Vorbis - Feb 2002 - Seeking in a saved stream; or, Why isn't that sucker valid?

I hope that this is the appropriate venue for this question.  If it's not,
let me know and I'll take it elsewhere (perhaps vorbis-dev).

Saved streams are great - it lets this norteamericano get his fill of BBC Radio
1's Essential Mix.  Unfortunately, saved streams aren't seekable. 
Running ogginfo on the stream data gives:

erial=1626603590
header_integrity=pass
vendor=Xiphophorus libVorbis I 20011231
version=0
channels=2
rate=44100
bitrate_upper=none
bitrate_nominal=128031
bitrate_lower=none
stream_integrity=fail
stream_truncated=true
header_integrity=fail

Reported length varies; Winamp seems to think this is 6653:18 in length, while
most tools think it has zero length.

One would think that, seeing as the stream decodes nicely, it should be fairly
simple to clean up the stream's headers so that it is possible to seek
within the stream.  This would have the added benefit of making it possible to
edit the stream in traditional editors.

Of course, I'm not a programmer, so I don't really know how difficult it
would be to do this - just that it would be a bit beyond my skill.  (I did take
some programming in college, but you don't want to see my output.)  I just
wondered if anyone has already done this for their own benefit, or if anyone
feels like picking it up as a project.  For listening to a 2+ hour stream,
it's annoying to be forced to listen straight through - play or pause,
nothing else.

And if this is a really simple topic that has been covered before, please
forgive me.  I've Googled, I've asked a forum or two, and I've
searched the archives of vorbis and vorbis-dev.  I've even read the
documentation of the format to see if I could figure it out myself. 
Unfortunately, I can't, so I hereby (rather unceremoniously) drop this in
the laps of They Who Ought To Know These Things, in hopes that They have a
brilliant bit of code for me.

Oh, and OS is irrelevant to the code, if you're so inclined.

TIA.

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On Mon, 11 Feb 2002, Stephen Commiskey wrote:
> I hope that this is the appropriate venue for this question.  If it's
not, let me know and I'll take it elsewhere (perhaps vorbis-dev).
> 
> Saved streams are great - it lets this norteamericano get his fill of BBC
> Radio 1's Essential Mix.  Unfortunately, saved streams aren't
seekable.
> Running ogginfo on the stream data gives:
> stream_integrity=fail
<p>This line in the ogginfo output concerns me.  It means that there are
actually
damaged Ogg packets in the stream.  How are you saving this stream to disk?

I think there is a problem here, but not with seeking, exactly.  If the file
is saved on disk, then it should be seekable.  It is possible that vorbisfile
is not acting correctly when given damaged streams of the sort you have.


---
Stan Seibert

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On Mon, Feb 11, 2002 at 02:53:07PM -0600, Stephen Commiskey
wrote:
> I hope that this is the appropriate venue for this question.  If it's
not, let me know and I'll take it elsewhere (perhaps vorbis-dev).
> 
> Saved streams are great - it lets this norteamericano get his fill of BBC
Radio 1's Essential Mix.  Unfortunately, saved streams aren't seekable. 
Running ogginfo on the stream data gives:
> 
> serial=1626603590
> header_integrity=pass
> vendor=Xiphophorus libVorbis I 20011231
> version=0
> channels=2
> rate=44100
> bitrate_upper=none
> bitrate_nominal=128031
> bitrate_lower=none
> stream_integrity=fail
> stream_truncated=true
> header_integrity=fail
                   ^^^^
odd one there.  But if it were true, it couldn't play.
> Reported length varies; Winamp seems to think this is 6653:18 in length,
while most tools think it has zero length.
Vorbisfile should be able to seek any file, and this is the lib mearly
all apps actually use.  Mail an example to me (a meg or under please)
and I'll fix it (or identify what the problem really is).

Monty

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