Making Space _ Senses of Cinema

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n Cubitt is Director of the Program in Media and Communications at the University of Melbourne. His

lications include Timeshift, Videography, Digital Aesthetics, Simulation and Social Theory , The Cinema Effect

EcoMedia. He is series editor for Leonardo Books at MIT Press.

Bitmap, Colour, Codec

The meaning of the term cinemahas changed.Today we experience film across large and small

screens, only relatively rarely projected outside

lecture halls and the theatrical circuits. We watch

in aircraft, on the bus, on handhelds, with

earphones, on TV and plasma screens, tape, DVD

and Blu-Ray and a dozen internet formats. The

35mm photographic film that gave the medium its

me is no longer universal in filming, passing out of post-production, and scheduled for demolition

distribution. As a community of scholars we are still trying to understand what it is that we are

king at now.

e experience of digital cinema starts with screens. The two major formats for digital projection ital light projection (DLP) and Liquid Crystal on Silicon (LCOS) are geometrically the same as the

minant formats for fixed fluorescent screens, liquid crystal displays (LCD) and plasma screens. Big

hitectural screens using light-emitting diodes (LEDs) share the same structure. It even dominates

formats of digital cameras, charge-coupled devices (CCD) and complementary metaloxide

miconductor (CMOS) chips. This geometry is the rectangular grid of pixels ordered arithmetically

m top left. Because it is designed to handle any output from a computer, such screen displays are

re deeply sealed into contemporary screen culture than, say, standard aspect ratios were in the

ema. However your image is produced, it has to be displayed on the raster grid, also known as the

map display.

ere is an interesting history to this, stretching back to half-tone printing and the development of

e photos, the former essential to mass dissemination, the latter to journalistic speed innsmission, of photography. The principle of synchronised scanning moved from experiments with

neer fax technologies around 1900 into the cathode ray tube (CRT). The old CRTs were pretty

rry, so Sony introduced the Trinitron which placed a shadow mask, a grid of fine lines between

more or less random spray of phosphorescent molecules lining the inside of the tube, to give the

pression both of richer blacks, and of crisper definition. The shadow mask principle was adopted

computer displays, where each spot on the screen was given a numerical address so many pixels

he right or below the origin at top left. Those addresses now are hardwired into the computers

erating system. Redesigning the screen would mean redesigning pretty much everything from the

erating system up.

e other numerical factor in digital displays is the colour depth, defined by the number of bits

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ocated per pixel. Obviously the more data you attach to each pixel, the larger the number of colours

t can be shown. The problem is the second factor in colour display, the gamut, which is the range

colours that can be shown. In pretty much any of the devices I just listed, cameras included, and in

vast majority of printers, the gamut is only around 40% of the visible spectrum. Some colours are

t hard to get with the standard colours of phosphors red, green and blue. The RGB gamut isnt

y good at bright yellow, which in the human retina overlaps the red (actually in our eyes more

nge) and green cones, and so appears the brightest of colours (Sharp introduced a new four colour

system ACQUOS Quattron, including yellow pixels in 2010. Unavailable as yet in Australia, the

hor has been unable to assess their optical qualities: http://ces.cnet.com/8301-31045_1-

426897-269.html). RGB phosphors dont quite match the breadth of wavebands of the respectivenes in the human eye, and across much of the spectrum they cant achieve the same brightness.

s happens especially with blues: we are highly sensitive to blue, which overlaps with our scotopic

lourless) night vision: we can see way into the blue end of the spectrum. But getting that dim

ion to shine brightly on screens would take too much power (and generate too much heat). So

tware engineers bring in a third tool in colour management: colour difference. Various input

vices, like cameras, record the fact that light of the visible wavelengths is arriving. They pass that

a on to the software. The software then squeezes the incoming light into the available gamut. But

her than simply move the extreme blues and yellows etcetera into the nearest available spot, they

culate the difference between colours say between a mauve and a magenta and try to keep the

ative difference between them. The whole convolution moves all the colours, not just the extreme

es, so the result looks as if it has as much colour contrast, even though there is a lesser total range

n in ordinary visible light.

the screen is a grid, and the colour is manipulated. The third major factor in digital display is the

mpression-decompression algorithms or codecs. To get from visible light to a computer screen, the

velengths of light are converted into numbers matching the colours, and addresses matching

ere they are to appear. That is a considerable number of numbers for each pixel. For a good

mestic 12801024 high definition display, that would be 1,310,720 pixels and the address of the

tom right quadrant pixels have to have a minimum of eight digits in their addresses (obviously

re in binary!). Change these values once every 25th of a second over the two-hour runtime of a

ture film and you see the problem: vast quantities of data (and we havent mentioned sound yet).

imilar problem arises even in shooting with digital cameras. An individual frame is exposed: the

ht causes the release of electrons. That creates charge. The charge is guided through the use ofitively and negatively charged gutters in the chip through a timer gate into storage. So far it is just

arge the equivalent of the latent image in traditional photography. It has to be converted into

mbers in order to be taken over into digital storage. Typically this is handled by processing the

lected data in batches called blocks or groups of blocks: four neighbouring pixels, or sixteen,

cked to see whether they are pretty much the same colour. If so, the same colour number is

plied to the lot, making it much quicker to get them out of the vulnerable charge state and into the

ital state, so making room for the next frame one 25th of a second later.

tting data from the cameras storage into a computer, and then into editing software may require

er compression phases. Previewing on a monitor requires further compression. Then theres the

estion of delivering it to audiences. Terrestrial broadcasting used pretty strenuous compression to

the data through crowded airwaves. Internet and mobile media likewise: even with broadband,e and the cost per byte of data transfer have to be balanced against the resolution, colour depth

d accuracy that viewers will accept. Even DVD has to fit everything onto a finite space, and get it

m the disc to the screen as rapidly as possibly, This is the work of codecs. To cut a long story short,

codecs crush the image. YouTube crushes hard. A Blu-Ray movie or an FC Pro file crush

nsiderably less. But everything from the moment of digitisation on is crushed. I need only make

e last point: the means for doing this includes a process called vector prediction.

s is infuriating, only partly because vectors have a very different role elsewhere in digital imaging.

mators will recognise the principles: the codec seeks out keyframes where there is substantial

ange across the whole field of the image. Then it automates in-betweening to get from the first

yframe in a sequence to the last, sampling as it goes along to update and check for basic accuracy.
http://ces.cnet.com/8301-31045_1-10426897-269.htmlhttp://ces.cnet.com/8301-31045_1-10426897-269.htmlhttp://ces.cnet.com/8301-31045_1-10426897-269.htmlhttp://ces.cnet.com/8301-31045_1-10426897-269.html


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e idea is that if youre watching the cricket, you arent watching the grass, which can be relied on to

y the same colour. Big saving in information. Vector prediction then tells the software which areas

he image seem to change most and which least from frame to frame. Those that dont change

me out as blocky patches because the unit is those Groups of Blocks, fetchingly referred to as GoBs.

what does all this mean? Ill concentrate on one device where three features come together, the

D chip standard in most digital video and still cameras. Light comes in as a rain of photons over

duration that the shutter is open: lets say slightly less than a 25th of a second for a video frame.

e photons have different wavelengths, and even though they arrive over a very short period by

man standards, recall that they are travelling at the speed of light. There are lots of them. When

y arrive, they react with the CCD to produce a charge. This charge is an average of the wavelengths

all the different photons, and the average is applied across the width of the pixel square. This

raging involves effectively sampling from the whole spectrum falling in the square and arriving at

ngle figure to represent it. When the charge is deposited in digital form for storage, the average is

nded up or down to a whole number there are no digital fractions. The frequency of the

raged wave form, what we see is a colour, is then managed, convoluted to match the available

our gamut. The question here is not proximity to human vision but the translation of flux into

raged unit steps. The process is geared towards a good-enough rendering of the scene, as

asured against the visual perception of a standard observer.

e standard observer also has an interesting history. In 1931, arguments between physicists and

chologists over how to standardise colour descriptions reached a pitch. Both agreed that the

mmission International de lEclairage, one of the older international standards bodies, had as a

mit the task of providing metrics for the notoriously unstable and tricky field of pigments, dyes and

ht-sources. How could you guarantee that the colour of your flag was the same from year to year,

en the vagaries of bleaching, fading, rapidly changing industrial colour manufacture, different

nting technologies and their inks, different conditions of illumination? Unable to find a common

guage, the dispute over whether colour was a matter of the physics of frequency or the subjective

pression of observers under different light conditions, talks were deadlocked until a group of US

chologists, inspired by the social physics of Alphonse Quetelet, inventor of statistical techniques

sociology, (1)tested a group of students. Testing their responses to colour cards under different

hting conditions, they constructed, as Quetelet had constructed the average man a standard

erver. (2)It is, I believe, a triumphant moment in the establishment of what Michel Foucault calls

politics (3): the replacement of rule through panoptic discipline by the management ofpulations through probability and statistical goal-setting.

the same time, the whole-number enumeration of things parallels another critical factor in the

itical economy of our times: the commodity form. The harsh reality is that once a colour value has

cribed in the whole-number language of hexadecimal or the other coding systems (HSV, LAB,

B) available in digital devices, it is exchangeable. No only can the number be handled

thmetically as we do with Photoshop filters. It can be picked up and moved. Colour values are no

ger semantic grounded in use but arithmetic based in exchange. Between the processes of

tistical averaging and arithmetical description, biopolitics and information commodity, light is

nufactured for digital cinema in technologies which are symptomatic of a very precise condition of

ntemporary social organisation: the database economy.

now we have the basic building blocks of digital cinema: bitmaps, colour management and codecs.

e first traces its history back to printing, losing in the process much of the textural richness of older

hniques. The second can be traced back through the industrialisation and standardisation of

our. The third, codecs, has an interesting relationship with the geometry of perspective, which is

ere, at last, I want to begin.

yers, Grading and Sprites

e Teatro Olimpico in Vicenza designed by Palladio and completed by Scamozzi is a triumph of

roque stage design, with its forced perspective only clearly visible from the central area of the

ditorium (the confusing side-on view being blanked out by a false wall of neo-classical ornament).


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ertis technique of the veil and its tracery of fine lines suggests a shared history with another

ual technology which has had an even more important structuring role in digital visual culture: the

p. Alberti inherited the general idea from scale drawing, the practice of designing mural-sized

rks on gridded panels for transfer to the walls. This scalability is intrinsic to the geometric

nciple of projection, which renders something on a larger or smaller surface. The mercator

jection is just one of the many that have guided and shaped cartography and now geographic

ormation systems. Architects likewise have employed axonometric and other projections. Although

y have a very different genealogy, both databases and spreadsheets, as spatial representations of

mporal relationship, also use a kind of projection, and in turn are used to produce projections of

ure states of affairs. And of course this is the optical principle of projecting, in the case of DLP formple, from tiny square mirrors onto large screens.

e second Alberti quote about protruding objects goes against the idea of the picture as a window,

deeply associated with his name, suggesting instead a reversal: that it is not we who look into the

ture, but the picture that penetrates our world. The importance of black and white in this is

icated by Samuel Edgerton (17)with an illustration from Christoph Jamnitzers (18)book of

gravings, a medium deeply associated with restriction of the palette to black and white. This

trusion based on extremes of light and shade is central to trompe loeuil painting, from

ravaggio to Hoogstraaten, who also designed a projecting shadow theatre as well as the delightful

mpe-loeuil perspective box in the National Gallery, London. The Jamnitzer engravings are

viously geometrical in construction. This is the first significant aspect of the construction of 3D

ce that does not involve a specifically arithmetic relationship.

lear expression of what is at stake can be derived from inspecting an important technique in

ating volume in digital media: shading. Of the many types of shading used in digital imaging,

uraud and Phong are the most widespread. The former was invented in 1971. Gouraud shading

s samples of illumination effects on curved surfaces, extrapolating from them the likely effects of

hting on objects constructed from polygons, geometric primitives used in wireframe CGI. Curves in

ygon construction are composed of smaller, usually regular, flat geometric shapes selected by

raging the tangents to the local curvature of the object as a single plane. For each of these flat

faces, there is a surface normal, that is, a line perpendicular to the flat plane. Once a virtual light

urce has been constructed, it will strike one polygon at the perpendicular, and neighbouring

ygons at gradually more oblique angles. Gouraud shading takes the average of surface normals for

oured polygons meeting at a specific point or vertex, and interpolates a colour value based on therage. The beauty of Gouraud shading is its efficiency. Interpolating an average is swift, and uses

s computing power than trying to trace every point on a surface. The drawback however is that if a

hlight occurs elsewhere than at a vertex, it may not be included in the average, and either lost, or

minated abruptly, giving a tessellated effect. One solution is to design objects with simple

metric surfaces, as is the case in many computer games, and to restrict the number of light

urces involved. The results are generally felt to be acceptable where interaction and therefore speed

computing is the major attraction, but for more sophisticated shading, the Phong system is

ferred.

ong shading began in the observation that rough surfaces reflected less light than smooth: the more

rror-like a surface, the more light it would return. Bui Tuong Phong established a complex

orithm for calculating relations between the ambient tone of the object, diffuse reflections typicalough surfaces and highlights typical of shiny ones, and various aspects of reflection. This

orithm is shared with Gouraud shading, but in Phong shading, reflectance is calculated at each

el, not just the vertices of adjoining polygons. The result is much smoother rendering, albeit at the

pense of much heavier use of computing power. The trick is to presume that the curvature of the

face varies smoothly and constantly. Phong shading provides the characteristic billiard ball style of

mputer graphics, although it allows for a wide range of effects, especially when combined with

er 3D graphics tools. Yet like Gouraud shading, it averages around a unit: the unit of the pixel, far

aller than a polygon, but still a finite and enumerable quantity. The oddity about this is that the

oothly changing gradients which it presumes is based not on pixels but on vectors, which are not

rinsically unit-based.


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ewarned and forearmed managerialist commodification that the grid expresses as the iron fist of

market, and the perpetual status quo of risk management in a polity where elections seem to be

n exclusively on the basis of fear of change. The vector, and the contradiction between vector and

thmetic forms, including the very screens that contain them, point, with all due trepidation,

wards a distant shore where things are no longer as they are.

s article has been peer reviewed

thors note: This research was made possible by an Australian Research Council Discovery Grant.

we special thanks to my colleagues Daniel Palmer and Les Walkling for their input.

DNOTES

Ian Hacking, The Taming of Chance, Cambridge: Cambridge University Press, 1990.

Sean F. Johnston,A History of Light and Colour Measurement: Science in the Shadows, Institute of Physics,

Bristol and Philadelphia, 2001.

Michel Foucault, The Birth of Biopolitics: Lectures at the Collge de France 1978-1979 , ed. Michel Senellart,

trans. Graham Burchell, Basingstoke: Palgrave Macmillan, 2004.

Adolphe Appia,Adolphe Appia: Essays, Scenarios, and Designs, ed. Richard C. Beacham, trans. Walther R.

Volbach, Ann Arbor: UMI Research Press, 1989.

Henri Lefebvre, The Production of Space, trans. Donald Nicholson-Smith, Oxford: Blackwell, 1991, p. 188.

Andr Bazin, An Aesthetic of Reality, in What is Cinema?, Volume 2, trans. Hugh Gray, Berkeley: University of

California Press, 1971, p. 26-7.

Tim Mara, The Thames and Hudson Manual of Screen Printing, London: Thames & Hudson, 1979.

Joe Fordham, The Lord of the Rings: The Return of the King: Journeys End in Cinefex, n.96, January, 2004,

p. 115-6.

Marta Braun,Picturing Time: The Work of Etienne -Jules Marey (1830-1904), Chicago: University of Chicago

Press, 1992; Franois Dagognet,Etienne-Jules Marey: A Passion for the Trace, trans. Robert Galeta with

Jeanine Herman, New York: Zone Books, 1992; Rebecca Solnitt,River of Shadows: Eadweard Muybridge and

the Technological Wild West, New York: Viking, 2003.

Norman M. Klein, The Vatican to Vegas: A History of Special Effects , New York: The New Press, 2004.

Erwin Panofsky,Perspective as Symbolic Form, trans. Christopher S Wood, New York: Zone Books, 1991 [1924-

5].

Hubert Damisch, The Origin of Perspective, trans, John Goodman, Cambridge MA: MIT Press, 1994; originally

published as,LOrigine de la perspective, Paris: Flammarion, 1987.

Leon Alberti, Leon,Il nuovo De Piictura di Leon Alberti The New De Pictura of Leon Alberti, ed. and trans.Rocco Sinisgalli, Roma: Universit di Roma La Sapienza, 2006.

Albrecht Drer, The Painters Manual, trans. Walter L Strauss, New York: Abaris Books, 1977.

Alberti, p. 227

Anne Friedberg, The Virtual Window:From Alberti to Microsoft, Cambridge MA: MIT Press, 2006.

Samuel Y. Edgerton, The Mirror, The Window and the Telescope: How Renaissance Linear Perspective

Changed Our Vision of the Universe , Ithaca: Cornell University Press, 2009, p. 136.

Christoph Jamnitzer,Neuw Grottessken Buch, einleitung, Heinrich Gerhard Franz, Akademische Druck-u.

Verlagsanstalt, Graz. 1966.

Jay David Bolter and Richard Grusin,Remediation: Understanding New Media, Cambridge MA: MIT Press,

1999.

Nicholas A. Vardac,Stage to Screen: Theatrical Origins of Early Film: David Garrick to D.W. Griffith , New

York: DaCapo, 1949; Ben Brewster and Lea Jacobs, Theatre to Cinema: Stage Pictorialism and the EarlyFeature Film, Oxford: Oxford University Press, 1997.

Jean-Louis Comolli and Pierre Narboni, Cinema/ Ideology/ Criticism (1) & (2), trans. Susan Bennett, in John

Ellis (ed.),Screen Reader 1: Cinema/Ideology/Politics, SEFT, London, 1977, pp. 2-11 and 36-46.

Ludwig Wittgenstein, Tractatus Logico-Philosophicus, trans. D.F. Pears and B.F. McGuinness, London:

Routledge & Kegan Paul, 1961.

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