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Re: Is GetMovieTime() reliable?
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Re: Is GetMovieTime() reliable?

> At 6:14 PM -0800 2/17/02, Kevin Marks wrote:
>> QT usually will derive this timing from the samplerate of sound
>> playback, so if you are using the computer's clock as an external
>> reference to compare with, you may be seeing the drift of your sound
>> card against its notional samplerate.
>
> The answer was to slave my own clock component to the movie's clock,
> instead of the other way around. The sound card's output clock is
> asynchronous with respect to the computer's clock, and the time in
> the sound track will drift progressively by varying amounts on
> different computers.
>
> It just about drove me crazy.
> --Al Evans--
> --

I don't know if I can do something like that, since I am generating new data
(from the user) based on what he is hearing. So I'm not slaving anything
that already exists against something else.

Right now I'm thinking about inserting pauses every 30 seconds or so,
stopping the quicktime movie and restarting it at the same place so that my
drift gets reset. It's totally inelegant for the user, but that user is
just me and at least I would end up with a synch'ed soundtrack...
Bob
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