[Gambas-user] Managing soundtracks, WAVs

[Jean-Yves F. Barbier]

Rolf-Werner Eilert a écrit :
...
> At this time, as far as my own needs are concerned, it would be ok if it 
> had a "set to zero position" button and "start". The tricky thing would 
> be following the signals from the projector and keeping the soundtrack 
> synchronised to them. If there was a playback speed option, it would 
> make things somewhat easier. Without it, you will have to correct the 
> position from time to time, resulting in little "jumps" or "stutter" of 
> the sound.

This is quite a nonsense unless you have another track that indicates where
is the next possible jump (usually @ the beginning of a music measure) - in
case it is music, for speech there's no solution.

> Many years ago, in the time of i386 machines, I programmed a similar 
> thing under DOS with PowerBasic, but as far as I remember, I never found 
> an easy way of reading the impulses, and of course I missed an app for 

Use the parallel port, or on some machines (if it already exists) the swi 
switch/connector.

> mixing the soundtrack as it exists today. But playing a soundtrack at 
> varying speeds wasn't that difficult, even varying by only a few percent.

You can't do that unless you're varying *very* slowly, otherwise the result
will be terribly audible.

What you could do is testing the shifting (and it timing) you can apply on
a particular music (the earing difference also depends on frequencies you
have in music) and determine a windows of opportunity in which you can
go to next dia (before or after the normal point).
You can also prepare a lot of music (same drum beat) and mix them in ~0.7s
to avoid speed drifting.

Anyway you'll go into this way will be a PITA because you take the problem
upside down.

-- 
If dolphins are so smart, why did Flipper work for television?