CDL

Overview

A Color Decision List (CDL) is a lightweight, standardized file format that encodes primary color corrections—lift, gamma, gain, and saturation—in a compact, interoperable way. Developed by the ASC (Academy of Motion Picture Arts and Sciences), CDLs allow different grading and editing systems to exchange and apply basic color adjustments consistently.

History and Adoption

Introduced in 2006 by the ASC’s Color Encoding Working Group, the CDL specification addressed the need for a common interchange format. Early adopters included FilmLight Baselight, Autodesk Lustre, and DaVinci Resolve. The format’s simplicity ensured rapid uptake across hardware and software vendors.

Technical Details

A CDL file is an XML or plain text sidecar containing timecode‑indexed entries, each specifying:

Parameter	Description
Lift	Shadows adjustment (RGB offset)
Gamma	Midtones adjustment (power function)
Gain	Highlights adjustment (RGB multiplier)
Saturation	Color intensity modifier

Example snippet:

<ColorDecision>
  <SOPNode>
    <Slope>1.1 1.05 1.0</Slope>
    <Offset>0.01 -0.02 0.0</Offset>
    <Power>1.0 1.0 1.0</Power>
  </SOPNode>
  <SatNode>
    <Saturation>1.2</Saturation>
  </SatNode>
</ColorDecision>

Workflow Integration

Colorists import CDLs into grading suites as starting points, layering them under advanced secondary corrections. Directors and cinematographers can review proxy grades embedded via CDL before final color finish.

See Also

• ASC‑CDL
• Look Metadata