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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span lang=EN-GB>Hi all,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB> I’m streaming H264 video from a number of webcams to other users over the internet. For the most part this works fine. However, occasionally I get a number of frames with the got_picture_ptr of avcodec_decode_video2() set to 0. This results in a slight pause in the received stream of a couple of seconds. It happens fairly regularly but not sufficiently to render the experience unusable. I’ve noted that there have been a few previous posts regarding what the meaning of having the flag set to 0 actually signifies, but I haven’t come across a definitive answer. The documentation states that it signifies the frame couldn’t be decompressed, but what actually causes this to happen?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>I’m obviously dropping packets as the data is going over a public network and I’m using RTP to stream the data, so that’s to be expected. Is it just a case of not receiving all the frames in a given picture and hence the decoder is struggling to decode the complete picture? All things such as timestamps appear to be OK.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>I’m using x264 to encode the data and am using intra-refresh to encode, so I don’t get reference (IDR) frames as such, but I do get fragmented NAL’s.<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>Can anybody shed some light on this or suggest an approach when the situation occurs?<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>Many thanks,<o:p></o:p></span></p><p class=MsoNormal><span lang=EN-GB><o:p> </o:p></span></p><p class=MsoNormal><span lang=EN-GB>Tony.</span><o:p></o:p></p></div><br/>
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