JP4298088B2 - Imaging apparatus and control method thereof - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an imaging apparatus and a control method thereof, and more specifically to an electronic imaging apparatus and a control method thereof.
[0002]
[Prior art]
Electronic cameras that electronically record and play back still images and / or moving images using magnetic tape, memory cards having solid-state memory elements, hard disk drives, and the like as recording media have been widely commercialized. In these electronic cameras, an optical image by the photographing lens is converted into an electric image signal by a photoelectric conversion element. The image signal is recorded on a non-volatile recording medium after predetermined camera signal processing and recording processing. Generally, a volatile buffer memory is inserted in the middle.
[0003]
Recently, there has been a tendency to increase the capacity of the buffer memory, whereby a short photographing interval can be realized even with a high-quality image and / or a relatively low-speed recording medium.
[0004]
A format (DCF format) in which main image data and reduced image data (thumbnail images) are accommodated together in one data file has been proposed, whereby photographed image data can be handled regardless of the manufacturer of the electronic camera. FIG. 10 shows a schematic configuration diagram of the DCF format.
[0005]
[Problems to be solved by the invention]
The buffer memory in the conventional electronic camera is convenient to have a ring buffer configuration because the size of the image data changes depending on the number of pixels, the data compression rate, and the like.
[0006]
When creating thumbnail image data after main image data, thumbnail image data is arranged in the buffer memory following the main image data. However, in the DCF format, as shown in FIG. 10, since the thumbnail image data is arranged before the main image data, the data arrangement is reversed between the buffer memory and the recording medium. As a result, the thumbnail image data is first read from the buffer memory, and then the main image data located before the thumbnail image data is read. In this operation, for example, when the free space of the buffer memory is reduced, the corresponding main image data may be overwritten with the next photographed image data during the transfer of the thumbnail image data.
[0007]
A method of arranging the thumbnail image data before the main image data on the buffer memory is also conceivable. However, in general, the amount of data after compression cannot be determined unless image data is compressed. Therefore, it is necessary to secure a large free area for the thumbnail image. This wastes the buffer and leads to preparing a buffer memory having a larger capacity than necessary.
[0008]
An object of the present invention is to provide an imaging apparatus and a control method therefor that eliminate such inconvenience.
[0009]
[Means for Solving the Problems]
An imaging apparatus according to the present invention includes an imaging unit that converts an optical image into an electrical signal, a buffer memory that temporarily stores captured image information obtained by the imaging unit, and a recording header that includes a reduced image of the captured image information. Header generation means for generating and storing the captured image information in the buffer memory, memory control means for controlling access to the buffer memory, the recording header read from the buffer memory, and the imaging An image pickup apparatus including a recording medium for recording image information as one file, wherein the memory control unit first reads out a recording header from the buffer memory, and then captures captured image information corresponding to the recording header. Control is performed so that the read information is sequentially recorded on the recording medium, and the recording header is assigned. When recording on the recording medium, the area for storing the recording header of the buffer memory is not released, and when the captured image information is recorded on the recording medium, according to the recording of the captured image information. To store the captured image information storage area of the buffer memory. Open Then, after all of the read photographed image information is recorded on the recording medium, the storage area of the recording header corresponding to the photographed image information is stored. Open It is characterized by doing.
[0010]
An imaging apparatus control method according to the present invention includes a photoelectric conversion step for converting an optical image into an electrical signal, a storage step for temporarily storing captured image information obtained by the photoelectric conversion step in a buffer memory, and reduction of the captured image information. A header generation step for generating a recording header including an image and storing the captured image information in the buffer memory following the captured image information; first, the recording header is read from the buffer memory; and then, the captured image corresponding to the recording header An imaging apparatus control method comprising: a reading step for reading information; and a recording step for recording the recording header read from the buffer memory and the captured image information as a file on a recording medium, wherein the recording header is When recording on the recording medium, the recording head of the buffer memory is recorded. That there will be no opening of the area for storing, the photographed image information when recording on the recording medium, in accordance with the recording of the captured image information, the storage area of the photographed image information of the buffer memory Open And after recording all of the read photographed image information on the recording medium, the storage area of the recording header corresponding to the photographed image information is stored. Open It is characterized by doing.
[0011]
【Example】
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0012]
FIG. 1 shows a schematic block diagram of an embodiment of the present invention.
[0013]
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 transmitted through the photographing lens 10 and the shutter 12 into an electric signal, and 16 denotes a barrier or lid that protects the surface of the photographing lens 10. . Reference numeral 18 denotes a flash having an AF (autofocus) auxiliary light projecting function and a flash light control function. Reference numeral 20 denotes an exposure control circuit for controlling the shutter 14 and also has a flash light control function in cooperation with the flash 18. Reference numeral 22 denotes a distance measurement control circuit that controls the degree of focus of the photographic lens 10, reference numeral 26 denotes a zoom control circuit that controls the magnification of the photographic lens 10, and reference numeral 26 denotes a barrier control circuit that controls opening and closing of the barrier 16. Reference numeral 28 denotes a system control circuit that controls the whole including the control circuits 20, 22, 24, and 26.
[0014]
30 is an A / D converter that converts the analog signal output of the image sensor 14 into a digital signal, 32 is an image display memory that stores an output image of the image sensor 14 for image display, and 34 is a captured still image and moving image. Is temporarily stored, and image data read from the recording medium is temporarily stored. The memory 34 has a storage capacity sufficient to store a predetermined number of still images or a moving image for a predetermined time. The memory 34 can execute high-speed continuous shooting and panoramic shooting for continuously shooting a plurality of still images. As shown in FIG. 11, the write buffer is set in the memory 34. The memory 34 is also used as a work area for the system control circuit 28.
[0015]
A compression / decompression circuit 36 compresses / decompresses image data by adaptive discrete cosine transform (ADCT). In the present embodiment, the compression / decompression circuit 36 compresses and decompresses the image data and the compressed image data stored in the memory 34 and rewrites them in the memory 34.
[0016]
A memory control circuit 38 controls writing and reading of the image display memory 32 and the memory 34 and controls the compression / decompression circuit 36. 40 performs TTL (through the lens) color balance adjustment, pixel interpolation processing, and color conversion processing on the image data output from the A / D converter 30 and the image data from the memory control circuit 38; This is an image processing circuit supplied to the memory control circuit 38. The output image data of the A / D converter 30 is written into the image display memory 32 and / or the memory 34 via the image processing circuit 40 and the memory control circuit or via the memory control circuit 38.
[0017]
A D / A converter 42 converts image data read from the image display memory 32 and output from the memory control circuit 38 into an analog signal, and 44 an analog image signal output from the D / A converter 42 as an image. An image display device for display. The image display device 44 functions as an electronic viewfinder by causing the image display device 44 to display the output image of the image sensor 14 in a centric manner. The system control circuit 28 can freely control (on / off) the display (power-on) of the image display device 44. By turning off the image display device 44, power consumption can be reduced.
[0018]
A timing generation circuit 46 supplies a clock signal and a control signal to the image sensor 14, the A / D converter 30, and the D / A converter 42 under the control of the memory control circuit 38 and the system control circuit 28.
[0019]
The system control circuit 28 controls the exposure control circuit 20, the distance measurement control circuit 22 and the flash 18 according to the calculation result of the image processing circuit 40, TTL (through the lens) AF (autofocus) processing, AE (Automatic exposure) processing and EF (flash pre-emission) processing are performed.
[0020]
Reference numeral 48 denotes a memory that stores constants, variables, programs, and the like for operation of the system control circuit 28. Reference numeral 50 denotes an image / sound output device including a liquid crystal display device that displays an operation state and a message as characters, images, sounds, and the like according to execution of a program in the system control circuit 28, a light emitting element, and a speaker that outputs sound. . The image / sound output device is installed in a single or a plurality of positions in the vicinity of the operation unit where it can be easily seen, and is configured by, for example, a combination of a liquid crystal display panel (LCD), a light emitting element (LED), and a sounding element.
[0021]
The image and audio output device 50 displays images as follows: single shot / continuous shooting, self-timer, compression rate, number of recorded pixels, number of recorded images, number of remaining images, shutter speed, aperture value, exposure compensation, flash, red-eye Relaxation, macro photography, buzzer setting, clock battery level, battery level, error, multi-digit number information, recording medium attachment / detachment status, communication I / F operation, date / time, and the like. The image display function of the image / sound output device 50 is installed in the optical viewfinder 52. What is displayed in the optical viewfinder 52 is the in-focus state, camera shake warning, flash charging, shutter speed, aperture value, exposure correction, and the like.
[0022]
Reference numeral 54 denotes a nonvolatile memory capable of electrically recording and erasing data, such as an EEPROM.
[0023]
A communication circuit 56 has various communication functions such as RS232C, USB, IEEE1394, P1284, SCSI, modem, LAN, and wireless communication, and is connected to an external device via a connector (or antenna) 58.
[0024]
Reference numeral 60 denotes a power supply control circuit including a battery detection circuit, a DC-DC converter, and a switch circuit for switching a block to be energized, and detects the presence / absence of a battery, the type of battery and the remaining battery level, and the detection result and system The DC-DC converter is controlled based on an instruction from the control circuit 28, and a necessary voltage is supplied to each unit for a necessary period. A power supply 66 is connected to the power supply control circuit 62 via connectors 62 and 64. The power source 66 includes a primary battery such as an alkaline battery and a lithium battery, a secondary battery such as a NiCd battery, a NiMH battery, and a Li battery, and an AC adapter.
[0025]
68 and 70 are removable recording media such as a memory card and a hard disk, 72 and 74 are connectors for connecting the recording media 68 and 70, and 76 and 78 are data between the recording media 68 and 70 and the memory 34. It is an interface to exchange. Reference numeral 80 denotes a recording medium attachment / detachment detector that detects whether the recording media 68 and 70 are connected to the connectors 72 and 74, respectively.
[0026]
Each of the recording media 68 and 70 includes a recording unit 82 made of a semiconductor memory and a magnetic disk, an interface 84, and a connector 86 connected to the connectors 72 and 74.
[0027]
In this embodiment, two systems of interfaces 76 and 78 for connecting the recording media 68 and 70 are provided. However, this is an example, and only one system or three or more systems may be used. A plurality of interfaces of the same standard may be provided, or interfaces of different standards may be provided. The interfaces 76 and 78 and the connectors 72 and 74 may be compliant with a standard such as a PCMCIA card or a CF card.
[0028]
When the interfaces 76 and 78 and the connectors 72 and 74 conform to a standard such as a PCMCIA card or a CF card, the connectors 72 and 74 include a LAN card, a modem card, a USB card, an IEEE 1394 card, a P1284 card, and a SCSI card. , And various communication cards such as communication cards such as PHS, through which image data and management information attached to the image data are transferred to and from other computers and peripheral devices such as printers. I can do it.
[0029]
As operation means for the system control circuit 28, there are the following means. Reference numeral 88 denotes a mode dial switch for switching and setting each function mode such as power-off and automatic shooting mode, shooting mode, panoramic shooting mode, playback mode, multi-screen playback / erase mode, and PC connection mode.
[0030]
90 is turned on during the operation of a shutter button (not shown), and instructs to start operations such as AF (autofocus) processing, AE (automatic exposure) processing, AWB (auto white balance) processing, and EF (flash preflash) processing. 1 shutter switch.
[0031]
A second shutter switch 92 is turned on when the operation of a shutter button (not shown) is completed, and instructs the start of the recording operation of the image signal output from the image sensor 14 to the recording medium 68 or 70.
[0032]
Reference numeral 94 denotes an image display switch for instructing on / off of display (or power) of the image display device 44. When photographing using the optical finder 52, power consumption can be reduced by shutting off the power supply to the image display device 44.
[0033]
Reference numeral 96 denotes a quick review switch for setting a quick review function for automatically reproducing photographed image data immediately after photographing. Particularly in the present embodiment, the quick review function can be set to be effective even when the image display device 44 is powered off.
[0034]
An operation device 98 includes various buttons and a touch panel. Specifically, the menu button, set button, macro button, multi-screen playback page break button, flash setting button, single / continuous / self-timer switching button, menu movement + (plus) button, menu movement-(minus) There are a button, a playback image move + (plus) button, a playback image- (minus) button, a shooting image quality selection button, an exposure correction button, a date / time setting button, and the like.
[0035]
Specifically, these members 88 to 98 are realized by appropriately combining a switch, a dial, a touch panel, a pointing by gaze detection, a voice recognition device, and the like.
[0036]
2, 3 and 4 show a flowchart of the main routine of this embodiment. The operation of this embodiment will be described with reference to FIGS.
[0037]
When the power is turned on by battery replacement or the like, the system control circuit 28 initializes various flags and control variables (S1), and initializes the image display of the image display device 44 to an off state (S2).
[0038]
The system control circuit 28 determines the setting position of the mode dial 88 (S3), and when the mode dial 88 is set to power off (S3), the display on each display unit is changed to the end state, and the barrier 16 is set. The camera 10 is closed to protect the photographing lens 10, necessary parameters including flags, control variables, etc., setting values and setting modes are recorded in the nonvolatile memory 54, and unnecessary power supply for each part including the image display device 44 is performed by the power supply control circuit 60. Is cut off (S5), and the process returns to S3.
[0039]
When the mode dial 88 is set to the photographing mode (S3), when there is data to be transferred to the recording medium in the write buffer, transfer of the data to the recording medium is started (S6). Details of the data transfer start process (S6) to the recording medium will be described later with reference to FIG.
[0040]
If the mode dial 88 has been set to another mode (S3), the system control circuit 28 executes processing corresponding to the selected mode (S4), and returns to S3 when the processing is completed. Detailed operation in the reproduction mode will be described later with reference to FIG.
[0041]
The system control circuit 28 determines whether there is a problem in the operation of the present embodiment in terms of the remaining capacity and the operation status of the power supply 66 via the power supply control circuit 60 (S7). The image / audio output device 50 issues a predetermined warning by image and / or sound (S9), and returns to S3.
[0042]
If there is no problem with the power supply 66 (S7), the system control circuit 28 determines whether there is a problem with the recording / reproducing operation of the recording medium 68 or 70 (S18). If a problem is found (S8), the image / sound output device 50 issues a predetermined warning by image and / or sound (S9), and returns to S3.
[0043]
When there is no problem in the operation state of the recording media 68 and 70 (S8), the image / audio output device 50 notifies the user of various setting states by image and / or sound (S10). When the image display of the image display device 44 is on, the image display device 44 displays various setting states.
[0044]
The system control circuit 28 checks the setting state of the quick review switch 96 (S11). If it is on (S11), it sets a quick review flag (S12). If it is off (S11), the quick review flag is set. Is canceled or cleared (S13). The quick review flag is stored in the internal memory or the memory 48 of the system control circuit 28.
[0045]
Subsequently, the system control circuit 28 checks the setting state of the image display switch 94 (S14), and when the image display is on (S14), sets the image display flag (S15) and displays the image on the image display device 44. Is turned on (S16), and a through display state in which captured image data is sequentially displayed is set (S7). In the through display state, the output image of the image sensor 14 is sequentially written into the image display memory 32 via the A / D converter 30, the image processing circuit 40, and the memory control circuit 38, and the stored image data in the image display memory 32 is It is read by the memory control circuit 38 and applied to the image display device 44 via the D / A converter 42. Thereby, the image display device 44 functions as an electronic viewfinder.
[0046]
When the image display switch 94 is set to image display off (S15), the system control circuit 28 cancels or clears the image display flag (S18), and sets the image display of the image display device 44 to an off state (S18). S119). When the image display is off, the electronic viewfinder function by the image display device 44 cannot be used, so that the optical viewfinder 52 is used for photographing. In this case, the power consumption of the image display device 44 and the D / A converter 42 that consume a large amount of power can be reduced.
[0047]
The image display flag is stored in the internal memory or the memory 48 of the system control circuit 28.
[0048]
S3 to S19 are repeated until the first shutter switch 90 is turned on (S20). When the first shutter switch 90 is turned on (S20), the system control circuit 28 interrupts data transfer from the write buffer of the memory 34 to the recording medium 68 or 70 (S121). If the image display flag is set (S22), the system control circuit 28 sets the image display device 44 to the freeze display state (S23). In the freeze display state, rewriting of image data in the image display memory 32 via the image sensor 14, the A / D converter 30, the image processing circuit 40, and the memory control circuit 38 is prohibited, and finally written in the image display memory 32. The obtained image data is supplied to the image display device 44 via the memory control circuit 38 and the D / A converter 42. As a result, the same image is displayed on the screen of the image display device 44. If the image display flag has been canceled (S22), freeze display is not selected.
[0049]
The system control circuit 28 focuses the photographing lens 10 on the subject by the distance measurement process, and determines the aperture value and the shutter time by the photometry process (S24). In the photometric process, use of the flash 18 is also set if necessary. Details of the distance measurement / photometry processing (S24) will be described later with reference to FIG.
[0050]
After the distance measurement / photometry processing (S24), the system control circuit 28 checks the image display flag (S26), and if the image display flag is set, sets the image display device 44 in the same through display state as in S17 ( S26).
[0051]
If the second shutter switch 92 is not turned on (S27) and the first shutter switch 90 is turned off (S28), the process returns to S3. When the second shutter switch 92 is turned on (S27), the system control circuit 28 checks the image display flag (S29), and if the image display flag is set, sets the image display device 44 to the fixed color display state. (S30). In the fixed color display state, instead of the image data output from the image sensor 14 and written to the image display memory 32 via the A / D converter 30, the image processing circuit 40, and the memory control circuit 38, the memory control circuit 38. Supplies fixed color image data to the D / A converter 42. As a result, a fixed color image is displayed on the screen of the image display device 44. Of course, if the image display flag is canceled or cleared (S29), the fixed color display is passed.
[0052]
The system control circuit 28 converts an image captured by the image sensor 14 via the A / D converter 30, the image processing circuit 40 and the memory control circuit 38, or via the A / D converter 30 and the memory control circuit 38. A shooting process including a memory transfer process to be written in the memory 34 and a developing process for performing various image processes on the shot image data in the memory 34 is executed using the memory control circuit 38 and the image processing circuit 40 as necessary (see FIG. S31). Details of the photographing process (S31) will be described later with reference to FIG.
[0053]
The system control circuit 28 checks the image display flag (S32), and when the image display flag is set (S32), performs a quick review display (S35). When the image display flag is set, since the image display device 44 is always used as an electronic viewfinder even during shooting, the quick review display immediately after shooting is naturally performed. When the image display flag is released (S32), the system control circuit 28 checks the quick review flag (S33), and when the quick review flag is set (S33), the image display device 44 is turned on. The state is set (S34), and a quick review display is performed (S135).
[0054]
When the image display flag and the quick review flag are both canceled or cleared (S32, S33), the image display device 44 remains in the display off state. In this case, nothing is displayed on the image display device 44 even after shooting, and no quick review display is performed. This is a usage method that places importance on power saving without using the electronic viewfinder function of the image display device 44, as in the case of continuing shooting using the optical viewfinder 52, without requiring confirmation of the shot image immediately after shooting. .
[0055]
The system control circuit 28 reads the captured image data written in the memory 34, performs various image processing using the memory control circuit 38 and, if necessary, the image processing circuit 40, and image compression processing according to the setting mode by the compression / decompression circuit 36. Are written in the write buffer of the memory 34 and finally transferred to the recording medium 68 or 70 (S36). Details of this recording processing, particularly writing processing to the write buffer, will be described later with reference to FIG.
[0056]
If the second shutter switch 92 remains on after the recording process (S36) (S27), the system control circuit 28 checks the continuous shooting flag (S38), and if the continuous shooting flag is set. (S38), the process returns to S31 to continuously execute the next shooting. When the continuous shooting flag is not set (S38), it waits for the second shutter switch 92 to be turned off (S37).
[0057]
When the second shutter switch 92 is turned off after the recording process (S36) (S37), it waits for the elapse of a predetermined minimum review time (S39). Thereby, the quick review display time by the image display device 44 can be set as the minimum review time, and the photographer can confirm the confirmation of the photographed image. In addition, the quick review display can be continued for an unnecessarily long time, thereby preventing the next shooting opportunity from being lost.
[0058]
Data transfer from the write buffer of the memory 34 to the recording media 68 and 70 may be performed by interrupt processing from the recording media 68 and 70 except for the first instruction. May be.
[0059]
In this example, in the recording process (S36), image data is written to the write buffer every time shooting is performed. However, in order to increase the continuous shooting speed, writing to the write buffer is executed immediately before S137, and continuous shooting is performed. A plurality of images taken in step 1 may be written together in the write buffer. Further, when the memory 34 has a sufficient storage capacity, the recording process (S36) itself is moved immediately before S39, and a plurality of images taken by continuous shooting are collectively compressed and written to the write buffer. Also good.
[0060]
When the image display flag is set (S40), the system control circuit 28 sets the image display device 44 to the through display state (S43). In this case, since the image display device 44 automatically enters the through display state after displaying the photographed image by the quick review display, the photographer can immediately prepare for the next photographing. If the image display flag has been canceled or cleared (S40), the system control circuit 28 sets the image display device 44 to the display off state. In this case, the power consumption can be greatly reduced since the image display device 44 is turned off after the captured image is confirmed by the quick review display.
[0061]
If the first shutter switch 90 remains on (S43), the system control circuit 28 returns to S27 to prepare for the next shooting, and if the first shutter switch 90 is off (S43), a series of operations are performed. After the photographing operation is finished, the process returns to S3.
[0062]
FIG. 5 shows a detailed flowchart of the distance measurement / photometry process (S24). The system control circuit 28 reads out the charge signal from the image sensor 14 and sequentially supplies it to the image processing circuit 40 via the A / D converter 30 (S51). The image processing circuit 40 uses TTL (through-the-lens) type AE (automatic exposure) processing, EF (flash pre-flash) processing, and AF (autofocus) processing using the sequentially supplied image data. A predetermined calculation is performed. The image processing circuit 40 extracts a specific portion as necessary from the total number of captured pixels and uses it for the calculation. As a result, different modes such as the center emphasis mode, the average mode, and the evaluation mode can be selected as appropriate in each of the TTL method AE, EF, AWB, and AF processes, and it is possible to perform optimal calculations for each mode.
[0063]
The system control circuit 28 refers to the calculation result of the image processing circuit 40 and controls the shutter speed and aperture of the shutter 12 by the exposure control circuit 40 until it is determined that the exposure is appropriate (S52) (53). The system control circuit 28 determines whether or not the flash 18 is necessary using the measurement data obtained by the AE control (S54), and if necessary, sets the flash flag to charge the flash 18 ( S55).
[0064]
When it is determined that the exposure is appropriate (S52), the system control circuit 28 stores the measurement data and / or setting parameters in the internal memory or the memory 48.
[0065]
Using the calculation results in the image processing circuit 40 and the measurement data obtained by the AE control, the system control circuit 28 adjusts the color processing parameters by the image processing circuit 40 until it is determined that the white balance is appropriate (S56). The white balance is adjusted (S57).
[0066]
When it is determined that the white balance is appropriate (S56), the system control circuit 28 stores measurement data and / or setting parameters in the internal memory or the memory 48.
[0067]
Using the measurement data obtained by the AE control and the AWB control, the system control circuit 28 determines that the photographing lens 10 is in the in-focus position (S58), and the focusing lens of the photographing lens by the distance measurement control circuit 22 is determined. Is controlled (S59).
[0068]
If it is determined that the photographing lens is in focus (S58), the system control circuit 28 stores the measurement data and / or setting parameters in the internal memory or the memory 48, and ends the distance measurement / photometry processing routine.
[0069]
FIG. 5 shows a detailed flowchart of the photographing process (S31). The system control circuit 28 adjusts the aperture value of the shutter 12 by the exposure control circuit 20 according to the photometric data stored in the internal memory of the system control circuit 28 or the memory 48, opens the shutter 12, and exposes the image sensor 14 (S61). , S62). If the flash flag is set (S63), the flash 18 is caused to emit light (S64).
[0070]
The system control circuit 28 waits for the exposure of the image sensor 14 to end (S65), and closes the shutter 12 (S66). A charge signal is read out from the image sensor 14 and photographed in the memory 34 via the A / D converter 30, the image processing circuit 40 and the memory control circuit 38, or via the A / D converter 30 and the memory control circuit 38. Image data is written (S67).
[0071]
When it is necessary to perform frame processing according to the set shooting mode (S68), the system control circuit 28 uses the memory control circuit 38 and, if necessary, the image processing circuit 40 to write to the memory 34. After the image data is read and the vertical addition process (S69) and the color process (S70) are sequentially performed, the processed image data is written in the memory 34.
[0072]
The system control circuit 28 reads the image data from the memory 34 and transfers the display image data to the image display memory 32 via the memory control circuit 38 (S71).
[0073]
FIG. 7 shows a detailed flowchart of the recording process (S36). The system control circuit 28 uses the memory control circuit 40 and, if necessary, the image processing circuit 38 to read out the captured image data in the memory 34 and perform pixel square processing for interpolating the vertical / horizontal pixel ratio to 1: 1 (S81). ) Write the processed image data to the memory 34.
[0074]
Then, the image data in the memory 34 is read out, the image compression processing corresponding to the set mode is performed by the compression / decompression circuit 36 (S82), and the image data (main image data) is transferred to the write buffer area provided in the memory 34. (S83). Thereafter, a thumbnail image smaller than the main image is created by the compression / decompression circuit 36 (S84), header data including thumbnail image information is created (S85), and transferred to the write buffer area of the memory 34 (S85). S86). A write buffer area is secured for the transferred data, and whether the secured area is the main image or header & thumbnail data is stored in the work area of the memory 48 (SS87). This completes the recording process (S36).
[0075]
FIG. 7 shows a detailed flowchart of the data transfer instruction process (S6). The system control circuit 28 checks whether or not untransferred data exists in the write buffer of the memory 34 (S91). If there is untransferred data in the write buffer as shown in FIG. It is determined whether it is in progress (S92), and if data transfer is not in progress, data transfer is started (S93).
[0076]
FIG. 9 shows a detailed flowchart of the transfer process from the write buffer to the recording media 68 and 70. This process is activated by an interrupt request from the recording media 68 and 70.
[0077]
The system control circuit 28 transfers untransferred data in the write buffer of the memory 34 to the recording medium 68 or 70 (S101), and determines whether the transferred data is main image data in the DCF format from the stored information of the memory 48. Judgment is made (S102). If it is not the header & thumbnail information, it is determined whether or not the transfer of the main image data has been completed (S103). If the transfer of the main image has not been completed (S103), the reserved area is released by the amount of the data transfer. When the transfer of the main image is completed (S103), the area for securing the header and thumbnail data is also released (S105).
[0078]
That is, as shown in FIG. 13, the reserved area is not updated during the transfer of the header and thumbnail portion, and as shown in FIG. 14, the reserved area is released according to the transfer amount during the transfer of the main image. As shown in FIG. 15, when the transfer of the main image is completed, the reserved areas for the already transferred header / thumbnail are also released.
[0079]
With this processing, when the image data in the DCF format is realized by the ring buffer, it is possible to prevent the data from being corrupted even if the buffer capacity is not wasted and the buffer capacity is fully used.
[0080]
Data transfer to the recording media 68 and 70 is executed in step S93 every time divided by a certain unit even if it is started by the interrupt processing from the recording media 68 and 70 except for the first data transfer start (S93). May be.
[0081]
FIG. 16 shows an operation flowchart when the mode dial is set to the reproduction mode.
[0082]
The system control circuit 28 checks whether or not the immediately preceding mode is the shooting mode (S110), and when the immediately preceding mode is the shooting mode (S110), transfers the last captured image data to the work area of the memory 34 (S110). S111). When the immediately preceding mode is other than the shooting mode (S110), the image data in the recording media 68 and 70 is read into the work area of the memory 34 according to the key operation of the operation device 98 (S112).
[0083]
The system control circuit 28 decodes the image data existing in the work area of the memory 34 by the compression / decompression circuit 36, transfers it to the image display memory 32, and displays the image on the screen of the image display device 44 (S113).
[0084]
With this process, when switching from the shooting mode to the playback mode without turning off the power, the latest captured image remaining in the write buffer is accessed at high speed without accessing the recording media 68 and 70 having a relatively low transfer speed. Can be displayed.
[0085]
Recording media 68 and 70 are not only memory cards such as PCMCIA cards and compact flash and hard disks, but also micro DAT, magneto-optical disks, optical disks such as CD-R and CD-WR, phase change optical disks such as DVD, etc. It may consist of. The recording media 68 and 70 may be composite media in which a memory card and a hard disk are integrated. Furthermore, a part of the composite medium may be detachable.
[0086]
Although the recording media 68 and 70 have been described as being removable, one or both of them may be fixedly connected to the apparatus of this embodiment. A configuration in which a plurality of recording media 68 and 70 can be connected may be employed.
[0087]
In the above embodiment, it has been described that the data on the write buffer of the memory 34 is transferred to the recording media 68 and 70 by the interruption from the recording media 68 and 70. However, the state of the recording media 68 and 70 is changed without using the interruption. It may be configured to periodically check and transfer data.
[0088]
【The invention's effect】
As can be easily understood from the above description, according to the present invention, the utilization efficiency of the buffer memory to the recording medium can be increased with a simple configuration, and the cost can be reduced.
[Brief description of the drawings]
FIG. 1 is a schematic block diagram of an embodiment of the present invention.
FIG. 2 is a part of a flowchart of a main routine of the present embodiment.
FIG. 3 is a part of a flowchart of a main routine of the present embodiment.
FIG. 4 is a part of a flowchart of a main routine of the present embodiment.
FIG. 5 is a flowchart of distance measurement / photometry processing (S24).
FIG. 6 is a flowchart of a photographing process (S31).
FIG. 7 is a flowchart of recording processing (S36).
FIG. 8 is a flowchart of data transfer start processing (S6).
FIG. 9 is a detailed flowchart of a transfer process from a write buffer to recording media 68 and 70;
FIG. 10 is an explanatory diagram of a DCF file structure.
FIG. 11 is an arrangement example of write buffers on the memory 34;
FIG. 12 is a schematic diagram of a reserved area in a write buffer immediately before data transfer.
FIG. 13 is a schematic diagram of a reserved area in a write buffer during transfer of header and thumbnail data.
FIG. 14 is a schematic diagram of a reserved area in a write buffer during main image data transfer.
FIG. 15 is a schematic diagram of a reserved area in a write buffer immediately after main image data transfer.
FIG. 16 is a flowchart of a playback mode according to the present embodiment.
[Explanation of symbols]
10: Photography lens
12: Shutter
14: Image sensor
16: Barrier or lid
18: Flash
20: Exposure control circuit
22: Ranging control circuit
26: Zoom control circuit
26: Barrier control circuit
28: System control circuit
30: A / D converter
32: Image display memory
34: Memory
36: Compression / decompression circuit
38: Memory control circuit
40: Image processing circuit
42: D / A converter
44: Image display device
46: Timing generation circuit
48: Memory
50: Image / audio output device
52: Optical viewfinder
54: Non-volatile memory
56: Communication circuit
58: Connector (or antenna)
60: Power supply control circuit
62, 64: Connector
66: Power supply
68, 70: Recording medium
72, 74: Connector
76, 78: Interface
80: Recording medium attachment / detachment detector
82: Recording section
84: Interface
86: Connector
88: Mode dial switch
90: First shutter switch
92: Second shutter switch
94: Image display switch
96: Quick review switch
98: Operating device

Claims (6)

Imaging means for converting an optical image into an electrical signal;
A buffer memory for temporarily storing captured image information obtained by the imaging means;
Header generating means for generating a recording header including a reduced image of the captured image information, and storing the header in the buffer memory following the captured image information;
Memory control means for controlling access to the buffer memory;
An image pickup apparatus comprising the recording header read from the buffer memory and a recording medium for recording the captured image information as one file, wherein the memory control unit includes:
First, the recording header is read from the buffer memory, then the captured image information corresponding to the recording header is read, and the read information is sequentially recorded on the recording medium.
When the recording header is recorded on the recording medium, the area for storing the recording header of the buffer memory is not released,
The photographed image information when recording on the recording medium, in accordance with the recording of the captured image information, and releases the storage area of the photographed image information of the buffer memory,
Imaging apparatus characterized by after recording all the recording medium the captured image information read, releases the storage area of the recording header corresponding to the photographic image information.   The imaging apparatus according to claim 1, wherein the buffer memory is a ring buffer. An image display means;
The imaging apparatus according to claim 1, further comprising a control unit that causes the image display unit to display the latest captured image information stored in the buffer memory in response to switching from the recording mode to the reproduction mode. A photoelectric conversion step for converting the optical image into an electrical signal;
A storage step of temporarily storing captured image information obtained by the photoelectric conversion step in a buffer memory;
Generating a recording header including a reduced image of the captured image information, and storing the header in the buffer memory following the captured image information; and
A reading step of first reading out a recording header from the buffer memory, and then reading out captured image information corresponding to the recording header;
An imaging apparatus control method comprising: a recording step of recording the recording header read from the buffer memory and the captured image information on a recording medium as one file,
When recording the recording header on the recording medium, do not release the area for storing the recording header of the buffer memory;
When recording the captured image information on the recording medium, releasing the storage area of the captured image information in the buffer memory according to the recording of the captured image information; and
An image pickup apparatus control method comprising: recording all of the read photographed image information on the recording medium, and then releasing a storage area of the recording header corresponding to the photographed image information.   The imaging apparatus control method according to claim 4, wherein the buffer memory is a ring buffer.   5. The imaging apparatus control method according to claim 4, further comprising an image display step for causing the image display means to display an image of the latest captured image information stored in the buffer memory in response to switching from the recording mode to the reproduction mode. .

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