对gif

				using System;
				using System.IO;
				using FreeImageAPI;
				
				namespace Sample02
				{
					class Program
					{
						static void Main(string[] args)
						{
							// Check if FreeImage.dll is available (can be in %path%).
							if (!FreeImage.IsAvailable())
							{
								Console.WriteLine("FreeImage.dll seems to be missing. Aborting.");
								return;
							}
				
							Sample sample = new Sample();
							sample.Example();
						}
					}
				
					public class Sample
					{
						const string fileName = @"multipaged.tif";
						FIMULTIBITMAP dib = 0;
						Random rand = new Random();
				
						public void Example()
						{
							if (!File.Exists(fileName))
							{
								Console.WriteLine("File not found. Aborting.");
								return;
							}
				
							// Load the multipaged bitmap.
							// 'OpenMultiBitmapEx' tries to find the correct file format, loads the bitmap
							// with default options, with write support and does not use caching.
							dib = FreeImage.OpenMultiBitmapEx(fileName);
				
							// Check whether loading succeeded.
							if (dib.IsNull)
							{
								Console.WriteLine("File could not be loaded. Aborting.");
								return;
							}
				
							// Get the number of bitmaps the multipaged bitmap contains.
							int count = FreeImage.GetPageCount(dib);
				
							// Multipaged bitmaps consist of multiple single FIBITMAPs
							FIBITMAP page = 0;
				
							// There are bitmaps we can work with.
							if (count > 0)
							{
								// Lock a random bitmap to work with.
								page = FreeImage.LockPage(dib, rand.Next(0, count));
							}
				
							// Check whether locking succeeded.
							if (page.IsNull)
							{
								// Locking failed. Unload the bitmap and return.
								FreeImage.CloseMultiBitmapEx(ref dib);
								return;
							}
				
							// Get a list of locked pages. This can be usefull to check whether a page has already been locked.
							int[] lockedPages = FreeImage.GetLockedPages(dib);
				
							// Lets modify the page.
							if (FreeImage.AdjustGamma(page, 2d))
							{
								Console.WriteLine("Successfully changed gamma of page {0}.", lockedPages[0]);
							}
							else
							{
								Console.WriteLine("Failed to adjust gamma ...");
							}
				
							// Print out the list of locked pages
							foreach (int i in lockedPages)
								Console.WriteLine("Page {0} is locked.", i);
				
							// Use 'UnlockPage' instead of 'Unload' to free the page. Set the third parameter to 'true'
							// so that FreeImage can store the changed page within the multipaged bitmap.
							FreeImage.UnlockPage(dib, page, true);
				
							// Retieve the list again to see whether unlocking succeeded.
							lockedPages = FreeImage.GetLockedPages(dib);
				
							// No output should be produced here.
							foreach (int i in lockedPages)
								Console.WriteLine("Page {0} is still locked.", i);
				
							// If there are more than one page we can swap them
							if (count > 1)
							{
								if (!FreeImage.MovePage(dib, 1, 0))
								{
									Console.WriteLine("Swapping pages failed.");
								}
							}
				
							if (count > 2)
							{
								// Lock page 2
								page = FreeImage.LockPage(dib, 2);
								if (!page.IsNull)
								{
									// Clone the page for later appending
									FIBITMAP temp = FreeImage.Clone(page);
				
									// Unlock the page again
									FreeImage.UnlockPage(dib, page, false);
				
									// Delete the page form the multipaged bitmap
									FreeImage.DeletePage(dib, 2);
				
									// Append the clone again
									FreeImage.AppendPage(dib, temp);
				
									// Check whether the number of pages is still the same
									Console.WriteLine("Pages before: {0}. Pages after: {1}", count, FreeImage.GetPageCount(dib));
				
									// Unload clone to prevent memory leak
									FreeImage.UnloadEx(ref temp);
								}
							}
				
							// We are done and close the multipaged bitmap.
							if (!FreeImage.CloseMultiBitmapEx(ref dib))
							{
								Console.WriteLine("Closing bitmap failed!");
							}
						}
					}
				}