Visual effects: Difference between revisions

{{Short description|Various processes by which imagery is created}}

{{More citations needed|date=February 2018}}

'''Visual effects''' (sometimes abbreviated '''VFX''') is the process by which imagery is created or manipulated outside the context of

[[File: Madame Nobel - film set at the Embassy of France in Vienna May 2014 08.jpg|thumb|right|A [[period drama]] set in [[Vienna]] uses a [[Chroma key|green screen]] as a backdrop, to allow a background to be added during [[post-production]].]]

* [[Special effect]]s: Special effects (often abbreviated as SFX,<!--usually ref to sound fx only--> SPFX, F/X or simply FX) are illusions or visual tricks used in the [[theatre]], [[film]], [[television]], [[video game]] and [[simulator]] industries to simulate the fictional events in a [[Narrative|story]] or [[virtual world]]. With the emergence of digital film-making, a distinction between special effects and visual effects has grown, with the latter referring to digital [[post-production]] while "special effects" refers to mechanical and optical effects. Mechanical effects (also called [[Practical effect|practical]] or [[physical effects]]) are usually accomplished during the live-action shooting. This includes the use of mechanized [[Theatrical property|props]], scenery, [[scale model]]s, [[animatronics]], [[pyrotechnics]] and atmospheric effects: creating physical wind, rain, fog, snow, clouds, making a car appear to drive by itself and blowing up a building, etc. Mechanical effects are also often incorporated into set design and makeup. For example, [[prosthetic makeup]] can be used to make an actor look like a non-human creature. Optical effects (also called photographic effects) are techniques in which images or film frames are created photographically, either "in-camera" using [[multiple exposures]], [[Matte (filmmaking)|mattes]], or the [[Schüfftan process]] or in post-production using an [[optical printer]]. An optical effect might place actors or sets against a different background.

 

*[[Motion capture]]: Motion-capture (sometimes referred as mo-cap or mocap, for short) is the process of recording the [[motion (physics)|movement]] of objects or people. It is used in [[Military science|military]], [[entertainment]], [[sports]], medical applications, and for validation of computer vision<ref>{{cite web|author=David Noonan, Peter Mountney, Daniel Elson, Ara Darzi, Guang-Zhong Yang|title=A Stereoscopic Fibroscope for Camera Motion and 3D Depth Recovery During Minimally Invasive Surgery|work=In proc ICRA 2009|pages=4463–4468|url=http://www.sciweavers.org/external.php?u=http%3A%2F%2Fwww.doc.ic.ac.uk%2F%7Epmountne%2Fpublications%2FICRA%25202009.pdf&p=ieee}}</ref> and robotics.<ref>Yamane, Katsu, and Jessica Hodgins. "[https://pdfs.semanticscholar.org/8de6/2ececd067c3d9e7d6f3462164a9a821d9e0a.pdf Simultaneous tracking and balancing of humanoid robots for imitating human motion capture data]." Intelligent Robots and Systems, 2009. IROS 2009. IEEE/RSJ International Conference on. IEEE, 2009.</ref> In [[filmmaking]] and [[video game development]], it refers to recording actions of [[Motion capture acting|human actors]], and using that information to animate [[digital character]] models in 2-D or 3-D [[computer animation]].<ref>NY Castings, Joe Gatt, [http://www.nycastings.com/dmxreadyv2/blogmanager/v3_blogmanager.asp?post=motioncaptureactors Motion Capture Actors: Body Movement Tells the Story] {{webarchive|url=https://web.archive.org/web/20140703113656/http://www.nycastings.com/dmxreadyv2/blogmanager/v3_blogmanager.asp?post=motioncaptureactors |date=2014-07-03 }}, Accessed June 21, 2014</ref><ref name=twsBackstage>Andrew Harris Salomon, Feb. 22, 2013, Backstage Magazine, [http://www.backstage.com/news/spotlight/growth-performance-capture-helping-gaming-actors-weather-slump/ Growth In Performance Capture Helping Gaming Actors Weather Slump], Accessed June 21, 2014, "..But developments in motion-capture technology, as well as new gaming consoles expected from Sony and Microsoft within the year, indicate that this niche continues to be a growth area for actors. And for those who have thought about breaking in, the message is clear: Get busy...."</ref><ref name=twsGuardian>Ben Child, 12 August 2011, The Guardian, [https://www.theguardian.com/film/2011/aug/12/andy-serkis-motion-capture-acting Andy Serkis: why won't Oscars go ape over motion-capture acting? Star of Rise of the Planet of the Apes says performance capture is misunderstood and its actors deserve more respect], Accessed June 21, 2014</ref> When it includes face and fingers or captures subtle expressions, it is often referred to as performance capture.<ref name=twsWired>Hugh Hart, January 24, 2012, Wired magazine, [https://www.wired.com/2012/01/andy-serkis-oscars/ When will a motion capture actor win an Oscar?], Accessed June 21, 2014, "...the Academy of Motion Picture Arts and Sciences' historic reluctance to honor motion-capture performances .. Serkis, garbed in a sensor-embedded Lycra body suit, quickly mastered the then-novel art and science of performance-capture acting. ..."</ref> In many fields, motion capture is sometimes called motion tracking, but in filmmaking and games, motion tracking usually refers more to '''[[match moving]]'''.

*[[Matte painting]]: A matte painting is a painted representation of a landscape, set, or distant location that allows filmmakers to create the illusion of an environment that is not present at the filming location. Historically, matte painters and film technicians have used various techniques to combine a matte-painted image with live-action footage. At its best, depending on the skill levels of the artists and technicians, the effect is "seamless" and creates environments that would otherwise be impossible or expensive to film. In the scenes the painting part is static and movements are integrated on it.

*[[Animation]]: '''Animation''' is a method in which [[Image|figures]] are manipulated to appear as moving images. In [[traditional animation]], images are drawn or painted by hand on transparent [[cel|celluloid sheets]] to be photographed and exhibited on [[film]]. Today, most animations are made with [[computer-generated imagery]] (CGI). [[Computer animation]] can be very detailed [[3D computer graphics|3D animation]], while [[2D computer graphics|2D computer animation]] can be used for stylistic reasons, low bandwidth or faster [[real-time rendering]]s. Other common animation methods apply a [[stop-motion]] technique to two and three-dimensional objects like [[cutout animation|paper cutouts]], [[puppet]]s or [[Clay animation|clay figures]]. Swift progression of consecutive images with minor differences is a common approach to achieving the stylistic look of animation. The illusion—as in motion pictures in general—is thought to rely on the [[phi phenomenon]] and [[beta movement]], but the exact causes are still uncertain. [[Analog device|Analog]] mechanical animation media that rely on the rapid display of sequential images include the [[phenakistiscope|phénakisticope]], [[zoetrope]], [[flip book]], [[praxinoscope]] and film. [[Television]] and [[video]] are popular electronic animation media that originally were analog and now operate [[digital media|digitally]]. For display on the computer, techniques like [[animated GIF]] and [[Flash animation]] were developed.

*[[3D modeling]]: In [[3D computer graphics]], 3-D modeling is the process of developing a mathematical representation of any ''[[surface (mathematics)|surface]]'' of an object (either inanimate or living) in [[Three-dimensional space|three dimensions]] via [[3D computer graphics software|specialized software]]. The product is called a 3-D model. Someone who works with 3-D models may be referred to as a 3-D artist. It can be displayed as a two-dimensional image through a process called ''[[3D rendering]]'' or used in a [[computer simulation]] of physical phenomena. The model can also be physically created using [[3D printing]] devices.

*[[Skeletal rigging|Rigging]]: Skeletal animation or rigging is a technique in [[computer animation]] in which a [[Character (animation)|character]] (or another articulated object) is represented in two parts: a surface representation used to draw the character (called the ''[[Polygon mesh|mesh]]'' or ''skin'') and a hierarchical set of interconnected parts (called ''bones'', and collectively forming the ''skeleton'' or ''rig''), a virtual [[Armature (sculpture)|armature]] used to animate (''pose'' and ''key-frame'') the mesh.<ref>{{cite web |title=Skeletal Animation |last=Soriano | first=Marc |publisher=Bourns College of Engineering |url= http://alumni.cs.ucr.edu/~sorianom/cs134_09win/lab5.htm |access-date=5 January 2011}}</ref> While this technique is often used to animate humans and other organic figures, it only serves to make the animation process more intuitive, and the same technique can be used to control the deformation of any object—such as a door, a spoon, a building, or a galaxy. When the animated object is more general than, for example, a humanoid character, the set of "bones" may not be hierarchical or interconnected but simply represent a higher-level description of the motion of the part of the mesh it is influencing.

*[[Rotoscoping]]: Rotoscoping is an [[animation]] technique that [[animators]] use to trace over motion picture footage, [[frame (film)|frame]] by frame, to produce realistic action. Originally, animators projected photographed live-action movie images onto a [[glass]] panel and traced over the image. This projection equipment is referred to as a ''rotoscope'', developed by Polish-American animator [[Max Fleischer]]. This device was eventually replaced by computers, but the process is still called rotoscoping. In the visual effects industry, ''rotoscoping'' is the technique of manually creating a [[Matte (filmmaking)|matte]] for an element on a live-action plate so it may be [[Digital compositing|composited]] over another background.<ref name="PM">{{cite web|url=https://www.popmatters.com/160872-american-pop-matters-ron-thompson-the-illustrated-man-unsung-2495833587.html|work=[[PopMatters]]|date=2012-08-02|title='American Pop'... Matters: Ron Thompson, the Illustrated Man Unsung|author=Maçek III, J.C.|url-status=live|archive-url=https://web.archive.org/web/20130824143210/http://www.popmatters.com/pm/column/160872-american-pop-matters-ron-thompson-the-illustrated-man-unsung/|archive-date=2013-08-24}}</ref><ref>"Through a 'Scanner' dazzlingly: Sci-fi brought to graphic life" USA TODAY, August 2, 2006 Wednesday, LIFE; Pg. 4D [https://www.usatoday.com/life/movies/news/2006-08-01-rotoscoping_x.htm WebLink] {{webarchive|url=https://web.archive.org/web/20111223004058/http://www.usatoday.com/life/movies/news/2006-08-01-rotoscoping_x.htm |date=2011-12-23 }}</ref> [[Chroma key]] is more often used for this, as it is faster and requires less work, however, rotoscope is still used on subjects that are not in front of a green (or blue) screen, due to practical or economic reasons.

*[[Match moving|Match Moving]]: In visual effects, match-moving is a technique that allows the insertion of computer graphics into [[live-action]] footage with correct position, scale, orientation, and motion relative to the photographed objects in the shot. The term is used loosely to describe several different methods of extracting camera [[Motion (physics)|motion]] information from a [[motion picture]]. Sometimes referred to as motion-tracking or camera-solving, match moving is related to [[rotoscoping]] and [[photogrammetry]]. Match moving is sometimes confused with [[motion capture]], which records the motion of objects, often human actors, rather than the camera. Typically, motion capture requires special cameras and sensors and a controlled environment (although recent developments such as the [[Kinect]] camera and [[Apple Inc.|Apple's]] [[Face ID]] have begun to change this). Match moving is also distinct from [[motion control photography]], which uses mechanical hardware to execute multiple identical camera moves. Match moving, by contrast, is typically a software-based technology applied after the fact to normal footage recorded in uncontrolled environments with an ordinary camera. Match moving is primarily used to track the movement of a camera through a shot so that an identical virtual camera move can be reproduced in a [[3D animation]] program. When new CGI elements are composited back into the original live-action shot, they will appear in a perfectly matched perspective.

*[[Compositing]]: Compositing is the combining of visual elements from separate sources into single images, often to create the illusion that all those elements are parts of the same scene. [[Live-action]] shoots for compositing is variously called "[[chroma key]]", "blue screen", "green screen" and other names. Today, most, though not all, compositing is achieved through [[digital image]] manipulation. Pre-[[digital compositing]] techniques, however, go back as far as the trick films of [[Georges Méliès]] in the late 19th century, and some are still in use.

 

[[Category:Visual effects| ]]

[[Category:Cinematic techniques]]

[[Category:Film and video technology]]