JP4403408B2 - Content reproduction system, content reproduction apparatus, and content reproduction method - Google Patents

Description

  The present invention relates to a content playback system, a content playback device, and a content playback method for playing back content stored in a content storage device using a content playback device.

  Conventionally, there is an optical recording medium called MD (Mini Disc; registered trademark). In the MD, compressed audio data and data for error correction are recorded. The MD player reads audio data recorded on the MD, performs error correction on the read audio data, and expands the audio data subjected to error correction to generate a reproduction signal.

  The MD player includes temporary storage means for preventing sound interruption. The buffer includes a read pointer and a write pointer, and outputs the written audio data to the decoder while writing the audio data read from the disk.

  The buffer write bit rate and the read bit rate are controlled to be equal. While the MD player is operating normally, the volume of audio data stored in the buffer is always held at a specified amount. Even when reading of a signal from the disk fails due to dirt or vibration of the disk, the playback sound does not break up until the buffer read pointer catches up with the write pointer (for example, Patent Document 1). .

  In recent years, there is a content reproduction system in which content is stored in a server and this content is reproduced by a client. The client of the content reproduction system is provided with a content reception buffer. In the client, after a predetermined amount of content is stored in the buffer, the reproduction of the content is started. Stable playback is realized by storing the content in the buffer.

  Some conventional music players have a function of setting a playback mode. The playback mode includes “continuous playback mode”, “repeat mode”, “single-track repeat mode”, and the like. “Continuous playback mode” is, for example, a mode in which albums are played back in the order of songs, and playback is stopped when the last song is played. The “repeat mode” is a mode for repeatedly reproducing an album or the like. When the last song is reproduced, the reproduction is repeated from the first song of the album. The “single song repeat mode” is a mode in which one designated song is repeatedly played. The switching of the playback mode is widely used in conventional music playback devices.

Japanese Patent Laid-Open No. 10-149632

  The client performs a process of playing back the content stored in the buffer while storing the content received from the server in the buffer. When such processing is performed, there is a difference between the timing of receiving the content from the server and the timing of reproducing the content. This shift causes a problem that it is not easy to switch the playback mode during content playback.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a content playback apparatus, a content playback system, and a content playback method capable of switching playback modes even during playback of content.

In order to achieve the above-described object, a content playback system according to the present invention communicates with a content storage device having content storage means for storing content whose playback order is determined in advance by playback order information, and the content storage device. Communication means to perform, content to be reproduced next based on reproduction order information and type of reproduction mode, request means for requesting transmission of the content to the content storage device, reproduction means for reproducing the content, content Temporary storage means for temporarily storing the content received from the storage device and outputting the stored content to the playback means at a predetermined speed; and when the playback mode is switched during content playback, Alternatively then select the content to be reproduced, the transmission request of the content to the content storage device Bovine chromatic and a reproduction mode switching means and a content reproduction apparatus having a reproduction mode switching means, the switching of the reproduction mode when the content being reproduced and the content to be reproduced next is stored in the temporary storage means where indicated, then stop receiving content to be reproduced, after the reproduction of contents being reproduced has been completed, selects the next content to be reproduced based on the reproduction mode designated a reproduction order information If the playback mode is instructed when only the content being played back is stored in the temporary storage means, the next content to be played back is selected based on the playback order information and the designated playback mode. To do .

A content playback apparatus that receives content whose playback order is determined in advance by playback order information and plays back the received content, determines content to be played next based on playback order information and playback mode, and Requesting means for making a transmission request, reproducing means for reproducing the content, temporary storage means for temporarily storing the content received from the content storage device, and outputting the stored content to the reproducing means at a predetermined speed, when reproduction mode is switched during the playback of the content, then select the content to be played instead of the request means, e Bei and a reproduction mode switching means for performing a transmission request for the content, the reproduction mode switching means, When the content being played back and the content to be played next are stored in the temporary storage means, switching of the playback mode is indicated. Is when was the then stop receiving content to be reproduced, after the reproduction of contents being reproduced has been completed, to determine the next content to be reproduced based on the reproduction mode designated a reproduction order information When the reproduction mode is instructed when only the content being reproduced is stored in the temporary storage means, the content to be reproduced next is selected based on the reproduction order information and the designated reproduction mode. .

A content playback method of a content playback system comprising a content storage device that stores content whose playback order is determined in advance by playback order information, and a content playback device that plays back the content stored in the content storage device. Next playback based on the playback order information transmitting step for transmitting playback order information from the device to the content playback device, the playback mode setting step for setting the playback mode of the content playback device, and the playback order information and the set playback mode A content selection step for selecting content to be transmitted, a content request step for requesting transmission of the selected content to the content storage device, a content storage step for storing content transmitted from the content storage device in the temporary storage means, and a temporary storage means Play stored content at a specified speed That a regeneration step, when reproduction mode during reproduction of the content has been switched, to select the next content to be reproduced, has a reproduction mode switching step of performing a transmission request of the content to the content storage device, changing a play mode in step, when the switching of the reproduction mode is instructed when the content to be reproduced on the content and the next during playback is stored in the content storage unit, then stop receiving content to be reproduced, during the reproduction After the reproduction of the content is completed, the next content to be reproduced is determined based on the reproduction order information and the designated reproduction mode, and the reproduction mode is selected when only the content being reproduced is stored in the temporary storage means. When switching is instructed, the content to be reproduced next is selected based on the reproduction order information and the designated reproduction mode .

  According to the present invention, when switching of the playback mode is instructed when the content being played back and the content to be played next are stored in the content storage means, reception of the content to be played next is received and played back. After the reproduction of the content in the content is completed, the content to be reproduced next is determined based on the reproduction order information and the reproduction mode of the switching destination, and a transmission request for the content is made to the content storage device. As a result, the playback mode can be switched even while the content is being played back.

  Hereinafter, a content reproduction system 1 to which the present invention is applied will be described with reference to the drawings. FIG. 1 shows a configuration of a content reproduction system 1. The content reproduction system 1 includes a server 2 that stores content, a client 3 that reproduces the content, and a switching hub 4 that relays communication between the server 2 and the client 3. The content reproduction system 1 is connected by a LAN (Local Area Network). This LAN performs communication according to TCP / IP (Transport Protocol / Internet Protocol). In addition, you may use another structure and another communication system as a structure and communication system of the content reproduction system 1. FIG.

  The server 2 includes a content storage unit 21 that stores music content, a playlist storage unit 22 that stores a playlist of music content, a communication unit 23 that communicates with the client 3, and music content that provides a music content providing service. Unit 24 and a system control unit 25 that controls the entire server 2.

  The music content providing unit 24 receives a request from the client 3 and controls the communication unit 23 to transmit data to the client 3. Data requested from the client 3 includes a list of reproduction lists, a reproduction list, music contents, and the like. The reproduction list is a list in which the reproduction order and music information of a plurality of music contents are described.

  The client 3 includes a communication unit 31 that communicates with the server 2, a content request unit 32 that requests content from the server 2, a reception ring buffer 33 that temporarily stores music content received from the server 2, and music A converter 34 that converts content from a digital signal to an analog signal, an amplifier 35 that amplifies the analog music signal, a speaker 36 that outputs the music signal amplified by the amplifier 35 as sound, and an input unit that receives input from the user 37 and a display unit 38. In addition, the client 3 includes a content switching unit 39 to be reproduced next instead of the content requesting unit 32 when the reproduction mode is switched during content reproduction.

  The content requesting unit 32 selects a music content to be reproduced next during reproduction of a certain music content, and requests the selected music content from the server 3. The reproduction order of the music content is described in the reproduction list. The content request unit 32 selects the content to be reproduced next based on the description of the reproduction list and the current reproduction mode. The playback modes include “continuous playback mode”, “repeat mode”, and “single song repeat mode”. When “continuous reproduction mode” is selected, the music contents listed in the reproduction list are requested in order. When “repeat mode” is selected, the reproduction order of the reproduction list is repeated. In the “single song repeat mode”, one piece of music designated by the user is repeatedly played. The playback mode is selected by the user.

  An example of a procedure for transmitting music content from the server 2 to the client 3 will be described with reference to FIG. Transmission of music content starts with a user's playback instruction as a trigger. When the user operates the input unit 37, a playback mode selection screen is displayed on the display unit 38 of the client 3. On the playback mode selection screen, album playback, artist playback, playlist playback, and the like are displayed. When album playback is selected, a list of albums stored in the server 2 is displayed. When artist reproduction is selected, a list of artists stored in the server 2 is displayed.

  When one arbitrary album is selected from the album list, the server 2 transmits a reproduction list of the selected album to the client 3 (I). The reproduction list describes reproduction order information and song information. As shown in FIG. 3, the music information includes the name of the music content, the content type, the sampling frequency, the number of channels, the number of bits, the playback time of the music content, the URL of the music content, and the like. The playlist can be classified into an album list, a playlist, an artist list, and the like. The album list is a list of songs included in the album, the playlist is a list of songs designated by the user, and the artist list is a list of songs created by the same artist.

  When the reproduction list is received, the client 3 causes the display unit 38 to display a list of songs included in the album. When playback is started when an album is selected, the client 3 starts a “normal playback mode” in which the songs recorded in the album are sequentially played back. When the repeat mode is set after the album is selected, the “repeat mode” in which one album is reproduced repeatedly is started. When one song is selected from the album and the repeat mode is set, the “1 repeat mode” is started in which one song is repeatedly played.

  The content request unit 32 requests the music content from the server 2 and reproduces the music content provided from the server 2. The content request unit 32 requests music content in units of music. The order in which requests are made depends on the playback mode. In the “normal playback mode”, the client 3 requests the music content according to the playback order described in the playback list. In the case of the “repeat mode”, the music content is requested according to the reproduction order described in the reproduction list, and when the last music content is reproduced, the music content request is repeated from the first song in the reproduction list. In the “1 repeat mode”, the designated song is requested, and when the reproduction of this song is completed, the same song is requested again (II). The server 2 transmits the requested music content to the client 3 (III).

  The received music content is stored in the reception ring buffer 33. The reception ring buffer 33 is configured as shown in FIG. A write pointer and a read pointer are set in the reception ring buffer 33. FIG. 4A shows a state of the reading operation. Data is read at regular intervals, and when music content stored in the reception ring buffer 33 is read, the area becomes a writable area. FIG. 4B shows the state of the write operation. In the write operation, an area in which the write pointer can be written is moved. When the writable area decreases, reception is waited until the reading operation proceeds.

  The content request unit 32 outputs a next music content transmission request to the server 2 before the reproduction of a certain music content is completed. This is called prefetching of music content. As shown in FIG. 4C, the music content is prefetched, and the music content currently being reproduced and the music content to be reproduced next are recorded continuously and continuously in the reception ring buffer 33. As described above, by seamlessly recording the next music content before the reproduction of a certain music content is completed, the music content can be continuously reproduced. Such a music playback method is called seamless playback.

  Seamless playback is suitable for playing live albums. When a live album is played with seamless playback, the audio waveform is played continuously without being interrupted at the track break when the music content tracks transition from the first song to the second song, the second song to the third song, and so on. The

Seamless playback, the reception ring buffer 3 3 and the capacity of the music content 3 seconds, then about 3 seconds from the start of recording a song to be reproduced until the reproduction of the currently playing song, for reception A joint of music exists in the ring buffer 33.

  FIG. 5 shows the state of the seam when seamless playback is performed. As shown in FIG. 5A, the N-th song and the N + 1-th song described in the play list are continuously recorded in the reception ring buffer 33 of the music content “continuous playback mode”. If the Nth song is the last song, nothing is recorded after the Nth song.

  In the “repeat mode”, music contents are reproduced in the order of the reproduction list, and when the reproduction list is completely reproduced, the reproduction is repeated from the first song in the reproduction list. In the “repeat mode” reception ring buffer 33, as shown in FIG. 5B, the Nth song and the N + 1th song described in the reproduction list are recorded seamlessly. If the Nth song is the last song, the first music content is recorded after the Nth song. In the “one song repeat mode”, one song is repeatedly played. In the reception ring buffer 33 in the “single music repeat mode”, the head portion of the same music is recorded after the music being reproduced.

  The playback mode switching unit 39 performs processing for selecting the music content to be played next instead of the content requesting unit 32 when the playback mode is switched during the playback of the content. FIG. 6 is a flowchart for explaining the operation of the playback mode switching unit 39. When switching of the playback mode is instructed by the user during the playback of the music content, the playback mode switching unit 39, based on the remaining playback time of the currently played song and the amount stored in the reception ring buffer 33, It is determined whether or not the music content currently being reproduced is already recorded in the reception ring buffer 33. When the music content currently being played is recorded to the reception ring buffer 33 and the next music content is recorded after this music content (step S1; YES), the playback mode switching unit 39 stops receiving the music to be reproduced next (step S2). Then, the reproduction mode switching unit 39 reproduces the currently reproduced music content recorded in the reception ring buffer 33 to the end (step S3), and the next music content to be reproduced according to the designated reproduction mode. Select. The selection method will be described later (step S4). The playback mode switching unit 39 switches the playback mode setting to the setting designated by the user (step S5).

  The playback mode switching unit 39 requests the server 2 for the selected song. The music content providing unit 24 of the server 2 transmits the music content requested from the reproduction mode switching unit 39 to the client 3. The client 3 receives the music content from the server 2 (step S6), and stores the received music content in the reception ring buffer 33. The reception ring buffer 33 outputs the music content recorded in the reception ring buffer 33 to the converter 34 (step S8) when a certain amount of music content stored in the buffer is stored (step S7; YES). ). The music signal output to the converter 34 is reproduced by the speaker 36 via the amplifier 35. On the other hand, if a certain amount of music content is not accumulated in step S7 (step S7; NO), the process waits until a certain amount of music content is accumulated.

  In step S1, when the end of the currently reproduced song has not been received (step S1; NO), the reproduction mode switching unit 39 switches the reproduction mode according to the user's instruction (step S9). Then, the music to be reproduced next is selected based on the reproduction mode switching direction and the currently reproduced music (step S10). The music selection method is the same as the method described in FIG. The selection method will be described later.

  Then, while the reproduction of the music content currently being reproduced is continued, the reception of the currently reproduced song is continued until all the currently reproduced songs are received (step S11; NO). Then, when the reception of all the music currently being reproduced is completed (step S11; YES), the server 2 is requested for the music selected in step S10 (step S12).

  The reception ring buffer 33 outputs the music content stored in the reception ring buffer 33 to the converter 34 when a certain amount of music content stored in the buffer has been stored (step S13; YES) (step S8). ). The music signal output to the converter 34 is reproduced by the speaker 36 via the amplifier 35. On the other hand, if a certain amount of music content is not accumulated in step S12 (step S13: NO), the process waits until a certain amount of music content is accumulated.

  With reference to FIG. 7, a description will be given of the switching direction of the playback mode and a method of selecting music content according to the switching direction. The switching direction of the playback mode includes switching from “continuous playback mode” to “repeat mode”, switching from “repeat mode” to “continuous playback mode”, switching from “1 repeat mode” to “repeat mode”, There are six switching directions: switching from “repeat mode” to “1 repeat mode”, switching from “continuous playback mode” to “1 repeat mode”, and switching from “1 repeat mode” to “continuous playback mode”. .

  When the user instructs switching to “repeat mode” while playing music content in “continuous playback mode”, the playback mode switching unit 39 causes the currently played song to be the last song in the playlist. The server 2 is requested for the first song in the playlist. On the other hand, when the currently playing song is a song other than the last song in the playlist, the server 2 is requested for the next song in the playlist.

  When the user instructs to switch to the “continuous playback mode” while playing music content in “repeat mode”, the playback mode switching unit 39 indicates that the currently playing song is the last song in the playlist. After playing the current song to the end, stop playing. On the other hand, when the currently playing song is a song other than the last song in the playlist, the server 2 is requested for the next song in the playlist.

  When the user instructs to switch to “repeat mode” while playing music content in “1 repeat mode”, the playback mode switching unit 39 reads and reads the playback list including the currently playing song. The server 2 is requested for the next song in the playlist. Then, the playback mode is switched to “repeat mode”.

  When the user instructs to switch to “1 repeat mode” while playing music content in “repeat mode”, the playback mode switching unit 39 requests the server 2 for the currently played song. Then, the playback mode is switched to “1 repeat mode”. In the “1 repeat mode”, the same song as the currently playing song is repeatedly played.

  When the user instructs to switch to “1 repeat mode” while playing music content in “continuous playback mode”, the playback mode switching unit 39 requests the server 2 for the currently played music. Then, the playback mode is switched to “1 repeat mode”. In the “1 repeat mode”, the same song as the currently playing song is repeatedly played.

  When the user instructs to switch to “continuous playback mode” while playing music content in “1 repeat mode”, the playback mode switching unit 39 reads and plays back a playlist including the currently played song. The server 2 is requested for the next song in the list. If the currently playing song is the last song in the playlist, the playing is stopped after playing the currently playing song.

  The reception ring buffer 33 outputs a music content to the converter 34 and reproduces it after a certain amount of music content has been accumulated in order to realize stable reproduction. When there is a piece of music in the reception ring buffer 33, if switching of the playback mode is instructed, it takes time to receive the music content according to the switching of the playback mode. Depending on the timing, reading of the ring buffer for reception 33 may catch up with reception of new music content, and music may not be reproduced.

  In the content playback system 1 to which the present invention is applied, as shown in the flowchart of FIG. 6, after the start of receiving the next music content, when the switching of the playback mode is instructed, the reception of the already received music content is stopped. Then, when the reproduction of the currently reproduced music content is completed, the server 2 is requested to request the music content corresponding to the switching direction of the reproduction mode. As a result, the playback mode can be switched even during playback of music content.

It is a block diagram which shows the structure of a content reproduction system. It is a figure which shows an example of the procedure which transmits a music content from a server to a client. It is a figure which shows the structure of a play list. It is a figure which shows the mode of the reading in the ring buffer for reception, and writing. It is a figure which shows the state of the seam when seamless reproduction is performed. It is a flowchart which shows operation | movement of the reproduction | regeneration mode switching part. It is a figure which shows the selection method of the music content according to the switching direction of a reproduction mode at the time of reproduction mode switching, and a switching direction.

Explanation of symbols

1 content playback system, 2 server, 3 client, 4 switching hub, 21 content storage unit, 22 playback list storage unit, 23 communication unit, 24 music content providing unit, 31 communication unit, 32 content request unit, 33 reception ring buffer 34 Converter 35 Amplifier 36 Speaker 37 Input unit 38 Display unit 39 Playback mode switching unit

Claims (4)

A content storage device comprising content storage means for storing content whose playback order is predetermined by the playback order information;
Communication means for communicating with the content storage device;
Requesting means for determining a content to be reproduced next based on the reproduction order information and the type of reproduction mode, and requesting the content storage device to transmit the content;
Playback means for playing back the content;
Temporary storage means for temporarily storing the content received from the content storage device and outputting the stored content to the reproduction means at a predetermined speed;
Content comprising: playback mode switching means for selecting a content to be reproduced next instead of the request means when the reproduction mode is switched during the reproduction of the content, and making a transmission request for the content to the content storage device have a and reproducing apparatus,
The reproduction mode switching means is
If switching of the playback mode is instructed when the content being played back and the content to be played back next are stored in the temporary storage means, reception of the content to be played back next is stopped and the playback is performed. After the reproduction of the content in the middle is completed, the next content to be reproduced is selected based on the reproduction order information and the designated reproduction mode ,
When switching of the playback mode is instructed when only the content being played back is stored in the temporary storage means, the content to be played next based on the playback order information and the instructed playback mode A content reproduction system characterized by selecting .   The playback mode includes a continuous playback mode that plays back content in the order of the playback order information, a repeat mode that repeats playback of content in the order of the playback order information, and a repeat mode that repeats playback of a single content. The content reproduction system according to claim 1, wherein: A content playback apparatus that receives content whose playback order is determined in advance by playback order information and plays back the received content,
Requesting means for determining a content to be reproduced next on the basis of the reproduction order information and the reproduction mode and requesting transmission of the content;
Playback means for playing back the content;
Temporary storage means for temporarily storing the content received from the content storage device and outputting the stored content to the reproduction means at a predetermined speed;
When reproduction mode during reproduction of the content has been switched, to select the content to be reproduced next on behalf of the requesting means, e Bei and a reproduction mode switching means for performing a transmission request for the content,
The reproduction mode switching means is
If switching of the playback mode is instructed when the content being played back and the content to be played back next are stored in the temporary storage means, reception of the content to be played back next is stopped and the playback is performed. After the playback of the content within is completed, the content to be played next is determined based on the playback order information and the designated playback mode,
When switching of the playback mode is instructed when only the content being played back is stored in the temporary storage means, the content to be played next based on the playback order information and the instructed playback mode A content reproduction apparatus characterized by selecting . A content playback method of a content playback system comprising a content storage device that stores content whose playback order is predetermined by playback order information and a content playback device that plays back the content stored in the content storage device,
A playback order information transmitting step for transmitting the playback order information from the content storage device to the content playback device;
A playback mode setting step for setting a playback mode of the content playback device;
A selection step of selecting content to be reproduced next based on the reproduction order information and the set reproduction mode;
A content requesting step for requesting the content storage device to transmit the selected content;
A content storage step of storing the content transmitted from the content storage device in a temporary storage means;
A reproduction step of reproducing the content stored in the temporary storage means at a predetermined speed;
A reproduction mode switching step of selecting a content to be reproduced next when a reproduction mode is switched during reproduction of the content and performing a transmission request for the content to the content storage device ;
In the playback mode switching step,
If switching of the playback mode is instructed when the content being played back and the content to be played back next are stored in the content storage means, reception of the content to be played back next is stopped, and the playback is performed. After the playback of the content within is completed, the content to be played next is determined based on the playback order information and the designated playback mode,
When switching of the playback mode is instructed when only the content being played back is stored in the temporary storage means, the content to be played next based on the playback order information and the instructed playback mode A content reproduction method characterized by selecting .

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