Abstract:
A portable content player, a content storage device, and a method of synchronizing content between the portable content player and the content storage device, the method including: generating a first content state list for content stored in the content storage device and a second content state list for content stored in the portable content player; generating an execution list based on the first content state list and the second content state list; and matching the first content state list with the second content state list by executing a synchronization command included in the execution list on content selected to be synchronized. Accordingly, a user can automatically match the content state lists of the portable content player and the content storage device.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of Korean Patent Application No. 2006-108393, filed on Nov. 3, 2006 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference. 
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Aspects of the present invention relate to a portable content player, a content storage device, and a method of synchronizing content between a portable content player and a content storage device, and more particular, to a method and apparatus for editing a content state list of content stored in each of a portable content player and a content storage device and synchronizing the content state lists between the portable content player and the content storage device with respect to content that is selected to be synchronized. 
     2. Description of the Related Art 
     Conventionally, users directly manage all files in portable content players, such as a portable multimedia player (PMP) and a mobile phone. To manage the files, the users search for desired files from a personal computer (PC) that is a mass media storage device. Thereafter, in order to store the found files in a portable content player, the user may connect the portable content player and the PC to each other in a wired/wireless manner, execute a transmission program, and store desired multimedia files in the portable content player. As a result, in order to view a movie using the portable content player, most users must repeatedly perform the above-described procedures. 
     In addition, in order to continue to view multimedia data (e.g., a movie) that was interrupted during a reproduction in a content storage device (e.g., a PC), using a portable content player, the entire movie file must be downloaded from the content storage device to the portable content player, and after the interrupted point of the downloaded movie file is found, a portion subsequent to the interrupted point must be played. 
     SUMMARY OF THE INVENTION 
     Aspects of the present invention provide a method and apparatus to automatically synchronize content state lists between a content storage device and a portable content player by connecting the content storage device and the portable content player to each other. 
     Aspects of the present invention also provide a method and apparatus to synchronize content, whereby content interrupted during reproduction in a content storage device can be continued from the interrupted point in a portable content player. 
     According to an aspect of the present invention, there is provided a method of synchronizing content state lists between a portable content player and a content storage device having a content reproduction function, the method including: generating a first content state list for content stored in the content storage device and a second content state list for content stored in the portable content player; generating an execution list based on the first content state list and the second content state list; and matching the first content state list with the second content state list by executing a synchronization command included in the execution list on content selected to be synchronized. 
     The selected content may be selected to be synchronized by at least one of the portable content player and the content storage device, and the synchronization command included in the execution list may include at least one of an update command of the first and/or second content state list, a transmission command of a whole or a portion of the selected content, and a delete command of the selected content. 
     The second content state list may include a transmission state, a synchronization state, and a reproduction state for each file of the content. 
     The second content state list may further include information on a reproduction-interruption point of the content. 
     According to another aspect of the present invention, there is provided a method of synchronizing content state lists between a portable content player and a content storage device having a content reproduction function, the method including: determining whether content to be reproduced in the content storage device is transmitted; transmitting and storing the content to be reproduced to the portable content player according to the determination; if the content storage device stops reproducing the content, determining whether the content is completely reproduced; and if it is determined that the content is completely reproduced, deleting the completely reproduced content from the portable content player and updating the content state list of the portable content player. 
     The method may further include deleting a reproduced portion of the content and updating the content state list of the portable content player if it is determined that the content is not completely reproduced. 
     The determining of whether the content is transmitted may include determining whether the content to be reproduced in the content storage device is transmitted based on whether the content to be reproduced is content that is selected to be synchronized, wherein the synchronization is selected by at least one of the portable content player and the content storage device. 
     The content state list of the portable content player may include a transmission state, a synchronization state, and a reproduction state of each piece of content. 
     The content state list of the portable content player may further include information on a reproduction-interruption point of content that has not been completely reproduced. 
     According to another aspect of the present invention, there is provided a content storage device having a content reproduction function and performing content synchronization with a portable content player, the content storage device including: a content storage unit to store content; a content state list generator to generate and to update a first content state list with respect to the content stored in the content storage unit; an execution list generator to generate an execution list based on the first content state list and a second content state list of the portable content player; and a synchronization controller to match the first content state list with the second content state list by executing a synchronization command included in the execution list on content selected to be synchronized. 
     If the content is reproduced when the content storage device is connected to the portable content player, the synchronization controller may store the content to be reproduced in the portable content player, wherein the stored content is content that is selected to be synchronized. 
     If the content is completely reproduced, the synchronization controller may delete the completely reproduced content and update the first and second content state lists. 
     The content may be selected to be synchronized from at least one of the portable content player and the content storage device, and the synchronization command included in the execution list may be at least one of an update command of the first and/or second content state list, a transmission command of a whole or a portion of the selected content, and a delete command of the selected content. 
     The second content state list may include a transmission state, a synchronization state, and a reproduction state for each file of the content. 
     The second content state list may further include information on a reproduction-interruption point of content that has not been completely reproduced by the content storage device. 
     According to another aspect of the present invention, there is provided a portable content player capable of synchronizing content with a content storage device having a content reproduction function, the portable content player including: a content storage unit to store content; and a content state list generator to generate and to update a content state list with respect to the content stored in the content storage unit, wherein the content state list is updated by the content storage device with respect to content that is selected to be synchronized when the portable content player is connected to the content storage device. 
     The content may be selected to be synchronized from at least one of the portable content player and the content storage device, and the content state list may include a transmission state, a synchronization state, and a reproduction state for each file of the content. 
     The content state list may further include information on a reproduction-interruption point of content that has not been completely reproduced. 
     The portable content player may reproduce the content from the reproduction-interruption point by referring to the reproduction information. 
     According to another aspect of the present invention, there is provided a method of reproducing content in a first device that was partially reproduced in a second device, the method including: transmitting the partially reproduced content from the second device to the first device; determining a reproduction-interruption point in the partially reproduced content; and reproducing the content from the reproduction-interruption point. 
     According to another aspect of the present invention, there is provided a method of synchronizing content state lists between a first storage device and a second storage device, the method including: generating a first content state list for content stored in the first storage device and a second content state list for content stored in the second storage device; generating an execution list based on the first content state list and the second content state list; and matching the first content state list with the second content state list by executing a synchronization command included in the execution list on content selected to be synchronized. 
     Additional aspects and/or advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       These and/or other aspects and advantages of the invention will become apparent and more readily appreciated from the following description of the embodiments, taken in conjunction with the accompanying drawings of which: 
         FIG. 1  is a block diagram of a portable content player and a content storage device according to an embodiment of the present invention; 
         FIGS. 2A and 2B  illustrate content state lists of a portable content player and a content storage device according to an embodiment of the present invention; 
         FIG. 3  illustrates an execution list according to an embodiment of the present invention; 
         FIG. 4  is a flowchart illustrating a synchronization method of a content storage device according to an embodiment of the present invention; 
         FIG. 5  is a flowchart illustrating a synchronization method of a portable content player according to an embodiment of the present invention; 
         FIG. 6  is a flowchart illustrating a method of reproducing content based on reproduction information in a portable content player according to an embodiment of the present invention; and 
         FIG. 7  is a flowchart illustrating a case where content is completely reproduced in a state where a portable content player is connected to a content storage device according to an embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
     Reference will now be made in detail to the present embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout. The embodiments are described below in order to explain the present invention by referring to the figures. 
       FIG. 1  is a block diagram of a content storage device  100  (such as a PC) and a portable content player  110  (such as a PMP or a mobile phone) according to an example embodiment of the present invention. Referring to  FIG. 1 , the content storage device  100  includes a content state list generator  101 , a synchronization controller  102 , a content storage unit  103 , a content reproduction unit  104 , and a connection unit  105 . Furthermore, referring to  FIG. 1 , the portable content player  110  includes a content state list generator  111 , a content storage unit  112 , a content reproduction unit  113 , and a connection unit  114 . It is understood that aspects of the present invention disclosed as applying to portable content players  110  are not limited to portable content players  110 , and may be applied to other content storage devices (such as home audio equipment with content storage capabilities or personal computers). 
     The content state list generator  101  of the content storage device  100  generates and/or updates a content state list with respect to content stored in the content storage unit  103 . With respect to each piece of content, the content state list includes, but not limited thereto, a content file name, a synchronization state regarding whether synchronization is set, and a transmission state regarding whether a content file has been transmitted from the content storage device  100  to the portable content player  110 . It is understood that, according to other aspects of the present invention, the content state list may also include additional information, such as a content file size, a content file type, and a reproduction-interruption point referring to a last playback interruption point. 
     For example, the content state list may further include a reproduction state regarding whether the stored content has been reproduced. In addition, after an operation is performed on content in the content storage device  100  (e.g., an operation such as content reproduction or reproduction stop), the content state list generator  101  updates the content state list. Reproduction information, such as the reproduction state and a reproduction-interruption point, may be included in an additional information field of the content state list. 
     The synchronization controller  102  synchronizes the content state list of the content storage device  100  and a content state list of the portable content player  110  with respect to content that is selected to be synchronized according to a synchronization command included in an execution list. The synchronization of the content state lists matches the content state list stored in the content storage device  100  with the content state list stored in the portable content player  110 . 
     The content storage unit  103  stores content that may, for example, be downloaded from an external server via a network or the Internet  130 . The stored content may be reproduced by the content reproduction unit  104 . 
     The connection unit  105  is connected to the portable content player  110  via a wired/wireless connection device  120 . For example, the connection unit  105  may be a Universal Serial Bus (USB) interface, an infrared interface, or a Bluetooth interface. 
     The content state list generator  111  of the portable content player  110  generates and/or updates a content state list with respect to content stored in the content storage unit  112 . With respect to each piece of stored content, the content state list includes, but not limited thereto, a content file name, a synchronization state regarding whether synchronization is set, a transmission state regarding whether a content file has been transmitted from the content storage device  100  to the portable content player  110 , and a reproduction state. Reproduction information including a reproduction-interruption point may be included in an additional information field of the content state list. 
     The content storage unit  112  stores content downloaded from the content storage device  100 . The stored content is reproduced by the content reproduction unit  113 . 
     The connection unit  114  is connected to the content storage device  100  via the wired/wireless connection device  120 . For example, the connection unit  114  may be a USB interface, an infrared interface, or a Bluetooth interface. 
       FIGS. 2A and 2B  illustrate content state lists  200 ,  201 ,  210 , and  211  of the content storage device  100  and the portable content player  110  according to an embodiment of the present invention.  FIG. 2A  illustrates content state lists  200  and  210  before content is synchronized, and  FIG. 2B  illustrates content state lists  201  and  211  after the content is synchronized.  FIG. 3  illustrates an execution list according to an embodiment of the present invention. 
     An additional information field of each content state list may include reproduction information, such as information on a reproduction-interruption point, a play time, a play count, Digital Rights Management (DRM), a license, and a codec of content, although not limited thereto. 
     Referring to  FIGS. 2A ,  2 B, and  3 , a content storage device  100  (e.g., a home PC) storing five pieces of movie content A to E and a portable content player  110  (e.g., a Portable Multimedia Player (PMP)) storing four pieces of movie content A, C, D, and E are described as an example. Furthermore, it is assumed, as an example for purposes of this disclosure, that a user has set synchronization for A, B, C, and E of the content state list  200  of the content storage device  100  and A, C, D, and E of the content state list  210  of the portable content player  110 . 
     Referring to the content state list  210  of the portable content player  110  before synchronization is performed, illustrated in  FIG. 2A , the user has received the content A but has not completely viewed the content A yet. The content C has not been completely received or reproduced. The contents D and E have been completely received and reproduced. The content state list  200  of the content storage device  100  may be understood in the same manner. 
     If the content storage device  100  and the portable content player  110  are connected to each other, the content storage device  100  reads the content state lists  200  and  210  of the content storage device  100  and the portable content player  110 . The content storage device  100  generates the execution list illustrated in  FIG. 3  based on the read content state lists  200  and  210 . 
     Referring to  FIG. 3 , for the content D, it is necessary to update only a synchronization state of the content state list  200  of the content storage device  100 . For the content E, since the portable content player  110  has completely reproduced the content E, it is necessary to delete the content E from the content state list  210 . However, it is understood that, according to other aspects, the content E that has already been completely reproduced may just be omitted from the execution list, rather than deleted. For the content C, it is necessary to retransmit a portion, which has not been transmitted yet, to the portable content player  110 . For the content B, it is necessary to transmit the entire portion of the content to the portable content player  110 . 
     If the execution list illustrated in  FIG. 3  is edited, the content storage device  100  performs synchronization sequentially according to commands included in the execution list. The sequence of synchronization can be set according to the importance of the content, an execution time of each command, the priority of commands, and/or a user&#39;s preference. Thus, after the synchronization is performed, the content state lists  201  and  211  of the content storage device  100  and the portable content player  110  match with each other as illustrated in  FIG. 2B . 
       FIG. 4  is a flowchart illustrating a synchronization method performed by the content storage device  100  illustrated in  FIG. 1 , according to an embodiment of the present invention. Referring to  FIG. 4 , the content storage device  100  sets or initiates synchronization in operation S 400 . It is understood that the synchronization can be set by the portable content player  110  instead of the content storage device  100 . That is, any one of the content storage device  100  and the portable content player  110  can set the synchronization. 
     If the portable content player  110  is connected to the content storage device  100  in operation S 401 , the content storage device  100  reads a content state list from the portable content player  110  in operation S 402 . The content storage device  100  edits an execution list for the content synchronization in operation S 403  and performs the content synchronization according to the execution list in operation S 404 . The content synchronization is sequentially performed in operation S 405  until the content synchronization is performed for all content included in the execution list. 
       FIG. 5  is a flowchart illustrating a synchronization method performed by the portable content player  110  illustrated in  FIG. 1 , according to an embodiment of the present invention. Referring to  FIG. 5 , the portable content player  110  sets or initiates synchronization in operation S 500 . The portable content player  110  determines in operation S 501  whether the portable content player  110  is connected to the content storage device  100 . In operation S 502 , the content storage device  100  performs content management of the portable content player  110  if the portable content player  110  is connected to the content storage device  100  in operation S 501 . That is, the portable content player  110  allows or transmits control rights to the content storage device  100  to control the portable content player  110 . Thus, the content storage device  100  can freely update or delete a content state list and content stored in the portable content player  110 . However, it is understood that according to other aspects, the portable content player  110  may perform content management of the content storage device  100 . 
       FIG. 6  is a flowchart illustrating a method of reproducing content based on reproduction information in the portable content player  110  illustrated in  FIG. 1 , according to an embodiment of the present invention. Referring to  FIG. 6 , a user executes content that has not been completely reproduced in the portable content player  110  in operation S 600 . The content reproduction unit  113  determines in operation S 601  whether reproduction information exists. If reproduction information exists in operation S 601 , the content reproduction unit  113  applies the reproduction information in operation S 604  in order to reproduce the content and reproduces the content based on the reproduction information in operation S 602 . Thus, the portable content player  110  can reproduce the content starting from a point that has not previously been reproduced. If it is determined in operation S 601  that reproduction information does not exist, the content reproduction unit  113  reproduces the content from the beginning of the content in operation S 602 . The reproduction information may be stored in a content state list of the portable content player  110 . 
     The portable content player  110  updates the content state list thereof with respect to the reproduced content in operation S 603 . That is, if the content is completely reproduced, or if reproduction of the content is interrupted, the reproduction information of the content is updated. 
       FIG. 7  is a flowchart illustrating a case where content is completely reproduced in a state where the portable content player  110  illustrated in  FIG. 1  is connected to the content storage device  100  illustrated in  FIG. 1 , according to an embodiment of the present invention. Referring to  FIG. 7 , a user reproduces content in the content storage device  100  in operation S 700  while the portable content player  110  is connected to the content storage device  100 . 
     If synchronization of the content being reproduced is set in operation S 701 , it is determined in operation S 702  whether the content being reproduced is stored in the portable content player  110 . 
     If the content being reproduced is not stored in the portable content player  110  in operation S 702 , the content storage device  100  transmits the content being reproduced to the portable content player  110  in operation S 703 . 
     If the content being reproduced is stored in the portable content player  110  in operation S 702 , it is determined in operation S 704  whether the reproduction of the content has been stopped by the user. 
     If the reproduction of the content has been stopped by the user in operation S 704 , it is determined in operation S 705  whether the content has been completely reproduced. If the content has been completely reproduced in operation S 705 , the portable content player  110  deletes the content in operation S 706 , and updates a content state list thereof in operation S 707 . However, it is understood that according to other aspects, the content that has already been completely reproduced may just be omitted from the execution list, rather than deleted. 
     If the content has not been completely reproduced in operation S 705 , the portable content player  110  updates the content state list thereof with respect to the reproduction-interrupted content in operation S 707 , and the content state list of the portable content player  110  may include reproduction information of the reproduction-interrupted content. Thus, thereafter, the user can reproduce the portion that has not been reproduced based on the reproduction information in the portable content player  110  as illustrated in  FIG. 6 . In this case, the user may delete only the portion of the content that has been reproduced when updating the content state list of the portable content player  110 . 
     As described above, according to aspects of the present invention, content state lists can be automatically synchronized by connecting a portable content player to a content storage device. In addition, for content that has not been completely reproduced in the content storage device, a user can, conveniently, view the content from a point that has not previously been reproduced in the portable content player. 
     Although a few embodiments of the present invention have been shown and described, it would be appreciated by those skilled in the art that changes may be made in this embodiment without departing from the principles and spirit of the invention, the scope of which is defined in the claims and their equivalents.