Layout Modes: Grid Tiling (tile) or Single Watermark (single)
Text Shadow & Directional Lighting: Rotation-aware text shadow projection automatically opposite to watermark angle across Canvas and PDF export
Interactive Drag & Rotate Handle: Freely drag watermarks directly within the PDF and image preview canvas, and rotate using the top circular handle with magnetic snap
Nine-Grid Position Presets: 3x3 interactive Position Grid (Center, Top-Center, Bottom-Center, Center-Left, Center-Right, and 4 Corners) with free-drag percentage coordinates
Multi-Layer Watermarks: Add up to 5 independent text and image watermark layers with automatic #N numbering, first-layer style inheritance, and visibility toggle
Decoupled Mixed-Mode Controls: Independent density, opacity, rotation, and layout settings for text and image in mixed mode
Transform Controls: Opacity (0–100%), free rotation (0–360°), scaling, and density control (default 80% text density)
PDF Watermark Eraser: Accurately erase text watermarks from PDF content streams without losing vector typography or document formatting, with auto-detected repeating watermark candidates
Image Inpainting Eraser: Drag-and-select watermark area or pick location presets on images, seamlessly erasing watermarks via client-side harmonic diffusion and texture inpainting algorithms
Zero-Latency Real-Time Preview: Hardware-accelerated CSS/DOM watermark overlay across both PDF and image previews, delivering 60 FPS jitter-free interactive feedback
Large PDF Optimization: Virtualized thumbnail scrolling (react-window) supporting 800+ page documents with bounded LRU memory management
Single File Processing: Drag-and-drop upload with real-time preview
Batch Processing: Support for batch processing and ZIP download
Format Support: PDF 1.4 - 2.0, Images (PNG, JPG, WebP, GIF, SVG)