Conversion and Optimization

Overview

Aspose.PDF FOSS for .NET provides converters for transforming PDFs to HTML, Markdown, SVG, and plain text. The optimization subsystem reduces file size and ensures PDF/A compliance through PdfFormatConversionOptions.

PDF to HTML

PdfToHtmlConverter exports PDF pages as HTML documents.

var converter = new PdfToHtmlConverter();
converter.SaveAsHtml("input.pdf", "output.html");

// Or save each page separately
converter.SaveAllPagesAsHtml("input.pdf", "output_dir");

HtmlSaveOptions provides control over image handling, font embedding, and layout strategy.

PDF to Markdown

PdfToMarkdownConverter exports PDF content as Markdown text.

var converter = new PdfToMarkdownConverter("input.pdf");
converter.SaveAsMarkdown("output.md");

// Single page
converter.SavePageAsMarkdown(1, "page1.md");

PDF to SVG

PdfToSvgConverter renders each page as a scalable vector graphic.

var converter = new PdfToSvgConverter();
converter.SaveAllPagesAsSvg("input.pdf", "output_dir");

PDF to text

PdfToTextConverter extracts plain text from PDF pages.

var converter = new PdfToTextConverter();
converter.SaveAsText("input.pdf", "output.txt");

PDF/A compliance

PdfFormatConversionOptions validates and converts documents to PDF/A standards.

using var doc = Document.Open(pdfBytes);

var options = new PdfFormatConversionOptions(
    "log.xml",
    PdfFormat.PDF_A_1B,
    ConvertErrorAction.Delete);

doc.Convert(options);
doc.Save("pdfa.pdf");

Heading-level control

HeadingLevels configures which heading levels are recognized during HTML or Markdown conversion.

var levels = new HeadingLevels();
levels.AddLevels(1, 3);  // Recognize H1 through H3

Tips and Best Practices

• Use PdfToHtmlConverter for web publishing and PdfToMarkdownConverter for documentation workflows.
• PDF/A conversion may remove features (JavaScript, encryption) that violate the standard — use ConvertErrorAction.Delete or ConvertErrorAction.None.
• For large documents, convert page-by-page to manage memory.
• HtmlSaveOptions controls whether images are embedded inline or saved as external files.
• SVG output is ideal for high-resolution display of individual pages.

Common Issues

FAQ

Which PDF/A profiles are supported?

PDF/A-1A, PDF/A-1B, PDF/A-2A, PDF/A-2B, PDF/A-3A, and PDF/A-3B profiles are supported through PdfFormat enumeration values.

Can I convert a single page to HTML?

Yes. Use PdfToHtmlConverter.SavePageAsHtml.

Does Markdown conversion preserve tables?

The converter attempts to render table structures as Markdown tables, but complex layouts may require post-processing.

API Reference Summary

See Also

• Aspose.PDF for .NET Enterprise Product
• Aspose.PDF for .NET — Enterprise Documentation