JP4710351B2 - Digital camera and program - Google Patents

Description

  The present invention relates to a digital camera including a plurality of image sensors and a program.

There is a digital camera provided with two image sensors (see, for example, Patent Document 1). The technique disclosed in Patent Document 1 includes image sensors on the front and rear surfaces of a digital camera, and synthesizes an image captured by the front image sensor and an image captured by the rear image sensor.
On the other hand, since a digital camera uses a monitor such as a liquid crystal as a finder, it is difficult to check camera shake. In view of this, there is a digital camera that makes it easy to check the camera shake state by displaying an enlarged image of the subject on a part of the monitor (see, for example, Patent Documents 2 and 3).
Furthermore, there is a device that includes a plurality of image sensors and that captures a subject image with one image sensor and detects the state of incident light with another image sensor (see, for example, Patent Document 4).

JP 2004-363994 A JP-A-11-331649 JP 2001-28699 A JP-A-8-79597

  In the technique described in Patent Document 1, a first image sensor is provided on the front surface of the camera and a second image sensor is provided on the rear surface, and both images can be combined, but there are so many opportunities to take composite photographs. However, there is a problem that the other image sensor is not normally used.

  Further, in the technique described in Patent Document 2, when an LCD monitor is used as a finder, an image pickup apparatus that allows a photographer to confirm a focus state reliably by performing an enlargement process on all or a part of the LCD monitor and displaying it. Although provided, since there is only one image pickup device, an image to be photographed and an enlarged display image have to be performed in parallel by electronic processing, and there is a problem that processing speed is reduced.

  In the technique described in Patent Document 3, the display area of the display device with respect to the specific area is enlarged, and the focus of the subject is confirmed before shooting. In addition, as in Patent Document 2, since there is only one imaging device, an image to be captured and an image for enlargement display are processed in parallel by electronic processing. Therefore, there is a problem that the processing speed decreases.

  In the technique described in Patent Document 4, a plurality of image sensors are provided, a subject image is generated based on a signal output from at least one image sensor, and substantially the same as the image sensor for generating the subject image. By detecting the state of incident light based on the signal of another imaging element having a shooting area, it is possible to simultaneously perform imaging of the subject image and detection of the state of incident light. Since a plurality of image sensors are incident on the same shooting region, there is a problem that the light state of the subject can be understood but the surrounding light source information such as the light source behind the photographer is not known.

  The present invention has been made to solve the above-described problems of the prior art, and includes an imaging apparatus, a digital camera, a program, and a process that include a plurality of imaging elements and can obtain more reliable ambient light source information. It is an object of the present invention to provide a digital camera and a program that can display a blur confirmation image without slowing down the speed.

In order to solve the above-described problem, in the first aspect of the present invention, the first imaging unit that captures the front subject image and outputs a photoelectric conversion signal is disposed on the front surface, and the rear subject image is captured on the rear surface. In the digital camera in which the second imaging unit that outputs the photoelectric conversion signal and the display unit capable of displaying an image are photographed, when photographing one subject, the rear subject is enlarged and photographed with the rear imaging device, It is possible to display the subject in front through on the monitor placed on the back and to display the through image of the enlarged back subject image in the window so that the camera shake situation can be emphasized and displayed. that provides a digital camera to be.

Further, in the invention according to claim 2, the first imaging unit and the second digital camera of the mounting serial to claim 1, characterized in that it comprises a simultaneous photographing mode for performing substantially simultaneously captured by the imaging unit of provide.

In the third aspect of the present invention, the first imaging unit that captures the front subject image and outputs a photoelectric conversion signal is arranged on the front surface, and the rear subject image is captured on the rear surface and the photoelectric conversion signal is output. When a front subject is photographed on a computer of a digital camera having a second image pickup unit and a display unit capable of displaying an image, a rear image sensor is used to magnify and photograph the rear subject, and There is provided a program for executing a function of displaying a subject in front on a disposed monitor and a function of displaying a through image of a rear subject image enlarged in a window substantially simultaneously.

According to the present invention, when one of the two image sensors provided in the digital camera captures a subject, an enlarged image of the subject can be captured with the other image sensor and displayed in a through window. Therefore, it is possible to display at a higher processing speed than when an enlarged image is displayed on a part of the screen by performing parallel processing and shooting with one image sensor. In addition, by displaying an enlarged image, the camera shake state is amplified when there is a camera shake, so that the camera shake state can be confirmed without a sensor for detecting the camera shake.

(Embodiment 1)
Hereinafter, a first embodiment when the present invention is applied to a digital camera will be described with reference to the drawings.

1A and 1B are diagrams showing an example of an external configuration of a digital camera to which the present invention is applied. FIG. 1A is a perspective view from the front, and FIG. 1B is a perspective view from the back.
The digital camera 1 is provided with a front side imaging unit (hereinafter referred to as a subject imaging unit) 20-1, a self-timer lamp 3, an optical viewfinder window 4, and a strobe light emitting unit 5 on the front surface of a substantially rectangular thin plate body. Comprises a power key 6 and a shutter key 7.

  In order to mount the photographing lens 2-1 of the subject imaging unit 20-1 on a thin body, for example, it is assumed that it is a single focus lens and has a fixed focus, and does not perform a zoom operation or a focusing operation.

  The power key 6 is a key for turning on / off the power each time it is pressed, and the shutter key 7 functions as a key for instructing the release in the shooting mode, and for setting / execution in the menu selection or the like. .

  Also, on the back of the digital camera 1, a monitor side imaging unit 20-2 including a photographing lens 2-2, a mode switch (SW) 8, a menu key 9, a cross key 10, an optical viewfinder 11, a strobe charge lamp 12, and A display unit 13 is provided.

  The rear side imaging unit (hereinafter referred to as the monitor side imaging unit) 20-2 is for self-portrait, is focused on 50 to 100 cm, and the angle of view to be shot is also 50 to 100 cm away (that is, the photographer). The angle of view is suitable for capturing images. The monitor-side imaging unit 20-2 is configured to change the imaging direction, and the imaging direction can be changed within a predetermined range, so that the user does not necessarily have to be located directly behind the camera.

  The user can select a sensor imaging mode in which one of the subject imaging unit 20-1 and the monitor-side imaging unit 20-2 is used for imaging. In addition, the subject imaging unit 20-1 and the monitor-side imaging unit 20-2 capture a subject and a photographer at substantially the same time, and synthesize and display simultaneously photographed images, and enlarge the image of the photographer side that has been photographed simultaneously. Then, it is possible to display a window on a monitor screen through which the subject image is displayed, and to select a camera shake discrimination mode in which the camera shake state of the camera can be recognized from the blur of the subject image. It is also possible to select only one of the subject imaging unit 20-1 and the monitor-side imaging unit 20-2 and perform shooting only with the selected imaging unit.

  The mode switch 8 is constituted by a slide switch, for example, and switches between the photographing mode “R” and the reproduction mode “P”.

The display unit 13 is composed of a color liquid crystal panel with a backlight, and displays a monitor image as an electronic viewfinder in the shooting mode, while displaying a selected playback image in the playback mode. When the simultaneous shooting mode is selected, images captured by the subject imaging unit 20-1 and the monitor-side imaging unit 20-2 are combined and displayed, or one image is displayed in a window.
Although not shown, a memory card slot with a lid is provided on the lower surface of the body, and a memory card as a recording medium of the digital camera 1 is detachably attached.

  FIG. 2 is a diagram showing an embodiment of the electronic circuit configuration of the digital camera 1. The digital camera 1 includes a drive motor 21-1, an optical system lens 22-1 including a photographing lens 2-1, and an imaging device. CCD 23-1, timing generator (TG) 24-1, vertical driver 25-1, sample hold circuit (S / H) 26-1, A / D converter 27-1, drive motor 21-2, photographing lens 2-2 including an optical system lens 22-2, a CCD 23-2 as an imaging device, a timing generator (TG) 24-2, a vertical driver 25-2, a sample hold circuit (S / H) 26-1A / D. Converter 27-2, color process circuit 28, DMA (Direct Memory Access) controller 29, DRAM interface (I / F) 30, DRAM 31, Control unit 32, VRAM controller 33, VRAM34-1,34-2, digital video encoder 35, a key input unit 36, JPEG circuit 37, storage memory 38, and a signal combining circuit 39 and the display unit 13.

  Assume that the DRAM 31 has an area for storing subject image data for one frame from the CCD 23-1 and an area for storing monitor-side image data for one frame from the CCD 23-2. Instead of the DRAM 31, a DRAM that stores subject image data from the CCD 23-1 and a DRAM that stores monitor-side image data from the CCD 23-2 may be provided. Further, the signal synthesis circuit 39 may be provided as necessary.

  The drive motor 21-1, the optical system lens 22-1, including the taking lens 2, and the CCD 23-1, the timing generator 24-1, and the vertical driver 25-1 are the subject imaging unit 20 (the first imaging unit 20) shown in FIG. 1), the driving motor 21-2, the optical system lens 22-2 including the photographing lens 2-2 and the CCD 23-2, the timing generator 24-, and the vertical driver 25-2 are shown in FIG. The circuit of the monitor side imaging unit 20-2 (second imaging unit) shown in (b) is configured.

  The two image capturing units can perform only one image capturing or simultaneous image capturing in the simultaneous image capturing mode under the control of the control unit 32 based on a user instruction from the key input unit 36. In the case of the simultaneous shooting mode, shooting by time division control is performed. Further, AE (Automatic Exposure) is performed separately for the imaging unit 20-1 and the imaging unit 20-2.

  When the subject imaging unit 20-1 performs shooting in the monitoring mode of the shooting mode, the aperture position is moved by driving the motor 21-1 driven by a drive control signal from the control unit 32. The CCD 23-1 disposed behind the photographing optical axis of the optical system lens 22-1 including the photographing lens 2-1 is scan-driven by the vertical driver 25-1 based on the timing signal from the timing generator 24-1. A photoelectric conversion output for a light image formed at regular intervals is output for one frame.

  Similarly, at the time of shooting by the monitor-side imaging unit 20-2, the aperture position is moved by driving a motor 21-2 that is driven by a drive control signal from the control unit 32. The CCD 23-2 disposed behind the photographing optical axis of the optical system lens 22-2 including the photographing lens 2-2 is scanned and driven by the vertical driver 25 on the basis of the timing signal from the timing generator 24, and at regular intervals. A photoelectric conversion output for the formed optical image is output for one frame.

  In the simultaneous photographing mode, the control unit 32 controls the timing signals generating operations of the motors 21-1 and 21-2 and the timing generators 24-1 and 24-2 in a time-sharing manner and also uses the vertical driver 25-1. , 25-2 signal output destinations (CCD 23-1, CCD 23-2) are switched in synchronism with the scanning timing, and CCD 23-1 and CCD 23-2 are driven to scan, and an optical image formed at regular intervals. Output one frame of photoelectric conversion output.

    The photoelectric conversion output from the CCD 23-1 or the CCD 23-2 is appropriately gain-adjusted for each RGB primary color in an analog value state, and then sample-held by the sample hold circuit 26-1.6-2, and A / D converted. The digital data is converted into digital data by the units 27-1 and 27-2, and color processing including pixel interpolation processing and γ correction processing is performed by the color processing circuit 28 (see FIG. 3). Signals Cb and Cr (hereinafter referred to as image data) are generated and output to the DMA controller 29. In the case of the simultaneous photographing mode, the color process processing results based on the photoelectric conversion output from the CCD 23-1 and the photoelectric conversion output from the CCD 23-2 are separately output to the DMA controller 29.

    The DMA controller 29 once writes the image data output from the color process circuit 28 to the buffer in the DMA controller 29 once using the composite synchronization signal, memory write enable signal, and clock signal from the color process circuit 28, respectively. DMA transfer to the DRAM 31 used as a buffer memory via

    The buffer in the DMA controller 29 has two buffers (or two writing areas) for writing the result of the color process based on the photoelectric conversion output from the CCD 23-1 and the photoelectric conversion output from the CCD 23-2. In the case of simultaneous shooting, the data is sequentially read from each buffer (or each writing area), DMA-transferred to the DRAM 31, and transferred to the two writing areas assigned to the DRAM 31. Write each.

    The control unit 32 includes a CPU, a ROM in which an operation program executed by the CPU and an imaging operation program are fixedly stored, a RAM used as a work memory, and the like, and controls the entire digital camera 1. Thus, after the DMA transfer of the luminance and color difference signals to the DRAM 31 is completed, the image data is read from the DRAM 31 via the DRAM interface 30 and is used for the VRAM 34-1 for the subject image or the monitor side image via the VRAM controller 33. Write to VRAM 34-2.

    In the case of the simultaneous shooting mode, the image data of the subject image and the monitor-side image written in the two writing areas assigned to the DRAM 31 are sent via the VRAM controller 33 to the VRAM 34-1 and VRAM 34- 2 is written at a predetermined timing.

  The digital video encoder 35 periodically reads out the image data from the VRAM 34 via the VRAM controller 33, generates a video signal based on these data, and outputs the video signal to the display unit 13. In the case of the simultaneous shooting mode, the video signal of the monitor side image is overwritten and combined with the video signal of the subject image written in the VRAM 34-1, and is displayed through on the display unit 13 (see FIGS. 5 and 6). In the camera shake discrimination mode, the monitor-side image is enlarged and displayed through in the window (see FIGS. 7 and 8).

  As described above, the display unit 13 functions as a monitor display unit (electronic finder) in the shooting mode, and performs display based on the video signal from the digital video encoder 35 to capture from the VRAM controller at that time. An image based on image information is displayed in real time (through image display). In the camera shake discrimination mode, the enlarged photographer image is displayed in a window on the through image.

  When the user operates the shutter key 7 (see FIG. 1) constituting the key input unit 36 at a timing when a still image is desired to be captured while the current image is displayed on the display unit 13, a trigger signal is generated. appear.

  In response to the trigger signal, the control unit 32 immediately transfers the image data for one frame captured from the CCD 23-1 and / or the CCD 23-2 to the DRAM 31 from the CCD 23-1 and / or the CCD 23-2. Is stopped, and the recording / saving state (image recording mode) is entered.

  In the recording and storage state, the control unit 32 stores the image data for one frame written in the DRAM 31 through the DRAM interface 30 for each of the Y, Cb, and Cr components in a basic block of 8 pixels × 8 pixels. The data is read in units and written in a JPEG (Joint Photographic Exploring Group) circuit 37, and this JPEG circuit 37 uses ADCT (Adaptive Discrete Cosine Transform: Adaptive Discrete Cosine Transform), a Huffman coding process such as an entropy coding method. To do. Then, the obtained code data is read out from the JPEG circuit 37 as a data file of one image, and is stored in a non-volatile memory such as a flash memory enclosed in a memory card that is detachably mounted as a recording medium of the digital camera 1. Write to memory 38. The storage memory 38 may be built in the digital camera 1 separately from the memory card.

  As the image data for one frame is compressed and all compressed data is written to the storage memory 38, the control unit 32 activates the path from the CCD 23-1 or the CCD 23-2 to the DRAM 31 again.

  In the case of the simultaneous shooting mode, in the recording and storing state, the control unit 32 stores the image data of the subject image for one frame written in the subject image data area assigned to the DRAM 31 by the signal synthesis circuit 39. The image data of the monitor side image written in the monitor side image data area is combined, and the combined image data is compressed by the JPEG circuit 37 via the DRAM interface 30. The acquired code data is read out from the JPEG circuit 37 as a data file of one image and written into the storage memory 38.

  In the above description, in the case of simultaneous shooting, the combined image data of the subject image and the monitor-side image is compressed and stored in the storage memory 38 in the record storage state. The subject image data for one frame and the monitor-side image data written in the DRAM 31 are respectively compressed. For example, the subject image data file name is “1-A” and the monitor-side image data file name is “1-B”. Or the like may be written in the storage memory 38 in association with each other. Alternatively, the user may be able to select and set whether to write as a composite image in the storage memory 38 or as a separate image and write it into the storage memory 38.

  The key input unit 36 includes the power key 6, the shutter key 7, the mode switch 8, the menu key 9, and the cross key 10 described above, and signals associated with these key operations are directly sent to the control unit.

  In the playback mode, the control unit 32 selectively reads out the image data recorded in the storage memory 38, decompresses the image data in the same procedure as the data compression in the shooting mode by the JPEG circuit 37, and decompresses the decompressed image data into the VRAM. The data is developed and stored in the VRAM 34 via the controller 33, and then periodically read out from the VRAM 34. A video signal is generated based on these image data and reproduced and output on the display unit 13.

  In the case of the simultaneous shooting mode, when a composite image is generated and written in the storage memory 38, the composite image data is played back in the same manner as described above in the playback mode, and the VRAM 34 is supplied via the VRAM controller 33. Then, it is periodically read out from the VRAM 34, and a video signal is generated based on these image data and reproduced and output on the display unit 13.

  In the case of the simultaneous shooting mode, when the subject image data and the monitor-side image data are compressed and written in the storage memory 38 in association with each other, the subject image data is read from the storage memory 38 in the playback mode. And the monitor-side image data associated therewith are selectively read out to reproduce the image data in the same procedure as described above, and the video signals generated based on these image data are synthesized and the VRAM 34 via the VRAM controller 33. After being expanded and stored, it is periodically read out from the VRAM 34 and output to the display unit 13.

(White balance processing operation)
FIG. 3 is an explanatory diagram of AWB (white balance) processing in the color process circuit. In this example, the color process circuit 28 includes a digital clamp 280-1, an AE integrator 280-2, an AF filter 280-3, The image processing system includes a WB gain multiplication circuit 282, a gamma correction circuit 283, an image generation circuit 284, a YIQ conversion circuit 286, a white detection circuit 287, and a WB coefficient determination circuit 288. The YIQ conversion circuit 286, the white detection circuit 288, and the WB coefficient determination circuit 289 constitute a WB coefficient calculation block 285. Reference numerals 281-1, 281-2, 281-3, 285-1, and 285-2 indicate the open state when used as a sensor in the sensor photographing mode, and the scanning timing in the simultaneous photographing mode and the camera shake discrimination mode. It is a switch that is controlled to be opened and closed in synchronism, and means an electronic switch or a switch under program control.

In FIG. 3, when the switches 281-1, 281-2, and 281-3 are in the closed state in the sensor photographing mode (that is, when photographing by the subject imaging unit 20-1), the photographing lens 2-1 is used. The captured optical image is converted into an electrical signal (image signal) by the CCD 23-1 and output. The image signal output from the CCD 23-1 is sampled and A / D converted, converted into Bayer format data by the digital clamp 280-1, and supplied to the WB gain multiplication circuit 24 and the YIQ conversion circuit 286 at a predetermined timing. . Next, the WB gain multiplication circuit 282 multiplies the WB coefficient (white balance coefficient), and then the gamma correction circuit 283 performs image interpolation processing. The image generation circuit 284 generates a video signal and outputs it to the DMA controller 29. On the other hand, the WB coefficient is determined by the WB coefficient calculation block including the YIQ conversion circuit 27, the white detection circuit 28, and the WB coefficient determination circuit 29 from the data supplied to the YIQ conversion circuit 286. This is fed back to the WB gain multiplication circuit 24. At this time, since the switches 285-1 and 285-2 are in the open state (that is, when the monitor-side imaging unit 20-2 is used as a sensor), the optical image captured by the photographing lens 2-2 is It is converted into an electrical signal (image signal) by the CCD 23-2 and output. The image signal output from the CCD 23-2 is sampled and A / D converted, converted into Bayer format data by the digital clamp 280-1, and given to the YIQ conversion circuit 286 at a predetermined timing. Added to the data.
The AE integrator 280-2 integrates the input signal from the subject imaging unit 20-1 and outputs the integrated value to the control unit 32. The AF filter 280-2 receives the signal from the subject imaging unit 20-1. In order to detect a high frequency for contrast autofocus from the input signal, a high-pass filter (HPF) is applied to the input signal, and an integrated value of the output is output to the control unit 32.

When the switches 281-1, 281-2, and 281-3 are in the open state (that is, when the subject imaging unit 20-1 is used as a sensor), the switches 285-1 and 285-2 are in the closed state (monitoring). The optical image captured by the photographing lens 2-2 is converted into an electrical signal (image signal) by the CCD 23-2 and output. The image signal output from the CCD 23-2 is sampled and A / D converted, converted into Bayer format data by the digital clamp 280-1, and supplied to the WB gain multiplication circuit 24 and the YIQ conversion circuit 286 at a predetermined timing. . The WB gain multiplication circuit 282 multiplies the WB coefficient (white balance coefficient), and then the gamma correction circuit 283 performs image interpolation processing. The image generation circuit 284 generates a video signal and outputs it to the DMA controller 29. On the other hand, the WB coefficient is determined by the WB coefficient calculation block including the YIQ conversion circuit 27, the white detection circuit 28, and the WB coefficient determination circuit 29 from the data supplied to the YIQ conversion circuit 286. This is fed back to the WB gain multiplication circuit 24. The optical image captured by the photographing lens 2-1 is converted into an electrical signal (image signal) by the CCD 23-1 and output. The image signal output from the CCD 23-2 is sampled and A / D converted, converted into a Bayer format data by the digital clamp 280, supplied to the YIQ conversion circuit 286 at a predetermined timing, and converted into data from the CCD 23-2. Is added.
The AE integrator 280-2 integrates the input signal from the subject imaging unit 20-1 and outputs the integrated value to the control unit 32.

  In the simultaneous shooting mode and the camera shake discrimination mode, the switches 281-1, 281-2, and 281-3 are closed by time division control (that is, when shooting is performed by the subject imaging unit 20-1). When the switches 285-1 and 285-2 are opened and the monitor-side imaging unit 20-2 is used as a sensor, and the switches 285-1 and 285-2 are closed (that is, by the subject imaging unit 20-2). At the time of shooting), the switches 2811, 281-2, and 281-3 are opened, and the monitor-side imaging unit 20-1 is used as a sensor.

  FIG. 4 shows a photographing operation in the sensor photographing mode, that is, the digital camera 1 in the case where either one of the subject imaging unit or the monitor side imaging unit captures an image and the other one is used as a sensor for collecting photographing information. It is a flowchart for demonstrating operation | movement. This flowchart is for explaining a program for causing the digital camera 1 to implement the photographing method of the present invention, and may be configured as one of subprograms of the photographing operation program, or may be an independent program (for example, , “Shooting program in sensor imaging mode”).

  The processing shown below will be basically explained by an example in which the CPU of the control unit 32 executes according to a program stored in advance in the program memory, but it is not necessary to store all functions in the program memory. It may be realized by receiving part or all via a network (the same applies to FIGS. 5 and 7). Hereinafter, description will be given based on FIGS.

  When the photographer selects the sensor photographing mode, in FIG. 4, the control unit 32 closes the switches 181-1, 181-2, 181-3 of the color process circuit 28 (FIG. 3), and switches 185-1, 185-2 is opened (step S1).

  Next, the control unit 32 executes AE processing at the focal length (corresponding to the zoom value) at that time, and the subject imaging unit 20-1 converts the subject light image incident from the photographing lens 2-1 from the TG 24-1. Based on the timing signal, the CCD 23-1 is driven and controlled by the vertical driver 25-1, the subject image is captured and subjected to photoelectric conversion, and a digital image signal is obtained through the path of the sample hold circuit 25-1 and AD conversion circuit 26-1. To the color process circuit 28. At substantially the same time, the photographer side light image (photographer image or the like) incident from the photographing lens 2-2 is captured by the monitor image capturing unit 20-2, and the vertical driver 25-2 based on the timing signal from the TG 24-2. The CCD 23-2 is driven and controlled to photoelectrically convert a photographer side light image (photographer image and its background image) to obtain a digital image signal through the path of the sample hold circuit 25-2 and AD conversion circuit 26-2. Is output to the color process circuit 28 (step S2).

  The image signal from the subject imaging unit 20-1 is converted to Bayer format data by the digital clamp 280, and is supplied to the WB gain multiplication circuit 24 and the YIQ conversion circuit 286 at a predetermined timing, and the monitor side imaging unit 20-2 The image signal from is converted to Bayer format data by the digital clamp 280 and is supplied to the YIQ conversion circuit 286 at a predetermined timing. That is, the color process circuit 28 adds the input signal from the monitor-side imaging unit 20-2 to the image signal from the subject imaging unit 20-1, and performs white balance processing so as to achieve white balance corresponding to the color of the light source. (Step S3), the gamma correction circuit 283 performs image interpolation processing, the image generation circuit 284 generates a video signal, and the DMA signal is transferred to the DRAM 31 via the DMA controller 29 and the DRAM interface (I / F) 30. Transfer (step S4).

In addition, through image data from the subject imaging unit 20-1 is generated together with DMA transfer from the color process circuit 28 to the DRAM 31, and through image data is generated, and the VRAM controller 33 is controlled to generate the VRAM 34-1. The video signal is rewritten, and a finder video (through image) is displayed on the display unit 13 via the digital video encoder 35 (step S5).
The control unit 32 checks the signal from the key input unit 36 to determine whether or not the shutter key 7 has been pressed halfway. If the shutter key 7 has been pressed halfway, the process proceeds to step S7. If not, the process returns to step S2 ( Step S6).

  Next, the control unit 32 controls the AF driving unit 11-2 so as to focus on a predetermined focus area, and performs an automatic focusing process, that is, moves the focus lens 12-1 to perform a focusing operation. At the same time, AE control (including aperture control) and AWB control (see steps S2 and S3) are performed. When the focusing process is completed, the focusing position is locked and the process proceeds to step S8. Although not shown, the through image is displayed even during the focusing operation (step S7).

  The control unit 32 checks the signal from the key input unit 30 to determine whether or not the shutter key 7 has been fully pressed. If the shutter key 7 has been fully pressed, the process proceeds to step S9 (step S8).

  When the shutter key 7 is fully pressed, the path from the subject imaging unit 20-1 to the DRAM 31 is immediately stopped at that time, and switching to the CCD driving method at the time of main photographing different from the through image acquisition is executed. Then, after the image compression processing is performed on the captured image data, the compressed image data (image file) is recorded in the storage memory 38, and the image capturing for one frame is finished (step S9).

  By the operation shown in the flowchart of FIG. 4, when the subject imaging unit 20-1 captures a subject, the photoelectric conversion output from the monitor-side imaging unit 20-2 is converted into image information adjustment data during imaging such as white balance processing. Therefore, the photographing of the subject and the acquisition of information such as the brightness around the monitor and the light source can be performed simultaneously. That is, since the front and back imaging elements capture light from different shooting areas, information on the surrounding light sources such as the back of the photographer can be obtained more reliably when shooting the subject. Based on this information, shooting conditions such as white balance can be set and the subject can be shot.

  In the description of the flowchart of FIG. 4 above, an example is shown in which the subject imaging unit 20-1 captures a subject (photographing the other party) and the monitor side imaging unit 20-2 is used as a sensor. The present invention can also be applied to a case where photographing (self-portrait) is performed with the imaging unit 20-2 and the subject imaging unit 20-1 is used as a sensor. However, in this case, the switches 181-1, 181-2, 181-3 are opened, the switch 185 is closed, and the photographer side image is captured from the CCD 23-2. In addition, since the monitor-side imaging unit 20-2 does not perform a zoom operation in this embodiment, the zoom operation in step S1 is not performed. In addition, since the focus is fixed and no focusing process is performed, the half-pressing operation detection of the shutter key 7 in step S6 and the AF to AWB operations in step S7 are not performed. If the shutter key 7 is not fully pressed, the process returns to step S2.

  When the digital camera 1 is configured to perform the zoom operation with the monitor-side imaging unit 20-2, the switches 181-1, 181-2, 181-3 are opened at step T1 in the flowchart of FIG. Then, the switch 185 is closed, and the photographer side image is taken in from the CCD 23-2.

(Embodiment 2)
FIG. 5 is a flowchart for explaining the shooting operation in the simultaneous shooting mode, that is, the operation of the digital camera 1 when the subject imaging unit and the monitor-side imaging unit capture images substantially simultaneously. Is an example configured to record a composite image of the subject side image and the monitor side image, and FIG. 5B illustrates an example configured to record the subject side image and the monitor side image in association with each other.
This flowchart is for explaining a program for causing the digital camera 1 to implement the photographing method of the present invention, and may be configured as one of subprograms of the photographing operation program, or may be an independent program (for example, , “Shooting program in simultaneous shooting mode”). Hereinafter, a series of operations of the imaging units 2-1 and 2-2 related to the white balance processing will be described with reference to FIGS.

  In FIG. 5A, when the photographer selects the simultaneous photographing mode, the control unit 32 executes AE processing at the focal length (corresponding to the zoom value) at that time, and the subject imaging unit 20-1 takes the photographing lens. The subject light image incident from 2-1 is driven and controlled by the vertical driver 25-1 based on the timing signal from the TG 24-1, the CCD 23-1 is driven and captured, and the subject image is photoelectrically converted to a sample hold circuit 25-1. A digital image signal is obtained through the path of the AD conversion circuit 26-1 and is output to the color process circuit 28. At the same time, the photographer-side light image incident on the photographing lens 2-2 (photographer image and its background image) is monitored by the monitor-side image pickup unit 20-2 and the vertical driver 25 based on the timing signal from the TG 24-2. -2 drives and controls the CCD 23-2, photoelectrically converts the photographer's side light image, and forms an image on the CCD-23-1 at regular intervals through the path of the sample hold circuit 25-2 and AD conversion circuit 26-2. A digital image signal for one frame corresponding to the optical image is obtained and output to the color process circuit 28. At substantially the same time, the AE process is executed at a fixed focal length, and the subject imaging unit 20-2 converts the subject light image incident from the photographing lens 2-2 based on the timing signal from the TG 24-2. 2, the CCD 23-2 is driven and controlled, the subject image is taken in, subjected to photoelectric conversion, a digital image signal is obtained through the path of the sample hold circuit 25-2 and the AD conversion circuit 26-2, and is output to the color process circuit 28. At substantially the same time, the photographer-side light image photographer image and its background image incident from the photographing lens 2-2 are monitored by the monitor-side imaging unit 20-2 and the vertical driver 25- based on the timing signal from the TG 24-2. 2, the CCD 23-2 is driven and controlled to photoelectrically convert the photographer's side light image (photographer image and its background image) at regular intervals along the path of the sample hold circuit 25-2 and AD conversion circuit 26-2. A digital image signal for one frame with respect to the optical image formed on the CCD-23-2 is obtained and output to the color process circuit 28 (step T1).

  The control unit 32 first closes the switches 181-1, 181-2, and 181-3 of the color process circuit 28 (FIG. 3) at every output timing of the image signal for one frame (that is, at the fixed time). The switches 185-1 and 185-2 are opened in the first state (subject imaging unit active state), the switches 185-1 and 185-2 are closed, and the switches 181-1, 181-2 and 181-3 are closed. The second state (monitor side imaging unit active state) is released (step T2).

  In the first state, the color process circuit 28 supplies the image signal from the subject imaging unit 20-1 to the WB gain multiplication circuit 24 and the YIQ conversion circuit 286 as data in the Bayer format by the digital clamp 280, and captures the subject. The image signal from the unit 20-2 is converted into Bayer format data by the digital clamp 280 at a predetermined timing, and is supplied to the YIQ conversion circuit 286. That is, the color process circuit 28 adds the input signal from the monitor-side imaging unit 20-2 to the image signal from the subject imaging unit 20-1, and performs white balance processing so as to achieve white balance corresponding to the color of the light source. (Step T3), the image interpolation processing is performed by the gamma correction circuit 283, the video signal is generated by the image generation circuit 284, and the DMA signal is transferred to the DRAM 31 via the DMA controller 29 and the DRAM interface (I / F) 30. The data is transferred and stored in the subject-side image storage area of the DRAM 31, and the process proceeds to Step T7 (Step T4).

  Further, the control unit 32 generates through image data by thinning out the image data from the subject imaging unit 20-1 together with the DMA transfer from the color process circuit 28 to the DRAM 31 in step T 4, and controls the VRAM controller 33. Then, the VRAM 34-2 is rewritten with the through image data that has generated the image data (step T5).

  In the second state, the color process circuit 28 supplies the image signal from the monitor-side imaging unit 20-2 to the WB gain multiplication circuit 24 and the YIQ conversion circuit 286 as data in the Bayer format by the digital clamp 280, and the subject The image signal from the imaging unit 20-1 is converted to Bayer format data by the digital clamp 280 at a predetermined timing, and is supplied to the YIQ conversion circuit 286. That is, the color process circuit 28 adds the input signal from the subject imaging unit 20-2 to the image signal from the monitor-side imaging unit 20-2 and performs white balance processing so as to achieve white balance corresponding to the color of the light source. (Step T6), the image interpolation processing is performed by the gamma correction circuit 283, the video signal is generated by the image generation circuit 284, and the DMA signal is transferred to the DRAM 31 via the DMA controller 29 and the DRAM interface (I / F) 30. The data is transferred and stored in the monitor-side image storage area of the DRAM 31, and the process proceeds to Step T8 (Step T7).

  Further, the control unit 32 performs the DMA transfer from the color process circuit 28 to the DRAM 31 in step T7, and the through image data reduced by a predetermined ratio after thinning out the image data from the monitor side imaging unit 20-2. As shown in the example of FIG. 6, the monitor-side image 132 is generated at a predetermined position on the subject-side image 131 in the subject-side video signal generated and stored in the VRAM 34-1 by controlling the VRAM controller 33. The image on the monitor side is superimposed (overwritten) and superimposed on the display unit 13 via the digital video encoder 35 so as to be superimposed (overwritten) and displayed at a predetermined position on the screen of the display unit 13. The finder image (through image) is displayed (step T8).

  The control unit 32 checks the signal from the key input unit 36 to determine whether or not the shutter key 7 has been pressed halfway. If the shutter key 7 has been pressed halfway, the process proceeds to step T10, and if not, the process returns to step T2 ( Step T9).

  The control unit 32 then controls the AF driving unit 11-2 so that the subject imaging unit 20-1 is focused on a predetermined focus area to perform automatic focusing processing, that is, the focus lens 12-1. Is moved to perform the focusing operation, and AE control (including aperture control) and AWB control (see steps T1 to T3) of the subject imaging unit 20-1 and the monitor-side imaging unit 20-2 are performed to perform the focusing process. When is finished, the in-focus position is locked and the process proceeds to Step T11. Although not shown, the through image is displayed even during the focusing operation (step T10).

  The control unit 32 checks the signal from the key input unit 30 to determine whether or not the shutter key 7 has been fully pressed, and if the shutter key 7 has been fully pressed, the process proceeds to step T12 (step T11).

  When the shutter key 7 is fully pressed, the path from the subject imaging unit 20-1 and the monitor-side imaging unit 20-2 to the DRAM 31 is immediately stopped at that time, and the CCD at the time of main shooting is different from that at the time of through image acquisition. Switching to the driving method is executed to store the image data from the subject imaging unit 20-1 and the monitor side imaging unit 20-2 in the subject side image storage area and the monitor side image storage area of the DRAM 31, respectively (step T12). The image data stored in the monitor-side image storage area is reduced, and the monitor-side image is superposed so that the reduced monitor-side image is positioned at a predetermined position of the subject-side image (overwrite synthesis) (step T13), and synthesized. After image compression processing is performed on the image data, the compressed image data (image file) is recorded in the storage memory 38, and the composite image for one frame is shot. That (step T14).

  When the subject imaging unit 20-1 and the monitor-side imaging unit shoot substantially simultaneously by the operation shown in the flowchart of FIG. 5A, the subject imaging unit at the timing of data output for one frame from the CCD. 20-1 is a period in which the photoelectric conversion output from the monitor-side imaging unit 20-2 is used as complementary data for white balance processing, and the image signal from the monitor-side imaging unit 20-2 is the subject imaging unit 20-1. Since the cycle of using the photoelectric conversion output from the white balance processing as complementary data is switched, it is possible to simultaneously perform photographing of the subject or the photographer and detection of the surrounding incident light state. In other words, since light from different imaging areas is incident on the front and back imaging elements, ambient light source information can be obtained more reliably during imaging. Then, based on this information, it is possible to photograph the subject and the photographer by setting photographing conditions such as white balance.

(Modification 1)
In the example of FIG. 5A, as shown in steps S13 and S14, the image captured by the subject imaging unit 20-1 and the image captured by the monitor-side imaging unit 20-2 are combined and recorded in the storage memory 38. However, as shown in FIG. 5B, the image captured by the subject imaging unit 20-1 and the image captured by the monitor side imaging unit 20-2 are separately compressed (step T13 ′), and the compressed subject The image captured by the imaging unit 20-1 and the image captured by the monitor side imaging unit 20-2 may be associated with each other and recorded in the storage memory 38 (step T14 ′). In this case, the reproduced image can be displayed after being reproduced during reproduction.

FIG. 6 is a diagram illustrating an example of a composite image of the subject image and the monitor-side image displayed in the monitoring state in the simultaneous shooting mode.
In the digital camera 1, when the simultaneous photographing mode is selected, the subject image 131 from the photographing lens 2-1 (FIG. 1 (a)) in front of the camera and the photographing lens 2-2 (FIG. 1 (b)) in the rear of the camera. ) From the monitor side 132 is synthesized and displayed as shown in FIG. The user can obtain a still image by operating the shutter key 7 at a desired timing.

  In the example of FIG. 6 described above, the combination part of the monitor-side image is the lower right corner, but is not limited to this. Alternatively, an image composition area selection field may be displayed, and when the user operates a key on the input unit 36 to select a desired display area, a monitor image is synthesized and displayed on the selected display area. Good.

  In the example of FIG. 6, the monitor side image captured by the photographic lens 2-1 is combined and displayed in the subject image captured by the photographic lens 2-1, but the two layouts are switched and the subject image is displayed in the monitor side image. You may enable it to be displayed compositely. For example, when the monitor image synthesized in the subject image is clicked with a mouse or the like, the layout is switched, and a synthesized image obtained by synthesizing the subject image may be displayed in the monitor side image.

(Modification 2)
In the second embodiment, the image captured from the subject imaging unit 20-1 and the reduced image of the image captured by the monitor-side imaging unit 20-2 are combined and displayed through substantially at the same time, but the monitor-side image is enlarged and displayed in the window. By displaying through, it can be used to prevent camera shake.

  FIG. 7 is a flowchart for explaining the operation of the digital camera 1 in the camera shake prevention photographing mode. This flowchart is for explaining a program for causing the digital camera 1 to implement the photographing method of the present invention, and may be configured as one of subprograms of the photographing operation program, or may be an independent program (for example, , “Shooting program in camera shake prevention shooting mode”). Hereinafter, a series of operations of the imaging units 2-1 and 2-2 related to the white balance processing will be described with reference to FIGS.

  In FIG. 7, the operations of steps U1 to U7 are the same as steps T1 to T7 of the flowchart shown in FIG. Therefore, when the camera shake prevention shooting mode is selected, the control unit 32 controls the digital camera 1 to perform the same operation as steps T1 to T7 in the flowchart of FIG. 5 (steps U1 to U7).

  Next, along with the DMA transfer from the color process circuit 28 to the DRAM 31 in step U7, the control unit 32 enlarges the image data from the monitor-side imaging unit 20-2 and generates through image data (step S7). U8) After the thinning process is performed, a window is displayed as a through image on the monitor screen of the display unit 13 via the VRAM controller 33 and the digital video encoder 35 (see FIG. 8) (step U9).

  The control unit 32 checks the signal from the key input unit 36 to check whether or not the shutter key 7 has been half-pressed. If the shutter key 7 is half-pressed, the control unit 32 proceeds to Step U11. If not, the control unit 32 returns to Step U2 ( Step U10).

  Next, the control unit 32 controls the AF driving unit 11-2 so as to focus on a predetermined focus area, and performs an automatic focusing process, that is, moves the focus lens 12-1 to perform a focusing operation. AE control (including aperture control) and AWB control (see Steps U1 to U3) are performed, and when the focusing process is completed, the focusing position is locked and the process proceeds to Step U12. Although not shown, the through image is displayed even during the focusing operation (step U11).

  The control unit 32 checks the signal from the key input unit 30 to determine whether or not the shutter key 7 has been fully pressed. If the shutter key 7 has been fully pressed, the process proceeds to step U13 (step U12).

  When the shutter key 7 is fully pressed, the path from the subject imaging unit 20-1 to the DRAM 31 is immediately stopped at that time, and switching to the CCD driving method at the time of main shooting different from the through image acquisition is executed. Then, after the image compression processing is performed on the captured image data, the compressed image data (image file) is recorded in the storage memory 38, and the image capturing for one frame is finished (step U13).

  By the operation shown in the flowchart of FIG. 7, when the subject imaging unit 20-1 captures a subject, the monitor side imaging unit 20- is displayed on the monitor screen on which the through image captured by the subject imaging unit 20-1 is displayed. Since the back-side subject (usually the photographer) captured in step 2 is enlarged and displayed in the window, the camera shake state is amplified and displayed. When the camera shakes, the image displayed in the window moves vertically or horizontally. Since it appears to be swaying, the photographer can recognize that camera shake has occurred, and can suppress camera shake by re-setting the camera. Therefore, even if the digital camera 1 is not particularly equipped with a blur detection sensor, an image free from camera shake can be obtained. In addition, since there are two CCDs, the camera shake state can be highlighted on the enlarged image and the state of the camera shake can be confirmed without slowing down the processing speed by parallel processing or the like as in the case of one CCD. . In addition, the enlarged image of the window can be obtained not only by electronic zoom but also by optical zoom.

  FIG. 8 is a diagram illustrating an example of a composite image of the subject image and the monitor-side image displayed in the monitoring state in the camera shake prevention shooting mode. In the digital camera 1, when the anti-shake shooting mode is selected, the subject image 131 from the shooting lens 2-1 (FIG. 1 (a)) in front of the camera is displayed through, and the shooting lens 2-2 ( The monitor-side image 133 (photographer image in this example) from FIG. 1B is enlarged and displayed in a window. Reference numeral 133 denotes a blurred image. Since the movement of the enlarged image 133 is easy to detect, the photographer can determine that there is camera shake when the image 133 displayed in the window 135 moves up and down or left and right. If the shutter key 7 is operated at the timing when the movement of the image 133 stops by performing the blur suppression operation, a still image without camera shake can be obtained.

  In the example of FIG. 8, the display location of the window 135 is the lower right corner, but the present invention is not limited to this. Further, the cross key 10 can be operated to move the window 135 to a desired location on the screen, for example, a location that does not interfere with the subject image displayed through.

(Modification 3)
In the second embodiment, the digital camera 1 is described based on an example in which the front side includes the taking lens 2-1 and the CCD 23-1, and the back side includes the taking lens 2-2 and the CCD 23-2. However, according to the second and second modified examples of the second and second embodiments, the digital camera 1 has a photographing lens 2-1 and CCD-23-1, and a photographing lens 2-2 and CCD- 23-2 is also applicable.
In such a case, in the simultaneous photographing mode, the optical images captured by the photographing lens 2-1 and the photographing lens 2-2 on the front side are combined and displayed through. Further, since the imaging unit 2-1 or the imaging unit lens 2-2 operates as a sensor by the switch operation in step T2 in FIG. 5, the peripheral light source in front of the camera can be used efficiently.
In the camera shake prevention shooting mode, an image captured by one imaging unit is enlarged and displayed in a window. Since the movement of the enlarged image is easy to detect, the image in the window can be used as an image for preventing blurring.

    As mentioned above, although several Example of this invention was described, it cannot be overemphasized that this invention is not limited to said each Example, A various deformation | transformation implementation is possible.

It is a figure which shows one Example of the external appearance structure of the digital camera to which this invention is applied. It is a figure which shows one Example of the electronic circuit structure of the digital camera of FIG. It is explanatory drawing of AWB (white balance) processing in a color process circuit. It is a flowchart for demonstrating operation | movement of the digital camera at the time of sensor imaging | photography mode. 6 is a flowchart for explaining the operation of the digital camera in the simultaneous photographing mode. It is a figure which shows the example of the synthesized image of the to-be-photographed image displayed on the monitoring state at the time of simultaneous imaging | photography mode, and a monitor side image. 6 is a flowchart for explaining an operation of the digital camera 1 in a camera shake prevention shooting mode. It is a figure which shows the example of the synthetic | combination image of the to-be-photographed image displayed on the monitoring state at the time of camera-shake prevention imaging | photography mode, and a monitor side image.

Explanation of symbols

1 Digital camera 7 Shutter key (Imaging instruction means)
8 Mode switch (Imaging mode selection means)
9 Menu key (Imaging mode selection means)
13 Display section (composite image display means)
20-1 Subject imaging unit (first imaging unit)
20-2 Monitor side imaging unit (second imaging unit)
29 color process circuit (signal conversion processing means)
31 DRAM (image storage memory)
32 Control unit (simultaneous photographing control means, image storage control means)
38 Storage memory (storage memory)
135 windows

Claims (3)

A first imaging unit that captures a front subject image and outputs a photoelectric conversion signal is arranged on the front, and a second imaging unit that captures a rear subject image and outputs a photoelectric conversion signal can be displayed on the back. In a digital camera with a display unit,
When photographing a front subject, the rear subject is enlarged and photographed by the rear imaging device, and the front subject is displayed on the monitor arranged on the rear, and the rear subject image enlarged in the monitor window is displayed. A digital camera characterized in that a camera shake situation can be emphasized and displayed by displaying a through image. The digital camera according to claim 1 , further comprising a simultaneous shooting mode in which the first imaging unit and the second imaging unit perform imaging at substantially the same time. A first imaging unit that captures a front subject image and outputs a photoelectric conversion signal is arranged on the front, and a second imaging unit that captures a rear subject image and outputs a photoelectric conversion signal can be displayed on the back. To the digital camera computer with the display unit,
When shooting a subject in front, a function to magnify and shoot the subject on the back with the image sensor on the back, a function to display the subject in front on a monitor placed on the back, and a back subject image enlarged to a window And a program for executing a through image display function.

Images