<html><head><meta http-equiv="Content-Type" content="text/html charset=us-ascii"></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space;"><div><blockquote type="cite"><div style="line-height: 1.7; font-size: 14px; font-family: arial;"><div><span class="Apple-tab-span" style="white-space:pre"> </span>I saw the DeviceSource code in live555 project.</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>I found that the the fPresentationTime would be set by gettimeofday when doGetNextFrame is called.</div><div><span class="Apple-tab-span" style="white-space:pre"> </span>I remembered you said the fPresentationTime must be same at the first time, <span style="line-height: 1.7;"> So how should it sync audio and video? </span></div></div></blockquote><div><br></div></div>If the "fPresentationTime" value is accurate, and aligned with 'wall clock time' (the time that you'd get by calling "gettimeofday()"), then audio/video synchronization will happen automatically - see <a href="http://www.live555.com/liveMedia/faq.html#separate-rtp-streams">http://www.live555.com/liveMedia/faq.html#separate-rtp-streams</a><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; "><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>Live Networks, Inc.<br><a href="http://www.live555.com/">http://www.live555.com/</a></span></span>
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