This openly-documented binary file format  is natively used by Adobe Acrobat and other programs. Use of Acrobat is recommended for viewing / use of data encoded in this format. The technical note at  provides a detailed description of the binary format specification.
 Adobe Systems, Inc., “PDF Reference, sixth edition: Adobe Portable Document Format version 1.7” (2006). Online: http://www.adobe.com/content/dam/Adobe/en/devnet/acrobat/pdfs/pdf_reference_1-7.pdf; accessed July 20, 2016