C# Threaded image processing

Question

                    for (int x = 0; x < blockCountX; x++)
                    {
                        for (int y = 0; y < blockCountY; y++)
                          


        

Answer 1

1. I think, encapsulating chunk location among image data in a class is not that bad. I can't see any other option.
2. As an optimization, you can grab pixel pointer from image.Scan0 if you don't have any restriction about unsafe operations.
3. Creating a fresh image for each block is not a very clever idea. Pass region of interest to the thread.
4. If you can use .NET Framework 4, use Parallel.ForEach for such usages. If you can't use it, you can use thread pools. I guess your computer does not have (2048 x 2048) / (256 x 256) = 64 core CPU.
5. Updating global hex map after a thread termination may improve performance dramatically. Due to Dictionary is not thread-safe, locking global hex map inner loop within a thread is not good idea.