Broadcast transport stream distribution system, and broadcast transport stream distribution apparatus, user terminal device and distribution method for use in the system

Abstract

In a transport stream distribution system, a transmission rate control unit takes in an IP packet output from an IP transmission processing unit, obtains a TTS to be added to an arbitrary TS packet in the IP packet, and compares the TTS with a time stamp generated internally to determine whether both of them coincide with each other or not. And if they coincide with each other, the system takes in a TTS of the next TS packet, and otherwise, the system obtains a difference between a time indicating the TTS and the time indicating the internally generated time stamp to calculate a transmission rate correction value equivalent to the value of the difference, and issues the calculated correction value to the processing unit to correct a transmission rate.

1 - 13 . (canceled) 
     
     
         14 . A broadcast transport stream distribution system, comprising:
 a distribution apparatus which distributes broadcast transport streams in which transport streams of broadcast program contents are packetized via a communication line through an Internet Protocol network; and   a user terminal device which receives the broadcast transport streams distributed from the distribution apparatus via the communication line; wherein   the distribution apparatus includes:
 a transmission unit which converts transport stream packets having time information of the broadcast transport streams into Internet Protocol packets and transmits the Internet Protocol packets; and 
 a control unit which extracts the time information of the transport stream packets from the Internet Protocol packets transmitted by the transmission unit, detects fluctuations in a transmission rate of the Internet Protocol packets based on the time information, and controls the transmission rate of the Internet Protocol packets based on a fluctuation detection result; and 
   the user terminal device includes:
 a buffer which temporarily stores the Internet Protocol packets transmitted via the communication line; and 
 a conversion unit that retrieves the Internet Protocol packets sequentially from the buffer and converts the Internet Protocol packets into the transport stream packets. 
   
     
     
         15 . The system according to  claim 14 , wherein
 the transmission unit removes NULL packets from the transport stream packets and converts the transport stream packets into the Internet Protocol packets.   
     
     
         16 . A broadcast transport stream distribution apparatus which distributes broadcast transport streams, in which transport streams of broadcast program contents are packetized, to a user terminal device via a communication line through an Internet Protocol network, the apparatus comprising:
 a transmission unit which converts transport stream packets having time information of the broadcast transport streams into Internet Protocol packets and transmits the Internet Protocol packets; and   a control unit which extracts the time information of the transport stream packets from the Internet Protocol packets transmitted by the transmission unit, detects fluctuations in a transmission rate of the Internet Protocol packets based on the time information, and controls the transmission rate of the Internet Protocol packets based on a fluctuation detection result.   
     
     
         17 . The apparatus according to  claim 16 , wherein
 the transmission unit removes NULL packets from the transport stream packets and converts the transport stream packets into the Internet Protocol packets.   
     
     
         18 . A user terminal device for use in a broadcast transport stream distribution system which distributes broadcast transport streams in which transport streams of broadcast program contents are packetized from a distribution apparatus via a communication line through an Internet Protocol network:
 wherein the distribution apparatus converts transport stream packets having time information of the broadcast transport streams into Internet Protocol packets and transmits the Internet Protocol packets, while extracting the time information of the transport stream packets from the Internet Protocol packets, detecting fluctuations in a transmission rate of the Internet Protocol packets based on the time information, and controlling the transmission rate of the Internet Protocol packets based on a fluctuation detection result;   the user terminal device comprising:
 a buffer which temporarily stores the Internet Protocol packets transmitted via the communication line; and 
 a conversion unit which retrieves the Internet Protocol packets sequentially from the buffer and converts the Internet Protocol packets into the transport stream packets. 
   
     
     
         19 . A broadcast transport stream distribution method for use in a broadcast transport stream distribution system which distributes broadcast transport streams, in which transport streams of broadcast program contents are packetized, to a user terminal device via a communication line through an Internet Protocol network, the method comprising:
 on a distribution apparatus side, converting transport stream packets having time information of the broadcast transport streams to Internet Protocol packets, while extracting the time information of the transport stream packets from the Internet Protocol packets, detecting fluctuations in a transmission rate of the Internet Protocol packets based on the time information, and controlling the transmission rate of the Internet Protocol packets based on a fluctuation detection result; and   on a user terminal device side, temporarily storing the Internet Protocol packets transmitted via the communication line, and retrieving the Internet Protocol packets sequentially from the stored Internet Protocol packets and converting the Internet Protocol packets into the transport stream packets.   
     
     
         20 . The method according to  claim 19 , further comprising:
 removing NULL packets from the transport stream packets when converting the transport stream packets into the Internet Protocol packets.