<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; "><div>(I've corrected the "Subject:" line of this email thread to make it more accurate.)</div><div><br></div>The "auxSDPLine()" virtual function is used - by the "OnDemandServerMediaSubsession" implementation - when setting up the SDP lines that describe the substream. In particular, it is used to set up a special 'extra' SDP line (usually beginning with "a=fmtp:") that *some*, but not all, media codecs need to describe the stream. Its default implementation simply queries the "RTPSink" object for this value (and the "RTPSink", by default, will just return NULL).<div><br></div><div>The bottom line is that you - as someone who defines and implements an "OnDemandServerMediaSubsession" subclass - will *not* need to reimplement this virtual function, unless:</div><div>1/ The codec that you are using is one that needs a special extra "a=fmtp:" SDP line, *and*</div><div>2/ This special extra SDP line can't be obtained simply by querying the "RTPSink" object.</div><div><br></div><div>Conditions 1/ and 2/ are usually true only for when you're streaming codecs like H.264 or MPEG-4 video that require special 'configuration' parameters, *and* those special 'configuration' parameters are available only 'in band'. For example, if you're streaming a H.264 or MPEG-4 Elementary Stream video file.</div><div><br></div><div>Because your codec is MP3, you definitely *do not* need to reimplement the "getAuxSDPLine()" virtual function. I.e., if you have such a reimplementation, then you should remove it.</div><br><br><div apple-content-edited="true">
<span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; "><span class="Apple-style-span" style="border-collapse: separate; color: rgb(0, 0, 0); font-family: Helvetica; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: normal; orphans: 2; text-align: -webkit-auto; text-indent: 0px; text-transform: none; white-space: normal; widows: 2; word-spacing: 0px; -webkit-border-horizontal-spacing: 0px; -webkit-border-vertical-spacing: 0px; -webkit-text-decorations-in-effect: none; -webkit-text-size-adjust: auto; -webkit-text-stroke-width: 0px; font-size: medium; ">Ross Finlayson<br>Live Networks, Inc.<br><a href="http://www.live555.com/">http://www.live555.com/</a></span></span>
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