Why have a headache from 3D / Part 3 entanglement angles

Chicken Pfister prism, deflecting the light entering into her eyes. Also, similar experiments were carried out later with various animals - with chickens / hens, kittens / cats, monkeys, and so on. D. An interesting conclusion of these is that the human brain is much more adaptive than the brains of animals and man is capable of much more successfully adapt to the "impossible" image, even in comparison with monkeys.

Conclusion:
Professionals trained on a bad stereo, no longer experience severe discomfort from it, which leads to the deletion of the easily correctable errors in the mass releases of films. If a person shows poor stereo, then gradually decreases to experience discomfort, especially if the "train" binocular vision since childhood. Perhaps this explains the large number of "terrible" by the standards of Europeoids stereo, which is now mass produced and shown in China. As a result, China's domestic market, for example, most ready for new autostereoscopic devices, the image quality of which the first stage is bound to be imperfect.

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Algorithmic complexity
From the point of view of computer vision problem of determining the angle of entangled very nontrivial and interesting. It is interesting in the first place so that it is a very simple statement and, in contrast to many other areas - elementary to prepare a test sample. You just take some stereofilm, doing short simple script, which in every other scene reverses the angles and get an excellent test base of 1000 scenes for debugging their own algorithms.

And then the fun begins. If a person, especially to poor stereo nenatrenirovannogo determine confused angles is quite simple, then the program is not a trivial task. The man knows how things should look, and that is the closest, and that further, as it has "Psychometric" about what forms of furniture, which form the house, and so on. D. The program has no such knowledge and despite regular (over the last 40 years) triumphant about the next breakthrough in science, recognition of objects and, as a consequence, for example, robot vision still leave much to be desired. It should be understood that in order, to correctly identify entangled angles, robots must conditional on information from one camera to determine which is closer, and then what better than a man with two eyes
To solve various features can be used, for example, that the bottom is likely to be objects closer than the top of that foreground objects are generally convex, etc. But the problem is that all these features are extremely unreliable, and, ultimately, on our test sample of 1,000 scenes such methods will be wrong too often.

A more reliable approach is to analyze the motion. In modern films are practically no scenes without motion, with virtually any motion, we can determine with respect to m. N. regions "opening and closing" where one object occludes the other, and hence closer to a object.





In scientific language problem of determining the depth of objects on 2D video called "depth ordering" , and is easy to see by following the link in this field is being quite a lot of research. Looking ahead, I must say that their results still leave much to be desired. Of course, in the article, you will often see beautiful pictures, but if you look at the independent tests themselves or try to drive algorithms are available, for example, in the source code for MATLAB, you will disappointed with the quality of their work and the mass of errors.

Next, you need to solve a simpler problem definition of the apparent depth of the object on the stereo, or speaking in scientific language - the task of building disparity maps. Algorithms for constructing improved disparity maps for about 30 years, but there is also still a lot of problems.



For example, if you go to this link , you will see a comparative analysis of algorithms for constructing about 160 cards disparities created over the past 15 years . Sort the plate and look at the results of the best algorithms. That rough edges? Pieces of objects or even objects lose? What you say! ) And then find relevant articles for the best algorithms and see how long they work. One frame. Now count how many years (or a supercomputer) is required to handle these algorithms with the entire movie. Who are too lazy, there in the worst case operating hours per frame, and as a result, decades of secondary computers to process the entire movie. Exactly this explains the fact that even just work on the definition of irregular angles today is not so much.

They were, as you might imagine, the bad news. Where is the good? Patience, gentlemen. Some good news. Firstly, to say that the scene confused perspectives we generally do not need all the objects in the scene. Suffice it to some one object (or sometimes even one boundary) reliably ranked their depth and out of traffic, and from the disparity map. This is a serious simplification, although we still need to build and the one and another card for the entire frame. Second, in recent years, increases exponentially the speed of the GPU and many video processing algorithms, which until recently were too slow for practical use, acquire a second life. Or first, if we assume that such is not the use of the articles and the use of practical problems in real life. And finally, thirdly, there are ways to effectively accelerate existing algorithms, if we are talking about the processing of the entire movie.

I must say that over the past 5 years, under the guidance of the author was made two serious attempts to solve this problem, and a second attempt is possible (with reservations) considered successful in the sense that built practically on the speed of the algorithm, which is an acceptable number of errors makes it possible to find Entangled angles in real films.

Also worth noting is that in the process of working on the algorithm began to be a scene in which individual objects (usually special effects) were imposed on the "wrong" depth, for example, deeper objects to which they overlap. From the point of view of the opening and closing regions in time and depth is also an impossible situation. It is impossible from the viewpoint of the brain. We see that the object is closer, but binocular vision tells us that it is farther away. This is a very unpleasant situation, the diagnosis is complicated by the fact that a large part of the scene is the "right", and only a single object is incorrect. Nevertheless, it is necessary to detect such things. Known, for example, the case where one low-budget Hollywood film in general, all the special effects imposed confusing angles. He went to the theaters (the poor audience!), But in 3D Blu-ray it was never released (maybe not to disgrace, and maybe just realized that additional charges will not be).

Conclusion:
As strange as it sounds to those who are not interested in computer vision, but the problem of determining the angle of entangled today is not completely solved. The main difficulty in determining the safe boundaries of objects on the motion and depth, as well as in the processing of scenes where there is no movement. However, for various reasons, even now an opportunity to create the first practical algorithms of this kind. Practical - is at an acceptable rate allowing to process the entire movie.

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How often confused perspectives in life
And now - the most interesting results of the analysis of 105 films for scenes with reversed angles (Channel Mismatch, abbreviated CM). Due to the speed of our algorithm we have the opportunity to check the many tens of movies. It's still hard, but it was possible! In fact, our team had to check all the films that went on Blu-ray, which is specified in the budget IMDB.com, ie all more or less decent movies. Following results were obtained:

Movie name Release year Budget, $ M Scenes with CM Total CM duration, sec Film duration, sec CM percentage

The Child's Eye Child's eye 2010 $ 4.50 15 57, 5 5823 0, 987%

The Nutcracker in 3D Nutcracker 2010 $ 90 9 28, 9 6480 0, 447%

3D Sex and Zen: Extreme Ecstasy Sex and Zen 2011 $ 2.5 9 23, 1 6775 0, 341%

Spy Kids 3D - Game Over Spy Kids 3-D: Game Over 2003 $ 39 5 10, 3 5063 0, 203%

Hugo Hugo 2011 $ 170 2 10, 2 7581 0, 135%

Sharks 3D Sharks 3D 2004 $ 5 1 8, 9 3073 0, 290%

Saw 3D Saw 3D 2010 $ 20 3 6, 7 5405 0, 123%

The Last Airbender Airbender 2010 $ 150 2 6, 6 6193 0, 106%

Dark Country Dusk 3D 2009 $ 4 4 5, 7 5287 0, 109%

Creature from the Black Lagoon The Making of the Black Lagoon 1954 2 5, 4 4746 0, 114%

Ghost Rider: Spirit of Vengeance Ghost Rider 2 2012 $ 57 1 4, 6 5732 0, 081%

Stalingrad Stalingrad 2013 $ 30 1 4 3 7849 0, 055%

Avatar Avatar 2009 $ 237 1 3, 3 9702 0, 034%

Spy Kids: All the Time in the World in 4D Spy Kids 4D 2011 $ 27 1 2, 9 5265 0, 056%

Harry Potter and the Deathly Hallows: Part 2 Harry Potter and the Deathly Hallows: Part II 2011 $ 125 1 2, 9 7827 0, 037%

The Chronicles of Narnia: The Voyage of the Dawn Treader The Chronicles of Narnia: The Voyage of the Dawn 2010 $ 155 1 2, 6 6761 0, 038%

Conan the Barbarian Conan the Barbarian 2011 $ 70 1 1, 2 6742 0, 017%

Step Up 3D Step Up 3D 2010 $ 30 1 0, 9 6431 0, 014%

Clash of the Titans Clash of the Titans 2010 $ 125 1 0, 7 6306 0, 011%

Drive Angry Drive Angry 2010 $ 50 1 0, 7 6271 0, 011%

Bait Tsunami 3D 2012 AUD 30M 1 0, 6 5588 0, 010%

A Very Harold & Kumar 3D Christmas Killer Harold & Kumar Christmas 2011 $ 19 1 0, 5 5379 0, 009%

The Three Musketeers Musketeers 2011 $ 75 1 0, 5 6632 0, 008% It is also typical that films of 23 in 13 is only one stage, and at 12 - at this stage the length of less than 5 seconds, and at 6 - less than one second. Actually, exactly why the error is not noticed. In general we can say that if you are watching a movie, released on Blu-ray, with a probability of at least 21, 9% of the film will be at least one scene with reversed angles. As a minimum, as now presently metric transmits about 5% scenes. This is a fee for a reasonable speed. Nevertheless, it is now possible to diagnose and fix problems conditionally 95%. It is interesting to see how varied the percentage of films containing entangled angles over the years, there is quite indicative of statistics. These are the same as in the previous table, but additionally take into account how many movies the same year a whole. Release year Number of movies Movies with CM Movies with CM, percentage Scenes with CM 1954-2000 6 1 16, 7% 2 2001-2009 15 4 26, 7% 11 2010 17 7 41, 2% 32 2011 24 8 33, 3% 17 2012 20 2 10, 0% 2 2013 21 1 4, 8% 1 2014 2 0 0, 0% 0 It is clearly seen that the conditional 20 films released before 2010 entangled angles met respectively 16% and 26% of the films. In 2010, immediately after the release of Avatar - has been a surge of 41% 17 films contain scenes with reversed angles. In 2011, 24 have only 33%, but in 2012 of 21 - only 4.8%. The Ones. defect rate in this area was sharply reduced, and the data is quite statistically significant. Statistics for 2014 are still too small to draw conclusions, but most likely it can be expected that the percentage will be reduced even marriage. Anticipating questions, once again, I note that checked releases issued on Blu-ray, which usually come with a fairly noticeable delay also runs themselves, despite the radical acceleration metrics still take considerable time, so we get the data with a delay. Nevertheless, the observed trend is encouraging. Also by the author over the past three years to carry out technical analysis stereofilms "Moscow International Film Festival 3D-stereo". The Ones. The Ones. The Ones.   3D videos 3DTV quality assessment confused perspectives  Five things that can be printed on 3D-printer. Part №3: the first book printed on 3D-printer?  Microsoft celebrates its 40th anniversary