Changing OGM's FourCC

[Mikele]

I don't know if it's called FourCC in this case. I have a couple of OGMs that contain XviD video, but they were made using the DIVX FourCC, and I'd like to change it to XVID so I can use its own filter. I've tried hex-editing the OGM and changing those 4 chars but it ended up being not playable at all. Is there any utility for OGM that does the same like AviC does for AVIs?

[Neo Neko]

No util like that to my knowledge. Dump the video to an AVI with graphedit and change it there then mix it back in the OGG.

[Mikele]

I see. So, for the time being, is there any way to convert a Divx/Vorbis OGM to AVI? I've tried different graphs, but the AVI muxer won't accept the direct audio stream from OGG splitter. It always inserts a Vorbis Decompressor in between, and I would like to keep the original audio instead of recompressing it.

[slavickas]

just mux only video stream to avi change fourcc and mux back to ogm

[Mikele]

Yes, that's clear, but what I'm trying now is to convert an OGM to AVI. I'm sure this is possible, as there is a Vorbis ACM filter to use Vorbis sound in AVIs. But I'm still trying to demux the Vorbis stream succesfully.
Yes, I know this is not a nice question to ask in a forum filled with OGM fans :)

[slavickas]

Originally posted by Mikele
Yes, that's clear, but what I'm trying now is to convert an OGM to AVI. I'm sure this is possible, as there is a Vorbis ACM filter to use Vorbis sound in AVIs. But I'm still trying to demux the Vorbis stream succesfully.
Yes, I know this is not a nice question to ask in a forum filled with OGM fans :)

i think vorbis ACM filter is not compatible with Tobias ds filter

[ProfDrMorph]

just create an AVI File without sound and when you remux it to Ogg you also have to add File Source and Ogg Splitter to include the Ogg file you want to change. Take the video stream from the AVI file and the Vorbis stream ( connect Ogg Splitter directly to Ogg Multiplexer. This works without problems on my system ) of the Ogg file you wanted to change.

[Neo Neko]

You will have to convert the audio from vorbis to PCM or MP3 and then send it in the AVI muxer with the video. You can do all that in graphedit. Just use Tobias's filters to convert the Vorbis stream to PCM and then chain in your favorite working MP3 compressor. Finally conect it to the AVI muxer and go.

[Mikele]

So there is definitely no way to have an AVI with Vorbis sound? And it's also impossible to demux a Vorbis stream from an OGM without decompressing it? Oh my... Then why OGM is supposed to be better than AVI? If all these problems are due to an alpha or beta stage or the lack of a good editing software, then that's fine, but if they're not then I hope that a format with so much limitations doesn't become too popular.

[slavickas]

Originally posted by Mikele
So there is definitely no way to have an AVI with Vorbis sound?


u must compress with vorbisACM ( or add with nandub ?)

And it's also impossible to demux a Vorbis stream from an OGM without decompressing it?

possible but only to ogg format or other which supports vbr audio
Oh my... Then why OGM is supposed to be better than AVI?

bucause we can use vorbis in it

[Neo Neko]

Originally posted by slavickas
u must compress with vorbisACM ( or add with nandub ?)


The Vorbis ACM encoded audio will not keep synch. Vorbis muxed with Nandub into an AVI will not work if you seek.

Originally posted by slavickas
possible but only to ogg format or other which supports vbr audio


Marty over at vidomi.com has wipped up some AVI extensions that might make it possible. Problem is thay only his software is capable of creating or properly playing it. The info on what he has done is open though so someone else can impliment it.

Originally posted by slavickas
bucause we can use vorbis in it

Vorbis is a good reason, but there are others as well. OGG when dammaged will still play fine. If your AVI is dammaged it is almost useless. You will have to use a program to remove the errors and lost data and write the recoverd file to a new place. So for sharring or long term archival OGG is a double boon. You can play incomplete files and your files are more resistant to dammage. Past that the format is very open and flexible.

[Mikele]

OGM has some nice features, but I think it's too early to leave AVI behind. AVI is old and needs to be tweaked to handle some new stuff... but it works perfectly. OGM's DS filters are still beta, the format is still uneditable and many rippers have already switched to OGM which I think is a rather risky decision.

And I don't like Vorbis at all... a 64kbps Vorbis sounds really bad, so in order to achieve the same sound quality as MP3 128 ABR you have to go ~96 kbps, which is not such a great advantage. And about its multi-channel capabilities... I'd prefer to mux the *original* AC3 5.1 sound to a 2 CD AVI.

Of course I like its open-source and free-patent nature. But I don't like incompatible formats :( XviD is a good example of choosing the right path. It's great, it's better than Divx, it's free, it's open source and it works.

Just my 2 cents.

[Neo Neko]

Originally posted by Mikele
OGM has some nice features, but I think it's too early to leave AVI behind. AVI is old and needs to be tweaked to handle some new stuff... but it works perfectly.

OGM's DS filters are still beta, the format is still uneditable and many rippers have already switched to OGM which I think is a rather risky decision.


I agree with you in part here. We are not yet ready to abandon AVI entirely. But the OGG directshow filters work quite well ATM for almost everything. The main problem some have been having is with Divx5 and the just released subtitle filters. Generally I use OGG when I need a video encoded but don't plan to edit it again. Something like a whole movie. Other than that I still use AVI for all my finised video captures and similar stuff.

Originally posted by Mikele
And I don't like Vorbis at all... a 64kbps Vorbis sounds really bad, so in order to achieve the same sound quality as MP3 128 ABR you have to go ~96 kbps, which is not such a great advantage. And about its multi-channel capabilities... I'd prefer to mux the *original* AC3 5.1 sound to a 2 CD AVI.


Vorbis is not optimised for bitrates much below 80kbps ATM. But at 64Kbps is will still run circles around WMA at 64Kbps. Once RC4 is finished we should see much improved 64Kbps performace. Though for my movie rips I doubt I will go much below 80Kbps if at all. If you prefer to use AC3 you should still be able to have it in the OGG just like the AVI. The file is layed out differently but the same codecs are involved and used. Also we might be able to see AAC come into play for OGG as well some time soon.

Originally posted by Mikele
Of course I like its open-source and free-patent nature. But I don't like incompatible formats :( XviD is a good example of choosing the right path. It's great, it's better than Divx, it's free, it's open source and it works.

Just my 2 cents.

OGG should not be an incompatable format. Anyone is free to use it so long as they stick to the specs. It is just that things like Xvid have seen much more attention by many more coders than OGG has yet. So far xiph.org has got OGG prety well fleshed out. But Tobias is the only coder as of yet who has taken this direction and begun development of it for these purposes. Ingo Rafblum was and still is working on directshow filters to put Vorbis inside AVI I believe. But these two guys so far have worked very much alone on their respective projects. Though they have been in contact about common points of intrest, the general OGG specs, and compatability between their two pieces of software. But ulitlmatly at this point they are a couple of one man coding machines. :sly:

[TobiasWaldvogel]

You can't edit the fourcc code directly in the stream because there are CRC checksums which must be recalculated in this case.

I thought already in including a kind of FOURCC translation table in in the Ogg Splitter to give the choice between the XVID and DIVX decoder. I think this is even the better choice. What do you think?

Anyway the easiest way right now to change the FOURCC is following:

Create a graph (but connect only the video!!!)

File source -> Splitter -> AVI Muxer -> File Writer

Now you change the FOURCC in the AVI

Now create a second graph: (Video from the AVI and sound from the original Ogg file)

File source AVI file -> AVI Splitter -> Og Multiplexer - Writer
File source Ogg file -> Ogg Splitter /

Best regards,
Tobias

[Mikele]

Muy buenas Tobías, no sabía que eras de España :)

Originally posted by TobiasWaldvogel
You can't edit the fourcc code directly in the stream because there are CRC checksums which must be recalculated in this case.It looks like OGM is too perfect, good and old AVI doesn't mind if you change some bytes :)

I thought already in including a kind of FOURCC translation table in in the Ogg Splitter to give the choice between the XVID and DIVX decoder. I think this is even the better choice. What do you think?Yes, I think it will do. And if that setting is saved in the splitter settings, it would be active for every OGM you play in the future. It would be like doing a massive change to all the files without even touching them. And it could also work with files on a read-only media. Sounds good!

[Neo Neko]

Yes I second that idea.

[philippas]

An idea
Open your file in graphEdit and remove the divx decoder and insert xvid's decoder in its place.
Save the graph file as grf and the rename it to avi or whatever extension you want and associate it with a player.
If you can link in the graph the video(pin1) with the xvid decoder it should play fine via the pseudo file you created.

EDIT:I've tried the above but it doesn't work. I guess the xvid decoder checks for the FourCC and if it's not xvid it doesn't connect the pins. Maybe nick could modify it's filter so that it allows to accept the divx fourCC.

[tfh69]

Well I have a problem that is related.

I have done a ogm file with

1 Xvid Video Stream
1 Ogg Audio Stream
1 Subtitle .srt stream

All this renamed to .avi

Well I wanted to change the FourCC of the video file so dumb me used Noc Avi FourCC changer ON the ogg media file directly (should never have renamed it to avi ) and now , my file is considered by most players , and sadly Graphedit as just a Xvid file .
Thus when i open it up in Graphedit , there is only one output pin :(
For the Video .
And of course no sound or subs when playing it in any player .
( ANd i know the sub and the sound is still somewhere in the file because the filesize hasn't changed )

So my question Is there a way to change the avi file's FourCC to OGG or OGM i don't kno wwhat it is supposed to be for ogm .
( So that my comp sees it as a ogm file and not a plain Xvid video )

Or a way to exctract the audio from the file so i can redo an ogm file ?

tfh

[Neo Neko]

There is no fourCC for OGG. OGG is a container format like AVI and therefore has things similar to fourCC codes inside it, but it has no fourCC code itself.

At this point if you renamed it to AVI and used an AVI fourCC changer then your OGG is messed up and unfortunatly unrecoverable for the most part. You would have to know what data was overwritten when it inserted the fourcc code and replace it.

I like OGG for both audio and video, but my thoughts on it are this. Pick a player for your OGG media. If you have more audio OGG then choose an audio player. If you have more video OGG choose a video player. It is not worth it and will only cause problems to rename the file to *.OGM or *.AVI. You do not alter the extension of an AVI file based on it's contents. AVM = video, AVA = audio? Why do it with OGG? OGG and AVI are very analogous. OGG is just a more moddern, more capable format.

[tfh69]

Well Neo Neko ,
thanks for your answer , i sort of knew that i totaly messed it up but i hoped that maybe some genius in here had an idea .


Well guess i'm back to ripping the dvd again .


Thanks anyway .

[philippas]

@ tfh69

Open again the file with the FourCC changer and change the FourCC from XVID to "...."(four dots). I've checked two seperate clips with a Hex editor and when you change the FourCC you overwrite four dots at the address B0. Look at the picture below:

[Neo Neko]

Good man! Beat me to it! Damn working on a weekend! I hates it!

[philippas]

Sorry the above example was from samples without audio. If the ogg has audio and video you have to change at address 70:XVIDdio to
70: E.audio and then it will work fine.

[philippas]

A correction again i don't know why the above doesn't work.
If you open another ogg(renamed avi)file with the FourCC changer copy the FourCC that gives you and paste it to your file, it will then work.
The problem is that the dot in E.audio string has to be changed into the character "
"

EDIT: Thus open the file with the FourCC changer and replace the XVID FourCC with E
au.

[TobiasWaldvogel]

Originally posted by Mikele
Muy buenas Tobías, no sabía que eras de España :)

La verdad es que vivo en Madrid ya hace dos años pero soy de Alemania. De todas maneras estoy bastante bien aqui ya controlo mas o menos el idioma :)

Well, concerning the fourcc topic:

Inside the streams I store the codec identifier in form of the four character code and the new version comes with a fourcc mapping feature (release planned for tommorow 19.03). If you like to use xvid for playback you just have to enter a mapping DIVX -> XVID

By the the way if you use my Ogg Cutter utility (release planned tomorrow) you can just save a copy of the whole movie which results in remultiplexing the whole file (and adapting the fourcc change from the mapping :) )

So you just to be patient one more day

Best regards,
Tobias

[philippas]

So you just to be patient one more day
hahaha :D I'm very impatient ! Can't wait for the release tomorrow.

[tfh69]

Thanks Philipas ,

I used Nic's FourCC Mini avi changer ( comes with Koepi's Xvid i think ) thus i changeed TWO values in my ogg file )
What is labeled

FourCC Description Code
FourCC Used Codec

When i change both values to the one you gave me : E
au
I can now play the ogm file ( better than an error :) ) BUT no sound and when i open it in graphedit Still shows just a Video out pin .

So how cna i tell what was the second value changed ?

( btw i tried opening another ogm file and pasting it into this one , it didn't work :( )

Or maybe you know which is the other value overwritten ?


Thank you .

[TobiasWaldvogel]

My new Ogg Cutter os now available on http://tobias.everwicked.com Please note that you have to upgrade the OggDS to latest release.

Well, if you want to change the fourcc

- goto the properties of the splitter and enter a mapping
e.g. DIVX -> XVID
- Now the OggSplitter reports the new type and DS will use the XVID decoder
- If you want to change definitly in the file take the Ogg Cutter, open the file and save it, without changing start and stop.

Tobias

[Mikele]

Vobsub now works perfectly and the FourCC mapping is really powerful. Great job, Tobias, and thank you!

EDIT: The cutter works great, but how can you know the final size of each piece? I couldn't find a way to find the closest keyframe to a 700 mb position, for example.

[Ripe73]

HI!

Thanks for the Oggcut:) i did a test and cut a movie, the first part work fine splitted with subtitle but the second part the subtitle was gone after 7 min in the movie thats strange.

Anyone know how to cut the movie in 2* 700MB exactly?

and do i really need to cut in a keyframe when the movie is in a container?


EDIT:Sorry about this report the subbtitle was corrupt everything work fine thanks for a great format;)

Thanks

[philippas]

@tfh69
With Nic's avic change the first box to "E
au" and the second leave it empty(delete the xvid in your case).
Tell me if it works :)

@TobiasWaldvogel Great work !!!