JPH0774994A - Electronic still camera device - Google Patents

Abstract

PURPOSE:To prevent the generation of a data erasing accident due to user's misoperation by using an inexpensive EEPROM card for an electronic still camera device. CONSTITUTION:This electronic still camera consists of a camera body 2 and a memory card 4 loaded to the body 2 through a connector 3 so as to be optionally loaded/ejected. The memory card 4 is provided with an EEPROM 15 having a data management area 17 and a data area 18, an EEPROM 16 having a data area 19 and a data I/O control circuit 13. The camera body 2 is provided with a DRAM 7 having almost the same constitution as the areas 17 to 19 and a data I/O control. circuit 9 for transferring data to the memory card 4 while storing the data of respective areas in the DRAM 7 by the transfer of instructions to/from the circuit 13.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic still camera device for storing image data in a memory card or the like.

[0002]

2. Description of the Related Art In recent years, an electronic still camera device has been attracting attention as a new video device to replace a film type camera device. However, a user's erroneous operation may cause loss of data (image data) obtained by imaging a subject. Therefore, improvement is desired.

In general, an electronic still camera device comprises a camera body and a memory card which is inserted into and removed from the camera body, and image data obtained by the camera body is stored in the memory card. This memory card has an SRAM as a semiconductor memory for storing image data.
(Static random access memory) and EE
PROM (Electrically Erasable and
Programmable read only memory) is applied, but each has its own advantages and disadvantages.

Here, referring to FIG. 2, advantages of a memory card (SRAM card) to which SRAM is applied and a memory card (EEPROM card) to which EEPROM is applied.
Explain the disadvantages.

As shown in the figure, with respect to the backup battery and the cost of the comparison items 1 and 2, the SRAM card has a demerit that the cost is high because the backup battery is required, whereas the EEPROM card does not require the backup battery. Therefore, there is an advantage that the cost is low.

Regarding the write speed and read speed of the following comparison items 3 and 4, the SRAM card has only the random access mode, while the EEP.
Although the ROM card has a random access mode and a page mode, the SRAM card is faster than the EEPROM card in each speed in the random access mode.

Further, the erase (erase) mode of the comparison item 5 is a mode peculiar to the EEPROM card, and the SRA
This mode does not exist in the M card. That is, EE
In a PROM card, data is already stored in a certain storage area of the EEPROM, and when storing new data in that storage area, it is necessary to erase the previously stored data once and then store the new data. There is.

The write verification of the final comparison item 6 is a process peculiar to the EEPROM card and is a process which does not exist in the SRAM card. That is, EEPRO
In the M card, when the writing process is performed on a predetermined data area in the EEPROM, the data is often not completely written in one time. Therefore, the EEPR
The write verify is a process of reading the content stored in the OM each time to check the accuracy. If there is a write failure due to this write verify, data is written again in another relief area. At this time, management information is used as information for managing storage destinations such as a relief area and a data area.

In view of the above advantages and disadvantages, SRA
Since the EEPROM is cheaper than the M, the EEPROM card is often used in the electronic still camera device in recent years.

By the way, when a user handles an electronic device,
Not only this electronic still camera device but also an operation error occurs. For example, if the memory card is inserted into the camera body and the user removes the memory card while transferring image data from the camera body to the memory card (when the line is hot-plugged), the power supply from the camera body side is cut off ( Will be stopped). This is the same when the user accidentally turns off the power switch on the camera body side.

In this case, if the memory card is an SRAM card, a backup battery is provided, so that only the image data being written is lost.

However, when the memory card is an EEPROM card, all the data may be lost because the backup battery is not provided and there is the erase mode. Even if some of the image data barely remains, if the management information indicating the storage destination of the image data is lost, it will not match the management information on the camera body side when the write verify is executed, so a new image In some cases, the data cannot be written and all the data in the electronic still camera device cannot be read out to the EEPROM card side.

[0013]

As described above, in the above-described conventional electronic still camera device, when the power supply to the semiconductor memory is stopped due to an operation error on the user side, an inexpensive semiconductor memory, that is, an EEPROM is used for the memory card. However, there is a problem that all the data in the electronic still camera device may become unreadable.

The present invention has been made in order to solve such a problem, and prevents the image data from becoming unreadable due to an operation error on the user side while using an inexpensive memory card to which an EEPROM is applied. An object is to provide an electronic still camera device.

[0015]

In order to achieve the above-mentioned object, an electronic still camera device of the present invention stores image data of a subject imaged by a camera body in a data area of an EEPROM and manages the image data. In an electronic still camera device for storing management information for controlling in an EEPROM management information area, data input / output means for transmitting and receiving the image data and the management information between the camera body and the EEPROM, and the camera body are provided. And a data storage means having a storage area configured substantially the same as the data area and the management information area of the EEPROM, and the data storage means when new image data is transferred to the EEPROM by the data input / output means. The management information and the E stored in the means side
A means for comparing the management information stored in the EPROM side, and as a result, if there is undefined management information on the data storage means side, copying the undefined management information to the management information area of the EEPROM. It is equipped with.

[0016]

According to the present invention, the data storage means of the camera body is provided with the data area and the management information area having substantially the same structure as the EEPROM, and the management information is also stored when the image data is stored in the data area. When this image data is transferred to the EEPROM, the management information on the data storage means side is compared with the management information on the EEPROM side. As a result, if there is undefined management information on the data storage means side, the undefined The management information is copied to the management information area of the EEPROM.

Therefore, even if the power supply to the EEPROM is stopped due to an operation error on the user side during the transfer of the image data, a part of the image data being transferred is lost but the management information for managing the image data is used as a basis. Then, the image data can be read from the EEPROM.

This prevents image data from becoming unreadable even if an operation error is made on the user side while using an inexpensive EEPROM card.

[0019]

Embodiments of the present invention will now be described in detail with reference to the drawings.

FIG. 1 is a diagram showing an electronic still camera device according to an embodiment of the present invention.

In the figure, 1 is an electronic still camera device. This electronic still camera device 1 is configured. The camera body 2 has a CCD (CHA
GE / COUPLED / DEVICE) 5, a DRAM (Dynamic Random Access Memory) 7 for storing image data from the CCD 5 via the bus line 6, and image data via the bus line 6 and the bus line 8 And a data input / output control circuit 9 for inputting and outputting.
The DRAM 7 is provided with storage areas such as a data area 10 and a data management area 11. The connector 3 has data to be written from the camera body 2 to the memory card 4,
Address data indicating the writing location is supplied.

On the other hand, in the memory card 4, a data input / output control circuit 13 for performing data input / output through the bus line 8 using the high speed buffer memory 12, and a bus line for the data input / output control circuit 13. A plurality of EEPROMs (Electrically Erasable and Programmable Read Only Memory) 15, 16 connected to each other through a semiconductor memory group are provided. The EEPROM 15 has a data management area 1
7 and a data area 18 are provided, and the EEPROM 16 is provided with a data area 19.

Next, the operation of this electronic still camera device will be described.

In this electronic still camera device, when the memory card 4 is inserted into the connector 3, the data input / output control circuit 9 is connected to the data input / output control circuit 13 of the memory card 4 by the bus line 8 and the connector 3. Through EEP
An instruction is issued to output the data (management information) in the data management area 17 of the ROM 15. When the data input / output control circuit 13 receives this command, the data input / output control circuit 13 reads the data (management information) from the data management area 17, temporarily stores it in its own high-speed buffer memory 12, and then stores this data (management information). ) Is output to the data input / output control circuit 9 on the camera body 2 side.

When the data input / output control circuit 9 receives this data (management information), this data (management information) is DR
It is stored in the data management area 11 of AM7. Then, the data input / output control circuit 9 analyzes the management information stored in the data management area 11, and completes the preparation for writing new image data in the memory card 4. At this time, if the management information does not exist in the memory card 4, the user is prompted to initialize or not. Then, upon initialization, the camera body 2 and the memory card 4 are initialized, new management information is created, and the management information is stored in the data management areas 11 and 17 of the camera body 2 and the memory card 4, respectively.

After the preparation is completed, when the electronic still camera device 1 is aimed at a subject and a shutter (not shown) is pressed, an image of the subject at that time is picked up by the CCD 5 and the image data is output through the bus line 6. And is stored in the data area 10 of the DRAM 7. Then, the data input / output control circuit 9 determines the data area 18 in the memory card 4 based on the management information stored in the data management area 11.
19 is selected and the address data for data writing and its control data are output to the data input / output control circuit 13. After that, the data input / output control circuit 9 outputs the image data stored in the data area 10 of the DRAM 7 to the high-speed buffer memory 12 by a fixed amount that can be temporarily held. If the high-speed buffer memory 12 has a sufficient capacity, the image data is output at one time.

The data input / output control circuit 13 in the memory card 4 which has received the address data and the control data thereof stores the image data temporarily held in the high speed buffer memory 12 in the data area (of the EEPROM 15) designated by the address data. Data area 18 or EEP
Write to the data area 19) of the ROM 16. Then, the data input / output control circuit 13 performs a verify process with the contents of the high speed buffer memory 12, and writes the image data if there is no defect in the image data.

After that, the data input / output control circuit 13 reads the management information of the data management area 17 in the memory card 4 into the high speed buffer memory 12 by the above-mentioned method, changes the management information according to the current state, and changes the management information. Is written in the data management area 17.

At this time, the data input / output control circuit 13 performs the verify process in the same manner as described above, further changes the management information when a defect occurs, and if necessary, the EEPROM 1
5 or a new data management area is set in the EEPROM 16 and the changed management information is written. After that, the data input / output control circuit 13 notifies the data input / output control circuit 9 on the camera body 2 side of the end.

Upon receiving this notification, the data input / output control circuit 9 immediately receives the high speed buffer memory 1 in the memory card 4.
The management information of No. 2 and the management information of this side (data management area 11) are compared, and if there is a change due to a defect or the like, the management information of the data management area 11 is changed and a writing operation for new image data is performed. finish.

Here, there are two cases when the memory card 4 is removed from the camera body 2 during execution of the above-mentioned processing operation, that is, image data is being written (a) or subsequent management information is being written / changed (b). ) Etc. are explained.

First, a case (a) in which the memory card 4 is removed while the image data is being written from the camera body 2 to the memory card 4 will be described.

When the memory card 4 is inserted, the transfer processing of the image data is immediately performed. Therefore, the high speed buffer memory 12 of the memory card 4 and the data area 18 in the EEPROM 15 or the data area 19 in the EEPROM 16 are transferred.
At least the image data is written in. When the memory card 4 is removed, the power supply from the camera body 2 to the memory card 4 is stopped.

In this case, the image data written in the high speed buffer memory 12 is instantly removed and the EEPROM 1
Although a part of the image data is written in the data area 18 in 5 or the data area 19 in the EEPROM 16, the management information corresponding to the image data remains unchanged. In addition, the data area 10 on the camera body 2 side
There is no change in all the image data of. Therefore, when the memory card 4 is inserted again, the management information in the data management areas are compared with each other, and the data area 18 or the data area 19 corresponding to the matched management information is replaced with the data area 1
Since the image data of 0 is transferred from the beginning, the image data is stored in the memory card 4 without any trouble, and the loss of the image data is avoided. The image data partially left in the data area 18 or the data area 19 is erased.

Next, a case (b) in which the memory card 4 is removed while writing and changing the management information after writing the image data will be described.

In this case, when the power supply is stopped, the management information in the data management area 17 of the memory card 4 is completely erased at worst. However, since the management information in the data management area 11 on the camera body 2 side does not change, when the memory card 4 is inserted again, the management information in the data management areas are compared with each other. Then, when there is no management information in the data management area 17 on the memory card 4 side, that is, when the management information becomes indefinite, the management information in the data management area 11 is copied to the data management area 17 on the memory card 4 side. After copying, the management information and the data area 18 of the EEPROM 15
And the usage status of the data area 19 of the EEPROM 16 is confirmed, and if they match, the data area 18 and the data area 19 of the memory card 4 designated by the individual management information are held in the data area 10 of the camera body 2. Since the new image data is newly transferred, the loss of the management information and the image data is avoided at this time as well.

Further, the data input / output control circuit 9 of the camera body 2 stores the management information held on the camera body 2 side,
Before verifying the management information held on the memory card 4 side, if the data input / output control circuit 9 is controlled so that the power supply to the camera body 2 is not stopped, the data is lost due to an erroneous operation of a power switch (not shown). Can be avoided.

When the memory card 4 is initialized, the management information held in advance on the memory card 4 side is copied to the data management area 11 of the camera body 2 before initialization, and then the memory card 4 is initialized. Data management area 11
The data input / output control circuit 9 extracts only the defect information of the memory card 4 from the copied management information, erases the other data, and copies the extracted defect information to the initialized memory card 4 to obtain the defect information. It is possible to initialize the memory card 4 while leaving only that, and it is possible to prevent the verification process due to the initialization from being repeated.

As described above, according to the electronic still camera device of this embodiment, the semiconductor memories are EEPROMs 15 and 1,
Even when the user makes an erroneous operation during data transfer, for example, by removing the hot line or turning off the power switch, and the power supply to the memory card 4 is stopped using the memory card 4 to which No. 6 or the like is applied, the camera body 2 Since the management information and image data are backed up in the DRAM 7 of the above, after inserting the memory card 4 or starting the power supply,
Imaged image data is stored in the EEPROM of the memory card 4
It is possible to prevent the image data from being lost by copying the image data to 15, 16 or the like. As a result, as a memory card for an electronic still camera device, EEPRO, which is less expensive than SRAM,
The M card can be used similarly to the SRAM card.

[0040]

As described above, according to the present invention, EEPRO is caused by an operation error on the user side during the transfer of image data.
When the power supply to M is stopped, the image data being transferred is erased from the EEPROM, but the management information for managing the image data remains in the camera body side, and the image is copied by copying the management information to the EEPROM. Since the data can be read, the image data does not become unreadable due to an operation error on the user side even when an inexpensive EEPROM is used.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an electronic still camera device according to an embodiment of the present invention.

FIG. 2 shows a case where S is used when a conventional electronic still camera device is used.
FIG. 6 is a diagram comparing the advantages and disadvantages of a RAM card and an EEPROM card.

[Explanation of symbols]

1 ... Electronic still camera device, 2 ... Camera body, 3 ... Connector, 4 ... Memory card, 5 ... CCD, 6, 8 ... Bus line, 7 ... DRAM, 9 ... Data input / output control circuit on camera body side, 12 ... High-speed buffer memory, 13 ... Data input / output control circuit on memory card side, 15, 16 ... EEPR
OM.

Continuation of front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location G06K 19/07

Claims (1)

[Claims] 1. Image data of a subject imaged by a camera body is stored in a data area of an EEPROM, and management information for managing the image data is stored in the EE.
In an electronic still camera device for storing in a management information area of a PROM, data input / output means for transmitting and receiving the image data and the management information between the camera body and the EEPROM, and the data of the EEPROM provided in the camera body. Area and a storage area having a storage area configured almost the same as the management information area, and new image data is stored in the E area by the data input / output means.
When transferred to the EPROM, the management information stored in the data storage unit side is compared with the management information stored in the EEPROM side, and as a result, there is undefined management information on the data storage unit side. In this case, the electronic still camera device further comprises means for copying the indefinite management information into the management information area of the EEPROM.