JP2016131378A - Imaging apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an imaging apparatus that performs a brightness-comparison and composition process simultaneously with an image capture process and realizes functions convenient for a user.SOLUTION: The imaging apparatus includes: interval image capturing means 51 for performing an interval image capturing process; brightness-comparison and composition means 54 for performing a brightness- comparison and composition process using images sequentially obtained by the interval image capturing process; and image-under-composition display means 55 which, when a first operation has been performed, displays a composite image in a first memory area which is being used as a composition buffer of the brightness-comparison and composition process on an LCD monitor without stopping the interval image capturing process.SELECTED DRAWING: Figure 5

Description

  The present invention relates to an imaging apparatus that acquires an image by forming an optical image on an imaging sensor.

  In recent years, with the advancement and popularization of digital cameras, there are many new video expression methods that did not exist in the film camera era, using digital cameras for various shooting applications. One of them is a method of creating a new video using a large number of still images (generally exceeding several hundreds) obtained by fixing a digital camera to a tripod and performing interval shooting. is there. Specifically, in order to create a photo that increased the light trail of fireflies moving in the shooting screen and a photo that left the light trail of stars moving in the night sky due to the diurnal motion of the earth, There is a case where a synthesis process called bright synthesis is performed.

  The comparatively bright combination process is performed by the following procedure, for example. First, the first of a large number of still images to be processed is set as an initial value in the compositing memory area. Then, the brightness of the same pixel is compared between the second still image and the first still image set in the compositing memory area, and the pixel with the higher brightness is written back to the compositing memory area. This process is performed for all the pixels, and the composite image of the first still image and the second still image is held in the compositing memory area. After that, for the third and subsequent still images, the luminance of the same pixel in the synthesized image in the synthesis memory area and the still image to be processed is compared, and the process of writing back the higher luminance pixel to the synthesis memory area is performed. It is performed for all pixels and the above steps are repeated for all still images to be processed.

  By performing the above-described comparatively bright combination processing using a large number of still images obtained by interval shooting of the digital camera, a combined image as if it has been exposed for a long time is obtained. The comparatively bright combination process is generally executed by software installed in a personal computer (hereinafter referred to as a PC). In other words, the photographer generally performs interval shooting using a digital camera, captures a large number of obtained images into a PC, and performs comparatively bright combination processing using PC software.

  The following describes the advantages and disadvantages of conventional film camera long-time exposure, digital camera normal long-time exposure, digital camera addition processing long-time exposure, and comparatively bright combination processing using a PC. To do. The long exposure by the addition process of the digital camera is a long exposure using the technique described in Patent Document 1, for example.

(1) Long exposure of film camera <Advantages>
-For low-light subjects, if the exposure is performed for a long time, if the exposure time is doubled, the rule that the exposure can be brightened by one step does not hold and exposure becomes difficult (in general, “reciprocity law” It has a characteristic called "failure"). Using this property, it is possible to perform long exposures in the order of time in a dark environment (however, depending on the environment, the night sky is bright in Japan, so it can take up to 1 to 2 hours with ISO 100 film. Is the limit). In the night sky, it is possible to take a picture in which the light trail of the star remains without making the low-illuminance part that is the background of the star too bright.
<Disadvantages>
・ Experience values are required to determine exposure due to reciprocity failure.
-Color covering is likely to occur.
-In an environment where subjects with large brightness differences are mixed, the high brightness part will be overexposed (capturing of starlight trails for 1 hour with urban scenery is impossible).
・ The longer you leave the light trail, the larger the aperture value and the lower sensitivity film will be used, so there will be no dark star (light star) light trail (generally the limit grade, limit grade) And so on).
・ I don't know the progress.
・ I don't know the result right after shooting.

(2) Normal long exposure of digital cameras <Advantages>
・ Since there is no characteristic of reciprocity failure even for low-illuminance subjects, if the exposure time is doubled, it can be photographed one step brighter.
-With an exposure time of 20 seconds or less with a wide-angle lens, and setting the ISO sensitivity to the high sensitivity side, it is suitable for applications where shooting of stars is stopped.
・ Color correction is easy.
・ You can see the result immediately after shooting.
<Disadvantages>
・ Because there is no characteristic of reciprocity failure, it is unsuitable for time-order photography itself (it is impossible in practice because the whole image is blown out).
・ Depending on the capability of the image sensor and the shooting environment, if there is no cooling mechanism, spotted thermal noise is generated in the screen. Even if cooling is performed, it is necessary to have a mechanism for preventing condensation due to cooling, which tends to be expensive and large equipment.
-It is difficult to reduce random noise.
・ The progress during the exposure is unknown.

(3) Long exposure by digital camera addition processing <Advantages>
-Since the image sensor is read and digitized at regular intervals, it is possible to maintain gradation even if exposure is longer than the normal long exposure of a digital camera.
・ Color correction is easy.
・ You can know the progress of exposure.
・ You can see the result immediately after shooting.
<Disadvantages>
・ Because there is no characteristic of reciprocity failure, it is unsuitable for time-order photography itself (it is impossible in practice because the whole image is blown out).
-It is difficult to reduce random noise.
・ Although it takes a short time to read out data from the sensor in the middle of the entire exposure time, the time continuity is lost. Not as long as the focal length is longer.)

(4) Comparative bright combination processing using PC <Advantages>
-Since the composition method is such that the exposure determined by one image is almost maintained, the exposure determination is easy.
・ Color correction is easy.
・ Even if there is a mixture of subjects with large brightness differences, it will be difficult to skip over white areas (if you are shooting a photo that leaves a star trail along with a cityscape, the morning will occur unless there is an unexpected light at the start of shooting) The light trail can be extended for hours until
-Since exposure can be determined with a single shot, it is possible to perform high-sensitivity shooting, and it is possible to leave a light trail of a dark star (light star) that was impossible with film.
・ The thermal noise is negligible because exposure is not performed to such an extent that the thermal noise affects the image quality. It is not necessary to have a special cooling mechanism.
・ Random noise can be reduced as the number of composites increases, compared to other methods.
-By deliberately eliminating time continuity, it is possible to naturally express a composition with more fireflies. Even in the case of shooting light trails of stars, there are cases in which expressions that make use of discontinuities are used.
<Disadvantages>
・ Although it takes a short time to read out data from the sensor in the middle of the entire exposure time, the time continuity is lost. Not as long as the focal length is longer.)
-Since the comparatively bright combination processing is performed on the PC after shooting, the progress is not known.
-Since a comparatively bright combination process is performed on the PC after shooting, the result is not known immediately after shooting.

  As described above, the long-time exposure of the conventional digital camera (above (2) and (3)) is mainly due to the absence of the characteristic of reciprocity failure, and the long-time exposure of the film camera (above (1) ) In addition, there are many inconveniences in long-time exposure with a film camera.

  The present invention has been made in view of the above, and an object of the present invention is to provide an imaging apparatus capable of performing comparatively bright combination processing while performing shooting processing and realizing functions that are more user-friendly for the user. .

  In order to solve the above-described problems and achieve the object, the present invention repeats exposure and reading of the imaging sensor at a predetermined cycle in an imaging device including an imaging sensor, a storage unit, and a display unit. Interval photographing means for performing interval photographing processing, which is processing for sequentially obtaining a plurality of images, and a first image and a second image among the plurality of images sequentially obtained by the interval photographing processing A comparatively bright composite process is performed using and the processing result is stored in the storage unit as a composite image, and for the third and subsequent images, the image and the composite image stored in the storage unit are used. A comparatively bright combination means for repeatedly performing a comparatively bright combination process and repeatedly storing the processing result in the storage unit as a new combined image, and the interval photographing means includes automatic focusing Function or automatic exposure control function is set, automatic focusing or automatic exposure control is performed when the first image is acquired, and when the second and subsequent images are acquired, the first image is acquired. It is characterized by using the result of the automatic focusing or automatic exposure control performed.

  According to the present invention, it is possible to perform a comparatively bright combination process while performing a shooting process, thereby realizing an effect that a user-friendly function can be realized.

FIG. 1-1 is a top view of the digital camera according to the embodiment. FIG. 1B is a front view of the digital camera according to the embodiment. FIG. 1C is a back view of the digital camera according to the embodiment. FIG. 2 is a block diagram illustrating a configuration of a control system of the digital camera according to the embodiment. FIG. 3 is a diagram illustrating an example of a composite image obtained by the comparatively bright combination process. FIG. 4 is a diagram for explaining an initial setting screen for interval composite shooting and screen transition by button operation. FIG. 5 is a functional block diagram showing a functional configuration of a CPU block related to interval composite shooting. FIG. 6 is a flowchart illustrating a processing procedure of interval shooting processing. FIG. 7 is a flowchart showing a processing procedure of comparatively bright combination processing. FIG. 8 is a flowchart illustrating the processing procedure of the shooting setting determination process. FIG. 9 is a flowchart showing a processing procedure of interval image file output processing. FIG. 10 is a flowchart illustrating the processing procedure of the image synthesis display process. FIG. 11 is a flowchart showing the processing procedure of the synthesis buffer initialization process. FIG. 12A is a timing chart illustrating a processing state during the interval composite shooting. FIG. 12-2 is a timing chart illustrating a processing state during the interval composite shooting. FIG. 12C is a timing chart illustrating a processing state during the interval composite shooting. FIG. 12-4 is a timing chart illustrating a processing state during the interval composite shooting. FIG. 13A is a timing chart illustrating a processing state when the first operation is performed during the interval composite shooting. FIG. 13-2 is a timing chart illustrating a processing state when the second operation is performed during the interval composite shooting. FIG. 13C is a timing chart illustrating a processing state when the second operation is performed during the interval composite shooting.

  Embodiments of an imaging apparatus according to the present invention will be described below in detail with reference to the accompanying drawings. The embodiment described below is an example in which the present invention is applied to a digital camera.

  First, the configuration of the digital camera according to the present embodiment will be described. FIG. 1 is a diagram illustrating an appearance of a digital camera according to the present embodiment. FIG. 1-1 is a top view of the digital camera, FIG. 1-2 is a front view of the digital camera, and FIG. It is a rear view of a camera.

  As shown in FIG. 1A, the digital camera according to the present embodiment has a sub LCD 1, a release button 2, and a mode dial 3 on the upper surface thereof. The sub LCD 1 is a display unit for displaying, for example, the number of shootable images. The release button 2 is a button that can be pushed in two stages. When the first stage is pushed, an AF (autofocus) operation can be performed, and when the second stage is pushed, an operation such as photographing can be performed. The mode dial 3 is operated when switching between various modes such as a shooting mode for shooting (recording) an image, a playback mode for playing back a recorded image, and a SETUP mode for camera setting.

  In addition, as shown in FIG. 1-2, the digital camera according to the present embodiment includes a strobe light emitting unit 4, a remote control light receiving unit 6 that receives an infrared signal from a remote control terminal (not shown), and a lens barrel unit. 7 and an optical viewfinder (front surface) 8. Further, a side surface of the digital camera according to the present embodiment is provided with a memory card slot for inserting a memory card 80 to be described later and a battery accommodating portion for accommodating a battery. The memory card slot and the battery accommodating portion are covered with a lid. It is occluded by the body 9.

  In addition, as shown in FIG. 1C, the digital camera according to the present embodiment includes an autofocus LED (AFLED) 10, a strobe LED 11, an LCD monitor 12, and an optical viewfinder (back surface) 13 on the back surface. Have. The AFLED 10 is an LED that is turned on when the autofocus is activated. The strobe LED 11 is an LED that is turned on when strobe light is emitted. The LCD monitor 12 is a display unit used as an electronic viewfinder during display of various setting screens, display of reproduced images, and shooting.

  Further, on the back surface of the digital camera according to the present embodiment, a ZOOM (WIDE) switch 14 operated during wide-angle zoom, a ZOOM (TELE) switch 15 operated during telephoto zoom, a power switch 16, and a playback switch. 17, a self-timer / deletion switch 18 that is operated when the self-timer is activated and when an image is deleted, a MENU / OK switch 19 that is operated when a menu is selected or a selected item is confirmed, and an LCD monitor 12 Left / image confirmation switch 20 that is operated when the upper cursor is moved to the left or when a captured image is confirmed on the LCD monitor 12, and a right switch that is operated when the cursor on the LCD monitor 12 is moved to the right. 21 and the operation when moving the cursor on the LCD monitor 12 or when performing macro photography Down / macro switch 22, up / strobe switch 23 operated when the cursor on LCD monitor 12 is moved up or when switching the strobe mode, and DISPLAY switch operated when switching display on LCD monitor 12 24 is provided.

  FIG. 2 is a block diagram showing the configuration of the control system of the digital camera according to the present embodiment. The digital camera according to the present embodiment performs pre-processing on the CCD 101 that photoelectrically converts the light incident through the lens barrel unit 7 described above and outputs it as an electrical signal, and preprocesses the analog electrical signal that is output from the CCD 101 to generate a digital signal. F / E (front end) -IC 102 to be output as a digital camera processor (hereinafter simply referred to as “processor”) 104 that processes digital signals from the F / E-IC 102 and controls various operations of the digital camera. With.

  The lens barrel unit 7 includes a zoom optical system 71 including a zoom lens 71a and a zoom motor 71b for capturing an optical image of a subject, a focus optical system 72 including a focus lens 72a and a focus motor 72b, an aperture 73a and an aperture motor 73b. A diaphragm unit 73, a mechanical shutter unit 74 including a mechanical shutter 74a and a mechanical shutter motor 74b, and a motor driver 75 for driving each motor are provided. The motor driver 75 is driven and controlled by a drive command from a CPU block 1043 described later in the processor 104.

  The CCD 101 is an imaging sensor that receives light incident through the lens barrel unit 7 and photoelectrically converts the optical image to output image data corresponding to the optical image. In the digital camera according to this embodiment, the CCD 101 is used as the image sensor, but another image sensor such as a CMOS image sensor may be used instead of the CCD 101. When a CMOS image sensor is used as the imaging sensor, the configuration of the control system is slightly changed, but the description thereof is omitted here.

  The F / E-IC 102 includes a CDS 1021 that performs correlated double sampling for image noise removal, an AGC 1022 that performs gain adjustment, an A / D 1023 that converts an analog signal into a digital signal, and a first CCD signal processing block (described later) in the processor 104. A TG (Timing Generator) 1024 that generates drive timing signals for the CCD 101, the CDS 1021, the AGC 1022, and the A / D 1023 based on a vertical synchronization signal (VD signal) and a horizontal synchronization signal (HD signal) supplied from the H.1041. The operation of each unit in the F / E-IC 102 is controlled by a CPU block 1043 described later in the processor 104.

  The processor 104 includes a first CCD signal processing block 1041, a second CCD signal processing block 1042, a CPU block 1043, a local SRAM 1044, a USB block 1045, a serial block 1046, a JPEG / CODEC block 1047, a RESIZE block 1048, and a TV signal display. A block 1049 and a memory card controller block 10410 are included. The above-described units in the processor 104 are connected to each other via a bus line.

  The first CCD signal processing block 1041 performs white balance correction and gamma correction on the image data input from the CCD 101 via the F / E-IC 102, and controls the timing of the image data. The HD signal is supplied to the TG 1024. The second CCD signal processing block 1042 converts the input image data into luminance data / color difference data by filtering processing.

  The CPU block 1043 controls operation of each part of the digital camera according to the present embodiment. Specifically, the CPU block 1043 controls the sound recording operation by the sound recording circuit 1151. The voice recording circuit 1151 records the voice signal converted by the microphone 1153 and amplified by the microphone amplifier 1152 in accordance with a command from the CPU block 1043. The CPU block 1043 also controls the sound reproduction operation by the sound reproduction circuit 1161. In response to a command from the CPU block 1043, the audio reproduction circuit 1161 reproduces an audio signal recorded in an appropriate memory, inputs the audio signal to the audio amplifier 1162, and outputs audio from the speaker 1163. Further, the CPU block 1043 controls the operation of the strobe circuit 114 to emit illumination light from the strobe light emitting unit 4. In addition, the CPU block 1043 executes various processes for realizing a function of performing comparatively bright combination processing while performing interval shooting processing (hereinafter referred to as interval combined shooting) as a characteristic function in the present embodiment. This will be described in detail later.

  The CPU block 1043 is connected to the sub CPU 109 arranged outside the processor 104. The sub CPU 109 controls display on the sub LCD 1 via the LCD driver 111. The sub CPU 109 is connected to the AF LED 10, the strobe LED 11, the remote control light receiving unit 6, the buzzer 113, and the operation key unit 90. The operation key unit 90 includes the release button 2, the mode dial 3, the ZOOM (WIDE) switch 14, the ZOOM (TELE) switch 15, the power switch 16, the playback switch 17, the self-timer / delete switch 18, and the MENU / OK switch 19. , Left / image confirmation switch 20, right switch 21, down / macro switch 22, up / strobe switch 23, and display switch 24. The sub CPU 109 uses the output signals from the operation key unit 90 and the remote control light receiving unit 6 as user operation information, controls the operation of the AFLED 10, the strobe LED 11, and the buzzer 113 according to the user operation information, and also displays the user operation information. This is transmitted to the CPU block 1043 in the processor 104.

  The local SRAM 1044 is a memory that temporarily stores data necessary for control. The USB block 1045 performs USB communication with an external device such as a computer terminal connected to the USB connector 122. The serial block 1046 performs serial communication with an external device such as a computer terminal connected to the RS-232C connector 1232 via the serial driver circuit 1231.

  The JPEG / CODEC block 1047 performs processing for compressing the captured image data in the JPEG format and for expanding the recorded image data compressed in the JPEG format. The RESIZE block 1048 performs processing for enlarging / reducing the size of image data by interpolation processing.

  The TV signal display block 1049 converts the image data into a video signal for display on an external display device such as the LCD monitor 12 or TV. An LCD driver 117 is connected to the TV signal display block 1049, and an image is displayed on the LCD monitor 12 driven by the LCD driver 117. In addition, when the video signal AMP 118 is connected to the TV signal display block 1049 and the video jack 119 is connected to an external display device such as a TV, an image is displayed on the external display device.

  The memory card controller block 10410 is connected to the memory card throttle 121 and controls the memory card 80 inserted into the memory card throttle 121 and a general-purpose PCMCIA.

  Further, an SDRAM 103, a RAM 107, a ROM 108, and a built-in memory 120 are disposed outside the processor 104, and these are connected to the processor 104 by a bus line.

  The SDRAM 103 is a memory that temporarily stores image data when the processor 104 performs image processing. For example, the stored image data is input to the processor 104 from the CCD 101 via the F / E-IC 102, and “RAW-RGB” in a state where white balance correction and gamma correction are performed in the first CCD signal processing block 1041. "Image data", "YUV image data" in which luminance data / color difference data conversion has been performed in the second CCD signal processing block 1042, "JPEG image data" compressed in JPEG format in the JPEG / CODEC block 1047, etc. It is. The SDRAM 103 also includes a first memory area and a second memory area that are used in interval composite photography described later.

  The ROM 108 stores a control program written in a code readable by the CPU block 1043 and parameters for control. Note that these parameters may be stored in the built-in memory 120. When the power of the digital camera is turned on, the program is loaded into a main memory (not shown), and the CPU block 1043 controls the operation of each unit in accordance with the program and temporarily stores data necessary for control in the RAM 107 and the processor 104. And stored in the local SRAM 1044. In the present embodiment, a program for performing interval composite shooting described later is also stored in the ROM 108. In the present embodiment, the interval composite shooting is described as being realized by a program. However, in order to speed up the processing, for example, a part of processing such as comparatively bright combining processing is performed by ASIC (Application Specific Integrated Circuit). Alternatively, it may be implemented using dedicated hardware such as FPGA (Field-Programmable Gate Array).

  The built-in memory 120 is a memory for recording captured image data when the memory card 80 is not inserted into the memory card throttle 121. The RAM 107 is a memory used as a work area when the CPU block 1043 executes various programs.

  Next, characteristic interval composite shooting in the digital camera according to the present embodiment will be described. As described above, the interval composite shooting is a function of performing comparatively bright combining processing while performing interval shooting processing.

  The interval shooting process is a process of sequentially acquiring a plurality of images by repeatedly performing exposure and reading (reading of pixel data) of the CCD 101 that is an image sensor at a predetermined cycle.

  The comparatively bright combination process is a process that uses a plurality of images to compare the luminance for each pixel at the same position, and selects a higher luminance to generate a combined image. As described above, the comparatively bright combination process is first performed using the first image and the second image, and the processing result is stored as a combined image. Thereafter, the third and subsequent images are processed using the image and the composite image that is the previous processing result, and the processing result is stored as new composite image data. The above process is repeated for all the images to be processed, and a final composite image is obtained.

  In the digital camera according to the present embodiment, two memory areas in the SDRAM 103 are used to perform comparatively bright combination processing. Each of the two memory areas is a frame memory that holds data for one image. Hereinafter, one of the two memory areas is referred to as a first memory area, and the other is referred to as a second memory area. The first memory area is a memory used as a synthesis buffer for the comparatively bright combination process, and stores a composite image that is a result of the comparatively bright combination process. The second memory area is a memory used as a still image buffer before composition, and sequentially stores images acquired by interval shooting processing.

  FIG. 3 is a diagram illustrating an example of a composite image obtained by the comparatively bright combination process. The left side of the figure shows an image group to be processed, and the right side of the figure shows a synthesized image obtained by performing comparatively bright synthesis processing on these image groups. The composite image obtained by the comparative bright combination processing is a pixel having the maximum luminance of the image group. As shown in the example of FIG. 3, even if the image contains a landscape and a starry sky, the light trails of the stars due to the diurnal motion of the earth extend, and the part of the night sky without stars or the bright landscape It is possible to obtain a composite image that coexists without being white and is exposed for a long time. In the image group shown on the left side of FIG. 3, the number of images is limited in order to simplify the illustration, but in reality, a composite image shown on the right side of the figure is generated using over 300 images. The

  In the interval composite shooting, the image group that is the target of the comparative bright combination processing is an image that is sequentially acquired by the interval shooting processing, and each time an image is obtained by the interval shooting processing, the comparative bright combination processing using the image is performed. That is, the interval shooting process and the comparatively bright combination process are performed simultaneously. Thereby, various functions that are easy to use for the user as described later can be realized.

  The digital camera according to the present embodiment includes an operation mode for performing interval composite shooting (hereinafter referred to as interval composite shooting mode) as one of shooting modes. The interval composite shooting mode can be selected by operating the mode dial 3, for example. First, the initial setting of interval composite shooting will be described with reference to FIG. FIG. 4 is a diagram for explaining an initial setting screen for interval composite shooting and screen transition by button operation.

  After the user turns on the power of the digital camera by operating the power switch 16, selects the interval composite shooting mode by operating the mode dial 3, etc., and sets various shooting-related settings as desired, the MENU / OK switch 19 When is pressed, an initial setting screen for interval composite shooting shown in FIG. 4 is displayed on the LCD monitor 12. On the initial setting screen, the user operates the left / image confirmation switch 20 and the right switch 21 to select an item, and operates the down / macro switch 22 and the up / strobe switch 23 to set the setting contents of each item. By selecting, various settings related to interval composite shooting can be performed. Hereinafter, for convenience, the left / image confirmation switch 20, the right switch 21, the down / macro switch 22, and the up / strobe switch 23 are referred to as a left button, a right button, a down button, and an up button, respectively.

  FIG. 4A shows a time interval of an individual image shooting interval (that is, a time for instructing the digital camera to start the exposure of the next shooting from the start of exposure. This time is hereinafter referred to as an interval time). An example of a screen in a state where “digit” can be set is shown. The numerical value can be changed by operating the up button or the down button in the state of FIG. When the right button is operated, the screen of FIG. 4A transitions to the screen of FIG. 4B, and when the left button is operated, the screen of FIG. 4A transitions to the screen of FIG. To do.

  FIG. 4B shows an example of a screen in which the “minute digits” of the interval time can be set. The numerical value can be changed by operating the upper button or the lower button in the state of FIG. When the right button is operated, the screen of FIG. 4B transitions to the screen of FIG. 4C, and when the left button is operated, the screen of FIG. 4B transitions to the screen of FIG. To do.

  FIG. 4C shows an example of a screen in a state where the “second digit” of the interval time can be set. The numerical value can be changed by operating the up button or the down button in the state of FIG. Further, when the right button is operated, the screen of FIG. 4C transitions to the screen of FIG. 4D, and when the left button is operated, the screen of FIG. 4C transitions to the screen of FIG. 4B. To do.

  FIG. 4D is a diagram that is stored in the first memory area when the first memory area used as a synthesis buffer for the comparative bright combination process is reset by resetting the comparative bright combination process during interval composite shooting. The screen example of the state which can set whether the data which are stored, ie, the synthesized image produced | generated by the process so far, is preserve | saved is shown. By operating the up button and the down button in the state of FIG. 4D, the item “file output setting at the time of composite reset” is set to “leave the composite image before reset” or “leave nothing”. You can choose. Further, when the right button is operated, the screen of FIG. 4 (d) transitions to the screen of FIG. 4 (e), and when the left button is operated, the screen of FIG. 4 (d) transitions to the screen of FIG. 4 (c). To do. “Leave composite image before reset” is a setting for outputting a composite image up to immediately before resetting comparatively bright composite processing as an image file and storing it in the memory card 80 or the like. This is a setting that does not save the composite image until immediately before the composite processing is reset.

  FIG. 4E shows an example of a screen in a state where it can be set whether to save each image used for interval composite shooting. By operating the up button or the down button in the state of FIG. 4E, the items of “interval image file output setting” are set to “leave normal still image”, “leave composite still image”, “normal moving image”. “Leave”, “Leave synthetic video”, and “Leave nothing” can be selected. When the right button is operated, the screen of FIG. 4E transitions to the screen of FIG. 4A, and when the left button is operated, the screen of FIG. 4E transitions to the screen of FIG. 4D. To do. “Leave a normal still image” is a setting for outputting an image (still image) before composition as an image file and storing it in the memory card 80 or the like each time an image is acquired by the interval shooting process. “Leave a composite still image” is a setting for outputting a composite image (still image) up to that point as an image file and storing it in the memory card 80 or the like each time an image is acquired by interval shooting processing. “Leave normal moving image” is a setting for generating a moving image file with the pre-combine image (still image) as one frame of the moving image and storing it in the memory card 80 or the like every time an image is acquired by the interval shooting process. . “Leave composite video” is a setting that generates a video file with a composite image (still image) up to that point as one frame of the video every time an image is acquired by interval shooting processing and saves it in the memory card 80 or the like It is. “Nothing” means that images used for interval composite shooting will not be saved (however, if “File output setting at composite reset” is set to “Leave composite image before reset”) The composite image is saved.)

  Regardless of the initial setting screen displayed on the LCD monitor 12 in any one of FIGS. 4A to 4E, the setting contents of each item can be determined by pressing the MENU / OK switch 19. . Thereafter, when the release button 2 is pushed down to the second stage (full pressing operation), interval composite shooting is started.

  FIG. 5 is a functional block diagram showing a functional configuration of the CPU block 1043 related to interval composite shooting. As described above, each process in the interval composite shooting is realized by a program as an example. The CPU block 1043 has an interval photographing means 51, a photographing setting confirmation means 52, an interval image file output means 53, a comparatively bright composition means 54, and an intermediate composition image as functional configurations for executing each process in the interval composite photography. Display means 55 and synthesis buffer initialization means 56 are provided.

  The interval photographing means 51 executes “interval photographing processing”. A specific processing procedure of the “interval shooting process” executed by the interval shooting means 51 will be described later with reference to FIG.

  The shooting setting determination unit 52 executes “shooting setting determination processing”. A specific processing procedure of the “shooting setting determination process” executed by the shooting setting determination unit 52 will be described later with reference to FIG.

  The interval image file output means 53 executes “interval image file output processing”. A specific processing procedure of the “interval image file output process” executed by the interval image file output means 53 will be described later with reference to FIG.

  The comparatively bright combining means 54 executes “comparatively bright combining process”. A specific processing procedure of the “comparative bright combination processing” executed by the comparative bright combination means 54 will be described later with reference to FIG.

  The in-combination image display means 55 executes “in-combination image display process”. A specific processing procedure of the “synthesizing image display process” executed by the synthesizing image display means 55 will be described later with reference to FIG.

  The synthesis buffer initialization unit 56 executes “synthesis buffer initialization processing”. A specific processing procedure of the “synthesis buffer initialization process” executed by the synthesis buffer initialization unit 56 will be described later with reference to FIG.

  In the digital camera according to the present embodiment, among the above-described processes executed by the CPU block 1043 in the interval composite shooting mode, the “shooting setting confirmation process” and the “interval image file output process” are referred to as “interval shooting process”. It is executed sequentially in a form like a function call. The other “comparative bright combination processing”, “combination image display processing”, and “combination buffer initialization processing” are executed in parallel by multitasking.

  Hereinafter, the operation of interval composite shooting will be described with reference to the flowcharts of FIGS.

  FIG. 6 is a flowchart showing a processing procedure of “interval shooting process” executed by the interval shooting means 51 of the CPU block 1043. The flow of FIG. 6 is a main routine of interval composite shooting, and controls the timing of starting the “comparative bright combination processing” while performing the “interval shooting processing”.

  First, in step S101, processing for clearing the compositing process flag is performed, and in step S102, processing for initializing the composite number counter to 0 is performed. The in-combination processing flag is a flag indicating whether or not “comparative bright combination processing” is being executed. The composite number counter is a counter that indicates how many images are being combined in the “comparative bright combination processing”. The processes in steps S101 and S102 are processes for initializing variables in the program.

  Next, in step S103, “shooting setting confirmation processing” is performed. The “shooting setting determination process” is a process for determining a focus position and exposure by performing AF (automatic focusing) processing and AE (automatic exposure control) processing before performing a series of interval shooting. As described above, the “shooting setting confirmation process” is called from the “interval shooting process” in the form of a function call and is executed as a subroutine. The processing procedure of “shooting setting confirmation processing” will be described later.

  Next, in step S104, processing for starting measurement of the interval time is performed. This process is a process for operating an internal timer to measure the interval time.

  Next, in step S105, an exposure process is performed. The exposure process is a process for performing exposure of the CCD 101 which is an image sensor. In this process, data reading from the CCD 101 is not performed even after exposure is completed.

  Next, in step S106, it is determined whether or not a compositing process flag is set. This process is a process for determining whether or not the composition process of the previously captured image in the series of interval shooting processes has been completed with reference to a variable in the program. If the process of combining the previously captured image has not ended and the combining process flag is set (step S106: Yes), the process waits until the combining process ends. Then, when the composition processing of the previously captured image is completed and the composition processing flag is cleared (step S106: No), the processing proceeds to the next processing.

  Next, in step S107, a process of reading data from the CCD 101 which is an image sensor is performed. In this process, an image obtained by exposure of the CCD 101 is read from the CCD 101 and stored in the second memory area.

  Next, in step S108, it is determined whether or not saving of an image used for interval composite shooting is set according to the initial setting described above. If saving of an image used for interval composite shooting is set (step S108: Yes), "interval image file output processing" is performed, and if saving of an image used for interval composite shooting is not set (step S108: No), “interval image file output processing” is skipped.

  Next, in step S109, “interval image file output processing” is performed. The “interval image file output process” is a process for storing an image used for interval composite shooting based on an initial setting by the user. As described above, the “interval image file output process” is called in the form of a function call from the “interval shooting process” and is executed as a subroutine. The processing procedure of “interval image file output processing” will be described later.

  Next, in step S110, processing for setting a compositing processing flag is performed. This process is a process for setting a variable in the program.

  Next, in step S111, a process for instructing the start of the “comparative bright combination process” is performed. This process is a process for starting a “comparative bright combination process” executed in parallel with the “interval shooting process” by multitasking. The processing procedure of “comparatively bright combination processing” will be described later.

  Next, in step S112, it is determined whether or not an operation for ending the interval shooting process has been performed. The operation for ending the interval shooting process is, for example, an operation of pushing the release button 2 to the second stage (full pressing operation). If the operation for ending the interval shooting process has been performed (step S112: Yes), the interval shooting process is ended. If the operation for ending the interval shooting process has not been performed (step S112: No), the process proceeds to the next process.

  Next, in step S113, it is determined whether or not the interval time has elapsed. This process is a process of determining whether or not the next image capturing timing has arrived based on the interval time specified by the user through the initial setting described above. If the interval time has not elapsed and the next shooting timing has not arrived (step S113: No), the process waits until the interval time elapses. When the next shooting timing comes after the interval time has elapsed (step S113: Yes), the process returns to step S104 to start measuring the interval time, and the next image is shot.

  FIG. 7 is a flowchart showing the processing procedure of “comparative bright combination processing” executed by the comparative bright combination means 54 of the CPU block 1043. The flow of FIG. 7 operates in parallel with the flow of FIG. 6 by multitasking. Since the details of the comparatively bright combination process have already been described, the description thereof is omitted here.

  First, in step S201, it is determined whether or not the composite number counter is zero. This process is a process for determining whether or not to initialize the first memory area used as the synthesis buffer. The composite number counter becomes 0 at the time of the first shooting after the start of the “interval shooting process” or the first shooting after the “composite buffer initialization process” described later. If the composite number counter is 0, that is, the first photographing after starting the “interval photographing process” or the first photographing after the “composite buffer initialization process” (step S201: Yes), the process proceeds to step S202. . On the other hand, when the composite number counter is not 0, that is, when it is not the first shooting after starting the “interval shooting process” or the first shooting after the “composite buffer initialization process” (step S201: No). Proceed to step S203.

  In step S202, an image stored in the second memory area, that is, an image acquired by the “interval shooting process” is copied to the first memory area.

  In step S203, the image stored in the second memory area, that is, the image acquired by the “interval shooting process”, and the composite image stored in the first memory area, that is, generated by the previous comparatively bright combination process. Using the synthesized image, a comparatively bright synthesis process is performed, and a new synthesized image as a processing result is stored in the second memory area.

  Next, in step S204, a process of adding 1 to the composite number counter is performed.

  Next, in step S205, a process for clearing the compositing process flag is performed.

  FIG. 8 is a flowchart showing the processing procedure of the “shooting setting determination process” executed by the shooting setting determination unit 52 of the CPU block 1043. The flow of FIG. 8 is a subroutine called from the flow of FIG.

  First, in step S301, it is determined whether or not the AF mode is on. The AF mode is a mode for designating whether or not AF (automatic focusing) processing is performed at the time of shooting, and indicates that AF processing is performed when the AF mode is on, and manual (manual) when the AF mode is off. ) Indicates focusing. If the AF mode is on (step S301: Yes), the process proceeds to step S302, and AF processing is performed in step S302. On the other hand, if the AF mode is off (step S301: No), the AF process of step S302 is skipped and the process proceeds to step S303.

  Next, in step S303, it is determined whether or not the AE mode is on. The AE mode is a mode for designating whether or not to perform AE (automatic exposure control) processing at the time of shooting, and indicates that AE processing is performed when the AE mode is on, and manual (manual) when the AE mode is off. ) Indicates that exposure control is performed. If the AE mode is on (step S303: Yes), the process proceeds to step S304, and the AE process is performed in step S304. On the other hand, if the AE mode is off (step S303: No), the process is terminated as it is.

  The “shooting setting confirmation process” shown in the flow of FIG. 8 is performed when the first image is acquired by the “interval shooting process”. When the AF mode is on, AF processing is performed when the first image is acquired, and the processing result is held. Then, when acquiring the second and subsequent images, the result of AF processing at the time of acquiring the first image is used as it is. When the AE mode is on, AE processing is performed when the first image is acquired, and the processing result is held. When acquiring the second and subsequent images, the result of the AE process at the time of acquiring the first image is used as it is.

  FIG. 9 is a flowchart showing the processing procedure of “interval image file output processing” executed by the interval image file output means 53 of the CPU block 1043. The flow of FIG. 9 is a subroutine called from the flow of FIG.

  First, in step S401, processing for confirming the setting content of the item “interval image file output setting” (see FIG. 4) set in the initial setting described above is performed. When the setting content of the “interval image file output setting” item is “leaves a normal still image”, the process proceeds to step S402, and when it is “leaves a composite still image”, the process proceeds to step S403. "", The process proceeds to step S404. If "leave the composite video", the process proceeds to step S405. If "nothing is left", the process ends.

  In step S402, the data stored in the second memory area, that is, the pre-combination image acquired by the “interval shooting process” is output as a still image file and stored in the memory card 80 or the like.

  In step S403, the data stored in the first memory area, that is, the composite image generated up to that point by the “comparative bright combination processing” is output as a still image file and stored in the memory card 80 or the like. Done.

  In step S404, data stored in the second memory area, that is, a moving image file in which the pre-combination image acquired by the “interval shooting process” is a frame of the moving image is generated and stored in the memory card 80 or the like. Is done. Each time a new image is acquired by the “interval shooting process”, this moving image file is added as one frame of the moving image.

  In step S405, a moving image file is generated in which the data stored in the first memory area, that is, the combined image generated up to that point by the “comparative bright combining process” is one frame of the moving image, and is stored in the memory card 80 or the like. Processing to save is performed. Each time a new image is acquired by the “interval shooting process”, a composite image up to that point is added as one frame of the moving image file.

  FIG. 10 is a flowchart showing a processing procedure of “combination image display process” executed by the compositing image display means 55 of the CPU block 1043. The flow of FIG. 10 is started by performing a predetermined first operation, for example, an operation of pressing the release button 2 to the first stage (half-pressing operation) during the interval composite shooting operation. It operates in parallel with the flow of FIG. 6 and the flow of FIG.

  First, in step S501, it is determined whether or not the compositing process flag is being set. This process is a process for waiting for the next process until the compositing process flag is cleared. A polling process is performed during the period when the compositing process flag is set (step S501: Yes). When the in-combination flag is cleared (step S501: No), the process proceeds to step S502.

  Next, in step S502, it is determined whether or not the composite number counter is zero. This process is a process for waiting for the next process until the composite number counter reaches a value other than 0 (until an image to be displayed is generated). During the period when the composite number counter is 0 (step S502: Yes), polling processing is performed. When the composite number counter becomes a value other than 0 (step S502: No), the process proceeds to step S503.

  Next, in step S503, the data stored in the first memory area, that is, the composite image generated up to that point by the “comparative bright combination processing” is generated, and the value of the composite number counter, that is, the composite image is generated. A process of displaying on the LCD monitor 12 is performed together with the number of still images used for the above.

  Next, in step S504, it is determined whether the display time has elapsed. The display time may be a predetermined fixed value, or may be set by the user. The elapsed display time may be determined by, for example, operating the internal timer at the start of display in step S503 and checking the value of the internal timer. During the period when the display time has not elapsed (step S504: No), the display on the LCD monitor 12 is maintained (no processing). When the display time has elapsed (step S504: Yes), the process proceeds to step S505.

  In step S505, processing for terminating the display on the LCD monitor 12 is performed.

  FIG. 11 is a flowchart showing the processing procedure of “synthesis buffer initialization processing” executed by the synthesis buffer initialization means 56 of the CPU block 1043. The flow of FIG. 11 is started by performing a predetermined second operation, for example, an operation of pressing the self-timer / deletion switch 18 during the interval composite shooting operation, and the flow of FIG. It operates in parallel with the flow 7.

  First, in step S601, it is determined whether or not the composition processing flag is being set. This process is a process for waiting for the next process until the compositing process flag is cleared. A polling process is performed during the period when the compositing process flag is set (step S601: Yes). When the compositing process flag is cleared (step S601: NO), the process proceeds to step S602.

  In step S602, a process of initializing the composite number counter to 0 is performed. By this process, the branch of step S201 in the flow shown in FIG. 7 becomes Yes, and the “comparative bright combination process” is reset.

  Next, in step S603, processing for confirming the setting content of the item “file output setting at composition reset” (see FIG. 4) set in the initial setting described above is performed. If the setting content of the “composition reset file output setting” item is “leave the composite image before reset”, the process proceeds to step S604, and if it is “leave nothing”, the process ends.

  In step S604, data stored in the first memory area, that is, a composite image up to immediately before resetting the “comparatively bright composite process” is output as an image file and stored in the memory card 80 or the like.

  12A to 12D are timing charts showing processing states during the interval composite shooting. In the present embodiment, since “comparative light combination processing” is performed by software (program), it takes about 1 second. However, “comparative light combination processing” is performed using dedicated hardware. In this case, the processing time can be shortened. In the timing charts of FIGS. 12-1 to 12-4, it is assumed that the processing time of the above-mentioned “comparative bright combination processing” is almost stable, and the interval composite shooting is performed by setting the interval time and the exposure time. It shows how the processing state will be during execution.

  As described above, the second memory area is a memory area in which images acquired by the interval shooting process are sequentially stored. During the period indicated as “write” in the figure, writing from the CCD 101 as the image sensor to the second memory area is performed. In addition, the period indicated as “available for output” in the figure is a period during which memory read or file output is possible because the value does not change during memory read.

  As described above, the first memory area is a memory area for storing a composite image that is a result of the “comparatively bright composite process”. The period indicated as “copying process” or “combining process” in the figure is a period in which the contents of the memory may be changed by the “comparative bright combination process”. In addition, the period indicated as “available for output” in the figure is a period during which memory read or file output is possible because the value does not change during memory read.

  FIG. 12A is a timing chart in the case where the exposure time is relatively long and the interval time is set longer than that. It is a timing chart in a setting that is suitable for an expression that overlaps the light of fireflies at night and may be free between shootings.

  FIG. 12-2 shows a timing chart when the exposure time is relatively long and the setting of the interval time is shorter than the shortest possible cycle. It is a timing chart in a setting suitable for an expression that leaves a light trail of stars, which is taken at night and is taken as short as possible between shooting.

  FIG. 12-3 shows a timing chart in the case where the exposure time is relatively short, and the setting of the interval time is long as in the example of FIG. 12-1. Suitable for expressions that are daytime and do not require time connections.

  FIG. 12-4 shows a timing chart in the case where the exposure time is relatively short and the setting of the interval time is shorter than the shortest possible cycle. Although it is an expression that is daytime and does not require temporal connection, it is suitable for recording an event that changes faster than the example of FIG. 12-3 as one image.

  13-1 to 13-3 illustrate the first operation (for example, half-press operation of the release button 2) and the second operation (for example, the self-timer / deletion switch 18) during the interval composite shooting. It is a timing chart which shows a processing state at the time of (pressing operation) of being performed.

  In FIG. 13A, the first operation (for example, half-press operation of the release button 2) is performed during the interval composite shooting, and the “interval shooting process” is stopped without stopping the “interval shooting process”. 10 is a timing chart in the case of performing “combination image display processing”. When the state of the first memory area is “output enabled”, if the first operation is performed, the data stored in the first memory area immediately, that is, the “comparative bright combination process” is generated up to that point It is shown that the synthesized image displayed is displayed on the LCD monitor 12. When the first operation is performed when the state of the first memory area is “combining process”, the display is waited until the combining process is completed.

  In FIG. 13B, when the state of the first memory area is “output enabled”, the second operation (for example, the pressing operation of the self-timer / deletion switch 18) is performed, and the “interval shooting process” is stopped. 12 is a timing chart when the “synthesis buffer initialization process” shown in FIG. In this case, when the second operation is performed, the composite number counter is immediately initialized. However, even if the first operation is performed between the initialization of the composite number counter and the completion of the first copy process, the display operation is kept waiting.

  In FIG. 13C, when the state of the first memory area is “compositing process”, a second operation (for example, pressing operation of the self-timer / delete switch 18) is performed, and “interval shooting process” is performed. 12 is a timing chart in the case of performing “synthesis buffer initialization processing” shown in FIG. 11 without stopping. In this case, when the second operation is performed, the composite number counter initialization process is awaited until the “comparative bright combination process” is completed. Furthermore, even if the first operation is performed after the composite number counter is initialized and before the first copy process is completed, the display operation is kept waiting.

  As described above in detail with specific examples, according to the digital camera according to the present embodiment, by providing an interval composite shooting function for performing comparatively bright combination processing while performing interval shooting processing, You can do things like this.

  First, since the intermediate composite image can be displayed on the LCD monitor 12 while the interval photographing process is continued, the photographer can have a finished image during photographing.

  In addition, it is possible to reset the comparatively bright composite process while continuing the interval shooting process, and to save each image obtained by the comparative bright composite process so far. Even if light or airplane light trails enter, data that creates moving images later uses such light to maintain temporal connections and re-composes the compositing process as a still image that leaves light trails. This can be done while shooting on site.

  Further, it is possible to create a plurality of still images having a desired length of light trace visually confirmed by the user from the same shooting data while making data for creating a moving image as long as possible.

  In addition, when the free space of the recording medium such as the built-in memory 120 or the memory card 80 of the digital camera is small, only the combination result is recorded, and when there is a free space, all interval shooting data is left. it can.

  Further, in the case of shooting that leaves a star light trail, original data for easily creating a moving image in which the star light trail gradually extends can be obtained. In the case of a heavy user, there is a strong tendency to fine-tune a still image before creating moving image data, but it can withstand such a request.

  In addition, even a user who is not good at post-processing on a PC can shoot a moving image (so-called slow-speed moving image) obtained by thinning out a video over a long period of time with only a digital camera.

  Also, even for users who are not good at post-processing on a PC, in the case of shooting that leaves star light trails, a moving image in which the star light trails gradually extend can be shot only with a digital camera. can do.

  In addition, the photographer can easily grasp not only the composite image held in the first memory area but also how many images the composite image is composed while photographing.

  In addition, while performing a series of interval composite shooting, the AF function and AE function react to a subject that has temporarily entered the field of view temporarily, changing the control value for only a part of the series of shot images. Thus, it is possible to avoid the problem that the still image or the moving image obtained by the comparatively bright combination process is uncomfortable.

  Note that the interval composite shooting function that is characteristic of the digital camera according to the present embodiment is realized by a program executed by the CPU block 1043 as an example, as described above. A program for realizing the function of interval composite shooting is provided by being incorporated in advance in the ROM 108 of the digital camera, for example. In addition, a program such as a CD-ROM, a flexible disk (FD), a CD-R, a DVD (Digital Versatile Disc) or the like is installed in a file that can be installed or executed in a program that realizes the interval composite shooting function. The information may be provided by being recorded on a recording medium that can be read by the user. Furthermore, a program for realizing the function of interval composite shooting may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. Further, a program for realizing the interval composite shooting function may be provided or distributed via a network such as the Internet.

  The program for realizing the interval composite shooting function in the digital camera according to the present embodiment includes the interval shooting unit 51, the shooting setting determination unit 52, the interval image file output unit 53, the comparatively bright combining unit 54, and the image that is being combined. The module configuration includes the processing functions of the display means 55 and the composite buffer initialization means 56. As actual hardware, the CPU block 1043 reads out and executes the program from the ROM 108, thereby executing the processing functions. Are loaded onto a main memory (for example, SDRAM 103), and the above-described processing functions are generated on the main memory.

  Although specific embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments as they are, and various modifications are made without departing from the scope of the invention in the implementation stage. Can be embodied. In other words, the configuration and operation of the digital camera described above are merely specific examples, and various modifications can be made according to the application and purpose.

DESCRIPTION OF SYMBOLS 12 LCD monitor 51 Interval imaging | photography means 52 Shooting setting confirmation means 53 Interval image file output means 54 Comparative bright composition means 55 Composite image display means 56 Synthesis buffer initialization means 101 CCD
103 SDRAM
1043 CPU block

JP 2009-239600 A

Claims (6)

In an imaging device including an imaging sensor, a storage unit, and a display unit,
Interval imaging means for performing interval imaging processing, which is processing for sequentially acquiring a plurality of images by repeatedly performing exposure and reading of the imaging sensor at a predetermined period;
Of the plurality of images sequentially acquired by the interval shooting process, the first image and the second image are used to perform comparatively bright combination processing, and the processing result is stored in the storage unit as a combined image. For the third and subsequent images, a process of performing the comparatively bright combining process using the image and the combined image stored in the storage unit and storing the processing result as a new combined image in the storage unit. A comparatively bright and bright synthetic means,
When the automatic focusing function or the automatic exposure control function is set, the interval photographing unit performs automatic focusing or automatic exposure control when acquiring the first image, and when acquiring the second and subsequent images. An image pickup apparatus using the result of automatic focusing or automatic exposure control performed at the time of acquiring the first image.   The imaging apparatus according to claim 1, further comprising a first image file output unit that outputs the acquired image as an image file each time an image is acquired by the interval shooting process.   2. The image processing apparatus according to claim 1, further comprising a second image file output unit that outputs a composite image stored in the storage unit as an image file each time an image is acquired by the interval photographing process. Or the imaging device of 2.   4. The apparatus according to claim 1, further comprising a first moving image file generating unit that generates a moving image file by using the acquired image as one frame of a moving image every time an image is acquired by the interval shooting process. The imaging device according to claim 1.   Each time an image is acquired by the interval shooting process, the image processing apparatus further includes a second moving image file generating unit that generates a moving image file by using the composite image stored in the storage unit at that time as one frame of the moving image. The imaging device according to any one of claims 1 to 4. A composite image display means for displaying the composite image stored in the storage unit on the display unit without stopping the interval photographing process when the first operation is performed;
And a release button that can be pushed in two stages,
The imaging apparatus according to claim 1, wherein the first operation is an operation of pushing down to a first stage of the release button.