DivX fills in the gaps and adds MKV support to Windows 7
by Ben Drawbaugh 
posted May 1st 2009 at 11:47AM
Windows 7 comes with many new under the hood enhancements that address some sore spots for Media Center fans, but we don't think any hurt as much as the lack of native codec support. The most popular file format online today is without a doubt MKV, but many don't understand that it isn't a codec at all, but instead a container. In fact it's a container that can hold just about any combination of video and audio, but most notably H.264 video and AC3 audio. Now the kicker in Windows 7 is that although it natively supports H.264 and AC3, it still can't play MKV files. Up until now enthusiasts have been installing the Haali splitter on the Windows 7 Beta, which has kinda worked. We say kinda, because for whatever reason the Haali Media Splitter exposes the H.264 stream in an MKV file as AVC1 and not H.264. What this means is that Windows doesn't realize it can decode the content natively and when you try to play one of these files on an Extender -- for example -- the video is unnecessarily transcoded. So now that you understand the problem, it appears DivX has the solution. The latest DivX Tech Preview features a Media Foundation -- the replacement for DirectShow in 7 -- component that will demux MKV files and allow the video and audio streams to be decoded with native Windows 7 codecs. Well, that's the theory anyways, we'll be following the comments closely to see how this turns out in practice.
Reader Comments (Page 1 of 1)
David S @ May 1st 2009 12:08PM
The secondary audio track limitation is big. I'm also guessing no subtitle support.
But still, this is huge.
Also, what about m2ts files that aren't h.264/ac3... like vc1/ac3 or h.264/dts. Maybe DiVX or another group can make a media foundation filter that allows for these files to be played by MS programs.
What's to stop ffdshow from going media foundation then?
Wolfgame @ May 1st 2009 12:39PM
Why stop development from happening? If the ffdshow-tryouts guys decide to go Media Foundation, then more power to 'em. Although I'm running the RC right now, and I haven't installed a single codec (did install Haali, however). I watch all of my movies in M2TS containers or DVD Folders for the most part. And I have MKVs associated with Media Player Classic HomeCinerma. Haven't had to install a single codec or filter yet.
Clayton @ May 1st 2009 12:42PM
but those of us with extenders........ what about us? :)
Hearsay @ May 1st 2009 12:34PM
Wow that post was so full of techno speak that I think only a select few will understand. I did but how many others will.
Clayton @ May 1st 2009 12:37PM
ME!!
This is good news!!!
youdiejoe @ May 1st 2009 12:43PM
It works! I was able to watch any MKV file from my Windows 7 box on my XBOX 360 with AC3 support! Huge, indeed.
Clayton Olley @ May 1st 2009 12:48PM
through media center extender interface or the xbox 360 dashboard?
Alton @ May 1st 2009 1:35PM
Does this fix the play/pause bug?
Randy @ May 1st 2009 1:50PM
Clayton: Through the Media Extender interface
Alton: don't know, was unaware of play/pause bug
Alton @ May 1st 2009 2:01PM
Typically when you play a HD MP4 files on Windows 7 Extenders once you pause it you can not hit play to resume the video.
youdiejoe @ May 1st 2009 11:34PM
took time to check this out and no problems with pause/play works fine
riverside_guy @ May 1st 2009 1:49PM
Why do we need ANOTHER container format? We've already got avi and mov...
Ben @ May 1st 2009 1:50PM
My understanding is that neither support AC3 and subtitles, which is why people choose MKV.
Mark @ May 1st 2009 2:17PM
Sorry Ben, but at least MOV does both. I would disagree with the article author's assertion that MKV is the "most popular file format online today". Unless you equate "online" with "torrents" that is.
http://en.wikipedia.org/wiki/Comparison_of_container_formats
Luther @ May 1st 2009 2:20PM
Looks like there's an ACM wrapper... might get support AC3/DTS via ACM codec.
Andrew Timson @ May 1st 2009 2:19PM
QuickTime containers both support subtitles and AC3, though I'm not sure if there's a QuickTime AC3 decoder outside of the one in an Apple TV.
AVI can happily support AC3 as well. Subtitles, less so; there's ways to get them in there that some clients recognize, but I believe that it's technically an invalid AVI file. (There are backwards-compatible documented AVI extensions, like the .DIVX format, that include subtitles and other features, though.)
However, while both can work, using MKV instead a) avoids Windows' poor QuickTime support; and b) doesn't get people confused when they can't play their H.264 AVI with AC3 audio, when their H.263/MP3 ones work just fine, because most people just look at the extension and not what's inside.
Raffi @ May 1st 2009 3:01PM
MKV is for anime nerds who need subtitles.
reuthermonkey1 @ May 1st 2009 4:38PM
.mp4 supports multiple audio streams, subtitles, etc...
I don't get why they use MKV when they could just use MP4...
Ethan @ May 1st 2009 5:30PM
Because 'the scene' is full of snobs.
Andrew Timson @ May 1st 2009 8:51PM
MKV supports a much wider range of video formats than .mp4 does.
xemumanic @ May 1st 2009 11:25PM
The thing I like about MKV is not only is it the ultimate container format, so it can hold any combination of video and audio codecs, but it has built in chapter support, WITH titles for said chapters, multiple audio AND subtitle tracks in one file, as well as the fonts for the subtitles if needed.
It is true the anime fansub scene uses MKV the most, but they've also always been at the bleeding edge of this sort of thing anyway. You don't have to be into anime to see the usefulness of these technologies.
xemumanic @ May 1st 2009 11:33PM
Argh, this is why we say this comments system is so broken. I realize I have more to say, but I gotta make a whole new post. Whatever, I'll deal.
Just a couple responses to whats been said. As for why not use .mp4 instead of .mkv, well mp4 implies AVC video and AAC audio. Hell, I don't even think I've ever seen an .mp4 with ac3 audio, but I'm sure someone can easily prove me wrong. Back to .mp4, YES, it supports subtitles, and YES, it supports multiple audio tracks, but most devices do NOT allow you to switch between them anyway.
Meanwhile, you can have a .mkv with a TrueHD audio track, or even a FLAC audio. I have one THD .mkv, and a few with FLAC audio.
Andrew Timson @ May 2nd 2009 10:18AM
@xemumanic But do those devices not letting you switch between multiple tracks in a .mp4/.m4v/whatever (same thing, different extensions) even play anything from an MKV file, much less support those features in them? I would expect that lack-of-features affects both formats.
Dummy00001 @ May 3rd 2009 3:08PM
@reuthermonkey1
MKV is much much simple. There were no full MP4 implementations until very recently. Even now there are only few commercial options - because of apparent feature bloat. (Hint: MP4 can do all what MP2 (DVD) could do and more.) That means that supporting full MP4 with all bells and whistles is relatively expensive and potentially taxing on hardware.
MKV does all what people want - subtitles, multiple audio channels, chapters - without need to resort to expensive commercial software.
MP4 is superior format, but it is too bloated and expensive. MKV is dead simple and cheap.
Engrudget @ May 1st 2009 5:04PM
Or for people who like to watch foreign films. I know, the nerve--how dare they watch anything that's not produced in Hollywood and has more than one language track.
James Enright @ Jun 12th 2009 2:18PM
MKV is not just for people who want to watch foreign movies.
What about the scene in "The Day the Earth Stood Still" starring Keanu Reeves. Which is a Hollywood movie.
About 52 minutes into the movie The Alien played by Mr. Reeves speaks Chinese to an older Chinese alien who has been living on earth for approximately 70 Years.
Without subtitles in this movie you just wouldn't understand what the hell was being said.
Unless:
a) You are also an alien who can speak Chinese. (Improbable this one)
b) You are of non Chinese descent who can speak Chinese.
c) You are actually Chinese.
d) you are a phonetic genius who can look up the translation in real time.
If none of these are true then you are totally screwed because what is said in that scene is fundamental to the story. And is not repeated anywhere else in the movie.
domerdel @ May 1st 2009 8:21PM
reuthermonkey1:
.mp4 only supports 2-channel audio.
Andrew Timson @ May 1st 2009 8:53PM
No, it supports multichannel audio. If it doesn't, then Apple's got some 'splainin' to do about their HD movies with 5.1...
ZeroK2 @ May 4th 2009 7:42AM
Andrew Timson - Apple hacked their M4V (which is basically MP4) container to support AC3 it does not do in a standardized manner so only Apple players will recognize it.
The MP4 specification was updated to support AC3 audio but very few players support the official spec. This is of course the problem with such containers and why MKV is better.
ZeroK2 @ May 4th 2009 7:38AM
It's simple why MKV
A) Is open source
B) Is a universal container so can hold any video/audio type
C) Has lots of features (subtitles, menus, attachments, chapters, multiple streams & more)
AVI/MOV/MP4/M2TS all have varying problems such as being proprietary, limited to selected codecs, missing features etc.
That is why MKV will replace this mess and as players even select Blu-ray players are adding MKV support.
As for the DivX preview I gave it a go and it works well enough though there are bugs of course, I was also able to play MKV videos on my Xbox 360 media center extender.
Ian @ May 4th 2009 4:28PM
MKV works fine on Win7 with the Haali splitter, using the in-box codecs complete with hardware acceleration. The only exception is when you need subtitles. Then you lose hardware support since vsfilter works in system memory
On the other hand "Native windows 7 cdoecs" has NOTHING to do with the 360 extender issue. It is a demux/splitter issue that the divix guys have fixed with their implementation.
The "whatever reason " MKV exposes H.264 as "AVC1" is that the content IS AVC1. The divx implementation is just masking that to enable compatibility with the 360 extender solution.
So now all three extender users can stream their MKV files without transcoding.
Ben @ May 4th 2009 4:32PM
Ian,
I'm not going to pretend I know the difference between AVC1 and H.264, but if the Windows native codecs can decode either, than why does it matter which sub type the splitter presents?
As far as I'm concerned DivX's implementation is a work around for a Microsoft bug, not the other way around. I think MS knows this and is just too far into the development cycle to address it. Luckily it seems it is easy enough for the splitter component developer to work around it.
I have three extenders myself, and I know three other people who use them, so it seems the last statement in your post is just as inaccurate as the rest of it.
peskypescado @ May 14th 2009 11:58AM
FYI, a new build of our Media Foundation MKV solution for Windows 7 today.
http://labs.divx.com/mkvwin7preview
Changes since initial Tech Preview:
* MKV thumbnails now work on Windows 7 RC1 (7100)
* Fixed disconnect from extenders after 30 minutes issue
* Now uses the Microsoft AAC decoder (now supports 5.1 AAC in WMC Extenders)
* Windows 7 RC1 (7100) is now required (will no longer install on older builds)
* Fixed file association issue when installed on 64-bit Windows 7
-- peskypescado, DivX Inc.
william @ Jun 29th 2009 12:02PM
I am able to play (SOME) mkv files streaming to the 360 with windows 7 RC1. That being said even using divx 7 I am unable to to stream mkv files with DTS audio to the 360 at this point, I am still working on different options. Media player 12 is able to play the DTS audio file with no problem on the same machine that I am streaming with once I installed Divx 7. One other thing, do you still have to split mkv files to (4Gig or less) with divx 7 when streaming to the 360. Thanks a great deal to anyone that knows these answers.