<html><body><div style="color:#000; background-color:#fff; font-family:times new roman, new york, times, serif;font-size:12pt"><SPAN style="RIGHT: auto">
<DIV style="RIGHT: auto" dir=ltr>>>Okay, that's helpful. But then how and where and by what program is <BR>>>timebase calculated? Do the ffmpeg tools calculate it? I don't see <BR>>>how they can. They'd have to look at every frame in the video and<BR>>>that could take a very long time.<BR>><BR>>You should know that video formats reserve some space for metadata. And a portion is dedicated to describe track properties like >VBR/CBR, total time length and so on.<BR style="RIGHT: auto">>FFmpeg relies on those metadata to initiate everything but then can recompute some on the fly, some other tools allows to actually >calculate those track metrics directly from track content, it's safer but slower of course.<BR></DIV>
<div></div>
<DIV style="RIGHT: auto" dir=ltr> </DIV>
<DIV style="RIGHT: auto" dir=ltr>Let's say my input file is 500 GB and was generated by my capture card. Robert</DIV>
<DIV style="RIGHT: auto" dir=ltr>said the timebase member in ffmpeg structs hold the maximum granularity of all the timestamps.</DIV>
<DIV style="RIGHT: auto" dir=ltr>I'm wondering how that can be true. It would take a very long time for ffmpeg to read</DIV>
<DIV style="RIGHT: auto" dir=ltr>500 GB of data to figure out the maximum granularity of all timestamps, and that would</DIV>
<DIV style="RIGHT: auto" dir=ltr>definitely be noticeable. Something else must happen.</DIV>
<div style="RIGHT: auto"><BR style="RIGHT: auto" class=yui-cursor></SPAN></div>
<div style="RIGHT: auto"><BR></div>
<DIV style="FONT-FAMILY: times new roman, new york, times, serif; FONT-SIZE: 12pt">
<DIV style="FONT-FAMILY: times new roman, new york, times, serif; FONT-SIZE: 12pt"><VAR id=yui-ie-cursor></VAR> </DIV></DIV></div></body></html>