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Are the sprop-parameters or profile level identifier an SDP parameter needed for H264 decoding?

I am trying to understand what is required in SDP in order to be able to decode H264 from RTP packets.

This is due to this question , since the answer to this question only works in a small number of cases.

Example

I pass the following command from VLC.

vlc -vvv sample_video/big_buck_bunny_480p_h264.mov --sout '#transcode{vcodec=h264,vb=700,fps=20,scale=0.25,acodec=none}:rtp{dst=10.5.110.117,port=5004,ttl=1}'

This transcodes the video to:

  • Bitrate: 700 Kbps
  • Frame Rate: 20 per second
  • Resolution: 25% of the original

The receiver correctly receives and interprets the stream with the next SDP file (delete the first line, its just the name).

//test.sdp
c=IN IP4 10.5.110.117
m=video 5004 RTP/AVP 96
a=rtpmap:96 H264/90000
a=fmtp:96 profile-level-id=640014;sprop-parameter-sets=Z2QAFKzZQ0R+f/zBfMMAQAAAAwBAAAAKI8UKZYA=,aOvssiw=;

Command to run: vlc test.sdp

An accessible document here , entitled "SIP Video File Best Practices" in chapter 7.2 for level-level conditions:

( ) RFC 6184, " -id" , , . SDP, . , 420010, RFC 6184.

, sprop-:

sprop-parameters-sets

H.264 , . SIP- , H.323 SIP- .

1

, profile-level-id .

//test.sdp
c=IN IP4 10.5.110.117
m=video 5004 RTP/AVP 96
a=rtpmap:96 H264/90000
a=fmtp:96 sprop-parameter-sets=Z2QAFKzZQ0R+f/zBfMMAQAAAAwBAAAAKI8UKZYA=,aOvssiw=;

sprop-parameter-sets.

2

RTCP, SIP SAP, SDP sprop-parameter-sets.

  • ,
  • , ,
+2
1

:

profile-level-id, . , , 3 , profile, level, . , , , ...

sprop-parameter-sets , . , , , . , , . , sdp, . .

1:

, profile-level-id , - , 420010. , , , , . , 42 Constrained Baseline Profile (CBP), 64 SDP High Profile (HiP).

, sprop-parameter-sets , , , vlc , , , .

2:

SIP sprop-parameter-sets , . h264 Wireshark, .

+3

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