Interleave & Overhead

[DoC hEx]

Does anybody know where I can get the Interleave & Overhead, for AVI, OGM, and Matroska, with audio format like MP3 V/CBR, Ogg, AC3? Before I try to reverse-engineer other apps?

[mpucoder]

Can't speak for the other containers, but AVI has variable interleave (which you can control with VirtualDub).
In any case, no need to reverse engineer, the specs for all are easily available on the web.

[Movie Maniac®]

well, for avi files should be easy.

I've made a lot of reseaches all over the web, and found out that, for CBR audio tracks, you have to consider 24 bytes for every interleaved audio frame, (in the case of CBR MP3 or WAV). Of this 24 bytes, 8 bytes are devoted to the frame header and an additional 16 bytes for the index chunk entry.
In the case of VBR audio, the bytes should be 40.

In addition to this, for avi files you can consider also the video overhead, wich should be another 24 bytes per frame.

I really don't know the correct values for OGM nor Matroska, but I will be happy if you let me know them ;)

Bye

P.S. take a look at my calc if you need something to test yours (not that mine is perfect...)

[DoC hEx]

@Movie Maniac®

Thanks for the Info!

[ChristianHJW]

Ever been to our homepage yet ;) ?

http://matroska.sourceforge.net/overhead.html

About MCF ( not matroska ) and OGM, a useful link was always the old link from Ingo : http://cvs.sourceforge.net/cgi-bin/viewcvs.cgi/*checkout*/mcf/doc/container_comparison.html?content-type=text/html

You may dig around on the old MCF specs pages for more info : http://mcf.sourceforge.net/oldpage/ . Again, MCF overhead has nothing to do with actual matroska overhead, and the things posted there may not be valid for actual MCF files either, as their actual specs are now here : http://solidhardware.com/sn/mcf/mcfmain.htm ..... i was just giving this link as a hint where to search, as i may have overseen some things ...

[alexnoe]

It's more difficult with AVI; you have to distinguish standard AVI, Open-DML AVI and Open-DML + legacy AVI.

Concerning MP3 CBR, you get one overhead portion* for each chunk, which can be just 24ms, or, if you want, 5 seconds...


*: 24 bytes for standard AVI
16 bytes for open-dml AVI
32 bytes for the area of an open-dml + legacy AVI over which the legacy index is formed

[stax76]

are you sure you want support OGM, I don't think it's worth the effort, when your application is finished probably not many people if somebody at all will use OGM

[Movie Maniac®]

Originally posted by Dolemite
are you sure you want support OGM, I don't think it's worth the effort, when your application is finished probably not many people if somebody at all will use OGM

Excuse me

Can I ask you why?
What's wrong with OGM?

Bye

[Selur]

DVX is probably thinking matroska will be better then ogm once "DoC hEx"s application will be ready,..

Personally I don't think that matroska will replace ogm that fast, but we'll see. :)

Cu Selur

[DoC hEx]

@ChristianHJW

Thanks for the links they’ve been quite useful.

@Everybody

Personally I think it will take Matroska 2-3 months before its fully accepted as it still needs to be seen to work on a large scale outside the currently limited support, i.e. requires wider adoption in as many Apps as possible. It’s still relatively new, and not feature complete from my understanding, so that’s a negative.

I don’t see OGM being dropped for at least 6 months, as it is accepted and has a proven track record. It does matter if Matroska is better or not at the moment. OGM is proven, while Matroska is impressing by the day, but still only building up support.

And well, AVI is AVI enough said...

As for my App, it’s going to have AVI support on release with OGM and Matroska in Alpha mode for feedback. I’m hoping to have ‘Alpha 1 Public Preview’ in the week beginning the 26th of this month.

[stax76]

Personally I don't think that matroska will replace ogm that fast, but we'll see.


Afaik DivX and OGM never worked proper, maybe I did something wrong but I noticed always occasional jerks, many people complained about this in forums but I've never read about a solution. There are many active developers backing Matroska, If you read the rest of my posting you will probably hope they are more skilled than I. ;) I don't think it will take long until they implement and fix some left issues.


Ever been to our homepage yet?

http://matroska.sourceforge.net/overhead.html


very professional documentation. My problem is I have no clue what to do with all this clusters, blocks, laces, I and B-Frames etc. I'm not concerned about all this. How do I approximately do the calculation without knowing about clusters, blocks, laces, I and B-Frames etc. Maybe somebody could give some easy to understand examples for instance how do I calculate a 1 CD rip with 2 Vorbis streams, what about 2 CD's, AC3 etc.

[ChristianHJW]

Originally posted by Dolemite
very professional documentation. My problem is I have no clue what to do with all this clusters, blocks, laces, I and B-Frames etc. I'm not concerned about all this. How do I approximately do the calculation without knowing about clusters, blocks, laces, I and B-Frames etc. Maybe somebody could give some easy to understand examples for instance how do I calculate a 1 CD rip with 2 Vorbis streams, what about 2 CD's, AC3 etc ... yes, good idea mate, we might comeup with some rules of thumb to make things easier for you guys ... or you wait for the tool of the gentleman that was posting here originally ( he will maybe make it a DLL also ? ) ...