[Speex-dev] Ogg embedding, problem with spec and/or bugs in speexenc

Joe Wreschnig piman at sacredchao.net
Sat Jul 15 12:17:22 PDT 2006

(Sending again after subscribing, I guess the moderator is on vacation.)

I'm working on support for tagging Speex files for Mutagen[0] and part
of the specification at [1] is confusing me. It says the first page
should have granulepos 0 and packetno 0. Does this really mean page
sequence number 0, since the Ogg format doesn't number packets?

If it doesn't mean page sequence number, what does it mean?

If it does really mean packet, does that mean there are no guarantees
about page/packet boundries? e.g. Vorbis guarantees the first page
contains only, and entirely, the first packet. speexenc breaks pages
after the info and comment packets, which again suggests "pages" rather
than "packets" is meant.

Later it says that the audio data starts at packetno 2. Does this really
mean page number 2? If so, does that mean the comment packet cannot span
multiple pages? I can force speexenc to write a multipage comment
packet, which would indicate either speexenc is wrong or the spec is

It says the comment packet should have granulepos 0. However, when I
force a multipage comment packet, all but the last page have granulepos
-1. Regardless of the above, I believe this is a speexenc bug. Either it
should mark all these pages 0, or only allow one page.

[0] http://www.sacredchao.net/quodlibet/wiki/Development/Mutagen
[1] http://www.speex.org/manual2/node7.html#SECTION00073000000000000000
Joe Wreschnig <piman at sacredchao.net>
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