JP2005208392A - Image imaging unit, image processing method and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain an accurate AF evaluation value and to reduce the cost of an imaging unit. <P>SOLUTION: When image signals from an imaging device 14 are outputted to a focusing evaluation value calculation means (50), the image signals are outputted without thinning pixel signals read from a plurality of pixels along the horizontal direction constituting the imaging device 14, meanwhile when image signals from the imaging device 14 are outputted to a signal processing means (50) for image display, the image signals are outputted by thinning the pixel signals read from the plurality of pixels along the horizontal direction constituting the imaging device 14. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to an image capturing device, an image processing method, and a program, and in particular, an image capturing unit for capturing an image of a subject, a focus evaluation value calculating unit for calculating a focus evaluation value, and a captured image on a display device. The present invention relates to an image capturing apparatus including a signal processing unit that performs signal processing for display, an image processing method applied to the image capturing apparatus, and a program for causing a computer to execute the image processing method.

  Conventionally, in a digital camera, a high frequency component of luminance is extracted from an image signal obtained from an image sensor to obtain an AF (automatic focus adjustment) evaluation value, and the focal length is adjusted so that the AF evaluation value is maximized. , Trying to get in-focus state.

  By the way, the thinning process is performed on the image signal obtained from the image sensor, and the picked-up image is displayed on the display device using the obtained signal. On the other hand, when the AF evaluation value is acquired, this thinning process is not performed. Thus, there is a conventional imaging apparatus that ensures high focusing accuracy (see, for example, Patent Document 1).

In this imaging device, an imaging element, A / D conversion means for A / D converting a pixel signal output from the imaging element, and AF that evaluates the in-focus state based on the pixel signal output from the imaging element Evaluation value calculating means; video signal processing means for performing signal processing for displaying a pixel signal output from the image sensor on a display device; and pixel signal thinning means for thinning out the output of the A / D conversion means. The output of the A / D conversion means is supplied to the AF evaluation value calculating means, and the digitized pixel signal is supplied to the video signal processing means after being thinned by the pixel signal thinning means.
JP 2003-333410 A

  However, in the above conventional imaging device, in both cases, the pixel signal is supplied to the AF evaluation value calculating means, and the pixel signal is supplied to the video signal processing means via the pixel signal thinning means. Pixel signals are read out from the element in the same drive mode.

  For this reason, the conventional imaging apparatus has problems that an accurate AF evaluation value cannot be obtained, the amount of signal processing data is enormous, processing is slow, and a circuit cost for thinning out is high. .

  The present invention has been made in view of such problems, and provides an image pickup apparatus, an image processing method, and a program that can acquire an accurate AF evaluation value and reduce the cost of the device. With the goal.

  In order to achieve the above object, according to the first aspect of the present invention, an image pickup means for picking up a subject, and each pixel read from a plurality of pixels in the horizontal direction when an image signal is read from the image pickup means. First image signal output means for performing signal thinning and outputting the image signal, and when reading the image signal from the imaging means, without performing thinning of each pixel signal read from a plurality of pixels in the horizontal direction Second image signal output means for outputting the image signal; focus evaluation value calculation means for calculating a focus evaluation value; signal processing means for performing signal processing for displaying a captured image on a display device; When outputting an image signal from the imaging unit to the focus evaluation value calculating unit, the second image signal output unit is operated, and the image signal is output from the imaging unit to the signal processing unit. The image capturing apparatus is provided, characterized in that a control means for operating said first image signal output means.

  According to the fifth aspect of the present invention, the image pickup means for picking up the subject, the focus evaluation value calculation means for calculating the focus evaluation value, and the signal processing for displaying the picked-up image on the display device In the image processing method applied to the image pickup apparatus including the signal processing means for performing the image processing, when the image signal is output from the image pickup means to the focus evaluation value calculation means, the horizontal direction constituting the image pickup means A first image signal output step of outputting the image signal without thinning out each pixel signal read from the plurality of pixels, and when outputting the image signal from the imaging unit to the signal processing unit, And a second image signal output step of outputting the image signal by thinning out each pixel signal read from a plurality of horizontal pixels constituting the image pickup means. Management method is provided.

  Furthermore, a program for causing a computer to execute the image processing method is provided.

  According to the present invention, when the image signal is output from the imaging unit to the focus evaluation value calculating unit, the image signal is not thinned out from each pixel signal read from the plurality of horizontal pixels constituting the imaging unit. On the other hand, when the image signal is output from the image pickup means to the signal processing means for image display, each pixel signal read out from a plurality of pixels in the horizontal direction constituting the image pickup means is thinned to obtain the image signal. Is output.

  As a result, accurate AF evaluation values can be obtained, and pixel signal decimation means provided in front of the video signal processing means as in a conventional imaging apparatus is not required, which enables downsizing and cost reduction of equipment. Become.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a block diagram showing a configuration of an image processing apparatus according to an embodiment of the present invention. This image processing apparatus is an image capturing apparatus that records a still image and / or a moving image on a recording medium.

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

  10 is a photographing lens, 12 is a shutter having a diaphragm function, 14 is an image sensor that converts an optical image into an electric signal, and 16 is an A / D converter that converts an analog signal output of the image sensor 14 into a digital signal. is there.

  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. The image processing circuit 20 performs predetermined calculation processing using image data obtained by imaging, and the system control circuit 50 performs exposure control unit 40, distance measurement control based on the obtained calculation result. Control is performed on the unit 42, whereby TTL (through-the-lens) AF (automatic focus adjustment) processing, AE (automatic exposure adjustment) processing, and EF (flash pre-emission) processing are performed. Further, the image processing circuit 20 performs predetermined arithmetic processing using image data obtained by imaging, 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.

  Data of the A / D converter 16 is written into the image display memory 24 or the memory 30 through the image processing circuit 20, the memory control circuit 22, or only through the memory control circuit 22.

  Reference numeral 24 denotes an image display memory, 26 denotes a D / A converter, 28 denotes an image display unit including a TFT, an LCD, and the like. The display image data written in the image display memory 24 is converted to a D / A converter 26. And sent to the image display unit 28 for display.

  An electronic viewfinder function can be realized by sequentially displaying image data obtained by imaging using the image display unit 28. The image display unit 28 can 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. .

  Reference numeral 30 denotes a memory for storing still images and moving images obtained by photographing, and has a storage capacity sufficient to store a predetermined number of still images and moving images for a predetermined time. Thereby, even in the case of continuous shooting or panoramic shooting in which a plurality of still images are continuously shot, a large amount of image writing can be performed to the memory 30 at high speed. The memory 30 can also be used as a work area for the system control circuit 50.

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

  Reference numeral 40 denotes an exposure control unit that controls the shutter 12 having a diaphragm function, and also has a flash light control function realized in cooperation with the flash 48.

  Reference numeral 42 denotes a distance measurement control unit that controls focusing of the photographing lens 10, 44 denotes a zoom control unit that controls zooming of the photographing lens 10, and 46 denotes an operation of the protection unit 102 that is a barrier for protecting the photographing lens 10. It is a barrier control part which controls.

  A flash 48 has an AF auxiliary light projecting function and a flash light control function.

  The exposure control unit 40 and the distance measurement control unit 42 are controlled using the TTL method, and the system control circuit 50 performs exposure based on the calculation result obtained by calculating the image data obtained by imaging by the image processing circuit 20. Control is performed on the control unit 40 and the distance measurement control unit 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 in the system control circuit 50.

  Reference numeral 54 denotes a display unit that displays an operation state, a message, and the like using characters, images, sounds, and the like according to execution of a program in the system control circuit 50. The display unit 54 easily recognizes the vicinity of the operation unit of the image processing apparatus 100. One or a plurality of positions are installed at the position, and are configured by a combination of, for example, an LCD, an LED, and a sounding element. The display unit 54 is partly 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, recording pixel number display, recording number display, remaining image number display, shutter Speed display, Aperture value display, Exposure compensation display, Flash display, Red-eye reduction display, Macro shooting display, Buzzer setting display, Clock battery level display, Battery level display, Error display, Multi-digit number information display and recording There are a display state of the medium 200 and the recording medium 210, a communication I / F operation display, a date / time display, and the like.

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

  Reference numeral 56 denotes an electrically erasable / recordable non-volatile memory, such as an EEPROM.

  Reference numerals 60, 62, 64, 66, 68 and 70 are operation means for inputting various operation instructions to the system control circuit 50, such as switches, dials, touch panels, pointing by line-of-sight detection, voice recognition devices, and the like. Consists of one or more 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 while a shutter button (not shown) is being operated (half-pressed), and instructs to start processing such as AF processing, AE processing, AWB processing, and EF processing.

  A shutter switch SW2 64 is turned on when a shutter button (not shown) is completed (fully pressed), and the 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 written as data, development processing using computations in the image processing circuit 20 and the memory control circuit 22, image data is read out from the memory 30, compressed by the compression / decompression circuit 32, and stored in the recording medium 200 or the recording medium 210. An instruction to start the operation of a series of processing called recording processing to be written is given.

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

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

  Reference numeral 70 denotes an operation unit including various buttons, a touch panel, and the like. Menu button, set button, macro button, multi-screen playback page break button, flash setting button, single shooting / continuous shooting / self-timer switching button, menu movement + ( A plus button, a menu movement- (minus) button, a reproduction image movement + (plus) button, a reproduction image- (minus) button, a shooting image quality selection button, an exposure correction button, a date / time setting button, and the like.

  Reference numeral 80 denotes a power supply control unit, which includes a battery detection circuit, a DC-DC converter, a switch circuit that switches blocks to be energized, and the like. The presence / absence of the battery, the type of battery, and the remaining battery level are detected, and the DC-DC converter is controlled based on the detection result and the instruction of the system control circuit 50. Supplied to each part including 210.

  Reference numeral 82 denotes a connector, 84 denotes a connector, and 86 denotes a power supply unit including a primary battery such as an alkaline battery or a lithium battery, a secondary battery such as a NiCd battery, NiMH battery, or Li battery, an AC adapter, or the like.

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

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

  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, or the like. By connecting various types of communication cards such as cards, P1284 cards, SCSI cards, PHS and other communication cards, image data and management information attached to image data can be transferred to and from peripheral devices such as other computers and printers. Can fit.

  Reference numeral 102 denotes a protective unit that covers the imaging unit including the lens 10 of the image processing apparatus 100 to prevent the imaging unit from being dirty or damaged.

  Reference numeral 104 denotes an optical viewfinder, which can take an image using only the optical viewfinder without using the electronic viewfinder function of the image display unit 28. In addition, some functions of the display unit 54 are provided in the optical viewfinder 104, for example, display functions such as in-focus display, camera shake warning display, flash charge display, shutter speed display, aperture value display, and exposure correction display. ing.

  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 composed of a memory card, a hard disk, or the like.

  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 composed of a memory card, a hard disk, or the like.

  The recording medium 210 includes a recording unit 212 composed of a semiconductor memory, a magnetic disk, and 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 having such a configuration will be described below.

  2 to 5 are flowcharts of a main routine showing the operation of the image processing apparatus 100. This main routine is started by turning on the power after battery replacement or the like.

  When the main routine is started, the system control circuit 50 initializes flags, control variables, and the like (S101), and initializes the image display of the image display unit 28 to the OFF state (S102).

  In step S103, the system control circuit 50 recognizes the setting position of the mode dial 60. If the mode dial 60 is set to power OFF, the system control circuit 50 proceeds to step S105 and changes the display on each display unit to the end state. , The barrier of the protection unit 102 is closed to protect the imaging unit, and necessary parameters, setting values, and setting modes including flags and control variables are recorded in the nonvolatile memory 56, and the image display unit is And a predetermined end process such as shutting off an unnecessary power source of each unit of the image processing apparatus 100 including the H.28. Thereafter, the process returns to step S103.

  If the mode dial 60 is set to the shooting mode in step S103, the process proceeds to step S106. If the mode dial 60 is set to another mode, the process proceeds to step S104, and the system control circuit 50 executes a process according to the selected mode. If the process is completed, the process proceeds to step S103. Return.

  In step S <b> 106, whether or not the system control circuit 50 is in a situation in which the remaining capacity or the operation status of the power supply unit 86 made of a battery or the like adversely affects the normal operation of the image processing apparatus 100 via the power supply control unit 80. If the condition is negatively affected (NO in S106), a predetermined warning is displayed using an image or sound using the display unit 54 (S108), and the process returns to step S103.

  On the other hand, if there is no problem in the power supply unit 86 (YES in S106), the system control circuit 50 determines that the operation state of the recording medium 200 or the recording medium 210 is the operation of the image processing apparatus 100, particularly the recording of image data on the recording medium. It is determined whether or not the playback operation is disturbed (S107). As a result, if it is in a state of giving a trouble, the process proceeds to step S108, a predetermined warning is displayed by an image or sound using the display unit 54 (S108), and the process returns to step S103.

  On the other hand, if there is no trouble, the display unit 54 is used to display various setting states of the image processing apparatus 100 using images and sounds (S109). If the image display of the image display unit 28 is ON, the image display unit 28 is also used to display various setting states of the image processing apparatus 100 using images and sounds.

  Next, in step S110 of FIG. 3, the system control circuit 50 checks the setting state of the quick review ON / OFF switch 68, and if it is set to quick review ON, sets the quick review flag (S111). If the quick review is set to OFF, the quick review flag is canceled (S112). The state of the quick review flag is stored in the internal memory or the memory 52 of the system control circuit 50.

  Subsequently, the system control circuit 50 checks the setting state of the image display ON / OFF switch 66 (S113). If the image display ON is set, the system control circuit 50 sets the image display flag (S114) and the image display unit. The image display of 28 is set to the ON state (S115), the image data obtained by imaging is set to the through display state for sequentially displaying (S116), and the process proceeds to step S119 in FIG.

  In the through display state, the data sequentially written in the image display memory 24 via the image sensor 12, the A / D converter 16, the image processing circuit 20, and the memory control circuit 22 are stored in the memory control circuit 22, D The data is sent to the image display unit 28 via the / A converter 26 and sequentially displayed, whereby the image display unit 28 realizes an electronic finder function.

  If the image display ON / OFF switch 66 is set to OFF in step S113, the image display flag is canceled (S117), and the image display on the image display unit 28 is set to the OFF state (S118). The process proceeds to step S119 in FIG.

  When the image display is OFF, the user does not use the electronic viewfinder function of the image display unit 28 but performs shooting using the optical viewfinder 104. In this case, it is possible to reduce power consumption of the image display unit 28, the D / A converter 26, and the like that consume a large amount of power. The state of the image display flag is stored in the internal memory or the memory 52 of the system control circuit 50.

  In step S119 of FIG. 4, the system control circuit 50 recognizes the operation state of the shutter switch (SW1) 62 and returns to step S103 if it is OFF. On the other hand, if it is ON, the system control circuit 50 recognizes the state of the image display flag stored in the internal memory of the system control circuit 50 or the memory 52 (S120), and if the image display flag is set (S120). The display state of the image display unit 28 is set to the freeze display state (S121), and the process proceeds to step S122. On the other hand, if the image display flag has been canceled (OFF in S120), the process proceeds to step S122.

  In the freeze display state, rewriting of the image data in the image display memory 24 via the image sensor 12, the A / D converter 16, the image processing circuit 20, and the memory control circuit 22 is prohibited, and the last written image data Is sent to and displayed on the image display unit 28 via the memory control circuit 22 and the D / A converter 26, thereby displaying the frozen video on the electronic viewfinder.

  In the next step S122, the system control circuit 50 performs a distance measurement process to focus the photographing lens 10 on the subject, performs a photometry process, and determines an aperture value E and a shutter time. In the photometric process, the flash is set if necessary.

  The distance measurement / photometry processing in step S122 will be described in detail later with reference to FIG.

  When step S122 of the distance measurement / photometry process is completed, the system control circuit 50 recognizes the state of the image display flag stored in the internal memory of the system control circuit 50 or the memory 52 (S123), and the image display flag is set. If it has been set (ON in S123), the display state of the image display unit 28 is set to the through display state (S124), and the process proceeds to step S125. If the image display flag has been canceled (OFF in S123), step S124 is skipped and the process proceeds to step S125. Note that the through display in step S124 is the same operation as the through display in step S116.

  In the next step S125, the system control circuit 50 recognizes the operation state of the shutter switch (SW2) 64. If it is OFF, the process proceeds to step S126, and if it is ON, the process proceeds to step S127. In step S126, the system control circuit 50 recognizes the operation state of the shutter switch (SW1) 62, and returns to step S103 if it is OFF, and returns to step S125 if it is ON.

  In step S127, the system control circuit 50 recognizes the state of the image display flag stored in the internal memory of the system control circuit 50 or the memory 52, and if the image display flag is set (ON in S127), The display state of the image display unit 28 is set to the fixed color display state (S128), and the process proceeds to step S129. If the image display flag has been canceled (OFF in S127), step S128 is skipped and the process proceeds to step S129.

  In the fixed color display state, instead of the captured image data written in the image display memory 24 via the image sensor 12, the A / D converter 16, the image processing circuit 20, and the memory control circuit 22, it is replaced. The fixed color image data is sent to and displayed on the image display unit 28 via the memory control circuit 22 and the D / A converter 26, whereby the fixed color image is displayed on the electronic viewfinder.

  In step S129, the system control circuit 50 transfers the image sensor 12 to the memory 30 via the A / D converter 16, the image processing circuit 20, and the memory control circuit 22, or the A / D converter 16 and the memory control circuit. The image data written in the memory 30 is read out and subjected to various processes using the exposure processing for writing the captured image data into the memory 30 via the memory 22 and the memory control circuit 22 and, if necessary, the image processing circuit 20. A photographing process including a developing process is executed.

  The photographing process in step S129 will be described later in detail with reference to FIG.

  Next, in step S130 of FIG. 5, if the system control circuit 50 recognizes the state of the image display flag stored in the internal memory of the system control circuit 50 or the memory 52 and the image display flag is set ( The quick review display is performed (S133). In this case, the image display unit 28 is always displayed as an electronic viewfinder even during shooting, and quick review display immediately after shooting is also performed.

  If the image display flag has been canceled (OFF at S130), the state of the quick review flag stored in the internal memory of the system control circuit 50 or the memory 52 is recognized (S131), and the quick review flag is set. If it is (ON in S131), the image display of the image display unit 28 is set to the ON state (S132), and quick review display is performed (S133). If the quick review flag has been canceled (OFF in S131), the process proceeds to step S134.

  As described above, according to the present embodiment, the image display of the image display unit 28 is set to OFF without using the electronic finder function in order to save power or to perform shooting using the optical finder 104. However, if the quick review function is set by the quick review ON / OFF switch 68, it is possible to automatically reproduce the captured image on the image display unit 28 immediately after shooting, and to save power. It is possible to provide a convenient function that is compatible with confirmation of a captured image.

  If the image display flag is released (OFF in S130) and the quick review flag is also released (0FF in S131), the process proceeds to step S134 while the image display unit 28 remains OFF. In this case, the image display unit 28 remains off immediately after shooting and no quick review display is performed. This is because there is no need to check the photographed image immediately after photographing as in the case of continuing photographing using the optical finder 104, and power saving is emphasized without using the electronic finder function of the image display unit 28. How to use.

  In step S134, the system control circuit 50 reads the captured image data written in the memory 30, performs various image processing using the memory control circuit 22 and, if necessary, the image processing circuit 20, and performs compression / decompression. After performing the image compression process according to the mode set using the circuit 32, the recording process for writing the image data to the recording medium 200 or the recording medium 210 is executed.

  The recording process in step S134 will be described in detail later with reference to FIG.

  After the recording process in step S134 is completed, in step S135, the system control circuit 50 recognizes the operating state of the shutter switch (SW2) 64. If the shutter switch (SW2) 64 is in the ON state, the system control circuit 50 proceeds to step S136. The state of the continuous shooting flag stored in the internal memory or the memory 52 is recognized. As a result, if the continuous shooting flag is set (ON in S136), the process returns to step S129 to perform continuous shooting, and the next shooting is performed. On the other hand, if the continuous shooting flag is not set (OFF in S136), the process returns to step S135, and the processes in steps S135 and S136 are repeated until the shutter switch (SW2) 64 is turned off.

  Thus, according to the present embodiment, in the operation setting state in which the quick review display is performed immediately after shooting, if the shutter switch SW2 is in the ON state when step S134 for performing the recording process is completed, The quick review display on the image display unit 28 is continued until the shutter switch SW2 is turned OFF, thereby making it possible to carefully check the captured image.

  If the shutter switch SW2 is in the OFF state when step S134 of the recording process is completed (OFF in S135), or the shutter switch SW2 is in the ON state and the quick review display is continuously performed and the captured image is displayed. If the shutter switch SW2 is turned off after confirming (OFF in S135), the process waits for the elapse of a predetermined minimum review time (S137), and proceeds to step S138.

  Thus, according to the present embodiment, the quick review display on the image display unit 28 is continued for at least a predetermined minimum review time. As a result, it is possible to surely check the photographed image, stop the quick review display by executing steps S139 and S140 described later, and continue the quick review display unnecessarily for a long time. It is possible to prevent losing the next shooting opportunity.

  The minimum review time may be a fixed value, may be arbitrarily set by the user, or may be arbitrarily set or selected by the user within a predetermined range.

  Next, in step S138, the system control circuit 50 determines whether the image display flag is set. If the image display flag is set (ON in S138), the display state of the image display unit 28 is passed through. The display state is set (S139), and the process proceeds to step S141.

  In this case, after confirming the captured image by the quick review display on the image display unit 28, it is possible to enter a through display state in which image data captured for the next imaging is sequentially displayed.

  If the image display flag has been canceled (OFF in S138), the image display of the image display unit 28 is set to the OFF state (S140), and the process proceeds to step S141.

  In this case, after confirming the photographed image by the quick review display on the image display unit 28, the function of the image display unit 28 is stopped for power saving, and the image display unit 28 or D / A conversion with large power consumption is stopped. It is possible to reduce the power consumption of the device 26 and the like.

  In step S141, the system control circuit 50 recognizes the operation state of the shutter switch (SW1) 62, and if it is in the ON state, returns to step S125 to prepare for the next shooting. On the other hand, if it is in the OFF state, the system control circuit 50 ends the series of shooting operations and returns to step S103.

  FIG. 6 is a flowchart showing a detailed procedure of the distance measurement / photometry process in step S122 of FIG.

  The system control circuit 50 reads the charge signal from the image sensor 14 and sequentially reads the captured image data into the image processing circuit 20 via the A / D converter 16 (S201). Using the sequentially read image data, the image processing circuit 20 is used for TTL (through the lens) type AE (automatic exposure) processing, EF (flash pre-flash) processing, and AF (autofocus) processing. Perform a predetermined calculation.

  It should be noted that in each process here, a specific portion of the photographed screen is cut out and extracted as necessary, and an operation is performed on the charge signals of the pixels constituting them. As a result, in each of the TTL method AE, EF, AWB, and AF processes, it is possible to perform an optimal calculation for each different mode such as the center weight mode, the average mode, and the evaluation mode.

  In step S202, the system control circuit 50 determines whether the exposure (AE) is appropriate using the calculation result in the image processing circuit 20. If not appropriate (NO in S202), AE control is performed using the exposure control unit 40 (S203). Then, the process proceeds to step 204.

  In step S204, using the measurement data obtained by AE control, the system control circuit 50 determines whether flash (flash) is necessary. If flash is necessary (YES in S204), the flash flag is set. The flash 48 is charged by setting (S205). On the other hand, if the flash is unnecessary (NO in S204), the process returns to step S201.

  If it is determined in step S202 that the exposure (AE) is appropriate (YES in S202), the measurement data and / or setting parameters are stored in the internal memory of the system control circuit 50 or the memory 52, and the process proceeds to step S206. Thus, the system control circuit 50 determines whether or not the white balance (AWB) is appropriate using the calculation result in the image processing circuit 20 and the measurement data obtained by the AE control. As a result, if it is not appropriate (NO in S206), the process proceeds to step S207, and the color processing parameters are adjusted using the image processing circuit 20 to perform AWB control. Then, the process returns to step S201.

  On the other hand, if it is determined that the white balance (AWB) is appropriate (YES in S206), the measurement data and / or setting parameters are stored in the internal memory of the system control circuit 50 or the memory 52, and the process proceeds to step S208.

  In step S208, using the measurement data obtained by the AE control and the AWB control, the system control circuit 50 determines whether or not the distance measurement (AF) is in focus. As a result, if it is not in focus (NO in S208), the process proceeds to step S209, and AF control is performed using the distance measurement control unit. Then, the process returns to step S201. In the AF control in step S208, the driving mode of the image sensor 14 is set to a mode without horizontal thinning, which will be described later with reference to FIG.

  On the other hand, if ranging (AF) is determined to be in focus (YES in S208), the measurement data and / or setting parameters are stored in the internal memory of the system control circuit 50 or the memory 52, and ranging / photometric processing is performed. When finished, the process proceeds to step 123 in FIG.

  FIG. 7 is a flowchart showing a detailed procedure of the photographing process in step S129 of FIG.

  In accordance with the photometric data stored in the internal memory of the system control circuit 50 or the memory 52, the system control circuit 50 opens the shutter 12 having the aperture function by an amount corresponding to the aperture value by the exposure control unit 40 (S301). Exposure of the image sensor 10 is started (S302).

  It is determined whether or not the flash 48 is necessary based on the flash flag (S303). If necessary, the flash is emitted (S304). If unnecessary (NO in S303), step S304 is skipped.

  The system control circuit 50 waits for the end of exposure of the image sensor 12 according to the photometric data (S305). When the exposure ends (YES in S305), the shutter 12 is closed (S306), the charge signal is read from the image sensor 14, and A / D The captured image data is written in the memory 30 through the converter 16, the image processing circuit 20, and the memory control circuit 22, or through the A / D converter 16 and the memory control circuit 22 (S307).

  It is determined whether or not it is necessary to perform frame processing according to the set shooting mode (S308), and if necessary (YES in S308), the system control circuit 50 performs the memory control circuit 22 and the necessity. Accordingly, the image processing circuit 20 is used to sequentially read out the image data written in the memory 30 and perform vertical addition processing (S309) and color processing (S310). Then, the processed image data is written into the memory 30. On the other hand, if it is not necessary to perform frame processing (NO in S308), steps S309 and S310 are skipped.

  Thereafter, the system control circuit 50 reads the image data from the memory 30 and transfers the display image data to the image display memory 24 via the memory control circuit 22 (S311).

  When a series of photographing processes is completed, the process proceeds to step S130 in FIG.

  FIG. 8 is a flowchart showing a detailed procedure of the recording process in step S134 of FIG.

  The system control circuit 50 reads out the captured image data written in the memory 30 using the memory control circuit 22 and, if necessary, the image processing circuit 20 and interpolates the vertical / horizontal pixel ratio of the image sensor 14 to 1: 1. A square process is performed (S401), and the processed image data is written in the memory 30.

  Then, the image data written in the memory 30 is read out, and the image compression processing corresponding to the set mode is performed by the compression / decompression circuit 32 (S402), and then via the interface 90 or the interface 94, the connector 92 or the connector 96. Then, the compressed image data is written to the recording medium 200 or the recording medium 210 such as a memory card or a compact flash (registered trademark) card (S403).

  When the writing to the recording medium 200 or the recording medium 210 is completed, the process proceeds to step S135 in FIG.

  Next, the drive mode of the image sensor 14 when the shutter switch (SW1) 62 is ON will be described with reference to FIG.

  FIG. 9 is a timing chart showing the drive mode of the image sensor 14 when the shutter switch (SW1) 62 is ON.

  9A shows a vertical synchronization signal (VD) applied to the image sensor 14, FIG. 9B shows an operation state (camera status) of the image processing apparatus 100, and FIG. 9C shows an image sensor. 14 (CCD) drive mode, and (D) shows the display state of the image display unit 28.

  In the present embodiment, there are three drive modes as a method for reading out a charge signal from the two-dimensional imaging device 14. The first drive mode thins out horizontal lines in the vertical direction and is adjacent in the horizontal lines. This is a method of thinning out pixels in the horizontal direction by adding the charge signals of a plurality of pixels, and the second driving mode is a method of thinning out horizontal lines in the vertical direction and not thinning out pixels in the horizontal direction. The third drive mode is a method of reading out charge signals from all pixels without thinning out horizontal lines in the vertical direction or thinning out pixels in the horizontal direction. The third drive mode is a drive mode selected in the photographing process when the shutter switch (SW2) 64 is ON.

  A charge signal (image signal) for one frame is read from the image sensor 14 in synchronization with the vertical synchronization signal (VD).

  Before the shutter switch (SW1) 62 is turned on, the operation state (camera status) of the image processing apparatus 100 is in the normal finder state (EVF: B1), and the image display unit 28 in which the image display is set to ON is through. In the display state (see step S116 in FIG. 3), a live image is displayed on the image display unit 28 (D1). At this time, the image sensor 14 operates in the first drive mode (horizontal thinning mode: C1).

  When the shutter switch (SW1) 62 is turned on, photometric processing (AE before AE: B2) before AF processing is performed. At this time, the image sensor 14 continues to operate in the first drive mode (horizontal thinning mode: C2). Then, exposure control (AE) is performed based on the photometric data (see step S203 in FIG. 6).

  When the exposure control is completed, in order to acquire an AF evaluation value (B3), the image sensor 14 is driven in the second drive mode (non-thinning mode: C3). At that time, displaying the image change accompanying the change of the drive mode on the image display unit 28 impairs the image quality of the image processing apparatus 100, so that the display image of the image processing apparatus 100 is frozen (D2, FIG. 4 step S121).

  During acquisition of the AF evaluation value (B3), the image sensor 14 is driven in the second drive mode (non-decimation mode: C3), and when acquisition of the AF evaluation value is completed (B4), the image sensor 14 is moved to the first mode. Return to the operation state of the drive mode (horizontal thinning mode: C4). Then, the freeze display of the image processing apparatus 100 is canceled, and the image display unit 28 is set to the through display state (D3, see step S124 in FIG. 4).

  As described above, by changing the driving mode of the image sensor 14, an accurate AF evaluation value can be obtained, and a pixel signal thinning unit provided in front of the video signal processing unit as in the conventional imaging device. This eliminates the need to reduce the size and cost of the device.

  In the above embodiment, the image sensor 14 is uniformly driven in the first drive mode (horizontal thinning mode: C2) during the photometric process (B2 in FIG. 9B). When the subject image is dark, the image sensor 14 is driven in the first drive mode (horizontal thinning mode). On the other hand, when the subject image is bright, the image sensor 14 is driven in the second drive mode (no thinning). Mode), thereby improving the photometric accuracy.

[Other Embodiments]
An object of the present invention is to supply a storage medium storing software program codes for realizing the functions of the above-described embodiments to a system or apparatus, and a computer (or CPU, MPU, etc.) of the system or apparatus. It is also achieved by reading and executing the program code stored in the storage medium.

  In this case, the program code itself read from the storage medium realizes the novel function of the present invention, and the storage medium and program storing the program code constitute the present invention.

  The storage medium for supplying the program code is, for example, a flexible disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD-R, CD-RW, DVD-ROM, DVD-RAM, DVD-RW. DVD + RW, magnetic tape, nonvolatile memory card, ROM, etc. can be used.

  Further, by executing the program code read by the computer, not only the functions of the above-described embodiments are realized, but also an OS (operating system) or the like running on the computer based on the instruction of the program code. Includes a case where part or all of the actual processing is performed and the functions of the above-described embodiments are realized by the processing.

  Further, after the program code read from the storage medium is written in a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, the function expansion is performed based on the instruction of the program code. This includes the case where the CPU or the like provided in the board or the function expansion unit performs part or all of the actual processing and the functions of the above-described embodiments are realized by the processing.

1 is a block diagram illustrating a configuration of an image processing apparatus according to an embodiment of the present invention. It is a flowchart (1/4) of the main routine which shows operation | movement of an image processing apparatus. It is a flowchart (2/4) of the main routine which shows operation | movement of an image processing apparatus. It is a flowchart (3/4) of the main routine which shows operation | movement of an image processing apparatus. It is a flowchart (4/4) of the main routine which shows operation | movement of an image processing apparatus. It is a flowchart which shows the detailed procedure of the ranging / photometry process in step S122 of FIG. It is a flowchart which shows the detailed procedure of the imaging | photography process in step S129 of FIG. It is a flowchart which shows the detailed procedure of the recording process in step S134 of FIG. 6 is a timing chart illustrating a driving mode of the image sensor when the shutter switch SW1 is ON.

Explanation of symbols

10: Shooting lens 12: Shutter 14: Image sensor (imaging means)
16: A / D converter 18: Timing generation circuit 20: Image processing circuit 22: Memory control circuit 24: Image display memory 26: D / A converter 28: Image display unit (display device)
30: Memory 32: Image compression / decompression circuit 40: Exposure control unit 42: Distance measurement control unit 44: Zoom control unit 46: Barrier control unit 48: Flash 50: System control circuit (first and second image signal output means) , Focus evaluation value calculation means, signal processing means, control means)
52: Memory 54: Display unit 56: Non-volatile memory 60: Mode dial switch 62: Shutter switch SW1
64: Shutter switch SW2
66: Image display ON / OFF switch 68: Quick review ON / OFF switch 70: Operation unit 80: Power supply control unit 82: Connector 84: Connector 86: Power supply means 90: Interface 92: Connector 94: Interface 96: Connector 98: Recording Medium attachment / detachment detection unit 100: Image processing apparatus (image capturing apparatus)
102: Protection unit 104: Optical finder 110: Communication unit 112: Connector (or antenna)
200: Recording medium 202: Recording unit 204: Interface 206: Connector 210: Recording medium 212: Recording unit 214: Interface 216: Connector

Claims (9)

Imaging means for imaging a subject;
A first image signal output means for outputting the image signal by thinning out each pixel signal read from a plurality of pixels in the horizontal direction when reading the image signal from the imaging means;
Second image signal output means for outputting the image signal without thinning out each pixel signal read from a plurality of pixels in the horizontal direction when reading the image signal from the imaging means;
A focus evaluation value calculating means for calculating a focus evaluation value;
Signal processing means for performing signal processing for displaying a captured image on a display device;
When outputting an image signal from the imaging means to the focus evaluation value calculating means, operating the second image signal output means, and outputting an image signal from the imaging means to the signal processing means And an image pickup apparatus comprising: control means for operating the first image signal output means.   2. The image according to claim 1, wherein the first image signal output unit performs addition of pixel signals read from a plurality of adjacent pixels among a plurality of horizontal pixels constituting the imaging unit. Imaging device.   The control means operates the first image signal output means when the subject brightness is lower than a predetermined value when the image signal is output from the imaging means to the signal processing means, while the subject brightness is 3. The image pickup apparatus according to claim 2, wherein the second image signal output means is operated if it is equal to or greater than a predetermined value. At least during the operation of the focus evaluation value calculation means, the image display control means for causing the display device to display an image displayed on the display device before the operation of the focus evaluation value calculation means. The image pickup apparatus according to claim 1, characterized in that: An image pickup apparatus comprising: an image pickup means for picking up a subject; a focus evaluation value calculation means for calculating a focus evaluation value; and a signal processing means for performing signal processing for displaying the picked-up image on a display device In the image processing method applied to
When outputting an image signal from the imaging unit to the focus evaluation value calculating unit, the image signal is output without thinning out each pixel signal read from a plurality of horizontal pixels constituting the imaging unit. A first image signal output step,
When outputting an image signal from the image pickup means to the signal processing means, a second thinning out each pixel signal read from a plurality of horizontal pixels constituting the image pickup means and outputting the image signal An image processing method comprising: an image signal output step.   6. The image according to claim 5, wherein the second image signal output step performs addition of pixel signals read from a plurality of adjacent pixels among a plurality of pixels in the horizontal direction constituting the imaging unit. Processing method.   In the second image signal output step, when the image signal is output from the imaging unit to the signal processing unit, if the subject brightness is lower than a predetermined value, the image signal is output by performing the thinning. 7. The image processing method according to claim 6, wherein if the subject brightness is equal to or greater than the predetermined value, the image signal is output without performing the thinning. At least during the operation of the focus evaluation value calculation means, the image display control step of causing the display device to display an image displayed on the display device before the operation of the focus evaluation value calculation means. The image processing method according to claim 5, wherein: An image pickup apparatus comprising: an image pickup means for picking up a subject; a focus evaluation value calculation means for calculating a focus evaluation value; and a signal processing means for performing signal processing for displaying the picked-up image on a display device In a program for causing a computer to execute an image processing method applied to
When outputting an image signal from the imaging unit to the focus evaluation value calculating unit, the image signal is output without thinning out each pixel signal read from a plurality of horizontal pixels constituting the imaging unit. A first image signal output step,
When outputting an image signal from the image pickup means to the signal processing means, a second thinning out each pixel signal read from a plurality of horizontal pixels constituting the image pickup means and outputting the image signal An image signal output step.

Images