<html><head><meta http-equiv="Content-Type" content="text/html charset=utf-8"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;" class=""><div><blockquote type="cite" class=""><div class=""><div dir="ltr" class="">I am trying to implement a media server to stream also live sessions constructed 'on the fly'.<div class="">Analyzing the behaviour of DynamicRTSPServer contained in live555MediaServer, I noted that when a client demand a stream to the server (i.e a 264 stream file), lookupServerMediaSession is called twice, both with isFirstLookupInSession = true.</div><div class="">What is the meaning of this double call?</div></div></div></blockquote><div><br class=""></div>The first call to “lookupServerMediaSession()” is done (by the server) to implement the RTSP “DESCRIBE” command.</div><div><br class=""></div><div>Subsequent calls to "lookupServerMediaSession()” are done to implement the RTSP “SETUP” command - for each media track (audio, video, etc.) in the stream. (Note that if a stream contains both an audio track and a video track, then there will be a RTSP “SETUP” command for each.) In this case, the first call to "lookupServerMediaSession()” (for the first track) has the “isFirstLookupInSession” parameter as True. Any other calls to "lookupServerMediaSession()” (for subsequent tracks) will have the “isFirstLookupInSession” parameter as False.</div><div><br class=""></div><div>The purpose of this code was to ensure that streaming from multi-track files works properly.</div><br class=""><br class=""><div apple-content-edited="true" class="">
<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; "><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; ">Ross Finlayson<br class="">Live Networks, Inc.<br class=""><a href="http://www.live555.com/" class="">http://www.live555.com/</a></span></span>
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