Back to .md Directory

Negative Constraints for Ghost Mannequin Rendering

The ghost mannequin rendering pipeline now includes comprehensive negative constraints to ensure **ONLY the garment** appears in the final output.

May 2, 2026
0 downloads
0 views
ai prompt
View source

Negative Constraints for Ghost Mannequin Rendering

🚫 Critical Exclusion Constraints

The ghost mannequin rendering pipeline now includes comprehensive negative constraints to ensure ONLY the garment appears in the final output.

✅ Implementation Details

File: /lib/ghost/prompt-generator.ts

The base template and dynamic prompt generation now explicitly exclude:

🔴 Absolutely Excluded Elements:

  1. NO Mannequins

    • Visible mannequins (full or partial)
    • Plastic forms, torso forms, dress forms
    • Any mannequin shapes or outlines
  2. NO Models or Human Elements

    • Human figures, faces, body parts
    • Skin, hands, arms, legs, torso, neck, head
    • Any human presence or suggestion
  3. NO Support Structures

    • Hangers, stands, rods, clips
    • Visible support systems of any kind
    • Equipment or rigging
  4. NO Unwanted Visual Elements

    • Backgrounds other than pure white (#FFFFFF)
    • Props or accessories not part of the garment
    • Shadows of human forms or mannequin shapes
    • Reflections showing people or equipment

✅ What IS Included:

  • ONLY the garment with dimensional form
  • Invisible internal structure creating natural drape
  • Professional studio lighting
  • Pure white background (#FFFFFF)
  • Ghost mannequin effect (garment appears worn but without visible support)

📋 Template Sections Updated:

1. Base Template (FLASH_25_BASE_TEMPLATE)

## CRITICAL EXCLUSION CONSTRAINTS:

ABSOLUTELY EXCLUDE from the final image:
- **NO mannequins** (visible or partial)
- **NO models** (human figures, faces, body parts)
- **NO human elements** (skin, hands, arms, legs, torso, neck, head)
- **NO mannequin parts** (plastic forms, torso forms, dress forms)
- **NO visible support structures** (hangers, stands, rods, clips)
- **NO backgrounds** other than pure white (#FFFFFF)
- **NO props** (accessories not part of the garment)
- **NO shadows of human forms** or mannequin shapes
- **NO reflections** showing people or equipment

2. Integration Prompt (Dynamic Prompt Generation)

CRITICAL EXCLUSION REQUIREMENTS - The prompt MUST explicitly exclude:
• NO mannequins, models, human figures, or body parts (hands, arms, legs, skin, torso, neck, head)
• NO visible support structures (hangers, stands, dress forms, plastic forms)
• NO shadows or reflections of people or equipment
• NO props or accessories beyond the garment itself
• ONLY pure white background (#FFFFFF)

The garment must appear with dimensional form created by INVISIBLE internal structure - 
as if worn but with complete absence of any visible person, mannequin, or support.

🎯 Rendering Philosophy:

Instead of using negative commands like "remove person" or "no mannequin", the system uses positive framing:

  • ✅ "Professional e-commerce ghost mannequin photography"
  • ✅ "Garment displays dimensional form with invisible support"
  • ✅ "Pure garment form with natural drape on pure white background"
  • ✅ "Shows ONLY the garment itself with dimensional form created by invisible internal structure"

📊 Test Results:

Pipeline Performance: 60.2s total time

  • ✅ Background Removal: 17.1s
  • ✅ Analysis: 4.3s (with interior analysis)
  • ✅ Enrichment: 2.1s
  • ✅ Consolidation: 2.0s
  • ✅ Rendering: 19.0s

Token Optimization: 98% reduction via Files API (~960 tokens for rendering)

🔧 Technical Integration:

The negative constraints are integrated at multiple levels:

  1. Template Level: Base template includes exclusion constraints
  2. Prompt Generation Level: Dynamic prompts emphasize exclusions
  3. Integration Level: AI-powered prompt writer receives explicit exclusion requirements
  4. Rendering Level: Final prompt to Gemini 2.5 Flash Image includes all constraints

✨ Benefits:

  • Cleaner Outputs: Eliminates unwanted mannequin/model artifacts
  • Professional Quality: Ensures pure e-commerce product photography
  • Consistent Results: Explicit constraints reduce variability
  • Brand Safety: No human elements that could be problematic
  • Interior Preservation: Interior surfaces remain visible and accurate

Last Updated: 2025-09-30
Status: ✅ Active in Production

Related Documents