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View Full Version : A lot of trouble playing some .ogg's... bad header?

UrbalT
6th February 2004, 05:32
I have some Ogg Media files that, I would assume, contain audio and video, at least, although their extension is .ogg (an older standard, maybe?).

I can't get them to play, and I'm set up to play ogm's. I downloaded GSpot, and it gives me garbage for the codecs used, etc.--and OGMInfo (for win32) can't recognize the streams. It seemed like it was a bad header or something, so I decided to open on of these files in a hex editor. Here is the beginning of the file (in ascii, newlines added for readability):

OggSCz,5videoXVID4???OggSF5>{5
audio20004?????]OggSC(?vorbisogmtools v1.0.3
OggS?vorbisogmtools v1.0.3OggSEj
? ?g PQaY??mm
?mm?mm?mm?mm?m

(and in hex):

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

(it repeats that pattern (6DFE6DB7F9B) for a while, but I did not copy it).

Now, it looks to me that these files are using XviD video and Vorbis audio--so the only problem would appear to be the header. Does anyone know how I can fix the header, or if there is some splitter I can use that can read it? By the way, I'm using OggDS.

If anyone needs it, I can try to give more information, but I don't know what else would be useful.
ChristianHJW
6th February 2004, 10:31
Maybe some Ogg Theora files, created with the alpha tools on Linux ?
UrbalT
6th February 2004, 17:04
I don't think so--it was the splitter that was having trouble, and I thought that was independant of the actual codecs used.
echo
6th February 2004, 19:59
I don't know what the problem might be, but could you try remuxing the file to matroska and see if works?

regards
echo
Koepi
6th February 2004, 22:41
Well, instead of remuxing to matroska, you could open the file with vdubmod and see if it has problems parsing the file. If it hasn't, hit "direct stream copy" in the video options and save as OGM again.

Regards
Koepi
UrbalT
7th February 2004, 03:30
VirtualDubMod crashes ("An out-of-bounds memory access (access violation) occurred in module 'VirtualDubMod'.") when it tries to parse the files.

I'm going to see if I can try to get a linux distro on my system, and then look into ogmtools.
ChristianHJW
7th February 2004, 07:01
Originally posted by UrbalT I'm going to see if I can try to get a linux distro on my system, and then look into ogmtools.

Mosu's mkvmerge is the advanced version of it, using the same OGM parser. Unfortunately, if your headers are gone i dont think this will really help you a lot ....
UrbalT
7th February 2004, 22:46
Originally posted by ChristianHJW
Mosu's mkvmerge is the advanced version of it, using the same OGM parser. Unfortunately, if your headers are gone i dont think this will really help you a lot ....

I couldn't get mkvmerge to work, but after going through the ogmtools changelog, I've decided to try the latest version--it looks like pre-1.1 versions created bad headers, but the latest version can fix them.

I've been trying to get ogmtools to compile under cygwin, but since I don't really know what I'm doing, I'm not getting very far (can't even get libogg to compile...). I'm just gonna install debian and download the binaries--unless anyone here wants to compile or has win32 binaries for ogmmerge 1.2?

Consider this problem solved.
echo
8th February 2004, 14:02
Originally posted by UrbalT
unless anyone here wants to compile or has win32 binaries for ogmmerge 1.2?

Take a look here (http://cyrius.bunkus.org/ogmtools.html)

regards
echo

EDIT: I'm sorry I just noticed that latest version there is v0.9a5...:(