RTP-based loss recovery and quality monitoring for non-IP and raw-IP MPEG transport flows

• US 8,301,982 B2
• Filed: 11/18/2009
• Issued: 10/30/2012
• Est. Priority Date: 11/18/2009
• Status: Active Grant

• Current Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Original Assignee: Cisco Technology, Inc. (Cisco Systems, Inc.)
• Inventors: Ver Steeg, William C., Begen, Ali C.
• Primary Examiner(s): Guyton, Philip
• Application Number:
  US12/620,779
• Publication Number:
  US 20110119546A1
• Time in Patent Office: 1,077 Days
• Field of Search: 714/776
• US Class Current: 714/776
• CPC Class Codes: H04L 65/611 for multicast or broadcast systems for broadcast or conference H04L12/18; arrangements for broadcast or distribution combined with broadcast H04H20/00; arrangements for broadcast applications with a direct linkage to broadcast information or to broadcast space-time H04H60/00; selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS], H04W4/06
• CPC Class Codes: H04L 65/612 for unicast
• CPC Class Codes: H04L 65/65 Network streaming protocols, e.g. real-time transport protocol [RTP] or real-time control protocol [RTCP]
• CPC Class Codes: H04L 65/70 Media network packetisation
• CPC Class Codes: H04L 65/765 intermediate
• CPC Class Codes: H04N 21/6437 Real-time Transport Protocol [RTP]
• CPC Class Codes: H04N 21/64707 for transferring content from a first network to a second network, e.g. between IP and wireless

Abstract

In one method embodiment, transmitting a transport stream formatted according to a defined coding specification to a receive-and-process (RP) system, the transport stream format further comprising a non-Internet protocol (IP) format or a raw-IP format; providing a mapping stream, the mapping stream correlating the transport stream to a Real-time Transport Protocol (RTP)-formatted data stream that encapsulates the transport stream, the mapping stream comprising identifying information corresponding to the transport stream and second identifying information corresponding to the data stream; and transmitting the mapping stream to the RP system over an IP connection to enable RTP capabilities at the RP system.

Claims

1. A method, comprising:

transmitting over an in-band communication a transport stream formatted according to a defined coding specification to a receive-and-process (RP) system, the transport stream format further comprising a non-Internet protocol (IP) format or a raw-IP format;

providing a mapping stream, the mapping stream comprising identifying information corresponding to the transport stream and second identifying information corresponding to the data stream; and

transmitting the mapping stream to the RP system over an IP connection to enable Real-time Transport Protocol (RTP) capabilities at the RP system, further configuring the RP system to request a channel change based on a retransmission loss repair mechanism over the IP connection, wherein the RP system is configured to provide RTP functionality based on the mapping stream.

2. The method of claim 1, wherein the coding specification is Moving Picture Experts Group (MPEG)-2 compliant.

3. The method of claim 1, further comprising transmitting RTP-encapsulated forward error correction (FEC) packets to the RP system.

4. The method of claim 1, wherein the identifying information comprises an indicator corresponding to one or more of a start of a first byte of an elementary video or audio stream, a system clock reference, a packet identifier, or a continuity counter.

5. The method of claim 1, wherein providing the mapping stream comprises uniquely correlating the identifying information with the second identifying information in the data stream.

6. The method of claim 5, wherein the second identifying information includes a time stamp or a numerical value based on the time stamp.

7. The method of claim 1, wherein providing further comprises compressing the mapping stream, the compression based on one or more of enumerating base identifying information of a first packet of the data stream mapped to a first portion of the raw-IP or non-IP transport stream and referencing identifying information of an additional packet of the data stream as an offset to the base enumeration corresponding to a second portion of the raw-IP or non-IP transport stream, or run-length-encoding of the mapping stream.

8. The method of claim 1, further comprising receiving a retransmission request from the RP system over the IP connection based on packet-level detection of an error in transmission of the video stream.

9. The method of claim 1, further comprising receiving an RTP Control Protocol (RTCP) feedback report from the RP system over the IP connection.

10. The method of claim 1, wherein the raw-IP transport stream comprises IP/User Datagram Protocol (UDP) encapsulation and the non-IP transport stream is devoid of IP/UDP encapsulation.

11. The method of claim 1, further comprising encapsulating the non-IP or raw-IP transport stream to derive the RTP-formatted data stream.

12. The method of claim 1, wherein the non-IP or raw-IP transport stream is embodied as a single program transport stream or a transport stream comprising multiple programs.

13. The method of claim 1, wherein the mapping stream comprises a data structure having a sequence number of the RTP encapsulated packet and the PID and continuity counter of the correlated portion of the non-IP or raw-IP transport stream.

14. A system, comprising:

a Real-time Transport Protocol (RTP) encapsulator comprising one or more processors comprising encapsulation logic, the encapsulation logic capable of RTP encapsulating non-Internet Protocol (IP) flows and raw-IP flows, the RTP encapsulator further configured to generate a mapping stream that correlates respective identifying information of packets in the non-IP flows or raw-IP flows with RTP packets of the RTP encapsulated non-IP or raw-IP flows, the non-IP flows comprising non-encapsulated Moving Picture Experts Group (MPEG)-2 transport stream (TS) flows, the raw-IP flows comprising IP/User Datagram Protocol (UDP)/MPEG2TS flows, the mapping stream delivered over an IP connection to a receive-and-process (RP) system, the RTP encapsulator further configured to optionally provide RTP-encapsulated forward error correction (FEC) packets to the RP system; and

a server communicatively coupled to the RTP encapsulator, the server comprising;

retransmission/repair logic configured to facilitate correction of video or audio transmission errors by retransmitting corrected packets encapsulated in RTP for corresponding lost or corrupted packets, wherein the server is further configured to locally store the mapping stream, and responsive to a reception of an auxiliary stream comprising transport-level identifying information corresponding to lost or corrupted packets received at the RP system and transport-level identifying information corresponding packets preceding the lost or corrupted packets, synchronizing the lost or corrupted packets with RTP packets based on the mapping stream, and causing the transmission of packets comprising a retransmission of good packets corresponding to the lost or corrupted packets.

15. The system of claim 14, wherein the mapping is from transport stream cells to RTP packets on a 1:

1 basis.

16. A system, comprising:

a receive-and-process (RP) system comprising one or more processors capable of receiving a non-Internet Protocol (IP) media content stream and a raw-IP media content stream each carried as a transport stream over an in-band communication and configured to receive a mapping stream over an IP connection, the RP system further configured to synchronize the non-IP or raw-IP media content stream with a Real-time Transport Protocol (RTP) data stream based on first and second identifying information of the media content stream and the data stream, respectively, the mapping stream comprising the first and second identifying information, the RP system incapable of receiving RTP-encapsulated transport stream flows and configured to provide RTP functionality based on the mapping stream, wherein the RP system is further configured to request a channel change based on a retransmission loss repair mechanism over the IP connection.

17. The system of claim 16, wherein the RP system is further configured to perform one or more of the following RTP functionality:

responsive to detection of a video or audio transmission error, generate an RTCP feedback report for transmittal upstream of the RP system, the feedback report identifying a portion of the video or audio stream corresponding to the video transmission error;

request an RTP-encapsulated retransmission over the IP connection based on detection of the video or audio transmission error;

or forward error correct the portion based on reception of RTP-encapsulated forward error correction (FEC) packets over the IP connection.