groupdocs-watermark-net 26.6.0

GroupDocs.Watermark for Python via .NET - Add, search and remove watermarks in documents

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GroupDocs.Watermark for Python via .NET is a document-watermarking API for adding, searching, and removing text and image watermarks. Stamp configurable text or image watermarks — with control over position, size, opacity, rotation, alignment, and tiling — then save the result back to the original format; search for and remove existing watermarks (including ones added by other tools) across PDF, Word, Excel, PowerPoint, Visio, email, and image formats through one unified API, with no MS Office or other external software required.

Get Started

pip install groupdocs-watermark-net

from groupdocs.watermark import Watermarker
from groupdocs.watermark.watermarks import TextWatermark, Font

with Watermarker("document.pdf") as watermarker:
    watermark = TextWatermark("CONFIDENTIAL", Font("Arial", 36.0))
    watermark.opacity = 0.5
    watermarker.add(watermark)
    watermarker.save("watermarked.pdf")

How It Works

The package is a self-contained Python wheel that bundles the embedded .NET runtime and every native dependency (SkiaSharp, Aspose.Drawing) needed to load, watermark, render, and save documents. No external software installation is required — just pip install and start watermarking. The wheel works across Python 3.5 – 3.14 on Windows, Linux, and macOS (Intel + Apple Silicon).

Features

• Text watermarks — configurable font, foreground/background color, opacity, rotation, and alignment.
• Image watermarks — from a file or an in-memory stream, with scaling, opacity, and positioning.
• Positioning & sizing — absolute coordinates, horizontal/vertical alignment, margins, scale-to-parent sizing, and rotation.
• Tiling — repeat a watermark across the page with configurable tile lines and spacing.
• Search — find existing watermarks by text, image, color, size, or rotation, combined with AND/OR/NOT criteria.
• Remove — delete found watermarks individually or in batches and save the cleaned document.
• Document introspection — read format, page count, and per-page dimensions before processing.
• Previews — render pages to PNG/JPEG/BMP images via a page-stream callback.
• Cross-Platform — Windows x64/x86, Linux x64, macOS x64/ARM64.

Common Tasks

• Stamp a "CONFIDENTIAL" text watermark across every page of a PDF and save it back
• Add a semi-transparent logo image watermark to a Word or PowerPoint document
• Tile a watermark diagonally across a page
• Search a document for an existing watermark by its text and remove it
• Read a document's format and page count before processing
• Render watermarked pages to images for a preview UI

Supported File Formats

For a complete list, see supported formats.

Category	Formats
Word Processing	DOC, DOCX, DOCM, DOT, DOTX, RTF, ODT, OTT
Spreadsheets	XLS, XLSX, XLSM, XLSB, ODS
Presentations	PPT, PPTX, PPTM, PPS, PPSX, ODP
Fixed-Layout	PDF
Diagrams	VSD, VSDX, VSS, VST, VDX
Email	MSG, EML, EMLX
Images	BMP, JPG, JPEG, PNG, GIF, TIFF, WEBP

Examples

Add a text watermark

from groupdocs.watermark import Watermarker
from groupdocs.watermark.watermarks import TextWatermark, Font, Color

with Watermarker("document.pdf") as watermarker:
    watermark = TextWatermark("CONFIDENTIAL", Font("Arial", 48))
    watermark.foreground_color = Color.red
    watermark.opacity = 0.5
    watermark.rotate_angle = -45
    watermarker.add(watermark)
    watermarker.save("watermarked.pdf")

Add an image watermark

from groupdocs.watermark import Watermarker
from groupdocs.watermark.watermarks import ImageWatermark, SizingType

with Watermarker("document.docx") as watermarker:
    watermark = ImageWatermark("logo.png")
    watermark.sizing_type = SizingType.SCALE_TO_PARENT_DIMENSIONS
    watermark.scale_factor = 0.5
    watermark.opacity = 0.7
    watermarker.add(watermark)
    watermarker.save("watermarked.docx")

Tile a watermark across the page

from groupdocs.watermark import Watermarker
from groupdocs.watermark.watermarks import TextWatermark, Font, TileOptions, TileType

with Watermarker("document.pdf") as watermarker:
    watermark = TextWatermark("DRAFT", Font("Arial", 19))
    tile = TileOptions()
    tile.tile_type = TileType.STRAIGHT           # repeat across the page
    watermark.tile_options = tile
    watermark.opacity = 0.3
    watermarker.add(watermark)
    watermarker.save("tiled.pdf")

Search for and remove a watermark

from groupdocs.watermark import Watermarker
from groupdocs.watermark.search.search_criteria import TextSearchCriteria

with Watermarker("watermarked.pdf") as watermarker:
    criteria = TextSearchCriteria("CONFIDENTIAL")     # also: ImageSearchCriteria(...)
    possible = watermarker.search(criteria)
    print("found:", len(possible))
    for wm in possible:
        print(wm.text, wm.x, wm.y)
    watermarker.remove(possible)                       # remove the whole collection
    watermarker.save("clean.pdf")

Read document info

from groupdocs.watermark import Watermarker

with Watermarker("document.pdf") as watermarker:
    info = watermarker.get_document_info()
    print("format:", info.file_type)
    print("pages:", info.page_count)

Watermark from / to a binary stream

import io
from groupdocs.watermark import Watermarker
from groupdocs.watermark.watermarks import TextWatermark, Font

with open("document.pdf", "rb") as src:
    with Watermarker(src) as watermarker:
        watermarker.add(TextWatermark("CONFIDENTIAL", Font("Arial", 36)))
        buffer = io.BytesIO()
        watermarker.save(buffer)          # BytesIO is updated after save
        data = buffer.getvalue()

AI Agent & LLM Friendly

This package is designed for seamless integration with AI agents, LLMs, and automated code generation tools.

• AGENTS.md in the package — AI coding assistants (Claude Code, Cursor, GitHub Copilot) auto-discover the API surface, usage patterns, and troubleshooting tips from the installed package
• MCP server — connect your AI tool to GroupDocs documentation for on-demand API lookups:

  { "mcpServers": { "groupdocs-docs": { "url": "https://docs.groupdocs.com/mcp" } } }
  

• Machine-readable docs — full documentation available as plain text for RAG and LLM context:
  • Single file: https://docs.groupdocs.com/watermark/python-net/llms-full.txt
  • Per page: append .md to any docs URL

Evaluation Mode

The API works without a license in evaluation mode, with these limitations:

• Output is restricted: PDF output carries an evaluation watermark and other formats show an equivalent evaluation mark.
• A page/document-count cap applies to processed documents.

To remove these limitations, apply a license or request a temporary license:

from groupdocs.watermark import License
License().set_license("path/to/license.lic")

Or set the environment variable (auto-applied at import):

export GROUPDOCS_LIC_PATH="path/to/license.lic"

Troubleshooting

Issue	Platform	Fix
Evaluation watermark on output	All	Apply a license — License().set_license(...) or set GROUPDOCS_LIC_PATH
System.Drawing.Common is not supported	Linux/macOS	apt-get install libgdiplus (Linux) or brew install mono-libgdiplus (macOS)
The type initializer for 'Gdip' threw an exception	macOS	brew install mono-libgdiplus
Garbled text / missing fonts in output	Linux	apt-get install ttf-mscorefonts-installer fontconfig && fc-cache -f
DOTNET_SYSTEM_GLOBALIZATION_INVARIANT errors	Linux	Do NOT set this variable. ICU must be available.

System Requirements

• Python 3.5 - 3.14
• Windows x64/x86, Linux x64, macOS x64/ARM64
• No additional software required

More Resources

• Documentation
• Code Examples
• Free Support Forum
• Temporary License

Also available for other platforms: .NET | Java | Node.js

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Product Page | Docs | Demos | API Reference | Blog | Free Support | Temporary License