Blue Cat's Plug'n Script - Phase Shift using FFT?
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- KVRer
- Topic Starter
- 6 posts since 9 Jan, 2015
Does anybody know how to perform phase shift on audio samples? I need 90 degree phase shift. The only phase shift I am able to perform is 180, which is simple multiplication of -1.
I'm afraid that other phase shift is possible only using FFT. How can I do it in Plug'n Script?
Thanks!
I'm afraid that other phase shift is possible only using FFT. How can I do it in Plug'n Script?
Thanks!
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Blue Cat Audio Blue Cat Audio https://www.kvraudio.com/forum/memberlist.php?mode=viewprofile&u=39981
- KVRAF
- 5819 posts since 8 Sep, 2004 from Paris (France)
Hi,
You could implement an FFT directly in the script, but I am not sure about the performance...
If you are fine with an approximate method, I think you could emulate it using a network of IIR allpass filters. searching "hilbert networks 90 degrees" on Google should help you find more information about this topic. I guess that's for your Dolby decoder?
You could implement an FFT directly in the script, but I am not sure about the performance...
If you are fine with an approximate method, I think you could emulate it using a network of IIR allpass filters. searching "hilbert networks 90 degrees" on Google should help you find more information about this topic. I guess that's for your Dolby decoder?
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- KVRer
- Topic Starter
- 6 posts since 9 Jan, 2015
Thanks for reply, I already read some info about hilbert networks, but as my goal is to implement Dolby Prologic II encoder, I need phase under control Thats why I asked about FFT.
But as I am totally new to DSP programming (I have some common programming skills), I need a guide how to code it in Plug'n'script. I haven't found any api reference to your functions and implementing my own fft would not be efficient.
I know performance might be an issue, but I don't intend to sell this
Thanks for any further info!
But as I am totally new to DSP programming (I have some common programming skills), I need a guide how to code it in Plug'n'script. I haven't found any api reference to your functions and implementing my own fft would not be efficient.
I know performance might be an issue, but I don't intend to sell this
Thanks for any further info!
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Blue Cat Audio Blue Cat Audio https://www.kvraudio.com/forum/memberlist.php?mode=viewprofile&u=39981
- KVRAF
- 5819 posts since 8 Sep, 2004 from Paris (France)
Phase shift will indeed be an issue here!
There is currently no fft function exposed to the scripts. If performance is not a problem, you can try to copy/paste any FFT algorithm and see if it works fast enough.
There is currently no fft function exposed to the scripts. If performance is not a problem, you can try to copy/paste any FFT algorithm and see if it works fast enough.