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3d Tvs - What Does A 3d Blu-ray Player Do?


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#1 aeon

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Posted 01 January 2012 - 11:25 PM

Hi all, a friend of mine recently purchased a Sony 46HX820 display, which is a 3D capable LCD TV.

I download a few sample 3D files for him the other day, and we played them on his TVIX, which as far as I know is not a device that is advertised as "Supporting 3D".

However, we were able to play the files fine, and view them on 3D on his TV. One of the files, the TV Automatically detected it was a 3D signal and it started playing in 3D, however on some of the other files, when they started playing, there were two images side by side. On the TV however, he was able to click on the 3D button and chose the "images appear side by side" option, and the file then started playing in 3D again.

So my question is - what's the difference between doing this on a standard media player without 3D support, vs an ACTUAL 3D Blu-ray player for example, is there something different in the signal? My Popcorn Hour A210 for example is advertised as being an ACTUAL 3D player. If the TV is able to convert a downloaded video clip which has side-by-side images in the video into a proper 3D signal, what is the actual use for a device that is advertised as supporting 3D?

(there might be something I'm missing, as I'm not really across 3D technology, as I don't have any interest in watching anything 3D! however because my friend posed the question about why he needs a 3D Blu-ray player, I'm actually interested in knowing the technical reason).

#2 alanh

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Posted 02 January 2012 - 03:04 PM

aeon,
Stereoscopic vision is where you use a pair of images which were captured by a pair of cameras the average eye distance apart. When this pair of images are displayed separately to each of the viewers' eyes, the illusion of depth is created. This is what you are calling 3-D.

There is a pair of systems for conveying these images from the camera to the viewer.

* Frame compatible method. This is where on each row of pixels each alternate pixel is removed. This makes the image half as wide. So the left image is sent first followed by the right image, this process is repeated on each row on the displayed image. Also these signals are always interlaced scanned.
So the 2D resolution from a Blu-ray disc drops from 1920 x 1080 progressive to 960 x 540 on each field. There is one of these signals for each eye.

* Non Frame compatible method. In this method the signals from the camera are combined into a 1920 x 1080p signal. This is identical to the standard Full HD signal. To display depth the distance between edges with in the image in the horizontal direction are measured. This produces a second 1920 x 1080p signal. When the Blu-ray player plays this MVC-MPEG-4 compressed signal it creates a pair of 1920 x 1080p images in its memory. The depth signal then is added to the read clock in the appropriate RAM image which moves it sideways. The human perception system cannot determine distance as accurately as position, so each 2D pixel is represented by an 8 bit byte, but the depth signal is only a 4 bit byte. This principle also applies to the sharpness of all colour TV where the sharpness of the colouring in signal is twice as blurry as the monochrome signal.

Non Frame compatible method is only used in commercially produced and manufactured 3-D discs at this time.

So a 3-D Blu-ray player is required for 3-D discs. It will of course show 2-D Blu-ray discs. An HDMI 1.4 cable is needed to connect the Blu-ray player and the 3-D TV. This is because to send a pair of 1920 x 1080p signals in the time of one will require double the data rate.

AlanH

#3 hrh

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Posted 02 January 2012 - 07:02 PM

Whilst the above post has gone into a fairly technical long winded post, it hasn't actually answered the question posed.

"So my question is - what's the difference between doing this on a standard media player without 3D support, vs an ACTUAL 3D Blu-ray player for example, is there something different in the signal?"

I will state that I don't the answer, but would hazard an educated guess that with a file that plays/shows as 3-D straight away, it has a bit in its information to tell a 3-D capable TV that the program is indeed 3-D, and the other file(s) don't have this bit so the TV has to be forced into 3-D mode manually. And/or a player listed as having 3-D support versus one that doesn't, may or may not pass on the information to do the auto switch function.

This is just a guess and by no means definitive.

#4 Fatbeer

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Posted 02 January 2012 - 08:50 PM

So my question is - what's the difference between doing this on a standard media player without 3D support, vs an ACTUAL 3D Blu-ray player for example, is there something different in the signal?


Generally all '2D' media players will play a (half) side-by-side 3D image, however, you generally get a loss of quailty as AlanH has stated and the resulting resolution will be less than 1920x1080p.

A 3D Blu-ray disc from a 3D Blu-ray player will have no loss of resolution and be in 1920x1080p. It also perserves the HD sound.

That is generally the difference. You can get full HD side-by-side 3D, but the resolution is 3840x1080, and currently not very common and not supported by *most* current media players. This where next gen "3D Media Players" might come in handy.

Edited by Fatbeer, 02 January 2012 - 08:53 PM.


#5 aeon

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Posted 02 January 2012 - 10:41 PM

Ah! Thanks for the replies - I think I get the general idea now!

#6 MLXXX

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Posted 03 January 2012 - 12:05 PM

* Non Frame compatible method. In this method the signals from the camera are combined into a 1920 x 1080p signal. This is identical to the standard Full HD signal. To display depth the distance between edges with in the image in the horizontal direction are measured. This produces a second 1920 x 1080p signal. When the Blu-ray player plays this MVC-MPEG-4 compressed signal it creates a pair of 1920 x 1080p images in its memory. The depth signal then is added to the read clock in the appropriate RAM image which moves it sideways. The human perception system cannot determine distance as accurately as position, so each 2D pixel is represented by an 8 bit byte, but the depth signal is only a 4 bit byte. This principle also applies to the sharpness of all colour TV where the sharpness of the colouring in signal is twice as blurry as the monochrome signal.

Most of the above is from Alanh's imagination.

Simple sideways displacement is how old depth based 3D systems used to work. Those old systems could not handle transparency and occlusion and were a poor man's 3D. That simple method is rarely used today. For one thing it is computationally very difficult to generate simple 2D + depth from discrete left and right camera images of real life. The MPEG-4 MVC codec as used for 3D Blu-rays is not simple 2D +depth, but rather main + difference. [I have explained this to Alanh many times in the past, but it never seems to sink in.]

With MPEG-4 MVC used for stereoscopic 3D, the main channel can be used to carry the Left hand camera image, and the difference channel to carry the Right hand camera image (when decoded in conjunction with the main channel).

_______

With 3D Blu-ray discs of Full HD movies, the 3D player decodes the MPEG-4 AVC main and difference channels into Left and Right views and assembles them [assuming use of a Full HD 3D television set] in the standard Full HD "over under" format of 2205 pixels total height and 1080 pixels width. This is sent via HDMI to the Full HD 3D television set. See http://hdguru.com/3d...explained/1336/

This type of signal is immediately recognised as being in a 3D format by the display. No need to set 3D mode manually. (There is also a similar mode available for 720p "over under".)

Edited by MLXXX, 03 January 2012 - 12:09 PM.


#7 alanh

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Posted 03 January 2012 - 04:04 PM

MLXXX,
MVC-MPEG-4 can encode up to 6 images simultanously so that the viewer can get a view from the sides and behind giving true 3-D system. However now there is no commercially available hologram display system.

Where is your proof of the difference?

HDMI does not use the over under method. This is only used for the transmission of S3-D 720p signals. HDMI sends all image components as packets. It sends the following program related packets
Left Luminance, Left Pr, Left Pr, Right Luminance, Right Pr and Right Pb as well as sound packets.

When the signal was a Non-frame compatible signal in the compressed states are Luminance, Pr, Pb, depth, sound and control signals.

I have contacted the HDguru on other matters. He is not working in the industry so his information is just as valid as yours!

You need a 3-D Blu-ray player to view non frame compable signals, regardless of what illusions you have. The Non-frame compatible images give the best results over frame compatible in the real world.

Lastly in the control room the stereo images are converted into main and depth signals so that the depth controller can adjust the depth between cameras in a multiple camera production and to match the program content.

AlanH

#8 MLXXX

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Posted 03 January 2012 - 05:24 PM

QUOTE (alanh @ Jan 3 2012, 04:04 PM)
MLXXX,
MVC-MPEG-4 can encode up to 6 images simultanously so that the viewer can get a view from the sides and behind giving true 3-D system. However now there is no commercially available hologram display system.

Where is your proof of the difference?

HDMI does not use the over under method. This is only used for the transmission of S3-D 720p signals. HDMI sends all image components as packets. It sends the following program related packets
Left Luminance, Left Pr, Left Pr, Right Luminance, Right Pr and Right Pb as well as sound packets.

When the signal was a Non-frame compatible signal in the compressed states are Luminance, Pr, Pb, depth, sound and control signals.

I have contacted the HDguru on other matters. He is not working in the industry so his information is just as valid as yours!

You need a 3-D Blu-ray player to view non frame compable signals, regardless of what illusions you have. The Non-frame compatible images give the best results over frame compatible in the real world.

Lastly in the control room the stereo images are converted into main and depth signals so that the depth controller can adjust the depth between cameras in a multiple camera production and to match the program content.

AlanH


Here we go...

Yes, MPEG-4 MVC can make available multiple images.

Where is my proof of difference? Well one simple observation would be to halt a 3D movie playback on a frame including a close up image of a face and see that the image for the right eye includes more of the right ear lobe than the image for the left eye. That is not the result with simple 2D + depth. All that protocol manages to do is to move content to the left or right. It cannot add new pixels from a new view. It has only a single view to work from. Another approach would be to use software to decode a Blu-ray 3D frame and observe differences between the Left and Right images for foreground content. [N.B. A poor 3D simulated movie may fail this test. A genuine 3D movie would not.]

The syntax/protocol for creating packets of video and audio for HDMI for a frame is of no consequence if when reconstituted the frame contains Left and Right views on top of each other in an unusually high frame. [Where you get your info from such as "HDMI does not use the over under method. This is only used for the transmission of S3-D 720p signals." mystifies me. The use of the over under method appears all over the internet. If you try some research that is what you'll find, repeatedly.]

The following info is included in the specifications for a home projector ( http://www.optoma.eu.......nt&PC=3D-XL ):-

3D Compatibility Side-by-Side:1080i50, 1080i60
Frame-pack:1080p24, 720p50, 720p60
Over-Under: 1080p24, 720p50, 720p60



This info is included in the specifications for a device that accepts 3D Blu-ray input ( http://3dfury.com/?page_id=30 ):-

■3D MODES INPUT COMPATIBILITY:
■Full 3D HD 1080 (per HDMI) (Blu-ray): 1920 x 2205 24Hz
■Full 3D HD 720 (per HDMI) (Blu-ray): 1280 x 1470 60Hz

Such information is not hard to find, alanh.

I'd also refer you to this article:
http://www.tomshardw...-tv,2632-6.html
which includes:

The highest-quality method to encode and deliver a 3D video program is to store and deliver it as a dual-stream synchronized video program, with one full-quality video stream for each eye. This is how Blu-ray 3D works, storing the video for each eye as a full "Blu-ray quality" video program.

The HDMI 1.4 specification provides for 3D stereoscopic video to be delivered in several different ways, including over/under-formatted frames that are 1920 pixels wide and 2205 pixels high. The frame for the left eye and right eye are delivered together, to assure that synchronization is always maintained, even if the signal is momentarily lost and then restored.




And I'd refer you to the article (today's date) at http://thetechjourna...werdvd-3d.xhtml
which includes this:

Just like other video formats, 3D is transmitted one way and usually displayed another. The best example of this in the 2D HD world is 1080i; there are lots of 1080i channels, but good luck buying a new HDTV that is 1080i. 3D is a bit more complicated because it is almost never transmitted the way it is viewed. It is usually transmitted by packing both the left and right image into either a standard HD frame, or a jumbo frame that is twice the size of its 2D counterpart (for example, 3D Blu-ray is transmitted via HDMI in a 2205×1920 resolution). While all the latest 3DTVs use active shutter glasses to display the two frames sequentially, and not one of the other or side by side.




QUOTE
You need a 3-D Blu-ray player to view non frame compable signals, regardless of what illusions you have. The Non-frame compatible images give the best results over frame compatible in the real world.

You refer to "signals" but Blu-ray discs contain recorded data. This [/these] data is [/are] read. The codec can vary. The term "signal" is more appropriate for a radio frequency transmission. It's true that the common form of 3D TV terrestrial and satellite transmission is side by side. Using 1920x1080i25, you lose half the horizontal resolution of a 24fps movie broadcast at 25fps, but none of the vertical resolution (segmented progressive frame). With sport you would use interlaced which in 2D might be broadcast as 1920x1080i25 [or i30], and which in side by side 3D would then become (960 +960) x 1080i25 [or i30]. An important point is that the left and right images in use in these transmissions are unique; they are not mere pixel shifted transformations of each other.

QUOTE
Lastly in the control room the stereo images are converted into main and depth signals so that the depth controller can adjust the depth between cameras in a multiple camera production and to match the program content.

It is still early days in establishing 3D protocols for sport, such as the 2011 Wimbledon finals in 3D. I think what you are referring to are methods of monitoring the apparent 3D depth (by coarse instantaneous calculation) and giving instructions to camera operators by visual display or orally (or sending control signals to 3D cameras capable of changing toe in and/or inter-axial distance on the fly), or as last ditch methods, suppressing excessive 3D strength by manipulation of the picture content in the offending part of the picture. This is not to be confused with generating a 2D image plus simple depth.

I challenge you to direct us to any 3D video of real life sport that has been published in the format of 2D and simple depth. (I note that for image content in the foreground it would look particularly artificial.)

The only 2D + simple depth you are likely to find is with the cheap 3D simulators in domestic TV sets that convert 2D incoming video to an approximation of 3D. The algorithm attempts to find parts of the image that are likely to be in the foreground and does a pixel shift to the right, for that part of the image for delivery to the left eye; and and pixel shift to the left, for that part of the image for delivery to the right eye. It is amateur and unconvincing: a novelty. Also some unsophisticated 3D games may use this simple method.

Edited by MLXXX, 18 January 2012 - 12:03 AM.


#9 alanh

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Posted 03 January 2012 - 08:48 PM

MLXXX,
You can quote as many non industry connected sites you like, but they are not the source the real source is HDMI Standards organisation. Note there is an upgrade of the existing HDMI standard in the middle of the year.

Your link to Tom's harware does not mention HDMI nor does it mention Non-frame compatible 3-D as are all your other quotes. Similarly all of these quotes are for frame compatible systems.

The way HDMI sends the signals is significant. In a 3-D display the pair of images has to be stored in separate areas of RAM. Then the images are shown sequentially not side by side or one below the other.

So for a non-frame compatible signal, each packet is labelled and can be sent to the correct area of memory directly. For frame compatible signals the memory controller has to change the addressing to separate the left and right images to their respective areas of memory. The reading of left and then right memory data in turn is the same for all systems.

The articles you refer to do not go to the depth of the actual signal formatting, pin connections etc.

There are plenty of articles in true broadcaster magazines describing the need for a depth controller position in the production team. This is just as necessary as a camera control unit controller. Their job is to make the exposure and colouring of cameras to be identical regardless of the lighting. This position is required even though all cameras can automatically adjust their exposure and colour balance.

Sony make the depth processor in their professional product range.

AlanH

Edited by alanh, 03 January 2012 - 09:01 PM.


#10 MLXXX

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Posted 03 January 2012 - 09:50 PM

Where is your source of information to support the sentences I am highlighting in red? :-

* Non Frame compatible method. In this method the signals from the camera are combined into a 1920 x 1080p signal. This is identical to the standard Full HD signal. To display depth the distance between edges with in the image in the horizontal direction are measured. This produces a second 1920 x 1080p signal. When the Blu-ray player plays this MVC-MPEG-4 compressed signal it creates a pair of 1920 x 1080p images in its memory. The depth signal then is added to the read clock in the appropriate RAM image which moves it sideways.

I put it to you that those sentences are supposition or misinterpretation. And that they are not in accordance with reality.

To create genuine 3D video of real life, such as sport, two cameras a short inter-axial horizontal distance apart produce unique (though correlated) Left and Right video streams. To encode these to MPEG-4 MVC, one stream, such as the Left, can be selected as the main view. That would leave the Right image to be allocated to the supplementary view. The supplementary view is encoded to the same level of detail as the Left, not approximated with a simple depth map; albeit that the main view serves as a reference and reduces the additional bitrate required for the supplementary stream. That is the basic scheme. Anything else (monitoring and constraining or boosting of apparent strength of the 3D either live or in post-production) is tinkering at the edges. [EDIT: Yesterday I used a 3D camera to record some chicks (4 or 5 weeks old) repeatedly jumping up to a perch inside a bird cage. To get a good view into the cage the camera had to be very close. This has resulted in an AVI 3D file that is hard to watch. The 3D effect is too strong for my eyes, and for most people I would think. I will have to do some processing to bring back the strength of the 3D to something manageable. After that I will still have unique Left and Right views. It will not be 2D plus simple depth.]

If you bothered to watch a selection of paused 3D Blu-ray frames, you would discover that the differences between the Left and Right views are more than simple horizontal squashing stretching and displacement consistent with simple 2D + depth. There is unique content in the Left view that does not appear in the Right view, and vice versa. That is the nature of true stereoscopic 3D. It is what we see in nature. "2D + simple depth" would be a crude and unnatural approximation. It would, for example, be incapable of adequately conveying the wondrous 3D of James Cameron's Avatar.

_________

As an example of the problem of 3D stereoscopy and "occlusion", compare the brickwork visible behind the top right hand corner of the gravestone in the side by side views at http://en.wikipedia....avestone_3D.jpg The brickwork is quite different as between the Left and Right views. [N.B. The Left and Right views are interchanged to faciltate cross-eyed viewing.]

Try encoding that scene as 2D plus simple depth and see how inaccurate the reconstructed Left and Right views behind the gravestone become. Fortunately, 2D plus simple depth is not commonly used.

Edited by MLXXX, 04 January 2012 - 10:11 AM.


#11 hrh

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Posted 04 January 2012 - 12:53 AM

What was the question again?
And, has it been answered or just danced around?

#12 MLXXX

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Posted 04 January 2012 - 02:34 AM

What was the question again?
And, has it been answered or just danced around?

The question in the topic was What Does A 3d Blu-ray Player Do?

First off, a 3D Blu-ray player can decode the extra view in MPEG-4 MVC video, whereas other players may decode just the "core" 2D view and ignore the extra view required for 3D.

Next, when getting ready to play a Full HD 3D disc, the player tests the protocols of the display device connection. If the receiving device signals that it can handle the 3D "over under" format, the player will send the Left and Right images in Full HD in a double height frame via HDMI. The display will then extract the Left and Right views automatically and present them on the screen as 3D (e.g. for shutter glasses the screen will alternate quickly between the Left and Right views).

What if you are connecting a 3D Blu-ray player via HDMI to an old AVR that cannot handle double height frames, and feeding from the AVR to a Full HD 3D TV?
In this instance the Blu-ray player will output in squashed side by side mode (1920x1080). [It may even do this at 60 interlaced rather than 24 progressive.] So the horizontal resolution is halved to 960 for the Left view and 960 for the Right view. Now I'm not dead certain but I seem to recall reading that the 3D player will send a special HDMI code in this situation, so that the display will automatically recognise the 1920x1080 as squashed side by side, and extract and widen the Left and Right views automatically, i.e. no need to set side-by-side mode manually.


A lot of 3D on the net is disseminated in squashed side by side mode and to media players and Blu-ray players is indistinguishable from a 2D video protocol. There is no indicator in the header of the file for 3D. To play such a file as a media file on a Blu-ray player you can manually set side by side mode at the 3D TV. The TV will then split off and widen the two views and display them as 3D. [MPEG-4 MVC although it appears as a transport stream on a 3D Blu-ray disc is not a commonly available protocol on the net.] There are some other variants too such as squashed over under, and field alternation. These look like ordinary frames to the media player and can have the appropriate 3D mode manually selected at the display (assuming the display device can handle the particular 3D mode).

Edited by MLXXX, 04 January 2012 - 06:11 PM.


#13 Stux

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Posted 04 January 2012 - 02:18 PM

The simple answer is that a 3D Bluray player can decode and deliver both views from a 3D bluray disc at full resolution.

A 2D player can not.

Simple web video players do not decode both views from a full resolution 3D mvc file. Rather both views have been squashed into a traditional 2D file, and the TV is extracting the 3D views from the 2D video stream... but not at full resolution.

#14 hrh

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Posted 04 January 2012 - 03:35 PM

The question in the topic was What Does A 3d Blu-ray Player Do?

First off..
Next,...

On behalf of myself at least thanks for that.
It seems to have provided a reasonably concise and uncomplicated explanation.
I hope the OP has gained from it too.

I only wish so many other questions could have been answered as simply and relatively briefly whilst staying on topic.

#15 alanh

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Posted 04 January 2012 - 06:32 PM

MLXXX,
The MVC-MPEG-4 signals you are looking at are reconstructed and not in their encoded state. So the level of detail in both images will be identical because they come from main signal. The depth signal is not displayed at all because it just looks like a series of edges where there is close up detail. This is just like if you look at a Pr signal on its own, it is grey except for red and cyan patches where they are in the pictures. This is never shown on consumer equipment.

AlanH

#16 MLXXX

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Posted 04 January 2012 - 09:34 PM

MLXXX,
The MVC-MPEG-4 signals you are looking at are reconstructed and not in their encoded state. So the level of detail in both images will be identical because they come from main signal. The depth signal is not displayed at all because it just looks like a series of edges where there is close up detail. This is just like if you look at a Pr signal on its own, it is grey except for red and cyan patches where they are in the pictures. This is never shown on consumer equipment.

AlanH


Yes there is a detailed Left video image and a detailed Right video image. How the MPEG-4 MVC codec identifies correlations between the supplementary view and the main view and encodes similarities and differences is up to it. There is no classic "depth" signal. (This scheme differs from the classic 2D plus depth method where you superimpose a depth map for each frame for shifting pixels to the left or right, to generate Right and Left views.)

#17 alanh

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Posted 04 January 2012 - 10:23 PM

MLXXX,
Since you are looking at reconstructed images how can you say what you have as you cannot see the non main signal?
The non main signal does not contain similarities as these would duplicate the main signal. It is only the non common information which is encoded.

If the similarities are encoded in both signals then there would be the same requirements as for frame compatible images with the only exception that each image is identified in packets instead of combining them into a single signal. So for a pair of full HD signals the data rate for Stereoscopic vision is double that of 2-D.

AlanH

#18 MLXXX

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Posted 04 January 2012 - 11:20 PM

If the similarities are encoded in both signals then there would be the same requirements as for frame compatible images with the only exception that each image is identified in packets instead of combining them into a single signal. So for a pair of full HD signals the data rate for Stereoscopic vision is double that of 2-D.

No. If the far background is identical right down to the last pixel, then the dependant view for those far background parts of the frame can be encoded to simply point to and extract data from the main view by way of reference. Of course there is no need to repeat the data content when encoding the dependant view.

In another variation, the background may be largely similar but displaced so many pixels to the left in many parts. The encoder could cross reference to the main but add a motion vector. There would be a tidy up with relatively small corrections.

In another variation there may be parts of the dependant view with nil correlation with the main. Despite that they may correlate with past [or future, buffered] content in the dependant view, and could cross-reference.

In other words it is akin to normal MPEG-4 AVC encoding where part of a current frame can cross reference to parts of past or future frames. And there is use of prediction. There is the differerence that the dependent view can cross-reference to content encoded for the main view, a major efficiency.

How do I know these [basic] things? From reading high level descriptions of how MPEG-4 MVC encoding works for stereoscopic views.

How did I know about the output format of Blu-ray players? By reading descriptions of that format, provided by technical writers.

Your rejection of "unofficial" sources leaves you with very little to go on, other than trying to read and interpret technical standards some of which are only accessible by paying a fee. Also there is a big difference between what protocols are defined, and what protocols are in common use or actually implemented. 2D + simple depth is defined. However, it is not in common use for real life video.

Edited by MLXXX, 05 January 2012 - 12:46 AM.


#19 alanh

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Posted 05 January 2012 - 01:03 PM

MLXXX,
You obviously do not understand the difference between stereoscopic and true 3-D
You have no knowledge of the optics and the small angles involved in stereoscopic vision which is what these current "3-D" systems are.

Your technical writers are not those who are designing compression systems or those in TV station and production companies but others who claim to be technical writers on line. As I pointed out about HD guru.

You have not understood the article on sound processing used in radio stations so there is little point in continuing these discussions.

AlanH

#20 MLXXX

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Posted 05 January 2012 - 01:27 PM

The original version of this post did not address the individual points raised by alanh. On review, I have decided to respond to them.

MLXXX,
You obviously do not understand the difference between stereoscopic and true 3-D

I don't know what causes you to think that.

You have previously mentioned that stereoscopic 3-D is limited compared with real life 3-D. Of course it is. However for a viewer in a seat in a public cinema the viewing position for practical purposes is fixed. A single Left and a single Right view at the projection screen correlate reasonably closely with a real life 3D view from a fixed position. A difference is the difference in focus required in real life.

If you want to argue that cinema should strive to allow people to shift viewing position then what you demand is not met by conventional 2D cinema either. With 2D cinema you sit and you see through the window that the screen presents to you.

What the relevance is of discussing true 3-D is not quite clear. However it is clear that MPEG-4 MVC allows stereoscopic 2D to be encoded accurately, whereas 2D plus simple depth does not.


You have no knowledge of the optics and the small angles involved in stereoscopic vision which is what these current "3-D" systems are.

You have previously claimed that the approximation of 2D + simple depth is adequate but as the side by side picture I linked to of a gravestone illustrated, there are substantial differences in the background where occlusion is caused by a foreground object. In fact you need only walk down a street to observe the effect in real life. Or look at objects in your sitting room first with one eye closed, then with the other eye closed. Or watch a Blu-ray 3D video.

You have not supplied even one example of real life video encoded as 2D plus simple depth.


Your technical writers are not those who are designing compression systems or those in TV station and production companies but others who claim to be technical writers on line. As I pointed out about HD guru.

Their role is as technical journalists. HD Guru in particular wrote articles of a high standard and received favourable feedback from readers. Quite an achievement to receive consistent positive feedback.


You have not understood the article on sound processing used in radio stations so there is little point in continuing these discussions.

That's a bit rich. The article referred to "compression" used in DAB+ broadcasts in Australia i.e. amplitude limiting in different audio passbands; and to treble boost. There was nothing new in that article. As I have stated in another thread, no one should purchase the magazine in the hope of gaining enlightenment from that particular letter to the editor.

Edited by MLXXX, 06 January 2012 - 09:41 AM.


#21 MLXXX

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Posted 08 January 2012 - 08:10 PM

You have not supplied even one example of real life video encoded as 2D plus simple depth.



I haven't myself stumbled on a downloadable 2D plus depth video of real life, but I have found a simple animation video. The webpage is http://www.dimenco.eu/2dz/ The animation video file is called Dimenco_BigBuckBunny_2DZ_sample.s3d

It can be played on the latest version of Stereoscopic Player. I say "latest" as 2D plus depth was only added to that player a few days ago (from http://3dtv.at/Produ...History_en.aspx ):

Version 1.7.8 (January 5, 2012)
  • Added support for 2D+depth input format.
  • Added step reduction option for generic multi-viewer display viewing method.
  • Fixed sporadic player crashes.
Of course, anaglyph glasses, or a 3D display, would be required for viewing this simple animation in stereoscopic 3D.

I note that Stereoscopic Player has been able to play 3D MVC files since its version 1.6.9 of 1st March, 2011 so as to provide detailed and accurate sterescopic Left and Right images. Where the encoded sterescopic MVC appears as two separate m2ts files, suitable for a 3D Bluray, you can open them in Stereoscopic Player by choosing the "Open Left and Right File..." command, loading the base file as Left, and the dependant file as Right. The player will then launch its MVC decoder. On a 3D Blu-ray disc, these files are found in the STREAM folder, and there is normally a subfolder SSIF containing a file with the extension ssif, which combines the base and dependant files. Stereoscopic Player can also accept just the ssif file as 3D Full HD input.

This information will be a bit moot for most readers as standalone software for creating MVC encodings tends to be expensive. The main source of Full HD 3D for most people would be commercial Blu-ray movie discs, which would simply be played on a 3D player (or possibly on a Blu-ray pc drive with 3D player software, and appropriate graphics card).

Edited by MLXXX, 11 January 2012 - 11:35 PM.


#22 djfish31

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Posted 18 January 2012 - 02:40 PM

Hi all,

Just starting to get into the 3d, I have a samsung 51" 3d plasma and a ps3 i have been playing the 3d movies on the ps3.
Is it worth me going out and buying a dedicated 3d blu ray player and what would be the advantages?
Thanks in advance..

#23 com5984

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Posted 18 January 2012 - 05:11 PM

I just bought a new toshiba 3200 for 130 bucks, multi-region for both dvd and bluray. The pic quality for bluray is on par with my oppo, haven't tried 3D yet still waiting on TV.

#24 MLXXX

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Posted 18 January 2012 - 09:35 PM

Hi all,

Just starting to get into the 3d, I have a samsung 51" 3d plasma and a ps3 i have been playing the 3d movies on the ps3.
Is it worth me going out and buying a dedicated 3d blu ray player and what would be the advantages?
Thanks in advance..

I am assuming you have surround speakers, and an AVR to drive them.

Is the ps3 HDMI output going to an AVR (to extract high definition multi-channel sound)? Is the AVR then passing the 3D at full definition (rather than half width side by side mode) to the plasma TV?

If the ps3 can pass both the sound and 3D at full quality to the AVR, there does not seem to be a problem. (I'm not fully up to speed with the ps3 but I understand there have been many updates to its software/firmware.)

On the other hand with 3D Blu-ray players now getting cheaper you might find acquiring one worth the convenience of being able to play Blu-rays without tying up your pc.

#25 djfish31

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Posted 19 January 2012 - 10:04 AM

Thanks for that i have an older recierver that doesnt have HDMI so i go HDMI from the ps3 to the tv then optical back to the reciever.
i just want to make sure i am getting the best picture i can.