KR20060064907A - Apparatus and method for generating time-shifted channel - Google Patents

Abstract

A time-shifted channel generator is disclosed. A stream receiving unit which receives streaming data information from a stream server; A ring buffer for storing streaming data information transmitted from the stream receiving unit; An RTSP server that receives a command transmitted through a set-top box from a user and delivers the command to a server manager and an RTP server; An RTP server extracting streaming data information corresponding to the requested time from the streaming data information stored in the ring buffer according to a command transmitted from the RTSP server, generating new streaming data, packetizing it, and transmitting the packet data to the set-top box; And a server manager for generating a thread for receiving the streaming data information from the stream receiving unit after reading the system configuration information and for generating an RTSP / RTP server thread to process the connection request from the RTSP server.

On Demand, SETTOPBOX, Time Shift, Multicast, Unicast

Description

Apparatus and Method for generating time-shifted channel

1 is a block diagram showing the configuration of a time-shifted channel generator according to an embodiment of the present invention.

2 is a conceptual diagram showing the structure of a ring buffer applied to the present invention.

3 is a flowchart for explaining a receiving process.

4 is a flowchart for explaining a transmission process.

The present invention relates to a time-shifted channel generating apparatus and a generating method.

With the introduction of FTTH (Fiber To The Home) networks, it is possible to provide high-quality broadcasting and communication convergence services, which leads to increasing demand for personalization of channels that broadcasters could not do.

As such, a set-top box equipped with a DVR (Digital Video Recorder) function has been proposed as an alternative for personalizing a channel for watching a desired program at a desired time.

However, set-top boxes have problems in many respects.

First of all, because the set-top box itself is expensive, only a limited number of people purchase it, which is an obstacle to activation. In the same vein, maintenance costs in case of failure of the storage device of the set-top box are high.

In the case of the set-top box, the tuner has 1-2 tuners and the temporary storage time is 10-30 minutes, so the time-shift function can be used only for the channel being watched or set. Moreover, if there are overlapping programs to record between channels due to the limit of the number of tuners, there is no solution.

In addition, since digital programs are stored in the storage device of the set-top box itself, digital copyrights are likely to be illegally used.

Accordingly, the present invention has been made to solve the above problems, and an object of the present invention is to provide a time-shifted channel generating apparatus for generating a time-shifted channel so that each individual can watch a desired program at a desired time. To provide.

Another object of the present invention is to provide a channel generating method applied to the time-shifted channel generating apparatus.

Other objects and features of the present invention will be clearly understood through the preferred embodiments described below.

In accordance with another aspect of the present invention, a time-shifted channel generating apparatus includes a stream receiving unit which receives streaming data information from a stream server; A ring buffer for storing streaming data information transmitted from the stream receiving unit; An RTSP server that receives a command transmitted through a set-top box from a user and delivers the command to a late server manager and an RTP server; An RTP server extracting streaming data information corresponding to the requested time from the streaming data information stored in the ring buffer according to a command transmitted from the RTSP server, generating new streaming data, packetizing it, and transmitting the packet data to the set-top box; And a server manager for generating a thread for receiving the streaming data information in the stream receiving unit after reading the system configuration information and for generating an RTSP / RTP server thread for processing the connection request from the RTSP server.

Preferably, the server manager analyzes the usage pattern of the user by referring to the reception state of the stream receiver and the command received by the RTSP server.

The ring buffer applied to the present invention includes a TS ring file buffer for storing a TS packet file and a PES packet file, a PES ring file buffer, a PES index ring buffer for storing TS packet file / PES packet file pointer information, and a PES index information. A GOP index ring buffer for storing sequence index information and a sequence index ring buffer for storing GOP index information.

The time-shifted channel generation method according to an aspect of the present invention is applied to a time-shifted channel generation apparatus having a ring buffer shared by a stream receiver and a stream transmitter, and receives TS packets transmitted from a stream server. step; Storing a TS packet file / PES packet file and index information generated based on the received TS packet in a ring buffer; Receiving a playback command from a user through a set-top box, extracting index information from a ring buffer, and extracting a TS packet from a TS packet file based on the extracted index information; And transmitting the extracted TS packet to the set top box.

The time-shifted channel generation method according to another aspect of the present invention is applied to a time-shifted channel generation apparatus having a ring buffer shared by a stream receiver and a stream transmitter, and receives TS packets transmitted from a stream server. step; Storing a TS packet file / PES packet file and index information generated based on the received TS packet in a ring buffer; Extracting index information from a ring buffer by receiving a move command from a user through a set-top box, and extracting a PES packet from a PES packet file based on the extracted index information; Encoding the extracted PES packet into a TS packet; Transmitting the encoded TS packet to the set-top box.

Preferably, the frame is reconstructed according to the moving speed only from the extracted PES information to the I-picture.

Preferably, checking whether the transmitted TS packet is the last TS packet for one PES, and extracting the next PES information from the ring buffer if it is the last TS packet; It is checked whether the PES packet for the transmitted TS packet is the last PES packet for one GOP, and in the case of the last PES packet, the next GOP information is extracted from the ring buffer.

Hereinafter, with reference to the accompanying drawings will be described an embodiment of the present invention.

1 is a block diagram showing the configuration of a time-shifted channel generator according to an embodiment of the present invention.

In the overall configuration, a streaming server 100 for transmitting streaming data and a time-shifted channel generator 200 for receiving streaming data from the streaming server 100 and generating a time-shifted channel and multicasting the customer It is composed of owned set-top box (300, 310, 320, 330).

In this embodiment, for convenience of description, it is assumed that streaming data is transmitted from the streaming server 100 to the time-shifted channel generator 200 through 21 channels.

According to the present invention, the time-shifted channel generator 200 includes a stream receiver 210, ring buffers 220 and 220a, RTSP / RTP servers 230 and 240, and a server manager 250. The information manager 260 is connected to the server manager 250, and the information database 260 stores various pieces of information such as member information, reserved set-top box information, or program usage pattern information.

The stream receiver 210 manages a state of a network interface for receiving streaming data transmitted from the streaming server 100, and a plurality of threads 211 and 212 for receiving streaming data by the server manager 250. And extract the transport stream (hereinafter referred to as TS) packet from the received streaming data to obtain related information.

The ring buffers 220 and 220a corresponding to the respective stream receivers 210 and 210a store TS packet related information received and transmitted by the stream receivers 210 and 210a.

Here, the TS packet related information includes TS packet file, PES (Packetized Elementary Stream) packet file, TS packet file / PES packet file pointer information, and index information including a sequence index, a group of picture (GOP) index, and a PES index. do.

Referring to FIG. 2, the structures of the ring buffers 220 and 220a are illustrated. The ring buffers 220 and 220a include an index ring buffer loaded in a memory and a ring file buffer stored in a file system.

The index ring buffer includes a PES index ring buffer 223 for storing TS packet file / PES packet file pointer information, a GOP index ring buffer 222 for storing PES index information and sequence index information, and a sequence index for storing GOP index information. Ring buffer 221.

In addition, the ring file buffer includes a TS ring file buffer 224 and a PES ring file buffer 225 for storing the TS packet file and the PES packet file, respectively.

In FIG. 2, vertical bars connected between the dots shown in each of the index ring buffer and the ring file buffer indicate positions according to corresponding index information or pointer information.

The size of each index ring buffer is variable according to the time-shifted time, and is set according to the number of PES, GOP and sequence of the input stream.

Referring to FIG. 1, the RTSP server 230 receives a play-related command, for example, a play, stop, rewind, fast forward, or jump command, from a user's set-top box and transmits it to the RTP server 240.

The RTP server 240 generates new streaming data by extracting streaming data corresponding to the requested time from the streaming data stored in the ring buffers 220 and 220a according to a play-related command transmitted from the RTSP server 230. To the set top box (300, 310, 320, 330).

After reading the system configuration information, the server manager 250 creates a thread for the stream receiver 210 to receive streaming data, and receives a connection request from the RTSP server 230 to process the RTSP / RTP server thread. (231, 232, 233, 234).

In addition, the server manager 250 may store the user's usage pattern in the information database 260 by referring to the reception state of the stream receiver and the playback related command received by the RTSP server 230.

A channel generation method by the time-shifted channel generator having such a configuration will be described.

3 is a flowchart for explaining a receiving process.

The server manager 250 creates a thread for reception in the stream receiver 210 to receive the TS packet transmitted through each channel from the streaming server 100.

Accordingly, the stream receiver 210 receives the TS packet from the stream server 100 through the corresponding channel (step S31).

It is determined whether the TS packet has completed one PES packet (step S32). If the PES packet has not yet been completed, the TS packet is stored in a temporary buffer (step S33).

When one PES packet is completed, the TS packet is stored in the TS ring file buffer 224 (step S34), and the completed PES packet is stored in the PES ring file buffer 225 (step S35).

Subsequently, start_code_prefix of the PES packet is checked to store start GOP information in the sequence index ring buffer 221 in response to the case of a sequence, a GOP or a picture, respectively (step S37), and the PES index information in the GOP index ring buffer 222. And sequence index information (step S38), and also store PES ring file buffer information and TS ring file buffer information in the PES index ring buffer 223 (step S39).

4 is a flowchart for explaining a transmission process.

It is determined whether a command is received from the set-top box while waiting for a connection from the set-top boxes 300, 310, 320, and 330 of the user (step S41).

For example, if the user wants to watch the previous contents of the program again while watching the program from the streaming server 100 in real time, the user selects, for example, a rewind function in the set-top box 300. do. The set top box 300 transmits a rewind command and current time information to the channel generator 200 according to a user's function selection. The server manager 250 of the channel generator 200 generates a transmission thread while receiving a command.

In this case, the transmitted time information may be used as a reference time in the process of performing the rewinding process.

 If it is determined that the rewind command has been received, the command state in the channel generating apparatus 200 is changed (step S42).

Subsequently, the RTSP server 230 of the channel generator 200 transmits the received command and current time information to the RTP server 240 through the generated transmission thread, and the RTP server 240 is illustrated in FIG. 2. The start GOP information corresponding to the current time information is extracted from the GOP index ring buffer 222 (step S43).

Further, starting PES information is extracted from the GOP index ring buffer 222 from the extracted starting GOP information (step S44).

Thereafter, the type of the received command is determined (step S45), and the process of steps S49 to S56 is performed because the received command is rewind.

That is, the frame is reconstructed using only the I-picture from the PES information according to the rewind speed (step S49), and the PES ring file buffer information is extracted from the PES index ring buffer 223 using the start PES information extracted in step S44 ( Step S50).

Subsequently, a PES packet is extracted from the PES ring file buffer 224 using the extracted PES ring file buffer information (step S51), and a TS packet is generated by encoding the extracted PES packet (step S52).

The RTP server 240 stream-transmits the generated TS packet to the set-top box 300 (step S48).

Then, it is checked whether the currently transmitted TS packet is the last TS packet for one PES (step S53). If it is not the final TS packet, the process proceeds to step S41. In the case of the last TS packet, the GOP index ring buffer 222 The next PES information is extracted (step S54).

In addition, it is checked whether the PES packet for the currently transmitted TS packet is the last PES packet for one GOP (step S55), and if it is not the final PES packet, the process proceeds to step S41. In the case of the last PES packet, the sequence index ring The next GOP information is extracted from the buffer 221 (step S56).

Although the process for the forward command is described here, the same applies to the fast forward command. However, in the steps S54 and S56, the term "next" means the previous time based on the current time information for the rewind command and the later time based on the current time information for the fast forward command. It should be noted that

The user may select a stop function in the set-top box 300 when the image that he / she wants to see is displayed while viewing the search image displayed on the display through the set-top box 300.

Accordingly, the process of steps S41 to S44 described above is performed, and the process returns to step S41 without any further progress since the type of command is stopped in step S45.

Then, when the user selects the playback function in the set-top box 300, the processes of steps S41 to S44 are similarly performed, and the processes of steps S46 to S56 are performed since the type of command is reproduced in step S45.

More specifically, the TS ring file buffer information is extracted from the PES index ring buffer 223 using the start PES information extracted in step S44 (step S46), and the TS ring file buffer is referenced with the extracted TS ring file buffer information. The TS packet is extracted from step 225 (step S47), and the TS packet stream is transmitted to the set-top box 300 of the user (step S48).

It is checked whether the currently transmitted TS packet is the last TS packet for one PES (step S53). If it is not the last TS packet, the process proceeds to step S41. In the case of the last TS packet, the GOP index ring buffer 222 next checks. PES information is extracted (step S54).

In addition, it is checked whether the PES packet for the currently transmitted TS packet is the last PES packet for one GOP (step S55), and if it is not the final PES packet, the process proceeds to step S41. In the case of the last PES packet, the sequence index ring The next GOP information is extracted from the buffer 221 (step S56).

Unless another command is transmitted from the set-top box 300, the playback process consisting of steps S41, S45, S46 to S56 is repeatedly performed, and the user can continue to watch the previous program based on the current time.

Although the above has been described with reference to the preferred embodiments of the present invention, various changes and modifications can be made without departing from the spirit of the present invention.

For example, when a command is transmitted from the set-top box, the channel generator does not request the current time information from the set-top box, but receives the final time to jump when fast forwarding or rewinding. PES information can be extracted.

Therefore, the scope of the present invention should not be limited to the above embodiments, but should be determined by the claims described below.

 According to the present invention, there is no need to implement the PVR function in the set-top box itself owned by the individual can be purchased at a low cost, there is an advantage that does not cost maintenance.

In addition, compared to the case of the set-top box, it is always available without any special setting within a preset time range for all receivable channels.

In particular, since there are no restrictions on the number of tuners and storage space, there is no problem because data is stored in a ring buffer for each channel even when programs to be recorded are overlapped.

In addition, in a set-top box, since digital programs are stored illegally in a storage device thereof, digital copyright is likely to be illegally used. However, in the case of the present invention, since the channel creator autonomously has a storage space, there is no such risk.

Claims (7)

A stream receiving unit which receives streaming data information from a stream server; A ring buffer for storing streaming data information transmitted from the stream receiving unit; An RTSP server that receives a command transmitted through a set-top box from a user and delivers the command to a late server manager and an RTP server; An RTP server extracting streaming data information corresponding to the requested time from the streaming data information stored in the ring buffer according to a command transmitted from the RTSP server, generating new streaming data, packetizing it, and transmitting the packet data to the set-top box; And And a server manager for generating a thread for receiving the streaming data information in the stream receiving unit after reading the system configuration information and for generating an RTSP / RTP server thread for processing the connection request from the RTSP server. And a time-shifted channel generator. The apparatus of claim 1, wherein the server manager analyzes a user's usage pattern by referring to a reception state of the stream receiver and a command received by the RTSP server. The PES index ring buffer and PES index of claim 1, wherein the ring buffer stores a TS ring file buffer, a PES ring file buffer, and a TS packet file / PES packet file pointer information for storing TS packet files and PES packet files, respectively. And a GOP index ring buffer for storing information and sequence index information and a sequence index ring buffer for storing GOP index information. A ring buffer shared by the stream receiver and the stream transmitter, Receiving a TS packet transmitted from a stream server; Storing the TS packet file / PES packet file and index information generated based on the received TS packet in the ring buffer; Receiving a playback command from a user through a set-top box, extracting index information from the ring buffer, and extracting a TS packet from the TS packet file based on the extracted index information; And And transmitting the extracted TS packet to the set top box. A ring buffer shared by the stream receiver and the stream transmitter, Receiving a TS packet transmitted from a stream server; Storing the TS packet file / PES packet file and index information generated based on the received TS packet in the ring buffer; Extracting index information from the ring buffer by receiving a move command from a user through a set-top box, and extracting a PES packet from the PES packet file based on the extracted index information; Encoding the extracted PES packet into a TS packet; And transmitting the encoded TS packet to the set top box. 6. The method of claim 5, further comprising reconstructing a frame according to the moving speed from the extracted PES information to an I-picture only. 6. The method of claim 4 or 5, further comprising: checking whether the transmitted TS packet is the last TS packet for one PES, and extracting next PES information from the ring buffer if the TS packet is the last TS packet; Checking whether the PES packet for the transmitted TS packet is the last PES packet for one GOP, and extracting the next GOP information from the ring buffer if the PES packet is the last PES packet.

Images