[vorbis-dev] Header

[Adam Whitehead]

Hi,

I don't know if this is possible, or fits in with your plans for the format,
but with OggVorbis would it be possible to add a simple header,
such as that in the first frame of an MP3 file with information encoded
such as bitrate, samplerate etc.

This would simplify things greatly from the perspective of people
developing utilities such as playlist editors, search engines etc.
especially if it was in the first few bytes of the file. (for example, it
saves a lot of bandwidth for me in most cases having to only download
the first 4 bytes of an MP3 file [for the first frame header] and the last
128 bytes [for ID3]).

Now that the bitstream format is finalised, does that mean an addition
like this would not be possible?

Regards,
Adam Whitehead
Netherworld Media
E-mail: adam at nwmedia.com.au
Phone: +61 (889) 279 898
FAX: +61 (889) 273 889
AudioPhilez (http://www.audiophilez.com)

----- Original Message ----- 
From: "Monty" <xiphmont at xiph.org>
To: <vorbis-dev at xiph.org>
Sent: Saturday, May 13, 2000 6:00 AM
Subject: Re: [vorbis-dev] Header 

> 
> > If you could provide me with brief details on the location/encoding of
> > the info within the files, I can get started writing the PHP script I need for
> > this to add OGG support to AudioPhilez.
> 
> Magic to detect Ogg (and detect Ogg/Vorbis) is easy.  Extracting the details of
> the file takes more effort because Ogg and Vorbis generally don't bound field
> lengths if possible.  The headers will need to be parsed (First the Ogg pages
> need to be parsed, then the first three packets extracted from however many
> pages they take up.  Then these header packets can be parsed).
> 
> Whipping up docs for this now.
> 
> > Is the source for this easy enough to understand? I'm hardly
> > an accomplished C/C++ programmer but if it is straightforward enough
> > and commented, I should be able to get something happening in PHP.
> 
> It's easy to deal with, you just need to know that there is more than one layer
> of parsing.  First at the Ogg bitstream level, then at the Vorbis packet level.
> 
> Monty
> 
> 
> 
> --- >8 ----
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> 

--- >8 ----
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