On Thu, 2008-06-05 at 22:36 +0100, Andy Farnell wrote:
And conversely, a delay buffer with a ordinary movable read point (which is what I guess you really want in this case) will always cause a click since there's no reason why jumps between arbitrary samples will be smooth. Of course there will be no trasposition since the read location changes instead of the rate.
Transposition may be desirable, but clicks rarely are. As it stands you can either have smoothness with transposition, or no transposition and clicks.
iirc, there is a technique described in millers book, which i don't recall the name of, which is used to avoid discontinuities, when jumping from one to another time point in an audio stream. this is achieved by adding a ramp to the signal, that smoothes out the difference between the samples at the jump. i used this technique to create clickless loops with arbitrary length. i assume, it would also work for a non-continuous, but clickfree changeable delay (without transposition).
however, if jamie wants it to be continuous, then probably the technique as shown in 3.audio.examples/I07.phase.vocoder.pd could be used, which is very cpu-time consuming, though.
roman
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