On 6/4/20, Till Bovermann <lf...@lfsaw.de> wrote: > Dear list, > > I am currently trying to implement 1bit-synthesis mechanisms in faust and > have some sketches on how to implement that: > > It basically boils down to interpret a stream of integers (of a given > bit-depth, say, 32bits) as a stream of blocks (of size 32) of bits. > > This is quite close to hardware interfaces such as the i2s implementation of > the esp32 [1], which has native capabilities to transmit PDM (pulse density > modulation, aka DSD, aka 1-bit audio) [2]. > > > the technical implementation would be to create a series of > 1-bit-block-specific operations (primitives) that could handle the basics of > such dsp. This would particularly mean to create a 1-sample delay operator, > i.e. an operator that turns the bitstream > > > 10110101... > > into > > 010110101... > > > I discovered the `ffunction` primitive that allows to integrate foreign > functions into the language, however, AFAICS (and according to sletz on > slack, and from what I got from the documentation at [3]), they need to be > stateless. > > the aforementioned 1-bit delay, though, requires a state (of one additional > integer). > > > does anyone know if there is a possibility to implement such a (1-sample) > delay as a primitive in faust? > > > all the best and thanks for your thoughts > > Till > > [1] > https://www.espressif.com/sites/default/files/documentation/esp32_technical_reference_manual_en.pdf > [2] search e.g. for "pdm" in this article > https://hackaday.com/2019/04/18/all-you-need-to-know-about-i2s/ > [3] https://faust.grame.fr/doc/manual/index.html#ffunction > > _______________________________________________ > Faudiostream-users mailing list > Faudiostream-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/faudiostream-users >
I can't tell whether this would be useful to your case, but could you declare a static variable, c-side, within your foreign function? This allows some kind of state to be held between calls to that function. _______________________________________________ Faudiostream-users mailing list Faudiostream-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/faudiostream-users
