The VideoLAN Forums

I did a search here in several ways, nothing came back that was truly relevant.

I know VLC only supports WMV3 or HD video and WMA multi-channel audio through the Windows codecs. Further VLC appears to recognize the WMV extension (container) as ASF and that this support is about to change in favor of ffmpeg so that all users of other operating systems can enjoy WMV HD. We also hope that the issue of not being able to transcode/stream these file types and formats will become a thing of the past.

I'm writing this post because it appears that Microsoft has given us a twist in a new format for WMV and while it is still called WMV, it requires a new codec called WVC1DMO and is downloaded the first time you play this video type with WMP 10. It may be included with WMP 11, but I keep hearing that's buggy so am shying away from it at the moment.

At any rate, after downloading the codec WMP 10 plays the video fine on my machine in 720p resolution. My machine (P4 2.8GHz) is right on the verge of playing or not playing 1080p. Recently a change of video driver and the latest version of DirectX runtime has helped in this regard. While H.264 is still a problem in 1080p, WMV now runs better and MPEG is a bit smother both in a dshow player and in VLC.

So I tried to play several video clips using the new codec (WVC1DMO) in VLC (1080p) and to my surprise it ran smoother than it did in WMP that showed a few skiped frames or MPC that ran smooth video but had audio glitches while I found this strange as both use the same codecs I did put this off to my machine not quite being fast enough.

What I haven't mentioned here is that VLC 0.8.5-Final will not play these videos at all. There is sound but no picture. However, VLC 0.8.5 nightly dated 1/15/06 plays these almost flawlessly. I also tried 720p with the same result. While over all it ran smoother everywhere the same problem occurred with VLC 0.8.5-Final. So what I am suggesting here is that something has been lost along the way.

I am bring this up because:

1. You are about to make a change to VLC to support WMV through ffmpeg and you really should be sure it supports all of the variations of WMV so that the users will finally stop complaining about problems in this area.

2. Support for this format (WVC1DMO) has been lost in the current version.

Now before some one responds here with suggestions! Be it known that I can play WMV with WMA HD using VLC 0.8.5-Final, the basic DMO's work. Also I an NOT having problems with H.264 HD or MPEG HD using VLC 0.8.5 as long as I stay within the limits of my machine which is what I consider to be 720p for WMV, H.264 and MPEG 2. The new twist on this is I can now play the new WMV at 1080p in VLC but not in VLC 0.8.5-Final and I can play 1080p MPEG 2 under dshow but it is not as smooth using VLC.

I hope this is helpful to the devs and anyone having problems with WMV!

A response from a developer is requested!
Thank You!

http://download.microsoft.com/download/ ... vc1dmo.exe

The package includes:
wvc1dmoe.dll - WMV9 Advanced Profile Encoder DMO BETA
wvc1dmod.dll - WMV9 Advanced Profile Decoder DMO
WMCmd.vbs - Updated WME9 command-line encoder script

Install requirements:
Windows XP or Windows Server 2003 SP1
Windows Media Format SDK 9.5 or Windows Media Player 10

VC-1 ain't twist, it is a SMPTE VC-1 Standard (used on Blu-ray and on HD-DVD discs also). And it will be supported on coming ffmpeg VC-1 decoder, the point is to support VC-1 and WMV3 files are VC-1 decoder combatible.

Could you check 0.8.5-final View -> Messages while opening that VC-1 file and tell if video codec ain't identified. That would tell that VC-1 wan't supported by the time of release (because VC-1 decoder didn't exist at that time) and why nightlies work.

After installing the WVC1 codec the files worked in VLC 0.8.5 dated 1/15/06 but did not work in VLC 0.8.5-Final. So if what you say is true, it should not work at all in any version! In Stream an Media Info... the codec is identified correctly. As for messages I found it very difficult to sort out for all reg numbers being called.

But I guess the bottom line is that you say, this will be resolved in the next revision. Are you sure?

Thanks for the response!

http://download.microsoft.com/download/ ... vc1dmo.exe

The package includes:
wvc1dmoe.dll - WMV9 Advanced Profile Encoder DMO BETA
wvc1dmod.dll - WMV9 Advanced Profile Decoder DMO
WMCmd.vbs - Updated WME9 command-line encoder script

Install requirements:
Windows XP or Windows Server 2003 SP1
Windows Media Format SDK 9.5 or Windows Media Player 10

Will this also work in Windows XP SP2?

Yes it works for SP2. XP SP2 is soon only supported version of XP.

Sorry for the dumb question! I went to Microsoft's web site shortly after my last post and discovered the answer and downloaded the codecs. Just haven't had time to try it yet.

I did notice this is relatively new (June 06 I think) and still in beta. This still leaves me wondering why VLC worked in a earlier version and doesn't completely work in the current version. Also have discovered that some files in 720p 30fps are very choppy in VLC and not so under dshow. Specially when the same codecs are in use in these versions. VLC does show higher CPU usage than the dshow players and to me this is also a mystery????

If you can give links to sample files or upload them to somewhere it would help to check out CPU usage.

The 60 meg 30fps 720p of Alan Wake seems to be a reasonable example.

I would suggest downloading it so streaming would not be part of the issue. Also makes it easier to compare CPU usage to other players MPC, WMP 10, etc.

http://www.alanwake.com

Just so you know: ffmpeg are developing a VC1 decoder (part of Google's Summer of Code project) which will be included in VLC once it's done and allow native playback of WMV3/VC1 encoded videos. This should be available at the end of summer.

I had that Alan Wake trailer ealier, but deleted it, now I downloaded it again and tested. And yes, it lags more on VLC than on WMP, then I set Audio -> Audio track -> Disable and it plays MUCH better, it is also nice to notice that 5.1 WMA is supported (I can choose Audo -> Audio device -> 5.1).
Also when playing with audio, messages say
main warning: audio drift is too big (-178624), clearing out
main debug: audio output is starving (203611), playing silence

so maybe the same problem than with AC3 (SPDIF) output ?

Is it possible to see audio and video thread times from somewhere?

Shutting down audio is not a valid test as there is no sync and the video runs free and generally not on speed.

Changing the audio output module may shed some light.