Is MXF a type of MPEG2 too ?

[plainman007]

Is mxf based on the mpeg 2 format ? Or is it an MPEG 4 format ?

[David Jimerson]

MXF is only a wrapper. What's inside it could be anything.

[Barry_Green]

MXF is a file format, like AVI or Quicktime. As David said, the contents could be anything. Sony uses its proprietary implementation of MXF to wrap its XDCAM-HD files, and yes those are MPEG-2 files.

[plainman007]

Whys MXF called an interop format ? whats interop in a basic way ?

[David Jimerson]

It's supposed to be universal, so that it can be used with anything. Sony, of course, doesn't like actual universality.

[plainman007]

OK. Final doubt. Is MXF a format that orinates a from a camera or is an intermediatary format which is used in the post production pipeline or a distribution format. Or is it a combo of these ? Why MXF ? Also ive read that Raylight enables one to drag an MXF directly onto the vegas timeline ? So which means MXF is a originating format from Sony cameras ? Confused here, would be glad if you could throw some light. Pardon the pun.

[David Jimerson]

It's just a wrapper -- it's a format that every system is supposed to be able to use. It wouldn't be used for distribution, I wouldn't think. No real need.

[plainman007]

And MXF is a file format resulting from XD Cam ? Just like the m2t from a HDV cam ?

If every system can use it then why are they pedalling raylight to enable one to use MXF on the vegas timeline. Ive dragged a MXF (ofcourse i rendered it from vegas itself since i didnt have any mxf files to start with) and the mxf loaded fine onto the vegas timeline. I could cut etc. Then whats Raylight support needed for ?

[Barry_Green]

MXF was designed to be one unifying all-inclusive interchangeable file format. It can originate from camcorders, it can be originated by NLEs, it can be archived by archive systems... basically if everyone implemented it, we'd have universal file interchange across all systems.

The video production world is transitioning from tape-based to file-based. MXF is intended to be that one single unifying file format.

[Barry_Green]

And MXF is a file format resulting from XD Cam ?
XDCAM-HD produces MXF files, but they're incompatible with the MXF files that everyone else uses. Sony produced their own version of MXF, called MXF Op-1A whereas everyone else is using MXF Op-Atom.


Just like the m2t from a HDV cam ?
HDV cameras don't produce files, they produce tapes. The tapes get ingested into a computer by an NLE, and it is the computer NLE that creates the "m2t" file. If you ingest the footage into a Mac/FCP system it won't make an m2t file, it makes a .mov file.

Thomson/Grass Valley, Ikegami, and Panasonic camcorders all produce MXF Op-Atom files. Sony XDCAM HD makes MXF Op-1A files. Then for their new XDCAM EX system they switched to making .MP4 files.


If every system can use it then why are they peddalling raylight to enable one to use MXF on the vegas timeline.
Because Vegas is a Sony product, and as a Sony product it only supports the Sony-proprietary format of MXF. Only Sony uses Op-1A; if you want to use any other type of MXF file in Vegas you'd have to get something like Raylight to allow more universal MXF support.

[plainman007]

Thanks Barry. Very informative. But also very paradoxical that MXF was intended to become a universally cross-compatible standard and then sony had to stick their indifferent noses in to ensure that there was an incompatibility there too. They could have stuck to the atom format too unless their mxf formula is in someway superior to the former. The HVX too generates mxf files from its p2 cards ? About HDV i know its a tape format using the same pitch speed as dv25 to record mpeg2 compressed data onto a normal dv tape @ 25Mbps. Im also aware that this digital data is read by the NLE which in turn makes it into a m2t file. I just wanted to know if MXF was similar to m2t. I thought its an MPEG2 which gets recognized and saved as MXF on disk. I think even .m2t is exclusive to sony right. If FCP captured HDV from a sony (i dont even know if thats possible) it is saved as a mov ? Thats news to me. I thought FCP wouldnt even recognize the Z1 HDV cam.

[Barry_Green]

Thanks Barry. Very informative. But also very paradoxical that MXF was intended to become a universally cross-compatible standard and then sony had to stick their indifferent noses in to ensure that there was an incompatibility there too.
Paradoxical? Typical, is more like it. They've always done this, they've always insisted on having proprietary formats. The good news is that they're shutting down their ATRAC music store and embracing MP3 like everyone else in the known universe, so maybe there's hope. :)


The HVX too generates mxf files from its p2 cards ?
Yes.

is read by the NLE which in turn makes it into a m2t file.
Maybe. The NLE could turn it into a Quicktime file. It could turn it into an .AVI file if they wanted to. The point is, it's digital data and the NLE can do whatever it wants to that data and store it in whatever file type it wants.

That's not the same as with the camcorders from Panasonic, Thomson, Ikegami, et al. They actually create the digital files themselves; it's not up to the NLE to decide what type of file format will be used.

With HDV, the NLE can make it whatever kind of file it wants to. PC editors typically make .m2t files, the Mac doesn't. The Mac makes 'em Quicktime files.


I just wanted to know if MXF was similar to m2t.
In no way, shape, or form is MXF similar to m2t.


I thought its an MPEG2 which gets recognized and saved as MXF on disk.
No -- it has nothing to do with MPEG_2. The MXF file contents *could* be MPEG-2, or they could be MPEG-4, or they could be DV or DVCPRO or DVCPRO50 or DVCPRO-HD, or they could be Avid DNxHD or basically anything.


I think even .m2t is exclusive to sony right.
Definitely not.


If FCP captured HDV from a sony (i dont even know if thats possible) it is saved as a mov ? Thats news to me. I thought FCP wouldnt even recognize the Z1 HDV cam.
Yes FCP recognizes HDV, and yes it saves it as Quicktime movies.

[edweibe]

So is an MXF a considered a wrapper, or is it a stream? If its a wrapper, what formats is it wrapping? I see .bmp files in the P2 structre quite easy to recover. I am experiementing with some recovery techniques but am I recovering just an mp4 stream or what?

[Barry_Green]

You should probably head over to SMPTE and look up the specs for MXF Op-Atom.

[plainman007]

Barry > does m2t refer to Mpeg - 2 - Transport Stream ?

Also in vegas there are options for creating Mpeg2 Transport / Program Streams. Whats the difference between them ?