Abstract:
A content filtering method for selecting a desired piece of content from a plurality of pieces of content includes the steps of associating additional information about each piece of content and reduced image data representing the piece of content with the piece of content and registering the additional information and the reduced image data in a table; retrieving a piece of content having a highest level of coincidence with the additional information from the table by using the additional information corresponding to the reduced image data specified by a user as a search key; and presenting the reduced image data about the retrieved piece of content to the user.

Description:
CROSS REFERENCES TO RELATED APPLICATIONS 
       [0001]    The present invention contains subject matter related to Japanese Patent Application JP 2006-308594 filed in the Japanese Patent Office on Nov. 15, 2006, the entire contents of which are incorporated herein by reference. 
       BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to a filtering method for retrieving a desired piece of content from many pieces of content, a filtering apparatus by the filtering method, and a recording medium having a filtering program recorded thereon. 
         [0004]    2. Description of the Related Art 
         [0005]    Widespread use of personal computers and broadband provides an increasing number of opportunities to view or browse many pieces of content to users. For example, it is possible to acquire content data about music, movies, dramas, and novels by using download services or through online shopping or to make use of Web pages or blogs publicized by personals or images photographed by personals with digital cameras by using personal computers. 
         [0006]    However, an increase in the number of pieces of content makes difficult for the users to browse all the pieces of content. In addition, it is necessary to prepare a method of easily retrieving pieces of content desired by the users. 
         [0007]    Under such circumstances, for example, the following methods are proposed: 
       (A) Collaborative Filtering 
       [0008]    For example, when a book is purchased through online shopping, purchase histories of other users are utilized to introduce other books purchased by the users who purchased the book. 
       (B) Tag 
       [0009]    Tag information is added to pieces of content. A tag added to a specified piece of content is used as a keyword to retrieve other pieces of content. 
         [0010]    In the case of (A), users can find other related pieces of content (books) only by selecting a piece of content (a book to be purchased). In the case of (B), since the tag is used as a keyword, it is easy to determine why the other pieces of content are selected. 
         [0011]    Documents in related art include, for example, Japanese Unexamined Patent Application Publication No. 2002-334257 and Upendra Shardanandand Pattie Maes, 1995, “Social Information Filtering: Algorithms for Automating Word of Mouth”, ACM CHI&#39;95 Proceedings. 
       SUMMARY OF THE INVENTION 
       [0012]    However, in the case of (A), if a piece of content desired by the user is not selected, there is no method of retrying the selection, that is, there is no method of retrieving other pieces of content by trial and error. In addition, it is difficult to determine any correlation between a selected piece of content and what is selected. 
         [0013]    In the case of (B), since the number of associated pieces of content is increased as the abstractness of a tag is increased, it is difficult to refine desired pieces of content. In addition, it is necessary to perform two steps: “selecting a piece of content” and “selecting a tag”. 
         [0014]    It is desirable to easily filter out (select) a desired piece of content from many pieces of content. 
         [0015]    According to an embodiment of the present invention, a content filtering method for selecting a desired piece of content from a plurality of pieces of content includes the steps of associating additional information about each piece of content and reduced image data representing the piece of content with the piece of content and registering the additional information and the reduced image data in a table; retrieving a piece of content having a highest level of coincidence with the additional information from the table by using the additional information corresponding to the reduced image data specified by a user as a search key; and presenting the reduced image data about the retrieved piece of content to the user. 
         [0016]    According to another embodiment of the present invention, a recording medium includes a computer-executable filtering program for selecting a desired piece of content from a plurality of pieces of content. The filtering program includes the steps of associating additional information about each piece of content and reduced image data representing the piece of content with the piece of content and registering the additional information and the reduced image data in a table; retrieving a piece of content having a highest level of coincidence with the additional information from the table by using the additional information corresponding to the reduced image data specified by a user as a search key; and presenting the reduced image data about the retrieved piece of content to the user. 
         [0017]    According to another embodiment of the present invention, a content filtering apparatus for selecting a desired piece of content from a plurality of pieces of content includes registering means for associating additional information about each piece of content and reduced image data representing the piece of content with the piece of content and registering the additional information and the reduced image data in a table; retrieving means for retrieving a piece of content having a highest level of coincidence with the additional information from the table by using the additional information corresponding to the reduced image data specified by a user as a search key; and presenting means for presenting the reduced image data about the retrieved piece of content to the user. 
         [0018]    According to the present invention, associated pieces of content are dynamically updated each time a new piece of content is selected. In addition, selecting an arbitrary piece of content from the updated pieces of content causes pieces of content associated with the selected piece of content to be dynamically updated. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0019]      FIG. 1  shows an example of a display screen during browsing according to an embodiment of the present invention; 
           [0020]      FIG. 2  shows an example of a display screen during filtering according to an embodiment of the present invention; 
           [0021]      FIG. 3  shows an example of a display screen during editing according to an embodiment of the present invention; 
           [0022]      FIG. 4  shows an example of a data table used in the embodiments of the present invention; 
           [0023]      FIG. 5  shows another example of the data table used in the embodiments of the present invention; 
           [0024]      FIG. 6  shows an example of hardware configuration to which the embodiments of the present invention are applicable; 
           [0025]      FIG. 7  is a flowchart showing an example of a routine according to an embodiment of the present invention; and 
           [0026]      FIG. 8  is a flowchart showing an example of part of a routine according to an embodiment of the present invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS 
       [0027]    In the following description, reduced images with which pieces of content, such as music, documents, motion pictures, or still images can be recalled are called “entries”. For example, an embodiment of the present invention is realized in the following manner: 
         [0000]    (1) Multiple pieces of content are displayed in a list including entries.
 
(2) The number of lists and the number of lists that are actually displayed are optional.
 
(3) The multiple lists can have arbitrary themes.
 
(4) During editing, an editing area is displayed.
 
(5) The entries can be edited in the editing area and in the multiple displayed lists. For example, the entries can be copied, deleted, moved, or added.
 
(6) For example, double-clicking an entry displays and plays back the pieces of content to which the entry is liked.
 
         [0028]    An example of a displayed list during browsing will now be described along with how to operate the displayed list. It is presumed that the list is a chronology in which multiple entries are arranged in time series. Arranging a user&#39;s background, music pieces which the user listened to, comics which the user read, things which the user purchased, affairs of memories, and so on in time series in the chronology can create the user&#39;s personal history reminiscent of old days. 
         [0029]    The entries include, for example, reduced images of the jackets of music CDs, reduced images of leading characters and some scenes in comics, reduced images of purchased things, and reduced images of newspaper articles. 
         [0030]    The chronology is processed by a personal computer owned by the user and is displayed in a display device of the personal computer. Data about displayed pieces of content may be stored in a external server or may be stored in the personal computer owned by the user. 
         [0031]    The chronology is displayed, for example, in a manner shown in  FIG. 1 .  FIG. 1  shows an example of a chronology displayed in a display device of a user. A display screen  10  is divided into a left window (area)  11  and a right window (area)  12 . For example, the right window  12  is about two times larger than the left window  11 . 
         [0032]    Referring to  FIG. 1 , a Search tab  11 S, a Detailed tab  11 D, and an Edit tab  11 E are displayed at the top of the left window  11 . The Search tab  11 S, the Detailed tab  11 D, and the Edit tab  11 E are used for switching between modes. In the example shown in  FIG. 1 , the Search tab  11 S is clicked with, for example, a mouse to be in a search mode. A menu and various input and selection items are displayed in the left window  11 . A desired item can be input or selected from the items with the keyboard or mouse. 
         [0033]    The chronology is displayed in the right window  12 . Accordingly, a vertical numeric division bar (year bar)  12 Y used for dividing the dates in units of years is displayed on the left side of the right window  12 . In the example shown in  FIG. 1 , part of the year bar  12 Y, from the middle of 1973 to the middle of 1976, is displayed. 
         [0034]    A first chronology  21  including the entries (thumbnails) of pieces of content along a theme is displayed on the right side of the year bar  12 Y. In the example shown in  FIG. 1 , the theme of the first chronology  21  is the personal history of the user and music pieces which were released or prevailed in each year in the year bar  12 Y are displayed in the first chronology  21 . 
         [0035]    An age bar  21 A is displayed on the left side of the first chronology  21 . The age bar  21 A is adjacent to the year bar  12 Y and is parallel to the year bar  12 Y. Ages of the user, from the middle of two year to the middle of five year, are displayed in the age bar  21 A with reference to the date of birth of the user set in advance. The age bar  21 A is associated with the divided years in the year bar  12 Y. An entry  75 A indicating a music piece (a piece of content) which was released at the time when the user was four years old is displayed near the “four year” in the age bar  21 A. The entry  75 A may be a reduced image of the jacket of a music CD on which the corresponding music piece is recorded. 
         [0036]    A title  21 T (“the personal history” in the example shown in  FIG. 1 ) of the first chronology  21  and a Close (Clear) button  21 C used for closing the first chronology  21  are displayed at the top of the first chronology  21 . 
         [0037]    A second chronology  22  is displayed on the right side of the first chronology  21 . The second chronology  22  is displayed in a manner similar to that of the first chronology  21  (the age bar  21 A is not displayed in the second chronology  22 ). Music pieces typical of each year are registered in the second chronology and the entries of the registered music pieces are displayed in the second chronology  22 . Specifically, in the example shown in  FIG. 1 , an entry  73 A indicating a hit tune in 1973 is displayed at a vertical position corresponding to “1973” in the year bar  12 Y and an entry  74 A indicating a hit tune in 1974 is displayed at a vertical position corresponding to “1974” in the year bar  12 Y. The same applies to the subsequent years in the year bar  12 Y. 
         [0038]    A title  22 T (“Collection of American music” in the example shown in  FIG. 1 ) of the second chronology  22  and a Close (Clear) button  22 C used for closing the second chronology  22  are displayed at the top of the second chronology  22 . 
         [0039]    The same applies to display of the third and subsequent chronologies. When the many chronologies are displayed, horizontal scrolling of the right window  12  allows the chronologies to be sequentially displayed in the right window  12 . 
         [0040]    A vertical scroll bar  12 V and top and bottom scroll buttons  12 S are displayed on the right side of the right window  12 . Operating the vertical scroll bar  12 V or the top and bottom scroll buttons  12 S with the mouse allows the year bar  12 Y and all the chronologies (the first chronology  21  and the second chronology  22  in the example shown in  FIG. 1 ) to be vertically scrolled in synchronization with each other. 
         [0041]    If an arbitrary entry in the entries displayed in the first chronology  21  or the second chronology  22  is double-clicked with the mouse, the piece of content corresponding to the entry is selected and played back. For example, if the entry  75 A indicating a music piece is double-clicked, the music piece corresponding to the entry  75 A is selected and played back. 
         [0042]    The user may make the created chronologies public on a network. In such a case, the user can obtain a comment from another user or can compare the created chronology with the chronology created by another user (can display the chronology created by the other user at the position of the second chronology  22 ) to share memories with other users, thereby feeling a sense of nostalgia. 
         [0043]      FIG. 2  shows an example of the display screen  10  when the pieces of content in the second chronology  22  are filtered out. Specifically, in the example shown in  FIG. 2 , the Close button  21 C in the first chronology  21  is clicked in the display state in  FIG. 1  to close the first chronology  21 . As a result, the second chronology  22  is displayed at the position of the original first chronology  21 . It is presumed that the content of the chronology  22  is available or is provided over the Internet or the like. 
         [0044]    A filtering box  31  used for editing is displayed in a blank area in the right window  12 . Although not shown, the filtering box  31  is displayed when [Filtering box] is selected from the menu or a filtering box iron is selected. 
         [0045]    The filtering box  31  includes a Favorite area  31 A and a Recommended area  31 B. Any entry displayed in the chronology  22  can be registered (copied) in the Favorite area  31 A. The registration is realized by right-clicking or dragging-and-dropping the entry with the mouse. In the example shown in  FIG. 2 , an entry  74 A displayed in the chronology  22  and an entry  77 A that is not within the display screen  10  in  FIG. 2  are registered in the Favorite area  31 A. 
         [0046]    After the entries are registered in the Favorite area  31 A, entries associated with the registered entries are determined on the basis of conditions described below and the determined new entries are registered in the Recommended area  31 B. In the example shown in  FIG. 2 , since the entries  74 A and  77 A are registered in the Favorite area  31 A, entries  78 A, . . . ,  77 B associated with the entries  74 A and  77 A are registered in the Recommended area  31 B. 
         [0047]    Specifically, the entries of the pieces of content selected by the user are displayed in the Favorite area  31 A. The pieces of content associated with the piece of content selected by the user are automatically selected and the entries of the selected pieces of content are displayed in the Recommended area  31 B. 
         [0048]    Any entry registered in the Favorite area  31 A can be deleted at any time. The entries in the Recommended area  31 B are also deleted in conjunction with the deletion of the entry registered in the Favorite area  31 A. In other words, the entries in the Recommended area  31 B are dynamically updated in conjunction with the entries in the Favorite area  31 A. 
         [0049]    Clicking a Close button  31 C in the filtering box  31  with the mouse closes the filtering box  31  (clears the display of the filtering box  31 ). However, even if the display of the filtering box  31  is cleared, the information in the filtering box  31 , that is, the entries in the filtering box  31  are held. Accordingly, it is possible for the user to browse the entries in multiple chronologies while checking them and to collectively add the entries to the chronologies later. 
         [0050]    The user can collect favorite pieces of content with reference to the entries of the pieces of content. In addition, the pieces of content associated with the collected pieces of content are also automatically collected. 
         [0051]    Since the entries in the Recommended area  31 B are automatically updated, the user can refine the entries in the Recommended area  31 B, that is, the recommended pieces of content or can delete unnecessary entries while the user sequentially adds new entries to the Favorite area  31 A. The entries registered in the Favorite area  31 A can be used in or added to the chronology  21  or  22  or a chronology newly created in a manner described below. 
         [0052]      FIG. 3  shows how to create and edit a new chronology  23 . In the creation of the chronology  23 , the Edit tab  11 E in the left window  11  is clicked with the mouse to be in an editing mode. A predetermined operation in the left window  11  displays the blank chronology  23  on the right side of the year bar  12 Y in the right window  12 , as shown in  FIG. 3 . Referring to  FIG. 3 , a reference symbol  23 T denotes a title and a reference symbol  23 C denotes a Close button. 
         [0053]    A desired entry, among the entries displayed in the Favorite area  31 A or the Recommended area  31 B in the filtering box  31  displayed in response to the user&#39;s operation, is drag-and-dropped in the chronology  23 . In the example shown in  FIG. 3 , the entry  74 A registered in the Favorite area  31 A is drag-and-dropped in the chronology  23  to copy the entry  74 A to the chronology  23 . The entry  74 A is automatically displayed at the position corresponding to the associated year/date when the entry  74 A is dropped (that is, the mouse button is released) regardless of where the entry  74 A is dragged in the chronology  23 . This is because each entry is displayed at the position corresponding to the associated year/date in the chronology by referring to “date” data associated with the entry, as described below. 
         [0054]    A similar operation can be repeated to make the chronology  23  complete. Entries may be copied or moved from the existing first chronology  21  or second chronology  22  to the chronology  23  or may be copied or moved between the first chronology  21  and the second chronology  22 . 
         [0055]    When an entry in any of the first chronology  21 , second chronology  22 , and chronology  23  is added to the Favorite area  31 A, the entries in the Recommended area  31 B are also updated in accordance with the addition of the entry to the Favorite area  31 A. 
         [0056]    As described above, any entry displayed in the Favorite area  31 A or the Recommended area  31 B in the filtering box  31  can be easily add to either of the first chronology  21 , the second chronology  22 , or the chronology  23 , thus saving the trouble of creating the chronology. 
         [0057]      FIG. 4  shows an example of a data table, a table of chronologies CHRTBL, which the chronology (the first chronology  21 , the second chronology  22 , or the like) displayed in the window  12  has. The table of chronologies CHRTBL has one group for every chronology. Each group includes “Chronology ID”, “Title”, and “Entry IDs”. One line in the table of chronologies CHRTBL corresponds to one chronology in the example shown in  FIG. 4 . 
         [0058]    The “Chronology ID” is an identification code used for identifying a chronology. The “Title” denotes a chronology name given by the user. The “Entry IDs” are identification codes used for identifying the entries displayed in each chronology. The “Entry ID” will be described in detail below with reference to  FIG. 5 . 
         [0059]    In the example shown in  FIG. 4 , the chronology in the first line has the “0005” as the “Chronology ID”, “Personal History” as the “Title”, and “0066, 0072, 0077, . . . ” as the “Entry IDs”. The chronology in the first line is displayed on the basis of the above information. 
         [0060]    The table of chronologies CHRTBL may include a descriptive text describing the chronology in detail, a creator, an update time, a create time, and so on, in addition to the above data, for every chronology. The table of chronologies CHRTBL may be prepared in an external server. 
         [0061]      FIG. 5  shows an example of a data table of entries, that is, a table of entries ENTTBL. The entries in a chronology serve as introductory parts for playing back (playing or displaying) desired pieces of content. The table of entries ENTTBL has one group for every entry. Each group includes “Entry ID”, “Date”, “Title”, “Artist”, “Name of entry file”, “Name of content file”, and “Tags”. One line in the table of entries ENTTBL corresponds to one entry in the example shown in  FIG. 5 . 
         [0062]    The “Entry ID” is an identification code used for identifying an entry and is used in, for example, the table of chronologies CHRTBL, as shown in  FIG. 4 . The “Date” indicates, for example, the date when the piece of content corresponding to the entry is sold. The “Title” indicates the name of the piece of content. 
         [0063]    The “Artist” indicates a performer or creator of the piece of content. The “Name of entry file” indicates the name of an entry file (image file) displayed in the chronology or the filtering box  31 . The “Name of content file” indicates the name of a content file corresponding to the entry and is used when the piece of content is selected and played back. When the piece of content is stored in a storage device in a filtering apparatus (personal computer), the name of the content file includes a path name and a file name. When the piece of content is supplied from, for example, an external server, the name the content file indicates a uniform resource locator (URL), which includes the type of information, a server name, a port number, a folder name, a file name, and so on. 
         [0064]    The “Tags” indicates link information used for linking the entries in the Favorite area  31 A in the filtering box  31  to the entries in the Recommended area  31 B in the filtering box  31 . Specifically, when an entry is registered in the Favorite area  31 A, the “Tags” are used to select the entry corresponding to another piece of content associated with the piece of content of the registered entry and the selected entry is displayed in the Recommended area  31 B. The information in the “Tags” may be automatically extracted from the “Date”, “Title”, or “Artist” described above or may be edited by the user to add a keyword or the like thereto. 
         [0065]    The table of entries ENTTBL may include a descriptive text describing the entry in detail, an image, a motion picture, a sound, link information, and so on, in addition to the above data, for every entry. The table of entries ENTTBL may be prepared in an external server. 
         [0066]      FIG. 6  shows an example of the hardware configuration of a personal computer  100  to which the embodiments of the present invention is applicable. The personal computer  100  has a configuration similar to that of a common personal computer. The personal computer  100  includes a central processing unit (CPU)  101 , a read only memory (ROM)  102 , a non-volatile memory  103 , and a random access memory (RAM)  104 . 
         [0067]    The CPU  101  executes various programs. Basic Input/Output System (BIOS) and basic data executed by the CPU  101  are written in the ROM  102  and the non-volatile memory  103 . The RAM  104  serves as a working memory when the CPU  101  executes the programs. The ROM  102 , the non-volatile memory  103 , and the RAM  104  are connected to the CPU  101  via a system bus  111 . 
         [0068]    A hard disk drive (HDD)  105  serving as a mass storage device is also connected to the system bus  111 . The HDD  105  includes an operating system (OS) operating the personal computer  100  and programs realizing the processing described above. 
         [0069]    A communication interface circuit  106  is further connected to the system bus  111 . The personal computer  100  is connected to an external network  120 , such as the Internet, via the communication interface circuit  106 . A server  130 , which stores the table of chronologies CHRTBL, the table of entries ENTTBL, and various files used by the table of chronologies CHRTBL and the table of entries ENTTBL, is connected to the network  120 . 
         [0070]    The personal computer  100  further includes an audio playback circuit  107  and a display control circuit  108 , which are connected to the system bus  111 . The audio playback circuit  107  performs decoding, for example, in a Moving Picture Experts Group (MPEG) Audio Layer-3 (MP3) format to digital audio data that is supplied, if necessary. The audio playback circuit  107 , then, converts the digital audio data into an analog audio signal and supplies the analog audio signal to a speaker  117 . 
         [0071]    The display control circuit  108  includes a video RAM (not shown) to which display data is supplied. The display data is repeatedly read out at predetermined intervals and the readout display data is converted into a video signal. The video signal is supplied to a display  118  where an image is displayed. A keyboard  112  and a mouse  113  are connected to the system bus  111  as a character input device and a pointing device, respectively. 
         [0072]      FIG. 7  is a flowchart showing an example of a routine  200  for realizing display of a chronology in the window  12 . The routine  200  is provided in the HDD  105 . Only part of the routine  200  which is related to the embodiments of the present invention is shown in  FIG. 7 . 
         [0073]    The routine  200  is executed in the following manner by the CPU  101 . When the execution of the routine  200  is instructed with the keyboard  112  or the mouse  113 , in Step S 201 , the CPU  101  starts the routine  200 . In Step S 202 , the CPU  101  sets various initial settings to display an initial screen in the display  118 . The window  12  in the initial screen may be blank or may be in the final state when the initial screen was previously used. The menu is displayed in the window  11  in the initial screen to wait for input of a processing mode by a user. 
         [0074]    When the user selects display of the chronology on the menu, then in Step S 203 , the CPU  101  acquires data about the “Title” from the table of chronologies CHRTBL, displays the list of the titles of chronologies in the window  12  in accordance with the acquired data, and waits for selection of a chronology. When the user selects the title of a desired chronology from the list of the titles of the chronologies displayed in Step S 203 , then in Step S 204 , the CPU  101  selects all the entry IDs associated with the selected title from the table of chronologies CHRTBL. 
         [0075]    In Step S 205 , the CPU  101  acquires the date, the title, the artist, the name of an entry file, the name of a content file, and the tags associated with each entry ID selected in Step S 204  from the table of entries ENTTBL. In Step S 206 , the CPU  101  displays the chronology including the entries in accordance with the data acquired in Step S 205 . In Step S 207 , the CPU  101  waits for an instruction for the subsequent processing. 
         [0076]    If the user double-clicks the entry in the state in which the chronology is displayed in Step S 206 , the CPU  101  goes from Step S 207  to Step S 211  to determine the content of the instruction in Step S 207 . 
         [0077]    Since the entry is double-clicked in this case, the CPU  101  goes from Step S 211  to Step S 212 . In Step S 212 , the CPU  101  selects the name of a content file associated with the entry ID of the double-clicked entry and plays back the piece of content, for example, a music piece, a motion picture, or a still image. The chronology is displayed in the manner described above. After the playback is terminated, the CPU  101  goes back to Step S 206  to update the display screen and, then in Step S 207 , waits for an instruction for the subject processing. 
         [0078]    If update is instructed when the CPU  101  waits for an instruction in Step S 207 , the CPU  101  goes from Step S 211  to S 213 . In Step S 213 , the CPU  101  executes an update routine  300  described below to display the filtering box  31  with which filtering of the entries is performed. The CPU  101  updates the entries in the Recommended area  31 B in accordance with the result of the filtering. If termination of the update is instructed, the CPU  101  goes back to Step S 206  to update the display screen and, then in Step S 207 , waits for an instruction for the subject processing. 
         [0079]    If another processing, for example, scrolling of the chronology or termination of the routine  200  is instructed when the CPU  101  waits for an instruction in Step S 207 , the CPU  101  goes from Step S 211  to Step S 214  to perform the instructed processing. 
         [0080]      FIG. 8  is a flowchart showing an example of the update routine  300  executed in Step S 213 . Referring to  FIG. 8 , in Step S 301 , the CPU  101  starts the update routine  300  after Step S 211 . In Step S 302 , the CPU  101  determines whether the content of the Favorite area  31 A is updated. For example, the CPU  101  determines whether a new entry is registered in the Favorite area  31 A or whether an existing entry is deleted from the Favorite area  31 A. The CPU  101  may determine whether information concerning a registered entry is updated, for example, whether the “Tags” information concerning a registered entry is updated. 
         [0081]    If the CPU  101  determines that the content of the Favorite area  31 A is updated, then in Step S 303 , the CPU  101  acquires the entry ID of the entry newly registered in the Favorite area  31 A from the table of entries ENTTBL. 
         [0082]    Concurrently, the CPU  101  acquires other data concerning the entry from the table of entries ENTTBL on the basis of the acquired entry ID. Specifically, although the filtering can be performed by using only the tag information, also registering data about the “Title” and the “Date” allows entries having similar titles or entries having close dates to be retrieved. 
         [0083]    In Step S 304 , the CPU  101  retrieves entry IDs having the tag information added to the entry ID acquired in Step S 303  from the table of entries ENTTBL. Specifically, the CPU  101  retrieves entry IDs by using the tag information as a search key. Entries that have been already registered in the Favorite area  31 A may be excluded from the retrieval. A target where entry IDs are retrieved may be set for every chronology, instead of the retrieval from the table of entries ENTTBL. For example, entry IDs may be retrieved from a displayed chronology or may be retrieved from a related chronology. 
         [0084]    In Step S 305 , the CPU  101  displays the entries retrieved in Step S 304  in the Recommended area  31 B. The entries may be arranged in the order of the retrieval (in descending order of the level of coincidence) or may be arranged in units of chronologies to which the entries belong. 
         [0085]    In Step S 306 , the CPU  101  terminates the update routine  300 . If the CPU  101  determines in Step S 302  that the content of the Favorite area  31 A is not updated, the CPU  101  goes from Step S 302  to Strep S 306  to terminate the update routine  300 . 
         [0086]    The entries to be displayed in the Recommended area  31 B are dynamically updated each time the entries registered in the Favorite area  31 A are updated in the manner described above. As a result, the user can adjust the entries to be added to the Favorite area  31 A while confirming the entries displayed in the Recommended area  31 B to collect desired entries. 
         [0087]    In the filtering box  31 , the registration of an entry in the Favorite area  31 A causes entries associated with the registered entry to be retrieved and the retrieved entries are registered in the Recommended area  31 B. The registration can be realized by using the tags of each entry (entry ID) in  FIG. 5 . 
         [0088]    For example, it is presumed that two entries ENT 1  and ENT 2  are registered in the Favorite area  31 A and that the entries ENT 1  and ENT 2  have the following tags added thereto: 
         [0089]    Entry ENT 1 : “Mariah Green” “idol” “oldies” “1974” 
         [0090]    Entry ENT 2 : “Mariah Green” “idol” “American music” Retrieval is performed on the basis of the following search conditions: 
       (1) AND Search 
       [0091]    Entries having all the tags added to the entries ENT 1  and ENT 2 , that is, entries having “Mariah Green”, “idol”, “oldies”, “1974”, and “American music” as the tags are valid. 
       (2) Common Search 
       [0092]    Entries having tags common to the entries ENT 1  and ENT 2 , that is, entries having “Mariah Green” and “idol” as the tags are valid. 
       (3) OR Search 
       [0093]    Entries having any one of the tags added to the entries ENT 1  and ENT 2 , that is, entries having any one of “Mariah Green”, “idol”, “oldies”, “1974”, and “American music” as the tag are valid. 
         [0094]    Of the search conditions, (1) AND search has the toughest search conditions and (3) OR search has the easiest search conditions. Accordingly, for example, the search is performed in the following manner to register the valid entries in the Recommended area  31 B: 
         [0000]    (11) The AND search is performed. If any search result is yielded in the AND search, the yielded search result is registered in the Recommended area  31 B.
 
(12) If the AND search achieve no valid entry, the common search is performed. If any search result is yielded in the common search, the yielded search result is registered in the Recommended area  31 B.
 
(13) If the common search achieves no valid entry, the OR search is performed. If any search result is yielded in the OR search, the yielded search result is registered in the Recommended area  31 B.
 
         [0095]    Alternatively, the search may be refined in the reverse order. Specifically, the search may be performed in the following manner to register the valid entries in the Recommended area  31 B: 
         [0000]    (21) The OR search is performed. If an appropriate number of search results are achieved in the OR search, the search results are registered in the Recommended area  31 B.
 
(22) If too many search results are achieved in the OR search, the common search is performed. If an appropriate number of search results are achieved in the common search, the search results are registered in the Recommended area  31 B.
 
(23) If too many search results are achieved in the common search, the AND search is performed. If an appropriate number of search results are achieved in the AND search, the search results are registered in the Recommended area  31 B.
 
         [0096]    Alternatively, the user may select either of the AND search, the common search, or the OR search. 
         [0097]    According to the embodiments of the present invention, only performing the operation “registration of entries in the Favorite area  31 A” allows candidates for entries to be browsed to be automatically displayed in the Recommended area  31 B, so that the user can easily obtain desired entries. 
         [0098]    The information in the Recommended area  31 B is dynamically updated in response to a user&#39;s operation. Accordingly, if the candidates are excessively refined, some entries can be removed from the Favorite area  31 A to increase the number of candidates displayed in the Recommended area  31 B. If the user wants to refine the candidates, entries can be added to the Favorite area  31 A to reduce the number of candidates displayed in the Recommended area  31 B. 
         [0099]    Since only selecting the entry allows the information in the Recommended area  31 B to be updated, it is not necessary for the user to select tags added to the entry and to be conscious of the tags. 
         [0100]    Since an entry can be registered in the Favorite area  31 A in response to a user&#39;s operation, it is sufficient for the user to mark interested entries during browsing. During editing, the user can collectively add only desired entries to the chronology, among the marked entries. 
         [0101]    Although only the routine  200  and the update routine  300  realizing the embodiments of the present invention are provided in the personal computer  100  in the above description, part of the data, for example, pieces of content having higher playback frequencies may be stored in the personal computer  100 . 
         [0102]    The chronology is exemplified in the above description, for example, alphabetic characters are displayed in the vertical axis of the window  12  and entries, such as affairs, may be classified on the basis of the initial letters of the entries. 
         [0103]    It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and alterations may occur depending on design requirements and other factors insofar as they are within the scope of the appended claims or the equivalents thereof.