High quality audio morphing effect plugin, why it doesn't exist yet?

[brandtsegg]

Hmmm no I'm afraid a simple preset morph would only volume-cross fade between the two presets, and not truly and harmonically morph into each other.

Ok, guess you would have to automate the parameters between presets then.... Only not sure if it would be worth the time, that's gonna be really messy...

... something like Hadron then? It does truly interpolate the parameter values and the modulator routings when morphing between states. Now, as mentioned, a convincing morph between two recorded input sounds is probably still a way off. Deciding which characteristic features of the two sounds to use to create a perceptually smooth transition is something that requires human intervention with knowledge of the chosen processing technique and how the technique will affect/preserve/distort the chosen features of each sound. But, hey, yeah, an interesting topic for further research.

[valhallasound]

i think i'll start a thread about it over at reaktor board where discussions stay productive and technical (mostly)
fft geeks are welcome to join in.

Not to divert the thread into a technical direction - oh wait, I'm actually fine with this.

Anyway: FFT in Reaktor. How does this work? My last heavy lifting in Reaktor was in 2003, and I didn't know that there was FFT support in there.

To my mind, Max/MSP is the "classic" visual programming environment for working with FFTs, with Pure Data being the "ugly, but free and runs everywhere" choice. Someone with fairly basic Max/MSP skills could probably code up a simple magnitude/interpolator fairly quickly. Of course, Max/MSP no longer runs as a plugin, so Reaktor would be a better way of getting things into your DAW.

what you need is amplitude/frequency, which can't be resynthesised by iFFT, only in an additive way.

Amplitude/frequency can ABSOLUTELY be resynthesized by iFFT. You just need to convert the values from the polar domain back to the rectangular domain. Most FFT processing uses iFFT for efficiency.

That being said, using a bank of sinusoidal oscillators allows for more robust manipulations of the amplitude/frequency data. It is easy to shift the output frequencies, just by multiplying the oscillator frequency. The results might be weird, as the time varying amplitude data carries a lot of the pitch information as well, but the point is that a sine oscillator bank can be really fun to control with information from phase vocoding analysis.

Sean Costello

[monas]

Anyway: FFT in Reaktor. How does this work? My last heavy lifting in Reaktor was in 2003, and I didn't know that there was FFT support in there.

There were some FFT building blocks introduced into Reaktor Core i think in 2006/7 plus some user mods have been made to them to offer bigger frame sizes. Unfortunately there isn't many UL uploads that make use of them. They are a bit clumsy to use and only offer double overlaps (afaikt), but they work fine. Also core doesn't deal with samples "blockwise" like PD/Max does, which sometimes makes FFT easier to grasp in PD/Max. Apart from that Reaktor offers all that PD/Max offers, FFT/iFFT, poltovec/vectopol, and so on, and it puts it all right into your DAW.
Here's a spectral delay i made using Reaktor FFT:
http://co.native-instruments.com/index. ... chid=12159

Amplitude/frequency can ABSOLUTELY be resynthesized by iFFT. You just need to convert the values from the polar domain back to the rectangular domain. Most FFT processing uses iFFT for efficiency.

The problem is just that there's a lot of conversion involved, because if you want to compute the frequencies, you need to have the phase differences first, then calculate the deviation from the bin frequency from that and add the corresponding bin frequency. On the way to there you lose the absolute phases. If you want to make your way back after processing the frequencies now, you need to convert to phase differences again and calculate the running phase, then IFFT. But you can't do anything you like to process the frequency data for some reason i don't fully understand. As you said, an additive resynthesis is much more flexible.

For the morphing i found a way around this problem. What i am using instead of the frequencies is the phase deviations which i interpolate. Then i feed it right back into the running phase calculation and into the IFFT. I finished it up today, and the morpher works perfectly fine. I'll share it soon.

But what i was actually working on is to get the additive synthesis happening in Reaktor, so everyone can have some fun with FFT in Reaktor and stretch and shift things without any maths involved.

[pdxindy]

hmmm...
there's plenty of articles that were posted on the issue of morphing here.
i don't believe that the "fact" that you can't get a consistent and good result from a morphing tool is the reason why developers haven't invested in it. i think it's simply because it's a kind of processing that's too exotic. why run a risk when there's easier money elsewhere?

As soon as you create a morphing tool that gives a consistent and good result, you will disprove that 'fact'. Until then, it stands as the factual reality. There currently is no such tool.

[ChamomileShark]

interesting discussion. I'm wondering if when/if this eazymorph plugin is produced at low, low prices it will still be one of those things that is difficult to create something that is musically useful without a fair amount of work. Maybe it's less about the technology.

In the meantime I'll be trying Neon's suggestions for morphing in Alchemy published in another subforum (thanks for that).

btw, anyone else tried Hadron as a couple of people suggested?

finally thanks Monas for the Reaktor spectral delay, I look forward to trying that later.

[VariKusBrainZ]

This link might be useful

http://csounds.com/node/1485

Its for python scripts that turn any Csound CSD into a VST, supposedly.
As Csound is probably the Daddy of FFT it could be useful to someone.

[Ah_Dziz]

i've just been playing around with the morphing in alchemy again and I think it can do a pretty damn decent job of morphing between relatively complex sounds. Basically if the resynthesis sounds natural the morph will also. anybody want to send me two files for a demonstration?

[kmatheussen]

Try mammut. It uses one FFT for all the sound, so it doesn't reduce sound quality (no windows), and it has 5 different ways to morph sounds (Look under "Load & Multiply").

http://archive.notam02.no/arkiv/doc/mammut/

[arkmabat]

Hmm this makes me think of the morphing hihats in a few Angels and Airwaves songs...

[sandbags]

Try mammut. It uses one FFT for all the sound, so it doesn't reduce sound quality (no windows), and it has 5 different ways to morph sounds (Look under "Load & Multiply").

http://archive.notam02.no/arkiv/doc/mammut/

This looks a potentially interesting app but... what the hell were they thinking with that moving background? I cannot imagine a more distracting thing to do except possibly to have it play sound effects also. Oh wait no they do that too.

Update: Okay I found the prefs button. In my defence I think I would have seen it more easily if not for being distracted by the background and sound effects!

Kind regards,

Matt

[kmatheussen]

I looked briefly for a way to turn that stuff off and didn't find one. Do you know if there is one?

Kind regards,

Matt

You could try to press the "Prefs" button...

[sandbags]

Thanks, found that just as you were writing.

[kmatheussen]

Thanks, found that just as you were writing.

Good to hear. I was hired to brush up the interface for the program. Before, it looked like this:


But perhaps I went a little bit far.

[sandbags]

Sorry, I may have gone a bit overboard in my criticism. Minus the background and sound effects what you've done looks very much better than your screenshot of the original. As a Mac user I'm frequently caught out by non-standard UI: my expectation is preferences in the menubar. I didn't think to look for a prefs button on the page and found it kind of hard to see.

Some interesting effects here. Kudos for explaining what some of them are doing!

Kind regards,

Matt

[cron]

Mammut is great, but can't do audio morphing as far as I'm aware. It has some nice options for creating and combining spectra, but as it FFTs everything into one giant window it's not the best choice for effects which evolve over time AFAIK.

Someone mentioned FScape earlier. Again, great program, but not capable of morphing to my knowledge. The whole general purpose Fourier translation part of it is a bit mysterious and difficult to understand to me. It creates wav files (!) and I'm not really sure what to do with them or how to go about further processing them. Well, not without resorting to speculatively hacking them up with traditional time-based methods then resynthesising that is.