MCF, XCD ??? Confused

[raistlin2k]

Sorry guys, but I start getting confused about MCF & XCD!

What's the exact difference?

Now I have a lot of OGMs on my harddisk, just waiting for a working mode2-CD-system. Therefor i ask you: Will there be a muxer for MCF or XCD, so I don't have to use OGMs? See, OGM needs some bits for organization and MCF does, too! SO Why use one container (OGM) in another one?

Hope you can help me to see all this more clearly

Raist

[Doom9]

mcf is a container format.. like ogm..
xcd is a data storage format.. like iso9600 or udf.. you can put data in any container format onto a data storage medium using whatever data storate format you like (as long as you have applications supporting it).

[ChristianHJW]

OGM and MCF are competing formats, in a certain way. We believe both formats will have their advantanges, like OGM for streaming use and MCF for editing, but in the end you may be able to use one of both without having to think about that a lot, both will be real neat formats and hopefully be well and widely supported by many applications.

What comes to XCD, it is targeted to allow using CD space more effectively ( up to 800 MB on 80 mins CD ) and it will support a number of different formats like MCF, OGM, AVI, etc. . Depending on the formats individual error detection ( EDC ) it will be intelligent enough to know what data areas must get special protection and error correction ( ECC ) to make sure the file is playable even from a scratched disk. To do so XCD has to know a lot about each format, like where the sensitive data like headers etc. is, and the MCF team hopes they will have an advantage here by closely cooperating with XCD dev team, making MCF the first really supported format in XCD.

Hope this does clarify things a bit ...

[raistlin2k]

OK.

Till now, XCD (same as MCF-CD?) has no own muxing system, so I have to use Oggmuxer for creating an ogm and then use mode2cdmaker.

So I even get twice structure data, first 1.11% for OGM , then 0.54% again for mcf? Is this correct? Or are this 0,54% only related to MCF and not to XCD?

I also read that MCF will probably be the first perfectly working container system for XCD, well, will it be possible to mux and create the XCD-image in one step? Will this be possible? I saw that XCD was somehow a splitting group of MCF-CD team, so based on the same system a combined muxer and image-creator should be possible, hm?

Raist

[avih]

xcd will have no special muxing capabilities.
xcd is most easyly imaginable as SVCD with few enhancements:


XCD and SVCD similarities:
--------------------------
1. usage of mode2 form2 storage (less error correction --> larger user files)
2. menu system independent of the media files
3. fixed directory structure
4. fixed cd layout scheme (tracks, sectors etc.).

XCD 'enhanced' features:
------------------------
1. any media type (while SVCD can hold only mpeg2 system streams).
2. allowing storage of mode2 form1 media files (for formats without error resiliance), or 'mixed' form 2 and form 1 streams to allow only partial error correction for the media files that can handle errors to some extent (the last method will probably the most common).
3. directory for arbitrary files (like filters, players, etc.)
4. playlists
5. maybe bootable (i.e. boot on x86 from the cd, for playback without depending on the OS or installed applications)
6. player support in 'levels'. i.e. a player is level 1 if it can only play and seek single stream at a time (the dshow filter will enable any windows media player to be XCD Level 1 player). a level 2 player will also support playlists, and level 3 player will also support menus. (svcd has a 'fixed' level, therefore a player that can't handle svcd menus is not considered 'SVCD Compilant').
7. did i forget anything?? ;)

so XCD doesn't 'care' about the container format itself (i.e. whether it's ogg, mcf, avi or mpeg), it just defines a method of putting media files on the cd, while allowing to use more of the cd space and adding few 'external' features like playlists, menus and arbitrary files.

it's true though that in order use mode2 form 2 files, we need to have good knoledge about the container format, and the parts of the files that are crutial for the stream to be playable. since we know the mcf team well, it's logical that mcf will be among the 1st to utilize the full potential of xcd, however, you will still be able to put 'unknown' containers as mode2 form 1 (similar to 'normal' cd storage) and enjoy the benifits of XCD (but without the enhanced capacity). naturally, we're looking for information about other containers as well (like ogg), such that as much containers as possible will be able to enjoy enhanced capacity on XCD.

cheers
avi.

[raistlin2k]

Thanks alot, avih, now I see it clearly.

So I will wait until ogm gets perfectly supported by XCD (enhanced features, as you say) or see how MCF is improving?

BTW, are there any MCF tools out there, besides mcf-cd-maker, which is in fact not really mcf-related but mcf-cd / XCD!

[avih]

currently (afaik) there are no mcf tools, but there should be soon (if i understood the mcf developers posts correctly).

there's also no XCD yet, as we're working on the specifications now.

the the mode2cdmaker tool and filter (formerly named mcf-cd by mistake) were a proof of concept that it's possible to store 800M files on a 80Mins cd (using the mode2cdmaker tool) and read them on the fly (using the filter). the work done on these tools is important since it teached us about cd storage and dshow filters. XCD will probably use the 'technologies' tested in these tools, but will (hopefully) offer all the other features mentioned in my previous post, most importantly: the error protection methods that are missing in the mode2cdmaker tools.

in the meantime, i suggest that u continue to work exactly as before (while 'forgetting' about XCD and MCF). just wait, and hope it'll be ready soon.

cheers.
avi.