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<p class="MsoNormal"><span style="color:black">I forgot to say that I’m using Gstreamer 0.10 (and its python bindings).<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black">Moreover, Today I implemented a version that makes use of appsrc (that can’t seek) and got the very same results: audio is always fine, video works only if it’s not mixed with audio.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
<p class="MsoNormal"><span style="color:black">Interestingly I have no problems when decoding VP8 pcaps.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="color:black"><o:p> </o:p></span></p>
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<p class="MsoNormal"><b>From:</b> gstreamer-devel [mailto:gstreamer-devel-bounces@lists.freedesktop.org]
<b>On Behalf Of </b>Danilo Gasques Rodrigues<br>
<b>Sent:</b> Wednesday, July 16, 2014 10:51 AM<br>
<b>To:</b> gstreamer-devel@lists.freedesktop.org<br>
<b>Subject:</b> fdsrc or filesrc with pipes/fifos odd behavior with mp4mux<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Hello all,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I have a pipeline for reading two pcaps, decoding them and mixing them to a .mp4 file:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> filesrc location=video.pcap ! pcapparse ! (**) ! ffenc_mpeg4 ! mux.<o:p></o:p></p>
<p class="MsoNormal"> filesrc location=audio.pcap ! pcapparse ! (*)! audioconvert ! lamemp3enc ! mux.
<o:p></o:p></p>
<p class="MsoNormal"> mp4mux name=mux ! filesink location=output.mp4<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">(**) equals to “ application/x-rtp, payload=96 ! rtph264depay ! video/x-h264 ! h264parse ! decodebin ! videoscale ! video/x-raw-yuv, width=640, height=480 “
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">(*) equals to application/x-rtp, payload=9, clock-rate=8000 ! rtpg722depay ! ffdec_g722<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It works fine when video.pcap and audio.pcap are regular files.
<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Oddly enough, I have problems when the video input is a FIFO like this:<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> mkfifo video<o:p></o:p></p>
<p class="MsoNormal"> cat video.pcap > video &<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">By using it, the output is a .mp4 with audio and video streams, but the video will never decode (mplayer doesn’t play, vlc plays only the sound). I tried to use fdsrc with a pipe and I get the very same result.<o:p></o:p></p>
<p class="MsoNormal">Interestingly, I can use either filesrc with a fifo or fdsrc with a pipe for the audio and it just works.<o:p></o:p></p>
<p class="MsoNormal">Finally, if I’m to encode video alone it works perfectly fine with both methods of input.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Looking at gstreamer debug logs I couldn’t spot any difference between using filesrc with a regular and filesrc with a fifo.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Does anyone have a hint of how could I solve this problem? I tried using queues after filesrc with no success at all!
<o:p></o:p></p>
<p class="MsoNormal">I think it’s somewhat related to the fact that one can’t fseek a pipe/fifo, but I can’t understand why it would work for the video alone but not when mixing audio and video.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks in advance,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Danilo<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal"> <o:p></o:p></p>
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