[theora-dev] Frame rates in Theora header...

[illiminable]

Aaah ! Nevermind... the byte order is reversed :(

DOH !

Zen.
----- Original Message -----
From: illiminable
To: theora-dev at xiph.org
Sent: Saturday, April 03, 2004 4:39 PM
Subject: [theora-dev] Frame rates in Theora header...

<p>I've got a few theora vids here... and looking at the headers it seems to me
they say they play at 2 frames per second... but watching them they appear
to to play at a faster rate. Theres also some that say they lpay at 1 fps.

Am i missing something here ?

I'm getting the info from here....
http://wiki.xiph.org/TheoraSpec

Is this header structure still valid ?

Heres a dump of the BOS Page..

Ver No      : 0
Head Flags  : 2
Granule Pos : 0
Serial No   : 723674224
Seq No      : 0
Checksum    : 3452830485
Num Segs    : 1
------------------------
Head Size   : 28
Data Size   : 42
Page Size   : 70
Num Packets : 1
------ Packet  0 (42 bytes) -------
00000000: 80 74 68 65 6F 72 61 03 02 00 00 16 00 12 00 01
00000016: 60 00 01 20 00 00 01 7D 78 40 00 0F 42 40 00 00
00000032: 00 00 00 00 00 00 00 00 34 C0
=========================================================

I'm getting the numerator from bytes 22-25 and denom from 26-29

ie.
numerator              denominator
01 7D 78 40          00 0F 42 40

Which gives roughly 1.001 fps.

But looking in the file it looks like it gives roughly 6-8 frames per second
of vorbis audio.

Is there some kind of multiplier i'm missing ?

Cheers.

Zen.

<p>--- >8 ----
List archives:  http://www.xiph.org/archives/
Ogg project homepage: http://www.xiph.org/ogg/
To unsubscribe from this list, send a message to 'theora-dev-request at xiph.org'
containing only the word 'unsubscribe' in the body.  No subject is needed.
Unsubscribe messages sent to the list will be ignored/filtered.