Matt said:
> Is it me, or my computer?  Is there something I can do at this end to
> rectify the problem?  If anyone has any ideas please reply off list, if you
> like...
>
> Thanks!
>

I'll allow this on the list for a little while, since I'm answering it. ;-)

It could be your computer, or it could be your internet connection, or it
could be both.  Unless the video producer was just wildly incompetent, the
sound was in synch in the video file that was posted.

The problem comes from the coding and decoding (or compression and
decompression) that have to be done to shove all that information through such
a small pipe.  YouTube uses "streaming", meaning that you start watching the
video before your computer has received the whole thing.  Your computer is
receiving a stream of data of audio and video mixed together.  It has to
separate it out into two distinct streams of audio and video, and then it has
to run each one through a decompression/decoding program (called a codec) that
reconstructs the sound from the audio track and the picture from the video
track.

If your computer is a little on the slow side, the video codec may lag behind
because it's got more to think about.

If your internet connection is also a little on the slow side, the video will
suffer first, because it's at the bottom of the chain: of course the combined
signal has to be divided, and once it's divided, the audio codec takes a lot
less time to do its job than the video codec does, because it has a lot less
to think about.

One solution to some streaming videos is just to watch them twice in a row. 
The second time around often the computer recognizes that you've already
watched it and that it's already stored it, so it just plays it back instead
of downloading it again.

Boy, ask a Audio for Digital Media instructor a question, get a lecture.  I'll
shut up now.

Alden


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