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Any free that can record and edit simultaneously?

  1. May 31, 2008 #1
    VirtualDub is nice for recording and reasonable for editing but it cannot do the two simultaneously. Or can it?

    Any free software that can so the two simultaneously, that is, edit an .avi while it is being recorded?
  2. jcsd
  3. May 31, 2008 #2
    Do you really need this feature ?
  4. May 31, 2008 #3


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    How would it even be possible? I mean, you could play with the volume, and I suppose a quick finger on the pause button would be like marking in and marking out. But what other kind of editing could you possibly be wanting to do during recording? I mean, if you sneeze while twiddling a reverb knob, you're doomed since you've just irrevocably recorded that edit.
  5. Jun 1, 2008 #4
    I just want to remove the adverts. But do it accurately, ie after a commercial break has been recorded.

    Techically it's certainly possible to modify a disk file while another process is writing at the end of the file. Just need to update the .avi header probably with the new length.
  6. Jun 1, 2008 #5


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    Ah. Well then simply a quick finger on the pause button is your answer.
    I do not think this is possible. File compression occurs, among other ways, as compression over time (i.e. any given second is compressed with the second before and after it). You cannot simply snip bits out of an AVI file. You must decompress, run it, edit it and then recompress it.
  7. Jun 1, 2008 #6
    Not if the adverts come in an abrupt manner, you cannot eliminate them cleanly, a little is left from the beginning of the commercial break, and a little is lost from the programme after the end of the break. Offline one would edit a perfectly continuous movie, but with pause you can;t do that. (Dunno how you assumed someone would post this question without knowing about the existence of the pause button but anyway).

    I know, avidemux for example does just that. But compression only ranges between keyframes, every few seconds or so. So it does not have to recompress the entire file, the feature is called smart recompress.

    So someone must have applied the equivalent of this feature on .avi's while another process is appending to them.

    Or perhaps what about that a recorder that produces a large number of short .avi's, while another part of the software edits them transparently to the user (ie the user does not see the many .avi's until they are joined into one at the end)
  8. Jun 1, 2008 #7


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    I would have thought that someone would, but the nature of the question seems to indicate that they do not. :uhh:

    Frankly, my conclusion is that I really don't know what you are asking. If you want to edit out commercials while a video is playing then how else could it be done except with a quick finger on the pause button?

    Or are you simply trying to find a way to edit the early portion of a video as if it were offline while the end of the video is still being recorded?

    Yeah, no. I've worked in live webcasting. If it could be done, we would have been doing it.
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