Re: [Audacity-devel] Redesigning effect dialogs

[Anthony A. O. <ai...@gm...>]

On Tue, 26 Oct 2004 20:11:09 +0100, James Crook wrote:


>Instead of the user explicitly commanding a partial-pre-render,
>we can use 'idle time' to cache pre-renders.  If advanced users don't 
>like this, they can switch off the feature.  For those users who spend 
>most of their time working near the top of the effects stack, this will 
>be a significant win.

Partial pre-renders are a nice idea, in that they let the user do work and
not just look at a progress bar. Realtime stuff, well it remains to be seen
if this is indeed practical.


>> This emilinates _the_ great value of realtime... hearing your changes
>> instantly as an integral part of the workflow.  Otherwise, it's just
>> batch with a fancier UI: 'twiddle, OK, listen, cancel, undo, twiddle,
>> OK, listen, cancel, undo..."

>I hear you, and I'm not proposing to eliminate the ability to twiddle
>values whilst a render is in progress.  

>If the effect renders faster than you play, then you get 
>conventional real-time effects which you can listen to and twiddle
>values as you do so.

>If the effect renders slower than you play, then you still get an 
>enhanced 'batch mode', at least enhanced compared to the
>batch mode currently available in Audacity.  You won't be able to 
>play back the effect in real time, but no program could, without 
>more CPU.

>The enhancements over normal batch mode are:
> - You can start using the audio before the render is complete.
> - You can twiddle a parameter e.g. an automation control point,
>    whilst the effect is rendering in batch mode.  Audacity will 
>    need to re-render some chunks, if it has already rendered
>    that section, but that's all.

Watch your disk fragmentation here. A temp space on another disk would be a
good solution to this.


> - You can layer additional effects over a batch mode operation
>    that is still in progress.
> - You can twiddle real time values in the effect layered over 
>    the batch mode effect, whilst the batch mode 
>    effect is still rendering - and can listen to the results as you 
>    do so for those parts of the batch mode effect that have 
>    been rendered so far.

>Are these standard in other programs?

Sort of. There's no such thing in Protools, but the function called
"Freeze" by Logic and Cubase/Nuendo let's you sort of render out a track
and undo/redo that process.

The background rendering is usualy a standard function in Sound Forge and
Vegas, but it isn't used as you propose.


>These 'enhancements' come from using enhanced real time 
>effects code to drive batch mode.  We have an effects stack, and 
>we're keeping track of cached chunks of sound, whether we're in 
>batch or real time mode.  

Good luck on the logistics of this. It's very convenient thing to have. It
would certainly let me do more work when rendering out lots of stuff on one
track, and I'll still be able to cut stuff on another.

There are some effects that are not realtime, running in a session in an
insert, so that's a third category. Many effects of this type in the
Protools world work as an Audiosuite plugin, which are offline effects.
Pitch- and timestretchers are amongst them, so don't forget to include
those in your batch-type cue.

Thumbs up for that idea.

 Tony