JP5370662B2 - Imaging device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an imaging apparatus implementing a live view as a high definition finder while reducing power consumption. <P>SOLUTION: An imaging apparatus is equipped with: an imaging means which images a subject based on an imaging frame rate to capture image data; an interpolation image data generating means for generating interpolation image data between imaging frames from the image data; and a display means for displaying the image data or displaying the image data and the interpolation image data based on a display frame rate. When the imaging frame rate is set lower than the display frame rate and predetermined conditions are satisfied, the display means displays the image data and the interpolation image data and when the predetermined conditions are not satisfied, the display means displays the image data. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an imaging apparatus with reduced power consumption.

  In recent digital cameras, a viewfinder that determines a composition by determining a shooting range is not an optical type, but a live view using an image monitor on the back is the mainstream, and is known as a function unique to a digital camera.

In addition, the digital camera is configured to use the power of the battery mounted therein, and when the power consumption increases, the number of shootable images decreases.
For this reason, in order to effectively use the battery power and increase the number of images that can be shot, it is necessary to reduce the power consumption. In particular, it is desired to reduce the power consumption during live view.

  Therefore, in Patent Document 1, when the photographer performs the shooting operation while viewing the live view, the frame rate of the display unit is set high, and when the shooting operation is not performed, the frame rate of the display unit is set low. Thus, a digital camera that reduces power consumption is disclosed. Further, it is disclosed that the frame rate is reduced according to the remaining battery level, or the frame rate is reduced according to the exposure time.

  By the way, the lens unit that integrates the photographic lens and the solid-state image sensor can be attached to and detached from the camera body unit, so that the solid-state image sensor is not exposed when the photographic lens is replaced, and dust adheres to the imaging surface of the solid-state image sensor. An imaging system that prevents the above is known. In this imaging system, image signals and control signals are transmitted / received to / from each other through a transmission path in which a lens unit and a camera body unit are electrically connected at a contact point.

In such an imaging system, a live view on a liquid crystal monitor in the camera body unit is also used as a viewfinder, and solid-state imaging is used to display captured images on a liquid crystal monitor or record them on a memory card. The image data acquired by the element is transferred from the lens unit to the camera body unit, but there is a problem that the power consumption of the transmission path is large.
More specifically, when such a configuration is adopted, there is a problem that the amount of data transmitted between the lens unit and the camera body unit must be within the bus width of the transmission path. In other words, when the resolution of the solid-state imaging device of the lens unit increases, the lens unit compresses image data in advance so that the amount of data that must be transmitted between the lens unit and the camera body unit falls within the bus width of the transmission path. Preferably, it is necessary to reduce the amount of data communication between units. There is a similar problem in the case of moving image shooting.

For these reasons, in an imaging system in which a photographic lens and a solid-state imaging device are integrated and this lens unit can be attached to and detached from the camera body unit, image data is compressed or thinned by the lens unit, and the data communication amount between the units is reduced. The technology to reduce is researched and developed.
For example, in Patent Document 2, for the purpose of saving power, imaging that suppresses power consumption required for data transfer is performed by transferring thinned image data obtained by thinning pixels with a large amount of data to a main unit with a lens unit. A system is disclosed.
Further, in Patent Document 3, in order to greatly reduce the size of the frame buffer memory included in the camera module, the image data is compressed by the camera module, and the compression of the image data is performed in units of several lines of the image. A technique for performing transmission in the order of (First In First Out) and transmitting it to a host module is disclosed.

  However, in the digital camera described in Patent Document 1, although the power consumption is reduced due to a decrease in the frame rate (for example, 15 fps), the live view is not smooth and is compared with a general television image (30 to 60 fps). It becomes a live view to be crazy. The frame rate of the digital camera may greatly affect the operability depending on the shooting scene.For example, if the frame rate is low when shooting a moving subject, the composition will be determined because the live view cannot follow the movement of the subject. However, there is a problem that a photo opportunity is missed. Alternatively, in the digital camera described in Patent Document 1, if the frame rate is set to be equivalent to that of a general television image (30 to 60 fps), the power consumption cannot be reduced sufficiently, and the number of images that can be shot decreases. There was a problem of doing.

  Accordingly, a first object of the present invention is to provide an imaging apparatus capable of realizing a live view as a high-quality finder while reducing power consumption.

  In the techniques described in Patent Document 2 and Patent Document 3, when image data of about several tens to 60 frames per second is sent from the lens unit to the camera body unit one second like a live view, the camera body The unit performs decompression, image processing, and live view display processing for all these image data at the transmission timing from the lens unit, so it is necessary to match the drive frequency of the transmission path to that, and the image in the camera body unit There is a problem in that the processing timing needs to be matched with the processing timing, and as a result, the burden on the main unit is increased, so that the power consumption cannot be reduced sufficiently.

  Therefore, the present invention provides an imaging apparatus capable of realizing a live view as a high-quality finder while reducing power consumption even in the case of a camera system in which a lens unit having an imaging element is detachable from a main unit. It is a second subject to provide

In order to solve the above problems, an imaging apparatus according to the present invention specifically has the technical features described in the following (1) to (3) .
(1): An imaging unit that images a subject based on an imaging frame rate and acquires image data; an interpolation image data generation unit that generates interpolation image data between imaging frames from the image data; and the image data, Or display means for displaying the image data and the interpolated image data based on a display frame rate, wherein the display means has a predetermined condition when the imaging frame rate is set lower than the display frame rate. If the image data and the interpolated image data are satisfied, the image data is displayed if the predetermined condition is not satisfied, and includes an optical or electronic focal length changing means, and the display means , especially to display the image data and the interpolated image data when the focal length changing means has changed the focal length An imaging device according to.
(2): An imaging unit that images a subject based on an imaging frame rate and acquires image data; an interpolation image data generation unit that generates interpolation image data between imaging frames from the image data; and the image data, Or display means for displaying the image data and the interpolated image data based on a display frame rate, wherein the display means has a predetermined condition when the imaging frame rate is set lower than the display frame rate. Level level means for displaying the image data and the interpolated image data when satisfying the condition, displaying the image data when not satisfying a predetermined condition, and detecting whether or not the imaging device is horizontal And the display means displays the image data and the interpolated image data while the level means is operating. A.
(3) : a lens unit having the imaging unit and a main unit that detachably holds the lens unit, wherein the lens unit transmits the image data to the main unit, The imaging apparatus according to (1) or (2) , further including an interpolation image data generation unit and the display unit.

  According to the present invention, it is possible to provide an imaging apparatus capable of realizing a live view as a high-quality finder while reducing power consumption.

1 is a schematic front view showing a configuration of a digital camera which is a first embodiment of an imaging apparatus according to the present invention. 1 is a schematic rear view illustrating a configuration of a digital camera which is a first embodiment of an imaging apparatus according to the present invention. It is a block diagram which shows the structure of the control system of the digital camera which is 1st Embodiment of the imaging device which concerns on this invention. It is a conceptual diagram of the motion vector detection part in the digital camera which is 1st Embodiment of the imaging device which concerns on this invention. It is a chart figure which shows the timing chart of the live view when the high frame process is not performed in the conventional digital camera. It is a chart figure which shows the timing chart of the live view when the high frame process is performed in the digital camera which is 1st Embodiment of the imaging device which concerns on this invention. 3 is a flowchart of the first embodiment. It is a conceptual diagram for demonstrating determining a composition after focusing on a to-be-photographed object. 10 is a flowchart of Example 2. It is a conceptual diagram for demonstrating the case where zoom is used. 10 is a flowchart of Example 3. 10 is a flowchart of Example 4. It is a conceptual diagram for demonstrating confirming a horizontal state using an electronic level function. 4 is a conceptual diagram of a setup menu displayed on the image monitor 9. FIG. It is a schematic external view which shows the structure of the digital camera which is 2nd Embodiment of the imaging device which concerns on this invention. It is a block diagram which shows the structure of the control system of the digital camera which is 2nd Embodiment of the imaging device which concerns on this invention. It is a chart figure which shows the timing chart of the live view when the high frame process is not performed in the conventional digital camera. It is a chart figure which shows the timing chart of the live view when the high frame process is performed in the digital camera which is 2nd Embodiment of the imaging device which concerns on this invention.

An imaging apparatus according to the present invention images an object based on an imaging frame rate, acquires image data, interpolation image data generation means for generating interpolated image data between imaging frames from the image data, Display means for displaying the image data or the image data and the interpolated image data based on a display frame rate, wherein the display means is configured such that the imaging frame rate is set lower than the display frame rate. The image data and the interpolated image data are displayed when a predetermined condition is satisfied, and the image data is displayed when the predetermined condition is not satisfied.
Next, the imaging device according to the present invention will be described in more detail.
Although the embodiments described below are preferred embodiments of the present invention, various technically preferable limitations are attached thereto, but the scope of the present invention is intended to limit the present invention in the following description. Unless otherwise described, the present invention is not limited to these embodiments.

[First Embodiment]
FIG. 1 is a schematic front view showing a configuration of a digital camera which is a first embodiment of an imaging apparatus according to the present invention.
This imaging device is a digital camera that receives light passing through a lens with a solid-state imaging device, converts an analog signal of the solid-state imaging device into a digital signal, and records the digital signal on a memory card.

  On the front surface (FIG. 1) of the digital camera body 30, “POWER button 1”, “shutter button 2”, “flash emission unit 3”, “AF auxiliary light / self-timer lamp 4”, “lens cover 5” ”,“ Microphone 6 ”,“ Speaker 7 ”, and“ Lens 8 ”.

FIG. 2 is a schematic rear view of the digital camera 30 shown in FIG.
On the rear surface of the digital camera 30 (FIG. 2), “image monitor 9”, “zoom lever (telephoto) / (wide angle) 10”, “mode switch 11”, “play button 12”, “ADJ. Button 13” , “Delete / Self-timer button 14”, “↑ / MODE button 15”, “→ / Quick review button 16”, “MENU / OK button 17”, “↓ / Macro button 18”, “← / Flash button 19” “DISP. Button 20”, “AV output terminal 21”, “USB terminal 22”, “tripod screw hole 23”, and “battery / card cover 24” are arranged.

  When the battery / card cover 24 is opened, a battery insertion portion and a card insertion portion are provided, and a battery and a memory card are loaded therein.

  The mode switch 11 is composed of a two-position slide switch, and the mode of the digital camera 30 can be set according to the position. Camera operations such as still image shooting and moving image shooting are performed after the mode switch 11 is switched. There are two modes of the digital camera 30: “scene mode” and “still image shooting mode”.

  "Still image shooting mode" is used when shooting still images. "Scene mode" is "Portrait mode", "Face mode", "Sport mode", "Distant view mode", "Night view mode", There are “high sensitivity mode”, “zoom macro mode”, “monochrome mode”, “sepia mode”, “oblique correction mode”, “character mode”, “movie shooting mode” and the like.

  The playback button 12 functions as a button for instructing the mode of the digital camera 30 to “playback mode”. When this button is pressed in the shooting mode, the last captured still image is displayed on the image monitor 9.

  The lens 8 is constituted by a retractable zoom lens. When the camera is turned on by the POWER button 1 and the mode of the camera is set to the shooting mode by the mode switch 11, the digital camera 30 It is paid out.

  The zoom lever (telephoto) / (wide angle) 10 is a three-position lever around the shutter button 2 and functions as a means for instructing the zoom of the lens 8. When the digital camera 30 operates the zoom lever (telephoto) / (wide angle) 10 in the shooting mode to the telephoto side, the lens 8 zooms to the telephoto side, and the zoom lever (telephoto) / (wide angle) 10 to the wide angle. When operated to the side, the lens 8 zooms to the wide-angle side and changes the focal length of the lens 8. In the playback mode, when the zoom lever (telephoto) / (wide angle) 10 is operated to the wide angle side, the image being reproduced is reduced and displayed, and when the zoom lever (telephoto) / (wide angle) 10 is operated to the telephoto side, playback is performed. The image inside is enlarged and the display magnification of the reproduced image is changed.

  The shutter button 2 is composed of a two-stage switch and can be operated halfway and fully. In the digital camera 30, the AE / AF is activated by half-pressing the shutter button 2, and the AWB is activated by performing the push-off operation, thereby executing photographing.

  The image monitor 9 is composed of a liquid crystal display capable of color display, and is used as an image display panel for displaying captured images in the playback mode, and as a user interface display panel for performing various setting operations. Used. In the shooting mode, a live view is displayed as necessary and used as a view angle confirmation finder.

  The “↑ / MODE button 15”, “→ / quick review button 16”, “↓ / macro button 18”, “← / flash button 19” function as direction indicating means for inputting instructions in four directions, up, down, left and right. For example, it is used for selecting menu items on a menu screen.

  The MENU / OK button 17 functions as a button (MENU button) for instructing transition from the normal screen to the menu screen in each mode, and also functions as a button (OK button) for instructing selection confirmation, execution of processing, and the like. To do.

  The DISP. Button 20 functions as a button for instructing to change the display state of the screen, such as switching between display / non-display of the mark on the image monitor 9. Each time this button is pressed in the shooting mode, the display is switched as follows: histogram display → grid guide display → no display → image monitor off → normal mark display → histogram display →. Each time this button is pressed in the playback mode, the display is switched from histogram display → highlight display → no display → normal mark display → histogram display →. This button also functions as a button for instructing to cancel the input operation or return to the previous operation state.

FIG. 3 shows a configuration example of a control system inside the digital camera 30.
The overall operation of the digital camera 30 is comprehensively controlled by a central processing unit (CPU 40).
The CPU 40 has an operation unit 41 (POWER button 1, shutter button 2, zoom lever (telephoto) / (wide angle) 10, mode switch 11, playback button 12, ADJ. Button 13, delete / self-timer button 14, ↑ / MODE button 15, → / Quick review button 16, MENU / OK button 17, ↓ / macro button 18, ← / flash button 19, DISP. Overall control of the camera 30 is performed.

  A flash ROM 58 connected to the CPU 40 via the bus stores a digital camera 30 that stores a control program 90 executed by the CPU 40, various data necessary for control, user setting information, and the like (for example, camera adjustment data 91 and camera setting data 92). Stores various setting information related to the operation of.

The memory (SDRAM 54) is used as a temporary storage area for calculation work areas of the CPU 40, image data (Raw-RGB image data 55, YUV image data 56, compression / expansion image data 57), and the like.
The lens barrel unit 100 includes a zoom lens 81 that captures an optical image of a subject, a focus lens 82, a lens driving unit 86 that controls them, an aperture 83, an aperture driving unit 87 that controls them, a mechanical shutter 84, and a shutter drive that controls a mechanical shutter. Part 88.

  The lens driving unit 86, the aperture driving unit 87, and the shutter driving unit 88 are driven and controlled by a driving command from the CPU 40.

  When the power source of the digital camera 30 is turned on, the control program is loaded into the memory (SDRAM 54), and the CPU 40 controls the operation of each part of the apparatus according to the control program. At the same time, data and the like necessary for control are temporarily stored in the memory (SDRAM 54).

  Since the flash ROM 58 is a rewritable semi-nonvolatile memory, the control program, various data necessary for control, and user setting information can be changed, and the function can be easily upgraded.

  The digital camera 30 is set to the shooting mode by setting the mode switch 11 to the shooting position, and shooting is possible. Then, when the shooting mode is set, the lens 8 is extended to enter a shooting standby state.

  Under this photographing mode, the subject light that has passed through the lens 8 forms an image on the light receiving surface of the solid-state imaging device via the diaphragm 83.

  The solid-state imaging device is composed of a CCD 85, and on its light receiving surface, red (R), green (G), and blue (B) color filters arranged in a predetermined arrangement structure (Bayer, G stripe, etc.). A number of photodiodes (light receiving elements) are two-dimensionally arranged via

  The subject light that has passed through the lens 8 is received by each photodiode and converted into a signal charge in an amount corresponding to the amount of incident light.

  The signal charge accumulated in each photodiode is sequentially read out as a voltage signal (image signal) corresponding to the signal charge based on the drive pulse supplied from the timing generator (TG89) and is read to the analog processing unit (CDS / AMP42). Added.

  The analog processing unit (CDS / AMP42) samples and holds the input RGB signal for each pixel (correlated double sampling processing), amplifies it, and outputs it to the A / D converter 43.

  The A / D converter 43 converts the analog RGB signal output from the analog processing unit (CDS / AMP 42) into a digital RGB signal, and outputs the digital RGB signal. The digital RGB signal output from the A / D converter 43 is Then, it is taken into the memory (SDRAM 54) as Raw-RGB image data via the sensor input control unit 44.

  The image signal processing unit 46 processes the Raw-RGB image data 55 captured in the memory 54 in accordance with a command from the CPU 40, converts it into a luminance signal (Y signal) and a color difference signal (Cr, Cb signal), and YUV image data 56. Is generated.

  That is, the image signal processing unit 46 includes a synchronization circuit (a processing circuit that converts a color signal into a simultaneous expression by interpolating a spatial shift of the color signal associated with the color filter array of the single CCD), and a white balance correction circuit. Functions as an image processing means including a gamma correction circuit, a contour correction circuit, a luminance / color difference signal generation circuit, and the like. And a color difference signal (luminance / color difference signal). The generated luminance / color difference signal is stored in the memory (SDRAM 54) as YUV image data 56.

  When outputting a captured image to the image monitor 9, YUV image data 56 is sent from the memory (SDRAM 54) to the OSDMIX unit 48.

  The OSDMIX unit 48 combines the luminance / color difference signals of the input YUV image data 56 by superimposing on-screen display data such as characters and graphics, and outputs them to the video encoder 65 and the image monitor signal processing unit 49. As a result, required shooting information and the like are displayed superimposed on the image data.

  The video encoder 65 converts the luminance / color difference signal of the input YUV image data 56 into a display digital display output signal (for example, NTSC color composite video signal), and the D / A converter 66 performs digital display output. Convert the signal to an analog video output signal.

  The video AMP 67 performs 75Ω impedance conversion on the analog video signal output from the D / A converter 66 and outputs the analog video signal to the AV output terminal 21 for connection to an external display device such as a television. As a result, the image captured by the CCD 85 is displayed on an external display device such as a television.

  On the other hand, the image monitor signal processing unit 49 converts the luminance / color difference signal of the input YUV image data 56 into an RGB signal which is an input signal format of the image monitor 9 and outputs the RGB signal to the image monitor 9. As a result, the image captured by the CCD 85 is displayed on the image monitor 9.

  The image signal is periodically taken from the CCD 85, the YUV image data 56 in the memory (SDRAM 54) is periodically rewritten by the luminance / color difference signal generated from the image signal, and output to the image monitor 9 and the AV output terminal 21. Thus, an image captured by the CCD 85 is displayed in real time. The photographer can confirm the shooting angle of view by viewing the image (live view) displayed in real time on the image monitor 9.

  Shooting is performed by pressing the shutter button 2. Prior to photographing, when the photographer needs to adjust the angle of view, the photographer operates the zoom lever (telephoto) / (wide angle) 10 to zoom the zoom lens 81 and adjust the angle of view.

  When the shutter button 2 is half-pressed, an R1 ON signal is input to the CPU 40, and the CPU 40 performs AE / AF processing.

  First, an image signal captured from the CCD 85 via the sensor input control unit 44 is input to the AF detection unit 51 and the AE / AWB detection unit 52.

  The AE / AWB detection unit 52 includes a circuit that divides one screen into a plurality of areas (for example, 16 × 16) and integrates R, G, and B signals for each divided area, and provides the integrated value to the CPU 40. .

  The CPU 40 detects the brightness of the subject (subject brightness) based on the integrated value obtained from the AE / AWB detection unit 52, and calculates an exposure value (shooting EV value) suitable for shooting. Then, an aperture value and a shutter speed are determined from the obtained photographing EV value and a predetermined program diagram, and an appropriate exposure amount is obtained by controlling the electronic shutter and the aperture drive unit 87 of the CCD 85 according to the determined aperture value and shutter speed.

  Further, the AE / AWB detection unit 52 calculates an average integrated value for each color of the R, G, and B signals for each divided area during automatic white balance adjustment, and provides the calculation result to the CPU 40. The CPU 40 obtains the ratio of R / G and B / G for each divided area from the obtained R accumulated value, B accumulated value, and G accumulated value, and obtains the calculated R / G and B / G values. The light source type is determined based on the distribution in the color space of R / G and B / G.

  Then, according to the white balance adjustment value suitable for the discriminated light source type, for example, the value of each ratio is approximately 1 (that is, the RGB integration ratio is R: G: B≈1: 1: 1 on one screen). As described above, the gain value (white balance correction value) for the R, G, and B signals of the white balance adjustment circuit is controlled to correct the signal of each color channel.

  The AF detection unit 51 includes a high-pass filter that passes only high-frequency components of the G signal, an absolute value processing unit, an AF area extraction unit that extracts a signal within a predetermined focus area (for example, the center of the screen), and an absolute value within the AF area. The CPU 40 is notified of the integrated value data obtained by the AF detection unit. The CPU 40 calculates a focus evaluation value (AF evaluation value) at a plurality of AF detection points while controlling the lens driving unit 86 to move the focus lens 82, and a lens position where the evaluation value is maximized is set as a focus position. decide. Then, the lens driving unit 86 is controlled so that the focus lens 82 moves to the obtained in-focus position.

  As described above, the AE / AF processing is performed by half-pressing the shutter button 2.

  Thereafter, when the photographer presses down the shutter button 2, an R2 ON signal is input to the CPU 40, and the CPU 40 starts photographing and recording processing. That is, the CPU 40 controls the aperture driving unit 87 to move the aperture 83 according to the aperture value determined based on the photometric result, and controls the shutter driving unit 88 to control the opening / closing operation of the mechanical shutter 84 according to the shutter speed value. The CCD 85 is exposed by controlling the exposure time of the CCD 85.

  The image signal output from the CCD 85 is taken into the memory (SDRAM 54) via the analog processing unit (CDS / AMP) 42, the A / D converter 43, and the sensor input control unit 44, and the luminance / After being converted into a color difference signal, it is stored as YUV image data 56 in a memory (SDRAM 54).

  The YUV image data 56 stored in the memory (SDRAM 54) is added to the compression / decompression processing unit 47, compressed according to a predetermined compression format (for example, JPEG format), and then stored again as compressed / decompressed image data in the memory (SDRAM 54). Then, the image file is in a predetermined image recording format (for example, Exif format) and then recorded on the memory card 29 (for example, an SD card) via the card control unit 50.

  The image recorded in the memory card 29 as described above can be reproduced and displayed on the image monitor 9 by pressing the (reproduce) button.

  When the mode of the digital camera 30 is set to the playback mode by pressing the (playback) button, the CPU 40 outputs a command to the card control unit 50 and causes the memory card 29 to read the last image file recorded.

  The compressed image data of the read image file is added to the compression / expansion processing unit 47 and expanded to an uncompressed luminance / color difference signal, and then the image monitor 9 is passed through the OSDMIX unit 48 and the image monitor signal processing unit 49. Is output. As a result, the image recorded on the memory card 29 is reproduced and displayed on the image monitor 9.

  In order to perform USB communication with an external device such as a personal computer, connection is made via the USB terminal 22, and the CPU 40 controls the USB control unit 59 to perform USB communication.

  Audio signal data such as shutter sound and operation sound is stored in the flash ROM 58, and the CPU 40 controls the audio signal processing unit 45 and outputs the audio data to the audio CODEC 51 via the audio signal processing unit 45.

  The audio CODEC 51 includes a microphone amplifier that amplifies the input audio signal and an audio amplifier for driving the speaker 7. The audio CODEC 51 includes a microphone 6 for inputting a sound signal by the photographer, and an audio signal. Is connected, so that an audio signal is output from the speaker 7.

FIG. 4 is a conceptual diagram of the motion vector detection unit.
The motion vector detection unit 53 in the present embodiment detects a motion vector of an image by a method for obtaining a motion vector by a block matching method.

  The motion vector detection unit 53 divides the images of the frames P1 and P2 serving as a reference for detecting the motion vector into L × L blocks (10 × 10 blocks in FIG. 4), and uses the luminance information in the blocks to generate the reference frame P1. The luminance difference between corresponding pixels between the rectangular area (reference block) centered on the block of interest b1 in FIG. 2 and the rectangular area (candidate block) in the current image P2 is obtained, and the sum thereof is obtained. The above process is repeated while moving the candidate block within the range of the L × L block (search area), and a candidate block b2 having the smallest sum of luminance differences in the search area is obtained, and this is used as a reference block as a matching area. The displacement of the position is taken as a motion vector.

  The high frame processing by the CPU 40 will be described. When the interpolation frame Pt is generated using the frames P1 and P2, the pixel values at the position (x, y) in each frame are set to f1 (x, y), f2 (x, y), ft (x, y), When the motion vector amount is MV = (dx, dy), the following equation (1) is established.

  f1 (x + dx, y + dy) = f2 (x, y) (1)

  Since the elapsed time between frames depends on the capture frame rate from the CCD (imaging frame rate; the number of imaging frames per unit time), and can be assumed to be a uniform linear motion between frames. 2).

  ft (x + dx / 2, y + dy / 2) = f2 (x, y) (2)

The CPU 40 obtains the interpolated image Pt by using the pixel value f2 of the frame P2 as the pixel value of the interpolated frame in accordance with the equation (2).
When the interpolated image Pt is obtained, an image is generated from the matched portion, and for the inconsistent region, attention is paid to the inconsistent region, and the motion vector is obtained again, thereby completing the interpolated image of the interpolated image Pt.
Further, the image data is assigned in accordance with the motion vector by assigning the image data to each pixel of the interpolated image Pt. Pixels to which image data has not been assigned are assigned from neighboring or adjacent frame pixels.

  In this way, a smooth display live view is realized by detecting a motion vector from a plurality of images, generating an interpolation frame in accordance with the amount of motion between the images, and displaying them on an image monitor.

  The live view process will be described with reference to FIGS. FIG. 5 shows processing according to the prior art that does not perform high frame processing, and FIG. 6 shows processing when high frame processing is performed.

  CCDVD is a vertical synchronization signal for driving the CCD 85 with a drive pulse given from the timing generator (TG 89). In this example, the TG 89 is driven so that a drive pulse is given to the CCD 85 at a timing of 1/15 seconds, and a digital RGB signal from the CCD 85 is output from the CCD 85 at a frame rate of 15 fps.

  DISPVD is a drive pulse given to the image monitor 9 and is a vertical synchronization signal for driving the image monitor 9. In this example, the image monitor signal processing unit 49 gives a drive pulse to the image monitor 9 at a timing of 1/30 second, and the image monitor signal processing unit 49 inputs the luminance / color difference signal of the YUV image data 56 to the image monitor 9. The RGB signal converted into the signal format is driven so as to be output to the image monitor 9 at a frame rate of 30 fps.

  P1, P2, P3, P4, and P5 are image data, voltage signal (image signal) in the CCD exposure process, Raw-RGB image data 55 in the image signal capture process from the CCD, YUV image data 56 in the image process, display In the processing, it is an RGB signal.

A case where the high frame processing of FIG. 5 is not performed will be described.
Timing T1 to T2: The CCD 85 is exposed for 1/15 seconds to obtain a voltage signal (image signal) of P1.

Timing T2 to T3: Image signal capture processing from the CCD 85 is performed for a period of 1/15 seconds, and Raw-RGB image data P1 is captured into the memory 54 via the sensor input control unit 44. At the same time, the CCD 85 is exposed to obtain a voltage signal (image signal) of P2.
As described above, the exposure process of the CCD 85 and the image signal capturing process are continuously performed in units of 1/15 seconds.

Next, a description will be given focusing on the steps up to the live view of the P1 image.
Timing T3 to T4: The image signal processing unit 46 processes the Raw-RGB image data P1 captured in the memory 54 to generate YUV image data P1.

  Timing T5 to T6: The image monitor signal processing unit 49 converts the YUV image data P1 into RGB signals, outputs the RGB signals to the image monitor 9, and displays the image data P1. The image signal processing unit 46 generates YUV image data P2 from the image data P2 as soon as the capturing process of the image data P2 is completed.

  The live view is realized by sequentially displaying the image data P2, P3,... On the image monitor.

  When the high frame processing is not performed as shown in FIG. 5, the display frame rate (the number of display frames per unit time) of the image monitor has a capacity of 30 fps, but the input image (P1, P2,...) Constrained by the frame rate, live view is actually performed at a frame rate of 15 fps.

Next, a case where the high frame processing in FIG. 6 is performed will be described.
Timing T11 to T12: The CCD 85 is exposed for 1/15 seconds to obtain a voltage signal (image signal) of P1.

  Timing T12 to T13: The capturing process of the image signal P1 from the CCD 85 is performed for a period of 1/15 seconds, and the Raw-RGB image data P1 is captured into the memory 54 via the sensor input control unit 44. At the same time, the CCD 85 is exposed to obtain a voltage signal (image signal) of P2.

  Timing T13 to T15: The capturing process of the image signal P2 from the CCD 85 is performed for a period of 1/15 seconds, and the Raw-RGB image data P2 is captured into the memory 54 via the sensor input control unit 44. At the same time, the CCD 85 is exposed to obtain a voltage signal (image signal) of P3. As described above, the exposure process of the CCD 85 and the image signal capturing process are continuously performed in units of 1/15 seconds.

  Next, a description will be given focusing on the steps up to the live view of the P1 image and the high frame processing.

  Timing T13 to T14: The image signal processing unit 46 processes the Raw-RGB image data P1 captured in the memory 54 to generate YUV image data P1.

  Timing T15 to T16: The image signal processing unit 46 processes the Raw-RGB image data P2 captured in the memory 54 to generate YUV image data P2.

  Timing T15 to T17: The image monitor signal processing unit 49 converts the YUV image data P1 into RGB signals, outputs the RGB signals to the image monitor 9, and displays the image data P1.

  Timing T16 to T17: The CPU 40 uses the YUV image data P1 and P2 to perform the motion vector detection process and the interpolation frame image generation process described above to generate the interpolation frame image data Pt1.

  Timing T17 to T18: The image monitor signal processing unit 49 converts the YUV image data Pt1 into RGB signals, outputs them to the image monitor, and displays them.

  The live view is realized by sequentially displaying the image data P2, Pt2, P3, Pt3... On the image monitor.

  When the high frame processing is performed as shown in FIG. 6, a live view is performed using the display frame rate of 30 fps of the image monitor without being restricted by the frame rate of the input image (P1, P2,...).

  In this way, it is possible to provide a live view as a high-quality finder while reducing power consumption.

Example 1
Example 1 for suitably implementing the digital camera according to the present embodiment described above will be described.
FIG. 7 shows a flowchart of the first embodiment. FIG. 8 is a conceptual diagram for explaining that the composition is determined after focusing on the subject.
In this embodiment, when the AE / AF processing is performed by half-pressing the shutter button 2, and when the background is to be taken while the subject is in focus, the camera is moved while the shutter button 2 is half-pressed. The period during which the composition is determined is considered as the period during which the photographer determines the composition (FIG. 8), and the high frame processing is performed only during the period from when the shutter button 2 is half-pressed until the shutter button is fully pressed (during framing). I did it.

  First, the camera is turned on, and a live view is displayed as necessary in the shooting mode. The live view immediately after power-on does not perform high frame in order to reduce power consumption. (Step S101)

  When the CPU 40 detects that the shutter button 2 is half-pressed, AE / AF processing is performed. Prior to that, the motion vector detection unit 53 is used to frame the live view (steps S102 and S103), and the AE / AF processing. Is done. (Step S104)

  After the AE / AF process is performed in step S104, the CPU 40 further detects whether or not the shutter button 2 is half-pressed (step S105). S101) If it is continued, it is detected whether or not the shutter button has been pressed. If the half-pressed state is continued, it is a period in which the camera is moved and the composition is determined while the shutter button 2 is half-pressed as shown in FIG. Continue to detect the shutter button. (Step S106)

  When the CPU 40 detects that the shutter button 2 is fully pressed in step S106, the CPU 40 starts photographing and recording processing, and the photographed image is recorded on the memory card 29. When the recording is finished, the live view does not perform high frame in order to reduce power consumption. (Step S107)

  As described above, by setting the high frame rate period from the half-press of the shutter button 2 until it is fully pressed, the power consumption by the high gray camera is minimized, and the live as a high-quality finder that does not impair the function as a camera. Provide a view.

(Example 2)
Example 2 in which the digital camera according to the present embodiment described above is preferably implemented will be described.
FIG. 9 shows a flowchart of the second embodiment. FIG. 10 is a conceptual diagram for explaining a case where zoom is used.
In this embodiment, when the photographer needs to adjust the angle of view, the photographer composes the period during which the angle of view is adjusted by operating the zoom lever (telephoto) / (wide angle) 10 and zooming the zoom lens. Considering that the period is to be determined (FIG. 10), high-frame processing is performed only during the zooming period (when the focal length changing means is changing the focal length) based on the operation of the zoom lever (telephoto) / (wide angle) 10. I made it.

In addition, when a zoom lens with a high magnification is mounted (for example, 28 mm to 200 mm in terms of a 35 mm camera equivalent), when the zoom lens 81 is telephoto, the focal length becomes large (the angle of view becomes narrow), so the live view is It becomes more susceptible to camera shake. Live view loses stability due to the vibration of camera shake, and the quality of the viewfinder decreases.
Therefore, when the focal length is larger than a certain threshold value (105 mm in terms of 35 mm camera equivalent in this embodiment), a high frame processing is performed so that the quality as a finder is not deteriorated.
Although there are two types of zoom levers, wide angle and telephoto, FIG. 9 illustrates only the wide angle side.

  First, the camera is turned on, and a live view is displayed as necessary in the shooting mode. The live view immediately after power-on does not perform high frame in order to reduce power consumption. (Step S201)

  When the CPU 40 detects that the zoom lever (telephoto) / (wide angle) 10 is turned to the telephoto position, the CPU 40 zooms the zoom lens 81 to the wide angle side, but prior to that, the motion vector detection unit 53 is used to perform live view. A high frame is formed (steps S202 and S203), and zooming is performed to the wide angle side. (Step S204)

The CPU 40 further detects whether or not the zoom lever (telephoto) / (wide angle) 10 continues to be rotated (step S205), and if it continues, the zoom lens 81 has reached the telephoto end. Whether or not is detected. (Step S206) If the zoom lens 81 has reached the telephoto end, zooming of the zoom lens is stopped (Step S207). Otherwise, the process returns to Step S205, and the zoom lever (telephoto) / (wide angle) 10 is released. Continue detection of whether or not
When the zoom lever (telephoto) / (wide angle) 10 is released in step S205, zooming of the zoom lens 81 is stopped.
(Step S207)

  The CPU 40 checks how many millimeters the focal length is after zooming of the zoom lens 81 is stopped. (Step S208) If the focal length is 105 mm or longer, the high-frame display of the live view is continued. If it is smaller than 105 mm, the process returns to step S201, and the live view displays the high frame in order to reduce power consumption. Do not change.

As described above, by setting the high frame rate period to the zoom lens zooming period and the period in which the focal length is large (the angle of view is narrow), the power consumption due to the high frame is minimized and the function as a camera is not impaired. Provides live view as a high-quality viewfinder.
In the second embodiment, the optical zoom is used, but the same applies to the digital zoom.

(Example 3)
Example 3 in which the above-described digital camera according to the present embodiment is preferably implemented will be described.
FIG. 11 shows a flowchart of the third embodiment.
In the present embodiment, when the photographer needs to bring the lens close to the subject and take a close-up shot, the photographer operates the ↓ / macro button 18 to execute the high frame processing when the macro shooting mode is set.

The macro shooting mode can be used for shooting a small subject because the shortest shooting distance that can be focused can be reduced (for example, 1 cm from the front of the lens) by further expanding the moving range of the focus lens compared to the non-macro mode. Can do.
At this time, since the depth of field becomes extremely shallow, the live view is easily affected by camera shake. Live view loses stability due to the vibration of camera shake, and the quality of the viewfinder decreases.
In view of this, the high frame processing is performed under the condition that the depth of field is shallow as in the macro shooting mode so that the quality of the finder is not deteriorated.

  First, the camera is turned on, and a live view is displayed as necessary in the shooting mode. The live view immediately after power-on does not perform high frame in order to reduce power consumption. (Step S301)

  When the CPU 40 detects that the ↓ / macro button 18 is pressed, it enters the macro shooting mode. Prior to that, the motion vector detection unit 53 is used to frame the live view (steps S302 and S303), and the macro shooting is performed. Enter mode. (Step S304)

  The CPU 40 detects whether or not the ↓ / macro button 18 is further pressed after S302 (step S305). If it is pressed, the high frame is finished and the normal shooting mode is returned (step S306).

  As described above, by setting the high frame rate period to the macro shooting mode period when the depth of field is shallow (when the focal length changing means is changing the focal length), the power consumption due to the high frame rate is minimized. Provide a live view as a high-quality viewfinder that does not impair the function of the camera.

Example 4
Example 4 in which the above-described digital camera according to the present embodiment is preferably implemented will be described.
FIG. 12 shows a flowchart of the fourth embodiment.
In this embodiment, the camera is equipped with an “electronic level” function that is convenient when it is desired to take a horizontal image such as when shooting a landscape or a building.
FIG. 13 is a conceptual diagram for explaining that the horizontal state is confirmed using the electronic level function. With this “electronic level” function, the horizontal state of the image can be confirmed by the horizontal indicator and level sound displayed on the image monitor 9.

The camera tilt uses a two-axis or more acceleration sensor built in the camera. This sensor is connected to the CPU 40, and the CPU 40 can detect the left-right tilt by detecting the sensor output. .
The biaxial acceleration sensor is a sensor that detects gravity. When the sensor is placed in the horizontal direction, the output is zero. When the sensor is tilted, gravity is applied to output a signal associated therewith. Therefore, by arranging the two so as to be orthogonal to each other, it can be used as an absolute tilt sensor that indicates how many times the tilt is made with respect to the horizontal plane.

  Further, in order to reduce the power consumption of the camera, an “image monitor power saving” function for reducing the power consumption of the backlight part of the liquid crystal display of the image monitor 9 having a large power consumption is installed.

  FIG. 14 is a conceptual diagram of a setup menu displayed on the image monitor 9. The “Image monitor power saving function” function can be set in the setup menu. When [Image monitor power saving] is set to [ON], the camera is not moved for about 5 seconds with the image monitor 9 turned on. The brightness of the image monitor 9 is reduced by reducing the brightness of the backlight unit to save power. In that case, move the camera or press any button to restore. Whether or not the camera has moved is detected by the “electronic level” function.

  In this embodiment, whether or not the camera has moved with the electronic level function is considered as a period during which the photographer decides the composition, and the high frame processing is performed only during the period when the camera is moving. .

  First, when the CPU 40 detects the movement of the camera by the electronic level (step S401), the CPU 40 displays a live view with a high frame using the motion vector detection unit 53 (step S402), and the image monitor power saving is turned off. (Step S403)

Next, when the CPU 40 is in a stationary state in which no camera movement is detected by the electronic level (step S404), the CPU 40 detects whether or not the stationary state has continued for 5 seconds (step S405), and 5 seconds have elapsed. In this case, image monitor power saving is turned on (step S406), and the high frame is terminated. (Step S407)
Needless to say, the time for detecting the stationary state is set to 5 seconds, which is only one aspect, and a desired time may be set, so that the user of the digital camera can set an arbitrary time. Also good.

  As described above, the high frame rate period is set to the time when the camera is not detected (period in which the level device is operating) detected by the electronic level function, that is, the period in which the photographer determines the composition. The live view is provided as a high-quality viewfinder that minimizes the power consumption caused by the camera and does not impair the camera function.

[Second Embodiment]
FIG. 15 is a schematic external view showing a configuration of a digital camera which is the second embodiment of the imaging apparatus according to the present invention.
In FIG. 15, the digital camera 103 includes a main body unit 102 and a lens unit 101 that can be attached to and detached from the main body unit 102. The digital camera 103 functions as a digital camera (imaging system) by integrating the lens unit 101 and the main body unit 102. The lens unit 101 is appropriately selected from various types by the user and attached to the main body unit 102. For example, a lens unit 104a (FIG. 15A) of a single focus lens or an optical zoom is mounted. There is a lens portion 104b (FIG. 15B).
Although illustration and description are omitted here, as in the first embodiment described above, in the digital camera according to this embodiment, the “POWER (power button) 1”, “shutter button 2”, “ A “flash light emitting unit 3”, “AF auxiliary light / self-timer lamp 4”, “lens cover 5”, “microphone 6”, “speaker 7”, and “lens 8” are arranged. Moreover, since the configuration of the back surface is the same as that of the first embodiment described above, illustration and description thereof are omitted.

Next, the configuration of a control system of a digital camera which is the second embodiment of the imaging apparatus according to the present invention will be described with reference to the block diagram shown in FIG. A part of the description overlapping with the first embodiment described above is partially omitted.
Each part of the lens unit is configured to control the overall operation by a central processing unit (CPU).
The lens CPU is connected to a flash ROM that records a control program executed by the lens CPU, setting information, and the like via a bus, and controls each part of the lens unit by reading the control program from the flash ROM.
The memory made up of the SDRAM is used as a calculation work area for the lens CPU and a temporary storage area for image data (Raw-RGB image data, YUV image data, compression / expansion image data, etc.).

The photographing lens includes a zoom lens and a focus lens, and a zoom lens, a focus lens, a diaphragm, and a shutter are disposed along the optical axis.
The zoom motor operates in conjunction with a zoom (wide angle) button and a zoom (telephoto) button, and moves the zoom lens to the wide angle side or the telephoto side.
The focus motor operates in conjunction with autofocus by half-pressing the shutter release button, and moves the focus lens to the close side or infinity side.
The iris motor operates in conjunction with automatic exposure by half-pressing the shutter release button, changes the aperture value by changing the aperture area of the aperture, and adjusts the amount of light incident from the photographing lens.
The shutter motor operates in conjunction with a shooting operation by fully depressing the shutter release button. Normally, the shutter motor is controlled to open the shutter to start CCD signal accumulation and shut off the light after the exposure (shutter) time has elapsed. Close the shutter.
The motor driver is connected to each motor. A motor driver connected to the lens CPU that comprehensively controls the lens unit via the bus transmits a drive pulse to each motor based on a control signal from the lens CPU. Each motor rotationally drives the rotating shaft in accordance with this drive pulse.

  Behind the photographic lens is a solid-state imaging device that forms an image of subject light that has passed through the photographic lens on a light-receiving surface and performs photoelectric conversion (the solid-state imaging device is composed of a CCD, and the light-receiving surface has a predetermined arrangement. (A large number of photodiodes (light receiving elements) are two-dimensionally arranged via red (R), green (G), and blue (B) color filters arranged in a structure (Bayer, G stripe, etc.)) Is arranged.

The subject light that has passed through the photographic lens is received by each photodiode of the CCD, and converted into signal charges in an amount corresponding to the amount of incident light. The signal charge accumulated in each photodiode is sequentially read out as a voltage signal (image signal) corresponding to the signal charge based on a driving pulse given from the timing generator (TG) under the control of the lens CPU. It is added to the analog processing unit (CDS / AMP).
The analog processing unit (CDS / AMP) performs sampling hold (correlated double sampling processing), amplifies, and outputs the input RGB signal for each pixel to the A / D converter.
The A / D converter converts the analog RGB signal output from the analog processing unit (CDS / AMP) into a digital RGB signal and outputs the digital RGB signal. The digital RGB signal is input to the sensor input control unit, and Raw- It is taken into the SDRAM as RGB image data.

The image signal processing unit processes the Raw-RGB image data captured in the SDRAM in accordance with a command from the lens CPU, converts it into a luminance signal (Y signal) and a color difference signal (Cr, Cb signal), and generates YUV image data. . This image signal processing unit includes a synchronization circuit (a processing circuit that interpolates a spatial shift of the color signal associated with the color filter array of the single CCD and converts the color signal into a simultaneous expression), a white balance correction circuit, a gamma correction It functions as an image processing means including a circuit, a contour correction circuit, a luminance / color difference signal generation circuit, and the like.
The compression / decompression processing unit compresses the YUV image data converted into the luminance / color difference signal by the image signal processing unit in accordance with a predetermined compression format (for example, JPEG format), and then stores it again as compressed / decompressed image data in the SDRAM.

The AF detection unit divides one screen into a plurality of areas (for example, 16 × 16), and passes a high frequency component of the G signal only for each divided area, an absolute value processing unit, a predetermined focus area (for example, The AF area extracting unit for cutting out the signal in the center of the screen) and the integrating unit for integrating the absolute value data in the AF area.
The integrated value data obtained by the AF detection unit is notified to the lens CPU. The lens CPU controls the focus motor via the motor driver, calculates a focus evaluation value (AF evaluation value) at a plurality of AF detection points while moving the focus lens, and focuses the lens position where the evaluation value is maximized. Determine as position.
Then, an autofocus (AF) operation is performed by controlling the focus motor so that the focus lens moves to the obtained in-focus position.

The AE / AWB detection unit includes a circuit that divides one screen into a plurality of areas (for example, 16 × 16) and integrates R, G, and B signals for each divided area, and provides the integrated value to the lens CPU. .
The lens CPU detects the brightness of the subject (subject brightness) based on the integrated value obtained from the AE / AWB detection unit, and calculates an exposure value (shooting EV value) suitable for shooting.
Then, an aperture value and a shutter speed are determined from the obtained shooting EV value and a predetermined program diagram, and an iris motor is driven through the electronic shutter and motor driver of the CCD according to the determined EV value, and an appropriate exposure amount is controlled by controlling the aperture. Thus, an automatic exposure (AE) operation is performed.

The AE / AWB detection unit calculates an average integrated value for each color of the R, G, and B signals for each divided area during automatic white balance adjustment, and provides the calculation result to the lens CPU.
The lens CPU obtains the ratio of R / G and B / G for each divided area from the obtained integrated value of R, integrated value of B, and integrated value of G, and calculates the R / G and B / G values obtained. The light source type is determined based on the distribution in the R / G and B / G color spaces.
Then, according to the white balance adjustment value suitable for the discriminated light source type, for example, the value of each ratio is approximately 1 (that is, the RGB integration ratio is R: G: B≈1: 1: 1 on one screen). As described above, by controlling the gain values (white balance correction values) for the R, G, and B signals of the white balance adjusting circuit and correcting the signals of the respective color channels, the auto white balance (AWB) operation is performed.

Also, a control serial I / F and an external bus I / F are connected to the bus.
The control serial I / F is connected to the main unit through an electrical contact provided at a connection portion (not shown) of the mount portion. This control serial I / F is configured to be capable of bidirectional communication, and receives the state of various buttons on the main unit from the main unit CPU, and transmits the current zoom lens position to the main unit CPU. Use when.
The external bus I / F is connected to the main unit via an electrical contact provided at a connection portion (not shown) of the mount portion. The external bus I / F is configured to allow one-way communication from the lens unit to the main unit, and is used when image data is transmitted to the main unit. For example, it has a higher transfer speed than the control serial I / F, such as a parallel I / F or LVDSI / F.

Each part of the main unit is configured to control the overall operation by a central processing unit (CPU). The main body CPU is connected to a flash ROM that records a control program executed by the main body CPU, setting information, and the like via a bus, and controls each part of the lens unit by reading the control program and camera setting data from the flash ROM. To do.
A memory composed of SDRAM is used as a calculation storage area for the main body CPU and a temporary storage area for image data (YUV image data, compression / decompression image data, etc.).

Also, a control serial I / F and an external bus I / F are connected to the bus.
The serial I / F for control is connected to the serial I / F of the lens unit via an electrical contact provided at a connection part (not shown) of the mount part, and various control information is transmitted between the main unit and the lens unit. Send and receive.
Similarly, the external bus I / F is connected to the external bus I / F of the lens unit via an electrical contact, receives image data transmitted from the lens unit, and takes it into the SDRAM.
The compression / decompression processing unit decompresses the compressed / decompressed image data captured in the SDRAM according to a predetermined compression format (for example, JPEG format), and then stores the decompressed image data in the SDRAM again as YUV image data data.

The image monitor signal processing unit converts the luminance / color difference signal of the input YUV image data into an RGB signal which is an input signal format of the image monitor, and outputs it to the image monitor.
As a result, an image captured by the CCD in the lens unit is displayed on the image monitor. The image signal from the CCD is periodically taken in by the lens unit to be converted into YUV image data, and the YUV image data is compressed, periodically sent to the main unit via the transmission path by the external bus I / F, and received by the main unit. The compressed / decompressed image data is expanded into YUV image data, and the YUV image data on the SDRAM is periodically rewritten and output to an image monitor to perform a live view in which an image captured by the CCD is displayed in real time. .
The photographer can check the angle of view by viewing the image (live view) displayed in real time on the image monitor.

The memory card control unit reads / writes an image file obtained by compressing / decompressing image data in a predetermined image recording format (for example, Exif format) with respect to a memory card (for example, an SD card) that can be attached to and detached from the main unit.
The flash light control unit emits a flash light by a strobe light emission signal transmitted from the main body CPU or the lens CPU.
The USB control unit performs USB communication in which an external device such as a personal computer is connected to the main unit via a USB terminal.
The detachable battery supplies power to a DC / DC converter (DC / DC). The DC / DC on the main unit side steps down or boosts the voltage of the battery to a predetermined voltage required for each part of the main unit. Further, the DC / DC on the lens unit side steps down or boosts the battery voltage to a predetermined voltage required for each part of the lens unit.
In the present embodiment, a motion vector detection unit similar to that in the first embodiment described above is provided.

  The live view process will be described with reference to FIGS. FIG. 17 shows processing according to the prior art that does not perform high frame processing, and FIG. 18 shows processing when high frame processing is performed.

  CCDVD is a driving pulse given from a timing generator (TG) in the lens unit, and is a vertical synchronizing signal for driving the CCD. In this example, the TG is driven such that a drive pulse is given to the CCD at a timing of 1/30 seconds, and a digital RGB signal from the CCD is output from the CCD at a frame rate of 30 fps.

DISPVD is a drive pulse given to the liquid crystal monitor in the main unit, and is a vertical synchronization signal for driving the liquid crystal monitor. In this example, the liquid crystal monitor signal processing unit gives a driving pulse to the liquid crystal monitor at a timing of 1/30 second, and the liquid crystal monitor signal processing unit converts the luminance / color difference signal of the YUV image data into the input signal format of the liquid crystal monitor. It is driven so that RGB signals are output to the liquid crystal monitor at a frame rate of 30 fps.
In this embodiment, DISPVD and CCDVD do not include a mechanism for synchronizing them with each other.

  P1 to P9 are image data. By each process of the timing chart, the image data is processed and output using the data from the previous process as input data, and becomes the input data of the next process. In the CCD exposure process, this image data is a voltage signal (image signal). In the image signal capture from the CCD and the YUV conversion process from Raw-RGB, the voltage signal is converted to Raw-RGB image data, and then the YUV image data and Become. All subsequent processes become YUV image data.

The case of the prior art in which the high frame processing in FIG. 17 is not performed will be described.
T1 to T2 period: CCD exposure is performed for 1/30 second to obtain a voltage signal (image signal) of P1.
T2 to T3 period: The image signal from the CCD is captured via the sensor input control unit, and at the same time, the captured Raw-RGB image data P1 is sent to the image signal processing unit, and the Raw-RGB image data P1 is processed. Then, YUV image data P1 is generated and stored in the SDRAM.
At this time, CCD exposure is also performed sequentially, and a voltage signal (image signal) of P2 is obtained. As described above, the CCD exposure processing and the image signal capturing processing are continuously performed in units of 1/30 seconds.

T3-T4 period: The P1 image is transferred from the lens unit to the main unit. The YUV image data in the SDRAM is subjected to JPEG compression at the compression / decompression processing unit of the lens unit. This compressed image data is transferred from the lens unit to the main unit using the transmission path via the external bus I / F between the lens unit and the main unit.
At this time, the compressed image data flows through the transmission path in units of 1/30 seconds, and the next image data P2 cannot be transmitted unless the image transmission time ends within 1/30 seconds. Therefore, a drive frequency for the transmission line that satisfies these requirements is required.
Next, the compressed image data transferred to the main unit is decompressed by the compression / decompression processing unit of the main unit, decompressed to YUV image data, and stored as YUV image data in the SDRAM.

Period T4 to T5: The liquid crystal monitor signal processing unit of the main unit converts the YUV image data stored in the SDRAM into an RGB signal, and outputs it to the liquid crystal monitor to display the image data.
Similarly, the live view is realized by repeating the above processing with the image data P2, P3,.

When the high frame processing is not performed as shown in FIG. 17, the display frame rate of the liquid crystal monitor has a performance of 30 fps, but the TG drive of the lens unit, the sensor input control unit, and the transmission path are once every 1/30 seconds. It is necessary to drive each control unit to satisfy this.
Since it is necessary to increase the drive frequency of the image sensor and the drive frequency of the transmission path, which occupy a large proportion of the power consumption, the power consumption also increases. In order to reduce the power consumption, it is most effective to reduce the drive frequency, or reduce the data amount of the transmission path to shorten the operation time.

Next, a case where the high frame processing in FIG. 18 is performed will be described.
In the case of a high frame, since the display frame rate is twice the capture frame rate, the CCD exposure process and the image signal capture process may be performed in units of 1/15 seconds. Is 1/15 seconds.

T1 to T3 period: The CCD is exposed for 1/15 seconds to obtain a voltage signal (image signal) of P1.
T3 to T5 period: The image signal from the CCD is captured via the sensor input control unit, and at the same time, the captured Raw-RGB image data P1 is sent to the image signal processing unit, and the Raw-RGB image data P1 is processed. Then, YUV image data P1 is generated and stored in the SDRAM.
At this time, CCD exposure is also performed sequentially, and a voltage signal (image signal) of P3 is obtained. Since the drive frequency of the CCD is halved compared with 30 fps, the power consumption is reduced, but the image signal capture time from the CCD is doubled.

Period T5 to T7: The P1 image is transferred from the lens unit to the main unit. The YUV image data in the SDRAM is subjected to JPEG compression at the compression / decompression processing unit of the lens unit. This compressed image data is transferred from the lens unit to the main unit using the transmission path via the external bus I / F between the lens unit and the main unit.
At this time, the compressed image data flows through the transmission path in units of 1/15 seconds. The image transmission time is in balance with the high frame processing described later, and if the operating frequency is halved compared to 30 fps, it takes time to display, and this is not very desirable. However, the operation time of the transmission line is ½ compared with 30 fps.
Next, the compressed image data transferred to the main unit is decompressed by the compression / decompression processing unit of the main unit, decompressed to YUV image data, and stored as YUV image data in the SDRAM.
At the same time, the image signal capturing process of the P3 image data from the CCD and the captured Raw-RGB image data P3 are sent to the image signal processing unit, and the Raw-RGB image data P3 is processed to generate YUV image data P3. And stored in the SDRAM.

Period T7 to T9: The P3 image is transferred from the lens unit to the main unit, and YUV image data P3 is obtained.
The main body CPU performs the motion vector detection process and the interpolation frame image generation process described above using the YUV image data P1 and P3, and generates the interpolation frame image data P2 ′.
The liquid crystal monitor signal processing unit of the main unit converts the YUV image data P1, P2 ′, P3 stored in the SDRAM into RGB signals, and sequentially outputs them to the liquid crystal monitor at the timing of DISPVD to display the image data.
Similarly, the live view is realized by repeating the above processing with the image data P5, P7.

When the high frame processing is performed as shown in FIG. 18, the frame rate of the input image (P1, P3, P5...) Is lowered, the CCD drive frequency is lowered, and the operation time of the transmission path is reduced. While reducing the power consumption by lowering, the display frame rate of the liquid crystal monitor can provide a live view of 30 fps by increasing the frame rate.
In the second embodiment described above, any of Examples 1 to 4 relating to the above-described high frame processing can be applied.

  The present invention has been described above by the preferred embodiments of the present invention. While the invention has been described with reference to specific embodiments, various modifications and changes may be made to the embodiments without departing from the broad spirit and scope of the invention as defined in the claims. Obviously you can.

DESCRIPTION OF SYMBOLS 1 POWER button 2 Shutter button 3 Flash light emission part 4 AF auxiliary light / self-timer lamp 5 Lens cover 6 Microphone 7 Speaker 8 Lens

JP 2004-15595 A JP 2007-110314 A WO 04/112396

Claims (3)

Imaging means for imaging a subject based on an imaging frame rate and acquiring image data;
Interpolated image data generating means for generating interpolated image data between imaging frames from the image data;
Display means for displaying the image data or the image data and the interpolated image data based on a display frame rate;
The display means, when the imaging frame rate is set lower than the display frame rate,
When the predetermined condition is satisfied, the image data and the interpolated image data are displayed,
When the predetermined condition is not satisfied, the image data is displayed ,
With optical or electronic focal length changing means,
The image pickup apparatus , wherein the display unit displays the image data and the interpolated image data when the focal length changing unit changes the focal length .   Imaging means for imaging a subject based on an imaging frame rate and acquiring image data;
  Interpolated image data generating means for generating interpolated image data between imaging frames from the image data;
  Display means for displaying the image data or the image data and the interpolated image data based on a display frame rate;
  The display means, when the imaging frame rate is set lower than the display frame rate,
When the predetermined condition is satisfied, the image data and the interpolated image data are displayed,
When the predetermined condition is not satisfied, the image data is displayed,
  Comprising level means for detecting whether the imaging device is horizontal;
  The image pickup apparatus, wherein the display means displays the image data and the interpolated image data while the level device is operating. A lens unit having the imaging means;
A body unit that detachably holds the lens unit;
The lens unit transmits the image data to the main unit,
The main unit, the imaging apparatus according to claim 1 or 2, characterized in that it has and the display unit and the interpolated image data generating means.