Re: [music-dsp] Sampling theorem extension

2015-06-11 Thread Sampo Syreeni
On 2015-06-09, Ethan Duni wrote: The Fourier transform does not exist for functions that blow up to +- infinity like that. To do frequency domain analysis of those kinds of signals, you need to use the Laplace and/or Z transforms. Actually in the distributional setting polynomials do have

Re: [music-dsp] Sampling theorem extension

2015-06-11 Thread Vadim Zavalishin
On 11-Jun-15 11:00, Sampo Syreeni wrote: I don't know how useful the resulting Fourier transforms would be to the original poster, though: their structure is weird to say the least. Under the Fourier transform polynomials map to linear combinations of the derivatives of various orders of the

Re: [music-dsp] Sampling theorem extension

2015-06-11 Thread vadim.zavalishin
Sampo Syreeni писал 2015-06-11 15:55: On 2015-06-11, Vadim Zavalishin wrote: So they can be considered kind of bandlimited, although as I noted in my other post, it seems to result in DC offsets in their restored versions, if sinc is windowed. Not really, if the windowing is done right. The

[music-dsp] [ot] other than sampling theorem, Theo

2015-06-11 Thread Sampo Syreeni
On 2015-06-11, Theo Verelst wrote: [...] I don't recommend any of the guys I've read from here to presume they'll make it high up the mathematical pecking order by assuming all kinds of previous century generalities, while being even more imprecise about Hilbert Space related math than

Re: [music-dsp] Sampling theorem extension

2015-06-11 Thread Sampo Syreeni
On 2015-06-11, vadim.zavalishin wrote: Not really, if the windowing is done right. The DC offsets have more to do with the following integration step. I'm not sure which integration step you are referring to. The typical framework starts with BLITs, implemented as interpolated wavetable

Re: [music-dsp] [ot] other than sampling theorem, Theo

2015-06-11 Thread robert bristow-johnson
On 6/11/15 1:20 PM, Sampo Syreeni wrote: On 2015-06-11, Theo Verelst wrote: [...] I don't recommend any of the guys I've read from here to presume they'll make it high up the mathematical pecking order by assuming all kinds of previous century generalities, while being even more imprecise

Re: [music-dsp] FFTW Help in C

2015-06-11 Thread Danny van Swieten
When setting up the audio callback for PortAudio you can give it a void* to some data. Set up the fft plan and set the fft object as the void*. In the callback you can use a cast to get the fft object from the void* Good luck Sent from my iPhone On 11 Jun 2015, at 16:20, Connor Gettel

Re: [music-dsp] Sampling theorem extension

2015-06-11 Thread Theo Verelst
HI While it's cute you all followed my lead to think about simple continuous signals that are bandwidth limited, such that they can be used as proper examples for a digitization/synthesis/reconstruction discipline, I don't recommend any of the guys I've read from here to presume they'll make

Re: [music-dsp] FFTW Help in C

2015-06-11 Thread Richard Dobson
If it is purely for graphic display, the interesting aspect coding-wise will be timing, so that the display coincides closely enough with the audio it represents. In this regard, the update rate for a running display rarely needs to be more than 60 fps, and can often be slower - so you would

Re: [music-dsp] Sampling theorem extension

2015-06-11 Thread Vadim Zavalishin
On 10-Jun-15 21:26, Ethan Duni wrote: With bilateral Laplace transform it's also complicated, because the damping doesn't work there, except possibly at one specific damping setting (for an exponent, where for polynomials it doesn't work at all), yielding a DC Why isn't that sufficient? Do you

Re: [music-dsp] Sampling theorem extension

2015-06-11 Thread robert bristow-johnson
On 6/11/15 5:39 PM, Sampo Syreeni wrote: On 2015-06-09, robert bristow-johnson wrote: BTW, i am no longer much enamoured with BLIT and the descendents of BLIT. eventually it gets to an integrated (or twice or 3 times integrated) wavetable synthesis, and at that point, i'll just do

Re: [music-dsp] FFTW Help in C

2015-06-11 Thread Phil Burk
Hello Connor, If you just wanted to do a quick FFT and then using the spectrum to control synthesis, then I would recommend staying in the callback. If you are doing overlap-add then set framesPerBuffer to half your window size and combine the current buffer with the previous buffer to feed into

Re: [music-dsp] FFTW Help in C

2015-06-11 Thread Athos Bacchiocchi
You may find this article useful: http://www.rossbencina.com/code/real-time-audio-programming-101-time-waits-for-nothing It deals with the things to do and not to do when processing audio in realtime using callbacks. Athos On 11 June 2015 at 16:20, Connor Gettel connorget...@me.com wrote: