JP2006295269A - Electronic camera - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electronic camera which writes in photographic image data at a high speed. <P>SOLUTION: A flash memory erasure task checks the memory card of a recording medium for a task under accessing (S12). If there is no task, the flash memory erasure task searches an unused data area (ineffective area) in the card, with reference to a management table in a memory (S13). If there is a task, access check is repeated (S12). If there is no task exist but there is an ineffective area (S14), the flush memory erasure task erases flash memory in the ineffective area (S15). If there is no ineffective area exist (S14), the control returns back to access check of the recording medium (S12). After erasing the flash memory in the ineffective area, erased sector address of the management table in the memory and the number of times of erasure are updated (S16), before the control returns back to access check (S12). <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electronic camera, and more particularly to an electronic camera having a recording medium with a flash memory.

  2. Description of the Related Art Conventionally, electronic cameras that record and reproduce still images and moving images captured by a solid-state imaging device such as a CCD or CMOS using a memory card having a semiconductor memory as a recording medium are already on the market. As the semiconductor memory, a flash memory can be used, and a memory card equipped with the flash memory includes a memory control device that internally controls erasing and writing of data when writing data.

  In a memory card using flash memory, if there is an empty area when data is written, unnecessary data on the memory card is left as it is, and new data is written in the empty area. On the other hand, when there is no free space when data is written, it is necessary to delete unnecessary data from the memory card and then write new data. That is, an unnecessary data storage area is managed as a potential free area, and existing recording data is deleted when necessary. Since the time required for deletion is added, the data writing speed in this case is slower than when there is an empty area.

  There is an electronic camera that uses these flash memory operations to erase the flash memory when the memory card is initialized (complete format) (see, for example, Non-Patent Document 1). Thereby, after initialization of the memory card, data can be written at high speed until there is no free space.

On the other hand, Patent Document 1 discloses a flash memory management method that can quickly detect free space saturation and improve the reliability of the flash memory. A memory card using a flash memory has a function called wear leveling and has a built-in memory control device that averages the number of rewrites to the flash memory.
JP 09-198884 A Sanyo Electric Co., Ltd. Digital Movie Camera DMX-C4 Xacti Instruction Manual p. 129

  When it is desired to write captured image data at a high speed as in a conventional electronic camera, if there is only means for initialization, it is necessary to erase all the data that has been captured so far, which is inconvenient. In addition, if shooting and deletion are repeated, the writing speed decreases at an accelerated rate before the memory card is full. Furthermore, since it is necessary to erase an area more than necessary, it takes time and lacks convenience.

  In addition, by erasing the flash memory, a table for managing the number of rewrites of the flash memory is also initialized. As a result, the number of rewrites is reset, and the life of the flash memory may be shortened.

  Therefore, an object of the present invention is to provide an electronic camera that can always write image data at high speed without a complete format of a memory card.

  In order to solve the above problems, an electronic camera according to the present invention is an electronic camera that records a photographed image on a memory card with a built-in flash memory, and a management table that stores the number of erasures for each area of the flash memory; An invalid area searching means for searching for an invalid area in the data area of the flash memory, an erasing means for erasing a specified area of the flash memory, and an erase for each area of the flash memory with reference to the management table Control means for averaging the number of times, the control means for causing the erasing means to erase the invalid area of the flash memory in a predetermined state.

  According to the present invention, photographed image data can be written to the flash memory at high speed. In addition, since the erase area and the erase count of the flash memory are recorded in the management table, the number of rewrites of the storage area of the flash memory can be averaged, and the service life of the flash memory can be extended. In addition, the flash memory erase area and erase count are recorded in the management table, and there is a connection between the operation of the electronic camera and the flash memory erase method. The convenience of the camera can be increased.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a schematic block diagram of an electronic camera that is an embodiment of the present invention. In FIG. 1, reference numeral 100 denotes an electronic camera body that images a subject. The electronic camera main body 100 is connected to the recording media 200 and 250 and the lens unit 300 via each interface.

  A light beam incident on the photographing lens 304 adopting the single-lens reflex system is formed on the image sensor 12 as an optical image via the diaphragm 306, the lens mount 302, the lens mount 82, the mirror 92, and the shutter 10. The image sensor 12 converts an optical image into an electrical signal, and the shutter 10 controls the exposure amount to the image sensor 12.

  The A / D converter 14 converts the analog signal output of the image sensor 12 into a digital signal. The timing generation device 4 is controlled by the memory control device 20 and the system control device 40, and supplies a clock signal and a control signal to the image sensor 12, the A / D converter 14, and the D / A converter 24. The memory control device 20 controls the A / D converter 14, the timing generation device 4, the image processing device 18, the image display memory 22, the D / A converter 24, the memory 28, and the image compression / decompression device 30.

  The image processing device 18 performs predetermined pixel interpolation processing and color conversion processing on the image data from the A / D converter 14 and the image data from the memory control device 20. At the time of imaging, the image processing device 18 executes auto white balance (AWB) image processing.

  The output image data of the A / D converter 14 is written into the image display memory 22 or the memory 28 via the image processing device 18 and the memory control device 20 or via the memory control device 20.

  The image display unit 26 includes a TFT LCD (liquid crystal display) or the like. The image data for display written in the image display memory 22 is read to the D / A converter 24 at a constant cycle, and the output signal of the D / A converter 24 is applied to the image display unit 26. By sequentially displaying captured images on the image display unit 26, the image display unit 26 functions as an electronic viewfinder. Further, the image display unit 26 can arbitrarily turn on / off the display according to an instruction from the system control device 40, and in the state where the display is turned off, the power consumption of the electronic camera body 100 can be significantly reduced.

  The memory 28 temporarily stores captured image data of still images or moving images. The memory 28 has a sufficient storage capacity to store a predetermined number of still images or a moving image for a predetermined time. As a result, even in the case of continuous shooting or panoramic shooting in which a plurality of still images are continuously shot, a large amount of image data can be written in the memory 28 at high speed. The memory 28 can also be used as a work area for the system control device 40.

  The image compression / decompression apparatus 30 compresses and decompresses image data by adaptive discrete cosine transform (ADCT) or the like. The image compression / decompression apparatus 30 compresses the uncompressed image data stored in the memory 28 and writes it to the memory 28, and decompresses the compressed image data stored in the memory 28 and writes it to the memory 28.

  The system control device 40 controls the shutter 10 by the shutter control device 32 in cooperation with the aperture control device 312 that controls the aperture 306 according to the photometric result.

  The distance measuring device 34 measures the distance to the subject. For example, a light beam incident on the photographing lens 304 enters the distance measuring device 34 via the stop 306, lens mounts 302 and 82, the mirror 92, and a distance measuring sub mirror (not shown). The in-focus state is measured from the light.

  The photometric device 36 measures the exposure amount. For example, a light beam incident on the photographing lens 304 is incident on the photometric device 36 by a single lens reflex system via the diaphragm 306, lens mounts 302 and 82, mirrors 92 and 94, and a photometric lens (not shown). 36 measures the exposure amount of the subject from the amount of incident light. The photometric device 36 controls the amount of light emitted from the flash 38. The flash 38 has an AF auxiliary light projecting function and a flash light control (EE) function.

  The system control device 40 controls the shutter control device 32, the aperture control device 312 and the distance measurement control device 314 in accordance with the measurement results of the distance measuring device 34 and the photometry device 36, and performs focus control (AF) and exposure control (AE). Then, dimming control (EE) of the flash 38 is executed. In addition, the image processing device 18 performs calculations for distance measurement control, exposure control, and light control from the captured image data, and the system control device 40 performs focus control (AF), exposure control (AE), and control according to the results. Dimming control (EE) of the flash 38 may be performed. Thereby, autofocus, automatic exposure, and light control by a so-called TTL (Lou the Lens) method can be realized. Further, the photometric results of the distance measuring device 34 and photometric device 36 and the calculation result of the image processing device 18 may be used in combination.

  The system control device 40 controls the entire electronic camera body 100. The memory 42 stores constants, variables, programs, and the like for operating the system control device 40.

  The liquid crystal display unit 44 includes a speaker, and outputs an operation state, a message, and the like using characters, images, sounds, and the like according to execution of a program by the system control device 40. That is, the liquid crystal display unit 44 is installed in a single or a plurality of positions in the vicinity of the operation unit of the electronic camera main body 100 so as to be easily visible, and is configured by a combination of, for example, an LCD and an LED (light emitting diode) and a sounding element. Further, the liquid crystal display unit 44 is partially installed in the optical viewfinder 80.

  The content displayed on the LCD or the like of the liquid crystal display unit 44 includes, for example, single shot / continuous shooting display, self-timer display, compression rate display, recording pixel number display, recording number display, remaining image number display, shutter speed display , Aperture value 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, recording medium 200 And 250, a lens unit 300 attachment / detachment display, a communication I / F operation display, a date / time display, and a display showing a connection state with an external computer.

  On the other hand, display contents of the optical viewfinder 80 include, for example, in-focus display, shooting preparation completion display, camera shake warning display, flash charge display, flash charge completion display, shutter speed display, aperture value display, exposure correction display, and recording medium writing. Operation display and the like.

  The display contents such as LED include, for example, in-focus display, shooting preparation completion display, camera shake warning display, camera shake warning display, flash charge display, flash charge completion display, recording medium writing operation display, macro shooting setting notification display, and secondary There is a battery charge status display.

  Among the display contents of the liquid crystal display unit 44, what is displayed on a lamp or the like includes, for example, a self-timer notification lamp. This self-timer notification lamp may be used in common with AF auxiliary light.

  The nonvolatile memory 46 is electrically erasable and recordable, and is composed of, for example, a flash memory.

  The operation means 48 to 58 are means for inputting various operation instructions of the system control device 40, and are composed of a combination of a switch, a dial, a touch panel, pointing by eye-gaze detection, a voice recognition device, and the like.

  The mode dial switch 48 includes an automatic shooting mode, a program shooting mode, a shutter speed priority shooting mode, an aperture priority shooting mode, a manual shooting mode, a depth of focus priority (depth) shooting mode, a portrait shooting mode, a landscape shooting mode, and a close-up shooting mode. Each function shooting mode such as a sports shooting mode, a night scene shooting mode, and a panoramic shooting mode can be switched and set.

  The first shutter switch 50 is a switch that is turned on during the operation of a release button (not shown) (half-pressed state), and instructs the system controller 40 to start operations such as AF processing, AE processing, AWB processing, and EF processing. Used to do.

  The second shutter switch 52 is a switch that is turned on when the operation of the release button is completed (fully pressed), and the image signal read from the image sensor 2 is transmitted via the A / D converter 14 and the memory control device 20. Exposure processing to be written in the memory 28, development processing using computations in the image processing device 18 and the memory control device 20, and image data is read from the memory 28, compressed by the image compression / decompression device 30, and stored in the recording medium 200 or 250. This is used to instruct the system control device 40 to start the operation of a series of processing called recording processing.

  The playback switch 54 is used to instruct the system control device 40 to start a playback operation for reading a captured image from the memory 28, the recording medium 200, or the recording medium 250 and displaying it on the image display unit 26 in the shooting mode state. Is done.

  The single-shot / continuous-shot switch 56 takes a single frame when the second shutter switch 52 is pressed and sets a standby state, and continuously shooting while the second shutter switch 52 is pressed. Used to set the continuous shooting mode to continue.

  The operation unit 58 includes various buttons and a touch panel. Specifically, the operation unit 58 includes 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, a menu movement + (plus) button, a menu. When performing shooting and playback such as move- (minus) button, playback image move + (plus) button, playback image- (minus) button, image quality selection button, exposure compensation button, date / time setting button, panorama mode, etc. And a selection / switching button for setting selection and switching of various functions, and a determination / execution button for setting determination and execution of various functions when performing shooting and reproduction in a panoramic mode or the like. By providing a rotary dial switch instead of the plus button and the minus button, it becomes possible to select numerical values and functions more easily.

  The touch panel of the operation unit 58 has an image display on / off switch for setting on / off of the image display unit 26, and a quick review on / off for setting a quick review function for automatically reproducing image data taken immediately after shooting. Switch, compression mode switch for selecting JPEG compression rate or non-compression mode (CCDRAW mode), playback switch for setting each function mode such as playback mode, multi-screen playback / erase mode, and PC connection mode, If the first shutter switch 50 is pressed, the autofocus operation is started. Once focused, the one-shot AF mode that keeps the focused state and the first shutter switch 50 are continuously pressed. AF mode setting for setting the servo AF mode to continue autofocus operation. There is a switch or the like.

  With the power switch 60, the electronic camera body 100 can be switched on and off. The power switch 60 can also switch the power on / off of various accessory devices such as the lens unit 300, the external strobe, and the recording media 200 and 250 connected to the electronic camera main body 100 together with the main body 100.

  The power supply control device 62 includes a battery detection device, a DC-DC converter, a switch device that switches a block to be energized, and the like, and detects the presence / absence of a battery, the type of battery, and the remaining battery level. In addition, the DC-DC converter is controlled based on an instruction from the system controller 40, and a necessary voltage is supplied to each unit including the recording media 200 and 250 for a necessary period.

  Reference numeral 64 denotes a connector, 66 denotes a connector, and 68 denotes a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery NiMH battery or Li battery, or an AC power supply.

  70 and 74 are interfaces with the recording media 200 and 250 such as a memory card and a hard disk, 72 and 76 are connectors for connecting the recording media 200 and 250, and 78 is the connector 72 and 76 connected to the recording media 200 and 250. It is a recording medium attachment / detachment detection device that detects whether or not.

  In the present embodiment, the description is given assuming that there are two systems of interfaces and connectors for attaching the recording medium. Of course, the interface and the connector for attaching the recording medium may have a single or a plurality of systems. Moreover, it is good also as a structure provided with combining the interface and connector of a different standard. The interface and connector may be configured using, for example, a PCMCIA card (PC card), a CF (Compact Flash (registered trademark)) card, or the like.

  When the interfaces 70 and 74 and the connectors 72 and 76 are configured using a PCMCIA card or CF card conforming standard, a LAN card, modem card, USB card, IEEE 1394 card, P1284 card, SCSI card, PHS, etc. By connecting various communication cards such as communication cards, image data and management information attached to the image data can be transferred to and from other computers and peripheral devices such as printers.

  In the optical viewfinder 80, the light beam incident on the photographing lens 302 enters the optical viewfinder 80 through the diaphragm 306, the lens mounts 302 and 82, and the mirrors 92 and 94 by a single lens reflex system. It is possible to take an image using only the optical viewfinder 80 without using the electronic viewfinder function of the image display unit 26. Also, in the optical finder 80, display means for some functions of the liquid crystal display unit 44, for example, focus display, camera shake warning display, flash charge display, shutter speed display, aperture value display, exposure correction display, and the like. Is installed.

  The communication unit 84 has a communication function such as RS232C, USB, IEEE1394, P1284, SCSI, modem, LAN, or wireless communication.

  The connector 86 is means for connecting the electronic camera main body 100 to other devices by the communication unit 84, and is an antenna in the case of wireless communication.

  Reference numeral 88 denotes a connector serving as an interface for connecting the electronic camera body 100 to the lens unit 300 in the lens mount. The connector 90 has a function of supplying control signals, status signals, data signals, and the like between the electronic camera body 100 and the lens unit 300 and supplying currents of various voltages. The connector 90 may be configured to transmit a signal not only by electrical communication but also by light or voice.

  The mirrors 92 and 94 can guide the light incident on the photographing lens 304 to the optical viewfinder 80 by a single-lens reflex system. The mirror 92 may have either a quick return mirror configuration or a half mirror configuration.

  The recording medium 200 includes a recording unit 202 composed of a semiconductor memory, a magnetic disk, or the like, an interface 204 with the electronic camera body 100, and a connector 206 connected to the connector 72 of the electronic camera body 100. The recording medium 250 includes a recording unit 252 configured by a semiconductor memory, a magnetic disk, or the like, an interface 254 with the electronic camera body 100, and a connector 256 connected to the connector 76 of the electronic camera body 100.

  The interchangeable lens type lens unit 300 includes a lens mount 302 that mechanically couples the lens unit 300 to the electronic camera body 100. The lens mount 302 includes various functions for electrically connecting the lens unit 300 to the electronic camera body 100. Reference numeral 304 denotes a photographing lens, and 306 denotes an aperture. Reference numeral 308 denotes an interface for connecting the lens unit 300 to the electronic camera body 100 in the lens mount 302, and 310 denotes a connector that is electrically connected to the connector 90 of the electronic camera body 100. The connector 310 communicates control signals, status signals, data signals, and the like between the electronic camera main body 100 and the lens unit 300, and also has a function of supplying or supplying currents of various voltages. In place of electrical communication by the connector 310, a sign may be transmitted by light or voice.

  The aperture control device 312 controls the aperture 306 in cooperation with the shutter control device 32 that controls the shutter 10 based on the photometry information of the photometry device 36. The distance measurement control device 314 controls focusing of the photographing lens 304. A zoom control device 316 controls zooming of the taking lens 304. The lens control device 318 controls the entire lens unit 300. The lens control device 318 includes a memory for storing operation constants, variables, programs, and the like, and identification information such as a number unique to the lens unit 300, management information, open aperture value, minimum aperture value, focal length, and other functions. A non-volatile memory is provided for holding information and current and past setting values.

  FIG. 2 shows an internal configuration diagram of a memory card used as the recording media 200 and 250.

  In FIG. 2, 2a is an MBR (Master Boot Record), a partition table in which the location, size, and contents of the partition included in the memory card are written, and a master boot code that reads the boot code from the partition that is set to be active Is stored.

  Reference numeral 2b denotes a BPB (BIOS Parameter Block) in which the FAT size, the number of bytes in one sector, the number of sectors in a cluster, and various parameters of the memory card are recorded. Reference numeral 2c denotes a FAT (File Allocation Table), which manages in what order a file is recorded in which order on the memory card in units of clusters.

  Reference numeral 2d denotes a root directory in which information on file management on the memory card is recorded. Includes file size, creation date and time, first cluster number of file, etc. This is the top directory of the hierarchical directory.

  Reference numerals 2e, 2f, 2g, and 2h denote data areas in which actual file data and subdirectories are stored. Data has already been recorded in the areas 2e and 2g.

  The area 2h is an invalid area on the file system, that is, an area where dust remains after data is deleted. The area 2f is an area where the existing data is written on the file system, that is, an erase area.

  FIG. 3 is a diagram showing a memory card management table in the present embodiment. The management table indicates that when a memory card functioning as the recording medium 200 or 250 is inserted into the electronic camera body 100, when the electronic camera body 100 is turned on, and when the electronic camera body 100 is turned on. It shall be created and updated from time to time. As the contents of the management table, the address (Address) of the data area, the state (Status) of the sector of the address, and the number of erasures (Erase Count) are recorded. The electronic camera body 100 creates a management table on the memory 28 at the time of activation, and writes data in an erasing area where high-speed writing is possible with reference to the management table at the time of data writing. Further, the number of erases is controlled to be uniform so that the number of erases of all sectors is used on average.

  The operation of the embodiment shown in FIG. 1 will be described with reference to the flowchart shown in FIG. FIG. 4 is a flowchart of an invalid area erasing program that is activated when the electronic camera body 100 is powered on and continues to operate thereafter, that is, a flash memory erasing task.

  When power is supplied from the electronic camera body 100 to the memory card (S11), the flash memory erasure task checks whether there is a task accessing the memory card (S12). If power is not supplied from the electronic camera main body 100 to the recording units 202 and 252, S11 is repeated.

  When there is no task for accessing the memory card, the flash memory erasing task searches the management table of the memory 28 to find out whether there is a data area (invalid area) that is not used in the flash memory of the memory card. (S13). If there is a task for accessing the memory card, the access check is repeated (S12).

  If there is no task to access the recording medium 200 and there is an invalid area (S14), the flash memory erase task erases the invalid area (S15). When the flash memory in the invalid area is erased (S15), the erased sector address and erase count of the management table in the memory 28 are updated (S16), and the process returns to step S12. Even when there is no invalid area (S14), the process returns to step S12.

  Note that when the user selects the complete card initialization format by using the operation unit 58 and the liquid crystal display unit 44 of the electronic camera main body 100, the operations after step S13 in FIG. 3 may be performed. Of course, it is also possible to combine the operation shown in FIG. 4 by selecting the complete format of card initialization by the user himself / herself.

  FIG. 5 is a flowchart showing an invalid area erasing operation when the electronic camera of this embodiment is activated.

  When the power switch 60 of the electronic camera body 100 is turned on (S21), if a memory card is detected (S22), an invalid area is searched with reference to the management table in the memory 28 (S23). If no memory card is detected (S22), the process waits until a memory card is detected (S22). If there is an invalid area (S24), the flash memory erase task erases the invalid area (S25), updates the erased sector address and the erase count in the management table of the memory 28 (S26), and ends. To do. The process is also terminated when there is no invalid area (S24).

  FIG. 6 is a flowchart showing the erasing operation of the invalid area before the release button is fully pressed.

  When the first shutter switch 50 of the electronic camera body 100 is turned on in the shooting mode, the predicted shooting data size is determined (S31). If the predicted shooting data size is smaller than the erase area in the memory card (S32), the process moves to shooting (S36). When the predicted photographing data size is equal to or larger than the erased area (S32), the invalid area is searched with reference to the management table of the memory 28 (S33).

  If the predicted captured data size is larger than the free space (erase area + invalid area) in the memory card (S34), a warning “card capacity FULL” is issued to the liquid crystal display unit 44 (S39), and the process ends.

  If the predicted shooting data size is less than the free space (S34), the invalid area is deleted (S35). When the second shutter switch 52 is pressed (S36), the photographing data is written into the recording unit 202 or 252 of the recording medium 200 or 250 through the lens unit 300 and the image sensor 12 (S37). Then, the management table in the memory 28 is erased, the used sector address and the erase count are updated (S38), and the process is terminated.

  FIG. 7 is a flowchart showing the erasing operation of the invalid area after the release button is fully pressed.

  In the shooting mode, when the first shutter switch 50 of the electronic camera body 100 is turned on, the predicted shooting data size is determined (S41). If the predicted shooting data size is smaller than the erased area in the memory card (S42), the process moves to shooting (S45). When the predicted shooting data size is equal to or larger than the erased area (S42), the invalid area is searched with reference to the management table of the memory 28 (S43).

  If the predicted shooting data size is larger than the free space (erase area + invalid area) in the memory card (S44), a warning “card capacity FULL” is issued to the liquid crystal display unit 44 (S49), and the process ends.

  When the predicted shooting data size is less than the free space (S44), the second shutter switch 52 is turned on (S45), the invalid area is deleted (S46), and the shooting data is stored in the memory card through the lens unit 300 and the image sensor 12. Writing to the flash memory (S47). Then, the management table in the memory 28 is erased, the used sector address and the erase count are updated (S48), and the process is terminated.

  FIG. 8 is a flowchart showing the erasing operation of the invalid area after the photographic image data is written.

  When the first shutter switch 50 of the electronic camera body 100 is turned on in the shooting mode, the predicted shooting data size is determined (S51). If the predicted shooting data size is larger than the free space (erase area + invalid area) in the memory card (S52), a warning “card capacity FULL” is given to the liquid crystal display unit 44 (S58), and the process ends.

  When the predicted shooting data size is equal to or less than the free space (S52), the shooting data is written to the flash memory in the memory card through the lens unit 300 and the image pickup device 12 by turning on the second shutter switch (S53) (S54). After the photographing data has been written, the invalid area is searched by referring to the management table in the memory 28 (S55). After the search, the invalid area is deleted by the amount of data necessary for the next shooting calculated from the maximum image size and the low-compressed file (S56). Then, the management table in the memory 28 is erased, the used sector address and the erase count are updated (S57), and the process is terminated.

  Note that the above-described methods may be combined so that the user can select the timing of erasing the invalid area. The user may be able to browse the erase size of the invalid area.

  As described above, in this embodiment, the invalid area of the storage medium connected to the electronic camera is erased at a necessary time, so that the captured image can be stored on the recording medium at high speed as a whole.

It is a schematic block diagram of one Example of this invention. It is a figure which shows the structure in the memory card of a present Example. It is a block diagram of the flash memory management table which manages writing of the memory card of a present Example. It is a follow chart which shows the erase | elimination operation | movement of the invalid area | region which starts when the electronic camera of a present Example is turned on, and continues operating | moving after that. It is a flowchart of the operation | movement which erases an invalid area | region at the time of the electronic camera start of a present Example. It is a flowchart which shows the erase operation | movement of the invalid area | region before the release button full press of a present Example. It is a flowchart which shows the deletion operation | movement of the invalid area | region after the release button full depression of a present Example. It is a flowchart which shows the deletion operation | movement of the invalid area | region after the picked-up image writing of a present Example.

Explanation of symbols

10: Shutter 12: Image sensor 14: A / D converter 16: Timing generator 18: Image processing device 20: Memory control device 22: Image display memory 24: D / A converter 26: Image display units 28, 42: Memory 30: Image compression / decompression device 32: Shutter control device 34: Distance measurement device 36: Photometry device 38: Flash 40: System control device 44: Liquid crystal display unit 46: Non-volatile memory 48: Mode dial switch 50: Shutter switch (SW1) )
52: Shutter switch (SW2)
54: Playback switch 56: Single shooting / continuous shooting switch 58: Operation unit 60: Power switch 62: Power control devices 64, 66, 72, 76, 90: Connector 68: Power supplies 70, 74, 88, 204, 254, 308 : Interface (I / F)
78: Recording medium attachment / detachment detection device 80: Optical viewfinder 82, 302: Lens mount 84: Communication unit 86: Connector (or antenna)
92, 94: Mirror 100: Electronic camera body 200, 250: Recording medium 202, 252: Recording unit 204, 254: Interface (I / F)
206, 256: Connector 300: Lens unit 302, 310: Connector 304: Shooting lens 306: Aperture 312: Aperture control device 314: Distance measurement control device 316: Zoom control device 318: Lens control device

Claims (5)

An electronic camera that records captured images on a memory card with built-in flash memory,
A management table that stores the number of erasures for each area of the flash memory;
An invalid area searching means for searching for an invalid area in the data area of the flash memory;
Erasing means for erasing a specified area of the flash memory;
Control means for referring to the management table and averaging the number of erases for each area of the flash memory, and having control means for causing the erase means to erase the invalid area of the flash memory in a predetermined state An electronic camera characterized by that.   2. The control unit according to claim 1, wherein when the power is on and the memory card is not accessed, the control unit instructs the erasing unit to erase the invalid area of the flash memory. Electronic camera.   3. The electronic camera according to claim 1, wherein the control unit instructs the erasing unit to erase the invalid area of the flash memory in response to power-on.   The control means includes first comparison means for comparing the data size necessary for writing the captured image data with the size of the free area of the flash memory according to a half-press of the release button, and the data size is the free space 4. The electronic camera according to claim 1, wherein when the size of the area is larger, the erasing unit is instructed to erase the invalid area of the flash memory. 5.   The control means includes a first comparison means for comparing a data size required for writing the captured image data with a size of an empty area of the flash memory according to a half-press of a release button, and the data size of the empty area. A second comparing means for comparing the data size with the free space of the flash memory and the total size of the invalid area when the data size is larger than the size; The electronic camera according to any one of claims 1 to 3, wherein the erasing unit is instructed to erase the invalid area of the flash memory.

Images