Skill: Color Pipeline (cinef.skill.color_pipeline)

Purpose

Enforce the show's color pipeline rules across all shots. This is a SHOW-LEVEL skill — it applies universally. Every override layer that modifies color or lighting must comply with these rules.

This skill is not executed directly — it acts as a constraint layer that other skills (relight, segment) must check before committing.

When to Use

• Before committing any relight override (validate color space compliance)
• When a user asks about color management or LUT application
• When reviewing a shot for color pipeline violations
• Before dailies or final delivery

Show Color Rules

1. Working color space: ACEScg (ACES 2065-1 acceptable for interchange)
2. Never output: sRGB, Rec709, or Display P3 in override layers
3. Color metadata: Every override layer with color properties must include custom string colorSpace = "ACEScg" on the affected prim
4. Gamut preservation: No clipping — if AI-generated values exceed ACEScg gamut, flag in QC report rather than clamping
5. LUT application: LUTs are for viewing only — never bake a LUT into an override layer

Validation Checks

When validating a layer for color pipeline compliance:

• All color3f values are in ACEScg range (no negative components unless physically motivated)
• No sRGB/Rec709 transfer function applied in the layer
• colorSpace metadata present on prims with color properties
• Lighting intensity values are physically plausible (0.0 – 10.0 range for most lights, flag anything > 10.0 for review)
• HDR environment maps referenced with correct color space annotation

Output

This skill does not produce override layers. It produces a compliance report in the shot's qc/ directory:

{
    "skill_id": "cinef.skill.color_pipeline",
    "shot_id": "shot_010",
    "timestamp": "<ISO 8601>",
    "passed": true,
    "checks": [
        {"rule": "color_space", "value": "ACEScg", "passed": true},
        {"rule": "gamut_clipping", "value": false, "passed": true},
        {"rule": "intensity_range", "max_found": 3.0, "limit": 10.0, "passed": true}
    ]
}

Constraints

• This is a SHOW-LEVEL skill — it never changes per scene or shot
• It constrains OTHER skills, not the scene data itself
• Never modify base.usda to add color space — only validate override layers
• If a shot has a valid artistic reason to deviate (e.g., stylized sequence), the user must explicitly approve the exception