Portable Document Format (PDF)

The Portable Document Format (PDF). PDF was developed by the Adobe Corporation to allow the exchange and viewing of electronic documents easily and reliably, independent of the environment in which they were created. This format lets you compress large documents.

 It is possible to speed up the loading of large PDF files. For more information, refer to Using Filter Data to Speed up Loading Large Files.

LEADTOOLS can read and write several versions of PDF. The following table summarizes the support:

The PDF Filter supports loading encrypted PDF files with 40bit RC4, 128bit RC4, 128bit AES and 256AES v3.0 encryption.

The PDF Filter supports saving PDF/A format. To save files as PDF/A-1b, the ESO2_PDFA_PROFILE flag should be set in the SAVEFILEOPTION structure. PDF/A does not support all compression formats (see https://www.pdfa.org/wp-content/until2016_uploads/2011/08/pdf-a_a_look_at_the_technical_side-2b.pdf for more details). Therefore, you cannot use this flag in conjunction with FILE_RAS_PDF_LZW.

This filter can save large images by setting the ESO_PDF_SAVE_LOW_MEMORY_USAGE flag in the SAVEFILEOPTION structure. It can also load files that are stored in memory (memory files). It can both load and save PDF files that are JPEG, LZW, CCITT G1 1D, CCITT G3 2D, or CCITT G4 compressed, or are uncompressed. In addition, this filter supports saving JBIG2 and JPEG2000 compressed data. (Note that JBIG2 is only available for PDF 1.4 or later and JPEG2000 is only available for PDF 1.5 or later.)

In addition, it supports an option that disables the cropping of files (by setting the PDF_DISABLE_CROPPING flag in the FILEPDFOPTIONS structure), and an option that disables the use of CIE colors (by setting the PDF_DISABLE_CIECOLORS flag in the FILEPDFOPTIONS structure). Disabling the use of CIE colors will result in faster loading of PS files.

This filter supports reading and writing PDF Annotations.

This filter enhances PDF page extraction (avoids producing broken files when PDF files have internal links).

Support for this format is available in the LEADTOOLS PDF Pro, Pro Suite, and the Document and Medical toolkits.

LEADTOOLS supports loading this format as a raster image or as an SVG (Scalable Vector Graphics) document. For more information, refer to L_LoadSvg and Working with SVG.

Saving JBIG2-compressed PDF files requires a LEADTOOLS PDF Pro, Pro Suite, or one of the Document and Medical licenses.

The file constants associated with this file format are:

Required DLL: LTPDF, LTCLR, LFFAX and LTPDFENGINE. The files required for reading PDF and writing PDF are different.  For a listing of the exact DLLs needed, based on the toolkit version, refer to Files To Be Included With Your Application.

*NOTE: When you request file information on a PDF file, FILE_RAS_PDF will always be returned for the file format, regardless of the composition of the PDF file. LEADTOOLS can read PDF documents that are made up of both text and images.  The text and images are rasterized into one raster image for each page of the document. LEADTOOLS can write PDF documents that are made up of raster images only.

Related Formats: PCL - Printer Command Language Format, PLT - PLT / HPGL Format, PS - PostScript Document Format, RTF - Rich Text Format

Platforms

Win32, x64.

NOTE: LEADTOOLS supports writing this file format using the LEADTOOLS Document Writers.  For more information on the LEADTOOLS Document Writers SDK, see Creating Documents Having Different File Formats.