JP2003296196A - Information storage medium and digital camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an information storage medium having high versatility among various kinds of information equipment for accesses to stored data while retaining data protecting function to illicit access. <P>SOLUTION: In the access to stored data in a memory card 10 from a host equipment side with the memory card 10 installed therein, the unique password of the memory card 10 is confirmed by an access right authentication part 16, whereby each access right (read, write, delete) is given thereto. When the read access right is not given, storage data in storage areas corresponding to each address value are successively read from the storage data in the storage area corresponding to an initial address value, and when the read data quantity reaches a prescribed value, a dummy data output part 18 outputs meaningless dummy data. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information storage medium and a digital camera, and more particularly to an information storage medium in which various kinds of data are rewritably stored in a nonvolatile manner, and a digital camera which stores captured images in the information storage medium.

[0002]

2. Description of the Related Art In a conventional digital camera, image data obtained by shooting a subject image as a still image or a moving image is a flash memory incorporated in the digital camera or a detachable device attached to the digital camera. The data is recorded on a memory card (for example, smart media (SmartMedia (R)), compact flash (CompactFlash), micro drive, etc.) as a recording medium.

However, in general, these memory cards do not have a security management function for restricting access to stored data, and for example, stored information (eg, image data) due to loss or theft of the memory card itself. Is likely to be leaked to others and can be easily duplicated.

To solve this problem, for example, in the technique disclosed in Japanese Patent Laid-Open No. 7-129736,
The memory card has a fixed password authentication function that allows access (read / write / erase) by authenticating the password entered from the outside.

[0005]

However, in the above-mentioned prior art, in order to access the data stored in the memory card, a function of inputting a password for obtaining a data access right from a digital camera or other device is provided. Therefore, a device that does not have such a function cannot access the data stored in the memory card.

Further, in the digital camera to which the above-mentioned prior art is applied, it is possible to prohibit the reading and erasing of data by the above-mentioned password authentication so as to prevent others from erasing the data or copying the data. is there. However, when a memory card to which access rights are set in this way is used in a digital camera that does not have a password input function, which is different from this digital camera, it is possible to record captured images The person cannot read and confirm the photographed image.
Moreover, since the file management information cannot be read out, file management cannot be performed, and for example, a problem may occur in which another file data is erroneously overwritten in the storage area of the stored file data.

[0007] The present invention has been made to solve the above-mentioned problems, and while maintaining a data protection function against unauthorized access, information having high versatility for accessing stored data among various information devices. An object of the present invention is to provide a storage medium and a digital camera capable of reading and writing data from and to the information storage medium as desired.

[0008]

According to a first aspect of the invention, storage means for storing a plurality of data in a non-volatile and rewritable manner, and a read access right to the storage data of the storage means are authenticated. Read authentication means, and access control means for performing read control on the stored data in the storage means based on the authentication result by the read authentication means, and the read access right for the read access right to the stored data in the storage means by the read authentication means. Otherwise, at the time of reading the stored data of the storage means, when the read data amount of the stored data becomes a predetermined amount or more,
Read control means for controlling to output predetermined dummy data.

According to the first aspect of the invention, the storage means stores a plurality of data in a non-volatile and rewritable manner. The read authentication means authenticates the read access right to the data stored in the storage means. Further, the access control means controls the reading of the data stored in the storage means based on the authentication result of the reading authentication means. Further, the read control means, when the read access right to the stored data of the storage means is not authenticated by the read authentication means, when the stored data of the storage means is read, the read data amount of the stored data is equal to or more than a predetermined amount. When it becomes, it is controlled to output predetermined dummy data. Thus, for example, by setting the predetermined amount to a data length including at least information that allows the content of the data to be determined, and allowing a part of reading so that the content can be confirmed, unauthorized data duplication is prevented. can do.

According to a second aspect of the present invention, in the first aspect of the present invention, the storage means does not require authentication of the read access right by the read authentication means at the time of read access to the stored data. An area and a second storage area which requires authentication of a read access right by the read authentication means at the time of read access to the stored data, and a write data amount of the data when writing data to the storage means. Is stored in the first storage area while is less than a predetermined amount, and when the write data amount of the data is equal to or larger than a predetermined amount, writing is controlled to be stored in the second storage area. It is characterized by further including control means.

According to the second aspect of the present invention, the first storage area of the storage means does not require the authentication of the read access right by the read authentication means at the time of read access to the stored data. The data stored in the storage area can be read out regardless of whether or not there is a read access right. On the other hand, the second storage area provided in the storage means requires the read access right authentication by the read authentication means at the time of read access to the stored data, and the data stored in the second storage area has the read access right. Only when authenticated, read operation is possible. Further, the write control means, when writing data to the storage means, stores the write data amount of the data in the first storage area while the write data amount of the data is less than a predetermined amount, and stores the write data amount of the data. When the quantity becomes equal to or more than the fixed quantity, it is controlled to be stored in the second storage area. Thus, for example, by setting the predetermined amount to a data length including at least information that allows the content of the data to be determined, data writing can be performed so that the data content can be confirmed when reading this data, Data protection against unauthorized data reading can be realized.

According to a third aspect of the present invention, there is provided a digital camera for generating image data corresponding to a subject image by photographing, and an interface means for detachably setting the information storage medium according to the first or second aspect. Data for controlling the storage means of the information storage medium to store the image data in a predetermined file format and to obtain the image data already stored in the storage means of the information storage medium via the interface means. And a control means.

According to the third aspect of the invention, the interface means sets the information storage medium according to the first or second aspect of the invention in a detachable manner. Further, the data control means stores the image data corresponding to the subject image generated by photographing in the storage means of the information storage medium in a predetermined file format via the interface means. Further, the data control means controls to acquire the image data stored in the storage means of the information storage medium via the interface means. As a result, the read control means in the information storage medium according to claim 1 or 2 can store the image stored in the storage means when the read access right to the data stored in the storage means is not authenticated by the read authentication means. At the time of data acquisition,
The read data amount of the image data is a predetermined amount (for example,
The data amount corresponding to the header portion including various attribute information of the image data) is controlled to output predetermined dummy data. As a result, if the user does not have the read access right, the data can be read so that at least the content of the image data can be confirmed. Also,
The write control unit in the information storage medium according to claim 1 or 2, wherein the write data amount of the image data is a predetermined amount (for example, a header including various attribute information of the image data when the image data is stored in the storage unit. (The amount of data corresponding to a set) is stored in the first storage area, and when the amount of write data of the image data becomes equal to or more than the predetermined amount, it is stored in the second storage area. To control. As a result, data can be written so that the content of the image data can be confirmed when the image data is read, and data protection against unauthorized data reading can be realized.

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

As shown in FIG. 1, a schematic structure of the memory card 10 according to the present embodiment is shown. The memory card 10 includes a main controller (MC) 12 as a main control unit, a memory 14 for holding data, an access right authentication unit 16, a dummy data output unit 18, and an interface unit (I / F) 20. Has been done.

MC12 is a memory card 10 mounted
Controls exchange of various control signals such as a supply voltage signal, a data signal, a clock signal, and a command signal with a host device (a digital camera 30 described later in this embodiment) applicable as a data recording medium. When the host device accesses the memory card 10, the host device sends an I / F 20 to the MC 12.
Various control signals transmitted via the memory card 1
0, data read access, data write access to memory card 10, and memory card 10
Authentication information for authenticating the execution right (access right) of each access is included in correspondence with each erase access of the data stored in.

The access right authentication unit 16 is for authenticating each of the above access rights based on the above authentication information, and is provided with an authentication password unique to the memory card 10 for each access. Each access (read / write / erase) is executed according to the authentication result for each password.

Examples of the combination pattern of the authentication results of the above passwords include a pattern in which writing / reading is possible and erasing is not possible, a pattern in which reading is possible and erasing / writing is not possible, and the like. Especially, the memory 14
As a pattern set to prevent duplication of the stored data of, there is a pattern in which writing is possible and reading / erasing is not possible. In this case, since the file management information including information about the data amount, data type, storage area address value, etc. of each file stored in the memory card 10 cannot be read out, the host device side cannot store the file management information in the memory card 10. Will not be able to recognize the storage file.

In general, the file management information is often stored near the storage area corresponding to the head address value of the storage area, the amount of data is relatively small such as several tens of kilobytes, and it corresponds to continuous address values. Often stored in storage areas. Utilizing this, the MC 12 according to the present embodiment does not have the read access right to the memory card 10 (for example, the authentication password is not a pattern allowing the read access right, or the authentication password itself cannot be recognized). If there is access from the host device (for the reason (1)), consecutive address values are counted, and the storage area corresponding to the count value less than a predetermined value (for example, a value corresponding to the data amount of several 10 kB as described above) Reading the stored data is permitted, the stored data in the memory 14 is controlled to be output to the I / F 20 via the data bus 22, and the stored data in the storage area corresponding to the count value equal to or larger than the predetermined value is read. For the I / O from the dummy data output unit 18 via the data bus 22.
Output meaningless data to F20. As a result, at least the file management information can be read out even by the host device that does not have the access right to the memory card 10, and the general outline of the data stored in the memory card 10 can be confirmed.

In addition, from the host device to the memory card 1
When writing data to 0, the write data transmitted from the host device to the memory card 10 via the I / F 20 under the control of the MC 12 is stored in the memory 14 via the data bus 22.

The storage area in the memory 14 is divided into a non-authentication area 14A and an authentication area 14B. The non-authentication area 14A is a storage area that is set so that the data held in that area can be accessed as desired, and the authentication area 14B is used when accessing the data held in that area. This is a storage area that requires access right authentication. The non-authentication area 14A corresponds to the first storage area of the storage means of the present invention, and the authentication area 14B corresponds to the second storage area of the storage means of the present invention.

When the data is to be stored in the memory 14, the MC 12 has a predetermined value (for example, a value corresponding to a data amount of several 10 kB as described above) in the data to be stored.
The data amount less than the above is stored in the non-authentication area 14A, and the data amount more than the predetermined value is stored in the authentication area 14B. Therefore, when reading the data stored in this way, at least the file management information can be read by the host device that does not have the access right to the memory card 10 to check the outline of the stored data.

Further, for example, the image data photographed by the digital camera 30 which will be described later as the host device is
Generally, a predetermined compression format (for example, JPEG (Joint
Photographic Experts Group) format etc.) and is recorded after being compressed. In the case of this JPEG file, in addition to the data indicating the main image, the header portion at the beginning of the file stores information of a reduced image of all images called thumbnails, and by acquiring this information, at least that You can check the data contents of the file. Utilizing this, the MC 12 is provided with a function of recognizing the file format of the data stored in the memory 14, and instead of determining the number of consecutive addresses in the data read and write operations, the end of the header part of the JPEG file is terminated. The determination may be made using a flag.

2A and 2B show a schematic structure of a digital camera 30 as the host device to which the memory card 10 according to the present embodiment can be applied. In this digital camera 30, a main body 32 has a substantially box shape, and a grip portion for facilitating the grip of the main body 32 is formed on the left side when viewed from the front.

On the front side of the main body 32, as shown in FIG. 2A, a lens 34 for forming a subject image, a viewfinder 36 for visually confirming the photographing range, and photographing at low illuminance. Strobe for emitting auxiliary light in case of
Is installed.

On the upper surface of the main body 32, on the left side when viewed from the front, one of the operation modes of the digital camera 30 (for example, various photographing modes, photographed image reproduction modes, personal computer output modes, various setup item setting modes, etc.) A mode dial 42 and a power switch 44 used when selecting one of them are provided, and a shutter button 46 is provided at the center of the mode dial 42. Note that the shutter button 46 is configured to be half-pressed to perform AF lock and fully-pressed to perform the image capturing process.

On the right side surface of the main body 32 when viewed from the front,
A slot 40 into which the memory card 10 according to the present embodiment can be loaded is provided, and inside this slot 40, a connector section (not shown) included in a media control section 80 described later is arranged. The memory card 10 loaded in the slot 40 is physically connected to the media control unit 80 via the connector section, so that various data can be exchanged between the media control unit 80 and the memory card 10. It is possible.

As shown in FIG. 2B, the main body 32
A color display 48 composed of a reflective LCD or a transmissive LCD is attached to the lower side of the back surface of the display, and a monochrome liquid crystal display panel 50, a strobe button 52, and a cross are provided above the display 48. Various selection buttons such as a button 54 and a menu execution button 56 are provided.

The display 48 is composed of a liquid crystal display panel in which the display screen size is set to a predetermined number of pixels (for example, 640 × 480 pixels), and when there is an image display instruction, the image to be photographed at the time of photographing is displayed. And an image based on an image file read from a SDRAM (Synchronous Dynamic RAM) 88 and a memory card 10 described later are displayed on the entire screen or a plurality of reduced images are displayed side by side (hereinafter, referred to as thumbnail display). Display various function selection screens.

The liquid crystal display panel 50 displays various set items of the digital camera 30, such as operation mode, image quality, battery amount, strobe light emission / non-light emission, and the number of shootable images.

The cross button 54 is a button for selecting the button displayed on the display 48 or moving the cursor when the display content of the display 48 is the various item selection screen. Further, the strobe button 52 is a button for issuing a forced light emission instruction when the strobe is forcibly fired, or for issuing a light emission prohibition instruction when the strobe 38 is forbidden to emit light, and the menu execution button 56 is a display 48.
Is a button for deciding execution of the item displayed on the screen and selected by the cross button 54.

In the various setup item setting modes described above, the read access right or the erase access right for each image data held in the memory card 10 and the write access right for storing the image data in the memory card 10 are authenticated. It is possible to set a password to do so.

FIG. 3 shows a schematic configuration of a control system of the digital camera 30 described above. The digital camera 30 includes an optical unit 60 including the lens 34, and a CC disposed behind the optical axis of the lens 34.
D62 and the image signal (C
An image signal processing unit 68 for generating predetermined digital image data representing a subject image based on a signal indicating the amount of light received by each of a plurality of photoelectric conversion cells arranged in a matrix on the light receiving surface of the CD 62, and an optical unit. A timing generator 70 for generating timing signals for driving each part of the camera 60 and the CCD 62, a vertical / horizontal driver 64 for driving the CCD 62, and a shutter / iris motor for driving a shutter and diaphragm mechanism included in the optical unit 60. , A drive system driver 66 for each unit of the unit that drives a focus adjustment motor, a zoom motor,
And a main control unit 80 that controls the overall operation of the digital camera 30.

A vertical / horizontal driver 64 and a driver system driver 66 for each unit are connected to the timing generator 70.
0 outputs a timing signal for driving the CCD 62 to the vertical / horizontal driver 64, and outputs a timing signal for driving the mechanical shutter and the diaphragm mechanism provided in the optical unit 60 to each unit drive system driver 66. .

The lens 34 included in the optical unit 60 has a plurality of lenses, and the focal length is changed (variable magnification).
The zoom lens is configured as a zoom lens, and includes a lens driving mechanism (not shown). The zoom motor and the focus adjustment motor are included in this lens drive mechanism, and the zoom motor and the focus adjustment motor are controlled by the main controller 72, and each unit drive system driver 66.
It is driven by the drive signal supplied from. When changing the optical zoom magnification, the main controller 72 controls the drive of the zoom motor to change the focal length of the lens 34 included in the optical unit 60, and the contrast of the image obtained by the CCD 62. The focus control is performed by driving and controlling the focus adjustment motor so that the maximum value is obtained.

The image signal processing unit 68 has a correlation 2 (not shown).
The CCD 6 includes a correlated double sampling circuit (CDS), a gain control amplifier (GCA), and an A / D converter.
The image signal input from the 2 is subjected to correlated double sampling processing by the CDS and R by GCA.
After the sensitivity of each color of GB is adjusted, the digital image data is converted by the A / D converter.

The main control unit 72 has a CPU (Central Processing Unit) 74 for controlling the overall operation of the main control unit 72, a line buffer of a predetermined capacity, and a white balance adjustment circuit (for adjusting white balance variation). WB) and RGB data as YC signals (luminance signal Y, chroma signal C
r, Cb) and an imaging control unit 76 configured to include a Y / C conversion circuit (Y / C), and a compression process for digital image data in a predetermined compression format (for example, JPEG format). The compression / decompression unit 78 that performs decompression processing on the compressed digital image data as well as writing the various information to the memory card 10 and reading the various information written in the memory card 10. The media control unit 80 for controlling and the display 48
LCD control unit 82 for controlling display drive of
And are connected to each other via. Incidentally, various operation button systems 86 including the mode dial 42, the power switch 44, the shutter button 46, the flash button 52, the cross button 54, the menu execution button 56 and the like.
Are connected to the CPU 74, and are configured to be able to transmit respective control signals to the CPU 74.

The bus 84 of the main controller 72 is connected to the SDRAM 88 which mainly stores digital image data obtained by the CCD 62 and a flash ROM 90 which stores various parameters and programs. The CPU 74 can arbitrarily access various data stored in the SDRAM 88 and the flash ROM 90.

In the image pickup control section 76, the digital image data sequentially input from the image signal processing section 68 is accumulated in a built-in line buffer and temporarily stored in the SDRAM 88. The digital image data stored in the SDRAM 88 is read out to the WB under the control of the CPU 74, white balance adjustment is performed, and gamma processing and sharpness processing are performed.
At C, YC signal conversion processing is performed and converted into YC signal data, which is stored in the SDRAM 88 again.

When the shutter button 12 is pressed by the photographer, the YC signal data stored in the SDRAM 88 is compressed by the compression / expansion unit 78, for example, in the JPEG compression format, and then the media control unit. It records on the memory card 10 via 80.

The pixel signal processing unit 68, the timing generator 70, and the main control unit 80 are a one-chip LSI.
(Large Scale Integrated circuit), the size, the reliability, and the cost of the digital camera 30 are reduced.

Next, the operation of this embodiment will be described.

In the memory card 10 according to the present embodiment, the processing routine shown in FIG. 4 is executed in the MC 12 when reading data.

First, in step 100, the read access right is authenticated. By confirming the password unique to the memory card 10 by the access right authentication unit 16, each access right (read / write / erase) is given.

At the next step 102, it is judged whether or not there is a read access right. If the judgment is affirmative, the routine proceeds to step 104, where a normal read operation is carried out to end this processing routine, and a negative judgment is made. If so, step 106
Then, the process proceeds to and the stored data in the storage area corresponding to the initial address value is read.

At the next step 108, it is judged whether or not the read data amount has reached a predetermined value, and if the judgment is negative, the routine proceeds to step 110, where the stored data in the storage area corresponding to the next address value is stored. Read and perform step 108 above.
On the other hand, when the determination is affirmative, the process proceeds to step 112, the dummy data output unit 18 outputs meaningless dummy data, and the present processing routine ends.

As a result, at the time of reading data, the data protection function for preventing illegal data duplication is maintained even when there is no read access right to the data stored in the memory card 10 or a device which cannot recognize the password. At the same time, the data can be read so that the data content can be confirmed.

Further, the memory card 1 according to the present embodiment
At 0, when writing data, at MC 12, FIG.
The processing routine shown in is executed.

First, in step 200, the non-authentication area 1
Data is written in the storage area corresponding to a predetermined write start address value in 4A.

In the next step 202, it is judged whether or not the write data amount has reached a predetermined value, and in the case of a negative judgment, the routine proceeds to step 204, in the non-authentication area 14A corresponding to the next address value. The data is written in the storage area, and the process returns to step 202. On the other hand, if the determination is affirmative, the process proceeds to step 206, the data is written in the authentication area 14B, and this processing routine ends.

Thus, at the time of writing data, the data content can be confirmed even when there is no read access right to the data stored in the memory card 10 or when the data is read by a device which cannot recognize the password. can do.

As described above, according to the memory card of the present embodiment, even when there is no read access right or write access right to the data stored in the memory card, or even in a device which cannot recognize the password. , By allowing the data to be read and written with a restriction so that the content of the data can be confirmed, it can be used as a highly versatile data recording medium while maintaining the data protection function for preventing illegal data duplication. .

[0053]

As described above, according to the present invention,
When the read access right to the storage data of the storage means is not authenticated, when the storage data of the storage means is read, a predetermined dummy data is output when the read data amount of the storage data becomes a predetermined amount or more. At the same time, at the time of writing data to the storage means, while the write data amount of the data is less than a predetermined amount, the read access right authentication by the read authentication means is not required at the time of read access to the stored data. The data is stored in the storage area, and when the write data amount of the data becomes equal to or more than a predetermined amount, the read data is stored in the second storage area which requires authentication of the read access right by the read authentication means at the time of read access to the stored data. I decided to do so,
An information storage medium having high versatility among various information devices for accessing stored data while maintaining a data protection function against unauthorized access, and a digital camera capable of reading and writing data from and to the information storage medium as desired. It has an excellent effect that it can be provided.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a memory card according to an embodiment of the present invention.

FIG. 2A is a perspective view showing the outer appearance of the front side of the digital camera according to the embodiment of the present invention, and FIG.
It is a perspective view showing the appearance of the back side of the digital camera.

FIG. 3 is a schematic configuration diagram of a control system of the digital camera according to the embodiment of the present invention.

FIG. 4 is a flowchart showing a flow of data read processing according to the embodiment of the present invention.

FIG. 5 is a flowchart showing a flow of data writing processing according to the embodiment of the present invention.

[Explanation of symbols]

10 memory card 12 Main controller 14 memory 14A Non-certified area 14B authentication area 16 Access Right Authentication Department 18 Dummy data output section 20 Interface section 22 Data bus 30 digital camera 32 Optical unit 34 Operation button system 36 LCD 38 slots 40 CCD 46 pixel signal processing unit 50 Main control unit 52 CPU 54 Imaging control unit 56 Media control unit 58 compression / expansion section

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 5/91 H04N 101: 00 // H04N 101: 00 5/91 P F term (reference) 5B017 AA03 AA06 BA05 BA06 BA09 CA14 CA16 5B058 CA27 KA08 KA31 YA20 5C022 AA13 AB15 AB23 AB29 AC03 AC12 AC16 AC32 AC42 5C052 AA17 CC01 CC11 DD02 GA02 GA03 GA06 GB06 GC05 GE06 GF00 5C053 FA08 FA27 GA11 GB36 JA21 LA01 LA06

Claims (3)

[Claims] 1. A storage unit that stores a plurality of data in a non-volatile and rewritable manner, a read authentication unit that authenticates a read access right to the stored data of the storage unit, and an authentication result by the read authentication unit. Access control means for controlling the read of the stored data of the storage means based on the above, and when the read access right to the stored data of the storage means is not authenticated by the read authentication means, when the stored data of the storage means is read 2. An information storage medium, comprising: read control means for controlling to output predetermined dummy data when the read data amount of the stored data becomes equal to or larger than a predetermined amount. 2. The first storage area, wherein the storage means does not require the authentication of the read access right by the read authentication means at the time of read access to the stored data, and the read access by the read authentication means at the time of read access to the stored data. A second storage area that requires authorization of rights;
When the data is written to the storage means, the data is stored in the first storage area while the write data amount of the data is less than a predetermined amount, and the write data amount of the data is not less than the predetermined amount. 2. The information storage medium according to claim 1, further comprising a write control unit that controls to store the data in the second storage area when the storage capacity is reached. 3. A digital camera for generating image data corresponding to a subject image by photographing, the interface means for detachably setting the information storage medium according to claim 1 or 2, and the interface means. A data control means for controlling the storage means of the information storage medium to store the image data in a predetermined file format and to obtain the image data already stored in the storage means of the information storage medium. camera.