JP2012058952A - Similar image retrieval device, camera, similar image retrieval method and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a similar image retrieval device, a camera, a similar image retrieval method and a program for enabling selection of a subject with a simple operation.SOLUTION: A similar image retrieval device comprises: a subject selection unit that selects candidate subjects q1-q3 to be candidates of a retrieval reference among subjects displayed on a screen, displays cursors c1-c3 on the images of the candidate subjects, and selects a subject existing at the center of the screen among the candidate subjects as a reference subject; and a similar image retrieval unit that retrieves an image having a subject similar to the reference subject selected by the subject selection unit from a recording medium.

Description

  The present invention relates to a similar image search device, a camera, a similar image search method, and a program for analyzing an image and searching for a similar image.

  A technique for analyzing a photographed image and identifying that a subject is, for example, a person, a building, a mountain, a sea, or the like has progressed, and automatic search for an image has been put into practical use by using this technique. In particular, the progress of technology for recognizing a specific person from a face image is remarkable. For example, there are Patent Document 1 and Patent Document 2 as authentication techniques using face images.

  Various techniques related to a similar image search for searching for another image similar to the type and scene of a photographed image or a person in the image, that is, a so-called similar image have been proposed. Conventionally, when searching for an image with a camera or a personal computer, index image playback is used to display thumbnail images. However, if similar image search is used, an image close to the purpose can be searched by appropriately setting search conditions. For example, in Patent Document 3, a search is performed using a specified attribute item by selecting an attribute item (hue distribution, shooting date, shooting location, composition, subject person) displayed on the screen for a specific search. A search device is disclosed.

JP 2008-233959 A JP 2008-237399 A JP 2007-226536 A

  Even with a portable device such as a camera, if there is a similar image search function, you can quickly find a captured image similar to the current subject from the recording medium, or display an image similar to the similar image to view the captured image. It can be enjoyed and the use of a new camera that has never existed before can be proposed. However, in many cases, when a search is performed on an actual camera screen in which a plurality of subjects are mixed, similar images that are similar to the plurality of subjects currently displayed on the screen are searched, and as a result, A large number of missing images will be searched.

  Therefore, in order to mount a similar image search function in a portable device such as a camera, a subject (for example, a person, a pet, a landscape, etc.) serving as a search reference must be accurately selected on the screen each time. Is required. In particular, it is desirable that the subject can be selected with a simple operation even when the camera is held.

  The present invention has been made in view of such circumstances, and an object thereof is to provide a similar image search device, a camera, a similar image search method, and a program capable of selecting a subject with a simple operation. To do.

  In order to achieve the above object, a similar image search device according to a first aspect of the present invention selects a candidate subject as a search reference candidate from subjects displayed on a screen, and selects the center of the screen among the candidate subjects. A subject selection unit that selects a subject existing in the screen or a subject having a predetermined size or larger on the screen among the candidate subjects as a reference subject, and a subject similar to the reference subject selected by the subject selection unit. A similar image search unit that searches the recording medium for the image having the same.

A camera according to a second aspect includes the similar image search device according to the first aspect, wherein the subject selection unit selects the candidate subject from a live view image and sets the candidate subject on the live view image as a candidate subject. Display the mark.
According to a third aspect of the present invention, the camera according to the second aspect further includes a display control unit that displays an image on the display unit. And displayed together with the live view image.
In the camera according to a fourth aspect, in the third aspect, the display control unit fixes and displays the live view image as the live view image displayed together with the similar image.

  In the similar image search method according to the fifth aspect of the present invention, a candidate subject to be a search reference candidate is selected from subjects displayed on the screen, a mark is displayed on the image of the candidate subject, and the mark is displayed. A subject that exists in the center of the screen among the candidate subjects or a subject that is a predetermined size or larger on the screen among the candidate subjects is selected as a reference subject, and is similar to the selected reference subject. An image having a subject is retrieved from the recording medium.

  A program according to a sixth aspect of the present invention selects a candidate subject as a search reference candidate from subjects displayed on the screen, displays a mark on the image of the candidate subject, and displays the candidate on which the mark is displayed. A subject that exists in the center of the screen among subjects or a subject that is a predetermined size or larger on the screen among the candidate subjects is selected as a reference subject and has a subject similar to the selected reference subject. Retrieve an image from a recording medium.

  According to the first, fifth, and sixth inventions, it is possible to provide a similar image search device, a camera, a similar search method, and a program capable of selecting a subject with a simple operation. Further, according to the second aspect, since the reference subject can be selected by moving the angle of view and zooming with respect to the live view image, it is possible to easily set the reference subject. According to the third aspect, the subject can be selected with a simple operation even when the image recorded on the recording medium is reproduced. Further, according to the fourth invention, even if the direction of the camera is changed, the search image is constant, so that the search image can be viewed with peace of mind.

It is a block diagram which mainly shows the structure of the electric circuit of the camera concerning one Embodiment of this invention. FIG. 6 is a diagram illustrating a case where a candidate subject existing at the center of the screen is selected as a reference subject in the camera according to the embodiment of the present invention. FIG. 6 is a diagram for explaining a case where a candidate subject existing in a size larger than a predetermined size on a screen is selected as a reference subject in the camera according to an embodiment of the present invention. It is a flowchart which shows operation | movement of the imaging | photography mode of the camera concerning one Embodiment of this invention. It is a flowchart which shows the operation | movement of the similar image display process of the camera concerning one Embodiment of this invention. 6 is a flowchart showing an operation of selecting a reference subject of the camera according to the embodiment of the present invention.

  Hereinafter, a preferred embodiment will be described using a camera to which the present invention is applied according to the drawings. A camera according to a preferred embodiment of the present invention is a digital camera, includes an imaging unit, converts a subject image into image data by the imaging unit, and converts the subject image into a main body based on the converted image data. Live view is displayed on the display unit placed on the back of the camera. The photographer determines the composition and the photo opportunity by observing the live view display. During the release operation, image data is recorded on the recording medium. The image data recorded on the recording medium can be reproduced and displayed on the display unit when the reproduction mode is selected.

  FIG. 1 is a block diagram showing a configuration of a camera according to an embodiment of the present invention. A control unit (CPU: Central Processing Unit) 11 operates according to a control program stored in the program / data storage unit 12 and performs overall control of the camera. In the control unit 11, a subject selection unit 11a, a similar image search unit 11b, and an operation detection unit 11c are provided. Since 11a, 11b, and 11c in the control unit 11 are a part of processing executed by the control program, they will be described as functional units included in the control unit 11.

  The subject selection unit 11a selects a candidate subject and a reference subject for searching for similar images. The subject selection unit 11a detects a subject of a person, animal, landscape, food, or color from the screen by using a database stored in the program / data storage unit 12 as a candidate subject. There are two types of selection of the reference subject: a method of selecting a candidate subject at the center of the screen and a method of selecting a candidate subject having a predetermined size or more on the screen.

  The similar image search unit 11b selects an image similar to the reference subject selected by the subject selection unit 11a from images stored in the image storage unit 22 described later. The similar image search uses a known image matching method or the like. The operation detection unit 11c is connected to an operation unit 13 which will be described later, and detects operation states of various operation members such as a cross button and an OK button.

  A program / data storage unit 12, an operation unit 13, and a bus 30 are connected to the control unit 11. The program / data storage unit 12 stores a program to be executed by the control unit 11 as described above, and also stores various data. In addition, a database for searching for a candidate subject and a similar image search is also stored.

The program / data storage unit 12 stores the following pattern as a database for searching for a candidate subject or a similar image. First, as a database for people,
Gender feature pattern of the face,
Long, short, braid, pony and other hairstyle patterns Infants, children, adolescents, middle-aged, old-aged, etc. Facial patterns by generation.

  In addition, as an animal database, shape patterns of animal types such as dogs, cats, rabbits, and mice are stored. As a landscape database, landscape patterns such as mountains, mountains + rivers, mountains + sea, etc. are stored. As a food database, patterns of food types such as apples, mandarin oranges and bananas are stored. As the color database, color types such as red, blue, yellow, and green are stored.

  The operation unit 13 includes various operation members for the user to give instructions to the camera. The various operation members include a power button, a release button, a menu button, an OK button, a cross button, a reproduction button, and the like, and output detection results of operation states of the various operation members to the control unit 11. Note that a search mode, which will be described later, is set in this menu screen by displaying a menu screen with a menu button.

  In addition to the control unit 11 described above, the imaging unit 15, SDRAM (Dynamic Random Access Memory) 16, image processing unit 17, display control unit 18, compression / decompression unit 20, and recording / playback unit 21 are connected to the bus 25. Yes. The imaging unit 15 includes a photographing lens for forming a subject image, an imaging element for converting the subject image into image data, and their processing circuits, a diaphragm and a shutter interposed in the optical path of the photographing lens, and the like. Including. The image data generated by the imaging unit 15 is output to the bus 25.

  The SDRAM 16 is an electrically rewritable volatile temporary storage memory, and is used for temporary storage of image data output from the imaging unit 15. The image processing unit 17 performs various kinds of images such as digital amplification (digital gain adjustment processing) of digital image data, white balance, color correction, gamma (γ) correction, contrast correction, live view display image generation, and moving image generation. Perform processing.

  The compression / decompression unit 20 is a circuit for compressing image data of still images and moving images temporarily stored in the SDRAM 16 by a compression method such as JPEG or TIFF, and decompressing the data for display. Note that image compression is not limited to JPEG or TIFF, and other compression methods can be applied.

  The display control unit 18 causes the display unit 19 to display a live view display during shooting, a REC view display during release, and a playback image during playback. Further, based on an instruction from the subject selection unit 11a, a cursor indicating a displayed candidate image is displayed. Furthermore, the similar image searched by the similar image search part 11b is also displayed. The display unit 19 is connected to the display control unit 18 and includes a display such as a liquid crystal monitor or an organic EL disposed on the back surface of the main body of the camera 10. The display control unit 18 controls the display screen to display a predetermined screen. Is displayed.

  The recording / playback unit 21 stores the image data compressed by the compression / decompression unit 20 in the image storage unit 22 and reads out the image data of the captured image stored in the image storage unit 22. The read image data is expanded by the compression / expansion unit 20, and an image is reproduced and displayed on the display unit 19 based on the expanded image data. The image storage unit 22 is connected to the recording / reproducing unit 21 and is a recording medium for image data that can be built in or loaded into the digital camera body. A captured image is recorded in the image storage unit 22.

  Next, a method for selecting a reference subject from candidate subjects when the search mode is set in the present embodiment will be described with reference to FIGS. As described above, there are two types of methods for selecting the reference subject from the candidate subjects in the present embodiment. The first method is a method of selecting a candidate subject at the center of the screen as a reference subject. The second method is a method of selecting a candidate subject having a predetermined size or larger as a reference subject on the screen.

  FIG. 2 is a diagram sequentially illustrating screens in the case where selection by the first method, that is, a candidate image at the center of the screen is used as a reference subject. FIG. 2A shows a live view image displayed on the display unit 19. A camera mode 51 is displayed on the upper left of the screen 100. In this example, “Live” indicates that the live view image is being displayed. Is displayed.

  In the screen 100 of FIG. 2A, a person (child) p1, an animal (dog) p2, and a car p3 are recognized as candidates as subjects. Note that the car p3 is recognized as having color (in this example, blue) and is one of the candidate subjects. The candidate subject is determined by the subject selection unit 11a based on the subject database stored in the program / data storage unit 12. Further, when the subject selection unit 11a recognizes these p1 to p3, the cursors c1 to c3 are displayed at these positions on the screen 100. That is, a cursor c1 for displaying the person p1, a cursor c2 for displaying the animal p2, and a cursor c3 for displaying the car p3 are displayed. In addition, a center mark 54 indicating the center of the screen is displayed at the approximate center of the screen 100.

  In the screen 100 shown in FIG. 2A, the candidate subjects (p1 to p3) are not located on the center mark 54. When the user moves the camera to the left in this state, the position of the cursor c1 of the person (child) p1 can be made to substantially coincide with the center mark 54 as shown in FIG. If they are substantially matched, the person p1 is selected as the reference subject, and at this time, the live view image is fixed and becomes the reference image.

  When the reference subject is determined, the similar image search unit 11 b searches for a similar image from the captured images stored in the image storage unit 22. In the example shown in FIG. 2, since the person p1 is the reference subject, a similar image is searched based on the “face” criterion. As shown in FIG. 2C, the retrieved similar images 56 are displayed as thumbnail images and displayed in a row at the lower side of the screen as a similar image sequence 55. The numbers described in the similar image 56 shown in FIG. 2C indicate frame numbers. In addition, a cursor 57 is displayed on the similar image row 55, and the cursor 57 can be slid left and right by a cross button.

  When the cursor 57 is slid and one of the similar images 56 is selected and designated by the OK button or the like, the live view display is interrupted as shown in FIG. 2D, and the designated similar image is displayed on the screen. 100 is enlarged and displayed. Since the live view display is interrupted and the mode is changed to the playback mode, “Play” indicating the playback mode is displayed as the camera mode 51. A frame number 58 is displayed on the upper right of the screen 100. In the example shown in FIG. 2D, the frame number “53” is displayed.

  In addition, the subject selection unit 11a recognizes a candidate subject from the currently displayed reproduction image and displays a cursor. That is, in the example of FIG. 2D, cursors c1 and c2 indicating adults q1 and q2, a cursor c3 indicating sun q3, and a cursor c4 indicating food q4 are displayed. The sun q3 is recognized as having a color (in this example, red) and is one of the candidate subjects.

  In the similar image sequence 55, the same face-based search image as the search image in FIG. 2C is displayed. A pointer 60 is displayed at the center of the screen.

  In the display of FIG. 2D, when the cursor c4 indicating the food q4 is moved by the cross button of the operation unit 13 with the pointer 60, the reference subject is replaced with the food q. FIG. 2E shows a display in which the similar image search unit 11b searches for a “food” reference similar image. In this state, the frame number “53” is reproduced and displayed, and a similar image searched on the basis of food is displayed in the similar image sequence 55.

  In this way, by setting the search mode, it is possible to search for similar images as shown in FIGS. 2C to 2F from one to the next and enjoy the search result image. Since this search display is similar to surfing the Internet, it is referred to as photosurfing in this specification.

  When the user finishes the search mode, the user only has to perform the first release, that is, half-press the release button. As a result, as shown in FIG. It returns and the live view screen is also fixed. When the live view display is resumed, the similar image displayed during the live view display is displayed in the similar image column 55. In the example of FIG. 2F, the similar images in the similar image sequence 55 in FIG. 2C immediately before the live view display is interrupted are displayed.

  In this way, the first method can easily select the reference subject simply by changing the camera direction and positioning the candidate subject in the center of the screen even during live view display. In particular, even a device without a touch panel can select the reference subject. When the reference subject is selected, the live view image is fixed, so that the search image becomes constant even when the camera is changed, and the search image can be viewed with peace of mind.

  Next, a second method for selecting a candidate subject, that is, a method for selecting a candidate subject having a predetermined size or larger on the screen as a reference subject will be described with reference to FIG. FIG. 3A shows a state where live view display is performed, as in FIG. In this state, when the user approaches the person (child) p1 or zooms in, the person p1 becomes larger and the cursor c1 also becomes larger as shown in FIG. 3B.

  When the size of the person p1 on the screen as the candidate subject becomes larger than a predetermined size, the person p1 is designated as the reference subject, and the similar image search unit 11b captures the image stored in the image storage unit 22 on the “face” basis. Search for similar images from images. The retrieved similar image 56 is displayed on the lower side of the screen 100 as a similar image sequence 57 as shown in FIG. Similar to FIG. 2C described above, the live view image (reference image) is fixed.

  A cursor 57 is displayed on the similar image row 55, and a similar image can be designated by operating the cross button and the OK button. When a similar image is designated, the live view display is interrupted, and the similar image is reproduced and displayed largely on the screen 100 as in FIG. Since the following operations are the same as when the reference subject is selected by the first method, detailed description thereof is omitted. Also in the second method, when the release button is pressed halfway, the camera returns to the shooting mode, the fixation is released, and the live view display is resumed.

  In this way, in the second method, the size of the subject can be increased by approaching the subject and changing the angle of view with respect to the live view image, or by zooming, and the reference subject can be selected by a simple method. can do. In particular, even a device without a touch panel can select the reference subject. Similarly to the first method, when the reference subject is selected, the live view image is fixed, so that the search image remains constant even when the camera is changed, and the search image can be viewed with peace of mind.

  Next, the operation in the present embodiment will be described with reference to the flowcharts shown in FIGS. When the flow of the shooting mode shown in FIG. 4 is entered, first, a live view image is displayed (S1). Here, based on the image data acquired by the imaging unit 15, the display control unit 18 performs live view display on the display unit 19. The user can determine the composition and the photo opportunity by observing the live view display.

  Once the live view image display is performed, it is next determined whether or not the search mode is selected (S3). As described above, the search mode is set on the menu screen, and in this step, it is determined whether or not this search mode is set.

  If the result of determination in step S3 is that search mode has been selected, then similar image display processing is performed (S5). Here, a candidate subject is selected, a reference subject is selected from the candidate subjects, a similar image is searched based on the selected reference subject, and the search result is displayed as a similar image sequence 55. Detailed operation of the similar image display processing will be described later with reference to FIG.

  If the similar image display process is performed or if the result of determination in step S3 is that search mode has not been selected, it is next determined whether or not a power-off operation has been performed (S7). Here, the operation detection unit 11c determines the operation state of the power button, which is one of the operation units 13. If the result of this determination is that a power-off operation has been performed, the power-off process is performed, and then the shooting mode is terminated.

  If the result of determination in step 7 is that a power-off operation has not been performed, it is next determined whether or not a release operation has been performed (S9). Here, the operation detection unit 11c determines the operation state of the release button, which is one in the operation unit 13. If the result of this determination is that release operation has not been performed, processing returns to step S1. On the other hand, when a release operation is performed, a photographing process is performed (S11). Here, various photographing operations such as AE processing, AF processing, imaging and recording of image data are executed. When the photographing process is performed, the process returns to step S1.

  Next, the similar image display processing in step S5 will be described using the flowchart shown in FIG. If the flow of the similar image display process is entered, it is first determined whether or not the similar image display is the first (S21). Here, it is determined whether or not the similar image display process of step S5 is executed for the first time in the flow of the photographing mode shown in FIG. At the start of the shooting mode, it is determined Yes here.

  If the result of determination in step S21 is that the similar image display is not the first, that is, if it is the second time or later, it is next determined whether or not the reference image is a live view image (S41). In the example shown in FIG. 2C, a reference subject is selected from the live view images, and the live view image at this time is handled as the reference image. In step S41, a reference subject is selected from the live view image instead of the reproduced image as shown in FIG. 2C, and it is determined whether or not the live view image at this time is used as the reference image.

  If the result of determination in step S41 is that the reference image is a live view image, it is next determined whether or not the live view image has changed (S43). Here, the live view image based on the image data acquired by the imaging unit 15 is compared with the reference image based on the live view image to determine whether there has been a change.

  If the result of determination in step S43 is a change in the live view image, or if the result of determination in step S21 is the first similar image display, next, a reference subject is selected (S23). Here, the candidate subject is searched from the image, and when the candidate subject exists, the cursors c1 to c3 are displayed and it is determined whether or not the reference subject exists. Choose as. Detailed operation of this reference subject selection will be described later with reference to FIG.

  Once the reference subject is selected in step S23, an image similar to the reference subject is searched for (S25). Here, the similar image search unit 11b searches the images stored in the image storage unit 22 for an image similar to the selected reference subject according to the search criteria.

  If similar images are searched in step S25, it is next determined whether or not there are similar images (S27). Here, the determination is made based on the result of the similar image search in step S25. If no similar image is found as a result of this determination, only the reference image is displayed on the screen 100 (S37). When the reference image is displayed, the process returns to the original flow.

  On the other hand, if a similar image is found as a result of the determination in step S27, it is next determined whether or not the reference image is a live view image (S29). As described above, the reference image may be a live view image or a reproduction image of an image stored in the image storage unit 22. In this step, it is determined which image is the image.

  If the result of determination in step S29 is that the reference image is a live view image, then the reference image is fixed (S45). Here, the live view image is fixed when a similar image is searched, and the update of the live view image is interrupted. The fixed timing is not limited to this, and may be a time when a reference subject is selected or a timing for displaying a similar image.

  If the reference image is fixed in step S45 or if the result of determination in step S29 is that the reference image is not a live view image, then the reference image and similar image are displayed (S31). Here, for example, as shown in FIG. 2C, the reference image is displayed large on the screen 100, and the similar image sequence 55 is displayed below the reference image.

  If the reference image and the similar image are displayed in step S31, or if the result of determination in step S41 or step S43 is No, it is next determined whether or not a similar image is selected on the screen (S33). . Since the user can select a similar image desired to be viewed while moving the cursor 53, in this step, it is determined whether or not the similar image has been selected by operating an OK button or the like.

  If the result of determination in step S33 is that a similar image has not been selected, it is next determined whether or not a first release operation has been performed (S35). When the photographer performs the shooting preparation operation, the first release operation, that is, the half-press operation of the release button is performed. Therefore, in this step, the first release switch is turned on by the half-press operation of the release button. judge.

  If the result of determination in step S35 is that the first release operation has not been made, processing returns to step S31. On the other hand, when the first release operation is performed, the search mode is ended, the process returns to the original flow, and the normal shooting mode is executed as described in FIG.

  If the result of determination in step S33 is that a similar image has been selected, the selected similar image is then enlarged and displayed (S47). Here, the selected similar image is read from the image storage unit 22, and is enlarged and displayed on the screen 100, for example, as shown in FIG.

  Once the similar image has been enlarged and displayed, it is next determined whether or not a candidate subject has been detected (S49). When the similar image is enlarged and displayed in step S47, the subject selecting unit 11a detects the candidate subject in the enlarged similar image. In this step, it is determined whether the subject selection unit 11a has detected a candidate subject. If the result of this determination is that no candidate subject has been detected, processing returns to step S33.

  On the other hand, when a candidate subject is detected as a result of the determination in step S49, the candidate subject is displayed (S51). Here, for example, as shown in FIG. 2D, the cursors c1 to c4 indicating the candidate subjects are displayed.

  Once the candidate subject has been displayed, it is next determined whether or not the reference subject has been selected (S53). Here, when the image is a live view image, it is determined whether the reference subject is selected by the first method or the second method described above. If the image is a reproduced image, it is determined whether the reference subject has been selected depending on which candidate subject has been moved. If the reference subject is selected as a result of this determination, the process returns to step S25 to search for a similar image and display the similar image as shown in FIG. On the other hand, if the reference subject has not been selected, the process returns to step S33.

  Next, detailed operation of the reference subject selection in step S23 will be described using the flowchart shown in FIG. If the flow for selecting the reference subject is entered, first, the shape and color in the screen are extracted and compared with the database (S61). Here, the subject selection unit 11a analyzes the image in the screen, extracts the shape and color, and compares it with the subject search database stored in the data of the program / data storage unit 12.

  Subsequently, a candidate subject is detected (S63). Here, it is detected whether there is a subject that matches these patterns for the five types stored in the database: person, animal, landscape, color, and food. For example, in the example shown in FIG. 2A, a person (child), blue (blue in the car in FIG. 2A), and animal (dog) are detected as candidate subjects from the live view image. In the example shown in FIG. 2D, a person (man and woman), landscape (sun), and food (apple) are detected as candidate subjects from the reproduced image.

  Once the candidate subject is detected, it is next determined whether or not there is a candidate subject (S65). Here, it determines based on the detection result in step S63. If the result of this determination is that there is no candidate subject, processing returns to step S7 (see FIG. 4).

  On the other hand, if the result of determination in step S65 is that there is a candidate subject, the cursor is then superimposed on the candidate subject (S67). Here, for example, as shown in FIG. The cursors c1 to c3 are displayed at the position of the candidate subject according to the size of the candidate subject. Next, it is determined whether the display image is a live view image (S68). If it is a live view image (S68 Yes), the process proceeds to step S69.

  If the cursor is superimposed on the candidate subject, it is next determined whether or not there is a candidate subject in the center area of the screen (S69). As described above, the reference subject determination method includes the first and second methods. Here, the reference subject determination is performed by the first method. For example, as shown in FIG. 2B, it is determined whether or not there are candidate subjects p1 to p3 at the center mark 54 position.

  If the result of determination in step S69 is that there is a candidate subject in the center area of the screen, then the candidate subject in the screen center is selected as the reference subject (S71). Here, for example, as shown in FIG. 2B, a person (child) p1 is selected as the reference subject. When the reference subject is selected, the flow returns to the original flow.

  If the result of determination in step S69 is that there is no candidate subject in the center area of the screen, it is next determined whether or not there is a candidate subject of a predetermined size or larger (S73). Here, the reference subject is determined by the second method. For example, as shown in FIG. 3B, it is determined whether or not the subject has a predetermined size or more. The predetermined size or more is, for example, about 5% or more of the screen size in terms of area. However, the present invention is not limited to this, and the size may be larger or smaller as long as it can be regarded as a main subject.

  If the result of determination in step S73 is that there are candidate subjects that are larger than a predetermined size, it is next determined whether or not there are a plurality of candidate subjects (S75). If the reference subject selection criterion is a predetermined size or more, a plurality of candidate subjects may be selected. Here, it is determined whether a plurality of candidate subjects have been selected.

  If the result of determination in step S75 is that there are more than one, the largest candidate subject is selected as the reference subject (S77). On the other hand, if the result of determination is that there are not a plurality, the candidate subject is selected as a reference subject (S79). Therefore, when there is a candidate subject of a predetermined size or larger, the largest candidate subject is set as a reference subject, and when there is only one candidate subject of a predetermined size or larger, the candidate subject is set as the reference subject. And When the reference subject is selected in steps S77 and S79, the process returns to the original flow.

  On the other hand, if the display image is not a live view image in step S68 (S68 No), that is, if the display image is a playback image, it is determined whether the pointer has been moved to the candidate subject (S81). If the result of this determination is that it has been moved (S81 Yes), the candidate subject to which the pointer has been moved is selected as the reference subject (S83). Then, it returns to the original flow. If the pointer is not moved (No in S81), the process jumps to step S83 and returns to the original flow.

  As described above, in one embodiment of the present invention, a subject that exists in the center of the screen among candidate subjects in the subject image, or a subject that has a predetermined size or larger on the screen among candidate subjects. The reference subject is selected. Therefore, the subject can be selected with a simple operation. In particular, even if a search is executed on a screen where a plurality of subjects are mixed, the reference subject is accurately selected. As a result, a group of similar images can be searched and photo surfing can be enjoyed. .

  In particular, when the subject existing in the center of the screen is selected as the reference subject, the reference subject can be selected by a simple operation of adjusting the direction of the camera, for example. Further, when selecting a candidate subject having a predetermined size or larger as a reference subject on the screen, the reference subject can be selected by a simple operation such as zooming of the camera. In any method, even in a device without a touch panel, the reference subject can be easily selected.

  In one embodiment of the present invention, a candidate subject in the center of the screen or a candidate subject of a predetermined size or more is selected as a reference subject selection method. However, when searching for similar images, a reference subject is selected. Any method can be used as long as it can be selected. In one embodiment of the present invention, five types of patterns of person, animal, landscape, food, and color are stored as a database when searching for a candidate subject or searching for similar images. However, this pattern is not limited to this, and other patterns such as flowers and miscellaneous goods may be used.

  Further, in the embodiment of the present invention, the example in which the similar image search device is mounted on the camera has been described. However, the present invention is not limited to this, and when storing images in a personal computer or the like and playing back and enjoying these images Can also be applied. In the embodiment of the present invention, similar images are searched and displayed in both the live view display mode and the playback display mode, but only one of them may be displayed.

  Furthermore, in the embodiment of the present invention, the digital camera is used as the photographing device. However, the camera may be a digital single lens reflex camera or a compact digital camera, such as a video camera or a movie camera. It may be a camera for moving images, or may be a camera built in a mobile phone, a personal digital assistant (PDA), a game device, or the like.

  The present invention is not limited to the above-described embodiments as they are, and can be embodied by modifying the constituent elements without departing from the scope of the invention in the implementation stage. In addition, various inventions can be formed by appropriately combining a plurality of components disclosed in the embodiment. For example, you may delete some components of all the components shown by embodiment. Furthermore, constituent elements over different embodiments may be appropriately combined.

DESCRIPTION OF SYMBOLS 11 ... Control part, 11a ... Subject selection part, 11b ... Similar image search part, 11c ... Operation detection part, 12 ... Program / data storage part, 13 ... Operation part, 15 ... Imaging unit, 16 ... SDRAM, 17 ... Image processing unit, 18 ... Display control unit, 19 ... Display unit, 20 ... Compression / decompression unit, 21 ... Recording / reproduction , 22... Image storage unit, 51... Camera mode, 54... Center mark, 55.
57 ... Cursor, 58 ... Frame number, 100 ... Screen

Claims (6)

A candidate subject that is a candidate for a search criterion is selected from subjects displayed on the screen, and a subject that exists in the center of the screen among the candidate subjects or a predetermined number or more of the candidate subjects on the screen is selected. A subject selection unit that selects a subject of a size as a reference subject,
A similar image search unit that searches a recording medium for an image having a subject similar to the reference subject selected by the subject selection unit;
A similar image retrieval apparatus comprising: The similar image search device according to claim 1 is provided.
The camera, wherein the subject selection unit selects the candidate subject from a live view image and displays a mark on the candidate subject on the live view image. A display control unit for displaying an image on the display unit;
The camera according to claim 2, wherein the display control unit displays the similar image retrieved from the recording medium by the similar image retrieval unit together with the live view image.   The camera according to claim 3, wherein the display control unit fixes and displays a live view image as the live view image displayed together with the similar image. Select a candidate subject to be a search criterion candidate from the subjects displayed on the screen, display a mark on the image of the candidate subject,
Select a subject that exists in the center of the screen among the candidate subjects displayed with the mark or a subject that is a predetermined size or larger on the screen among the candidate subjects as a reference subject,
Retrieving an image having a subject similar to the selected reference subject from the recording medium;
A similar image search method characterized by the above. Select a candidate subject to be a search criterion candidate from the subjects displayed on the screen, display a mark on the image of the candidate subject,
Select a subject that exists in the center of the screen among the candidate subjects displayed with the mark or a subject that is a predetermined size or larger on the screen among the candidate subjects as a reference subject,
Retrieving an image having a subject similar to the selected reference subject from the recording medium;
A program that causes a computer to execute.