Abstract:
In one aspect, the present invention is directed to a method and an apparatus for organizing digital media, particularly digital photos, using face recognition. According to a first aspect of the present invention, a computer-based method for organizing digital photos comprises: extracting objects of interest from a plurality of photographs; cropping said plurality of photographs to generate images of isolated objects of interest; applying a recognition algorithm to determine the similarity of isolated objects of interest with a reference; displaying a plurality of objects arranged as a function of the determined similarity; and receiving user input to associate said objects with a particular classification.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application is a Divisional of and claims the benefit under 35 USC §120 of Nonprovisional application Ser. No. 10/734,259 filed on Dec. 15, 2003 now U.S. Pat. No. 7,822,233, which claims the benefit under 35 U.S.C. §119 of U.S. Provisional Application No. 60/519,639 filed on Nov. 14, 2003. The entire contents of all of the above applications is hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     This invention relates to a computer-based technique for organizing media, and more particularly to a method and apparatus for organizing digital media based on face recognition. 
     2. Description of the Related Art 
     Digital cameras have gained popularity in recent in years, in part due to the flexibility offered by electronic image storage. By storing digital photos on a personal computer, laptop, a network accessible server, etc., users are able to organize, edit, and share their images. Also, as compared to film-based photography, the user of a digital camera can typically assess the quality of a photo immediately, without spending time and money on a set of prints containing at least some low quality images. In view of the widespread transition from analog to digital photos, service providers and vendors have introduced a variety of products, web-based services, and software tools, including processing software tools for editing digital photos and services for remotely ordering prints and other products (e.g., holiday cards) using the user&#39;s picture file(s). File browsing and media viewing software typically allows users to organize and view their photos in electronic Albums, for example organized in folders based on dates (e.g., October 2003) and events (e.g., Ski Trip—January 2002). Considering that the average user has hundreds of photos, such tools offer a convenient way to organize and retrieve photos. 
     Despite these existing products and services, the inventors of this application has found that the need exists for more-advanced techniques and software tools for conveniently and quickly organizing digital photos. 
     SUMMARY OF THE INVENTION 
     In one aspect, the present invention is directed to a computer-based method and apparatus for organizing digital media, particularly digital photos, using recognition techniques. According to a first aspect of the present invention, a computer-based method for organizing digital photos comprises: extracting objects of interest from a plurality of digital photos; cropping the plurality of digital photos to generate images of isolated objects of interest; applying a recognition algorithm to determine the similarity of isolated objects with a reference; displaying a plurality of objects of interest arranged as a function of the determined similarity; and receiving user input to associate the objects and corresponding digital photos with a particular classification. 
     According to a second aspect of the present invention, an apparatus for organizing digital photos comprises: an object detecting unit for detecting objects of interest in a plurality of digital photos and cropping the plurality of digital photos to generate images of isolated objects of interest; a recognition unit for applying a recognition algorithm to determine the similarity of isolated objects with a reference; a display output for displaying a plurality of objects arranged as a function of the determined similarity; and a user input for receiving user input to associate the objects and corresponding digital photos with a particular classification. 
     In accordance with one embodiment of the present invention, the operations of applying the recognition algorithm and displaying image objects as a function of determined similarity are repeated as objects are classified. In one embodiment, the objects are faces. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Further aspects and advantages of the present invention will become apparent upon reading the following detailed description and with reference to the appended drawings, in which: 
         FIG. 1  is a block diagram of a system for organizing digital media according to an embodiment of the present invention; 
         FIG. 2  is a block diagram illustrating in more detail aspects of the media organizing and processing unit of the system illustrated in  FIG. 1  according to an embodiment of the present invention; 
         FIG. 3  is an exemplary graphical user interface display screen associated with media organizing and browsing according to an embodiment of the present invention; 
         FIG. 4  is a flow diagram illustrating operations performed for recognition-based organization of digital photos in accordance with an embodiment of the present invention; 
         FIG. 5  is an exemplary graphical user interface display screen associated with importing images for face recognition-based organizing of digital photos in accordance with an embodiment of the present invention; 
         FIG. 6  is an exemplary graphical user interface display screen associated with displaying face images sorted by similarity to model face images to assist the user in organizing digital photos; and 
         FIGS. 7A-7C  illustrate an exemplary digital photo presentation using the results of face recognition in accordance with an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the present invention are more specifically set forth in the following description with reference to the appended figures. Generally, the present invention is directed to a computer-based method and system for organizing media, and more particularly to a computer-based system and method for organizing digital photos in accordance with objects detected and recognized in the digital photos. In one implementation described in detail below, a group of digital photos is organized by detecting and recognizing faces appearing therein. 
     The present invention may be implemented as a computer-executed software product, installed on a user&#39;s personal computer (or some other suitable device) to allow the user to organize a collection of digital photographs in accordance with the people appearing in the photographs. In one embodiment, a system for organizing and processing photographs is provided with at least one face recognition algorithm, which determines the similarity of faces appearing in a collection of photographs to at least one face in a model folder. The present invention may be implemented to allow a user to set up folders for different people, find similar faces to a face or faces in these folders, and add photographs to the “people folders” based on detected similarity. One implementation of the present invention is described in which face detection and recognition are used as tools (e.g., as a software plug-in for a photo storing/processing application) for facilitating digital photo organization (e.g., allowing the user to organize hundreds or photographs based on people in a few minutes). Although the following description details a specific work-flow with reference to specific display screens shown in the figures, it should be recognized that many variations are possible. 
       FIG. 1  is a block diagram of a system for organizing digital photos according to an embodiment of the present invention. The system  10  illustrated in  FIG. 1  includes the following components: an image input device  20 ; a media organizing and processing unit  30 ; a printing unit  40 ; a user input unit  50 ; and a display  60 . Operation of and functional interaction between the components illustrated in  FIG. 1  will become apparent from the following description. 
     The image input device  20  provides digital image data representing a photograph. The image input device  20  may be one or more of any number of devices for providing digital image data derived from photographic film or a digital camera, e.g., a recording medium (a CD-R, floppy disk, etc.) or a network connection. The image input device  20  may be a scanner for scanning images recorded on paper or film, e.g., including CCD sensors for photoelectronically reading R (red), G (green), and B (blue) image information from film, frame by frame. The media organizing and processing unit  30  receives digital image data from the image input device  20  and performs recognition-based media organizing in a manner discussed in detail below. Although not a focus of this application, the media organizing and processing unit  30  may perform other functions, such as image compression, editing, color/density correction, etc., in accordance with commands received from the user input device  50 . A user views graphical user interface (GUI) display screens and other information (including photos) output by the media organizing and processing unit  30  on a display  60  and inputs commands and other information to the media organizing and processing unit  30  via the user input device  50 . In the embodiment illustrated in  FIG. 1 , the user input device  50  includes a keyboard  52  and a mouse  54 . The printing unit  40  selectively receives image data from the media organizing and processing unit  30  to generate prints. 
       FIG. 2  illustrates details of the media organizing and processing unit  30  for performing recognition-based media organizing of digital photos according to an embodiment of the present invention. As shown in  FIG. 2 , the media organizing and processing unit  30  according to this embodiment includes: an image memory  32 , which stores digital image data; a face detection/cropping unit  34 ; a face recognition unit  36 ; and a media organizing control unit  38 . Although the various components of  FIG. 2  are illustrated as discrete elements, such an illustration is for ease of explanation and it should be recognized that certain operations of the various components may be performed by the same physical device, e.g., by a microprocessor of a user&#39;s personal computer. Operation of the components of the media organizing and processing unit  30  in  FIG. 2  will next be described with reference to  FIGS. 3-7 . 
       FIG. 3  is an exemplary GUI display screen  100  output by the media organizing control unit  38  to the display  60  in accordance with one implementation of the present invention. The GUI display screen  100  illustrated in  FIG. 3  allows the user to initiate and control various media organizing and viewing functions provided by the media organizing control unit  38 . The display screen  100  includes a category list  102  of general media organizing categories, including “dates,” “events,” “places,” and “people,” which constitute digital photo albums. Accordingly, the user may select from this category list  102  to organize digital photos and/or access previously-organized digital photos based on these general categories. For example, the user may select “dates” from the category list  102  to organize and/or browse digital photos organized by date. Likewise, the user may select “events” to organize and/or browse digital photos organized by the event at which they were taken (e.g., vacation  2002 , graduation  2003 , etc.). Furthermore, in accordance with principles of the present invention, the user may select “people” to organize digital photos based on the faces appearing therein, using face recognition, and browse digital photos previously organized based on people. Each general category in the category list  102  will typically include multiple folders, which may further contain sub-folders. Thus, under the “people” category, separate folders may be set up for “family,” “classmates,” “work colleagues,” etc., each containing a sub-folder for an individual member of the particular category. 
     The GUI display screen  100  further includes a display window  110  for viewing photos. In the example of  FIG. 3 , the display window  110  displays an index view of photos in a selected folder. This may be initiated by selecting a “show all photos” button  114 . Also, the user may view cropped faces appearing in photos of the selected folder in the display window  110  by selecting a “show faces” button  116 . Extracting and cropping faces from a group of digital photos will be described in greater detail below. An individual photo may be viewed by clicking on the desired photo in the display window  110  and selecting a “photo viewer” tab  112 . In accordance with principles of the invention, the face recognition-based organization may be initiated by selecting a “search faces” button  118  from the display screen  100 . The display screen  100  includes various additional icons and menus for performing related functions, such as ordering prints, sharing photos, editing images, etc. 
       FIG. 4  is a flow diagram illustrating functions performed by the media organizing and processing unit  30  to organize digital photos based on face recognition in accordance with an embodiment of the present invention. Initially, digital images are imported for organization in one or more of the digital photo album categories in list  102  (step S 212 ). These digital images may be imported from existing folders (e.g., stored in image memory  32 ) or input via external media, such as the image input device  20 .  FIG. 5  illustrates an exemplary GUI display screen  300  for importing digital photos, which allows the user to select folders or individual images to be imported. The face detection/cropping unit  34  detects faces in the imported digital photos and crops out the face(s) from the digital photos to obtain a view of the individual faces in the imported digital photos (S 214 ). The face detection/cropping unit  34  may utilize a face detection algorithm such as that disclosed in U.S. patent application Ser. No. 10/440,173, titled “Method and Apparatus for Red-Eye Detection,” which is herein incorporated by reference. Other techniques for face detection may also be utilized. 
     The user is able to control whether to automatically detect and crop out faces for images being imported, e.g., by selecting the “automatically detect faces” button  306  on the GUI display screen  300  shown in  FIG. 5 . In other words, the face detection/cropping unit  34  may perform face detection and cropping in the background as the user is performing other functions. If a user decides not to detect faces at the time of importing the photos, the user can select a “detect faces” menu option (not shown) at any time. Again, the face detection/cropping unit  34  may operate in the background with low priority, meaning that other tasks (operations) can be performed while the detection is being done. The detect faces operation need only be performed once for each imported digital photo. After face detection and cropping has been performed for a set of imported digital photos, the user may select a “show faces” button  116  of the GUI display screen  100  to view the detected faces in the display window  110 . 
     At any time after face detection and cropping for a group of imported digital images has been executed, the user may initiate face recognition-based organization of such digital photos.  FIG. 6  is an exemplary graphical user interface display screen associated with displaying face images sorted by similarity to model face images to assist the user in organizing digital photos. Although the face detection/cropping unit  34  extracts faces appearing in digital photos, it can be seen from  FIG. 6  that the face view may show an area larger than the face (face area  414 ) so that the user can view the entire face and surrounding features, such as the head, neck, and hat (if worn). This results in a better viewing image as compared to just viewing the face itself. 
     The user may select a folder  402  under the “people” category in GUI display screen  400  (in category list  102 ) or create a new person folder (S 216 ). To serve as a basis for face recognition, the selected folder or new folder must contain at least one face image. The user may drag and drop any of the faces from an “unknown” display window portion  406  (i.e., displaying faces from imported digital photos that have not been associated with a particular person folder). Once the user has selected the person folder for matching with “unknown” faces (which serves as a comparison model), the face recognition unit  36  applies face recognition to determine similarity of unknown faces to the selected model (S 218 ). 
     A previously classified image of a person may appear substantially different than the same person in other photographs (e.g., due to different angles, poses, photographing positions, aging, etc.). Thus, a preferred embodiment of the present invention utilizes a face recognition algorithm that provides good results under such conditions. One implementation of the present invention utilizes the face recognition algorithm described in the U.S. Patent application titled “Method and Apparatus for Object Recognition Using Probability Models” filed on even date herewith and which is hereby incorporated by reference. Such a face recognition algorithm has also been described in U.S. Provisional Application No. 60/519,639 filed Nov. 14, 2003, which has been incorporated herein by reference in its entirety. After the face recognition unit  36  obtains a similarity measure for each unknown face, the media organizing control unit  38  sorts the unknown faces by similarity measure (most similar to least similar) and outputs an updated “unknown” display window portion  406  ( FIG. 6 ) showing the unknown faces in sorted order (S 220 ). Using this updated display  400 , the user is able to drag and drop one or more of the sorted unknown faces from the “unknown” display window portion  406  into a model display window portion  408  (step S 222 ). If, after the user has dragged and dropped an unknown face into the model display window portion  408 , there are additional unknown faces (S 224 ), the face recognition algorithm is repeated (S 218 ). In other words, the face recognition unit  36  in accordance with one embodiment of the present invention may output different results depending on the images in the model folder  402 , particularly because as additional faces from different conditions are added to the folder  402 , the accuracy of the recognition improves and the recognition results change. Thus, the arrangement of unknown faces in display window portion  406  is updated as the user drags and drops unknown faces into the model display window portion  408  to improve the user&#39;s ability to quickly and reliably associate unknown faces and the corresponding digital photos with the model folder  402 . When the media organizing control unit  38  determines that the people-based media organizing is complete (S 224 ), the process ends. Using the above-described technique, the user is able to organize even hundreds of photos in a short time based on the people appearing therein. 
     Having detected and recognized faces in digital photos, the resulting information can be used in accordance with principles of the present invention to enhance photo viewing presentations. For example, as shown in  FIG. 7A , the folder name corresponding to a face in a digital photo can be displayed along with the digital photo. This may be done during a “slide presentation” of a group of digital photos. Furthermore, as shown in  FIG. 7B , the name of a classified face may be displayed when the user moves the cursor over a displayed face. Furthermore, by clicking on the person&#39;s name, the media organizing control unit  38  may initiate a zooming function to zoom in on the detected person as shown in  FIGS. 7B-7C . More than one person can be specified to initiate a panning display between multiple faces in the digital photo being viewed. 
     Although embodiments of the present invention have been described above in the context of face-recognition, principles of the present invention may be applied to organizing digital photos based on other types of objects that can be detected and recognized in the digital photos. The invention having thus been described, it should be apparent that various other modifications are possible without departing from the spirit and scope of the present invention. For example, depending on accuracy, digital photos may be automatically grouped in people folders based on face recognition, providing the user with the option of re-assigning incorrectly grouped photos.