ASC‑CDL: Overview
The ASC‑CDL (Academy‑specified Color Decision List) refines the CDL format with rigorous parameter definitions, file schemas, and reference implementations to ensure consistent behavior across compliant systems. It details how slope, offset, power, and saturation adjustments are to be interpreted and applied.
Specification and Compliance
Published by the ASC’s Technical Working Group in 2009, the standard includes:
- XML Schema: Defines required elements, data types, and units.
- Precision Rules: Minimum floating‑point accuracy for slope/power values.
- Interpolation Guidelines: How to blend CDL entries between timecode points.
Vendors must implement the spec exactly to be ASC‑CDL compliant.
ASC‑CDL: Use Cases
- On‑Set Previews: DITs export ASC‑CDLs to preview looks on reference monitors.
- Editorial Exchange: Editors import director’s preliminary grades to maintain visual consistency.
- VFX Conform: VFX artists apply CDL grades before rendering CG elements to match plate footage.
ASC‑CDL: Limitations
While ASC‑CDL covers primary color adjustments, it does not handle LUT transforms, log‑to‑linear conversions, or advanced node‑based operations. For complex grades, pipelines layer additional LUTs or proprietary metadata atop ASC‑CDLs.
ASC‑CDL: See Also
- CDL
- Look Metadata