<META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=gb2312"> <html xmlns:v="urn:schemas-microsoft-com:vml" xmlns:o="urn:schemas-microsoft-com:office:office" xmlns:w="urn:schemas-microsoft-com:office:word" xmlns:x="urn:schemas-microsoft-com:office:excel" xmlns:p="urn:schemas-microsoft-com:office:powerpoint" xmlns:a="urn:schemas-microsoft-com:office:access" xmlns:dt="uuid:C2F41010-65B3-11d1-A29F-00AA00C14882" xmlns:s="uuid:BDC6E3F0-6DA3-11d1-A2A3-00AA00C14882" xmlns:rs="urn:schemas-microsoft-com:rowset" xmlns:z="#RowsetSchema" xmlns:b="urn:schemas-microsoft-com:office:publisher" xmlns:ss="urn:schemas-microsoft-com:office:spreadsheet" xmlns:c="urn:schemas-microsoft-com:office:component:spreadsheet" xmlns:odc="urn:schemas-microsoft-com:office:odc" xmlns:oa="urn:schemas-microsoft-com:office:activation" xmlns:html="http://www.w3.org/TR/REC-html40" xmlns:q="http://schemas.xmlsoap.org/soap/envelope/" xmlns:rtc="http://microsoft.com/officenet/conferencing" xmlns:D="DAV:" xmlns:Repl="http://schemas.microsoft.com/repl/" xmlns:mt="http://schemas.microsoft.com/sharepoint/soap/meetings/" xmlns:x2="http://schemas.microsoft.com/office/excel/2003/xml" xmlns:ppda="http://www.passport.com/NameSpace.xsd" xmlns:ois="http://schemas.microsoft.com/sharepoint/soap/ois/" xmlns:dir="http://schemas.microsoft.com/sharepoint/soap/directory/" xmlns:ds="http://www.w3.org/2000/09/xmldsig#" xmlns:dsp="http://schemas.microsoft.com/sharepoint/dsp" xmlns:udc="http://schemas.microsoft.com/data/udc" xmlns:xsd="http://www.w3.org/2001/XMLSchema" xmlns:sub="http://schemas.microsoft.com/sharepoint/soap/2002/1/alerts/" xmlns:ec="http://www.w3.org/2001/04/xmlenc#" xmlns:sp="http://schemas.microsoft.com/sharepoint/" xmlns:sps="http://schemas.microsoft.com/sharepoint/soap/" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:udcs="http://schemas.microsoft.com/data/udc/soap" xmlns:udcxf="http://schemas.microsoft.com/data/udc/xmlfile" xmlns:udcp2p="http://schemas.microsoft.com/data/udc/parttopart" xmlns:st="" xmlns:st1="urn:schemas-microsoft-com:office:smarttags" xmlns="http://www.w3.org/TR/REC-html40"> <head> <meta name=Generator content="Microsoft Word 11 (filtered medium)"> <base href="x-msg://1/"> <o:SmartTagType namespaceuri="urn:schemas-microsoft-com:office:smarttags" name="PersonName"/>  <style>  </style> </head> <body lang=ZH-CN link=blue vlink=blue style='word-wrap: break-word;-webkit-nbsp-mode: space; -webkit-line-break: after-white-space'> <div class=Section1> <o:p> </o:p> Thanks a lot for your information/suggestion.<o:p></o:p> <o:p> </o:p> And I have made some experiments, and found that: I have to create new GstBuffer for every gst_pad_push() in _chain(), once the GstBuffer is used, it could not push data to downstream element successfully, the pipeline still keeps running, but the data in GstBuffer can’t be written into file.<o:p></o:p> <o:p> </o:p> Please note, I mean I need to create GstBuffer for each call of _chain(), but not the real buffer which will contain real data (GstBufer’s member variable ->data will point this buffer)<o:p></o:p> <o:p> </o:p> What’s the problem?<o:p></o:p> <o:p> </o:p> <div> thanks,<o:p></o:p> Weian<o:p></o:p> </div> <div> <div class=MsoNormal align=center style='text-align:center'> <hr size=2 width="100%" align=center tabindex=-1> </div> From: Clark, Rob [mailto:rob@ti.com] Sent: 2010年1月9日 17:55 To: Discussion of the development of GStreamer Subject: Re: [gst-devel] Question on how to use GstBuffer?<o:p></o:p> </div> <o:p> </o:p> yes, there are a handful of examples of this..  look for example, in v4l2bufferpool..  xvimagesink, etc..<o:p></o:p> <div> <o:p> </o:p> </div> <div> basically the principle is to subclass GstBuffer, provide your own finalize function that revives the buffer and returns it to your pool of buffers.<o:p></o:p> </div> <div> <o:p> </o:p> </div> <div> <o:p> </o:p> </div> <div> (random thought:  really, it's a pattern seen in enough gst elements, that perhaps it would be nice to see a generic GstBufferPool class..)<o:p></o:p> </div> <div> <o:p> </o:p> </div> <div> <o:p> </o:p> </div> <div> BR,<o:p></o:p> </div> <div> -R<o:p></o:p> </div> <div> <o:p> </o:p> <div> <div> <div> On Jan 7, 2010, at 8:56 PM, <st1:PersonName w:st="on">Chen, Weian</st1:PersonName> wrote:<o:p></o:p> </div> <o:p></o:p> <span style='orphans: 2;widows: 2;-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;word-spacing: 0px'> <div link=blue vlink=purple> <div> Hi All,<u1:p></u1:p><o:p></o:p> <u1:p> </u1:p><o:p></o:p> In my current element, I will create and new a GstBuffer (which means to use g_malloc to allocate buffer) in the _chain() function for each frame.<u1:p></u1:p><o:p></o:p> <u1:p> </u1:p><o:p></o:p> My question is: Can I allocate several buffers (ring buffers) ahead of time, then I can re-use them and don’t need to allocate buffer for each call of _chain, if yes, how?<u1:p></u1:p><o:p></o:p> <u1:p> </u1:p><o:p></o:p> Thanks in advanced.<u1:p></u1:p><o:p></o:p> <u1:p> </u1:p><o:p></o:p> Weian<u1:p></u1:p><o:p></o:p> </div> ------------------------------------------------------------------------------ This <a href="http://SF.Net">SF.Net</a> email is sponsored by the Verizon Developer Community Take advantage of Verizon's best-in-class app development support A streamlined, 14 day to market process makes app distribution fast and easy Join now and get one step closer to millions of Verizon customers <a href="http://p.sf.net/sfu/verizon-dev2dev">http://p.sf.net/sfu/verizon-dev2dev</a> _______________________________________________ gstreamer-devel mailing list <a href="mailto:gstreamer-devel@lists.sourceforge.net">gstreamer-devel@lists.sourceforge.net</a> <a href="https://lists.sourceforge.net/lists/listinfo/gstreamer-devel">https://lists.sourceforge.net/lists/listinfo/gstreamer-devel</a><o:p></o:p> </div> </div> <o:p> </o:p> </div> </div> </div> </body> </html>