Reduce redundant code while working with image (delegate application)?

I'm working on a task that includes image processing. I've found out, that I'm repeating one code over and over (DRY alert) and I'm just curious, whether there is a way to avoid it.

The code is :

for (int x = 0; x < image.Width; x++)
{
    for (int y = 0; y < image.Height; y++)
 开发者_如何学C   {
        byte pixelValue = Convert.ToByte(Byte.MaxValue * image.GetPixel(x, y).GetBrightness());
        //Do something with pixelValue
    }
}

The variety of tasks is wide, once I'm creating histogram, then I'm thresholding the image etc.... I feel there might be some solution using delegates, but I only have limited experience with them and clearly this is not the most important to think of.

Can you propose a solution in .NET Framework 2.0 as well?

Thanks

I dont know about 2.0 but in 4.0 it would probably be something along the lines of

public void VisitPixels(Image image, Action<int,int,Pixel> func){
  for (int x = 0; x < image.Width; x++)
  {
    for (int y = 0; y < image.Height; y++)
    {
       func(x,y,image.GetPixel(x,y));
    }
  }
}

If you want a return value it can get a bit more tricky but you can perhaps think of it like either a Map or a Fold

Map

Pseudo:

public T[][] MapPixels<T>(Image image, Func<int,int,Pixel,T> func){
  var ret = new T[image.Width][image.Height];
  for (int x = 0; x < image.Width; x++)
  {
    for (int y = 0; y < image.Height; y++)
    {
          ret[x][y] = func(x,y,image.GetPixel(x,y)));
    }
  }
  return ret;
}

Fold

public T FoldLPixels<T>(Image image, Func<T,Pixel,T> func, T acc){
  var ret = acc;
  for (int x = 0; x < image.Width; x++)
  {
    for (int y = 0; y < image.Height; y++)
    {
          ret = func(ret,image.GetPixel(x,y));
    }
  }
  return ret;
}

You could then for example get an average Brightness like:

var avgBright = FoldLPixels(image, 
                            (a,b)=>a+b.GetBrightness(),
                            0) / (image.Width+image.Height);

You could do it like this:

public static void ProcessPixelValues(Image image, Action<int, int, byte> processPixelValue)
{
    for (int x = 0; x < image.Width; x++)
    {
        for (int y = 0; y < image.Height; y++)
        {
            byte pixelValue = Convert.ToByte(Byte.MaxValue * image.GetPixel(x,         y).GetBrightness());

            processPixelValue(x, y, pixelValue);
        }
    }
}

public static void PrintPixelValuesOfImage(Image image)
{
    Action<int, int, byte> processPixelValue = 
        (x, y, pixelValue) => Console.WriteLine("The pixel value of [{0},{1}] is {2}", x, y, pixelValue);

    ProcessPixelValues(image, processPixelValue);
}

C# 2.0 Code

public delegate void ProcessPixelValueCallback(int x, int y, byte pixelValue);  

public static void ProcessPixelValues(Image image, ProcessPixelValueCallback processPixelValue)
{
    for (int x = 0; x < image.Width; x++)
    {
        for (int y = 0; y < image.Height; y++)
        {
            byte pixelValue = Convert.ToByte(Byte.MaxValue * image.GetPixel(x,         y).GetBrightness());

            processPixelValue(x, y, pixelValue);
        }
    }
}

public static void PrintPixelValuesOfImage(Image image)
{
    ProcessPixelValueCallback processPixelValue = delegate(int x, int y, byte pixelValue)
    {
        Console.WriteLine("The pixel value of [{0},{1}] is {2}", x, y, pixelValue);
    };

    ProcessPixelValues(image, processPixelValue);
}