Using the Library

Working with XpdfRasterizer

The XpdfRasterizer library uses an opaque handle (type PDFHandle) to represent a PDF file. Multiple PDF files can be open simultaneously (each with its own handle).

Any program that uses the library must include the XpdfRasterizer header file:

Using XpdfRasterizer, you can load PDF files and convert pages to images. Typical code looks like this:

Using XpdfRasterizer in a multithreaded application

In a multithreaded application, the pdfInitLibrary function must be called before any other functions are called. Unlike in single-thread applications where this is optional, the pdfInitLibrary call is required in multithreaded applications. Each PDF handle must be used by only one thread. Given that constraint, all XpdfRasterizer functions (other than pdfInitLibrary) are thread-safe.

Compiling & linking on Windows

The XpdfRasterizer library is supplied as a DLL (XpdfRasterizer.dll) and an import library (XpdfRasterizer.lib).

The following instructions are for Microsoft Visual C++ 6. Similar steps should work for other development environments.

1. Add the include file directory: in the "Project Settings" dialog, under the "C/C++" tab, in the "Preprocessor" category, add the library include file directory (....\XpdfRasterizer\include).
2. Add the import library: in the "Project Settings" dialog, under the "Link" tab, in the "General" category, add the library (....\XpdfRasterizer\lib\XpdfRasterizer.lib).
3. Either add the library directory (....\XpdfRasterizer\lib) to your executable search path, or copy XpdfRasterizer.dll into the same directory as your application's executable.

Compiling & linking on Linux

The XpdfRasterizer library is supplied as a shared library (libXpdfRasterizer.so).

When compiling C or C++ code that uses the XpdfRasterizer library, you'll need to supply a "-I" flag pointing to the directory containing the XpdfRasterizer includes. When linking, you'll need to supply a "-L" flag pointing to the directory containing the XpdfRasterizer library, and a "-lXpdfRasterizer" flag to link with the library.

Look at the Makefile in the example code for a complete demonstration.

Before running the application, make sure that the XpdfRasterizer library directory is on the library search path. This this can be done either by setting the LD_LIBRARY_PATH environment variable or by editing the system-wide /etc/ld.so.conf configuration file.

Compiling & linking on Mac OS X

Using XpdfRasterizer on OS X is very similar to using it on Linux. The shared library has a different extension (libXpdfRasterizer.dylib), and you'll need to set the DYLD_LIBRARY_PATH environment variable.

Static library

XpdfRasterizer includes a static library as well as the dynamic library. To use it, include XpdfRasterizerStatic.h in place of XpdfRasterizer.h, and link to XpdfRasterizerStatic.lib (Windows) or libXpdfRasterizer.a (Linux, Mac OS X).

Example code

The XpdfRasterizer library distribution includes a sample program, pdftoimg.c, located in the examples directory. This program demonstrates the use of the various XpdfRasterizer functions. It converts a PDF file to a series of image files, one per page - monochrome/grayscale/color and image file format can be chosen by uncommenting lines in the source file.

To build on Linux, edit the included Makefile and set the XPDFLIBDIR, XPDFINCDIR, and LIB variables according to the instructions inside the Makefile. Then run "make".

To build on Windows, create a Visual C++ project, as described above.