware key is provided in a digital camera and a personal computer for reproducing images taken with the digital camera in order to prevent use by others.

  Further, in Patent Document 3, in order to prevent unauthorized use by others, a detection means for detecting a fingerprint is provided on a shutter button of a digital camera, and a user is verified by collating the detected fingerprint information with registered fingerprint information. Techniques for identifying are described.

  Patent Document 4 describes a technique for storing a photographer's identification symbol in a memory together with image data to identify the photographer.

Patent Document 5 describes a technique for inputting a password when playing back a shot image and playing back the shot image when the password matches a previously stored password.
JP 2000-299847 A JP 2001-320668 A JP 2002-57928 A JP-A-8-315106 JP 2000-125237 A

  However, none of the above prior arts can strictly prevent unauthorized use of a digital camera by another person and reference of a captured image by another person.

  The present invention has been made in view of the above facts, and an object thereof is to obtain a digital camera that can reliably prevent unauthorized use of a digital camera by another person and reference of a photographed image by another person.

  In order to achieve the above object, the invention described in claim 1 includes a human body information detecting unit that detects human body information at the time of photographing, and a collating unit that collates the detected human body information with registered human body information registered in advance. When the detected human body information and the registered human body information do not match, the prohibiting means for prohibiting shooting, and when the detected human body information and the registered human body information match, the image data of the captured image is encrypted And encryption means for encrypting with a key.

  According to this invention, the human body information detecting means detects the human body information at the time of photographing. In addition, as described in claim 2, the human body information can be configured to be at least one of fingerprint information, retina information, and a face image. In this case, the human body information detecting means can be constituted by a photographing means for photographing at least a part of the photographer's finger, eyes, and face.

  The collating unit collates the detected human body information detected by the human body information detecting unit with registered human body information registered in advance in a memory or the like.

  If the detected human body information and the registered human body information do not match, photographing is prohibited by the prohibiting means. On the other hand, when the detected human body information matches the registered human body information, the image data of the photographed image is encrypted with a predetermined encryption key by the encryption means.

  In this way, human body information such as a fingerprint is registered, human body information is detected at the time of shooting and is compared with the registered human body information, and shooting is permitted and image data of the shot image is encrypted only when they match. Thus, unauthorized use of the digital camera by another person and unauthorized reference of a captured image by another person can be surely prevented.

  In addition, as described in claim 3, it may be configured to further include warning means for warning when the detected human body information does not match the registered human body information. This makes it possible for the photographer to easily recognize that the digital camera cannot be used.

  In addition, as described in claim 4, it may be configured to further include a generation unit that generates the encryption key and a decryption key corresponding to the encryption key based on the human body information detected by the human body information detection unit. . As a result, it is not necessary for the encryption key to register the decryption key in advance, and convenience can be improved.

  In addition, as described in claim 5, the image processing apparatus may further include a decrypting unit that decrypts the image data based on a decryption key corresponding to the encryption key. In this case, it is preferable that the human body information is detected in the same manner as at the time of photographing, the detected human body information and the registered human body information are collated, and decryption is permitted only when the two match. Thereby, it is possible to reproduce the photographed image with the digital camera.

  Further, the human body information may be detected in the same manner as when photographing, the detected human body information and the registered human body information are collated, and the decryption key may be recorded on the external recording medium only when the two match. As a result, the captured image can be reproduced in the external device.

  According to the present invention, there is an effect that unauthorized use of a digital camera by another person and reference of a photographed image by another person can be surely prevented.

  Hereinafter, embodiments of the present invention will be described.

  FIG. 1 shows a block diagram of a digital camera according to an embodiment of the present invention. The photographing optical system 12 of the digital camera 10 includes a photographing lens 14 and a diaphragm 16. The photographic lens 14 is composed of one or a plurality of lenses, and may be a single focal length (fixed focal length) lens or a variable focal length such as a zoom lens or a telephoto / wide-angle bifocal switching lens. Good.

  The subject image formed on the light receiving surface of the CCD 18 via the photographing optical system 12 is converted into signal charges of an amount corresponding to the amount of incident light by each sensor. The signal charge accumulated in this way is read out by a CCD drive pulse applied from the CCD drive circuit 20, and is sequentially output from the CCD 18 as a voltage signal (analog image signal) corresponding to the signal charge.

  The CCD 18 is provided with a shutter drain via a shutter gate, and the accumulated signal charge can be swept out to the shutter drain by driving the shutter gate with a shutter gate pulse. That is, the CCD 18 has a so-called electronic shutter function that controls the accumulation time (shutter speed) of charges accumulated in each sensor by the shutter gate pulse.

  The signal read from the CCD 18 is subjected to correlated double sampling (CDS) processing in the CDS circuit 22 and color separation processing into R, G, B color signals to adjust the signal level of each color signal (pre-white balance). Process).

  The image signal that has undergone the predetermined analog signal processing is applied to the A / D converter 24, converted into R, G, B digital signals by the A / D converter 24, and then stored in the memory 26. .

  A timing signal generation circuit (TG) 28 provides appropriate timing signals to the CCD drive circuit 20, the CDS circuit 22 and the A / D converter 24 in response to a command from the CPU 30, and each circuit generates a timing signal. It is driven in synchronism with a timing signal applied from the circuit 28.

  The CPU 30 is a control unit that performs overall control of each circuit of the digital camera 10, and includes a memory 26, a gain adjustment circuit 34, a gamma correction circuit 36, and a luminance / color difference signal processing circuit (referred to as a YC processing circuit) 38 via a bus 32. , Compression / decompression circuit 40, card interface 44 of memory card 42, display driver 48 for driving display unit 46, human body information detection unit 70, encryption / decryption unit 72, key information storage unit 74, etc. Yes.

  The CPU 30 controls the corresponding circuit block based on the input signal from the operation unit 50, and controls the zooming operation, the automatic focus adjustment (AF) operation of the photographing lens 14, the automatic exposure adjustment (AE), and the like. .

  The operation unit 50 includes a shutter button that gives an instruction to start image recording, a camera mode selection unit, a zoom operation unit, and other various input units. These input means have various forms such as switch buttons, dials, and slide-type knobs. There is also an aspect in which a setting menu or a selection item is displayed on the screen of the touch panel or the liquid crystal monitor display unit, and a desired item is selected with a cursor. . The operation unit 50 may be disposed in the camera body, or may be configured as a remote control transmitter separated from the camera body.

  The CPU 30 performs various calculations such as a focus evaluation calculation and an AE calculation based on the image signal output from the CCD 18, and based on these calculations, driving means (for example, an AF motor or an iris motor) for the photographing lens 14 and the diaphragm 16. Etc.) 52 is controlled to move the focus lens to the in-focus position, and the aperture 16 is set to an appropriate aperture value.

  For example, a contrast AF method in which the focus lens is moved so that the high frequency component of the G signal is maximized is employed for the AF control. In the AE control, the subject brightness (shooting EV) is obtained based on the integrated value obtained by integrating the R, G, B signals of one frame, the aperture value and the shutter speed are determined based on the taken EV, and the driving unit 52 is operated. In addition, the diaphragm 16 is driven, and the charge accumulation time of the CCD 18 is controlled by the electronic shutter so that the determined shutter speed is obtained. Therefore, only by directing the photographic lens 14 of the digital camera 10 toward the subject, optimal exposure adjustment is performed and focusing is automatically performed.

  At the time of shooting and recording, when the shutter button is “half-pressed”, the above-mentioned photometric operation is repeated a plurality of times to obtain an accurate shooting EV, and the aperture value and shutter speed at the time of shooting are finally determined based on this shooting EV. . Then, when the shutter button is “fully pressed”, the aperture 16 is driven so that the final determined aperture value is obtained, and the charge accumulation time is controlled by the electronic shutter so that the determined shutter speed is obtained. In addition to the method of controlling AE and AF based on the image signal acquired from the CCD 18, a well-known photometric sensor, a distance measuring sensor including an AF light projecting / receiving sensor, or the like may be used.

  The digital camera 10 also has a strobe light emitting device 54 and a light receiving element 56 for dimming, and automatically controls the strobe light emitting device 54 when the brightness is low according to the operation of the strobe mode setting button included in the operation unit 50. Are set to “low-brightness automatic light-emission mode” for causing the flash to emit light, “forced light-emission mode” for causing the strobe light-emitting device 54 to emit light regardless of subject brightness, or “light-emission prohibiting mode” for prohibiting light emission of the strobe light-emitting device 54.

  The CPU 30 controls charging of the main capacitor of the strobe light emitting device 54 and discharge (light emission) timing to the light emitting tube (for example, a xenon tube) according to the strobe mode selected by the user, and performs measurement from the light receiving element 56. Based on the result, the emission stop is controlled. The light receiving element 56 receives the reflected light from the subject illuminated by the light emission of the strobe and converts it into an electrical signal corresponding to the amount of light received. The signal of the light receiving element 56 is integrated by an integration circuit (not shown), and the strobe light emission is stopped when the integrated light receiving amount reaches a predetermined appropriate light receiving amount.

  Data output from the A / D converter 24 is stored in the memory 26 and added to the integrating circuit 60. The integration circuit 60 divides the photographing screen into a plurality of blocks (for example, 64 blocks of 8 × 8), and performs integration calculation of the received G signal for each block. Note that the luminance signal (Y signal) may be generated from the R, G, and B data, and the luminance signal may be integrated. Further, the integrating circuit 60 can also be used as an AE arithmetic circuit. Information on the integrated value (calculation result) obtained by the integrating circuit 60 is input to the CPU 30.

  Based on the information from the integration circuit 60, the CPU 30 calculates the evaluation value E of the photographic screen according to a predetermined algorithm, and determines the gain value (amplification factor) in the gain adjustment circuit 34 using the obtained evaluation value E. The CPU 30 controls the gain amount in the gain adjustment circuit 34 according to the determined gain value.

  The R, G, B image data stored in the memory 26 is sent to the gain adjustment circuit 34, where it is amplified. The amplified image data is subjected to a gamma correction process in a gamma correction circuit 36 and then sent to a YC processing circuit 38. The RGB data is converted into a luminance signal (Y signal) and a color difference signal (Cr, Cb signal). Converted.

  The luminance / color difference signal (abbreviated as YC signal) generated in the YC processing circuit 38 is written back to the memory 26. The YC signal stored in the memory 26 is supplied to the display driver 48, converted into a predetermined signal (for example, an NTSC color composite video signal), and output to the display unit 46. As the display unit 46, a liquid crystal display or other display device capable of color display is used. The display unit 46 may be a YC signal input type or an RGB signal input type, and a driver corresponding to the display device is applied.

  The image data is periodically rewritten by the image signal output from the CCD 18, and a video signal generated from the image data is supplied to the display unit 46, whereby the image captured by the CCD 18 is a moving image (live image) in real time. Or not in real time, but displayed on the display unit 46 as a substantially continuous image.

  The display unit 46 can be used as an electronic viewfinder, and the photographer can check the shooting angle of view by using a display image on the display unit 46 or an optical viewfinder (not shown). In response to a predetermined recording instruction (shooting start instruction) operation such as an operation of pressing a shutter button, capturing of image data for recording is started.

  When the photographer inputs a shooting / recording instruction from the operation unit 50, the CPU 30 sends a command to the compression / decompression circuit 40 as necessary, whereby the compression / decompression circuit 40 converts the YC data on the memory 26 into JPEG or another predetermined format. Compress according to The compressed image data is recorded on the memory card 42 via the card interface 44.

  When the mode for recording non-compressed image data (non-compression mode) is selected, the image data is recorded on the memory card 42 without being compressed without performing the compression processing by the compression / decompression circuit 40. The

  In the digital camera 10 of the present embodiment, a memory card 42 is used as means for storing image data. Specifically, a recording medium such as smart media is applied. The form of the recording medium is not limited to the above, and various forms such as a PC card, a micro drive, a multimedia card (MMC), a magnetic disk, an optical disk, a magneto-optical disk, and a memory stick are possible. Corresponding signal processing means and interfaces are applied.

  In the reproduction mode, the image data read from the memory card 42 is decompressed by the compression / expansion circuit 40 and output to the display unit 46 via the display driver 48.

  The human body information detection unit 70 detects human body information related to the human body of the photographer, and detects, for example, the shape of at least a part of a fingerprint, retina, face, and the like.

  For example, when a fingerprint detection device that detects fingerprint information is applied as the human body information detection unit 70, the human body information detection unit 70 can be configured as follows. That is, for example, the shutter button is made of a light-transmitting member, and a light emitting unit for irradiating light from the inside to the photographer's finger touching the shutter button, the photographer's finger touching the shutter button is irradiated A lens that forms an image of reflected light of the reflected light, an image sensor such as a CCD or CMOS sensor that receives the reflected light that has passed through the lens, and an A / D converter that A / D converts the image signal from the image sensor Can be configured. Thereby, the photographer's fingerprint information can be acquired.

  In addition, when a retinal detection device that detects retinal information is applied as the human body information detection unit 70, a light emitting unit for irradiating light from the inside of the photographer's eyes looking through the optical viewfinder of the digital camera 10 is provided. The rest can be configured in the same manner as the fingerprint detection apparatus.

  When a face detection device that detects the shape of a face is applied as the human body information detection unit 70, for example, a small face detection camera for photographing the photographer's face is provided on the back of the digital camera 10. . This face detection camera can also have the same configuration as the fingerprint detection device and the retina detection device.

  The encryption / decryption unit 72 has an encryption function that encrypts image data of a captured image using a predetermined encryption key, and a decryption function that decrypts image data using a predetermined decryption key. As the encryption method, for example, a common key encryption method such as DES (Data Encryption Standard) or a public key encryption method such as RSA (R. Rivest, A. Shamir, L. Adelman) can be used.

  In the common key cryptosystem, the encryption key and the decryption key are the same key. In the public key cryptosystem, the public key to be encrypted or decrypted and the secret key to be decrypted or encrypted are separate keys. . As these encryption key and decryption key, a key generated in advance by the user may be used, or a key generated from registered human body information may be used.

  The key information storage unit 74 stores encryption key used for encryption and decryption key information corresponding to the encryption key.

  The registration memory 76 is a memory for storing human body information of the owner of the digital camera 10. At the time of shooting, the registered human body information registered in the registration memory 76 and the detected human body information detected at the time of shooting are collated, and if they match, shooting is permitted, and if they do not match, shooting is prohibited.

  When the encryption key and the decryption key are generated from the registered human body information, the encryption key and the decryption key are generated and stored in the key information storage unit 74 when the human body information is registered. On the other hand, when a key generated in advance by the user is used, it is necessary to register the key in the digital camera 10 in advance. When registering this key, human body information is detected and registered with the detected human body information. The human body information is collated, and the key registration is permitted only when they match. This prevents unauthorized key registration by others.

  Next, as an operation of the present embodiment, a control routine executed by the CPU 30 will be described with reference to flowcharts shown in FIGS.

  First, a control routine executed by the CPU 30 in the photographing mode will be described with reference to FIG. The control routine shown in FIG. 2 is executed when the power is turned on in the photographing mode for photographing the subject, or when the photographing mode is switched from another mode while the power is turned on.

  It is assumed that human body information of the owner of the digital camera 10 is registered in the registration memory 76 in advance. Registration of human body information can be prohibited, for example, by allowing the registration of human body information only once at the time of purchase of the digital camera 10 and prohibiting the registration thereafter.

  First, in step 100, it is determined whether or not the shutter button has been half-pressed. If the shutter button is not half-pressed, the process waits until the shutter button is half-pressed. If the shutter button is half-pressed, the process proceeds to step 102.

  In step 102, human body information detection processing is performed. That is, when the human body information detection unit 70 is a fingerprint detection device, the human body information detection unit 70 is instructed to capture the photographer's finger touching the shutter button, and the captured image is captured as detected human body information.

  In the next step 104, the registered human body information registered in the registration memory 76 is compared with the detected human body information detected by the human body information detection unit 70, and it is determined whether or not they match. If they match, the process proceeds to step 106, and if they do not match, the process proceeds to step 108.

  In step 106, AE control and AF control are performed. That is, as described above, the aperture value and shutter speed are determined based on the obtained shooting EV, the aperture 16 is driven via the driving means 52, and the charge of the CCD 18 is charged by the electronic shutter so that the determined shutter speed is obtained. Control the accumulation time. Thereby, optimal exposure adjustment is performed.

  Further, the CPU 30 performs various calculations such as a focus evaluation calculation and an AE calculation based on the image signal output from the CCD 18, and controls the driving means 52 of the photographing lens 14 and the diaphragm 16 based on the calculation to focus. While moving the lens to the in-focus position, the aperture 16 is set to an appropriate aperture value. For example, the AF control is performed by a contrast AF method in which the focus lens is moved so that the high-frequency component of the G signal is maximized.

  On the other hand, in step 108, warning processing is performed. Specifically, for example, a warning message for warning that the person is not permitted to use the digital camera 10 is displayed on the display unit 46.

  In step 110, it is determined whether or not the shutter button has been fully pressed. If the shutter button is fully pressed, the process proceeds to step 112. If the shutter button is not fully pressed, the process proceeds to step 114.

  In step 114, it is determined whether or not the half-press of the shutter button is released. If the half-press of the shutter button has not been released, the process proceeds to step 110 to determine whether or not the shutter button has been fully pressed as described above. On the other hand, when the half-press of the shutter button is released, the process proceeds to step 100 and waits until the shutter button is half-pressed again.

  In step 112, an imaging process is performed, and the image data subjected to various processes is temporarily stored in the memory 26.

  In step 114, encryption processing is performed. That is, the image data temporarily stored in the memory 26 is encrypted using the encryption key stored in the key information storage unit 74 and written back to the memory 26.

  In step 118, the encrypted image data stored in the memory 26 is recorded on the memory card 42 via the card interface 44.

  As described above, in this embodiment, human body information such as a fingerprint is registered, human body information is detected at the time of shooting such as when the shutter button is half-pressed and collated with the registered human body information, and shooting is permitted only when they match. In addition, since the image data of the captured image is encrypted, unauthorized use of the digital camera and unauthorized reference of the captured image by another person can be surely prevented.

  Next, a control routine executed by the CPU 30 in the reproduction mode will be described with reference to FIG. The control routine shown in FIG. 3 is switched from the other mode to the playback mode when the power is turned on in the playback mode for playing back the image data recorded on the memory card 42. It is executed when

  First, in step 200, it is determined whether image data to be reproduced is selected by a user operation. If no image data is selected, the process waits until image data is selected. If image data is selected, the process proceeds to step 202.

  In step 202, human body information detection processing is performed. Specifically, when the human body information detection unit 70 is a fingerprint detection device, the display unit 46 displays that fact in order to instruct the user to touch the shutter button halfway and touch it. When the shutter button is half-pressed, the human body information detection unit 70 is instructed to capture a finger, and the captured image is captured as detected human body information.

  In the next step 204, the registered human body information registered in the registration memory 76 and the detected human body information detected by the human body information detecting unit 70 are collated to determine whether or not they match. If they match, the process proceeds to step 206. If they do not match, the process proceeds to step 208.

  In step 206, image reproduction processing is performed. That is, the selected image data is read from the memory card 42, decrypted using the decryption key stored in the key information storage unit 74, and displayed on the display unit 46.

  On the other hand, in step 208, warning processing is performed. Specifically, for example, a warning message for warning that the person is not permitted to use the digital camera 10 is displayed on the display unit 46.

  As described above, in this embodiment, human body information such as a fingerprint is registered, human body information is detected at the time of image reproduction, collated with the registered human body information, and image reproduction is permitted only when there is a match. It is possible to reliably prevent an illegal reference of a photographed image by.

  When referring to a photographed image in an external device such as a personal computer, human body information is collated in the same manner as in the playback mode, and when the detected human body information matches the registered human body information, the decryption key is stored in the memory. What is necessary is just to record on the card | curd 42. As a result, even in an external device such as a personal computer, the captured image can be reproduced using the decryption key recorded in the memory card 42.

It is a block diagram which shows schematic structure of a digital camera. 3 is a flowchart of a control routine executed by a CPU in a shooting mode. 4 is a flowchart of a control routine executed by a CPU in a reproduction mode.

Explanation of symbols

10 Digital Camera 12 Imaging Optical System 18 CCD
30 CPU (verification means, prohibition means, warning means, generation means)
42 memory card 46 display section (warning means)
50 Operation unit 54 Strobe light emitting device 70 Human body information detection unit (human body information detection means)
72 Encryption / Decryption Unit (Encryption Means, Decryption Means)
74 Key Information Storage Unit 76 Registered Memory

Claims (5)

Human body information detecting means for detecting human body information at the time of shooting;
Collation means for collating the detected human body information detected with the registered human body information registered in advance;
Prohibiting means for prohibiting photographing when the detected human body information and the registered human body information do not match,
An encryption means for encrypting image data of a photographed image with a predetermined encryption key when the detected human body information and the registered human body information match;
Digital camera equipped with.   The digital camera according to claim 1, wherein the human body information is at least one of fingerprint information, retina information, and a face image.   3. The digital camera according to claim 1, further comprising warning means for warning when the detected human body information does not match the registered human body information.   4. The generator according to claim 1, further comprising a generating unit that generates the encryption key and a decryption key corresponding to the encryption key based on the human body information detected by the human body information detecting unit. The digital camera according to Item 1.   5. The digital camera according to claim 1, further comprising a decrypting unit configured to decrypt the image data based on a decryption key corresponding to the encryption key.

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