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<body>Hi Ross,<BR>
<BR>
Maybe you have misunderstood, In fact my "HasItemForH264" variable is set in another thread - the one that handles your H.264 encoding(I mentioned it <BR>
<BR>
in my code).<BR>
<BR>
My problem is "HasItemForH264" variable is set to be non-zero in another thread, but event loop seems not respond immediately, it delay some time ,then<BR>
<BR>
implemented "deliverFrame".<BR>
<BR>
My purpose is implementing the "deliverFrame" as soon as possible when "HasItemForH264!=0".<BR>
<BR>
Thanks for your help :)<BR>
<BR>
<BR>
<BR><BR><BR><BR><BR><BR>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #008080 2px solid; MARGIN-RIGHT: 0px">
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Date: Thu, 1 Feb 2007 08:57:20 -0800<BR>To: live-devel@ns.live555.com<BR>From: finlayson@live555.com<BR>Subject: Re: [Live-devel] "no-blocking fashion" in doGetNextFrame()<BR><BR>
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<BLOCKQUOTE>In doGetNextFrame() member fuction of DeviceSource, I want to call "deliverFrame" in a non-blocking fashion,<BR> </BLOCKQUOTE>
<BLOCKQUOTE>I wrote my code <A href="http://lists.live555.com/pipermail/live-devel/2005-September/003276.html" target=_blank>(follow the example</A> <A href="http://lists.live555.com/pipermail/live-devel/2005-September/003276.html.)" target=_blank><FONT color=#800080><U>http://lists.live555.com/pipermail/live-devel/2005-September/003276.<SPAN></SPAN>html</U></FONT></A>.)<BR> <BR>It works,but another problem came out: it returns immediately when "watchVarible==0"(no data is currntly available),<BR> <BR>but it still wait a long time even "watchVarible" already became non-zero.<BR> <BR>My purpose is implementing the "deliverFrame" as soon as possible when "watchVarible!=0".<BR> <BR>Could anyone help me? Thanks very much!<BR> <BR>Here is my code:<BR> <BR>void DeviceSource::doGetNextFrame()<BR> {<BR> <BR>envforH264->taskScheduler().doEventLoop(HasItemForH264); //Ha<SPAN></SPAN>sItemForH264 is set non-zero in another thread after it filled the buffer <BR><BR> deliverFrame();</BLOCKQUOTE>
<BLOCKQUOTE> }</BLOCKQUOTE>
<DIV><BR></DIV>
<DIV>The problem with this is that - if no new data is currently available - you will be executing the event loop forever, but the "HasItemForH264" will never get set, because nothing will ever call "deliverFrame()".</DIV>
<DIV><BR></DIV>
<DIV>Instead, the solution is for your *other* thread - the one that handles your H.264 encoding - to be the one that sets the "HasItemForH264" variable.</DIV>
<DIV><BR></DIV>
<BLOCKQUOTE> usleep(100);</BLOCKQUOTE>
<DIV><BR></DIV>
<DIV>Don't do this - it will delay the whole application for 100ms, and nothing else will get done during this time.</DIV><PRE>--
</PRE>
<DIV><BR>Ross Finlayson<BR>Live Networks, Inc.<BR>http://www.live555.com/</DIV></BLOCKQUOTE><br /><hr />通过 Windows Live Messenger 表达您自己！ <a href='http://get.live.com/messenger/overview' target='_new'>Windows Live Messenger！</a></body>
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