hanyouqing/watermarker repository overview

⁠Watermarker

Try it online: https://wm.hanyouqing.com/⁠

⁠✨ Features

• 🔒 Privacy & Security: Local processing, no server uploads
• 🌍 Internationalization: Supports Chinese and English interfaces
• 💧 Easy to Use: Complete your first watermark in 5 minutes
• 🎨 Rich Configuration: Text and image watermarks with transparency, rotation, spacing support
• 📱 Responsive Design: Adapts to desktop, tablet, and mobile devices
• ⚡ High Performance: Optimized for large file processing with batch operations
• 🆓 Completely Free: Open source and transparent with no usage restrictions

⁠🎯 Core Features

⁠Watermark Types

• Text Watermarks: Custom text content, fonts, size, color, and natural directional text shadow
• Image Watermarks: Support for PNG, JPG, JPEG, WebP, GIF, BMP formats
• Mixed Watermarks: Support for both text and image watermarks simultaneously
• Dynamic Variables: Built-in placeholders like {date}, {time}, {timezone}, {tz}, {page}, {total}, and {filename} with automatic hierarchy font scaling
• Custom Fonts: Upload and embed local .ttf, .otf, .woff fonts

⁠Watermark Layout & Placement

• 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)

⁠Experimental Features

• Smart Watermark Eraser (Beta):
  • 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

⁠REST API & Swagger Documentation

• Standalone REST API Service (@watermarker/api): High-performance containerized REST API with full feature parity.
• Interactive Swagger UI: Built-in Swagger API documentation at /swagger with OpenAPI 3.0 specification at /openapi.json.
• codeinchq/watermarker Compatibility: Universal /apply endpoint compatible with standard multipart/form-data parameters (image, watermark, ratio, position, padding, format, quality, blur, opacity).
• Dedicated Endpoints: Full suite of REST endpoints for single/batch watermarking, PDF metadata/vector erasing, and image inpainting.

⁠Productivity & Templates

• Watermark Templates: Save, apply, export all or current configuration, and import watermark presets as JSON
• Undo / Redo History: Multi-step history stack with global shortcuts (Ctrl+Z / Ctrl+Y)
• Global Shortcuts: Ctrl+O (Upload), Ctrl+P (Fullscreen preview), Ctrl+S (Export), Ctrl+Z (Undo), Ctrl+Y (Redo)

⁠File Processing & Performance

• 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)
• File Size: Supports files up to 100MB