JP4574426B2 - Data processing apparatus and data processing method - Google Patents

Description

  The present invention relates to a data processing apparatus and a data processing method for setting a read area and a write area on the same memory and writing data read from the read area to the write area.

Conventionally, a method has been proposed in which compressed image data compressed while reading original image data is overwritten on an area where original image data is stored in order to effectively use a storage area of a memory. For example, it is known that when there is no more free space in the memory, the original image data already stored in the memory is compressed and the compressed image data is overwritten and saved to secure the free space in the memory. ing. (See Patent Document 1)
JP 2002-374488 A

  However, for example, when JPEG compression is performed on image data that has been subjected to image processing from raw image data in RAW format, the size of the compressed image data may be larger than the size of the original image data or may be partially complicated. If there is data, the compressed image data may be written in the area of the original image data that has not yet been read.

  An object of the present invention is to provide a data processing apparatus and method for reading original image data and overwriting the compressed image data so that the compressed image data is not written in the area of the original image data that has not yet been read. It is to provide an apparatus and method.

In view of such a problem, the present invention sets a read area and a write area on the same memory, performs compression processing on the data read from the read area, and writes the compressed data to the write area again. a processor, a writing area setting means for setting a writing area of the compressed data compression processing is applied to the read data in a region that does not overlap the read area, the compressed data write area set Address acquisition means for acquiring the write address of the write area and the read address of the read area when the writing of is completed,
A determination unit that determines whether a difference between the acquired write address and the read address is equal to or less than a predetermined amount, and a difference between the write address and the read address is equal to or less than a predetermined amount, the write area setting unit Transfer means for transferring the compressed data from the head address of the write area set up to the write address acquired by the address acquisition means to the recording medium, and after the compressed data is transferred by the transfer means, the write area Based on the start address of the write area set by the setting means and the read address acquired by the address acquiring means, the write area is reset to the write area set by the write area setting means. And setting means.

  When setting the first write area, set the start address of the write area before the start address of the read area, and acquire the read address of the read area when it becomes impossible to write to the set write area, Since a write area for resetting the write area is set based on the acquired read address, a read area that has not yet been read is not set as the write area. Therefore, for example, when JPEG compression is performed, even if the size of the compressed image data is larger than the size of the original image data, the compressed image data may be written in the area of the original image data that has not yet been read. Absent.

  FIG. 1 is a diagram showing the configuration of an image processing apparatus embodying the present invention.

  In FIG. 1, reference numeral 100 denotes an image processing apparatus capable of imaging.

  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. Processing of the image processing parameter converted image from the original image is also performed here.

  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-emission) processing are performed.

  Further, the image processing circuit 20 performs predetermined arithmetic processing using 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, 28 denotes an image display unit including a TFT LCD, and the image data for display 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 image processing apparatus 100 can be greatly reduced. I can do it.

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 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.

  A compression / decompression circuit 32 compresses / 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. When data is transferred to compress / decompress data in the memory 30, or when data compressed / decompressed by the compression / decompression circuit 32 is transferred to the memory 30, the data is transferred by DMA (Direct Memory Access) by the memory control circuit. It can be performed.

  Reference numeral 40 denotes an 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. 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.

  Reference numeral 50 denotes a system control circuit that controls the entire image processing apparatus 100, and reference numeral 52 denotes a memory that 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. One or a plurality of places are provided near the portion where they are easily visible, and are configured by a combination of, for example, an LCD, an LED, a sound generation element, and the like.

  In addition, the display unit 54 is partially 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 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 and recording There are a display state of the media 200 and 210, a communication I / F operation display, a date / time display, a recording menu, and the like.

  Further, 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.

  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 by a first stroke of a shutter button (not shown), and includes AF (auto focus) processing, AE (automatic exposure) processing, AWB (auto white balance) processing, EF (flash pre-flash) processing, and the like. Instruct the start of operation.

  A shutter switch SW2 64 is turned on in a second stroke following a first stroke of a shutter button (not shown), and a signal read from the image sensor 12 is transferred to the memory 30 via the A / D converter 16 and the memory control circuit 22. Exposure processing for writing image data, development processing using computations in the image processing circuit 20 and the memory control circuit 22, reading out the image data from the memory 30, compression in the compression / decompression circuit 32, and recording on the recording medium 200 or 210 It instructs the start of a series of processes called recording processes for writing data.

  Reference numeral 66 denotes an image display ON / OFF switch that can set ON / OFF of the image display unit 28.

  With this function, when photographing is performed 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.

  Reference numeral 70 denotes an operation unit composed of various buttons, a touch panel, and the like. 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- (minus) button, shooting image quality selection button, exposure correction button, date / time setting button, and the like.

  Reference numeral 80 denotes a power supply control means, which includes 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 unit including the recording medium for a necessary period.

  Reference numeral 82 denotes a connector, 84 denotes a connector, and 86 denotes 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, an AC adapter, or the like.

  90 and 94 are interfaces with a recording medium such as a memory card or a hard disk, 92 and 96 are connectors for connecting to a recording medium such as a memory card or a hard disk, and 98 is a recording medium 200 or 210 attached to the connector 92 or 96. Recording medium attachment / detachment detecting means for detecting whether or not the recording medium is present.

  In this embodiment, it is assumed that there are two 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 and any number 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 a PCMCIA card, a CF (Compact Flash (registered trademark)) card, or the like that conforms to a standard.

  Further, when the interfaces 90 and 94 and the connectors 92 and 96 are configured using a PCMCIA card, a CF (Compact Flash (registered trademark)) card, or the like, a LAN card, a modem card, a USB card, IEEE1394. Image data and management information attached to image data are transferred to and from peripheral devices such as other computers and printers by connecting various communication cards such as cards, P1284 cards, SCSI cards, and PHS communication cards. I can meet each other.

  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 image processing apparatus 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.

  A communication unit 110 has various communication functions such as RS232C, USB, IEEE1394, P1284, SCSI, modem, LAN, and wireless communication.

  Reference numeral 112 denotes a connector for connecting the image processing apparatus 100 to another device by the communication unit 110 or an antenna in the case of wireless communication.

  Reference numeral 200 denotes a recording medium such as a memory card or a hard disk.

  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 image processing apparatus 100, and a connector 206 for connecting to the image processing apparatus 100.

  Reference numeral 210 denotes a recording medium such as a memory card or a hard disk.

  The recording medium 210 includes a recording unit 212 composed of a semiconductor memory, a magnetic disk, or the like, an interface 214 with the image processing apparatus 100, and a connector 216 that connects to the image processing apparatus 100.

  The operation of the image processing apparatus 100 will be described with reference to FIGS.

  FIG. 2 is a flowchart for explaining the operation when the compressed image data is overwritten on the original image data recorded in the memory 30. FIG. 3 is a diagram for explaining the arrangement of data in the memory 30.

  First, various settings are made for the compression / decompression circuit 32 (S201). Thereafter, the Read DMA setting for reading the original image data from the memory 30 to the compression / decompression circuit 32 and the Write DMA setting for writing the compressed data from the compression / decompression circuit 32 to the memory are performed (S202).

  The write DMA setting sets the start address of the write area and the write amount (size of the write area). The start address of the write area is set to be an address before the start address of the read area. Also, when the set write amount is reached, an interrupt process is generated and a write completion flag is set. Note that when writing processing is performed in units of blocks, the set writing amount may not completely match the writing amount that has actually been written, so writing the next block will exceed the set writing amount. Sometimes, an interrupt process is generated and a write completion flag is set.

  The DMA setting for Read sets the start address of the read area and the read amount (read area size). When the set read amount is reached, that is, when all the original image data is read, an interrupt process is generated and a read completion flag is set.

  FIG. 3A shows the write area and read area set in step S202. In FIG. 3A, the original image data is recorded in the area of addresses 0C0000H to FFFFFFH. Therefore, the read area set by the Read DMA setting is an area of addresses 0C0000H to FFFFFFH (area indicated by Read in the drawing). On the other hand, the write area set by the write DMA setting is set to 0A0000H, which is an address before the start address 0C0000H of the read area. The write amount is set to a difference from 0A0000H to the start address 0C0000H of the area where the original image data is recorded. That is, in this embodiment, 128 KB, which is the difference between 0A0000H and 0C0000H, is set as the write amount. In FIG. 3A, the area 1 is set as the writing area.

  Set the DMA of Read and Write, and proceed to Step S203. In step S203, the original image data is read sequentially from the read area start address 0C0000H, and after compression processing by the compression / decompression circuit 32, the compressed image data is written from the write area start address 0A0000H. In step S204, there is an interrupt process that occurs when writing to the writing area reaches the set writing amount (writing completion) or when reading from the reading area reaches the setting reading amount (reading completion). If interrupt processing occurs, the process proceeds to step S205, and if not, step S204 is repeated.

  In step S205, it is determined whether or not the interrupt processing that has occurred is completion of reading from the reading area. Here, when it is determined that the reading from the reading area is completed, the process ends. On the other hand, if it is determined that the writing to the set writing area is completed, the process proceeds to step S206.

  In step S206, the write address and read address when the interrupt process occurs are acquired. Here, the write address is the end address of the write area when the write amount to the write area reaches the set write amount. When the writing process is performed in block units, it is the end address at which the last writing process was performed.

  The read address is the address of the read area when the write process reaches the end address of the write area. That is, the read address indicates how far the read area has been read when writing to the end of the write area.

  Then, it is determined whether or not the capacity indicated by the difference between the read address and the write address exceeds a predetermined capacity. The difference between the read address and the write address represents how much data has been read before the set write area is full.

  Referring to FIG. 3A, when the area 1 set as the write area becomes full, the read area reads to the address 0DFFFFH. At this time, if the end address of region 1 is 0BFFFFH, it is determined whether or not the capacity indicated by the difference between 0DFFFFH and 0BFFFFH exceeds a predetermined capacity (for example, 100 KB).

  If the capacity indicated by the difference between the read address and the write address exceeds a predetermined capacity, the process proceeds to step S211. If the capacity indicated by the difference between the read address and the write address is equal to or less than the predetermined capacity, the process proceeds to step S211. Proceed to step S208.

  First, a case where the capacity indicated by the difference between the read address and the write address exceeds a predetermined capacity will be described.

  In step S211, a new DMA setting of Write is performed. Here, the write DMA setting is performed so that the read area that has been read in the previous compression transfer process becomes a new write area.

  This will be described with reference to FIGS. 3 (a) and 3 (b). In FIG. 3A, in the first Write DMA setting, area 1 (0A0000H to 0BFFFFH) is set as a writing area, and original image data recorded in area 2 (0C0000H to 0DFFFFH) in the reading area. Compressed and transferred. In the second Write DMA setting, area 2 (0C0000H to 0DFFFFH) is set as a new writing area, as shown in FIG. 3B. In this way, Write DMA setting is performed, and the process proceeds to step S210.

  In step S210, reading of the original image data is started from the address next to the read address acquired in step S206, compression is performed by the compression / decompression circuit 32, and compression is performed from the head address of the newly set write area. Write the image data.

  Referring to FIG. 3B, reading of the original image data starts from the address 0E0000H next to the read address 0DFFFFH acquired in step S206, and is compressed to the area 2 (0C0000H to 0DFFFFH) newly set as the writing area. The image data is written, and the process returns to step S204.

  When the write amount set in the area 2 is written, interrupt processing occurs again. If the original image data whose read address is the end address of the area 3 is read when the interrupt processing occurs, the end address 0DFFFFH of the area 2 is compared with the end address 0FFFFFH of the area 3. When the capacity indicated by the difference between 0DFFFFH and FFFFFH exceeds the predetermined capacity, the area 3 is set as the next writing area by the write DMA setting as shown in FIG. Read.

  When the processing from step S204 to step S211 is repeated and all the original image data in the read area is read, an interrupt process occurs. If it is determined in step S205 that the interrupt process is complete when reading from the read area, the flowchart ends.

  Next, a case where the capacity indicated by the difference between the read address and the write address is equal to or less than a predetermined capacity will be described.

  In FIG. 3C, the write amount set in area 3 is written, and interrupt processing occurs again. If the original image data whose read address is the end address of the area 4 is read when the interrupt process occurs, the end address 0FFFFFH of the area 3 is compared with the end address 103FFFH of the area 4 in step S206. Since the capacity indicated by the difference between 0FFFFFH and 103FFFH is equal to or less than the predetermined capacity (100 KB), the process proceeds to step S208.

  In step S208, all the recorded compressed image data is moved to the recording medium 200 or the recording medium 210, and the process proceeds to step S209. In FIG. 3C, all the compressed image data recorded in the areas 1, 2, and 3 are moved to the recording medium 200 or the recording medium 210.

  In step S209, Write DMA setting is performed again. Here, a new write area is set from the start address of the area initially set as the write area in step S202 to the read address acquired in step S206. Referring to FIG. 3D, the area from the start address 0A0000H of area 1 to the end address 103FFFH of area 4 is set as the write area.

  When all of the original image data in the reading area is read by repeating the processing from step S204 to step S211, interrupt processing occurs. If it is determined in step S205 that the interrupt process is complete when reading from the read area, the flowchart ends.

  Since the write area is set in this way, the write address does not overtake the read address. When the capacity indicated by the difference between the write address and the read address approaches a predetermined capacity, all the compressed image data recorded in the memory 30 is moved to the storage media 200 and 210, and then the original image data is compressed. Since the process is resumed, there is no shortage of the writing area during the process.

It is a block diagram of a configuration of an embodiment of the present invention. It is a flowchart of a present Example. It is a figure which shows the data arrangement | positioning of the memory of a present Example.

Explanation of symbols

30 memory 32 image compression / decompression circuit 50 system control circuit 200 recording medium 210 recording medium

Claims (4)

A data processing apparatus that sets a read area and a write area on the same memory, performs compression processing on data read from the read area, and writes the compressed data to the write area again .
A write area setting means for setting a write area for compressed data obtained by performing compression processing on the read data in an area that does not overlap with a read area;
Address acquisition means for acquiring the write address of the write area and the read address of the read area when the writing of the compressed data is completed in the set write area;
Determining means for determining whether or not a difference between the acquired write address and the read address is equal to or less than a predetermined amount;
When the difference between the write address and the read address is a predetermined amount or less, the compressed data from the start address of the write area set by the write area setting means to the write address acquired by the address acquisition means Transfer means for transferring to a recording medium;
After the compressed data is transferred by the transfer means, the write area setting means sets based on the start address of the write area set by the write area setting means and the read address acquired by the address acquisition means And a write area resetting means for resetting a write area in the written area. 2. The data processing apparatus according to claim 1 , wherein the write area setting means sets the start address of the write area before the start address of the read area. The write area resetting means resets the write area based on the read address acquired by the address acquisition means when the difference between the write address and the read address is larger than a predetermined amount. Item 3. The data processing device according to Item 1 or 2 . A data processing method that sets a read area and a write area on the same memory, performs compression processing on data read from the read area, and writes the compressed data to the write area again .
A writing area setting step for setting a writing area for compressed data in which compression processing is performed on the read data in an area that does not overlap with a reading area;
An address acquisition step of acquiring a write address of the write area and a read address of the read area when writing of the compressed data is completed in the set write area;
A determination step of determining whether a difference between the acquired write address and the read address is equal to or less than a predetermined amount;
When the difference between the write address and the read address is a predetermined amount or less, the compressed data from the start address of the write area set in the write area setting step to the write address acquired by the address acquisition unit Transferring to the recording medium;
After the compressed data is transferred in the transfer step, the write region is set in the write region based on the start address of the write region set in the write region setting step and the read address acquired in the address acquisition step And a writing area resetting step for resetting the writing area set in step (1).

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