JP2006190030A - Data processor and data processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To realize sure execution of deletion of unnecessary data and shortening of the time required for recording data according to the use state of a flash memory. <P>SOLUTION: The data processor for recording data in a storage medium having a data recording area for recording the data and a management area of a file system comprises a logical format means logically formatting the file management area; a data deletion means electrically deleting data stored in the data recording area of the storage medium by a predetermined size; and a physical format means executing the logical format and the deletion of the data recording area together according to the deleted state by the data deletion means. At the time of formatting, bench mark measurement is performed, and physical format is executed only when the physical format is valid. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a data processing apparatus and a data processing method, and more particularly to a technique suitable for use in a data recording apparatus that processes image data such as a digital camera.

  As recording media for digital cameras and the like, flash memories such as compact flash (registered trademark) and SD (Secure Digital) memory cards are widely used. The flash memory is characterized by being non-volatile and capable of repeatedly erasing and writing data. Data erasure and writing in the flash memory are executed in units of a certain size called a block constituting the flash memory.

  For example, when data is rewritten to a block in which data has already been written, the previous data is erased for the block size, and all data is electrically cleared before new data is written. Processing is in progress. On the other hand, if it is an erased block, it is only necessary to write new data for the block size.

  In addition, since the above flash memory is also used in various information devices such as personal computers, a file system such as FAT (File Allocation Table) is generally constructed. Therefore, the flash memory can be logically distinguished into a management area for the file system and a data area where data actually exists.

  For example, when storing image data with a digital camera or the like, the vacancy of the data area is searched from the management information in the management area, the vacant part is recorded as used, and the actual image data is recorded in the data area. Like to do.

  Contrary to the case of saving, when deleting or formatting image data, the image data in the data area itself is not erased as it is, and the image data in the management area corresponds to the corresponding part or format. In the case of, it is often processed only by leaving the usage status of all parts empty.

  For this reason, for example, as shown in Patent Document 1, due to the nature of the flash memory, writing to an already erased block is faster than erasing than writing to an already written block. Can write. However, when writing is performed by this method, previous image data is often written in a logical data area where data is actually written, even though data is deleted or formatted.

  For this reason, in situations where high-speed writing such as continuous shooting or high-definition moving images is required for a flash memory in such a state, it takes a long time to record image data. There is a point.

  In addition, since data remains in the data area, there is a possibility that previous data may be restored in an unintended scene by using restoration software, etc. There seems to be a problem.

  Since the erasing process takes time in proportion to the capacity, if the erasing process is performed on the flash memory whose capacity is increased, the erasing process itself takes a lot of time. In other words, in order to efficiently use the flash memory and protect the image data, how to efficiently erase the data in the data area has been a big issue.

JP 2003-224809 A

  In order to solve such a problem, the technique proposed in Patent Document 1 searches for an empty data area portion from the availability of the management area of the file system, and erases the empty portion in advance. The method of doing is done. However, it is not completely guaranteed whether the correspondence between the size of the logical empty portion and the physical block size can be reliably obtained.

  Therefore, if the correspondence between the size of the logical vacant part and the physical block size cannot be taken, can the necessary data and the data to be erased exist on the same block, and cannot be erased itself? Or, there was a possibility that necessary data was deleted accidentally.

  Further, when the area to be erased is enormous, the response to the user is insufficient. That is, in a digital camera, it is desirable to respond immediately to the user's operation at the moment when the user wants to shoot. However, if it takes a long time to erase the data, there is a problem that the timing at which the user wants to take a picture is missed.

  In view of such a problem, the present invention provides both a flash memory capable of reliably erasing unnecessary data and a time required for recording image data. It is aimed to be able to be realized according to the usage situation of.

  A data processing apparatus of the present invention is a data processing apparatus for recording the data on a recording medium having a data recording area for recording data and a management area of a file system, wherein the file management area is logically Logical formatting means for performing formatting, data erasing means for electrically erasing data recorded in the data recording area of the storage medium by a predetermined size, and the logical format according to the erasing state of the data erasing means, And physical formatting means for executing erasure of the data recording area.

  A data processing method of the present invention is a data processing method for recording the data on a recording medium having a data recording area for recording data and a management area of a file system, wherein the file management area is logically A logical formatting step for performing formatting, a data erasing step for electrically erasing data recorded in a data recording area of the storage medium by a predetermined size, and the logical formatting according to the erasing state of the data erasing step. And a physical formatting step for executing erasure of the data recording area.

  A computer program according to the present invention is a program for causing a computer to execute a data processing method for recording the data on a recording medium having a data recording area for recording data and a management area of a file system. According to a logical formatting process for logically formatting the area, a data erasing process for electrically erasing data recorded in the data recording area of the storage medium by a predetermined size, and an erasing state of the data erasing process The computer is caused to execute a physical formatting step for executing the logical format and erasing the data recording area together.

  The recording medium of the present invention records the computer program described above.

  According to the present invention, the optimum format is automatically determined when the flash memory is initialized, and initialization is performed using the determined format. Therefore, the necessary data and the data to be erased are in the same block. It is possible to prevent as much as possible that the data exists above and cannot be erased or that necessary data is erased by mistake. When high speed is required, the time required for recording data can be shortened. Thereby, for example, it is possible to sufficiently respond to a request for high-speed continuous shooting when used in an imaging apparatus and a request for writing a high-definition moving image at high speed.

(First embodiment)
Embodiments of the present invention will be described below with reference to the drawings.
FIG. 1 is a diagram showing a configuration of an embodiment of the present invention. In FIG. 1, reference numeral 100 denotes a digital camera.

  Reference numeral 10 denotes a photographing lens, 12 denotes a shutter having a diaphragm function, 14 denotes an image sensor that converts an optical image into an electrical signal, and 16 denotes an A / D converter that converts an analog signal output from the image sensor 14 into a digital signal. A timing generation circuit 18 supplies a clock signal and a control signal to the image sensor 14, the A / D converter 16, and the D / A converter 26, and is controlled by the memory control circuit 22 and the system control circuit 50.

  An image processing circuit 20 performs predetermined pixel interpolation processing and color conversion processing on the data from the A / D converter 16 or the data from the memory control circuit 22. Further, the image processing circuit 20 performs predetermined calculation processing using the captured image data, and the system control circuit 50 controls the exposure control means 40 and the distance measurement control means 42 based on the obtained calculation result. TTL (through-the-lens) AF (autofocus) processing, AE (automatic exposure) processing, and EF (flash pre-flash) processing. Further, the image processing circuit 20 performs predetermined arithmetic processing using the captured image data, and also performs TTL AWB (auto white balance) processing based on the obtained arithmetic result.

  A memory control circuit 22 controls the A / D converter 16, the timing generation circuit 18, the image processing circuit 20, the image display memory 24, the D / A converter 26, the memory 30, and the compression / decompression circuit 32.

  The data of the A / D converter 16 is written into the image display memory 24 or the memory 30 via the image processing circuit 20 and the memory control circuit 22 or the data of the A / D converter 16 is directly passed through the memory control circuit 22. It is. Reference numeral 24 denotes an image display memory, 26 denotes a D / A converter, and 28 denotes an image display unit composed of a TFT LCD or the like. Display image data written in the image display memory 24 passes through the D / A converter 26. Displayed by the image display unit 28.

  If the image data captured using the image display unit 28 is sequentially displayed, the electronic viewfinder function can be realized. The image display unit 28 can arbitrarily turn on / off the display according to an instruction from the system control circuit 50. When the display is turned off, the power consumption of the digital camera 100 can be significantly reduced. it can.

  Reference numeral 30 denotes a memory for storing captured still images and moving images, and has a sufficient storage capacity to store a predetermined number of still images and a predetermined time of moving images. This makes it possible to write a large amount of images to the memory 30 at high speed even in continuous shooting or panoramic shooting in which a plurality of still images are continuously shot. The memory 30 can also be used as a work area for the system control circuit 50.

  Reference numeral 32 denotes a compression / decompression circuit that compresses and decompresses image data by adaptive discrete cosine transform (ADCT) or the like, reads an image stored in the memory 30, performs compression processing or decompression processing, and stores the processed data in the memory 30. Write to.

Reference numeral 40 denotes exposure control means for controlling the shutter 12 having a diaphragm function, and has a flash light control function in cooperation with the flash 48.
Reference numeral 42 denotes a distance measuring control means for controlling the focusing of the photographing lens 10, reference numeral 44 denotes a zoom control means for controlling zooming of the photographing lens 10, and reference numeral 46 denotes a barrier control means for controlling the operation of the protection means 102 as a barrier.

A flash 48 has an AF auxiliary light projecting function and a flash light control function.
The exposure control means 40 and the distance measurement control means 42 are controlled using the TTL method, and based on the calculation result obtained by calculating the captured image data by the image processing circuit 20, the system control circuit 50 performs the exposure control means 40 and the distance measurement. Control is performed on the control means 42.

A system control circuit 50 controls the entire digital camera 100, and a memory 52 stores constants, variables, programs, and the like for operation of the system control circuit 50.
Reference numeral 54 denotes a display unit such as a liquid crystal display device or a speaker that displays an operation state or a message using characters, images, sounds, or the like in accordance with execution of a program in the system control circuit 50, and an operation unit of the digital camera 100 One or a plurality of locations are installed in the vicinity where they can be easily seen, and are configured by a combination of, for example, an LCD, an LED, and a sounding element.

  The display unit 54 has a part of its function installed in the optical viewfinder 104. Among the display contents of the display unit 54, what is displayed on the LCD or the like includes single shot / continuous shooting display, self-timer display, compression rate display, number of recorded pixels, number of recorded pixels, number of remaining images that can be captured, shutter Speed display, Aperture display, Exposure compensation display, Flash display, Red-eye reduction display, Macro shooting display, Buzzer setting display, Clock battery level display, Battery level display, Error display, Multi-digit number information display, External There are a display state of the recording medium 200, a communication I / F operation display, a date / time display, and the like.

  Among the display contents of the display unit 54, what is displayed in the optical viewfinder 104 includes in-focus display, camera shake warning display, flash charge display, shutter speed display, aperture value display, exposure correction display, and the like.

Reference numeral 56 denotes an electrically erasable / recordable nonvolatile memory, such as an EEPROM.
58 is a timer control circuit for measuring time by receiving a timer measurement instruction from the system control circuit 50.

  Reference numerals 60, 62, 64, 66, 68 and 70 are operation means for inputting various operation instructions of the system control circuit 50, and may be a single unit such as a switch, a dial, a touch panel, pointing by line-of-sight detection, a voice recognition device, or the like. Consists of multiple combinations.

Here, a specific description of these operating means will be given.
Reference numeral 60 denotes a mode dial switch, which can switch and set various function modes such as power-off, automatic shooting mode, shooting mode, panoramic shooting mode, playback mode, multi-screen playback / erase mode, and PC connection mode.

  Reference numeral 62 denotes a shutter switch SW1, which is turned ON during the operation of a shutter button (not shown), and performs AF (auto focus) processing, AE (auto exposure) processing, AWB (auto white balance) processing, EF (flash pre-flash) processing, and the like. Instruct to start operation.

  Reference numeral 64 denotes a shutter switch SW2, which is turned on when an operation of a shutter button (not shown) is completed, and an exposure process for writing a signal read from the image sensor 14 to the memory 30 via the A / D converter 16 and the memory control circuit 22. A series of recording processes such as a development process using an operation in the image processing circuit 20 and the memory control circuit 22, a recording process in which the image data is read out from the memory 30, compressed in the compression / decompression circuit 32, and the image data is written in the recording medium 200. Instructs the start of processing operation.

  Reference numeral 66 denotes an image display ON / OFF switch, which can set ON / OFF of the image display unit 28. With this function, when photographing using the optical viewfinder 104, it is possible to save power by cutting off the current supply to the image display unit including a TFT LCD or the like.

  Reference numeral 68 denotes a quick review ON / OFF switch, which sets a quick review function for automatically reproducing image data taken immediately after photographing. In the present embodiment, in particular, a function for setting a quick review function when the image display unit 28 is turned off is provided.

  70 is an operation unit composed of various buttons, a touch panel, etc., a menu button, a set button, a macro button, a multi-screen playback page break button, a flash setting button, a single shooting / continuous shooting / self-timer switching button, menu movement + (plus) Button, menu shift- (minus) button, playback image shift + (plus) button, playback image shift- (minus) button, shooting image quality selection button, exposure correction button, date / time setting button, format operation button, and the like.

  80 is a power control means, which is composed of a battery detection circuit, a DC-DC converter, a switch circuit for switching a block to be energized, etc., and detects the presence / absence of a battery, the type of battery, the remaining battery level, and the detection result In addition, the DC-DC converter is controlled based on an instruction from the system control circuit 50, and a necessary voltage is supplied to each part including the recording medium for a necessary period.

Reference numeral 82 denotes a connector, 84 denotes a connector, and 86 denotes a power source means including a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery, a NiMH battery, or a Li battery, or an AC adapter.
90 is a card controller for transmitting and receiving data to and from an external recording medium such as a memory card, 91 is an interface with an external recording medium such as a memory card, 92 is a connector for connecting to an external recording medium such as a memory card, and 98 is a connector 92. The recording medium attachment / detachment detecting means detects whether or not the external recording medium 200 is attached to the recording medium.

  In the present embodiment, a single or a plurality of interfaces and connectors for attaching a recording medium may be provided. Moreover, it is good also as a structure provided with combining the interface and connector of a different standard. The interface and the connector may be configured using a PCMCIA card, a CF (Compact Flash (registered trademark)) card, or the like that conforms to a standard.

  Further, when the interface 91 and the connector 92 are configured using a PCMCIA card or a CF (Compact Flash (registered trademark)) card or the like, LAN card, modem card, USB card, IEEE1394 card, P1284 card By connecting various communication cards such as SCSI cards, communication cards such as PHS, etc., image data and management information attached to the image data can be transferred to and from other computers and peripheral devices such as printers. it can.

  Reference numeral 102 denotes protection means that is a barrier that prevents the imaging unit from being soiled or damaged by covering the imaging unit including the lens 10 of the digital camera 100. Reference numeral 104 denotes an optical viewfinder, which can perform photographing using only the optical viewfinder without using the electronic viewfinder function of the image display unit 28.

  In the optical viewfinder 104, some functions of the display unit 54, for example, a focus display, a camera shake warning display, a flash charge display, a shutter speed display, an aperture value display, an exposure correction display, and the like are installed. Reference numeral 200 denotes an external recording medium such as a memory card. The overall system configuration of the digital camera 100 has been described above. In addition, 110 is a communication means for communicating with the outside, and 112 is a connector for connecting a communication antenna.

FIG. 2 is a diagram schematically showing a logical configuration of a file system constructed in the external recording medium 200 in the present embodiment.
As shown in FIG. 2, the storage area of the external recording medium 200 is divided into a file system management area 210 and a data area 220. The management area 210 includes a master boot record (MBR) 211, a boot sector 212, a fat (FAT: file allocation table) 213, and a root directory entry 214.

  In the master boot record 211, a partition table is described. The partition table is a table showing logical areas called partitions, such as the position of the boot sector 212 and the size of the data area 220.

  The boot sector 212 describes basic information for handling data in which the file system is placed in the data area 220, such as the cluster size and the size of the fat 213. A cluster is a logical minimum size for handling data in the data area 220.

  Finally, the fat 213 is a table indicating the position of the file in the data area 220 with the cluster as a reference. By analyzing the fat 213, which cluster forms the file in which order, and which cluster is unused (entry cleared with “0” in the table) ) Can be known.

  In general, when a normal (logical) format is executed for such an external recording medium 200, the operation of the file system includes the master boot record 211 and the boot sector 212 from the device information of the external recording medium 200. After reconfiguring and writing, the area of the fat 213 and the root directory entry are cleared to “0” to make the external recording medium 200 apparently unused.

  In the present embodiment, such a format is referred to as a logical format. In this logical format, as described above, only the management area 210 of the file system is rewritten, and the data written in the data area 220 is written as it is without being rewritten.

  On the other hand, there is a format called a physical format. The physical format is a format that not only rewrites the management area 210 of the file system but also clears the value for the data area 220.

  In this embodiment, since the external storage medium 200 uses a flash memory, in the physical format in this embodiment, instead of clearing the value of the data area 220, the data in the data area 220 is erased. To do.

  In the digital camera 100 of the present embodiment, the format of the external recording medium 200 can be executed, and when a format is selected, a format menu is displayed as shown in FIG.

FIG. 4 is a flowchart showing processing when the format menu of FIG. 3 is selected.
Hereinafter, the process shown in FIG. 4 will be described in detail.
When the format menu is displayed as shown in FIG. 3, the user can select “format” or “cancel” in step S401. Here, when “Cancel” is selected, nothing is executed on the external recording medium 200 and the format menu is terminated.

On the other hand, when “format” is selected (OK) in step S401, the process proceeds to step S402 to secure a predetermined area A.
Next, the process proceeds to step S403, and the physical format of the predetermined area A secured in step S402 is performed.

  In step S404, data is written in a predetermined area A. At the time of this data writing, the first speed measurement (X) is performed using the timer control circuit 58. In step S405, the data is overwritten in the area where the previous data has been written. When the data is overwritten, the second speed measurement (Y) is performed using the timer control circuit 58.

  In step S406, it is determined whether the first writing speed X performed using the physical format is sufficiently faster than the second writing speed Y at the time of overwriting performed in the logical format.

  As a result of this determination, if it is sufficiently fast, the process proceeds to step S408, where the physical formatting of the entire medium is performed. As a result of the determination in step S406, if not, the process proceeds to step S407 to perform logical formatting. FIG. 5 shows an example of a screen displayed at the time of formatting.

  As described above, according to the present embodiment, the optimum format is automatically determined when the external recording medium is initialized, and the initialization is performed using the determined format. It is possible to prevent as much as possible that the data to be erased and the data to be erased exist on the same block and cannot be erased themselves or that other data is erased by mistake.

  Further, even when high speed is required, such as a flash memory attached to the digital camera 100, the time required to record data can be shortened. Thereby, for example, it is possible to sufficiently cope with a case where high-speed continuous shooting is executed using the digital camera 100 or a high-definition moving image is written at high speed.

(Another embodiment according to the present invention)
Each means constituting the data processing apparatus and each step of the data processing method in the embodiment of the present invention described above can be realized by operating a program stored in a RAM or ROM of a computer. This program and a computer-readable storage medium storing the program are included in the present invention.

  Further, the present invention can be implemented as, for example, a system, apparatus, method, program, or recording medium, and may be applied to a system composed of a plurality of devices. Moreover, you may apply to the apparatus which consists of one apparatus.

  In the present invention, a software program (in the embodiment, a program corresponding to the flowchart shown in FIG. 4) for realizing the functions of the above-described embodiment is directly or remotely supplied to a system or apparatus, This includes the case where the system or apparatus computer also achieves by reading and executing the supplied program code.

  Accordingly, since the functions of the present invention are implemented by computer, the program code installed in the computer also implements the present invention. In other words, the present invention includes a computer program itself for realizing the functional processing of the present invention.

  In that case, as long as it has the function of a program, it may be in the form of an object code, a program executed by an interpreter, script data supplied to the OS, or the like.

  As a recording medium for supplying the program, for example, floppy (registered trademark) disk, hard disk, optical disk, magneto-optical disk, MO, CD-ROM, CD-R, CD-RW, magnetic tape, nonvolatile memory card ROM, DVD (DVD-ROM, DVD-R) and the like.

  As another program supply method, a client computer browser is used to connect to an Internet homepage, and the computer program itself of the present invention or a compressed file including an automatic installation function is downloaded from the homepage to a recording medium such as a hard disk. Can also be supplied.

  It can also be realized by dividing the program code constituting the program of the present invention into a plurality of files and downloading each file from a different homepage. That is, a WWW server that allows a plurality of users to download a program file for realizing the functional processing of the present invention on a computer is also included in the present invention.

  In addition, the program of the present invention is encrypted, stored in a storage medium such as a CD-ROM, distributed to users, and key information for decryption is downloaded from a homepage via the Internet to users who have cleared predetermined conditions. It is also possible to execute the encrypted program by using the key information and install the program on a computer.

  In addition to the functions of the above-described embodiments being realized by the computer executing the read program, the OS running on the computer based on the instructions of the program is used for the actual processing. The functions of the above-described embodiment can be realized by performing some or all of the processes.

  Furthermore, after the program read from the recording medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion board or The CPU or the like provided in the function expansion unit performs part or all of the actual processing, and the functions of the above-described embodiments are realized by the processing.

It is a block diagram which shows an example of the system configuration | structure of the digital camera in this Embodiment. It is a figure which shows the logical structure in the external recording medium in this Embodiment. It is a figure which shows the screen displayed at the time of the format menu in this Embodiment. It is a flowchart which shows the process by the format menu in this Embodiment. It is a figure which shows the screen displayed at the time of the format execution in this Embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Shooting lens 12 Shutter 14 Image pick-up element 16 A / D converter 18 Timing generation circuit 20 Image processing circuit 22 Memory control circuit 24 Image display memory 26 D / A converter 28 Image display part 30 Memory 32 Image compression / expansion circuit 40 Exposure Control means 42 Distance control means 44 Zoom control means 46 Barrier control means 48 Flash 50 System control circuit 52 Memory 54 Display unit 56 Non-volatile memory 58 Timer control circuit 60 Mode dial switch 62 Shutter switch 64 Shutter switch SW1 First shutter switch SW2 Second shutter switch 66 Image display ON / OFF switch 68 Quick review ON / OFF switch 70 Operation unit 80 Power control means 82 Connector 84 Connector 86 Power supply means 90 Card controller 91 Interface 9 Connector 98 recording medium attachment detection unit 100 digital camera 102 safeguards 104 optical finder 200 external recording medium

Claims (8)

A data processing apparatus for recording the data on a recording medium having a data recording area for recording data and a management area of a file system,
Logical formatting means for logically formatting the file management area;
Data erasing means for electrically erasing data recorded in a data recording area of the storage medium by a predetermined size;
A data processing apparatus comprising: physical formatting means for executing erasure of the logical format and a data recording area in accordance with an erasing state of the data erasing means.   2. The data according to claim 1, further comprising: a format discriminating unit that discriminates whether to perform formatting using the logical formatting unit or the physical formatting unit in accordance with an erasing state of the data erasing unit. Processing equipment. Erasing time measuring means for measuring the erasing time of the data erasing means,
The data processing apparatus according to claim 2, wherein the format determination unit determines an erasure state based on a measurement result by the erasure time measurement unit. A data processing method for recording the data on a recording medium having a data recording area for recording data and a management area of a file system,
A logical formatting step for logically formatting the file management area;
A data erasing step for electrically erasing data recorded in a data recording area of the storage medium by a predetermined size;
A data processing method comprising: a physical formatting step for executing both the logical format and erasing of the data recording area in accordance with an erasing state of the data erasing step.   5. The data according to claim 4, further comprising a format discrimination step for discriminating which of the logical formatting step and the physical formatting step is executed in accordance with an erasing state of the data erasing step. Processing method. An erasing time measuring step of measuring an erasing time of the data erasing step,
6. The data processing method according to claim 5, wherein the format determination step determines an erasure state based on a measurement result obtained by the erasure time measurement step. A program for causing a computer to execute a data processing method for recording the data on a recording medium having a data recording area for recording data and a file system management area,
A logical formatting step for logically formatting the file management area;
A data erasing step for electrically erasing data recorded in a data recording area of the storage medium by a predetermined size;
A computer program for causing a computer to execute a logical formatting and a physical formatting process for executing erasing of a data recording area in accordance with an erasing state of the data erasing process.   8. A computer-readable recording medium on which the computer program according to claim 7 is recorded.

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