Subject: [MMUSIC] question about H.264 SDP Grammer

From: Woo Johnman <[email-masked]>
Date: Fri, 13 Jan 2012 14:34:21 +0800

Hi,
   I have  a H.264 SDP sample whose fmtp attribute is as following:
  "a=fmtp:109 profile-level-id=428014;max-mbps=11880;max-fs=396;"

  As usual,last parameter(max-fs) should not be appended with ';'
  But I am not sure if it is also legal with ';'?

Woo,

Best Regards!

---

From: Tom Kristensen <[email-masked]>
Date: Fri, 13 Jan 2012 22:20:35 +0100

>   But I am not sure if it is also legal with ';'?

When building your SDP there's no reason for adding the last semicolon.

However, as always you need to be liberal in what you accept. When
parsing and decoding the SDP you should tolerate this trailing
semicolon as well as presence of space/blanks between the parameters.

The SDP spec in RFC 4566 has left the actual content of a=fmtp to the
different RTP payload specs.
The RTP payload spec. (RFC 6184 for H.264) only states the a=fmtp
parameter/value list to be "a semicolon-separated list of
parameter=value pairs".
So, whether the trailing semicolon is legal or not isn't too relevant
- is it? You should cope with it!

-- Tom

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