MKV? MP4? What?

[Octo-puss]

What's the difference? I always though Okay, so there are videos in .avi and in .mpg/.mpeg. Later I came to the conclusion it's not that simple, but I still don't understand anything of this :)
All I heard was that both these are "containers", whatever that means. Can someone enlighten me or link me to an explanation?

[Ranguvar]

AVI, MPG, MKV, OGM, VOB, ASF (often WMV), etc. are containers. That means they are file formats that "contain" video and audio streams (possibly subtitles and more). The types of video/audio/subtitle steams they can contain differ. For example, let's say MPEG-4 ASP. Contrary to popular belief, an AVI container cannot contain "Xvid video" or "DivX video". DivX and Xvid are codecs, in other words, packages of an encoder and decoder for a specific format. Both Xvid and DivX are encoder/decoders for MPEG-4 ASP video.

[Dark Shikari]

From one of the FAQ threads:

"A container format allows you to combine different multimedia streams (most of the time audio and video) into one single file."

[Blue_MiSfit]

Think of russian Matroska dolls - you know the little dolls that pop open, and have more dolls inside?

No small coincidence that the Matroska (MKV) container is named as such :D

If you're moving "things" from point A to point B, you want to do it all at once, so you put them in a "box".

The "things" are the streams - video, audio, and subtitles. The "box" is the container.

Different boxes are better at storing different things :)

I hope our replies have helped!

Containers: AVI. MP4. MKV. MPG. WMV(asf). MOV. TS.

Video Formats: MPEG-4 ASP, MPEG-4 AVC, MPEG-1, MPEG-2, VC-1

Video Encoders (corresponding with above formats): Xvid, x264, TMPGEnc, CCE, Microsoft Expression,

Containers hold Streams defined by Formats produced by Encoders

:)

~MiSfit

[unskinnyboy]

A related thread: http://forum.doom9.org/showthread.php?t=137498

[Octo-puss]

Contrary to popular belief, an AVI container cannot contain "Xvid video" or "DivX video". DivX and Xvid are codecs, in other words, packages of an encoder and decoder for a specific format. Both Xvid and DivX are encoder/decoders for MPEG-4 ASP video.

How comes most movies in divx/xvid come in .avi files then?

[unskinnyboy]

How comes most movies in divx/xvid come in .avi files then?Because most people put DivX/Xvid videos in AVI container, for the sake of standalone player support. For the other containers like MKV, MP4, OGM etc, which are capable of containing DivX/Xvid, standalone support is pretty much nil.

[numaios]

Contrary to popular belief, an AVI container cannot contain "Xvid video" or "DivX video".
How comes most movies in divx/xvid come in .avi files then?

What Ranguvar tries to tell you is those movies you talk about don't actually contain DivX video or Xvid video: they contain MPEG-4 ASP video which has been encoded using DivX or Xvid codecs (it's a matter of terminology).

Most movies come in .avi files because AVI is the most widespread container, and maybe because standalone players can't handle other containers.

But AVI can't have subtitles in it. Even there is a MPEG-4 ASP video feature called B-frames which is not fully supported.

[Blue_MiSfit]

Not true. AVI can have subtitles.

~MiSfit

[unskinnyboy]

But AVI can't have subtitles in it.AVI sure can have subtitles, but standalone support for it may not be there.
Even there is a MPEG-4 ASP video feature called B-frames which is not fully supported.I highly doubt there's even one decent MPEG-4 player in the market now, which can't support encodes with 1 B-frame. Standalone support only becomes iffy as the number increase (> 2).

Octo-puss, If you could search and read, there are tons of threads about this subject.

[numaios]

Not true. AVI can have subtitles.Really? In which format? It must be some sort of hackery. The same applies to B-frames in AVI.

I highly doubt there's even one decent MPEG-4 player in the market now.
I wasn't talking about playing avi/B-frames in a standalone player, that doesn't mean that avi specs REALLY support B-frames. It had to be hacked for that being possible. unskinnyboy, I was referring to this post called MPEG-4 B-frames in AVI/VFW hackery description.

http://forum.doom9.org/showthread.php?s=&threadid=80430

The statement is: the "video for windows" (VFW) codec interface (as used in virtualdub(mod)) and its container (AVI) can NOT handle b-frames, and they will never even know that this frame type exists!

[unskinnyboy]

AVI supports text subtitles (srt and ssa) and it's no hackery. And yes, I know about the b-frame/VfW issue, but I was answering Octo-puss specifically on why there are so many DivX/Xvid files available in AVI. And the answer is - standalone support. And as long as the number of b-frames aren't above 2, almost all newer standalones would support b-frames in AVI with ease, hack or no hack.

[numaios]

AVI supports text subtitles (srt and ssa) and it's no hackery.
:thanks: for the info (I had no idea, really). Which muxing tool can I use to mux srt or ssa in an AVI file?

but I was answering Octo-puss specifically on why there are so many DivX/Xvid files available in AVI.Again, when Octo-puss asked "How comes most movies in divx/xvid come in .avi files?" he wasn't asking why there are so many DivX/Xvid files available in AVI. He misunderstood Ranguvar's statement: an AVI container cannot contain "Xvid video" or "DivX video". If you had read what Octo-puss wrapped in Quote tags, you would have noticed that.

almost all newer standalones would support b-frames in AVI with ease, hack or no hack.I agree with you, but that's a matter different from format limitations, and that's what I was talking about when I said B-frames are not fully supported in AVI.

[unskinnyboy]

:thanks: for the info (I had no idea, really). Which muxing tool can I use to mux srt or ssa in an AVI file?
AVI-Mux GUI (http://www.alexander-noe.com/video/amg/)
Again, when Octo-puss asked "How comes most movies in divx/xvid come in .avi files?" he wasn't asking why there are so many DivX/Xvid files available in AVI. He misunderstood Ranguvar's statement: an AVI container cannot contain "Xvid video" or "DivX video". If you had read what Octo-puss wrapped in Quote tags, you would have noticed that.OK, I see what you mean now. It's just a matter of semantics though - I see no issues in saying that we can put Xvid video or DivX video in AVI.

[numaios]

Thank you! I'll give it a try.

Please correct me if I'm wrong: the fact that a standalone player supports srt files burned with an avi doesn't mean that also supports srt muxed into an avi, right?

[unskinnyboy]

Please correct me if I'm wrong: the fact that a standalone player supports srt files burned with an avi doesn't mean that also supports srt muxed into an avi, right?Standalones usually support srt subs if they are with the same name as the avi and kept in the same folder. Is this what you meant by burned with? If srt subs are muxed into the AVI container, chances are very little that any standalone would support it. This is what I meant earlier when I said:

AVI sure can have subtitles, but standalone support for it may not be there.

[Blue_MiSfit]

Right :)

"burned in" usually means overlaid on top of the video and encoded as such.

"muxed in" means the SRT file as a stream inside the AVI - which AVIMux GUI can do, but standalone's probably can't handle.

Separate files seem to have more frequent support.

~MiSfit

[unskinnyboy]

"burned in" usually means overlaid on top of the video and encoded as such.There wouldn't have been any room for doubt, if numaios had said burned in. But, rather, he said burned with, which is a bit open to interpretation.

[numaios]

Standalones usually support srt subs if they are with the same name as the avi and kept in the same folder. Is this what you meant by burned with?
Yes, that's right! I meant burned in a cd or dvd with the srt subs, at the same place (and with the same name). Maybe I got into a muddle with prepositions (hope that's a valid expression :confused:)

"burned in" usually means overlaid on top of the video and encoded as such.
I thought that was called "hard subtitling", that's why I thought burn with wouldn't prompt confusion, but I will remember that other meaning.

Separate files seem to have more frequent support.
If srt subs are muxed into the AVI container, chances are very little that any standalone would support it. This is what I meant earlier when I said: AVI sure can have subtitles, but standalone support for it may not be there.
OK! Thank you, guys! Unskinnyboy, I wasn't totally sure if you were referring to SRT format (in general) or muxed SRT's (in particular) in that sentence, thanks for clearing my doubt!