Subject: Re: [linux-audio-dev] [ardour] custom graphics + MIDI control for LADSPA plugins
From: Paul Barton-Davis (pbd_AT_Op.Net)
Date: Sat Nov 25 2000 - 03:32:44 EET
>For example plugins could request a certain datatype (let's say
>arour's HDR engine want 24bit integer samples) Other plugins would
>prefer to work in the float domain. Other plugs want to work with
>16bit samples. In this case the host would make more datatypes
>available for plugins, than the soundcard is capable of. (by doing
>conversions).
As far as I am concerned, this is a broken model. Plugins should use
ONE standard data type.
Yes, I think we should take the high road
some day and support non-linear-amplitude data streams the way that
CSound does (spectral data etc.). We'd be a big step ahead of VST if
we could do that.
But in the linear time domain I have nothing but concern about "some
plugins want Y, some want X". They get amplitude data in a format that
we (the API designer's) have decided is adequate. If their coder's
don't like it, tough.
>You may say that this might take long time to design and that we
>prefer the egg today rather than the chicken tomorrow (at least in
>italy we have this saying)). I agree , but in that case I'm
>prefering using monolithic apps like ardour which can act as a host
>for plugins, rather than developing some quick-n-dirty virtual studio
>model which over the long term turns out to have many flaws that we
>cannot get rid of (since there already tons of apps relying on this
>model).
Ardour *requires* a "quick and dirty virtual studio model" to work as
intended. I have no choice.
>I think this topic need further research and especially we need to know
>what does complex audio apps (like ardour) really need to know/setup.
You can just read the source of alsa_device.{cc,h} and
alsa_hardware.{cc,h} in the ardour sources.
>What I have in mind is something that overcomes VST's limitations so that
>a host can host ANY kind of audio app, not just DSP or synth modules.
there are, as far as i can see, only a few types of audio "apps":
ones that accept input and do generate any output (simple recorders)
ones that generate output and do accept any input (simple
synthesis, players)
ones that accept input and generate output (real recorders, fx,
complex synthesis)
i can't think of any other categories. you could make this a bit more
complex by considering MIDI and other data streams as well, i suppose.
--p "accepts MIDI input, generates audio output"
This archive was generated by hypermail 2b28 : Sat Nov 25 2000 - 04:23:27 EET