[vorbis] streaming ogg audio

[Akos Maroy]

TIMMERMANS ANDRE wrote:
> Yes but the file duration of an mp3 file is generally easy to determine:
> - for non-VBR files you derive a good estimation from the file size
>   (from figyu's case I figure it's just winamp downloading files of known size)
>   and the bitrate. I have never seen it differ more than a fraction
>   of a second for 10-15mins files (the same cannot be said for
>   ogg files, I made the test).

Yes, this is true: CBR mp3 files can be seeked into by offset 
calculations based on the sample rate

> - VBR files usually come with a file header which provides
>   the duration of the file.

for the duration, yes. but you can't seek into it into a certain 
position easily. e.g. you can't say: I want to listen from the 10th 
minute of this file.

> Also Winamp may maintain a copy of the file on disk in which case
> it can seek freely within the already downloaded part of the mp3 file,

would you do this with mp3 files of several 10MBs?

> it could also be done for an ogg file but without the file duration
> how is winamp going to display a seek bar.

the problem with ogg is that it is inherently a VBR format. but the ogg 
libraries provide a way to seek into them.

The main problem is that as you have nothing but a generic web server on 
the server side, you would have to do all these things by means of HTTP 
requests. I don't see how this could be done easily.

Another approach would be to use icecast or a similar server on the 
server side. Then special requests could be made. For this one would 
have to make developers of icecast & popular players aggree on the 
format of these special requests.

<p>Akos

<p>--- >8 ----
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