3D MVC Option

[sinious]

Alright, that straightens out a few black holes for me.

docchris ~

Yes I do realize part of a TVs job is to be compatible with the glasses. I am fully aware of polarizing and how active shutter and passive work. I realize the TV must take an otherwise "not converted for your TV" source and apply a filter to either eye to assure the content is compatible with the glasses. That wasn't really ever a question with me because I have zero control over this, it's up to the TV to handle. What I do have control over is the 3D format I export (because I said I was CREATING content earlier, and can output F/H SBS/TAB/Interleave/etc). This conversation then became about headers, metadata, EDID handshake and the sort, all because I'd like to trigger the TV to 3D and tell it if the source is TAB/SBS/etc.

SiliconKid ~

I was reading into something a bit wrong. The term "Frame packed" has been lingering in my mind. What wasn't obvious to me was how a blu-ray could have full resolution data for each eye yet still be 1920x1080 @ 24/29.97/30fps. How do you get double data from a single frame? Then you mentioned the missing ingredient to me:

Full-SBS and Full-TAB formats where there is no compression of frames and the frames transmitted are massive double sized frames

Double sized frames.. Therein lies the answer to how the extra resolution is handled.

What I understand but disagree with is that, given a Full HD source, that a TV cannot use any particular mode (TAB/SBS/etc) to display. Considering ALL of the frame data is available, it is an absolutely trivial task to cut the left eyes frame from the right eyes frame in SBS or TAB (interleave is slightly harder), regardless how it's encoded. I can then filter the content based on what the 3d glasses are expecting for that frame and display it in TAB/SBS/Interleave/etc.

I could also do it even if H-SBS/TAB was used as well, although the same interpolation to achieve a full frame will be required. That does not mean the display NEEDS to be the same way it was packaged.

I know you might be saying "why go against the way it was encoded?". The simple answer is, on other forums where I asked about this, most people actually prefer TAB, although as you noted, most content is delivered in SBS. I myself prefer TAB. I generated the same bunch of animations in 3D using HSBS and HTAB, adjusted my TV to the correct mode and watched all of them. IMHO, I also prefer TAB. For whatever reason fast moving content close to the screen (so to speak) doesn't bother my eyes nearly as much as it does in SBS, and I have no idea why.

Thank you both for filling in that extra information.

[SiliconKid]

@sinious:

Let me see if I can clear up a few more things that I think you are still misunderstanding:

1. The reason BluRay and MVC can deliver full HD to each eye is because there are TWO (2) video streams in that case. There is a totally separate video stream for each eye !

That means TWICE the amount of frames to 2D, twice the amount of data, twice the bandwidth to carry it.

If you MediaInfo an MVC MKV or source BluRay rip you will discover a completely separate video stream for each eye, with each stream being a Full HD stream.

And in fact, if you just play the stream for the Left eye, you get the 2D movie !


2. I think I may have confused the issue for you by using the term "encoding" when I should probably have rather used the term "packaging".

When I talk about "encoding", I also mean "packaging". In other words how the frames are packed into the media file. I've been using the term "encoding" to mean
multiple things ie. The actual video format (H264 or whatever) AND how the frames are packaged for 3D (HSBS or HTAB or 2 video streams for MVC).

Yes, you can choose whatever "packaging" method you like when you rip and convert the original source material (typically a purchased 3D BluRay disc in most cases), but when you play
the file you produced, you will need to put your TV into the 3D mode that matches the type of packaging you opted for, and THAT is not optional or a choice, you MUST put your TV into
the 3D mode that matches your source material for the 3D movie to play correctly.

Just please understand that you cannot flip between 3D modes on-the-fly. You have to pick a mode when you create the file and package the 3D data in an explicit way and then you are locked into
playing that file in that mode.

You CANNOT send the TV and HSBS stream and then put the TV into HTAB mode and expect it to work. The mode you put the TV into tells it how to decode and unpack the incoming frame stream,
it does NOT influence the display of those unpacked and decoded frames in ANY way at all.

I'm just concerned that you seem to think you can send 1 specific type of 3D content to the TV (HSBS for example) and then flip between the various 3D modes on your TV when viewing that 1
source to get different viewing results.

"That does not mean the display NEEDS to be the same way it was packaged."

Yes, the display does NEED to be put into exactly the same 3D mode as the encoding / packaging mode used when the media you are playing was created. ALWAYS.

I don't know if that is what you think or are understanding, maybe not, but if it is, that's wrong and you can't do that.

[fetef]

I just read fetef's post again and I think I misunderstood him the first time around.

What he's actually saying is:

1. New Samsung TVs can play MVC 3D properly if it's in an M2TS container using onboard decoding.

2. You can send an MVC 3D movie in an M2TS container to the TV via Plex without affecting the video streams if you use the "Direct" mode in Plex thereby avoiding any Transcoding completely.

3. He tried both the MVC versions (in an M2TS container) and the SBS versions (in MKV containers) of the SAME movies to compare results and found that the MVC versions were far better quality, which makes logical sense because they will be encoded at Full HD for both eyes, every frame. I misread this the first time round, sorry fetef.

Hi SiliconKid, Thanks for your reply, and thanks for simplifying my original post, i think you better explained what i meant. Your three points are essentially what i have experienced. Sorry it took me so long to confirm this, but it was my first post on the forum, and it took a while to get cleared.

Plex doesn't have an MVC (Blu-ray 3D) decoder, as libavcodec doesn't have one. This could maybe work via hardware-accelerated decoding, but you should ask on the Plex support forum, not here.

It is very true that plex doesn't support 3D at all. Not even the third party Samsung Plex App, which i am referring to, officially supports 3D-MVC, because, as the developer puts it: only a few samsung devices support it. I was very sceptical at first, and it took a lot of searching forums for people who could confirm that this would work, before i would even commit to sparing the 5 minutes it took to remux a 3D MVC MKV to M2TS. I am convinced that it is not conversion for the following reasons:

-My original reference film was Desolation of Smaug. I freely admit that I watched this film in 3D IMAX twice at the cinema, and I own the 3D Blu-Ray, which I have watched 3 times, and a 3D SBS mkv ripped with DVDfab, which I have watched once with Plex for Samsung and once with VLC (manually switched to SBS output on TV). Suffice to say I have seen and loved this films lots of times in 3D and I know which bits will be at which depth in particular scenes. The 3D MVC M2TS played on the samsung gives the same 3D effects as all the other versions that I have watched. Unless 2D to 3D conversion has become very accurate, it seems to be authentic output.

-when outputting on the samsung app, the TV automatically switches to 3D mode. But this isn't normal 2D to 3D mode, where three options are given: conversion; SBS; TAB. The 3D is either on or off, indicating that the TV knows that it is receiving 3D.

-Numerous other users, on this forum and the plex for samsung forum have confirmed that it works for them, either through USB or through Plex for Samsung, and there is documentation somewhere that confirms that new models samsungs support MVC files

-Plex Server confirms that it is direct playing the file (no transcoding). While plex doesn't support any 3D formats, it can serve up any file in an m2ts container and it is down to the client device to decode it. so far, only my TV has done so, my iOS devices haven't been able to play the file at all, either through direct play or through transcoding (admittedly i haven't tried with the desktop PLEX client, but VLC outputs as 3D)

I'm convinced, but I can understand the scepticism, it does sound too easy to be true. TBH the easiest way for me to test this would be to use that naming convention (.3D-MVC.m2ts) on a normal 2D film and see what happens. I'm on holiday at the moment though and can't test that until Sunday. maybe someone else with a similar setup could test that? I would also say that the fact that the TV automatically detects 3D MVC m2ts files over USB would be faily conclusive as well, but i haven't personally tried this yet. Again, I will test that on sunday, but somebody else may be able to confirm before then?

Eternally grateful to Makemkv

Alex

EDIT: Further to what I said above, I was able to pop home to my server(I'm not actually on holiday, but i have to live at my workplace until sunday) and I ran a quick test with a 2 2D mkv that i ripped earlier. tsmuxer confirmed no MVC track present, so i remuxed to m2ts, added the .3D-MVC tag to the filename, added to server directory and rescanned with PMS. PMS confirmed file added, so i loaded up plex for samsung, played the file, and BOOM.... no 3D. no activity on the TV's part. press 3D button, gives me the usual convert, SBS,TAB options. nothing automatic. run Desolation of Smaug again, and 3D is automatically turned on again. I rechecked that I had done everything identically with the two files, and I had, other than checking the MVC file in makemkv and Tsmuxer for the 2D film, as those options weren't available. I'm utterly convinced, but will run tests with USB and alternative naming on Sunday

[SiliconKid]

The research that I've done into all of this recently revealed 2 things:

1. Some of the new TVs are actually reading header flags in the files now, particularly from MKV files, to determine the correct
3D mode automatically. This only works if the TV itself is decoding the file and can get access to the file as whole so it can
interrogate the header information, obviously.

See one of my posts higher up where I detailed exactly which header flags in an MKV file influence this.

2. It's very possible that the new TVs are actually reacting to the fact that there are 2 video streams in an MVC file.

In theory, all they would have to do is check if a file has 2 video streams, and if so assume it's MVC 3D and immediately
switch to Frame Sequential 3D mode.

There is basically nothing else that would result in more than 1 video stream in any given media container so that would be
a pretty safe assumption to make in my opinion.

In this case, it's conceivable that the TV could do this evaluation without direct access to the source file but that's pure
speculation on my part at the moment.

Given that you only get it to work when using Direct mode via Plex, I suspect that success still hinges on the TV getting
access to the file itself, raw, which is presumably what happens when you play something in Direct mode via Plex.

[fetef]

Indeed, direct play just means that the file is served up across the network by the server in it's untouched form, when requested by a client device. In direct play mode, plex server doesn't care if the file can be played by the client or not, if the client doesn't support the format, the file doesn't play, but the server still registers that it is serving up the file.

in my case, this is done over Ethernet. Cat 6 cable from the Intel Gb NIC on my server, to an unmanager Gb switch, then more cat6 cable to the TV. I assume that the ethernet port on the TV is limited to 100Mbps, but so long as everything upto that point is Gb, it should be fine. The MVC Blu-Ray spec is up to 60 Mbps i believe, so 100 Mbps is fine, but as with playing ISOs of the network, you don't want any bottlenecks in the drives or network. I would say that Wifi would probably be a no go, but that depends on your setup. Since it is direct play, plex won't reduce file size to fit the network, so if the network can't handle the file, it will buffer or not play at all.

[docchris]

2. It's very possible that the new TVs are actually reacting to the fact that there are 2 video streams in an MVC file.

In theory, all they would have to do is check if a file has 2 video streams, and if so assume it's MVC 3D and immediately
switch to Frame Sequential 3D mode.

Just to add to this.

it isnt actually two discrete video streams (as you would get for something like the picture-in-picture directors commentary or the like, with two whole separate video streams)

The reason why MVC maintains its backwards comparability (with 2d players) so well is that it is a single, normal, AVC stream... and the second stream only encodes the differences for the "other" eye. (which is why the file size only grows by about 50% rather than the 100% you would expect if you encoded a whole extra eye - but still allows compatible hardware to generate two full 1080p images). It also means that non-3d players simply dont understand and ignore the secondary stream, and just play back normally.

incidentally hobbit is one of the very few blu-rays that has the "right" eye as the base stream, on most its the "left" eye. (there is an option in bluray authoring programs to flag which eye the "full" stream is, and therefore which eyes the "delta" stream is) (and thats from memory - it might be that the eyes are usually the other way around, lol)

Also, just as an interesting side note. the headers can only flag that he 2d picture is to be displayed as 3D in SBS/TAB format etc.. because those things are codec agnostic. There is no header to say that this is an MVC stream, because they did not want to add codec dependent headers into the MKV standard (and also a program should be smart enough to know that if the codec is MVC, that its a 3D stream, without any additional headers).

That is something Cyberlink seems determined to not understand. Anytime you contact them regarding MVC in an MKV file, they start whining on about the authoring program not setting the appropriate headers, and that is why it wont playback in 3D, when in fact there are correctly, none.

[docchris]

What I understand but disagree with is that, given a Full HD source, that a TV cannot use any particular mode (TAB/SBS/etc) to display. Considering ALL of the frame data is available, it is an absolutely trivial task to cut the left eyes frame from the right eyes frame in SBS or TAB (interleave is slightly harder), regardless how it's encoded. I can then filter the content based on what the 3d glasses are expecting for that frame and display it in TAB/SBS/Interleave/etc.

I could also do it even if H-SBS/TAB was used as well, although the same interpolation to achieve a full frame will be required. That does not mean the display NEEDS to be the same way it was packaged.

I'm sorry - I still completely fail to understand what you are trying to say here

"That does not mean the display NEEDS to be the same way it was packaged. "

The display mode cannot be changed - that is how the light comes out of your tv set... its a function of what hardware you have!

for passive tv's , it will always be polarised interlaced lines. for active TVs it will always be full frames flashing at alternate eyes.

Whatever source you feed into the TV.. whether its frame packed, SBS, TAB, even checkerboard, the TV simply has to convert the incoming signal to whatever output the TV was built for.

"What I understand but disagree with is that, given a Full HD source, that a TV cannot use any particular mode (TAB/SBS/etc) to display"

thats the bit that baffles me... tv's dont DISPLAY in those modes... the INPUTS are in those modes.. the TV displays a 3D picture according to whatever type of 3D it was constructed for

[sinious]

@sinious:

1. The reason BluRay and MVC can deliver full HD to each eye is because there are TWO (2) video streams in that case. There is a totally separate video stream for each eye !

That means TWICE the amount of frames to 2D, twice the amount of data, twice the bandwidth to carry it.

To be really clear, the above quote is what you meant when you said F* sources are:

frames transmitted are massive double sized frames

So those frames aren't 1920x2160 (FTAB) or 3840x1080 (FSBS)?

For the "selecting a display mode" confusion, I just want to touch on it because ultimately I understand and agree with you that you must (currently) put your TV on the display mode the 3d video was prepared for, TAB/SBS/etc. But this does not mean that me, as a person who has worked on creating video for over a decade and has programmed dozens of custom (CPU/GPU-based) media players in Flash, that I cannot do anything you can possibly imagine with the input I receive. In this case I'm saying a stream can be converted from SBS/TAB/Interleave/etc to anything else. And again, I realize you've said TVs today do not do this.

When it comes down to video in code, the easiest I can explain is it's like a giant spreadsheet. Each pixel is displayed in rows and columns, containing certain values of varying types. To keep it very simple, in HSBS, I can programmatically separate the left eyes portion (row 1 pixel 1-960 to row 1080 pixel 1-960) from the right eyes portion of the frame (row 1 pixel 961-1920 to row 1080 pixel 961-1080). I can then use any algorithm I choose to stretch each frame from 960x1080 to 1920x540. I can then stack the left eye on top (1920x540) and right eye on bottom (1920x540), or vice versa on the eye stack order. Doing so will have the already associated horizontal quality loss (inventing pixels) and then you'll suffer a vertical quality loss 1080 down to 540, albeit higher quality than horizontal. And this will work as HTAB. I know, because when I'm told something can't be done, I do it. I read a video file I created in HSBS, performed this conversion and streamed it to a DLNA server which my TV can see, and HTAB worked. Although the picture was noticably degraded, it was still markedly better than DVD.

That said, suffering the quality loss is a good reason a TV wouldn't bother converting the signal on HSBS and HTAB.

However...

If you have 2 full frames? Whether it's 2 streaming sources or jumbo frames like I thought you meant, I can convert that into SBS/TAB/Interleave losslessly at my whim. I don't understand at that point why a TV wouldn't give the user their choice. It took less than 3 hours to make an example, you'd think a TV engineer could do the same, especially when TAB seems to be peoples choice.

[docchris]

I don't understand at that point why a TV wouldn't give the user their choice.

but WHAT choice??? thats what im not grasping...

where do you expect the TV to put this "output"?

If its being fed two full frames....

and the output from a tv is the light coming out of the front...

where do you seem to think this additional conversion layer is happening?

[docchris]

and yes, you can convert between any of the 3d formats that you like using a computer, with or without loss depending on what you are doing.

but that doesn't affect the tv at all!! it can only take a single input of your choosing/design - and output it through the screen.. there is no level of choice that it is possible for the TV to give you?

you say you dont understand why the TV doenst give you a choice... but i dont see what choice you expect it to be able to give you?

please explain clearly the choice you would like the TV to give you?

[docchris]

At the moment the TV is doing:

HDMI Full frames -> TV output (whatever format that may be, active/passive )

or

HSBS/TAB -> TV screen (whatever format that may be, active/passive )

you seem to think that it is doing:

HDMI Full frames -> HSBS/TAB -> TV output (whatever format that may be, active/passive )

and that is the choice you want? Am i understanding you correctly? but that stage does not happen...

[SiliconKid]

@sinious:

The problem is that your argument, while very clear, just makes no logical or practical sense.

WHY would you want to change the format ? The 3D format is purely a DELIVERY mechanism, it has NOTHING to do with how you view the content or how your eyes perceive what you are viewing.

All of the available 3D formats (delivery mechanisms) will result in the SAME viewing experience.

"I can convert that into SBS/TAB/Interleave losslessly at my whim"

No, you cannot. If you convert full HD source to Half-SBS or Half-TAB, you will lose half the original resolution due to compression on 1 axis, and that is not lossless.

You CAN losslessly convert full HD source to FULL SBS/TAB, but why would you ever want to do that ? The only possible reason is because your transmission medium can't transmit MVC but
can transmit FULL SBS / TAB, so you are forced to convert in order to transmit, but that scenario is highly unlikely in the first place. The typical situation is that the transport medium can
handle HALF SBS/TAB, but not MVC, in which case conversion makes perfect sense.

"I don't understand at that point why a TV wouldn't give the user their choice."

Because there is absolutely NO reason for the TV to ever convert what it received from one format to another. There is ZERO to gain from doing that.
The TVs 3D mode is the DECODING mode, NOT the display mode, and it does not affect how you see the movie at all.

You mentioned something previously about TAB affecting you differently to SBS. That makes NO sense at all, because your TV will NOT display TAB differently to SBS.

And this is where you still seem to be confused. There is absolutely no point in converting from one format to another after the TV has already received the media. The
TV will decode the media to the exact SAME internal format BEFORE it displays it and sends it to the 3D glasses anyway, so dynamically changing formats on the fly would
be nothing but a complete waste of time and energy, literally, and accomplish nothing.

Irrespective of how you encode / package the content and deliver it to the 3D TV, the TV will only show it to you ONE way.

You can convert one 3D format to another, and to another, and so on, all day long, it doesn't matter, and all the formats will work, but ultimately your TV take whatever format you send it and internally convert that into ONE STANDARD INTERNAL FORMAT of it's own that it uses for the actual display and transmission of frames to your 3D glasses.

So the fundamental point here is that the 3D format you choose only matters in terms of:

1. Quality

2. Bandwidth used to transmit it.

It does NOT affect your viewing experience in terms of how your eyes perceive things other than from a quality perspective.

Half-SBS and Half-TAB are the same quality, they both incur the same loss of resolution when packaged, so they will both look IDENTICAL when you view them on the TV.

You will not see any difference because irrespective of whether it's Half-SBS or Half-TAB, the TV will decompress the frames and create a Frame Sequential stream of frames that it will then send to your glasses, and that Frame Sequential stream will be IDENTICAL for Half-SBS and Half-TAB.

As you pointed out though, if you take Half-SBS and convert that to Half-TAB, you actually incur a double resolution loss, which is just completely insane.

There is absolutely no reason whatsoever to EVER convert Half-SBS to Half-TAB or vice versa. None.

There is a reason to convert BluRay source or MVC to Half-SBS / TAB because you will end up with a smaller file that costs less bandwith to transmit, so I can understand that.


And with regards the oversized frames, that applies to Full-SBS or Full-TAB, that does NOT apply to BluRay 3D or MVC.

As explained in detail by docchris, in an earlier post, BluRay 3D and MVC contain a separate stream for each eye at full res, but the right eye stream is generally 50% the size of the left eye stream and is referred to as the delta stream.

[docchris]

Actually i do get his point about HSBS/HTAB for passive TVs - since they only display 540 lines per eye anyway, HTAB does make more sense for them, since the HTAB resolution per eye matches their output per eye, and you keep the full 1920 horizontal resolution

but if you are feeding the damn thing full frames anyway, then yes, as we have both said, why would you do any other conversion internally?! its simply

full frames -> polarised screen

nothing else

[SiliconKid]

Yes, ok, I accept that, but really that's such a technicality and such a needless optimisation at the end of the day.

And I still say that Half-SBS and Half-TAB will ultimately result in the exact same viewing experience anyway. But maybe that's just me and my eyes.

It still doesn't change the fact that he seems to think that he can flip between 3D modes on his TV after it receives the video stream and that's somehow going to change his viewing experience ?

[docchris]

Yep