On Wed, 2010-11-24 at 17:06 +0100, Derek Holzer wrote:
Hi Samuel,
probably the bandlimited oscillator BLOSC objects in the creb library, or the spliced-transition method found in the Pd help files or Miller's book would be the best things, however I have also included a chapter in the FLOSS Manual on using the "sinsum" message to create rudimentary waveforms:
http://en.flossmanuals.net/PureData/GeneratingWaveforms
They are bandlimited, however they still alias at higher frequencies. Combining them with oversampling could also be an interesting idea:
On 11/24/10 4:50 PM, samuel rowe wrote:
band-limited waveforms (using fourier synthesis, then writing this into a table)
This is the approach those abstraction use: https://github.com/reduzent/pd-bloscabs
And unlike what Derek stated, this does _not_ necessarily produce aliasing artefacts. The abstractions from bloscabs use sinesum tables dependent on the incoming frequency. So they are completely aliasing-free there is no need for oversampling or such.
In fact, the [creb/blosc~ saw] produces (not very loud, though) aliasing artefacts.
The spliced-transition method is particularly interesting for making anti-aliased pulse waveforms with dynamically adjustable pulse width.
Roman