Ogg audio in divx movies

[Erci]

I'm beginning to play around with ogg audio in DivX movies. I only have one problem. When I want to calculate how shall I calculate the frame overhead for the ogg audio. I've heard it's not the same as in MP3 sound but I have no clue how to do. The way I do it with MP3 is to use a GordianKnot or Nandub.

I also have another problem and that is. I can't convert MPEG files with nandub. Every time when I've done the first pass and it starts on the second pass it's error screen apears. Though I have no problem att all converting the same MPEG file with VirtualDub.

Does anyone know anything about this?

//Erci

[xviddivxoggmp3]

ogg and mpeg

if you tweak the ogg you can get better quality then an mp3 at 2/3 of the size.
as for virtual dub and nandub i believe each has support for particular files. i would check to make sure you have all the updates just incase you missed a valuable dl
sorry i couldn't be of more help.

[khp]

Bitrate calculation with Ogg files

Here is what I have been doing...

First convert AC3 to ogg, that way we know the exact size of the ogg ogg audio stream.

Then in GKnot load the ogg filesize into the Audio A box by using the select button, or just enter the filesize manually.

Then set the AVI-frame overhead to 1*vbr mp3, this should be resonably close. I have only done one proper test, so far, so I could be wrong.

Checkout this thread, about my other ogg related tests.

EDIT: 1 small modifycation, it looks like I set gordianKnot to calculate the overhead of 1*ac3 instead of 1* vbr mp3. That makes a difference of about 2 MB

[Erci]

I thought about doing that way. Choose the ogg file in GK I mean. But I heard that this should give you about 4-5 mb of the real frame overhead size. But I'll try, and I believe I have to try to do a mode2 cd to since it'll give you alot better quality on the movie.

//Erci

[khp]

Yes, an extra 100MB for free, is just too good to pass up.

[Erci]

Yeah only one big problem for me!

My nice little friends are going to have a problem with it=)
They love my nice little DVDrips and also like to copy them alot=) a little bit harder for them=) but actually that's not myu problem=)

//Erci

[Enchanter]

I recently read on the ogg format and am interested in learning more about it. There are a few things I need to ask to those of you who have played around with it.

I read in the FAQ on which players support the ogg format. However, the most of them are simply audio players, not the multimedia players that we all use and love. Thus, one question springs to mind. If I were to encode a video in the usual manner and mux it with an .ogg audio, will viewers, who have no idea what ogg is, be able to automatically play the movie? I know Winamp supports ogg, but does its installation alone enable WMP, for example, to play ogg files?

I'm still reading more on ogg currently and am trying to convert a .wav file to .ogg. I'll see how it goes. Cheers!

Edit: This thread pretty much answered it.

[khp]

I have been doing some precision testing...

Target file size 819200 KB

Audio size = 86404 KB
Subtitle files = 4262 KB
Avi frame overhead without audio, calculated in GK = 3421 KB

This brings the desired size of the video stream to 726738 KB

Actual size of avi file, produced with nandub, 729880

Assuming that GKnot is correct in it's calculation of the frame overhead, this would bring the size of the video stream to 726459 KB.

Converting the avi file into an ogm without audio, results in a 734118 KB file, which means that the overhead is 7659 KB.

If I mux in the ogg audio file I get a filesize of 820522, this means that there is no added overhead when muxing the audio.

My framecount for this test was 142850, this means that the overhead per frame is about 54.9 bytes per frame.

GordianKnot calculated,
the Aviframe overhead + AC3 overhead to be 6734 KB, and
the Aviframe overhead + vbr MP3 overhead to be 9001 KB.

[Batman]

I know little if anything about Ogg.

1) Is Ogg an audio "container" format such as the avi format. Is Ogg vorbis is the special "compression" that results in the reduced file size, much like divx.

2) there are dvd rips with ogg. where and how can I install the audio codec

3) is there a significant advantage of using ogg over mp3. Most dvd rips contain mp3 audio.

Thanks in advance If you can refer me to any guides or websites that contain general information on ogg that would be great.

[khp]

Originally posted by Batman
I know little if anything about Ogg.

1) Is Ogg an audio "container" format such as the avi format.

Yes. The ogg or ogm container format can contain both audio and video streams.

Originally posted by Batman

Is Ogg vorbis is the special "compression" that results in the reduced file size, much like divx.

Vorbis is the audio compression format usually used in ogg files, but I think, mp3 or ac3 can also be used. The developers of ogg and vorbis are also thinking about developing a video compression format called Tarkin.

Originally posted by Batman

2) there are dvd rips with ogg. where and how can I install the audio codec

Getting the DirectShow filter will install the Ogg stream Splitter and vorbis decoder filter.

Originally posted by Batman

3) is there a significant advantage of using ogg over mp3. Most dvd rips contain mp3 audio.

Some people claim that vorbis produce better quality than mp3, but I'am not really an audio freak so I can't really tell.

Originally posted by Batman

Thanks in advance If you can refer me to any guides or websites that contain general information on ogg that would be great.

Official home http://www.xiph.org/

[Batman]

Once again, thanks for your help KHP. If the data on the website is correct, ogg vorbis is a serious contender to the popular mp3 audio format.

[khp]

Muxing mp3 into ogm files

I just muxed an 81796 KB vbr mp3 file, with my 729880 KB AVI file using Nandub, this produced a 817256 KB AVI file. I then converted this to an ogm, this produced a 817607 KB file.

[Erci]

How did you manage to get the ogm file bigger?

Everything I have done with ogg audio is getting smaller.

//Erci

[khp]

I admit it's kinda funny ...

If I mux a mp3 file directly into an ogm file, I do get a smaller file, but for some reason I can't get any audio, on playback that way.

I have tried playing the file in Graph edit, but I can't connect the audio stream, that comes out of the ogg splitter, to anything.

It doesn't matter if I use Oggmux or Grahpedit to preform the muxing.

If on the otherhand I mux the mp3 file, into the avi file using nandub, and then convert that to an ogm, I get the above mentioned filesizes and playback works.

[Enchanter]

I'm still slowly testing the RC-3 release of the ogg encoder. Preliminary testing is currently being done on a low-quality sound source (sound from a 70 or 80 show). The MP3 and Ogg files are created from the WAV file.

WAV file : 2,242,166,828 bytes
128 kbps MP3 : 186,848,256 bytes
Ogg File : 150,482,439 bytes

The 128kbps MP3 sounds perfectly alright (No obvious LQ sound asociated with low bitrates). The ogg file, however, sounds noticably low in quality (compared to the MP3) at this filesize. I will try reencoding it to a filesize near that of the MP3 and see if there is a difference in sound quality. It is disappointing to me, however, that this format promises to achieve the same quality at a smaller filesize, and yet it does not deliver in this case. Oh well, only time will tell when I do further testings on other sources. meanwhile, I may give the more widely supported WMA a try as well.