JP3605084B2 - Image data correction device, image processing device, image data correction method, program, and storage medium - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image data correction device that corrects image data obtained from an image sensor, an image processing device including an image sensor that captures, records, and reproduces a still image or a moving image, a pixel correction method, a program, and a storage medium About.
[0002]
[Prior art]
2. Description of the Related Art Conventionally, an image processing apparatus such as an electronic camera that records and reproduces a still image or a moving image captured by a solid-state imaging device (hereinafter, an imaging device) such as a CCD or a CMOS using a memory card having a solid-state memory device as a recording medium is already available. It is commercially available. According to this type of image processing apparatus such as an electronic camera, the photographer selects a single-shot / continuous-shot shooting mode from the operation unit, so that each time the shutter button is pressed, a single shot is shot. It is possible to perform shooting by switching between shooting and continuous shooting in which shooting is performed continuously while the shutter button is kept pressed.
[0003]
When an image is captured using an image sensor such as a CCD or a CMOS in an image processing apparatus, dark image data read out after charge accumulation is performed in the same manner as in actual shooting without exposing the image sensor, and the image sensor is exposed. The dark noise correction processing can be performed by performing an arithmetic processing using the actual captured image data read after the charge accumulation is performed in the state where the electric charge is stored. Accordingly, with respect to image quality deterioration such as pixel current loss due to dark current noise generated by the image sensor or minute scratches inherent to the image sensor, it is possible to correct high quality images by correcting captured image data. On the other hand, in order for the image processing apparatus to perform the dark noise correction processing, a dark image must be taken without fail, so that a release time lag is increased and a valuable shutter chance is missed.
[0004]
In order to solve this problem, noise components such as horizontal shading (luminance level unevenness) and dark current (offset with respect to an appropriate dark level) of the image sensor are canceled using correction data stored in advance. There is known an image processing apparatus capable of capturing a high-quality image so that the release time lag does not become too large.
[0005]
The above-mentioned pre-stored correction data is mainly used for performing dark shooting without correcting the correction data at the time of assembling the image processing apparatus. Offset amount that cancels the shading of Since the dark level is a reference for the luminance component and the color component of the image data when performing image processing, it must be corrected so that the dark level of the image data obtained by exposing the image sensor is appropriate. Will improve the quality of the image quality.
[0006]
[Problems to be solved by the invention]
However, the prior art described above has the following problems. For some imaging devices, the state of the dark current noise varies non-linearly depending on the temperature characteristics of the output circuit unit. In the case of an image processing apparatus having such an imaging system, even if a correction value stored in advance is used, noise components that should have been canceled remain in the captured image data, degrading image quality. I will. In this case, performing the correction by the calculation using the temperature coefficient complicates the form of the calculation, and if the number of pixels of the image sensor is large, the calculation takes a long time and the release time lag increases. It is also conceivable to store the correction value in advance for each temperature region, but this requires more memory capacity, and thus the device becomes larger.
[0007]
The present invention has been made in view of the above points, and even if the characteristics of an imaging system change due to the influence of environmental temperature, it is possible to prevent a release time lag associated with dark image shooting from increasing and to improve image quality. It is an object of the present invention to provide an image data correction device, an image processing device, an image data correction method, a program, and a storage medium that can prevent deterioration and obtain a high-quality image.
[0008]
[Means for Solving the Problems]
In order to achieve the above object, the image data correction apparatus of the present invention stores image data obtained from an imaging unit that converts an optical image into an electric signal, in a memory.Offset amount for one horizontal lineAn image data correction device that corrects using correction data, wherein the image data is stored in the memory in accordance with a change in image data obtained in a first imaging mode in which charge is accumulated without exposing the imaging unit. Changing means for changing the correction data, and image data obtained in a second imaging mode in which charge is stored in a state where the imaging means is exposed, using the corrected correction data changed by the changing means. The image data obtained in the first imaging mode is noise data obtained by extracting a part of the imaging means.
[0009]
Further, an image processing apparatus according to the present invention includes the image data correction apparatus and the imaging unit.
[0010]
Further, the image data correction method of the present invention stores the image data in the memory corresponding to the fluctuation of the image data obtained in the first imaging mode in which the charge is accumulated without exposing the imaging means for converting the optical image into an electric signal. For correction of stored image dataOffset amount for one horizontal lineAn image data correction method for changing correction data, and correcting image data obtained in a second imaging mode in which charge is accumulated in a state where the imaging unit is exposed, using the corrected correction data, The image data obtained in the first imaging mode is noise data obtained by extracting a part of the imaging means.
[0011]
Further, the program of the present invention is stored in the memory in accordance with the fluctuation of the image data obtained in the first imaging mode in which the charge is accumulated without exposing the imaging means for converting the optical image into an electric signal. For image data correctionOffset amount for one horizontal lineA program comprising: a step of changing correction data; and a step of correcting image data obtained in a second imaging mode in which charge is accumulated in a state where the imaging unit is exposed, using the corrected correction data. The image data obtained in the first imaging mode is noise data obtained by extracting a part of the imaging unit.
[0012]
Further, a storage medium of the present invention stores the program.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[0014]
FIG. 1 is a block diagram illustrating a configuration of an image processing apparatus according to an embodiment of the present invention. The image processing apparatus includes an image processing apparatus (main body) 100, a recording medium 200 and a recording medium 210 detachably mounted on the image processing apparatus main body, and a lens unit 300 removably mounted on the image processing apparatus main body. It has.
[0015]
More specifically, the shutter 12 controls the amount of exposure to the image sensor 14. The image sensor 14 converts an optical image of a subject into an electric signal. The image processing apparatus 100 according to the present embodiment has a first imaging mode in which charge accumulation is performed without exposing the imaging device 14 and a second imaging mode in which charge accumulation is performed with the imaging device 14 exposed. The light beam that has entered the lens 310 of the lens unit 300 is guided by the single-lens reflex system via the stop 312, the lens mount 306, the lens mount 106 of the image processing apparatus 100, the mirror 130, and the shutter 12, and as an optical image. Can be imaged on. The A / D converter 16 converts an analog signal output of the image sensor 14 into a digital signal. The timing generation circuit 18 supplies a clock signal and a control signal to the imaging device 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.
[0016]
The image processing circuit 20 performs predetermined pixel interpolation processing and color conversion processing on data from the A / D converter 16 or data from the memory control circuit 22. In the image processing circuit 20, if necessary, predetermined arithmetic processing is performed using the captured image data, and based on the obtained arithmetic result, the system control circuit 50 causes the shutter control means 40, the distance measurement control means TTL (through-the-lens) type AF (autofocus) processing, AE (automatic exposure) processing, and EF (flash dimming) processing, which perform control for 42, can be performed. Further, the image processing circuit 20 performs predetermined arithmetic processing using the captured image data, and also performs TTL AWB (auto white balance) processing based on the obtained arithmetic result.
[0017]
In the present embodiment, since the image processing apparatus is provided with the distance measuring means 42 and the light measuring means 46 exclusively, the AF (auto focus) processing and the AE ( Each processing of the automatic exposure) processing and the EF (flash light control) processing is performed, and each processing of the AF (auto focus) processing, the AE (auto exposure) processing, and the EF (flash light control) processing using the image processing circuit 20 is performed. May not be performed. Alternatively, AF (auto focus) processing, AE (auto exposure) processing, and EF (flash light control) processing are performed using the distance measuring means 42 and the light measuring means 46, and the image processing circuit 20 is used. Each of AF (auto focus) processing, AE (auto exposure) processing, and EF (flash light control) processing may be performed.
[0018]
The 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 sent to 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 sent directly to the image display memory 24 or the memory 30 via the memory control circuit 22. Written. The image display memory 24 stores image data for display. The D / A converter 26 converts a digital signal output of the memory control circuit 22 into an analog signal. The image display unit 28 is configured by a TFT LCD or the like, and display image data written in the image display memory 24 is displayed by the image display unit 28 via the D / A converter 26. If the captured image data is sequentially displayed using the image display unit 28, the electronic finder function can be realized. The image display unit 28 can arbitrarily turn on / off the display in accordance with 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 significantly reduced. Can be.
[0019]
The memory 30 is 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 moving image for a predetermined time. Accordingly, even in the case of continuous shooting or panoramic shooting in which a plurality of still images are continuously shot, it is possible to write a large amount of images to the memory 30 at high speed. The memory 30 can also be used as a work area of the system control circuit 50. The compression / decompression circuit 32 compresses and decompresses image data by adaptive discrete cosine transform (ADCT) or the like. The compression / decompression circuit 32 reads an image stored in the memory 30 and performs a compression process or a decompression process. Write to memory 30.
[0020]
The shutter control unit 40 controls the shutter 12 based on the photometric information from the photometric unit 46 in cooperation with the aperture control unit 340 that controls the aperture 312. The distance measuring means 42 is for performing AF (autofocus) processing, and converts a light beam incident on the lens 310 of the lens unit 300 into an aperture 312, a lens mount 306, and an image processing apparatus 100 by a single-lens reflex method. By allowing the light to enter the distance measuring means 42 via the lens mount 106, the mirror 130, and the distance measuring sub-mirror (not shown), the in-focus state of the image formed as an optical image can be measured. The thermometer 44 can detect the temperature of the shooting environment. When the thermometer 44 is inside the sensor (the image sensor 14), it is possible to more accurately predict the dark current of the sensor.
[0021]
The photometric unit 46 is for performing an AE (automatic exposure) process, and converts a light beam incident on the lens 310 of the lens unit 300 into an aperture 312, a lens mount 306, and a lens of the image processing apparatus 100 by a single-lens reflex method. By allowing the light to enter the photometric unit 46 via the mount 106, the mirrors 130 and 132, and a photometric lens (not shown), the exposure state of the image formed as an optical image can be measured. The light metering means 46 also has an EF (flash light control) processing function in cooperation with the flash 48. The flash 48 also has a function of projecting AF auxiliary light and a function of controlling flash light.
[0022]
The system control circuit 50 controls the shutter control means 40, the aperture control means 340, and the distance measurement control means 342 based on the calculation result obtained by calculating the image data picked up by the image pickup element 14 by the image processing circuit 20. Exposure control and AF (autofocus) control can also be performed using the video TTL method. Furthermore, AF (autofocus) control may be performed by using both the measurement result by the distance measuring unit 42 and the calculation result obtained by calculating the image data captured by the image sensor 14 by the image processing circuit 20. Then, the exposure control may be performed by using both the measurement result by the photometry unit 46 and the calculation result obtained by calculating the image data captured by the image sensor 14 by the image processing circuit 20.
[0023]
The system control circuit 50 controls the entire image processing apparatus 100, and executes processing shown in each flowchart described below based on a program stored in the memory 52. The memory 52 is a memory for storing constants, variables, programs, and the like for operation of the system control circuit 50. The display unit 54 includes a liquid crystal display device, a speaker, and the like that display and output an operation state and a message using characters, images, sounds, and the like in accordance with execution of a program in the system control circuit 50. A single or a plurality of such units are installed at easily visible positions near the operation unit of the image processing apparatus 100, and are configured by, for example, a combination of an LCD, an LED, and a sound generating element. The display unit 54 has a part of its functions installed in the optical finder 104.
[0024]
Of the display contents of the display unit 54, those displayed on the LCD or the like include, for example, a single shot / continuous shooting display, a self-timer display, a compression ratio display, an ISO (International Organization for Standardization) sensitivity display, and a recording pixel number display. , Record count display, remaining shot count 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, information display with a plurality of digits, display of attachment / detachment status of recording media 200 and 210, attachment / detachment status indication of lens unit 300, communication interface operation display, date / time display, display showing connection status with external computer, etc. There is.
[0025]
Further, among the display contents of the display unit 54, those displayed in the optical viewfinder 104 include, for example, a focus display, a shooting ready display, a camera shake warning display, a flash charge display, a flash charge completion display, a shutter speed display, There are an aperture value display, an exposure correction display, a recording medium writing operation display, and the like. Further, among the display contents of the display unit 54, those displayed on the LED or the like include, for example, an in-focus display, a shooting ready display, a camera shake warning display, a camera shake warning display, a flash charge display, a flash charge completion display, and a recording medium. There are a writing operation display, a macro shooting setting notification display, a secondary battery charge state display, and the like. Further, among the display contents of the display unit 54, those displayed on a lamp or the like include, for example, a self-timer notification lamp. This self-timer notification lamp may be shared with the AF auxiliary light.
[0026]
The non-volatile memory 56 is an electrically erasable / recordable memory, for example, an EEPROM or the like. The nonvolatile memory 56 stores various parameters, setting values such as ISO sensitivity, setting modes, and one-dimensional correction data used when performing horizontal dark shading correction. The one-dimensional correction data is created and written at the time of adjustment in the manufacturing process of the image processing apparatus.
[0027]
The operation means 60, 62, 64, 66, 68, 69, and 70 are for inputting various operation instructions of the system control circuit 50, and include switches, dials, touch panels, pointing by gaze detection, voice recognition devices, and the like. , Or a combination of two or more. Here, these operation means will be specifically described.
[0028]
The mode dial switch 60 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 view shooting mode, and a panorama shooting mode can be switched and set. The shutter switches SW1 and 62 are turned on during the operation of a shutter button (not shown) to perform AF (auto focus) processing, AE (auto exposure) processing, AWB (auto white balance) processing, EF (flash light control) processing, and the like. Instruct operation start.
[0029]
The shutter switches SW2 and 64 are turned on when the operation of a shutter button (not shown) is completed, and an exposure process for writing a signal read from the image sensor 14 to the memory 30 via the A / D converter 16 and the memory control circuit 22 is performed. A development process using an operation in the image processing circuit 20 or the memory control circuit 22; a recording process in which image data is read from the memory 30, compressed by the compression / decompression circuit 32, and written into the recording medium 200 or 210. Instructs the start of a series of processing operations. The reproduction switch 66 instructs the start of a reproduction operation for reading a captured image from the memory 30 or the recording medium 200 or 210 and displaying the image on the image display unit 28 in the shooting mode.
[0030]
The single shooting / continuous shooting switch 68 performs a single shooting mode in which a single frame is shot when the shutter switch SW2 · 64 is pressed and enters a standby state, and shooting is continuously performed while the shutter switch SW2 / 64 is pressed. A continuous shooting mode can be set. The ISO sensitivity setting switch 69 can set the ISO sensitivity (photographing sensitivity) by changing the gain setting in the image sensor 14 or the image processing circuit 20.
[0031]
The operation unit 70 includes various buttons, a touch panel, and the like, and includes a menu button, a set button, a macro button, a multi-screen playback page break button, a flash setting button, a single-shot / continuous-shot / self-timer switching button, and a menu shift + (Plus) button, menu 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 switch buttons for setting selection and switching of various functions when executing and reproducing, a determination / execution button for setting and executing various functions when performing shooting and reproduction of a panoramic mode, etc., and an image display unit Image display ON / OFF switch for setting ON / OFF of 28, image taken immediately after shooting It is equipped with a quick review ON / OFF switch for setting a quick review function of automatically playing back data.
[0032]
The operation unit 70 is a compression mode which is a switch for selecting a compression rate of JPEG (Joint Photographic Expert Group) compression or for selecting a CCD RAW mode for digitizing a signal of the image pickup device 4 as it is and recording it on a recording medium. Switch, a reproduction mode, a multi-screen reproduction / erasure mode, a reproduction switch capable of setting various function modes such as a PC (personal computer) connection mode, and the like. An AF mode setting switch or the like that can set a one-shot AF mode that maintains the in-focus state after focusing and a servo AF mode that continues auto-focus operation while the shutter switch SW1 is pressed. is thereThe functions of the plus button and the minus button are provided with a rotary dial switch so that numerical values and functions can be more easily selected.
[0033]
The power switch 72 can switch between power-on and power-off modes of the image processing apparatus 100. The power switch 72 can also be set to switch on and off the power of various attached devices such as the lens unit 300 connected to the image processing apparatus 100, the external strobe, and the recording media 200 and 210. The power control unit 80 is configured by a battery detection circuit, a DC-DC converter, a switch circuit for switching a block to be energized, and the like, and detects whether or not a battery is mounted, the type of the battery, and the remaining amount of the battery. The DC-DC converter is controlled based on an instruction from the system control circuit 50, and a required voltage is supplied to each unit including a recording medium for a required period. The connectors 82 and 84 connect the power supply control means 80 and the power supply means 86. The power supply unit 86 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.
[0034]
The interfaces 90 and 94 control interfaces with recording media 200 and 210 such as a memory card and a hard disk. Connectors 92 and 96 connect the image processing apparatus 100 to recording media 200 and 210 such as a memory card and a hard disk. The recording medium attachment / detachment detecting means 98 detects whether the recording medium 200 or the recording medium 210 is attached to the connector 92 and the connector 96, or the connector 92 or the connector 96.
[0035]
In this embodiment, the description has been made assuming that there are two interfaces and connectors for attaching a recording medium. Of course, the interface and the connector for attaching the recording medium may have a single or plural number of systems. Further, a configuration may be adopted in which interfaces and connectors of different standards are provided in combination. The interface and the connector may be configured using a standard such as a PCMCIA (Personal Computer Memory Card International Association) card or a CF (Compact Flash (registered trademark)) card.
[0036]
Further, when the interfaces 90 and 94 and the connectors 92 and 96 are configured by using a standard such as a PCMCIA card or a CF (Compact Flash (registered trademark)) card, a LAN card, a modem card, a USB (Universal Serial), and the like are used. Bus) card, IEEE (Institute of Electronic and Electronic S Engineers) 1394 card, P1284 card, SCSI (Small Computer System Interface) card, PHS (Personal Handyphone etc.), PHS (Personal Handyphone), etc. Image data is transferred between the image processing device and other peripheral devices such as computers and printers. It can be mutually transferred management information attached to the image data.
[0037]
The optical finder 104 guides a light beam incident on the lens 310 of the lens unit 300 through the stop 312, the lens mount 306, the lens mount 106 of the image processing apparatus 100, and the mirrors 130 and 132 by a single-lens reflex method. As an image. Thus, it is possible to perform photographing using only the optical viewfinder 104 without using the electronic viewfinder function of the image display unit 28. Further, in the optical finder 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 provided.
[0038]
The communication unit 110 has various communication functions such as RS232C, USB, IEEE1394, P1284, SCSI, modem, LAN, wireless communication, and the like. The connector / antenna 112 functions as a connector when the image processing apparatus 100 is connected to another device by the communication unit 110, and functions as an antenna for wireless communication. The interface 120 is an interface for connecting the image processing apparatus 100 to the lens unit 300 in the lens mount 106.
[0039]
The connector 122 electrically connects the image processing device 100 to the lens unit 300. The lens attachment / detachment detection unit 124 detects whether or not the lens unit 300 is attached to the lens mount 106 and / or the connector 122. The connector 122 transmits a control signal, a status signal, a data signal, and the like between the image processing apparatus 100 and the lens unit 300, and has a function of supplying currents of various voltages. Further, the connector 122 may be configured to transmit not only electric communication but also optical communication, voice communication, and the like. The mirrors 130 and 132 can guide the light beam incident on the lens 310 to the optical finder 104 by a single-lens reflex method. Note that the mirror 132 may have either a quick return mirror configuration or a half mirror configuration.
[0040]
The recording medium 200 includes a memory card, a hard disk, and the like. The recording medium 200 includes a recording unit 202 including a semiconductor memory or a magnetic disk, an interface 204 with the image processing apparatus 100, and a connector 206 for connecting to the image processing apparatus 100. The recording medium 210 includes a memory card, a hard disk, and the like. The recording medium 210 includes a recording unit 212 including a semiconductor memory or a magnetic disk, an interface 214 with the image processing device 100, and a connector 216 for connecting to the image processing device 100.
[0041]
The lens unit 300 is configured as an interchangeable lens type. The lens mount 306 mechanically couples the lens unit 300 with the image processing apparatus 100. The lens mount 306 includes various functions for electrically connecting the lens unit 300 to the image processing apparatus 100. The taking lens 310 captures a subject image. The aperture 312 adjusts the amount of light entering from the taking lens 310. The interface 320 controls an interface for connecting the lens unit 300 to the image processing apparatus 100 in the lens mount 306. The connector 322 electrically connects the lens unit 300 to the image processing apparatus 100. The connector 322 transmits a control signal, a status signal, a data signal, and the like between the image processing apparatus 100 and the lens unit 300, and also has a function of supplying or supplying a current of various voltages. Further, the connector 322 may be configured to transmit not only electric communication but also optical communication, voice communication, and the like.
[0042]
The aperture control unit 340 controls the aperture 312 based on photometric information from the photometric unit 46 of the image processing apparatus 100 in cooperation with the shutter control unit 40 that controls the shutter 12. The distance measurement control unit 342 controls focusing of the photographing lens 310. The zoom control unit 344 controls zooming of the photographing lens 310. The lens system control circuit 350 controls the entire lens unit 300. The lens system control circuit 350 includes a memory for storing operation constants, variables, programs, and the like, identification information such as a number unique to the lens unit 300, management information, and function information such as an open aperture value, a minimum aperture value, and a focal length. It also has a function of a non-volatile memory for holding current and past set values.
[0043]
Next, the operation of the image processing apparatus 100 according to the present embodiment configured as described above will be described in detail with reference to FIGS.
[0044]
<Main Routine of Image Processing Apparatus 100>
2 and 3 are flowcharts of a main routine of the image processing apparatus 100 according to the present embodiment. The operation of the image processing apparatus 100 will be described with reference to FIGS. When the image processing apparatus 100 is powered on, for example, by replacing a battery, the system control circuit 50 initializes flags such as a single shooting / continuous shooting flag, a flash flag, and the like, control variables, and the like, which are necessary for each unit of the image processing apparatus 100. A predetermined initial setting is performed (step S101). Next, the system control circuit 50 determines the setting position of the power switch 72 (step S102).
[0045]
If the power switch 72 has been set to power OFF ("power OFF" in step S102), the display on each display unit is changed to the end state, and necessary parameters, setting values, settings including flags, control variables, and the like are set. The mode is recorded in the non-volatile memory 56, and predetermined termination processing such as shutting off unnecessary power of each unit of the image processing apparatus 100 including the image display unit 28 by the power supply control unit 80 is performed (Step S103), and then Step S102 is performed. Return to If the power switch 72 has been set to power ON ("power ON" in step S102), the system control circuit 50 uses the power control means 80 to determine the remaining capacity and operation status of the power source 86 composed of a battery or the like. It is determined whether there is a problem in the operation of the image processing apparatus 100 (step S104).
[0046]
If there is a problem with the power supply 86 (NO in step S104), a predetermined warning display output or a warning voice output is performed using an image or sound using the display unit 54 (step S105), and the process returns to step S102. If there is no problem with the power supply 86 (YES in step S104), the system control circuit 50 determines the setting position of the mode dial switch 60 (step S106). If the mode dial switch 60 has been set to the shooting mode ("Shooting mode" in step S106), the process proceeds to step S108. If the mode dial switch 60 has been set to another mode ("other mode" in step S106), the system control circuit 50 executes a process according to the selected mode (step S107), and executes the process. Upon completion, the process returns to the step S102.
[0047]
When the mode dial switch 60 is set to the photographing mode, the system control circuit 50 determines whether the recording medium 200 or 210 is mounted on the image processing apparatus 100, and determines whether the image data recorded on the recording medium 200 or 210 Then, it is determined whether the operation state of the recording medium 200 or 210 has a problem in the operation of the image processing apparatus 100, particularly, in the operation of recording and reproducing image data on the recording medium (step S108). As a result of the determination, if there is a problem (NO in step S108), a predetermined warning display output or a warning voice output is performed using an image or sound using the display unit 54 (step S105), and the process returns to step S102. . As a result of the determination, if there is no problem (YES in step S108), the process proceeds to step S109.
[0048]
Next, the system control circuit 50 checks the setting state of the single shooting / continuous shooting switch 68 for setting single shooting / continuous shooting (step S109). The continuous shooting flag is set to single shooting (step S110). If continuous shooting is selected, the single shooting / continuous shooting flag is set to continuous shooting (step S111). Proceed to step S121. According to the single shooting / continuous shooting switch 68, a single shooting mode in which one frame is shot when the shutter switch SW2 · 64 is pressed and a standby state is set, and continuous shooting while the shutter switch SW2 · 64 is pressed. Can be arbitrarily switched between the continuous shooting mode and the continuous shooting mode. The state of the single / continuous shooting flag is stored in the internal memory of the system control circuit 50 or the memory 52.
[0049]
Next, the system control circuit 50 performs display output and audio output of various setting states of the image processing apparatus 100 using images and audio using the display unit 54 (step S112). If the image display of the image display unit 28 is ON, the display and audio output of various setting states of the image processing apparatus 100 are performed by the image display unit 28 using images and voices.
[0050]
Next, the system control circuit 50 checks the state of the shutter switches SW1 and 62 (step S121). If the shutter switches SW1 and 62 are not pressed (“OFF” in step S121), the process returns to step S102. If the shutter switches SW1 and SW62 are pressed (“ON” in step S121), the system control circuit 50 performs a distance measurement process, focuses the photographing lens 310 on the subject, performs a photometry process, and executes an aperture value and Distance measurement and photometry processing for determining the shutter time is performed (step S122), and the process proceeds to step S123. In the photometric processing, the flash setting is also performed if necessary. The details of the distance measurement / photometry processing step S122 will be described later with reference to FIG.
[0051]
Next, the system control circuit 50 reads the one-dimensional correction data used for performing the horizontal dark shading correction from the non-volatile memory 56 and expands the data in the memory 30. After the development of the one-dimensional correction data is completed, dark capture using the one-dimensional correction data (indicating the accumulated charge output of the image sensor 14 with the shutter 12 closed in the first imaging mode) is performed. The developed correction data is changed according to the state of the dark image (step S123). Details of step S123 will be described later with reference to FIG.
[0052]
Next, the system control circuit 50 checks the state of the shutter switches SW2 64 (Step S124). If the shutter switches SW2 64 are not pressed (“OFF” in Step S124), the process proceeds to Step S125. If the shutter switches SW1 and SW62 have not been pressed, the process immediately returns to step S102. If the shutter switches SW1 and SW62 have been pressed, the process returns to step S124. If the shutter switches SW2 and 64 are pressed (“ON” in step S124), the system control circuit 50 determines whether or not the memory 30 has an image storage buffer area capable of storing image data captured in the second imaging mode. It is determined whether or not it is (step S126).
[0053]
If there is no area capable of storing new image data in the image storage buffer area of the memory 30 (NO in step S126), a predetermined warning display output or a warning sound output is performed using the display unit 54 by using an image or sound. After that (step S127), the process returns to step S102. For example, immediately after performing the maximum number of continuous shootings that can be stored in the image storage buffer area of the memory 30, the first image to be read from the memory 30 and written to the storage medium 200 or 210 is still stored in the storage medium 200 or 210. An example of this state is a state in which recording has not been performed, and one empty area cannot be secured in the image storage buffer area of the memory 30 yet.
[0054]
When the captured image data is stored in the image storage buffer area of the memory 30 after being subjected to the compression process, the image data can be stored in consideration of the fact that the amount of compressed image data differs according to the setting of the compression mode. It is determined in step S126 whether or not the area is on the image storage buffer area of the memory 30.
[0055]
If there is an image storage buffer area capable of storing the captured image data in the memory 30 (YES in step S126), the system control circuit 50 reads out the image pickup signal that has been imaged and stored for a predetermined time from the image sensor 14, and A photographing process for writing photographed image data in a predetermined area of the memory 30 via the / D converter 16, the image processing circuit 20, and the memory control circuit 22, or directly from the A / D converter 16 via the memory control circuit 22 Is executed (step S128). Details of the photographing processing step S128 will be described later with reference to FIGS.
[0056]
Next, the system control circuit 50 reads out a part of the image data written in a predetermined area of the memory 30 via the memory control circuit 22 and performs a WB (white balance) integration calculation process required for performing the development process. , OB (optical black) integration calculation processing, and stores the calculation result in the internal memory of the system control circuit 50 or the memory 52. Then, the system control circuit 50 uses the memory control circuit 22 and, if necessary, the image processing circuit 20 to read the captured image data written in a predetermined area of the memory 30 and read the captured image data into the internal memory or the memory of the system control circuit 50. Various development processes including AWB (auto white balance) process, gamma conversion process, and color conversion process are performed using the calculation results stored in the storage device 52 (step S129).
[0057]
Further, in the developing process, the dark correction is performed in step S123 and the subtraction process is performed using the correction data changed according to the state of the dark capture data, thereby canceling the dark current noise and the like of the image sensor 14. The arithmetic processing is also performed. If the dark correction calculation processing using the horizontal dark shading correction data is performed, the captured image is corrected without performing the dark capture processing with respect to image quality deterioration due to horizontal dark current noise or fixed pattern noise generated by the image sensor 14. be able to.
[0058]
Then, the system control circuit 50 reads out the image data written in the predetermined area of the memory 30, performs image compression processing according to the set mode by the compression / decompression circuit 32 (step S 130), and stores the image in the memory 30. The image data that has been photographed and has undergone a series of processing is written in the empty image portion of the buffer area. With the execution of a series of photographing operations, the system control circuit 50 reads out the image data stored in the image storage buffer area of the memory 30 and sends the image data to a memory card or a compact flash (registered) via the interface 90 or 94 and the connector 92 or 96. A recording process for writing data on the recording medium 200 or 210 such as a trademark card is started (step S131).
[0059]
This recording start process is performed on the image data each time new image data is written in the empty image portion of the image storage buffer area of the memory 30 after the photographing and the series of processes are completed. Note that while the image data is being written to the recording medium 200 or 210, a recording medium writing operation display such as blinking of an LED is performed on the display unit 54 in order to clearly indicate that the writing operation is being performed.
[0060]
Next, the system control circuit 50 determines whether or not the shutter switches SW1 and SW62 have been pressed (step S132). If the shutter switches SW1 and SW62 have not been pressed, the process returns to step S102. If the shutter switches SW1 and SW62 have been pressed, the state of the single / continuous shooting flag stored in the internal memory of the system control circuit 50 or the memory 52 is determined (step S133). If single shooting has been set, the process returns to step S132 and waits until the shutter switches SW1 and SW62 are turned off. If continuous shooting has been set, the process returns to step S124 to prepare for shooting of the next frame. . Thus, a series of processes relating to photographing is completed.
[0061]
<Distance and photometry processing>
FIG. 4 is a detailed flowchart of the distance measurement / photometry processing in step S122 of FIG. In the distance measurement / photometry processing, various signals are exchanged between the system control circuit 50 of the image processing apparatus 100 and the aperture control unit 340 or the distance measurement control unit 342 of the lens unit 300 through the interface 120, the connector 122, This is performed via the connector 322, the interface 320, and the lens control unit 350. The system control circuit 50 starts an AF (autofocus) process using the image sensor 14, the distance measuring means 42, and the distance measuring control means 342 (step S201).
[0062]
Next, the system control circuit 50 causes the light beam incident on the lens 310 of the lens unit 300 to pass through the stop 312, the lens mount 306, the lens mount 106 of the image processing apparatus 100, the mirror 130, and a distance measuring sub-mirror (not shown). The focus state of the image formed as an optical image is determined by making the light incident on the distance measuring means 42, and the focusing of the lens unit 300 is performed until the distance measurement (AF) is determined to be in focus (step S203). While driving the lens 310 using the distance measurement control means 342, AF control for detecting the in-focus state using the distance measurement means 42 of the image processing apparatus 100 is executed (step S202). If it is determined that the distance measurement (AF) is in focus (YES in step S203), the system control circuit 50 determines and determines the focused distance measurement point from the plurality of distance measurement points in the shooting screen. The ranging data and the setting parameters (or the ranging data or the setting parameters) are stored in the internal memory or the memory 52 of the system control circuit 50 together with the ranging point data, and the process proceeds to step S205.
[0063]
Subsequently, the system control circuit 50 starts AE (automatic exposure) processing using the photometric means 46 (step S205). The system control circuit 50 transmits the light beam incident on the lens 310 of the lens unit 300 via the stop 312, the lens mount 306, the lens mount 106 of the image processing apparatus 100, the mirrors 130 and 132, and a photometric lens (not shown). By making the light incident on the photometric unit 46, the exposure state of the image formed as an optical image is measured, and the photometric process is performed using the exposure control unit 40 until the exposure (AE) is determined to be appropriate (step S207). Perform (Step S206). If it is determined that the exposure (AE) is appropriate (YES in step S207), the system control circuit 50 stores the photometric data and the setting parameters (or the photometric data or the setting parameters) in the internal memory or the memory 52 of the system control circuit 50. It memorizes and it progresses to step S208.
[0064]
The system control circuit 50 sets the aperture value (Av value) and the shutter speed (Tv value) in accordance with the exposure (AE) result detected in the photometry processing step S206 and the shooting mode set by the mode dial switch 60. decide. Then, according to the shutter speed (Tv value) determined here, the system control circuit 50 determines the charge accumulation time of the image sensor 14, and performs the photographing process and the dark capture process with the same charge accumulation time.
[0065]
Based on the measurement data obtained in the photometric processing step S206, the system control circuit 50 determines whether or not a flash is necessary (step S208). If a flash is required, the flash flag is set and the flash 48 is charged until the charging of the flash 48 is completed (step S210) (step S209). If the charging of the flash 48 is completed (YES in step S210), the distance measurement / photometry processing routine (step S122 in FIG. 3) ends.
[0066]
<Shooting process>
5 and 6 are detailed flowcharts of the photographing process in step S128 in FIG. In the photographing process, various signals are exchanged between the system control circuit 50 of the image processing apparatus 100 and the aperture control means 340 or the distance measurement control means 342 of the lens unit 300 by the interface 120, the connector 122, the connector 322, This is performed via the interface 320 and the lens control unit 350. The system control circuit 50 moves the mirror 130 to the mirror-up position by a mirror driving unit (not shown) (step S301), and according to the photometric data stored in the internal memory or the memory 52 of the system control circuit 50, the aperture control unit 340. Then, the aperture 312 is driven to a predetermined aperture value (step S302).
[0067]
Next, after performing the charge clear operation of the image sensor 14 (step S303), the system control circuit 50 starts the charge accumulation of the image sensor 14 (step S304), and then opens the shutter 12 by the shutter control means 40 (step S304). (Step S305), exposure of the image sensor 14 is started (Step S306). Here, the system control circuit 50 determines whether or not the flash 48 is necessary based on the flash flag (step S307). If the flash 48 is required, the flash 48 emits light (step S308). Next, the system control circuit 50 waits for the end of exposure of the image sensor 14 according to the photometric data (step S309), closes the shutter 12 by the shutter control means 40 (step S310), and ends the exposure of the image sensor 14.
[0068]
Next, the system control circuit 50 drives the aperture 312 to the open aperture value by the aperture control means 340 of the lens unit 300 (step S311), and moves the mirror 130 to the mirror down position by the mirror driving means (not shown). (Step S312). If the set charge accumulation time has elapsed (YES in step S313), the system control circuit 50 reads the charge signal from the image sensor 14 after terminating the charge accumulation in the image sensor 14 (step S314), and performs A / D conversion. The photographed image data is written to a predetermined area of the memory 30 via the converter 16, the image processing circuit 20, the memory control circuit 22, or directly from the A / D converter 16 via the memory control circuit 22 (step S315). . When a series of processing is completed, the photographing processing routine (step S128 in FIG. 3) ends.
[0069]
<Correction data change processing>
FIG. 7 is a detailed flowchart of the correction data changing process in step S123 in FIG. The system control circuit 50 of the image processing apparatus 100 reads the one-dimensional correction data used for performing the horizontal dark shading correction from the non-volatile memory 56, and expands the data in the memory 30 (Step S401). Next, after performing the charge clearing operation of the image sensor 14 (step S402), the system control circuit 50 starts the charge accumulation of the image sensor 14 in the first imaging mode with the shutter 12 closed (step S403). ).
[0070]
If the set predetermined charge accumulation time has elapsed (YES in step S404), the system control circuit 50 reads the charge signal from the image sensor 14 after terminating the charge accumulation of the image sensor 14 (step S405), and Only image data of a predetermined area of the image sensor 14 is stored in the memory 30 via the / D converter 16, the image processing circuit 20, the memory control circuit 22, or directly from the A / D converter 16 via the memory control circuit 22. Write to a predetermined area (step S406). The system control circuit 50 performs horizontal dark shading correction processing on the image data written in the memory 30 using the correction data read from the nonvolatile memory 56 (step S407).
[0071]
Next, the system control circuit 50 calculates a dark level from the image data on which the horizontal dark shading correction processing has been performed (step S408). As a calculation method, for example, an average value of the image data after the horizontal dark shading correction processing is obtained and used. If the dark level obtained in step S408 is not an allowable value (“out of allowable range” in step S409), the system control circuit 50 determines that the output circuit unit (not shown) of the image sensor 14 has Since the dark level fluctuates due to the influence of the temperature, the correction data is changed so that the calculated dark level becomes an allowable value (step S410), and the correction data change processing routine ends. The change of the correction data mainly indicates a change of only the offset amount of the correction data.You.
[0072]
On the other hand, if the dark level obtained in step S408 is an allowable value (“within the allowable range” in step S409), the dark level of the image sensor 14 is adjusted to the appropriate range without being affected by the environmental temperature. Therefore, the system control circuit 50 ends the correction data change processing routine without changing the correction data.
[0073]
As described above, according to the present embodiment, the image data obtained from the first imaging mode referred to in order to change the correction data is obtained by reading data in a predetermined area instead of the entire area of the image sensor 14. Since the image data readout time is very short, even when the characteristics of the imaging system change due to the influence of the environmental temperature, it is possible to take a dark image even when the correction data is not changed. Can prevent the release time lag from increasing.
[0074]
Further, in order to change the correction data according to the image data obtained from the first imaging mode for each shooting, and to correct the image data obtained in the second imaging mode using the changed correction data, Even if the state of dark current noise of the image sensor 14 changes nonlinearly due to the temperature characteristics of the output circuit section, the noise component can be easily canceled, thereby preventing the image quality from deteriorating. A high-quality image can be obtained.
[0075]
[Other embodiments]
In the present embodiment, switching between single shooting and continuous shooting is described using single shooting / continuous shooting switch 68. However, single shooting / continuous shooting is performed according to the operation mode selection with mode dial switch 60. Of course, there is no problem even if the configuration is switched.
[0076]
Further, in the present embodiment, the charge accumulation time of the main photographing process and the charge accumulation time of the dark capture process have been described as being equal. However, the charge accumulation time is within a range where sufficient data for correcting dark current noise and the like can be obtained. If there is, there is no problem even if different charge accumulation times are used.
[0077]
Further, in the present embodiment, it has been described that the imaging operation is performed by moving the mirror 130 to the mirror up position and the mirror down position. However, the mirror 130 is configured as a half mirror, and the imaging operation is performed without moving. But of course there is no problem.
[0078]
In the present embodiment, the recording media 200 and 210 include not only a memory card such as a PCMCIA card or a compact flash (registered trademark), a hard disk, but also a micro DAT, a magneto-optical disk, a CD-R or a CD-WR. Of course, there is no problem even if it is composed of an optical disk such as an optical disk and a phase change optical disk such as a DVD.
[0079]
In the present embodiment, there is no problem even if the recording media 200 and 210 are composite media in which a memory card and a hard disk are integrated. Further, there is of course no problem if a part of the composite medium is detachable.
[0080]
In the present embodiment, the recording media 200 and 210 have been described as being separated from the image processing apparatus 100 and can be arbitrarily connected. However, any or all of the recording media are fixed to the image processing apparatus 100. Of course, there is no problem even if it remains.
[0081]
Further, in the present embodiment, the recording medium 200 or 210 can be connected to the image processing apparatus 100 singly or in an arbitrary number.
[0082]
Further, in the present embodiment, the configuration in which the recording media 200 and 210 are mounted on the image processing apparatus 100 has been described. However, the recording media may be configured by a single or a combination of a plurality of media.
[0083]
Further, in the present embodiment, the development of the horizontal dark shading correction data (step S401 in FIG. 7) has been described as being performed after the shutter switches SW1, 62 are pressed, but the horizontal dark shading correction data is developed when the power of the image processing apparatus is turned on. Of course, there is no problem even if the shading correction data is developed.
[0084]
Further, in the present embodiment, the horizontal dark shading correction data is one-dimensional in the horizontal direction. However, there is no problem if the correction data is one-dimensional or two-dimensional in the vertical direction.
[0085]
Further, in the present embodiment, the process of changing the horizontal dark shading correction data (step S123 in FIG. 3) is performed after the shutter switches SW1, 62 are pressed, but the shutter switches SW2, 64 are pressed. There is no problem even immediately before the subsequent photographing (immediately before step S129 in FIG. 3).
[0086]
Further, in the present embodiment, the process of changing the horizontal dark shading correction data (step S123 in FIG. 3) has been described as being executed irrespective of the environmental temperature. However, the process is executed only when the environmental temperature is out of the predetermined range. You may. The predetermined range refers to an environment temperature range in which the output of the image sensor 14 is not affected and the horizontal dark shading correction data does not need to be changed.
[0087]
Further, the present invention may be applied to a system including a plurality of devices or to an apparatus including a single device. A medium such as a storage medium storing software program codes for realizing the functions of the above-described embodiments is supplied to a system or an apparatus, and a computer (or CPU or MPU) of the system or apparatus stores the medium in the medium such as a storage medium. It goes without saying that the present invention can also be achieved by reading and executing the program code thus set.
[0088]
In this case, the program code itself read from a medium such as a storage medium realizes the function of the above-described embodiment, and the medium such as a storage medium storing the program code constitutes the present invention. . Examples of a medium such as a storage medium for supplying the program code include a floppy (registered trademark) disk, a hard disk, an optical disk, a magneto-optical disk, a CD-ROM, a CD-R, a magnetic tape, a nonvolatile memory card, and a ROM. Alternatively, download via a network can be used.
[0089]
When the computer executes the readout program code, not only the functions of the above-described embodiments are realized, but also the OS or the like running on the computer performs actual processing based on the instructions of the program code. It is needless to say that the present invention includes a case where the functions of the above-described embodiments are implemented by performing a part or all of the processing and performing the processing.
[0090]
Furthermore, after the program code read from a medium such as a storage medium is written to a memory provided in a function expansion board or a function expansion unit connected to the computer, based on an instruction of the program code, It is needless to say that the present invention includes a case where a CPU or the like provided in the function expansion board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.
[0091]
【The invention's effect】
As described above, according to the present invention, the image data obtained from the first imaging mode referred to in order to change the correction data is obtained by reading out only a predetermined part of the data, not the entire area of the imaging unit. Since the reading time of the image data is very short, even when the characteristic of the image pickup system changes due to the influence of the environmental temperature, the darkness can be reduced even when the correction data is not changed by the changing unit. It is possible to prevent an increase in release time lag associated with image capturing.
[0092]
Further, in order to change the correction data according to the image data obtained from the first imaging mode for each shooting, and to correct the image data obtained in the second imaging mode using the changed correction data, Even if the state of the dark current noise of the imaging means changes nonlinearly due to the temperature characteristics of the output circuit section, the noise component can be easily canceled, thereby preventing the image quality from deteriorating and improving the quality. Image can be obtained.
[Brief description of the drawings]
FIG. 1 is a block diagram illustrating a configuration of an image processing apparatus according to an embodiment of the present invention.
FIG. 2 is a flowchart of a main routine in the image processing apparatus according to the present embodiment.
FIG. 3 is a flowchart of a main routine in the image processing apparatus according to the present embodiment.
FIG. 4 is a flowchart of a distance measurement / photometry processing routine in the image processing apparatus according to the present embodiment.
FIG. 5 is a flowchart of a photographing processing routine in the image processing apparatus according to the present embodiment.
FIG. 6 is a flowchart of a photographing processing routine in the image processing apparatus according to the present embodiment.
FIG. 7 is a flowchart of a correction data change processing routine in the image processing apparatus according to the present embodiment.
[Explanation of symbols]
14 Imaging device (imaging means)
50 System control circuit (change means, correction means)
56 Non-volatile memory
100 Image processing device

Claims (6)

An image data correction device that corrects image data obtained from an imaging unit that converts an optical image into an electric signal using correction data that is an offset amount for one horizontal line stored in a memory,
Changing means for changing the correction data stored in the memory, in response to a change in image data obtained in a first imaging mode in which charge is stored without exposing the imaging means,
Correction means for correcting image data obtained in a second imaging mode in which charge accumulation is performed in a state where the imaging means is exposed, using the corrected correction data changed by the change means,
The image data correction device according to claim 1, wherein the image data obtained in the first imaging mode is noise data obtained by extracting a part of the imaging unit. 2. The apparatus according to claim 1, wherein the offset amount includes horizontal shading and a dark current noise component. The image processing apparatus characterized by comprising the image data correcting device and the imaging device of claim 1 or 2, wherein. One horizontal line for correcting image data stored in the memory corresponding to the fluctuation of the image data obtained in the first imaging mode in which the image pickup means for converting the optical image into an electric signal is stored without exposing the electric charge. Image data obtained by changing the correction data, which is the offset amount per minute, and correcting the image data obtained in the second imaging mode in which the charge is accumulated in a state where the imaging means is exposed, using the corrected correction data A correction method, wherein the image data obtained in the first imaging mode is noise data obtained by extracting a part of the imaging unit. One horizontal line for correcting image data stored in the memory corresponding to the fluctuation of the image data obtained in the first imaging mode in which the image pickup means for converting the optical image into an electric signal is stored without exposing the electric charge. Changing the correction data that is the minute offset amount, and correcting the image data obtained in the second imaging mode in which the charge is accumulated in a state where the imaging unit is exposed, using the corrected correction data. Wherein the image data obtained in the first imaging mode is noise data obtained by extracting a part of the imaging means. A storage medium storing the program according to claim 5 .

Images