SetRasterImageAllocateCallbackメソッド

using Leadtools;
using Leadtools.Codecs;

private void SetRasterImageAllocateCallbackExample()
{
   try
   {
      // Set the LEADTOOLS temporary directory to a value we can watch easily
      RasterDefaults.TemporaryDirectory = Path.Combine(ImagesPath.Path,@"Temp\LEADTOOLS");
      // Install a callback to notify us when LEADTOOLS images are created
      // IMPORTANT: SetRasterImageAllocateCallback is global and not thread safe. It will fire
      // for each image being created after this point, so if the action you are performing in the
      // callback requires synchronzation, add the required code. For what this sample is trying
      // to accomplish, our solution is perfectly safe and no synchronization is needed.
      RasterDefaults.SetRasterImageAllocateCallback(new RasterImageAllocateCallback(MyRasterImageAllocateCallback));

      // We want conventional memory and nothing else
      RasterMemoryFlags flags = RasterMemoryFlags.Conventional | RasterMemoryFlags.NoDisk | RasterMemoryFlags.NoTiled;
      // Create a huge RasterImage
      using(RasterImage img = new RasterImage(flags, 20000, 20000, 24, RasterByteOrder.Bgr, RasterViewPerspective.TopLeft, null, null, 0))
      {
         // Rotate it 90 degrees, this will have a memory size greater than the default
         // size of conventional memory and cause LEADTOOLS to switch to a disk or tiled memory
         // model. In the callback below, we instruct LEADTOOLS to only use conventional memory so the command
         // will throw an out of memory exception as expected.
         Leadtools.ImageProcessing.RotateCommand cmd = new Leadtools.ImageProcessing.RotateCommand();
         cmd.Angle = 90 * 100;
         // Exception will be thrown inside here: No Memory since our callback
         // will be called and we instruct LEADTOOLS to not use disk
         cmd.Run(img);
      }
   }
   catch(Exception ex)
   {
      // Show the error
      Console.WriteLine(ex.Message);
   }
}

private static RasterExceptionCode MyRasterImageAllocateCallback(RasterImageAllocateData data)
{
   Console.WriteLine("Trying to allocate:");
   Console.WriteLine("   Memory: {0}", data.MemoryFlags);
   Console.WriteLine("   Size: {0} by {1}", data.Width, data.Height);
   Console.WriteLine("   BPP: {0}, Order: {1}", data.BitsPerPixel, data.Order);
   Console.WriteLine("   Size: {0}", data.Size);

   // Note, all values beside MemoryFlags are read only and cannot be changed

   // We want conventional memory and nothing else, so change this
   data.MemoryFlags = RasterMemoryFlags.Conventional | RasterMemoryFlags.NoTiled | RasterMemoryFlags.NoDisk;

   // If you remove the code above, the toolkit will most probably switch to disk or tiled memory model
   // and creating this huge image will be successful, however, we only want conventional
   // memory in this example, and out of memory exception is the expected behavior of this
   // example

   // Let LEADTOOLS continue with creating the image process
   // You can return any other value to abort
   return RasterExceptionCode.Success;
}