FreeImage.NET library loader for AnyCPU projects. Attempts to load the platform specific 32-bit/64-bit FreeImage.dll from x86 or x64 subfolders. Compile with https://sourceforge.net/p/freeimage/svn/HEAD/tree/FreeImage/trunk/Wrapper/FreeImage.NET/cs/Library/

FreeImageLoader.cs

using System;
using System.IO;
using System.Runtime.InteropServices;

namespace FreeImageAPI
{
    public static partial class FreeImage
    {
        private static readonly bool is64BitProcess = (IntPtr.Size == 8);

        static FreeImage()
        {
            var basePath = Path.GetDirectoryName(new Uri(typeof(FreeImage).Assembly.CodeBase).LocalPath);
            var platformPath = Path.Combine(basePath, is64BitProcess ? "x64" : "x86");

            SetDllDirectory(platformPath);
            LoadLibrary(Path.Combine(platformPath, FreeImageLibrary));
        }

        [DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
        private static extern IntPtr LoadLibrary(string lpLibFileName);

        [DllImport("kernel32.dll", SetLastError = true, CharSet = CharSet.Auto)]
        private static extern bool SetDllDirectory(string lpPathName);
    }
}