Introduction to Match Moving
This project is a detailed report into camera tracking and how it’s techniques and methods hold up over two separate programs; Blender 2.69 and After Effects CS6 which will be looked into as a ‘practise-as-research’ method where an accompanied video will state the results of the experiement. This research will give insight into the programs effectiveness and techniques it has gone through in order to carry out the process of camera tracking.
The argument will be based on how each program deals with the process of match moving which will be for or against. A analytical and reflective report will be given at each stage of the process to help distinguish a programs efficiency.
The process inside these programs will be accompanied by a supporting lit review into key terms involved in matchmoving. This will help with in communicating process and provide the experiment with answers into why a program may be behaving in a certain way.
After both programs have been tested a conclusion will be made into the programs efficiency and ability within matchmoving. A conclusion will also state if the program was user friendly or not and whether the asphetics of the program gave it better credibility. One program will be ruled out as the least effective program for camera tracking. An over view of it’s need in industry may help support a program and give clarity towards its results.
Match Moving is a process where an individual or team hopes to map out a piece of footage in order to blend elements of VFX into it. It relies on a sometimes gruelling process where a user must follow a frame by frame process in order to map out objects, movement and other points of reference. The process is extremely long; usually needing a number of people taking part at different stages. Ridley Scott’s took on around ten people to super impose a Colosseum onto a built set to bring one of the largest match moving projects for Gladiator in the year 2000.
The process was huge; the team had to delicately create a three quarter animated arena that would be placed onto the built set. The set was only so high so the team also had to extend the arena adding more floors and a roof: One shot in particular would prove more difficult than the rest. In the scene where Maximus comes out into the coliseum with the gladiators: This shows a full 360 degree camera rotation around the actors walking out into the arena. This provides an excellent display of match moving using both 2D and 3D VFX and became an incredible accomplishment. Hopefully through this task you will begin to understand why this process was so difficult.
In order for an efficient report I have taken on a number of sources of literature on the subject of matchmoving. It will help to better understand the subject and leave room for the argument of the essay.
Two books were used that gave the study of matchmoving to the reader. It would include the process a matchmoving programs goes through as well as showing what it is made up from and what it takes to be a match mover:
“Experienced matchmovers look at effects shots with a different eye than other visual effects artists because their job in unique”
Matchmoving: The Invicible Art of Camera talks on how matchmoving is an invisible art but explains it’s importance:
“If you’ve done right, no one should ever know you’ve done your job at all.”
This indicates that the job of a matchmover is suttle although it goes on to prove a long process full of a mixture of complex systems.
Match Moving Basics from Lit Review
Match moving is a technique of imposing VFX onto recorded footage. It relies on built-in algorithms that communicates with a computer to build a digitalised environment that will replicate movement through a scene / location. The digital environment is built by placing markers that will establish; placement, movement and location of objects, all information that will determine a 3D world where elements of VFX are free to roam. The idea is to provide enough dimensional information within a scene using tracking markers, these results are then processed and made to sit along an axis which can then be replicated inside a program which has a similar axis function. Accurate information relies on marked information that is true and does not move or disappear out of a scene a scene. ‘Slipping’ is a term used when a tracking marker has lost it’s point of reference and begins to slide and jerk around the screen. This is inaccurate data and is essentially telling the program that this area is moving. Slipping can occur when a marker is having trouble identifying one area from another and begins to move from each.
Tracking markers have a number of ways they use to stick to areas. They have three points within the marker which will help with keeping a marker on track. Tracking markers are seen as small boxes which have three different components: centre point, pattern area and search area. The centre point is usually a crosshair at the centre of your marker which identifies the tracking point. It is ideal to place your centre point on an area that has a distinctive colour difference to other areas and this is due to the other parts of a tracking marker. The pattern areas is the smaller square outside of the centre point which records the data around the centre point which is why you want a tracking marker on area which stands out, as an area which doesn’t will cause the marker to slip. Which means that all things like the shape and colour of a situated area in and around are all vital points to tracking. You may want to track an area based on the specular difference of a point or the symmetry / pattern of detail inside the pattern area. Of course you may be thinking what happens if the camera is moving then wouldn’t the perspective of the area inside the pattern area change and the answer is yes and which is why the third part being the ‘search area’ is made to look around for possible areas which may move or come into shot. This art is to prepare the tracking mark for the next frame and change in perspective. All this makes for a more diverse marker as it is taking into account a reference point and the outer information which will help the marker from moving.
The idea is to mark out a 3D world from a 2D projection: Specific details like how much depth is in the shot, how much movement is through the scene and motion blur will coordinate the information of a scene from the information of the camera which in essential. Before going into the information for the camera it would be good to mention the practicality of a camera and lens to better understand projection as a topic and why a program needs to convert the camera information. This is all due to how a camera records information and how both the camera and lens records information. Firstly when a camera records data it prints it onto a 2D plate which means all 3D perspective are changed an altered. Things from a far can look closer than they really are and shape and size can look different. It can also depend on the angle of a shot as things that give an idea of depth and layout could be hidden behind other objects making it harder to mark out points that will give a program an idea of perspective as every axis needs a clear example. Match moving can be easily done when the camera is static or panning this is due to a distortion known as parallax. This is a shift is perspective where the viewers point of view can alter when the camera moves along the axis. This can cause a subject in the fore ground to appear as if it is moving and can alter the size or shape. Parallax will affect match moving as it is a false perspective This will tell the program the distance and movement and the more static and bold an area is will mean a much easier match move process. The areas that stay throughout shot and mark out a great amount of information in the desired grounds (fore,mid, back) will provide better information for the match moving program. All this information is calculated and will map out a 3D environment which will be ready for animators to work inside. Exposure; depth of field; shutter angle and movement are all things a match moving program wishes to achieve and is done by a calculated collection of accurate markers. The computer is not clever and needs to be shown exactly what it is you are trying to match move. It is no good placing markers on a tree blowing in the wind that will disappear off from scene, as the computer is trying to map a 3D environment and needs static areas. The world does not shake and move before you eyes, it is still and mostly tangible. A 3D environment needs this same believe. A viewer needs to feel that a 3D modle is actually moving through a scene in a correct fashion. Physics; gravity; these are the type of things that brings VFX to life.
Tracking is the bones of match moving and is the process to achieve accurate information for a match moving programme. A programme can not do this solely on it’s own and needs a watchful eye as well as an immense amount of patience. There are two types of tracking known as Automatic and Interactive tracking; automatic being a computers attempt to track a scene based on a framed shape (most automatic tracking relies on the areas around a tracking marker as well as the point of reference), and interactive is the slow frame by frame tracking process most of us would have endured. This is slow but the human eye can quickly distinguish between a blue pole and a blue sky where as the computer will face problems. Professional level motion tracking is usually achieved using a combination of interactive and automatic techniques. Automatic tracking relies on computer algorithms to identify and track. The advantage of this is an automatic track can produce more points of reference than the human eye. Although some references like motion and motion blur can create problems as the quality of this tracking will depend entirely on the computers algorithm and areas of repetitive subject matter will confuse a program i.e. blue poles blue skies. The advantage of interactive tracking is that a human can quickly distinguish between one area from another and has no problem with fast motion shots and motion blur. The disadvantage is that the user will make small errors as they follow objects through a scene which can lead to what is known as ‘drift’.
Match Moving History
The US Defence Department first created the concept of tracking systems from the missile guidance chips found in missiles.
with a missile guidance system which gave birth to motiontracking. This tracking system would be used to create motion control camera which were big mecanical devices that replicated an exact camera move from the other (first used in Star Wars.)
Optical composting was the first method of superimposing other images onto original footage. By using an optical printer it would allow a number of separate film strips to be rephotographed and combined onto a single layer of film. The process was time consuming with virtually no room for error. The film strips would need to be lined up Dykstaflex was the first motion control camer making dynamic camera moves 1982 Star trek wrath of Kon the first visual effects shot made inside a computer for a motion picture The stain glass man was the first computerised character (best visual effecs). Matchmoving would come into the industry when Jurassic Park made the first attempts of composting and matchmoving vfx instead of relying on the work of special effects.
After this process was made it brought infinite possibilities to the screen.
After effects was created by Company of Science and Art, USA. It was originally brought out for its skill in 2D and 3D composting and special effects before turning to other demands inside the industry. The program is available to Apple mac. After the 1993 release of After Effects the project was sold to
This program was made in The Netherlands in 1988 and became the countries greatest company to work with 3D animation.In 1995 it was rewritten and was transformed into the Blender that users know it for. in 2000 the company began to take money from investors in the hopes to make it a free program to users. Unfortunately two years later a major sponsor pulled out which colapsed the company. 2002 Nan came back to the company and began a quest towards free blender who took on a 100,000 Euro sponspor deal world wide. Its large community and supporters managed to revap the company and get it going once more. 2005 saw the introduction of an Open Movie called “Elephants Dream”. From the succession of this open move the company was able to tread forward and give the introduction to the Blender institute in 2007 and began to make progressions towards animated films and computer games.
In this next part we go over to Fali Mistry who has conducted a series of tests which he thinks should prove one programs efficiency over the other. The Youtube link bellow will take you to this 20 minutes video:
What was found out by the methodology part is that both of these programs have differences in terms of what they can offer. Blender being the stronger program for matchmoving with it’s precise manual tracking system the camera was able to follow points from the footage even when they had blown out and gone out of focus.
After Effects being the more speedy of the two programs could effectively track scenes with enough markers to begin compositing but failed to bring an appropriate solve rating. After Effects also had a visually pleasing design; it was user friendly with out menues that were hidden or hard to locate.
Blender showed an incredible skill at solving the camera with a result of 0.226 it was a clear accomplished program in this debate. The time it took was long and taking forty minutes for a sixty second shot although matchmoving is a legthy and delicate process this may be overlooked.
The two experiments got there results from the recording of a Blackmagic film camera and had three different experiments that would test each program.
Problems can occur n matchmoving when tracking with dslrs or camera with little dynamic range. The Black Camera is a digital cinema camera so we know that any problems encountered where down to the program it self.
Both programs had trouble with reading a pebled floor where each program would skip out and give a bad solve rating. We know that this could be done because of the movement in camera. The motion blur generated is a distinctive confusion to the objects that are in shot. Once an object is blurred the camera recongnises it at something else.
What was found is that both programs had trouble with the floor scene as motion blur and little definitive contrast between areas made the job difficult. Blender can quickly asses camera trickery from motion and this is by it’s camera plug-in system. The system allows the user to enter frame rate and sensor size which can indicate the effect of the shot, i.e. the increased speed of a high frame rate.
In this discussion element we will weigh up each of the programs and try to understand a conclusion based on the findings. The discussion will raise an argument for either program before going onto a conclusion.
The report argues that either program have little evidence of matchmoving in industry which makes either of these programs unusual choices for professional standard. With that being said it should be seen as the importance to all people and not just the pros.
After Effects has add-ons like Voodoo that can make it’s matchmoving attempts more efficient where Blender does not. Blender does not need an add-on because its ability to camera track and match move is already very good. In the film Tears of Steel we see the first ever feature distinctively by Blender. The movie proves that a production team is happy with the standard of the projegram; program efficientcy and time management would have all been taken into account and this grants Blender with a strong possition in the matchmoving world.
Blender is a completely free program meaning anyone can get hold of it which makes it the more accessible out of the two.
After Effects has a number of things that it is could add and can work well with editting programs and effects programs it can work with and has files that can be shared across programs with out the need of converting.
The thing that is apparent is that After Effects is it is a program used in industry; it is a program used my editors, compositors and vfs artists. In the new film Iron Man 3 After Effects was used because of its ability fast render and preview settings, it was also used to create a number of HUD’s from inside the Iron Man suit.
After affects is not a predominantly known 3D matchmoving program for industry and this could explain its results. After Effects was known more for it’s skills in 2D work and it was only until the industry became demanding in matchmoving when the product began to upgrade. Now a days you can download plug-ins to help with the new advancements in film / video but is that to say the product is creditable for this report and does it make it the better program for not specifying in matchmoving in the first place?
Products like Boujou and V5 have been running in industry and provided good results with Boujou winning an Emmy Award for best product it doesn’t give Blender or After Effects a chance in the industry exept for the movie Tears of Steel.
Blender has shown great ability with it’s manual focus system. It has provided a better outcome that the After Effects program but Blender is a free program which in other words it hasn’t got the demands of a competitive industry as it clearly in it’s own league. The fact that it isn’t a widely used program in industry has given it freedom to develop in the ways that it wants to. In other words Blender has made adaptations to what it wants to develop and hasn’t sprung to the needs of a number of factors in VFX like After Effects has.
It was able to translate the camera setting for the footage before any settings had been entered meaning that it is a greatly used and thought out program for match moving where After Effects did not have simplified options.
This conclusion is based on all findings it will conclude the hopes of the abstract and give way to a program being the better program for the task of camera tracking.
Firstly, matchmoving is a program made up of complex calculations and devices. It is a delicate procedure that needs the work of a person and automated systems. I conclude that Blender 2.69 is the better program all in all. It is an accessible program giving it a better result that After Effects: Both professional and student can get hold of the program and being to work with it. It can export targa files meaning it can quickly connect to texturing programs making it an easy program to introduce into a VFX pipeline.
It has both automatic and manual tracking systems making it the more versatile program; it can quickly cater for the needs of a 2d and 3d artist. The tracking marker inside blender has the three working areas found inside the lit review’s (pattern area, search area and centre point) meaning that the process of tracking is made easier. The user has more control and a better understanding of points based on the marker.
After Efects may seem like the better looking program but that is because things are simplified and in this topic simplicity is not a good thing. Blender is complex because matchmoving in its self is complex and needs a great deal of options and setting to maintain a good practice for new projects.
Matchmoving is relatively new in the industry which means that progressions will come fast and having Blender being the more complex of the two indicates that it is more prepared for these advancements where as After Effects is already so large that in needs to rely on the use of add-ons.
After Effects seamed to be the better program at the start as it had a quick process of calibrating the camera. A fast calibration is all well and good but in reality shows that there is less going on inside the program. The program calibrates fast because the process is not a delicate job like manual tracking.
The solve results prove that After Effects inherits a bad projection and from our findings we understand that this is important, it is important when being passed on to other members of a vfx team to not have a false perspective that makes there work unbelievable.
After Effects is idea for the student and the professional as it is integrated into a number of duties within vfx where as Blender has a main focus toward 3D modeling, texturing and matchmoving.
It’s ability of this process is seen by the film it has produced and acts as a strong tool for a vfx person or persons to get into. There the entire process can be made start to finish which grants it an important calling card for vfx.
Blender is able to give the user complete freedom when it comes to this task. With an accessible composting and modeling function this is little the matchmover needs outside Blender. It doesn’t need to rely on outside sources or add-ons making it cost effective and keeping the time it takes for production fast.
After Effects failed at placing tracking markers at a distance which means a film maker may be restricted in what he / her can or cant film. Where as Blender can virtually tackle any shot that is thrown at it.
After Effects also failed to track areas with no depth or perception of location. The struggle it had at tracking a pebbled floor shows that the program again is a bad choice for a matchmover.
After Effects also had problems when a user decides to click off of the tracking sequence meaning the process would have to be done again. This also gives the impression that it is not always time efficient.
The aesthetics of After Effects were pleasing to start with but the apparent demand for techniques and process proves that it needs a more in-depth layout with more options and panels; something that Blender has.
The complex and endless options with Blender has been handle with a number of side windows a user can pull up meaning that a matchmover of vfx artists can see there production in a number of ways simultaneously thus giving the program a distinct advantage.
When the matchmove took place there was a wave bar that would show the movement of each new tracking marker that was introduced which gave the viewer insight toward the results before the calibration had taken place.
Blender could follow the motion of the camera from a single track which made the mannual tracking system easier to use as when the user gets lost in to how the camera moves a red and blue line behind a marker would show in which way the camera was behaving.
Blender is definitely the more advance program seeing the development of Blender 2.69 shortly after the predecessor it is a modern device that is quickly suiting itself to the demands of the industry and has little else to focus on but 3d modeling, texturing, animation and camera tracking.
It is a more enjoyable program to use because of these advancements and freedom it gives to a user. It is not a flashy or even attractive program as it has turned its resources to computer power. There is a feeling when using Blender that it is has a capability of anything, despite knowing what it is or not it can do.
Blender was the best program for the hopes of matchmoving based on this research. It has proven to hold up against a competitor and to fair well in the industry. In one way or another it has ticked the hopes and aims of this research document and has proven to be the better program.
MATCH MOVING JOBS
http://getinmedia.com/careers/match-mover http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.84.1695 http://en.wikipedia.org/wiki/Match_moving http://www.vfxwages.org/designations.php http://www.makutavfx.com/jobs/matchmove/
https://www.google.co.uk/#q=Aaron+Singer+real+steel http://www.imdb.com/filmosearch?role=nm1234381&page=2&sort=year,desc&explore=title_type https://www.google.co.uk/#q=famous+match+movers http://www.skillset.org/animation/careers/3D_computer/article_4930_1.asp
http://home.earthlink.net/~kevincarney/UCLAext/Matchmove/TrackingHistory.html http://books.google.co.uk/books?id=hE7vlxVJwq4C&pg=PT7&lpg=PT7&dq=1970s+motion+control&source=bl&ots=ZOc9fsAp1t&sig=dedcVirWSP_CnLeanclTHWrIVqg&hl=en&sa=X&ei=lEFBU5GiEZOUhQfzt4GYCA&ved=0CEoQ6AEwBA#v=onepage&q=1970s%20motion%20control&f=false https://www.youtube.com/watch?v=xWJCxxKuTOw