public int GetHeight( 
   int ImageID
)

using (GdPictureImaging gdpictureImaging = new GdPictureImaging())
{
    int imageID = gdpictureImaging.CreateGdPictureImageFromFile("image.jpg");
 
    // Remove 5% all around the image.
    int height = gdpictureImaging.GetHeight(imageID);
    int width = gdpictureImaging.GetWidth(imageID);
    gdpictureImaging.Crop(imageID, width * 5 / 100, height * 5 / 100, width * 90 / 100, height * 90 / 100);
    
    gdpictureImaging.SaveAsPNG(imageID, "crop.png");
    gdpictureImaging.ReleaseGdPictureImage(imageID);
}

using (GdPictureImaging gdpictureImaging = new GdPictureImaging())
{
    int imageID = gdpictureImaging.CreateGdPictureImageFromFile("image.jpg", false);
 
    // Get the red channel histogram and the image dimensions.
    int[] histo = new int[256];
    gdpictureImaging.HistogramGetRed(imageID, ref histo);
    int count = gdpictureImaging.GetWidth(imageID) * gdpictureImaging.GetHeight(imageID);
 
    gdpictureImaging.ReleaseGdPictureImage(imageID);
 
    // Create an image representing the histogram. 
    // The image has the same width as the histogram and its height is 1000.                
    int histogramID = gdpictureImaging.CreateNewGdPictureImage(256, 1000, 24, Color.White);
    for (int i = 0; i < 256; i++)
    {
        int value = histo[i] * 1000 / count;
        for (int j = 0; j < value; j++)
        {
            gdpictureImaging.PixelSetColor(histogramID, i, j, Color.Red);
        }
    }
 
    gdpictureImaging.SaveAsPNG(histogramID, "histo.png");
    gdpictureImaging.ReleaseGdPictureImage(histogramID);
}