JP2006287375A - Photographic apparatus, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photographic apparatus, capable of generating images that can be obtained by carrying-out photographing under a long time exposure, in a state with mobile objects, such as celestial bodies, stopped. <P>SOLUTION: When a shutter key is operated during setting of a celestial body photographic mode, a control section 17 allows an imaging section 11 for carrying out photographing for a plurality of times. The control section 17 allows the imaging section 11 for carrying out the photographing at least once in a way that stars are not photographed as a moving trajectory due to the movement of the stars. An image processing section 13 carries out image processing of adding image components of the stars, existing in the other photographed images to the photographed image photographed, in this way. Thus, the photographic apparatus generates images, obtained by carrying-out photographing under a long time exposure in a state with the stars made to halt. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a technique for obtaining an image in which a moving object assumed as a subject is captured in advance.

  In recent years, imaging apparatuses of a type that capture an image by converting an image into an electrical signal using an imaging element such as a CCD have been widely used. Even with such a photographing apparatus, it is possible to photograph a subject that emits weak light more clearly by increasing the exposure time.

  A moving object whose positional relationship is changed with respect to the photographing apparatus is photographed as a locus of movement of the object by increasing the exposure time, and its shape cannot be visually recognized. Thus, in order to take an image so that the shape of the object can be viewed with a long exposure, the object must be stopped when viewed from the imaging device. For this reason, in photographing a celestial body, the photographing apparatus is rotated in accordance with the rotational movement of the celestial body.

  The rotation of the imaging device is usually performed by attaching the imaging device to an astronomical telescope or the like attached to the equatorial mount and rotating the telescope around the polar axis manually or by a motor at the same speed as the rotation of the earth. It is. Even if such a telescope is not used, in order to rotate the photographing apparatus so that the celestial body is stopped, another dedicated facility is actually required. In addition, in order to properly rotate the photographing apparatus, for example, in an equatorial mount, it is necessary to set the polar axis parallel to the rotation axis of the earth.

As described above, conventionally, photographing with a long exposure without causing the celestial body to be a moving locus has been performed by preparing a dedicated facility and setting the facility accurately. For this reason, the restriction | limiting for performing the imaging | photography was large. From this, it is considered very meaningful to make it easier to obtain an image obtained by such shooting.
JP 2003-323625 A Japanese Patent Laid-Open No. 2002-220098 Japanese Patent Laid-Open No. 5-260362

  The subject of this invention is providing the imaging device which can produce | generate the image obtained by photographing long time exposures in the state which stopped moving objects, such as a celestial body.

  The image capturing apparatus of the present invention is to capture an image by converting an image into an electrical signal by an image sensor, and assumes an image capturing unit that captures an image by exposing the image sensor to a specified exposure time and an object as a subject in advance. A shooting control unit that automatically causes the imaging unit to shoot a first exposure time during which the moving object is not shot as a moving trajectory and a predetermined second exposure time when shooting of the moving object is instructed; A second image obtained by photographing with the second exposure time by the photographing means on the image component of the moving object in the first image obtained by photographing with the first exposure time. And an image processing means for adding an image component by the moving object.

  The program of the present invention has a function for realizing the means included in the photographing apparatus.

  According to the present invention, first and second images are captured at a first exposure time and a predetermined second exposure time, respectively, in which a moving object assumed as a subject is not captured as a movement trajectory. Image processing is performed to add the image component due to the moving object in the second image to the image component due to the moving object. By adding such an image component, the first image can be photographed by making the exposure time longer. The first image is taken with a moving object such as a celestial body stopped. For these reasons, it is possible to generate an image obtained by shooting for a long time with a moving object such as a celestial body stopped.

  When at least one of the first and second images is automatically photographed, it is possible to reduce the number of operations that the user should perform. For this reason, high convenience is obtained for the user, and an image to be generated can be obtained more easily.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a diagram illustrating a configuration of an imaging apparatus according to the present embodiment.
As shown in FIG. 1, this imaging device captures an image formed by an optical system by converting it into an electrical signal using an image sensor such as a CCD, and converts the electrical signal into digital data for output. Unit 11, a memory 12 that can store a captured image output by the imaging unit 11 in the form of digital data, an image processing unit 13 that can perform image processing on the captured image, and an image processing unit 13 A display unit 14 for displaying an image output by the user, a data output unit 15 for outputting the image, an input unit 16 having various keys to be operated by the user, and an operation performed by the user from the input unit 16. The control part 17 which receives the information shown and performs the whole control is comprised.

  The optical system included in the imaging unit 11 includes, for example, a lens group (an optical system) including a zoom lens and a focus lens that are arranged to be movable in the optical axis direction, a plurality of sensors for detecting their positions, and It has a diaphragm and the like. Other than that, a plurality of motors for moving the zoom lens and the focus lens, an aperture actuator for opening and closing an aperture, a shutter actuator for opening and closing a mechanical shutter, a controller for driving them, and an image sensor A driving circuit for driving the image signal, a processing circuit for performing various processes on the electric signal output from the image sensor and converting it to digital data, an encoding circuit for encoding the digital data, and the like. Thereby, the encoded data is stored in the memory 12.

  The input unit 16 includes, for example, a power key, a first mode changeover switch for recording / reproduction mode setting, a second mode changeover switch for normal / astrophotography mode setting when the recording mode is set, a shutter key, and an exposure time change. And a plurality of keys such as a change key, a menu key, a cross key, a focus key, and a zoom key, a CPU that detects a change in the state thereof, and outputs an operation signal corresponding to the change to the controller 17 It has become. There are two types of focus keys and zoom keys, respectively.

  The image processing unit 13 decodes digital data (captured image) encoded and stored in the memory 12 and performs image processing. When outputting the digital data to the data output unit 15, the digital data is output to the data output unit 15 without performing decoding and image processing. In addition, digital data that has not been encoded is input from the imaging unit 11 and output to the display unit 14, thereby displaying a shootable image by operating the shutter key.

  The control unit 17 controls the entire photographing apparatus by generating and sending a command to be sent to the imaging unit 11 and the image processing unit 13 based on an operation signal input from the input unit 16. The time interval (exposure time) for opening and closing the shutter is specified by the command.

  As described above, when the recording mode is set, the user can set either the normal mode or the astrophotography mode as the sub mode. The normal mode is a mode in which shooting is performed according to the contents set before operating the shutter key. In astronomical photography, the light emitted by stars and the like is very faint, so it is common to shoot for long exposures. In long exposure shooting, depending on the exposure time, the position of the star is moved while it is exposed, and the movement trajectory is captured. The astronomical photography mode is a virtual image (when shooting for a long period of time by rotating the photographing device at the same speed as the rotation of the celestial body from the image obtained by actual photographing, regardless of the exposure time) (Hereinafter referred to as “virtual image”). The image processing unit 13 performs image processing for generating the image.

  By generating such a virtual image, the user can obtain an image that has been taken for a long time by appropriately using the dedicated equipment without using a dedicated equipment such as an equatorial mount. become. For this reason, very high convenience is obtained for the user.

  FIG. 2 is a diagram illustrating a functional configuration of the image processing unit 13. The image processing unit 13 includes a stationary object recognition unit 13a, a star pattern recognition unit 13b, a center point calculation unit 13c, a movement angle calculation unit 13d, a light amount integration unit 13e, and a constellation image creation unit 13f. The functions of these units 13a to 13f will be specifically described with reference to the explanatory diagrams of FIG.

  When the user operates the shutter key to instruct shooting when setting the astrophotography mode, the control unit 17 instructs the imaging unit 11 to shoot an image that is exposed by opening the shutter for the exposure time set by the user. Let Before and after taking the image, the image is taken with an exposure time at which the celestial body is not taken in the form of a moving locus. In FIG. 2, an image captured by exposure for an exposure time set by the user corresponds to an open captured image P3. An image captured before capturing the captured image P3 corresponds to the captured image P1 at the start time, and an image captured after capturing the captured image P3 corresponds to the captured image P2 at the end time.

  4 to 6 are diagrams for explaining examples of the captured image P1 at the start time, the captured image P2 at the end time, and the open captured image P3, respectively. In the photographed image P3, a celestial body (star) is photographed as a movement locus by long-time exposure. The images to which OB is attached in FIGS. 4 to 6 are taken still object images (for example, buildings) that have not been moved.

  The stationary object recognition unit 13a receives the captured images P1 and P2 read from the memory 12, and compares them to recognize an object whose shape and position do not change between them as a stationary object. . The recognition of the object is performed on a target having a predetermined size (area) or more. This avoids recognizing the North Star NS as a stationary object. The recognition result is passed to the star pattern recognition unit 13b.

  By comparing the captured images P1 and P2, the star pattern recognition unit 13b changes its position, and the relative positional relationship (pattern) changes between other objects whose positions have changed. Recognize an unoccupied object as a star (celestial body). For each image, the position information of the object recognized as a star, the captured images P1 and P2 from which the stationary object recognized by the stationary object recognition unit 13a is removed are passed to the center point calculation unit 13c.

  The center point calculation unit 13c selects two or more objects from the objects recognized by the star pattern recognition unit 13b as stars, and superimposes the captured images P1 and P2 received from the recognition unit 13b for each selected object. In the form, a line segment connecting the two positions of the object is created, and further a perpendicular bisector of the line segment is created. Thereby, a point where a plurality of perpendicular bisectors intersect is obtained as a center point with the star as the center of rotation.

  FIG. 7 is a diagram for explaining a center point specifying method. In FIG. 7, as in FIGS. 4 to 6, stars captured at different positions in the captured images P <b> 1 and P <b> 2 are distinguished by the presence or absence of filling in the same outer shape.

  In FIG. 7, the straight line passing through the north star NS is a vertical bisector, and the straight line perpendicular to the vertical bisector connects the same stars α and β whose positions are different when the captured images P1 and P2 are captured. . The center point calculation unit 13c creates a straight line connecting different positions according to the shooting time of the same star for a plurality of stars having different positions at the time of shooting, creates a perpendicular bisector of the straight line, and creates the created vertical The center point is accurately specified by obtaining the intersection of the bisectors. The position information of the specified center point, the captured images P1 and P2 obtained by removing the stationary object from the recognition result of the stationary object recognition unit 13a, and the like are passed to the movement angle calculation unit 13d.

  As shown in FIG. 8, the moving angle calculation unit 13d creates two straight lines that connect different positions and center points depending on the shooting time of the same star, with respect to stars with different positions at the time of shooting. The angle formed by the straight line, that is, the angle (movement angle) by which the star rotates around the center point is calculated. The movement amount, the position information of the center point, and the captured images P1 and P from which the stationary object is removed from the recognition result of the stationary object recognition unit 13a are passed to the light amount integrating unit 13e.

  Since the stars rotate, stars with different positions on the captured images P1 and P2 are photographed as moving trajectories that draw an arc in the photographed image P3. The light amount integrating unit 13e extracts an arc drawn by a star on the captured image P3, and for each extracted arc, whether or not the angle of the straight line connecting the two ends of the arc and the central point matches the movement angle. By determining, an arc (star) whose angle matches the movement angle is further extracted.

  The arc finally extracted in this manner is an arc drawn by the stars reflected in the captured images P1 and P2. By extracting such an arc, the light amount integrating unit 13e also recognizes the image area where it exists. The image area is shared by each of the captured images P1 to P3, and corresponds to a portion indicated by 901 in FIG. Since the star rotates, its outer shape is arcuate. The arcs finally extracted are all within the image area 901.

  After the arc is finally extracted, the amount of light (image component) is integrated for each arc, and the integrated amount of light is obtained from, for example, one of the captured images P1 and P2 received from the movement angle calculation unit 13d. The target is given in the form added to the light quantity of the corresponding star in the target captured image. More specifically, for example, for each pixel expressing an arc, the amount of light is calculated by calculating a subtraction value obtained by subtracting the value of a pixel located in the vicinity of the arc from the value, and accumulating the calculated subtraction value. This is done by calculating the calculated value. The accumulated value is given in the form of normalizing the value of the pixel representing the corresponding star in the target photographed image and distributing it according to the normalized value. Accordingly, in consideration of the state in which the star is photographed in the photographed image P1 or P2, the star image component present in the open photographed image P3 is given to the star image component. In this way, image components are given so that they can be felt naturally.

  The light amount integrating unit 13e passes the captured image given the integrated light amount, the position information of the image region 901, and the like to the constellation image creating unit 13f. The creation unit 13f cuts out an image area (range) 902 in a rectangular shape from an image area 901 in the captured image, as shown in FIG. The cut-out image area 902 is displayed on the display unit 14 as a constellation photographed image. Thereby, the display unit 14 displays a photographed image as shown in FIG. An image in the image area 901 corresponds to the virtual image.

  When the integrated light quantity is given as described above, the given light quantity varies depending on the arc angle viewed from the center point. Even if the stars are the same in brightness, the amount of light given varies depending on the angle of the arc. The fluctuation causes a dark star to become brighter than a brighter star, and disturbs the brightness relationship of the original star. In order to eliminate the cause, in this embodiment, the image region 901 shown in FIG. 9 is recognized, and the constellation photographed image 902 is cut out from the region 901. The selection of stars to be displayed by recognizing the image area 901 may be performed according to user settings or according to user settings.

  Both the image processing unit 13 and the control unit 17 are actually realized by, for example, a CPU (not shown) executing a program stored in a flash memory or the like. A program that realizes at least one of them may be distributed by being recorded on a recording medium such as a CD-ROM, a DVD, or a removable flash memory. Part or all of the program may be distributed via a communication network such as a public network. In such a case, the user obtains a program and loads it into a photographing device (here, usually including a data processing device such as a personal computer), thereby realizing a photographing device to which the present invention is applied. Can be made. Therefore, the recording medium may be accessible by a device that distributes the program.

  FIG. 3 is a flowchart showing a photographing process when the astronomical photographing mode is set. The photographing process is a process executed when the user operates the shutter key when the astronomical photographing mode is set. The CPU is realized by executing a program stored in a flash memory or the like. Next, the photographing process will be described in detail with reference to FIG.

  First, in step 301, the captured image P1 at the start time. Shooting for obtaining the open shot image P3 and the shot image P2 (FIGS. 4 to 6) at the end time is sequentially performed. In the subsequent step 302, the captured images P1 and P2 are read from the memory 12, and compared with each other, an object whose shape and position do not change is recognized as a stationary object (part). In the next step 303, the recognized stationary object is removed from each of the captured images P1 and P2. After the removal, the process proceeds to step 304.

  In step 304, by comparing the captured images P1 and P2 after removing the stationary object, the position changes between them, and the relative positional relationship (pattern) between the other objects whose positions have changed. ) Is extracted as a star (celestial body). In the next step 305, the captured images P1 and P2 are overlapped, and a line segment (straight line) connecting the positions shown in the extracted stars is created. After the creation, the process proceeds to step 306, where the created perpendicular bisectors are further created, and the intersection of a plurality of perpendicular bisectors is obtained as the center point (FIG. 7). Step 307 then proceeds.

  In step 307, two straight lines connecting the position where the same star is photographed on the captured images P1 and P2 and the center point are created, and the star is rotated around the center point, that is, the center point. An angle (movement angle) is calculated. In the subsequent step 308, an arc drawn by a star on the open image P3 is extracted, and an arc whose straight line connecting the two ends of the arc and the center point matches the movement angle is extracted from the extracted arcs. Further, the light quantity (image component) is integrated for each extracted arc. Recognition of the image area 901 having all the extracted arcs is also performed. After doing so, the process proceeds to step 309.

  In step 309, for example, for any one of the captured images P1 and P2 after the stationary object is removed, the integrated light amount is added to the light amount of the corresponding star in the target captured image. In step 310 which moves to after that, the image area (range) 902 is cut out in a rectangular shape from the image area 901 of the photographed image to which the integrated light quantity is added, and is displayed on the display unit 14 as a constellation photographed image (FIG. 10). . Thereafter, the series of processing is terminated.

  In the present embodiment, the shooting for adding the light amount (image component) of the star is performed only once, but the shooting may be performed a plurality of times. The exposure time for the shooting is set by the user, but the exposure time may be set automatically. The calculation of the movement angle is performed by analyzing the actually captured image, but it may be calculated by measuring the time interval between the imaging start time and the imaging end time.

  The imaging device according to the present embodiment is provided with the image processing device according to the present embodiment. However, the captured images P1 to P3 captured by the imaging device are provided to generate a constellation captured image on another device. You may make it let it. That is, an image processing apparatus that performs image processing as described above may be prepared separately from the imaging apparatus.

It is a figure which shows the structure of the imaging device by this Embodiment. 3 is a diagram illustrating a functional configuration of an image processing unit 13. FIG. It is a flowchart which shows the imaging | photography process at the time of astronomical photography mode setting. It is a figure explaining the picked-up image P1 example at the start time. It is a figure explaining the picked-up image P2 example at the time of completion | finish. It is a figure explaining an example of open photographic image P3. It is a figure explaining the identification method of a center point. It is a figure explaining how to obtain | require the movement angle which the star rotated centering on the center point. It is a figure explaining the image area | region in which the star made into the display object exists. It is a figure which shows the example of a constellation imaging | photography screen.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 Image pick-up part 12 Memory 13 Image processing part 13a Stationary object recognition part 13b Star pattern recognition part 13c Center point calculation part 13d Movement angle calculation part 13e Light quantity integration part 13f Constellation image creation part 14 Display part 16 Input part 17 Control part P1 Start time Captured image P2 Captured image at the end P3 Open captured image

Claims (2)

In an imaging device that takes an image by converting an image into an electrical signal by an imaging device,
Imaging means for capturing the image by exposing the imaging element for a specified exposure time;
Shooting control means for causing the imaging means to shoot at a first exposure time and a predetermined second exposure time when the moving object assumed as a subject is instructed in advance as a moving locus. When,
Obtained by photographing the image component of the moving object in the first image obtained by the photographing means taking the first exposure time with the second exposure time. Image processing means for adding an image component of the moving object in a second image;
An imaging apparatus comprising: A program to be executed by a photographing apparatus that takes an image by converting an image into an electrical signal by an imaging element,
A function of photographing the image by exposing the image sensor to a designated exposure time;
A function of causing a first exposure time during which the moving object is not photographed as a moving locus and a predetermined second exposure time to be photographed when the photographing of the moving object assumed as a subject is instructed in advance;
The image component of the moving object in the first image obtained by photographing with the first exposure time is caused by the moving object in the second image obtained by photographing with the second exposure time. The ability to add image components;
A program to realize

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