JP2009141841A - Data stream transmission method, transmitting side device, and receiving side device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently transmit a data stream, while preserving the time intervals of valid packets without requiring an advanced circuit in a time stamp processing. <P>SOLUTION: A packet group comprising a plurality of valid packets and invalid packets composing the data stream is stored in a frame having a fixed bit length along its time series, and a time stamp is given to the frame as a whole. At this time, the packet group is prepared so that the packets at its top and at its tail become the valid packets, and the invalid packets existing between the valid packet acting as the tail of the frame and the valid packet acting as the top of the next frame are eliminated. At this time, information regarding the number of the invalid packets eliminated is given as the time stamp. On the receiving side, among a number of invalid packets that have been recognized based on the time stamp are inserted between adjacent packet groups extracted from the frame to restore the time intervals on the transmitting side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention is used for transmission of a data stream configured by mixing valid packets and invalid packets.

  When a digital video signal or audio signal is transmitted / received via a transmission path, the MPEG (Moving Picture Experts Group) method (MPEG-1: ISO / IEC11172, which compresses original digital data in order to reduce transmission capacity) MPEG-2: ISO / IEC 13818) and H.264. The H.264 / AVC system (ISO / IEC 14496-10) has been put into practical use.

TS (Transport) is used as a packet to deliver these compressed video or audio digital data.
Stream) packet, and DVB-ASI (Digital Video) is used as a physical interface standard for transmitting the TS packet.
There is a Broadcasting-Asynchronous Serial Interface) method (EN50084-9). In the following description, the TS packet is referred to as a valid packet.

  The effective packet has a fixed byte length of 188 bytes. In the broadcasting system, a 204-byte length obtained by adding 16 bytes to the Reed-Solomon error correction code is used as the TS packet in the broadcasting system. Therefore, in this specification, in order to correspond to the two packet lengths, the effective packet length is hereinafter expressed in a format of 188 (204) bytes (no error correction code (with error correction code)).

  FIG. 7 schematically shows the DVB-ASI system. As shown in FIG. 7, the DVB-ASI system transmits TS packets that are valid packets at a constant transmission rate of 270 Mbps. That is, when the TS rate is low and there is no valid packet to be transmitted, an invalid packet is inserted to keep the transmission rate constant at 270 Mbps.

In the DVB-ASI system, this invalid packet consists of 10 bits and is defined as K28.5 words. Further, it is standardized that at least two invalid packets must be inserted between valid packets. Furthermore, in the DVB-ASI system, the data stream is transmitted after being converted to 8B / 10B, so that a TS packet having a length of 188 (204) bytes is 188 (204) × 8 × (10/8) = 1880 (2040).
Therefore, it is converted into 1880 (2040) bits and transmitted.

Therefore, the maximum transmission rate of valid packets that can be transmitted using the DVB-ASI method is when two invalid packets are inserted between valid packets.
(270 × (8/10) × 1880 (2040)) / (1880 (2040) + 10 × 2)) ≈213.72 (213.90)
Therefore, it is about 214 Mbps.

  On the other hand, in MPEG-2 Systems (ISO / IEC13818-1) used in digital broadcasting and the like, in order to synchronize the clock between the reception side and the transmission side, PCR (Program Clock Reference) which is reference time information is used as timing information. ) Is written in a valid packet and must be transmitted periodically. At this time, in order to ensure that the clock on the receiving side operates stably, the PCR transmission interval is set to a constant value of 100 msec or less.

  In the current radio frequency (RF) radio wave broadcasting, the broadcast signal capacity that can be distributed by each broadcasting station is limited by the limitation of the radio wave broadcasting band. For example, in the case of terrestrial digital broadcasting, the maximum transmission rate is 23.23 Mbps per broadcasting station, and 52.17 Mbps in BS digital broadcasting. For this reason, the transmission rate of the compressed video / audio signal using MPEG-2 in radio broadcasting is much smaller than the transmission rate 270 Mbps defined in the DVB-ASI system.

  Therefore, in the DVB-ASI system, even when the effective transmission rate of valid packets is small, the data stream must be transmitted with the output speed kept constant as described above, and therefore the invalid stream K28.5 occupies most of the data stream. Will be. Therefore, the transmission efficiency is in a bad state.

  On the other hand, in the case where valid packets are rearranged and transmitted in a frame on an asynchronous network such as Ethernet (registered trademark), for example, in consideration of deleting invalid packets to increase transmission efficiency, PCR is performed. This causes a problem that the processing timing of valid packets cannot be restored on the receiving side.

  FIG. 8 schematically shows a conventional time stamping method. Therefore, in order to solve this problem, as shown in FIG. 8 until now, invalid packets between all valid packets are deleted, and time information between valid packets is added to valid packets as time stamps to transmit frames. A method (TTS method: Time stamped TS method) has been proposed.

  As a method of adding time stamp information, there are a method of calculating and adding the number of deleted invalid packets, a method of calculating the time between effective packets using an internal clock (for example, calculating the number of rising times), and the like. Proposed. In the latter, 4 bytes are defined as the time stamp, and the format given to the head of the valid packet is standardized (for example, refer to Patent Document 1 for the former and Non-Patent Document 1 for the latter).

JP 2001-308876 A ARIB STD-B24 version 3.4, “Data Broadcast Coding and Transmission Methods for Digital Broadcasting”, The Japan Radio Industry Association, July 25, 2002

  As described above, regarding the current radio broadcast, the maximum transmission rate is limited due to the limitation of the radio broadcast band. However, for example, in the case where effective packets are rearranged and transmitted in a transmission frame on an asynchronous network in FTTH (Fiber To The Home) broadcasting using an optical fiber, the total transmission capacity is 10 Gbps or more than radio broadcast capacity. Is possible. For this reason, the band limitation allocated to each broadcasting station is relaxed, and it becomes possible to distribute a broadcast signal that uses the DVB-ASI transmission rate of 270 Mbps to the maximum extent.

  As described above, the DVB-ASI method stipulates that at least two (20 bits) invalid packets are inserted between valid packets. Therefore, since the conventional time stamping method as described above uses 4 bytes (32 bits) for the time stamp, when the effective rate of the effective packets is very high (the ratio of the effective packets to the data stream is large), The transmission efficiency is worse than that of the DVB-ASI system.

  In addition, since the time stamping process is performed for each valid packet, if the effective rate of the valid packet is high, the processing load associated with time stamping and removal increases, and high-performance hardware is required. .

  The present invention has been made in order to solve such a problem. For a data stream having a very high effective packet effective rate, an advanced circuit is not required in time stamp processing, and the effective packet It is an object of the present invention to provide a data stream transmission method, a transmission side apparatus, and a reception side apparatus that can efficiently transmit a data stream while preserving a time interval.

  The present invention relates to a plurality of valid packets and invalid data constituting a data stream in a transmission side device that transmits a data stream composed of a mixture of valid packets loaded with data and invalid packets loaded with no data. When a packet group consisting of packets is stored in a fixed-length frame so that the leading and trailing packets are valid packets along the time series, the valid packet that is the end of the frame and the valid that is the beginning of the next frame Packet group creation means for deleting invalid packets existing between packets, and time stamp giving means for giving packet number information of deleted invalid packets as a time stamp to the entire frame It is characterized by that.

  According to this, for packets stored in a fixed-length frame, valid and invalid packets transmitted from the data transmission source are stored in chronological order as they are, and time interval information is preserved. Therefore, it is not necessary to add a time stamp, and time stamp processing can be omitted.

  Also, the packet group is created so that the leading and trailing packets are valid packets, and the invalid packet existing between the valid packet at the end of the frame and the valid packet at the beginning of the next frame is this. By deleting, it becomes unnecessary to insert invalid information between adjacent frames, and transmission efficiency can be improved.

  In this case, however, the time corresponding to the number of deleted invalid packets is shortened, so that accurate time interval information of packets constituting the data stream cannot be restored on the receiving side. In order to avoid such a problem, the time stamp assigning means assigns the packet number information of the invalid packets deleted by the packet group creating means as a time stamp.

  According to this, by referring to the time stamp on the reception side, the invalid packet deleted on the transmission side can be inserted again between valid packets, and the accurate time interval information of the packet can be restored.

  That is, when the present invention is viewed from the viewpoint of a receiving side apparatus, the present invention is a receiving side apparatus that receives the frame transmitted by the transmitting side apparatus of the present invention, and includes a group of packets stored in the frame. Data stream restoring means for extracting the data and restoring it to the original data stream, and the data stream restoring means invalidates the number of packets recognized based on the time stamp between adjacent packet groups extracted from the frame. A means for inserting a packet is provided.

  Further, when the present invention is viewed from the viewpoint of a data stream transmission method, the present invention transmits a data stream composed of a mixture of valid packets loaded with data and invalid packets loaded with no data. In the data stream transmission method executed by the transmission side device, the packet group creating means converts a packet group composed of a plurality of valid packets and invalid packets constituting the data stream, and the leading and trailing packets along the time series. When storing in a fixed-length frame so that it becomes a valid packet, the invalid packet existing between the valid packet at the end of the frame and the valid packet at the beginning of the next frame is deleted, and time stamp giving means The packet count information of deleted invalid packets for the entire frame. Characterized by applying as a timestamp Te.

  Furthermore, the present invention is a data stream transmission method executed by a receiving side device that receives the frame transmitted by the transmitting side device in the data stream transmission method of the present invention, wherein the data stream restoring means includes the frame When the packet group stored in is extracted and restored to the original data stream, invalid packets having the number of packets recognized based on the time stamp are inserted between adjacent packet groups extracted from the frame. It is characterized by that.

  Further, when viewed from the viewpoint of a program, the present invention is a program that, when installed in an information processing apparatus, causes the information processing apparatus to realize a function corresponding to the function of the transmission side apparatus of the present invention. .

  Alternatively, the present invention is a program that, when installed in an information processing apparatus, causes the information processing apparatus to realize a function corresponding to the function of the receiving-side apparatus of the present invention.

  According to the present invention, it is possible to efficiently transmit a data stream while preserving the time interval of effective packets without requiring an advanced circuit in the time stamp processing for a data stream having a very high effective packet effective rate. it can.

  An embodiment of the present invention will be described with reference to FIGS. FIG. 1 is a diagram showing a configuration of a time stamping unit 1 and a framing unit 2 which are transmission side devices according to the embodiment of the present invention. FIG. 2 is a diagram illustrating the configuration of the deframing unit 7 and the data stream restoration unit 8 which are reception side devices according to the embodiment of the present invention.

  As shown in FIG. 1, the embodiment of the present invention is a time which is a transmission side device that transmits a data stream composed of a mixture of valid packets loaded with data and invalid packets loaded with no data. In the stamping unit 1, a packet group consisting of a plurality of valid packets and invalid packets constituting a data stream is converted into a fixed length so that the framing unit 2 has its leading and trailing packets as valid packets along its time series. A packet group creation unit 3 that deletes an invalid packet existing between a valid packet at the end of the frame and a valid packet at the beginning of the next frame when stored in the frame, and the deleted invalid packet A time stamp giving unit 6 for giving the packet number information to the entire frame as a time stamp; That.

  The packet group creation unit 3 and the separation unit 4 create a packet group so that the leading and trailing packets are valid packets, and when the created packet group is stored in a fixed-length frame, Delete the invalid packet that exists between the valid packet that becomes and the valid packet that is the head of the next frame.

  That is, the packet group creation unit 3 creates a packet group having a valid packet at the beginning. At this time, if an invalid packet exists at the end, the separation unit 4 separates the invalid packet from the packet group and invalidates it. The data is transmitted to the packet counter unit 5. The time stamp assigning unit 6 assigns the number of invalid packets deleted by the separating unit 4 as a time stamp to the entire fixed-length frame in which the packet group is stored.

  In addition, as shown in FIG. 2, the data stream restoration unit 8 that is a receiving side device that receives a frame transmitted by the transmitting side device shown in FIG. 1 extracts a packet group stored in the frame and extracts the original packet group. A time stamp removing unit 9, an inserting unit 10, and an invalid packet counter unit 11 which are data stream restoring means for restoring to the data stream of the data stream, and this data stream restoring means is arranged between adjacent packets extracted from the frame. The number of invalid packets recognized based on the time stamp is inserted.

(Description of overview)
An outline of an embodiment of the present invention will be described with reference to FIGS. 3 and 4. FIG. 3 is a diagram schematically showing the time stamp assigning method according to the embodiment of the present invention. FIG. 4 is a diagram showing the relationship between the TS rate and the transmission efficiency in the conventional time stamping method and the time stamping method of the present invention.

  In the conventional method, a time stamp is assigned to each valid packet (for example, TS packet). However, in the method of the present invention, a fixed-length frame is prepared as shown in FIG. 3, and a plurality of valid packets are included in this frame. And invalid packets are stored along the time series, and a time stamp is given to the stored packet group.

  In the embodiment of the present invention, a valid packet is stored at the beginning, thereafter, a plurality of invalid packets and valid packets are stored, and a packet group that is a valid packet at the end is stored in a fixed-length frame. In other words, invalid packets are deleted only between a packet group stored in a certain frame and a packet group stored in the next frame, and the number of invalid packets is given to the head of the next packet group as a time stamp.

  FIG. 4 shows a case where one time stamp is given to a packet group (number of valid packets: n, number of invalid packets: n−1) composed of a plurality of valid packets and invalid packets (notation is defined as TTS / nTS). Transmission efficiency). Here, the transmission efficiency is defined as “number of bits of valid packet / number of bits of data stream” in the data stream.

  Further, the maximum TS rate in FIG. 4 indicates the maximum transmission rate (about 214 Mbps) of valid packets that can be transmitted using the DVB-ASI method described above. When the TS rate exceeds 210 Mbps, the method in which one time stamp is assigned to a plurality of valid packets and invalid packets has a higher transmission efficiency than the conventional method in which a time stamp is assigned to each valid packet. high. In addition, since the time stamping process is reduced to 1 / n, the circuit processing load is reduced.

  Therefore, for example, when retransmitting effective packets in a transmission frame on an asynchronous network in FTTH broadcasting, a data stream with an extremely high effective packet effective rate is compared with the conventional time stamping method. It can be expected to increase the transmission efficiency and reduce the processing load in the circuit.

(Detailed description of the embodiment 1)
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  A time stamping unit 1 and a framing unit 2 in the embodiment of the present invention are shown in FIG. Here, a MAC frame having a fixed length (1522 bytes, payload 1500 bytes) is used as a frame.

  The time stamping unit 1 is composed of a plurality of valid packets and invalid packets, and has a function of creating a packet group in which the first packet is a valid packet and the last packet is an invalid packet. A packet group creation unit 3 having the characteristics of 1496 bytes (1500-4 (time stamp)) or less when deleted, and a function of separating the last invalid packet group from the packet group sent from the packet group creation unit 3 The number of invalid packets calculated for the invalid packet group separated by the separation unit 4 and the invalid packet counter unit 5 having a function of expressing 4 bytes as time stamp information; The invalid packet counter unit 5 sends out the head of a packet group composed of valid packets and invalid packets. Consisting of a time stamp giving section 6 for imparting a time stamp information.

  The time-stamped packet group is stored in the payload portion of a fixed-length (1522 bytes) MAC frame in the framing unit 2 and transmitted.

  Next, the time stamp assigning unit 6 will be described with reference to FIGS. FIG. 5 is a diagram showing a configuration of the time stamping unit 1 according to the embodiment of the present invention. FIG. 6 is a flowchart showing a processing procedure of the time stamping unit 1 according to the embodiment of the present invention.

  Here, J is defined as a function representing the number of valid packets, and L is defined as a function for determining whether or not a certain threshold (1308 (1292 bytes) in the present invention) is exceeded with respect to the memory amount stored in the FIFO 32. To do. The initial values of both J and L are “0” (steps S1 and S2).

  First, the packet discriminating unit 31 discriminates whether a packet is a valid packet or an invalid packet for a data stream transmitted from the transmission source using the DVB-ASI method (step S3). Using the 8-byte synchronization signal defined at the head of the valid packet, it is recognized as a valid packet when the bit pattern is 0 × 47 (Yes in step S3). On the other hand, the invalid packet is defined by K28.5 words, and is recognized as an invalid packet when this bit pattern is 00111111010 (invertible) (No in step S3).

  When the packet discriminating unit 31 discriminates a valid packet (Yes in step S3), a control signal is transmitted from the packet discriminating unit 31 to the valid packet counter unit 30, and the valid packet counter unit 30 increases the number of valid packets J by 1 ( Step S5).

  Valid packets and invalid packets are stored in the FIFO 32 (step S6). If the accumulated amount exceeds 1308 (1292) bytes (Yes in step S7), the valid packet or invalid packet is transmitted to the FIFO 32. The effective packet counter unit 30 is notified every time. The valid packet counter unit 30 receives this notification and increments L by 1 (step S8).

  Here, 1308 (1292) bytes is a numerical value obtained by subtracting 4 bytes of the time stamp and 188 (204) bytes of the valid packet from the 1500 bytes of the payload of the MAC frame. The byte length of the packet group of the valid packet and the invalid packet is this If the number is exceeded, it means that if a valid packet is further added to this packet group, the byte length of the packet group after the time stamp is added becomes longer than 1500 bytes and cannot be stored in the MAC frame.

  That is, when the valid packet counter unit 30 receives a control signal for recognizing a valid packet from the packet discrimination unit 31 in a state where the L value is other than “0” (No in step S4), the valid packet is stored in the FIFO 32. As a result, the packet group in the FIFO 32 cannot be stored in the MAC packet as described above. Therefore, before the valid packet is accumulated, the FIFO 32 sends a packet group of a plurality of valid packets and invalid packets accumulated to the separation unit 4 (step S9).

  At the same time, the valid packet counter unit 30 sends information on the counted number of valid packets J to the separation unit 4. In the packet group sent to the separation unit 4 using the above method, the valid packet + invalid packet group is repeated J times, and the bit length is within 1496 bytes if the invalid packet group at the end of this packet group is deleted. It has the following characteristics.

  In the separation unit 4, with respect to the packet group transmitted from the FIFO 32, the time stamp giving unit 6 from the head of the packet group to the Jth valid packet is obtained based on the information on the number of valid packets J obtained from the valid packet counter unit 30. And send the remaining invalid packet group to the invalid packet counter unit 5 which counts the number of invalid packets. The invalid packet counter unit 5 calculates the number of invalid packets sent from the separation unit 4 and accumulates a 4-byte time stamp value.

  That is, in the separation unit 4, if the value of the number of valid packets J from the valid packet counter unit 30 is not “0” (Yes in step S10), and the packet transmitted from the FIFO 32 is a valid packet (Yes in step S11). ), 1 is subtracted from the value of the number of valid packets J (step S12). In this way, when the value of the number of valid packets J from the valid packet counter unit 30 becomes “0” (No in step S10), the separation unit 4 determines the time from the beginning of the packet group to the Jth valid packet. The data is sent to the stamp attaching unit 6, and the remaining invalid packet group is sent to the invalid packet counter unit 5.

  The time stamp giving unit 6 gives a 4-byte time stamp corresponding to the number of invalid packets counted by the invalid packet counter unit 5 in the previous packet group to the head of the packet group sent from the separation unit 4. (Step S13). Further, the invalid packet counter unit 5 extracts the number of invalid packets sent from the separation unit 4 (step S14), and assigns a time stamp to prepare the time stamp for giving the number of invalid packets to the next packet group. The data is sent to the unit 6 (step S15).

  With the above processing, the time stamp assigning unit 6 is composed of a plurality of valid packets and invalid packets, and a packet group characterized in that the leading and trailing packets are valid packets. It is possible to send to the framing unit 2 a bit string having a total bit length of 1500 bytes or less of the payload length of the MAC frame.

  Further, when the effective rate of valid packets is very high in the DVB-ASI method, the invalid packet counter unit 5 and the time stamp assigning unit 6 may perform one process for J valid packets. The processing load is reduced as compared with a method of assigning one time stamp to one valid packet.

  The framing unit 2 stores in the payload portion of the MAC frame a packet group composed of valid packets and invalid packets to which the received time stamps are attached. When storing, null information is written in the remaining part of the payload, and the MAC frame is transmitted with a fixed length (1522 bytes).

  Next, a method for restoring the original broadcast station signal from the transmitted MAC frame will be described with reference to FIG. First, the deframing unit 7 receives the MAC frame and extracts the payload portion in the MAC frame. At this time, null information in the payload given by the framing unit 2 in FIG. 1 is deleted. The data stream restoration unit 8 has a feature of restoring the transmission source data stream from the packet group deframed based on the time stamp.

  The time stamp removing unit 9 extracts the time stamp defined by the first 4 bytes from the packet group composed of the time-stamped valid packet and invalid packet sent from the deframe unit 7, The information is sent to the invalid packet counter unit 11 and the packet group from which the time stamp has been removed is sent to the insertion unit 10. The invalid packet counter unit 11 creates an invalid packet K28.5 based on the time stamp information, and the insertion unit 10 transmits the invalid packet from the time stamp removing unit 9 and includes a valid packet and an invalid packet. Insert in front of the group.

  Through the above processing, it is possible to restore time interval information between valid packets.

(Detailed description of the embodiment 2)
By installing the information processing apparatus, the information processing apparatus realizes functions corresponding to the functions of the time stamping unit 1 that is the transmission side device and the data stream restoration unit 8 that is the reception side device of the above-described embodiment. An embodiment of the program will be described.

  By recording the program of the present embodiment on a recording medium, the information processing apparatus can install the program of the present embodiment using the recording medium. Alternatively, the program of this embodiment can be directly installed in the information processing apparatus via a network from a server that holds the program of this embodiment.

  Thereby, using the information processing apparatus, the time in the packet group creation unit 3, the separation unit 4, the invalid packet counter unit 5, the time stamp assignment unit 6, and the data stream restoration unit 8 in the time stamping unit 1 of the above-described embodiment. Functions corresponding to the functions of the stamp removing unit 9, the inserting unit 10, and the invalid packet counter unit 11 can be realized. Furthermore, functions corresponding to the functions of the framing unit 2 and the deframing unit 7 may be realized by the program of this embodiment.

  The program according to the present embodiment includes not only a program that can be directly executed by the information processing apparatus but also a program that can be executed by being installed on a hard disk or the like. Also included are those that are compressed or encrypted.

  According to the present invention, a data stream with an extremely high TS packet effective rate, such as FTTH, does not require an advanced circuit in time stamp processing, and data can be efficiently stored while preserving the time interval of TS packets. Streams can be transmitted.

It is a figure which shows the structure of the time stamp conversion part and framing part which are the transmission side apparatuses of embodiment of this invention. It is a figure which shows the structure of the deframing part and the data stream decompression | restoration part which are the receiving side apparatuses of embodiment of this invention. It is the figure which represented typically about the time stamp provision system of embodiment of this invention. It is the figure which showed the relationship between TS rate and transmission efficiency in the conventional time stamp provision system and the time stamp provision system of this invention. It is a figure which shows the structure of the time stamp conversion part of embodiment of this invention. It is a flowchart which shows the process sequence of the time stamp conversion part of embodiment of this invention. It is the figure which represented DVB-ASI system typically. It is the figure which represented typically about the conventional time stamp provision system.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Timestamping part 2 Framing part 3 Packet group preparation part 4 Separation part 5, 11 Invalid packet counter part 6 Time stamp provision part 7 Deframing part 8 Data stream decompression part 9 Time stamp removal part 10 Insertion part 30 Valid packet Counter unit 31 Packet discrimination unit 32 FIFO

Claims (6)

In a transmission side device that transmits a data stream composed of a mixture of valid packets loaded with data and invalid packets loaded with no data,
When a packet group consisting of a plurality of valid packets and invalid packets constituting a data stream is stored in a fixed-length frame so that the leading and trailing packets are valid packets along the time series, the end of the frame is A packet group creating means for deleting the invalid packet existing between the valid packet and the valid packet at the beginning of the next frame;
A transmission-side apparatus, comprising: a time stamp attaching unit that attaches the number of deleted invalid packet information as a time stamp to the entire frame. A receiving-side device that receives the frame transmitted by the transmitting-side device according to claim 1,
A data stream restoring means for extracting a packet group stored in the frame and restoring it to the original data stream;
The data stream restoring means comprises means for inserting invalid packets having the number of packets recognized based on the time stamp between adjacent packet groups extracted from the frame. In a data stream transmission method executed by a transmission-side device that transmits a data stream configured by mixing valid packets loaded with data and invalid packets not loaded with data,
When the packet group creation means stores a packet group consisting of multiple valid packets and invalid packets that make up the data stream in a fixed-length frame so that the first and last packets are valid packets along the time series. In addition, the invalid packet existing between the valid packet at the end of the frame and the valid packet at the beginning of the next frame is deleted,
A data stream transmission method, wherein the time stamp assigning means assigns, as a time stamp, packet number information of deleted invalid packets to the entire frame. The data stream transmission method according to claim 3, wherein the data stream transmission method is executed by a reception side device that receives the frame transmitted by the transmission side device.
When the data stream restoration unit extracts the packet group stored in the frame and restores the original data stream, the data stream restoration unit is recognized based on the time stamp between adjacent packet groups extracted from the frame. A data stream transmission method comprising inserting invalid packets of the number of packets.   The program which makes the information processing apparatus implement | achieve the function corresponding to the function of the transmission side apparatus of Claim 1 by installing in an information processing apparatus.   A program that, when installed in an information processing apparatus, causes the information processing apparatus to realize a function corresponding to the function of the receiving side apparatus according to claim 2.

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