3D MKVs and WD TV

Joey and I have been having  a back-and-forth over in the “Ideas” section, but I thoguht it might be interesting to continue the talk here to see what other insights folks have. The short version is I wondered if the WD TV unit would be able to play the 2D portion of 3D mkv files with a future update. I’m not talking about SBS/TAB here (sidenote: those solutions seem wasteful and inelegant). I’m referring to the specification that uses a suppliment to add the 3D information to a 2D stream without combining the two into a single stream or file, allowing for backwards compatibility. Right now it seems to play the audio and subtitles of a 3D mkv, but not the video.

The impetus of this was so that I could keep one file out NAS for use by both my 2D and 3D media devices.

tribunal88 wrote:

Joey and I have been having  a back-and-forth over in the “Ideas” section


I hope you mean “A Friendly Discussion” :smiley:   anyways … i’ve said i don’t believe it will ever be implemented.

agree to disagree ?  … i will happily eat my words and apologise if i’m incorrect  :smiley:

just have to wait for an Official WD Response  (which could be months or years)

Yes indeed. It’s definately a friendly dicussion.

Basically the answer to your question is no.

Yes mkv is just a container, however inside the container is a codec, specifically MVC which is an amended h.264 compression and the SoC in the WD TV’s is unable to decode this codec.

Unlike your PC, which is able to use software, the WD TV’s do not use software since they are firmware based and therefore rely on hardware to do the decoding.  The only way to be able to do what you would like to do is to update the hardware since the current SoC is not capable of decoding MVC, which would be necessary to extract the 2D stream.

No firmware updates would rectify this, since the decoding is “hardware locked”.

EDIT:  Even if the WD TV’s were able to software decode MVC files, you would get terrrible playback since software decoding takes much more processing power, and the Sigma chips in them are no where near up to that task.

Tinwarble wrote:

…  inside the container is a codec, specifically MVC which is an amended h.264 compression and the SoC in the WD TV’s is unable to decode this codec.

I agree with thie statement 100%. But I never suggested that it should decode the MVC stream. In fact, I want it to ignore it entirely.

This seems to be the source of a lot of confusion. There are 2 distinct video streams inside the MKV file. A “Base” stream, which is the same stream found on a standard Blu Ray 2D film (identical, bit-for-bit). It then suppliments this stream with a second stream (MVC) which gives 3D players the extra information to create a 3D image. It was done this way specifically to provide backwards compatiblity with existing non-3D Blu Ray players. So, if all you want is a 2D movie, then the MVC stream can be ignored entirely and the standard stream played back.

See  this explanation direct from Sony, specifically paragraph 2.

As it stands, it is not detecting the AVC stream properly inside the MKV file. I agree that the WD TV software is clearly not peroforming the decoding, and will be bound by the limits of the current hardware for its lifetime. But, I suspect the software is detecting file contents and formats, and then sending the audio and/or video streams to the SoC with an explicit system call. The SoC then takes care of performing the appropriate decode process, having been given direction by the software as to which codec to apply.

I could be totally wrong. It could also be throwing raw files at the SoC and letting it sort everything out itself, but that would surprise me. Reading file attributes and metadata is typically the responsibiltiy of the software layer. Rendering/decoding specific information is the responsibility of the hardware layer. For instance, the software layer would not typically say “play this file”. It would say, “You will be playing an audio stream. Here it is, and it’s format is MPEG Layer-3”. Or “You will be playing a video stream and an audio stream synchronously. Here is the video stream, and it’s format is H264 AVC. Here is the audio stream and it’s format is DolbyTrueHD.” Hardware is very good at performaing specific tasks, but it usually requires equally specific direction. That’s where the software comes into play.

I did some more intkering and found some new info. I tried a different 3D file with the same results as before, but here’s an interesting thing. When I played the 3D file that contained the MCV stream, the subtitle was presented in 3D. When I played the same file generated without the MCV stream, the same subtitle stream was in 2D. So I’m not sure if the WD TV is actually attempting to play it in 3D or not.

Since this post is almost 5 months old has there been any updates either from users or WD as I’m experiencing the same issue?

What I find interesting is I have several older devices around the house that have no problem playing only the 2D stream.  My 5 year old LG smart TV will play the 2D stream of my MKV’s as well as my HTC One M8 and my 3 year old 32" Samsung TV and yet my WD TV will not.  The only reason I purchased the WD TV is for my LG.  While it can play the MKV’s it simply doesn’t have the processing power to do so smoothly.  There’s simply no reason why WD cannot bring this functionality to its media players.  I’m hoping they provide an update soon but they probably won’t.  

Nope. I use my WDTV just about every day, and this is the one of the few complaints I have with it. They just did a firmware update, but nothing in the notes about this being added. I have to admit, that until they fix this, I’m think Chromebox + Kodi for my next Media Player.