<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 style="font-family: 微软雅黑; font-size: 14px; font-style: normal; font-variant: normal; font-weight: normal; letter-spacing: normal; line-height: 21px; orphans: auto; text-align: start; text-indent: 0px; text-transform: none; white-space: normal; widows: auto; word-spacing: 0px; -webkit-text-stroke-width: 0px;" class=""><div style="font-family: 微软雅黑, Tahoma;" class=""> I use <span style="background-color: rgba(0, 0, 0, 0); font-size: 10.5pt; line-height: 1.5;" class="">live.2015.05.28.tar.gz. use live555MediaServer.cpp as rtsp server. I have a HD h.264 stream , the nal unit is SPS,PPS,IDR,P,P,P.... I use openRTSP.exe and test RTSPClient.exe to receive the stream. Both client receive SPS, PPS, P, P..they all didn't receive IDR frame. their size is 32Bytes , 8 Bytes, 403709Bytes, 21937Bytes 9619Bytes...... . The output log of the two clients shows they don't received I frame.</span></div></div></div></blockquote><div><br class=""></div></div>The problem is that your I-frame (IDR) NAL unit is excessive large (403709 bytes). This has two problems:<div class="">1/ The receiving RTSP client does not have - by default - a large enough buffer to receive a NAL unit of this size. You can increase this buffer size - e.g., in “openRTSP” using its "-b <buffer-size>” option.</div><div class="">2/ More importantly, the problem with NAL units this large is that they get fragmented into an extremely large number of RTP packets (in this case, at least 270 RTP packets). *All* of these RTP packets have to be received at the far end; if even *one* of these RTP packets gets lost, then the entire NAL unit will be unrenderable - i.e., useless. It is very likely that this is what has happened in your case.</div><div class=""><br class=""></div><div class="">A much better solution is to reconfigure your encoder so that it breaks up very large ‘I-frame’ NAL units like this into multiple ‘slice’ NAL units. This will make your stream much more tolerant of packet loss.</div><div class=""><br class=""></div><div class="">This is an issue that I’ve commented on several times before:</div><div class=""><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="http://lists.live555.com/pipermail/live-devel/2011-December/014190.html" class="">http://lists.live555.com/pipermail/live-devel/2011-December/014190.html</a></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="http://lists.live555.com/pipermail/live-devel/2012-August/015615.html" class="">http://lists.live555.com/pipermail/live-devel/2012-August/015615.html</a></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="http://lists.live555.com/pipermail/live-devel/2013-May/016994.html" class="">http://lists.live555.com/pipermail/live-devel/2013-May/016994.html</a></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="http://lists.live555.com/pipermail/live-devel/2014-June/018426.html" class="">http://lists.live555.com/pipermail/live-devel/2014-June/018426.html</a></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="http://lists.live555.com/pipermail/live-devel/2014-June/018432.html" class="">http://lists.live555.com/pipermail/live-devel/2014-June/018432.html</a></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="http://lists.live555.com/pipermail/live-devel/2014-June/018433.html" class="">http://lists.live555.com/pipermail/live-devel/2014-June/018433.html</a></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="http://lists.live555.com/pipermail/live-devel/2014-June/018434.html" class="">http://lists.live555.com/pipermail/live-devel/2014-June/018434.html</a></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="http://lists.live555.com/pipermail/live-devel/2015-March/019135.html" class="">http://lists.live555.com/pipermail/live-devel/2015-March/019135.html</a></div><div class=""><span class="Apple-tab-span" style="white-space: pre;"> </span><a href="http://lists.live555.com/pipermail/live-devel/2015-April/019228.html" class="">http://lists.live555.com/pipermail/live-devel/2015-April/019228.html</a></div></div><div class=""><br class=""></div><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>
</div>
<br class=""></body></html>