JP2008035307A - Information processor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress an increase in power consumption by outputting image data to a monitor without using a mass memory in an image pickup device capable of displaying the image data acquired by a CCD on the monitor. <P>SOLUTION: Image data subjected to resolution conversion is temporarily stored in a memory for work, and the image data is transferred according to a transfer mode between an indirect transfer mode for storing the image data stored in the memory for work in a line memory of a display control part and a direct transfer mode for directly storing the image data subjected to resolution conversion in a line memory of a display control means. About the direct transfer mode or the indirection transfer mode, the direct transfer mode is selected when the period of a vertical synchronizing signal of the CCD is the same as the period of a vertical synchronizing signal of the monitor, and the indirect transfer mode is selected when the periods are different. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an imaging apparatus capable of displaying a captured image acquired by an imaging element on a monitor.

  Many digital cameras having a monitor such as a liquid crystal display are widely used. Such a digital camera can display an image acquired by an image sensor such as a CCD as a through image on the monitor, and can cause the monitor to function as an electronic viewfinder.

In general, the number of image data acquired by the CCD is often different from the number of image data required for monitor display. Therefore, after the resolution conversion of the image data acquired by the CCD is performed, it is stored in the buffer memory. The image data is temporarily stored, and then the image data is output to the monitor (see Patent Documents 1 to 4).
JP-A-5-176213 Japanese Patent Laid-Open No. 10-13735 JP 10-336573 A JP 2001-197348 A

  However, the techniques described in Patent Documents 1 to 4 use a large-capacity memory in order to display image data acquired by the CCD on a monitor. For this reason, a large amount of drive current is required to drive the large-capacity memory, which increases the power consumption of the digital camera. Moreover, although the technique described in Patent Document 2 outputs image data acquired by a CCD directly to a monitor, it is necessary to control the output of the image data acquired by the CCD, which is necessary for the control. I had to arrange a control circuit.

  Accordingly, an object of the present invention is to suppress an increase in power consumption by outputting image data to a monitor without using a large-capacity memory in an imaging apparatus capable of displaying image data acquired by a CCD on the monitor.

  In order to solve the above problems, an imaging apparatus according to the present invention generates a charge signal by exposing a plurality of imaging elements arranged in a two-dimensional manner to the imaging elements in accordance with a vertical synchronization signal. Imaging control means for sequentially outputting the generated charge signal as image data for each line or a plurality of lines, and a plurality of first storage means for storing the output image data for at least one line. A resolution conversion means for converting the resolution of the image data using the first storage means; a second storage means capable of storing image data for a plurality of lines; and an image indicated by the image data on a display screen. In an imaging apparatus comprising display control means for displaying and third storage means for storing image data to be output to the display control means, an image subjected to resolution conversion by the resolution conversion means Data is temporarily stored in the second storage means, and the image data stored in the second storage means is stored in the third storage means in response to a request signal output from the display control means. The resolution conversion is performed according to any one of the indirect transfer mode and the direct transfer mode in which the image data subjected to the resolution conversion is directly stored in the third storage means without going through the second storage means. Transfer control means for transferring the processed image data to the third storage means, wherein the transfer control means transfers the direct transfer when the period of the vertical synchronization signal and the period of the vertical synchronization signal of the display screen are the same. The image data subjected to the resolution conversion according to the mode is transferred to the third storage means, and the image data subjected to the resolution conversion according to the indirect transfer mode is transferred when the period is different. It is characterized in that for transferring the serial third memory means.

  The image processing apparatus further includes electronic zoom means for cutting out a partial angle of view of the image data output from the imaging control means and performing electronic zoom processing, and the transfer control means transfers the image data subjected to the electronic zoom processing. In this case, even if the vertical synchronization signal of the image sensor and the vertical synchronization signal of the display screen are the same, the image data may be transferred to the third storage unit according to the indirect transfer mode. Good.

  Further, the imaging control means outputs the image data in accordance with any readout mode of an all-pixel readout mode for reading out all charge signals from the image sensor and a thinning-out readout mode for reading out some of the charge signals. And the transfer control means, when transferring the image data read out in the all-pixel read mode, the indirect indirect even if the vertical synchronizing signal of the image sensor and the vertical synchronizing signal of the display screen are the same. The image data may be transferred to the third storage unit according to a transfer mode.

  Further, the image processing apparatus further includes moving image processing means for generating moving image data based on the image data output from the imaging control means, and the transfer control means is configured to transmit a vertical synchronization signal of the image sensor when transferring the moving image data. Even if the vertical synchronizing signal of the display screen is the same, the image data may be transferred to the third storage means according to the indirect transfer mode.

  The display control means includes detection means for detecting whether or not the display screen scanning method is field scanning, and when the display screen display method is field scanning, Even if the vertical synchronizing signal of the display screen is the same, the transfer control means may transfer the image data subjected to the resolution conversion to the third storage means according to the indirect transfer mode. .

  In addition, the resolution conversion unit includes a spline interpolation processing unit that performs resolution conversion by spline interpolation on the image data output from the imaging control unit using the first storage unit, and is output from the imaging control unit. A plurality of fourth storage means capable of storing at least one line of image data, and linear interpolation for performing resolution conversion by linear interpolation on the image data output from the imaging control means using the fourth storage means Processing means, wherein the number of the first storage means is larger than the number of the fourth storage means, and when the transfer control means follows the direct transfer mode, the resolution conversion means is the spline interpolation processing means. When the resolution conversion is performed and the indirect transfer mode is followed, the resolution conversion means performs the solution by the linear interpolation processing means. It is also possible and performs degrees conversion.

  When the period of the vertical synchronizing signal of the image sensor and the period of the vertical synchronizing signal of the display screen are the same, the image data subjected to resolution conversion by the resolution converting means is directly stored in the third storing means without going through the second storing means. By doing so, it is not necessary to drive the second storage means, so that the power consumption of the imaging apparatus can be suppressed.

  Embodiments of the present invention will be described below with reference to the drawings.

[First Embodiment]
FIG. 1 is a block diagram illustrating an example of a functional configuration of the digital camera 100 according to the present embodiment. The photographic lens 1 is used to form a subject image on the imaging surface of the CCD 2, and is composed of a focus lens, a zoom lens, and the like. The CCD 2 has a photocathode in which a large number of light receiving elements are two-dimensionally arranged, and a subject image that has passed through the photographing lens 1 is formed on the photocathode and is subjected to photoelectric conversion. In front of the photocathode, a microlens array (not shown) for condensing light on each pixel and a color filter array (not shown) in which RGB filters are regularly arranged are arranged. Yes. The CCD 2 reads out one line of the charge signal accumulated for each pixel in synchronization with the vertical synchronization signal and the horizontal synchronization signal supplied from the CCD control unit 3 and outputs them as image data. In this embodiment, the image data is output from the CCD 2 line by line, but the output image data may be one line or more.

  The timing generator 4 generates a timing signal. The timing signal is output to the CCD control unit 3, the analog signal processing unit 5, etc., and the operation of the shutter button (not shown), the opening / closing of the shutter (not shown), the charge signal acquisition of the CCD 2, and the processing of the analog signal processing unit 5 are synchronized. Used for.

  The analog signal processing unit 5 includes a correlated double sampling circuit (CDS) that removes noise from the image data output from the CCD 2, an auto gain controller (AGC) that performs gain adjustment, and an A / D that converts the image data into digital data. A converter (ADC) is provided.

  The image processing unit 6 performs image quality correction processing such as gamma correction, sharpness correction, and contrast correction on the digital image data output from the analog signal processing unit 5, as well as Y data that is a luminance signal, and a blue color difference signal YC processing for converting the data into YC data consisting of Cb data that is and Cr data that is a red color difference signal is performed.

  The resolution conversion unit 7 performs resolution conversion processing for matching the resolution of the image data output from the image processing unit 6 with the resolution of the monitor 10 or the external monitor 21. FIG. 2 shows an example of a specific configuration of the resolution conversion unit 7. The resolution converter 7 includes a horizontal resolution converter 71, memory selectors 72 and 77, a first line memory 73, a second line memory 74, a third line memory 75, a fourth line memory 76, and a vertical resolution converter 78. Is done. The horizontal resolution conversion unit 71 performs horizontal resolution conversion on the image data for one line output from the image processing unit 6. The image data subjected to resolution conversion is sequentially stored in any of the first to fourth line memories selected by the memory selector 72.

  In this embodiment, the case where four line memories are provided will be described. However, if the period of the horizontal synchronizing signal of the CCD 2 is an integer multiple of the period of the horizontal synchronizing signal of the monitor 10, three line memories are used. It is possible to operate with. Further, when the period of the horizontal synchronizing signal of the monitor 10 is longer than twice the period of the horizontal synchronizing signal of the CCD 2, further line memory is required. However, these can be applied when the display target sections in the vertical direction of the CCD 2 and the monitor 10 are substantially the same. If there is a large difference in the display target sections, a line memory is further required.

  The image data stored in the first to fourth line memories is selected by the memory selector 77 and output to the vertical resolution conversion unit 78. The vertical resolution conversion unit 78 performs vertical resolution conversion.

  Returning to FIG. The image data that has undergone vertical resolution conversion by the vertical resolution converter 78 is output to the display controller 9 by the selector 8 or stored in the work memory 12 via the memory controller 11. The selection unit 8 outputs image data to either the display control unit 9 or the memory controller 11 in accordance with a control signal output from the CPU 16.

  The display control unit 9 displays the image data output from the selection unit 8 on the monitor 10 as a through image. FIG. 2 shows an example of a specific configuration of the display control unit 9. The display control unit 9 includes a fifth line memory 91, a sixth line memory 92, a memory selector 93, and a display processing unit 94. The fifth and sixth line memories store image data for one line output from the selection unit 8. The memory selector 93 selects either the fifth or sixth line memory and outputs the image data to the display processing unit 94. The display processing unit 94 converts the image data output from the memory selector 93 into, for example, a composite signal that combines a luminance (Y) signal and a color (C) signal into a single signal, and the monitor 10 or the external monitor 21. Output to.

  The monitor 10 is composed of a liquid crystal display or the like, and functions as an electronic viewfinder such as displaying a through image in the shooting mode, displaying a shot image immediately after shooting, playing a still image, moving image, and various settings in the playback mode. Displays the menu. The external monitor 21 is a cathode ray tube television, a liquid crystal television, a plasma television, a personal computer display, or the like.

  Returning to FIG. The memory controller 11 performs control for storing the image data output from the selection unit 8 in the work memory 12. In addition, the media control unit 13 performs transmission / reception control of the image data stored in the work memory 12. The work memory 12 temporarily stores the image data output from the memory controller 11, and is composed of a large capacity memory such as a DRAM. The media control unit 13 reads or writes image data or the like stored in the external recording medium 31.

  The operation unit 14 is a button, lever, switch, or the like necessary for operating the digital camera 100, and outputs an operation signal to the CPU 16 in accordance with a user operation.

  The compression / decompression processing unit 15 performs compression processing on the shadow image data by a compression method such as JPEG to generate compressed image data. Further, in the reproduction mode, decompression processing is performed on the compressed image data read from the external recording medium 31.

  The CPU 16 controls each part of the main body of the digital camera 100 in accordance with signals from the operation unit 14 and each functional block.

  Here, conventionally, the image data subjected to the resolution conversion in the resolution conversion unit 7 is temporarily stored in the work memory 12 and then stored in the work memory 12 in accordance with a line request signal or the like output from the display control unit 9. The image data was output to the display control unit 9. However, since the work memory 12 is a large-capacity memory such as a DRAM, a large amount of drive current is generated due to reading and writing of data, which causes an increase in power consumption of the digital camera 100.

  The reason why the image data is temporarily stored in the work memory 12 is that the period of the vertical synchronizing signal of the CCD 2 and the period of the vertical synchronizing signal of the monitor 10 are different. Therefore, if the period of the vertical synchronizing signal of the CCD 2 and the period of the vertical synchronizing signal of the monitor 10 are the same, the image data is not stored in the work memory 12 but directly in the fifth and sixth line memories of the display control unit 9. Display processing is possible even if it is transferred. Furthermore, since it is not necessary to use the work memory 12, power consumption can be suppressed.

  Hereinafter, when the image data output from the resolution converter 7 is directly transferred to the fifth and sixth line memories (direct transfer mode), the image data is stored in the work memory 12 and then transferred to the fifth and sixth line memories. The operation in the case (indirect transfer mode) will be described using a timing chart.

  FIG. 3 is a timing chart in the direct transfer mode when the number of vertical monitors 10 is greater than the number of vertical CCDs 2 and FIG. 4 is a timing chart in the direct transfer mode when the number of vertical CCDs 2 is greater than the number of vertical monitors 10.

  First, in response to the vertical synchronization signal on the CCD side, the capturing of the charge signal in the imaging effective area of the CCD 2 is started, and image data for one line from the CCD 2 is converted to the analog signal processing unit 5 in synchronization with the horizontal synchronization signal on the CCD side. Is output. The image data output from the CCD 2 is subjected to horizontal resolution conversion in the horizontal resolution conversion unit 71 of the resolution conversion unit 7 via the analog signal processing unit 5 and the image processing unit 6 and sequentially applied to the first to fourth line memories. Remembered.

  Then, when the image data is stored in the first line memory 73 and the second line memory 74, the image data for two lines is output to the vertical resolution conversion unit 78 and subjected to linear interpolation processing, thereby converting the resolution in the vertical direction. Is done. In this embodiment, linear interpolation is described as an example, but other interpolation processing such as spline interpolation may be used. However, when using spline interpolation, it is necessary to install more line memories in the resolution converter 7 than the number shown in FIG.

  Normally, the selection unit 8 outputs a weight signal to the vertical resolution conversion unit 78, and cancels this weight signal in response to the line request signal and the line number signal output from the display processing unit 94. When the weight signal is canceled, the vertical resolution conversion unit 78 outputs the image data to the selection unit 8. The image data is stored in the fifth or large 6-line memory via the selection unit 8.

  When the line request signal and the line number signal output from the display processing unit 94 are disabled, the selection unit 8 outputs a wait signal to the vertical resolution conversion unit 78 again. It should be noted that the display-side vertical synchronization signal is generated after the CCD-side vertical synchronization signal so that the selection unit 8 can accept the line request signal and the line number signal when the image data for two lines is ready. It is desirable.

  Next, the memory selector 93 alternately selects one of the fifth and sixth line memories, and the image data stored in the selected line memory is output to the display processing unit 94. The display processing unit 94 outputs image data to the monitor 10 in synchronization with the horizontal synchronization signal.

  FIG. 5 is a diagram showing a timing chart in the indirect transfer mode. When the period of the vertical synchronizing signal of the CCD 2 and the period of the vertical synchronizing signal of the monitor 10 are different, processing is performed in the indirect transfer mode.

  First, in response to the vertical synchronization signal on the CCD side, the capturing of the charge signal in the imaging effective area of the CCD 2 is started, and image data for one line from the CCD 2 is converted to the analog signal processing unit 5 in synchronization with the horizontal synchronization signal on the CCD side. Is output. The image data output from the CCD 2 is subjected to horizontal resolution conversion in the horizontal resolution conversion unit 71 of the resolution conversion unit 7 via the analog signal processing unit 5 and the image processing unit 6 and sequentially applied to the first to fourth line memories. Remembered.

  Then, when the image data is stored in the first line memory 73 and the second line memory 74, the image data for two lines is output to the vertical resolution conversion unit 78 and subjected to linear interpolation processing, thereby converting the resolution in the vertical direction. Is done.

  In the indirect transfer mode, no weight signal is output from the selection unit 8 to the vertical resolution conversion unit 78, and image data is sequentially output to the selection unit 8 when the resolution conversion is completed in the vertical resolution conversion unit 78. . The selection unit 8 assigns an address to the image data and outputs it to the memory controller 11. The memory controller 11 stores this image data in the work memory 12.

  Then, in response to the line request signal and the line number signal output from the display processing unit 94, the selection unit 8 reads the image data from the work memory 12 and sequentially outputs it to the fifth or sixth line memory. The memory selector 93 alternately selects either the fifth or sixth line memory, and the image data stored in the selected line memory is output to the display processing unit 94. The display processing unit 94 outputs image data to the monitor 10 in synchronization with the horizontal synchronization signal.

  The direct transfer mode or the indirect transfer mode is designated by outputting an instruction signal from the CPU 16 to the selection unit 8. In accordance with this instruction signal, the selection unit 8 directly transfers the image data stored in the resolution conversion unit 7 to the fifth and sixth line buffers of the display control unit 9 or transfers it to the work memory 12 via the memory controller 11. Remember.

  As described above, when the period of the vertical synchronizing signal of the CCD 2 and the period of the vertical synchronizing signal of the monitor 10 are the same, the image data subjected to resolution conversion by the resolution converting unit 7 is passed through the work memory 12. By storing the data directly in the line memory of the display control unit 9, the work memory 12 is not driven, so that power consumption can be suppressed.

[Second Embodiment]
In the first embodiment, the direct transfer mode has been described when the period of the vertical synchronization signal of the CCD 2 and the period of the vertical synchronization signal of the monitor 10 are the same, and the indirect transfer mode has been described when the period is different. In the second embodiment, a case will be described in which the mode is switched depending on whether the zoom state shifts to optical zoom or electronic zoom in addition to the above conditions. The functional block diagram of the digital camera 100 and the timing chart in the direct transfer mode and in the indirect transfer mode in this embodiment are the same as those shown in FIGS.

  The optical zoom is a method for performing zoom processing of a subject image by moving a zoom lens included in the photographing lens 1 in the optical axis direction. The electronic zoom is a method for performing zoom processing by cutting out a partial angle of view of image data. This is a zoom method. In the case of the optical zoom, there is no change in the reading area of the charge signal read from the CCD 2, but in the case of the electronic zoom, the reading area of the charge signal changes closer to the center in both the vertical and horizontal directions than the reading area of the optical zoom. That is, since the charge signal reading area in the CCD 2 becomes extremely small, a buffer for holding image data is required on the display side. Therefore, even if the period of the vertical synchronizing signal of the CCD 2 and the period of the vertical synchronizing signal of the monitor 10 are the same, the image data is transferred according to the indirect transfer mode when the zoom lens is located in the electronic zoom region.

  FIG. 6 is a flowchart illustrating a method of switching between the direct transfer mode and the indirect transfer mode according to the zoom state. First, when a zoom button pressing signal of the operation unit 14 is input to the CPU 16 (step S11; YES), the CPU 16 instructs to move the position of the zoom lens of the photographing lens 1 in conjunction with the pressing of the zoom button. Output a signal. Then, when the zoom button has been pressed, it is determined whether the zoom lens is located in the optical zoom area or the electronic zoom area (step S12). If the zoom lens is located in the electronic zoom area (step S12; YES), and the position of the zoom lens immediately before (for example, before pressing the zoom button) is in the optical zoom area (step S15; YES), the CPU 16 performs the transfer mode. Is switched from the direct transfer mode to the indirect transfer mode, and the instruction signal is output to the selection unit 8 (step S16). On the other hand, when the position of the zoom lens immediately before is the electronic zoom area (step S15; NO), the mode is not switched.

  In step S12, if the current zoom lens position is in the optical zoom area (step S12; NO) and the previous zoom lens position is in the electronic zoom area (step S13; YES), the CPU 16 transfers. The mode is switched from the indirect transfer mode to the direct transfer mode, and the instruction signal is output to the selection unit 8 (step S14). On the other hand, when the position of the zoom lens immediately before is the optical zoom region (step S13; NO), the mode is not switched.

[Third Embodiment]
In the third embodiment, when the period of the vertical synchronizing signal of the CCD 2 and the period of the vertical synchronizing signal of the monitor 10 are the same, the direct transfer mode is set, and when the period is different, the indirect transfer mode is set. A case will be described in which the mode is switched depending on whether the mode is the all-pixel readout mode or the thinning readout mode. The functional block diagram of the digital camera 100 and the timing chart in the direct transfer mode and in the indirect transfer mode in this embodiment are the same as those shown in FIGS.

  The all-pixel readout mode is a mode in which charge signals are read from all the image sensors that constitute the CCD 2. When it is necessary to acquire high-quality image data (for example, during photographing), the charge signal is read out in the all-pixel readout mode. The thinning readout mode is a mode in which a charge signal is read out from a part of the CCDs 2, and is a mode used when the image quality of image data does not matter, for example, when waiting for photographing (during display of a through image).

  When a through image is displayed during shooting standby, the normal frame rate is increased in order to smooth the movement of the image on the monitor 10. Accordingly, in the thinning readout mode, the period of the vertical synchronization signal of the monitor 10 and the period of the vertical synchronization signal of the CCD 2 can be made the same, so that image data can be transferred in the direct transfer mode.

  However, in the all-pixel reading mode, the period of the vertical synchronizing signal of the CCD 2 becomes longer than the period of the vertical synchronizing signal of the monitor 10. Therefore, the image data is transferred in the direct transfer mode in the thinning readout mode, and the image data is transferred in the indirect transfer mode when the captured image is acquired.

  FIG. 7 is a flowchart illustrating a method of switching between the direct transfer mode and the indirect transfer mode according to the charge signal reading mode of the CCD 2. First, when a shutter button pressing signal of the operation unit 14 is input to the CPU 16 (step S21; YES), the CPU 16 outputs an instruction signal for setting the all-pixel readout mode to the CCD control unit 3 (step S22). Thereby, image data is output from the CCD 2 in accordance with the all-pixel reading mode. Then, the CPU 16 switches the transfer mode from the direct transfer mode to the indirect transfer mode, and outputs the instruction signal to the selection unit 8 (step S23).

  When the photographing process ends (step S24; YES), the CPU 16 outputs an instruction signal for setting the thinning readout mode to the CCD controller 3 (step S25), and switches the transfer mode from the indirect transfer mode to the direct transfer mode. The instruction signal is output to the selection unit 8 (step S26).

[Fourth Embodiment]
In the fourth embodiment, when the period of the vertical synchronizing signal of the CCD 2 and the period of the vertical synchronizing signal of the monitor 10 are the same, the direct transfer mode is set, and when the period is different, the indirect transfer mode is set. A case where the mode is switched according to whether or not is will be described. The functional block diagram of the digital camera 100 and the timing chart in the direct transfer mode and in the indirect transfer mode in this embodiment are the same as those shown in FIGS.

  In recent years, many digital cameras that can shoot moving images in addition to still images have become widespread. At the time of moving image shooting standby (when displaying a through image), image data can be transferred in the direct transfer mode if the period of the vertical synchronizing signal of the CCD 2 and the period of the vertical synchronizing signal of the monitor 10 are the same. Since it is necessary to acquire high-quality image data, the all-pixel readout mode is set. Furthermore, since the image data obtained by moving image shooting is subjected to compression processing and recorded on the external recording medium 31, it is necessary to output the image data to the compression / decompression processing unit 15, and the compression / decompression processing unit 15 It is preferable that the image data is temporarily stored in the work memory 12 that can be accessed. Therefore, image data is transferred according to the direct transfer mode when waiting for moving image shooting, and image data is transferred according to the indirect transfer mode during moving image shooting.

  FIG. 8 is a flowchart illustrating a method of switching between the direct transfer mode and the indirect transfer mode according to moving image shooting. First, the moving image shooting mode is selected by the mode lever of the operation unit 14 (step S31; YES), and when a recording start button pressing signal is further input to the CPU 16 (step S32; YES), the CPU 16 directly transfers the transfer mode. The mode is switched to the indirect transfer mode, and the instruction signal is output to the selection unit 8 (step S33).

  When the moving image shooting is completed (step S34; YES), the CPU 16 switches the transfer mode from the indirect transfer mode to the direct transfer mode and outputs the instruction signal to the selection unit 8 (step S35).

[Fifth Embodiment]
In the fifth embodiment, when the period of the vertical synchronizing signal of the CCD 2 and the period of the vertical synchronizing signal of the monitor 10 are the same, the direct transfer mode is set, and when the period is different, the indirect transfer mode is set. A case will be described in which the mode is switched depending on whether the scanning method of the display device for displaying the displayed image is field scanning. The functional block diagram of the digital camera 100 and the timing chart in the direct transfer mode and in the indirect transfer mode in this embodiment are the same as those shown in FIGS.

  In recent years, digital cameras that have an external output terminal capable of transmitting image data to the external monitor 21 and can display a through image on the external monitor 21 have been widely used. Since the CCD 2 generally reads out in units of frames, the resolution in the vertical direction is impaired in a display device in which the external monitor 21 displays an image by field scanning such as SDTV (Standard Definition Television). Therefore, if the display device for displaying a through image is a field scan, the image data is transferred according to the indirect transfer mode, and if the display device is a frame scan such as a liquid crystal display or HDTV (High Definition Television), it is directly transferred. The image data is transferred according to the mode.

  FIG. 9 is a flowchart illustrating a method of switching between the direct transfer mode and the indirect transfer mode according to the scanning method of the display device used for through image display. First, when the display control unit 9 detects the connection between the external output terminal and the external monitor 21 (step S41; YES), the display control unit 9 determines the scanning method of the external monitor 21. When the scanning method of the external monitor 21 is field scanning (step S42; YES) and the direct transfer mode is detected before switching is detected (step S43; YES), the CPU 16 changes the transfer mode from the direct transfer mode to the indirect transfer mode. Switching is performed, and the instruction signal is output to the selection unit 8 (step S44). If it is in the indirect transfer mode before the detection (step S43; NO), the CPU 16 does not switch the transfer mode.

  On the other hand, when the scanning method of the connected external monitor 21 is not field scanning (step S42; NO) and the indirect transfer mode is before detection of switching (step S45; YES), the CPU 16 sets the transfer mode to the indirect transfer mode. Is switched to the direct transfer mode, and the instruction signal is output to the selector 8 (step S46). If it is the direct transfer mode before the detection (step S45; NO), the CPU 16 does not switch the transfer mode.

[Sixth Embodiment]
In the sixth embodiment, when resolution conversion is performed, a case where spline interpolation is used in the direct transfer mode and linear interpolation is used in the indirect transfer mode will be described. FIG. 10 is a block diagram showing a part of the functional configuration of the digital camera 200 in the present embodiment. The same functional elements as those in the block diagram of the digital camera 100 shown in FIG.

  The resolution conversion unit 17 includes a linear interpolation processing unit 171 and a spline interpolation processing unit 172. The linear interpolation processing unit 171 performs resolution conversion by linear interpolation, and includes, for example, four line memories 73 to 74 as shown in FIG. The spline interpolation processing unit 172 performs resolution conversion by spline interpolation, and has more line memories than the line memory included in the linear interpolation processing unit 171 in order to correct distortion. Since spline interpolation can produce higher resolution image quality than linear interpolation, it is mainly used for resolution conversion of image data for recording.

  That is, since the spline interpolation processing unit 172 has more line memories than the linear interpolation processing unit 171, image data can be buffered for a longer time. Therefore, in the direct transfer mode, image data can be transferred smoothly by using the line memory of the spline interpolation processing unit 172. On the other hand, in the indirect transfer mode, the resolution-converted image data only needs to be sequentially stored in the work memory 12, and it is not necessary to buffer the image data for a long time in the resolution conversion unit 17, so the linear interpolation processing unit 171 is used. The resolution conversion process may be performed.

Functional block diagram of digital camera Functional block diagram of resolution converter and display controller Timing chart in direct transfer mode Timing chart in direct transfer mode Timing chart in indirect transfer mode The figure which showed the flow of the transfer mode switching in 2nd Embodiment The figure which showed the flow of the transfer mode switching in 3rd Embodiment The figure which showed the flow of the transfer mode switching in 4th Embodiment The figure which showed the flow of the transfer mode switching in 5th Embodiment Functional block diagram of a digital camera according to the sixth embodiment

Explanation of symbols

100, 200 Digital camera 1 Shooting lens 2 CCD
3 CCD control unit 4 Timing generator 5 Analog signal processing unit 6 Image processing unit 7, 17 Resolution conversion unit 171 Linear interpolation processing unit 172 Spline interpolation processing unit 8 Selection unit 9 Display control unit 10 Monitor 11 Memory controller 12 Work memory 13 Media Control unit 14 Operation unit 15 Compression / decompression processing unit 16 CPU
21 External monitor 31 External recording media

Claims (6)

A plurality of image pickup devices arranged in a two-dimensional manner and the image pickup device are exposed according to a vertical synchronization signal to generate a charge signal, and the generated charge signal is used as image data for one line at a time. Or, it has an imaging control means for sequentially outputting a plurality of lines and a plurality of first storage means for storing the output image data for at least one line, and the resolution of the image data using the first storage means Resolution conversion means for performing conversion, second storage means capable of storing image data for a plurality of lines, display control means for displaying an image indicated by the image data on a display screen, and image data output to the display control means In an imaging device comprising third storage means for storing
The image data that has undergone resolution conversion by the resolution conversion unit is temporarily stored in the second storage unit, and the image data stored in the second storage unit is used as a request signal output from the display control unit. An indirect transfer mode in which the third storage means is responsively stored, and a direct transfer mode in which the resolution-converted image data is directly stored in the third storage means without going through the second storage means. Further comprising transfer control means for transferring the image data subjected to the resolution conversion according to any transfer mode to the third storage means;
The transfer control means transfers the image data subjected to the resolution conversion according to the direct transfer mode to the third storage means when the period of the vertical synchronization signal and the period of the vertical synchronization signal of the display screen are the same. When the period is different, the imaging apparatus transfers the image data subjected to the resolution conversion according to the indirect transfer mode to the third storage means. Further comprising electronic zoom means for cutting out a partial angle of view of the image data output from the imaging control means and performing electronic zoom processing;
When transferring the image data on which the electronic zoom processing has been performed, the transfer control unit is configured to perform the indirect transfer mode even if the vertical synchronization signal of the image sensor and the vertical synchronization signal of the display screen are the same. The image pickup apparatus according to claim 1, wherein the image data is transferred to the third storage unit. The imaging control means outputs the image data in accordance with any readout mode of an all-pixel readout mode for reading out all charge signals from the imaging device and a thinning-out readout mode for reading out some of the charge signals.
When transferring the image data read in the all-pixel reading mode, the transfer control means is configured to transfer the image data even if the vertical synchronization signal of the image sensor and the vertical synchronization signal of the display screen are the same. The image pickup apparatus according to claim 1, wherein the image data is transferred to the third storage unit according to the above. A moving image processing unit for generating moving image data based on the image data output from the imaging control unit;
When transferring the moving image data, the transfer control means transfers the image data according to the indirect transfer mode even if the vertical synchronization signal of the image sensor and the vertical synchronization signal of the display screen are the same. The imaging apparatus according to claim 1, wherein the imaging apparatus is transferred to a storage unit. The display control means has detection means for detecting whether or not the scanning method of the display screen is field scanning,
When the display method of the display screen is field scanning, the transfer control means performs the resolution conversion according to the indirect transfer mode even if the vertical synchronization signal of the image sensor and the vertical synchronization signal of the display screen are the same. The imaging apparatus according to claim 1, wherein the image data transferred is transferred to the third storage unit. The resolution conversion means includes a spline interpolation processing means for performing resolution conversion by spline interpolation on image data output from the imaging control means using the first storage means, and image data output from the imaging control means. A plurality of fourth storage means capable of storing at least one line, and linear interpolation processing means for performing resolution conversion by linear interpolation on the image data output from the imaging control means using the fourth storage means And further having
The number of the first storage means is larger than the number of the fourth storage means,
When the transfer control means follows the direct transfer mode, the resolution conversion means performs the resolution conversion by the spline interpolation processing means, and when according to the indirect transfer mode, the resolution conversion means converts the resolution conversion by the linear interpolation processing means. The imaging apparatus according to claim 1, wherein the imaging apparatus performs the following.

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