RTP Payload Format--- Packetization Modes

http://tools.ietf.org/html/rfc6184

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5.4.  Packetization Modes
   This memo specifies three cases of packetization modes:   o  Single NAL unit mode   o  Non-interleaved mode   o  Interleaved mode   The single NAL unit mode is targeted for conversational systems that   comply with ITU-T Recommendation H.241 [3]  (see Section 12.1).  The   non-interleaved mode is targeted for conversational systems that may   not comply with ITU-T Recommendation H.241.  In the non-interleaved   mode, NAL units are transmitted in NAL unit decoding order.  The   interleaved mode is targeted for systems that do not require very low   end-to-end latency.  The interleaved mode allows transmission of NAL   units out of NAL unit decoding order.   The packetization mode in use MAY be signaled by the value of the   OPTIONAL packetization-mode media type parameter.  The used   packetization mode governs which NAL unit types are allowed in RTP   payloads.  Table 3 summarizes the allowed packet payload types for   each packetization mode.  Packetization modes are explained in more   detail in Section 6.      Table 3.  Summary of allowed NAL unit types for each packetization                mode (yes = allowed, no = disallowed, ig = ignore)      Payload Packet    Single NAL    Non-Interleaved    Interleaved      Type    Type      Unit Mode           Mode             Mode      -------------------------------------------------------------      0      reserved      ig               ig               ig      1-23   NAL unit     yes              yes               no      24     STAP-A        no              yes               no      25     STAP-B        no               no              yes      26     MTAP16        no               no              yes      27     MTAP24        no               no              yes      28     FU-A          no              yes              yes      29     FU-B          no               no              yes      30-31  reserved      ig               ig               ig   Some NAL unit or payload type values (indicated as reserved in Table   3) are reserved for future extensions.  NAL units of those types   SHOULD NOT be sent by a sender (direct as packet payloads, as   aggregation units in aggregation packets, or as fragmented units in   FU packets) and MUST be ignored by a receiver.  For example, the   payload types 1-23, with the associated packet type "NAL unit", areWang, et al.                 Standards Track                   [Page 16]

 RFC 6184           RTP Payload Format for H.264 Video           May 2011   allowed in "Single NAL Unit Mode" and in "Non-Interleaved Mode" but   disallowed in "Interleaved Mode".  However, NAL units of NAL unit   types 1-23 can be used in "Interleaved Mode" as aggregation units in   STAP-B, MTAP16, and MTAP24 packets as well as fragmented units in FU-   A and FU-B packets.  Similarly, NAL units of NAL unit types 1-23 can   also be used in the "Non-Interleaved Mode" as aggregation units in   STAP-A packets or fragmented units in FU-A packets, in addition to   being directly used as packet payloads.

5.4.  Packetization Modes
   This memo specifies three cases of packetization modes:   o  Single NAL unit mode   o  Non-interleaved mode   o  Interleaved mode   The single NAL unit mode is targeted for conversational systems that   comply with ITU-T Recommendation H.241 [3]  (see Section 12.1).  The   non-interleaved mode is targeted for conversational systems that may   not comply with ITU-T Recommendation H.241.  In the non-interleaved   mode, NAL units are transmitted in NAL unit decoding order.  The   interleaved mode is targeted for systems that do not require very low   end-to-end latency.  The interleaved mode allows transmission of NAL   units out of NAL unit decoding order.   The packetization mode in use MAY be signaled by the value of the   OPTIONAL packetization-mode media type parameter.  The used   packetization mode governs which NAL unit types are allowed in RTP   payloads.  Table 3 summarizes the allowed packet payload types for   each packetization mode.  Packetization modes are explained in more   detail in Section 6.      Table 3.  Summary of allowed NAL unit types for each packetization                mode (yes = allowed, no = disallowed, ig = ignore)      Payload Packet    Single NAL    Non-Interleaved    Interleaved      Type    Type      Unit Mode           Mode             Mode      -------------------------------------------------------------      0      reserved      ig               ig               ig      1-23   NAL unit     yes              yes               no      24     STAP-A        no              yes               no      25     STAP-B        no               no              yes      26     MTAP16        no               no              yes      27     MTAP24        no               no              yes      28     FU-A          no              yes              yes      29     FU-B          no               no              yes      30-31  reserved      ig               ig               ig   Some NAL unit or payload type values (indicated as reserved in Table   3) are reserved for future extensions.  NAL units of those types   SHOULD NOT be sent by a sender (direct as packet payloads, as   aggregation units in aggregation packets, or as fragmented units in   FU packets) and MUST be ignored by a receiver.  For example, the   payload types 1-23, with the associated packet type "NAL unit", areWang, et al.                 Standards Track                   [Page 16]

 RFC 6184           RTP Payload Format for H.264 Video           May 2011   allowed in "Single NAL Unit Mode" and in "Non-Interleaved Mode" but   disallowed in "Interleaved Mode".  However, NAL units of NAL unit   types 1-23 can be used in "Interleaved Mode" as aggregation units in   STAP-B, MTAP16, and MTAP24 packets as well as fragmented units in FU-   A and FU-B packets.  Similarly, NAL units of NAL unit types 1-23 can   also be used in the "Non-Interleaved Mode" as aggregation units in   STAP-A packets or fragmented units in FU-A packets, in addition to   being directly used as packet payloads.