<html><head><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"></head><body><div><br></div><div>sorry if this client top posts, but to answer, you can do 1 of 2 things. assume it is different and insert it before returning to the unprocessed clip. or you can check if they are different by doing a comparison.</div><div><br></div><div><br></div><div id="composer_signature"><div style="font-size:85%;color:#575757" dir="auto">Sent from my T-Mobile 4G LTE Device</div></div><div><br></div><div style="font-size:100%;color:#000000"><!-- originalMessage --><div>-------- Original message --------</div><div>From: YIRAN LI <mrfun.china@gmail.com> </div><div>Date: 4/7/17 3:15 PM (GMT-08:00) </div><div>To: "This list is about using libavcodec, libavformat, libavutil, libavdevice and libavfilter." <libav-user@ffmpeg.org>, FFmpeg user questions <ffmpeg-user@ffmpeg.org> </div><div>Subject: [Libav-user] re-encoding and transcode (codec copy) on same file. </div><div><br></div></div><div dir="ltr"><div class="gmail_default" style="font-family:georgia,serif">Hi guys,</div><div class="gmail_default" style="font-family:georgia,serif"><br></div><div class="gmail_default" style="font-family:georgia,serif">I'm investigating if it's possible to do editing and transcode on same file.</div><div class="gmail_default" style="font-family:georgia,serif"><br></div><div class="gmail_default" style="font-family:georgia,serif">I mean use -vcodec copy, we can readout packets and write them directly into output file without re-encoding. But if it's possible, for example if I have a 2 mins video, re-encode 1st min because there're some effects applied to that region but copy 2nd part?</div><div class="gmail_default" style="font-family:georgia,serif"><br></div><div class="gmail_default" style="font-family:georgia,serif">My concern is, for example we know H.264 has extradata, if I re-encode first part but keep 2nd part, how if new extradata is different from old extradta?</div><div class="gmail_default" style="font-family:georgia,serif"><br></div><div class="gmail_default" style="font-family:georgia,serif">Anyone have suggestion on this? and any other possible problems doing this?</div><div class="gmail_default" style="font-family:georgia,serif"><br></div><div class="gmail_default" style="font-family:georgia,serif">Thanks</div></div>
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