Implements detection of embedded images used for redaction/covering:
- Analyzes embedded images for mostly black (avg RGB <= 30) or white (>= 245)
- Uses PIL to efficiently sample image colors
- Gets image position on page via get_image_rects()
- Integrates with existing preprocessing pipeline
- Adds covering_images to page metadata and quality report
Detection results:
- demo_docs/edit3.pdf: 10 black covering images detected (7 on P1, 3 on P2)
Quality report now includes:
- total_covering_images count
- Per-page covering_images details with bbox, color_type, size
🤖 Generated with [Claude Code](https://claude.com/claude-code)
Co-Authored-By: Claude <noreply@anthropic.com>
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