Re: [ecasound] edl-light ?

New Message Reply About this list Date view Thread view Subject view Author view Other groups

Subject: Re: [ecasound] edl-light ?
From: Kai Vehmanen (k_AT_eca.cx)
Date: Mon Nov 26 2001 - 01:00:24 EET


On Tue, 13 Nov 2001 xavier.moulet_AT_free.fr_AT_free.fr wrote:

> being a delighted user of ecasound, I would like to know if reading a edl-like
> file has ever been considered.

two ideas have been floating around:

- adding support for Ardour's edl-format - this should be quite
  straighforward task, just needs someone to do it
- extending the ewf-format (see my previous message); basicly the
  current ewf-format is like a "one object edl" :)

> In fact, what I am missing is basically the ability to specify a file, and a
> list of (file, starting time in file, length, number of loops) elements in a
> file, and let ecasound play those elements sequentially. That would make me

Yes, ewf actually lets you specify one files, starting time, length and
loop on/off, so it's pretty close to your definition.

> May it be easy to extend the ecasound own fileformat to do this ? I _really_
> think that would be a simple, useful feature. Technically, I don't know if
> opening/seeking N files can be long, but as it is only replay, we could use
> some quite large buffers.

This is not a problem. Ecasound's disk i/o subsubsystem (-z:db in ecasound
2.0, enabled by default in 2.1/2.2), takes care of this for all
non-realtime audio objects.

> What do you people think ? I have taken a look at ecasound implementation, and
> I think that the most difficult thing may be to implement a library.

Basicly you just need to write a new AUDIO_IO object, and that's it. The
interface is well-defined (see ecasound/libecasound/audioio.h), which
makes the task easier.
 
ecasound/libecasound/audioio-ewf.cpp should be a good starting point.
All the "edl-magic" is contained in EWFFILE::read_buffer() function
(called by the ecasound engine to produce one buffer of audio).

-- 
 http://www.eca.cx
 Audio software for Linux!

-- To unsubscribe send message 'unsubscribe' in the body of the message to <ecasound-list-request_AT_wakkanet.fi>.


New Message Reply About this list Date view Thread view Subject view Author view Other groups

This archive was generated by hypermail 2b28 : Mon Nov 26 2001 - 00:53:27 EET