Free Viewpoint Television

FTV allows the viewer to control the viewpoint and generate new views of a dynamic scene. This means the focus of attention can be controlled by viewers rather than the director or film maker. However this could ruin dramatic suspense caused by not being able to see the whole picture.

Professor Masayuki Tonimoto, who is a researcher in Japan has been promoting the use of Free Viewpoint Television with his technique of Ray Space Representation. Which is a development of Paul Debevec's 3D image Modelling and rendering techniques.

"This method allows it to render virtual views from arbitrary positions without any geometry information. Furthermore the generated image is photo-realistic."

However this is not the only way to create FTV.

How is it created?

1. Firstly cameras are placed around a subject, be it in a studio or a sports stadium.
2. The data from each of the cameras is the collated into a single codec, none as MVV (Multiview Video) which is then compressed so that it can be sent to the viewing device.
3. The users viewing device then uses the codec to access the relevant views so that new views can interpolated.
4. The new footage (which is a mixture of original footage and interpolated images) is then viewed on either a 2D or 3D display.

I believe that this form of viewing television will break into the mainstream, as i don't think it is suitable for viewing or capturing Drama or soaps. However i do see it being used to capture and view live events, such as; Sporting coverage or Music concerts. It could also find it's way into CCTV.

How bullet time was created in the Matrix

John Gaeta used a mixture of techniques to create the final product that is "Bullet time".

• Firstly each of the "bullet-time" sequences were filmed in a Studio in Australia using Green Screens

• The object (usually an actor) was then surrounded by an array of Still and motion cameras. this is the technique developed by Tim Macmillan. Each still camera took a single frame, either at the same moment or in sequential order. This depended on the desired effect. The Motion cameras were used to record the moments leading up to and after the "bullet time" moment, to give fluidity when moving in and out of the effect.

• Image Interpolation was also used to create extra frames so that they could slow down and speed up the action or the speed in which they panned round an object. This was so that they could have more control over how they edited the footage, while maintaining a high level of quality.

• To create the background to the scenes, they used Paul Debevec's technique of 3D image Modelling and Rendering. They did this by taking photos of the locations they wanted to use, For example the Rooftop locations of Sydney, Australia.

The Finished Product....

http://www.youtube.com/watch?v=vXAXyuShGUo&feature=related

Paul Debevec

Debevec was a researcher in Computer Graphics at the University of Southern California. He is Known for his work in high Dynamic range imaging and [more importantly to "bullet-time"] Image-based Modelling and Rendering.

In 1996, his research thesis was in Photogrammetry. This is where the 3D shape of an object could be collected from a group of stills taken from different angles. This lead to him embarking on a task in 1997 where he created a "Bullet-time" style flyby of UC Berkeley's famous Campanile tower.

http://www.youtube.com/watch?v=RPhGEiM_6lM

This was created by firstly taking pictures of the tower and the surrounding area from all sorts of angles. These were then in-putted into Debevec's Image Rendering software. This then created a 3D model which was then rendered and added to real video footage.

Many of the team that created the Campanile film went on to work on the matrix film, including Paul Debevec himself. this technique was used to create the rooftop backgrounds of many of the "bullet-time" scenes.

http://www.youtube.com/watch?v=WhxbYTMNMxo&feature=related

John Gaeta was quoted saying...

"Once I saw Debevec's movie, I knew that was the path"

Michel Gondry

Michel is a French film-maker who is noted for his innovative visual style. He began by producing music videos for his band 'Oui Oui', this then caught the attention of the artist Bjork and he was ask to direct many of her videos. This included 'Army of me' which used the techniques which were a predecessor to "bullet time"

http://www.youtube.com/watch?v=LyEJxzQM24Q

This technique is called View morphing, where you set a single camera around a static object and then morph the two together. Image morphing techniques can generate compelling 2D transitions between images. This works on the same principles Image Interpolation works on the matrix films by creating more frames between the ones you were able to capture.

Michel also used this view morphing in the 1998 Smirnoff Vodka advert.

http://www.youtube.com/watch?v=1vj4jppqwkw&feature=PlayList&p=5FE358E3F43BADBC&playnext_from=PL&playnext=1&index=52

This is where it is believed the whole idea for "Bullet time" came from. In the advert there are many instances where the technique is used. the most notable is at the beginning where the man jumps through the air and time appears to stop.

By the this time I believe Michel had moved on to using more than one camera in his set up, though still using the technique of View Morphing.

Tim Macmillan

The inventor of the time slicing technique of using Multiple cameras on a single rig. The first was devised in 1980 when he was in University and wanted to try and find how to take a photo of an object from different angles at the same instant in time.

His first "camera" consisted of;

• A length of 16mm film negative
• Above this he placed clear perspex spacers in order to give focal length
• Above the spacers he placed a length of opaque cinematic 16mm tape (with a pin hole drilled into each frame)
• A simple shutter was then placed over as a way of exposing the tape.

The result was a perpendicular tracking shot through space and time. A PARADOX!Since this rudimentary and low cost way of getting the desired effect, he has since developed his rigs. These now consist of an array of Still and motion cameras, which can be set in virtually any formation to get the desired effect. Macmillan's favourite being;

• Linear, which is where all the cameras track across the scene, providing a nice way of revealing elements over the duration of the scene.

http://www.youtube.com/watch?v=OZZy-ujf528

• Converged Linear, which provides a perfect way of spanning large areas, going big on the camera move whilst fixating on a certain points of action.

http://www.youtube.com/watch?v=KGBk9Wxxjqw

• Curved, this provides the greatest amount of rotation around a subject, a-la Matrix style

http://www.youtube.com/watch?v=TUBvt98uTTQ

Each of these video clips are work by Timeslicefilms, which was founded by Tim Macmillan. They are currently the leading production company that deal with "Bullet Time" capturing techniques.

http://www.timeslicefilms.com/#1

The Matrix

'The Matrix' (1999, dir. Larry and Andy Wachowski) was where the term 'Bullet time' was really made famous and where the way the concept was significantly developed.
'The Matrix' is a 1999 science fiction-action film starring Keanu Reeves, Lawrence Fishburne, Carrie-anne Moss, Joe Pantoliano and Hugo Weaving. It was released on March 31, 1999 in the USA and was the first installment in a very succesfull trilogy. It was Distrubted by Warner Bros and made a Gross Revenue 0f $463,517,383 from a Budget of $65million.

Plot Summary:

Thomas A. Anderson is a man living to lives, by day a boring computer techie and by night a computer hacker known as Neo. Neo had always questioned his own reality however the truth was far beyond his imagination. He then learns that he is being tracked by the police and is then contacted by a legendary hacker known a Morpheus, eho then awakens him to the real world.

Visual Effects

The Visual Effect Supervisor of 'the Matrix' was John Gaeta, who started the Research and testing for the film in 1996, while also working on the film 'What Dreams may come'(1998) which won an Oscar for it's visual effects. He Also won a BAFTA and an Academy Award for his work on the first Matrix film, along with various Visual effect Awards for the other films in the trilogy.
In 2000, after inital success of the original 'Matrix' film, Gaeta was asked to become the senior Visual effect Suppervisor on the remaining films in the trilogy, which were to all be filmed in a new multi-million, custom built, effects complex called ESC. The centerpieces to these films were to be terms coined by Gaeta, 'Virtual Cinematography' and Virtual effect'.These are basically umbrella terms for cinematographic techniques performed in a computer graphics enviroment.
In fully synthetic scenes of the Matrix sequels, all aspects including; principal actors, elaborate performances, dynamic events and scenery were all computer generated through a process of "image based" rendering technigues. This process is usually anologous with virtual reality and not film making.

More History

There have been many times in history where the concept of bullet time has been used.

In the late 1960's the concept was used frequently in cel animation. For examle in the title sequence of 'Speed Racer', the character is seen jumping out his car, it then pauses and the view point pans round in a 90 degree arc around the subject.

http://www.youtube.com/watch?v=_YTq7AJm_GI

The first music video to use the concept was 'Army of me' Bjork which was directed by Michel Gondry. It occurs 37secs into the music video and shows the girl driving the truck from dead on, the point of view changes profile shot via 90 degree arc around the subject.

http://www.youtube.com/watch?v=BeAZ9DQZFz8

Michel Gondry also used the concept the music video 'like a rolling stone' Rolling stones, here he has taken pictures from different POV's of the same subject frozen in time.

http://www.youtube.com/watch?v=dCz8-1RPJF4

Eadweard Muybridge

He was an English Photographer who used multiple cameras to capture motion. In 1872 he was hired by Leland Stanford, the governor of California, to prove the assertion of "unsupported transit". This was whether all four of a horses legs left the ground at the same time, whilst galloping. Muybridge was able to prove that they did all leave the ground with a single negative, however not as previously thought. They did not leave the ground out stretched as in the paintings, but whilst tucked under the body of the horse.

http://www.youtube.com/watch?v=Q8X0sHS0g8A

Muybridge was able to capture this negative through the use of multiple stills cameras, which were lined up along the edge of the a race track. Each camera was then actuated by a taut string that was stretched across the race track and attached to the shutter. This was so when the horse went past it would tug on the string and the film would be exposed.

After Eadweard went on to take photos at the University of Pennsylvania. These pictures generally involved the study of people and true human form. Here he used a bank of cameras which usually surrounded a subject/s so that he could study them different POV's.

http://www.youtube.com/watch?v=PjVaWaHCBxI

Eadweard also invented the Zooproxiscope, which projected images from a rotating glass disk in quick succession this gave the impression of motion.

http://www.kingston.gov.uk/browse/leisure/museum/museum_exhibitions/muybridge/machinery_and_equipment/zoopraxiscope.htm

What is it???

Bullet time is the registerd trade mark of warner bros.(Matrix's distrubitor) and refers to the digitally enhanced stimulation of variable speed photography used in films, adverts and even video games. Basically it is a type of slow motion or time lapse technique. However it allows the you to film imperceptible and un-filmable events, such as bullets. It also allows the point of view of the viewer to move around a scene at normal speed while the objects in the scene are slowed down.

Bullet time was originally achieved photographially by surrounding the subject with cameras. these would then take a pictures simulataneously or sequentially depending on the desired effect. the frames would then be arranged and displayed in sequence to create a orbiting viewpoint.
For many years, it has been possible to use computer vision techniques to create and render scenes with novel viewpoints sufficient enough for bullet time type effects. More recently, this has been formalised into what is none as free viewpoint television (FTV) which is bassically the live action version of bullet time.
Bullet time within the Matrix was pre-designed using CGI, which was then used as a guide to set up cameras on a track using laser targeting behind a green screen creating a complex curve through space. The cameras were then triggered at very close intervals from different viewpoints to create extreme slow motion. the frames were also scanned by a interpolation software to create even more frames to slow it down further and increase fluidity. They could also drop frames to speed up the action.

Getting Started

I have no clue how to go about reseaching this project, so... i'm just going to type 'Bullet Time' into google and find out what exactly it is.

One of the links that came up was wikipedia, which gave me a description of what bullet-time is and where the term comes from. It also gave me a historical background and a list of where the concept has been applied in film.

http://http//en.wikipedia.org/wiki/Time_slice_photography

So i'm going to use this as a base to start my Research.