Subject: Re: [linux-audio-dev] protux, stereo and interleaving
From: Richard Dobson (rwd_AT_cableinet.co.uk)
Date: Fri Feb 09 2001 - 18:34:06 EET
Fair enough - what file format do they use though? It is a public one?
How do you stream/play the thing, if you have to get through 40mins of
channel one, to get to the start of channel 2? Can you do it with
'ordinary' disks? This is the big argument, about streaming formats v
archive formats. For example, WAVE is streaming, SDIF is archive.
Richard Dobson
Paul Davis wrote:
>
> >frames are interleaved by audio channel. Overall, interleaved data seems
> >much more generic, and real-time friendly. Is it really such a
> >performance-killer - the time to [de]interleave data is a knats-p in a
> >millpond compared to doing 600+ FFTs in real-time...
>
> true. but if you store a 40 minute 24 channel recording in interleaved
> format, editing it becomes extremely difficult, even with
> non-destructive techniques. destructive techniques would require
> rewriting all 24 channels at and beyond the location of any deletion.
> non-destructive techniques can avoid the rewrite, but you end up
> either doing massive amounts of duplicate data i/o and/or using a very
> complicated caching system between the file and the presentation
> system.
>
> i don't think its a coincidence that most high end audio software
> suites use non-interleaved storage formats.
>
> and as someone else pointed out, SIMD encourages this approach as
> well. i'm not sure that we have any good SIMD-capable compilers at
> this time, but thats just a detail :)
>
> --p
-- Test your DAW with my Soundcard Attrition Page! http://www.bath.ac.uk/~masrwd (LU: 3rd July 2000) CDP: http://www.bath.ac.uk/~masjpf/CDP/CDP.htm (LU: 23rd February 2000)
This archive was generated by hypermail 2b28 : Fri Feb 09 2001 - 19:01:48 EET