PDFBlackbox (VCL Edition) is a comprehensive collection of native components that help you compress, encrypt, sign and compress PDF documents from your Delphi or Kylix applications. Both symmetric and certificate-based (X.509) encryption and signing is supported. PDFBlackbox supports full range of PDF security operations, including * PDF standard password-based data encryption using MD5 + RC4/40 or RC4/128 algorithms; * PDF certificate-based public key data encryption using RSA algorithm and PKCS#7 format; * certificate-based data signing using SHA1 with RSA algorithms and PKCS#1 or PKCS#7 format; * ZLib compression; * stream-based processing, which lets you handle huge amounts of data without significant memory requirements; * support for PDF format versions 1.3 to 1.6 PDFBlackbox components are a clean-room implementation of PDF format specification, which don't use any third-party libraries for core functionality. VCL edition of PDFBlackbox can be used with Delphi 4-7 and 2005-2006, C++Builder 4-6 and Kylix 2-3.