PDFium Component Docs

Compressed властивість

Component: TPdf  ·  Unit: PDFium
Керує тим, чи стискаються потоки у вихідному PDF через FlateDecode, коли викликається SaveAs / Save. Післязбережувальний механізм стиснення сканує серіалізований PDF, замінює будь-які нестиснуті потоки їхніми zlib-deflated еквівалентами та перебудовує xref table. Уже стиснуті потоки проходять без змін

Syntax

property Compressed: Boolean; // default True

Description

Compressed controls whether the next SaveAs (and family) call applies post-write stream compression. When True — the default — PDFiumPas serializes the document through PDFium, then runs a pass that replaces any uncompressed content / metadata streams with FlateDecode-compressed equivalents and rewrites the cross-reference table to reflect the new offsets.

When False, output streams are written as-is. The resulting file is typically 2-10× larger but is human-readable when opened in a text editor, which is useful for debugging content streams, comparing two PDF revisions with diff, or feeding the output into a PDF-syntax-aware tool that prefers uncompressed input.

Setting Compressed changes only the behavior of the next save; the in-memory document is unaffected. A document that was loaded compressed and saved with Compressed := False will decompress on output; a document loaded uncompressed and saved with Compressed := True will compress on output Round-tripping a fully-compressed document with Compressed := True yields a near-identical file size — the engine recognizes pre-compressed streams and does not re-deflate them.

Remarks

Example

// Save an uncompressed copy alongside the compressed original for debugging
begin
  Pdf.Active := True;
  Pdf.Compressed := True;
  Pdf.SaveAs('output.pdf'); // production copy
  Pdf.Compressed := False;
  Pdf.SaveAs('output_debug.pdf'); // human-readable copy
end;

See Also

SaveAs, Save, Active, Password