地址x86-64和Windows可移植性问题本库（下）。

LibJPEG is a library that is freely available from the Independent JPEG Group (IJG) at http://www.ijg.org/. Using version 8d of the library, I will address 64-bit portability issues (i.e. 32-bit vs. 64-bit data sizes) and some Windows portability issues. The compile environment is Microsoft Visual Studio 2008 with the compiler warning level set to 4 (/W4). The intent is to be able to compile for Windows (x86 & x64) with no compiler errors or warnings.