PdfNetStack 1.0.0

PdfNetStack

Compress, optimize and edit PDF files in .NET. Pure C#, MIT licensed, no native binaries, no Ghostscript. Created and maintained by Jamal Abdelkhalek at JADEV.

PdfNetStack makes PDFs smaller without changing a single rendered pixel, then proves it: the output is re-read and compared to the source object by object before it is returned. If anything differs, you get your original bytes back.

using PdfNetStack;

var result = await PdfOptimizer.OptimizeFileAsync("manual.pdf", "manual.optimized.pdf");
Console.WriteLine($"{result.Disposition}: saved {result.SavingPercent:F1}%");

Features

• Lossless PDF compression: object streams, compressed cross-reference streams, unused object removal, Flate recompression at level 9, PNG prediction for raw images, duplicate font, image and resource merging.
• Lossless JPEG optimization: Huffman tables rebuilt per image, progressive JPEGs rewritten as baseline, metadata segments dropped. DCT coefficients stay identical.
• Optional lossy JPEG compression: JpegQuality requantizes JPEG images at a libjpeg quality, never finer than the original.
• Built-in equivalence proof on every rewrite, also available on its own as PdfEquivalence.FindDifference to check the output of any PDF tool.
• Editing: open, create, merge, split, reorder, rotate, remove and import pages; document info; bookmarks.
• Encryption: open RC4, AES-128 and AES-256 protected PDFs; write AES-256 or AES-128 with user and owner passwords and permissions.
• Safe on untrusted files: bounded parsing and decoding, decompression bomb limits, fuzz tested. Signed and encrypted files are never rewritten by the optimizer.

Editing

PdfDocument doc = PdfDocument.Open("contract.pdf");
doc.Pages.RemoveAt(0);
doc.Pages[0].Rotate(90);
doc.Pages.Import(PdfDocument.Open("annex.pdf").Pages);
doc.Info.Title = "Signed contract";
doc.Security.Encrypt(userPassword: "read", ownerPassword: "admin");
doc.Save("contract-final.pdf");   // optimized and verified by default

Compatibility

Tested on Windows, Linux and macOS, on .NET Framework 4.8, .NET 8 and .NET 10.

Results

On a real-world corpus of 1,296 PDFs (569 MiB), every optimized file was rendered with PDFium and compared with its original: zero differing pixels, zero verification failures.

Links

• Documentation and source
• Command line tool: PdfNetStack.Tool
• Azure Blob Storage pipeline: PdfNetStack.Azure
• Fidelity and verification method
• Changelog
• Report an issue