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Synthesizing multiple 1GB4 SDIFs in one sound file

AudioSculpt
#1

Hi all,

as an AudioSculpt 3.1.9 user, I have a question concerning the SuperVP CLI: how should look like the command line in order to synthesize multiple 1GB4 SDIFs concatenating them one after another seamlessly in one single sound file? Thanks in advance for your kind concern.

Best regards,

Francesco Vitale

#2

Hi Francesco,

To be sure about your question :
1 - Do you want to concatenate the SDIF files ? Or
2 - concatenate the results of your synthesized audio in one single file

Best,
Charles

#3

Dear Charles,

I’d need to concatenate the SDIF files, if possible with a little overlap (to achieve a seamless continuity).

Best,

Francesco

#4

Hello Francesco

you cannot do concatenation in SuperVP. Fo this you would have to load the SDIF file in your favorite environment (Python, Matlab, …)
and do the concatenation yourself. This is not straight forward however.

  1. SuperVP has a special handling for the first frame. This frame normally serves only to reproduce the first signal segment, all the frequencies that
    are stored there are somewhat tweaked and will not work well when you concatenate them into a continuous sequence. So certainly you should skip the first frame in all but the first segment.

  2. SuperVP derives the frame step from the analysis position that is the sdif frame time position. To get a coherent frame step between all the concatenated sdif frames you need to adapt all frame times of the sdif frames that are concatenated by means of replacing the frame time position by the time position of the previous frame increased by the analysis step that corresponds to the analysis step in the concatenated sdif file.

Note, that you cannot overlap the sdif frames, but the sdif frames have overlap anyway, because they have
been produced by means of an analysis with overlap. So normally you should not need to add extra overlap, besides fixing the time positions as described above.

Best
Axel