Using Vamp Plugins and Hosts > Host Forum: Sonic Visualiser

Align File Timelines issue

(1/1)

Miranda:
Hi,

I seem to be having some issue with aligning timelines of three files I'm comparing in visualiser.

So far I've
1. imported 3 sound files (2 wav, 1 mp3)
2. inserted the barlines on each by tapping
3. reset the bar numbering to start from 1 on each, using simple counter
4. pressed the align button

The app then processes files 2 and 3 and a little while later they show as aligned.

However...

When I subsequently play them and swap from one to the other, they are clearly not aligned as, e.g. song 2 comes in at a different point from where song 1 left off.

I had assumed that the processing would synchronise the bar lines, and any difference in tempo would be automatically allowed for by compressing the slower tempo pieces.  Am I mistaken or have I missed something in the documtentation?

These are not classical pieces, they are jazz standards with very different tempos - I'm not sure if that is significant.

Any guidance will be greatly appreciated.

Miranda

cannam:
Miranda,

The align timelines feature is completely "unsupervised" -- all it does is feed the audio data to an alignment plugin based on the MATCH alignment method, which aligns the files automatically.  It isn't possible to help it along by inserting bar lines yourself; it will always make its own judgment about how the audio data align.  I think (although I may have misunderstood) that this may be the cause of your confusion/complaint.

(As a matter of interest, SV doesn't actually stretch or squash the audio when alignment is in effect, either -- it always plays one file at a time when the files are aligned, and just keeps track of whereabouts in the other file would correspond to the current play position so that it can switch to the "correct" point when you change the current pane.)

I agree, it would be nice to have a method that does what you describe -- taking a set of bar line positions for two separate recordings and adjusting the audio to suit.  But I'm afraid that SV can't currently do that.


Chris

Navigation

[0] Message Index