introduction to color management for film and tv igor riđanović

Introduction to Color Managementfor Film and TVIgor Riđanović

Why color manage in food industry?

Why color manage in retail?

commonsource

multipledisplaydevices

Why color manage in media?

correct color interpretation incorrect color interpretation

Why color manage in post?

Why color manage in post?

What is color management?

Perceptually consistent color across a range of devices

Consistent color within a pipeline Interoperability

Why is color management important in film and TV?

Brand identity

Protects integrity of creative intent Maintains suspension of disbelief

right wrong

The nature of light and color

The nature of light and color

Objects and living beings have no color

Light energy absorption, reflection and transmission

3D model Copyright © 2003-2013 Andrew Kator & Jennifer Legaz

Rods see low light and no color

Three type of cones can see color Near logarithmic response to luminance

Hans-Werner Hunziker

How do we see light and color?

S, M and L cones

How do we see light and color?

linear light intensity

How do we see light and color?perceivedbrightness

perceivedbrightness

doubling light intensity

Wolphram|Alpha

Additive and subtractive color mixing

Pko Cantus

Color model—an abstract primary color mixing principle

Color space—specific values for the primaries Color gamut—unambiguous color set defined by the primaries

Color model and color space

CIE XYZ(1931) color space

CIE xychromaticity diagram

PAR

sRGB color space

Device independent (example: CIE XYZ)

Device dependent (example: Rec. 709)

Color space classification

Examples:

Traditional CMYK press Analog and Digital TV

Device dependent color

In RGB color model each pixel is represented bythe additive mix of its three channels (R + B + G)

R 205G 012B 005

R 000G 000B 000

R 255G 255B 255

Device dependent color—numerical representation

Bit depth determines color precision

1 bit: fax 8 bit: grayscale 8 bit per channel: truecolor

Device dependent color—numerical representation

Device dependent color—numerical representation

A bit is a binary numeral representing either “0” or “1”

1 bit: 2 levels

2 bit: 4 levels

10 bit: 1024 levels

Values are intrinsically tied to the device

R 255G 255B 000

sRGB color space(computer monitor)

R 255G 255B 000

mystery color space(some handheld device)

Device dependent color—numerical representation

R 205G 012B 005

R 205G 012B 005

R 205G 012B 005

device 1

device 2

source device

Device dependent color

R ?G ?B ?

R 205G 012B 005

device 2

source device

Device dependent color

R 212G 008B 010

R 205G 012B 005

device 2

source device

Device dependent color

CMS

Device dependent color

Color management:

Typically translates color values from one device dependent color space to another device dependent color space with respect to gamut, gamma and dynamic range

Device dependent color—gamut

Rec. 2020 vs.Rec. 709 color gamut

GrandDrake

Rec. 709 vs.DCI-P33D color gamut

Device dependent color—gamut

Device dependent color—gamma

linear gamma 2.2 gammaWolfram|Alpha

Device dependent color—dynamic range

higher dynamic range

lower dynamic range

reduced dynamic rangegamma mismatch

original gamut mismatch

Case Study: Black and White TV (simplified)

subjectcamera

TV set

OTA broadcast

video

Traditional TV color management

Single input, single output

TV camera editorial TV monitor

TV camera

γ = 0.45

γ = 2.5

Contemporary color management requirements

5D editorial HD monitor

film scan

Alexa

graphics

Vimeo

DVD

QT MOV

. . . VFX

delivery. . .

Color management system

Color management system

Rendering intent defines how values are translated

from one color gamut to another: Perceptual Saturation Relative colorimetric Absolute colorimetric

Color management system

Calibration and profiling:

Calibration brings device to factory recommended specification Profiling builds a fingerprint of the specific device's differential from a

standard color space specification

Good news!

Color management in most NLEs is much simpler.

Color management can be more sophisticated in picture finishing and

color correction systems.

Sometimes aided by the operating system

Can be dependent on user selected LUTs or matrices

Transforming the numbers

1D LUT

3D LUT 3X3 matrix

R G B0.034439 0.034439 0.034439 0.034712 0.034712 0.034712 0.034988 0.034988 0.034988 0.035266 0.035266 0.035266 0.035546 0.035546 0.035546 0.035828 0.035828 0.035828. . .

If input R or G or B = 0Output R or G or B = 0.034439

012345

output valuesinput values

Transforming the numbers

1D LUT

3D LUT 3X3 matrix

Rec. 709 vs.DCI-P33D color gamut

Transforming the numbers

1D LUT

3D LUT 3X3 matrix

Mathematical transformation.

Not as precise as 3D LUT but adequate

for many applications.

How do popular programs color manage?

Media Composer

Creative Cloud FCP X

How do popular programs color manage?

601/709 MC 6.x TV monitor

sRGB

tape 709

files

files

user choices

Rec. 709 Rec. 709

How do popular programs color manage?

0 255

0 25523516

0 mV

16

700 mV

superblack superwhite

How do popular programs color manage?

without dithering with dithering

Recent developments

CDL

Scene referred linear ACES

Special Thanks

James Mathers, Digital Cinema Society

Matt Feury, Avid Technologies

Further reading

Fraser, Murphy and Bunting (2005). Real World Color Management.Berkeley: Peachpit Press.Graham, S. (2002). The Science of Imaging: An Introduction. Bristol: IOP Publishing.Bloch, C. (2007). The HDRI Handbook. Santa Barbara: Rocky Nook.Kennel, G. (2007). Color and Mastering for Digital Cinema. Burlington: Focal Press.

www.poynton.comwww.lightillusion.com

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