/// <summary>
/// Return a bitmap that is a thresholded version of the given. The ultimate threashold value is a matter of
/// emperical testing. 175 is used.
/// </summary>
/// <param name="s"></param>
/// <returns></returns>
protected Bitmap Threshold(Bitmap s)
{
// first threshold to the magic number
Bitmap b = new Bitmap(s);
ImageUtility.ThresholdImage(b, 175.0f / 255.0f);
float[] kernel = ImageUtility.GetGaussianBlurKernel(3, 15);
Bitmap b1 = ImageUtility.Convolve(b, kernel, 3);
b.Dispose();
ImageUtility.ThresholdImage(b1, 1.0f / 255.0f);
// return new image
return(b1);
}
/// <summary>
/// Create a new image based on the given sub image with the candidate red eye removed
/// </summary>
/// <param name="b"></param>
public Bitmap ProcessImage(Bitmap b)
{
// temporary images used to remove red eye
Bitmap rednessMask = null, rednessThreshold = null, falseColor = null, noSmallIslands = null, noHoles = null, blured = null;
// the image to return
Bitmap newImage = null;
try
{
// get a CIEMap of the image and the min/max CIE L values for the image
double minL, maxL;
CIELab[] cieMap = this.GetCIELABImage(b, out minL, out maxL);
// get redness mask image
rednessMask = this.GetMaskImage(cieMap, b.Width, b.Height);
// get a threshold of the redness mask
rednessThreshold = this.Threshold(rednessMask);
// create a blob map from the threasholded image
BlobMap blobmap = new BlobMap(rednessThreshold);
// create a false color copy of the thresholded images
falseColor = (Bitmap)rednessThreshold.Clone();
blobmap.ColorIslands(falseColor);
// remove all islands meeting a certain size criteria
noSmallIslands = (Bitmap)rednessThreshold.Clone();
blobmap.RemoveIslands(noSmallIslands);
// create a version with the holes filled
noHoles = this.FillHoles(noSmallIslands);
// get a guassian blurred version of the final mask
float[] kernel = ImageUtility.GetGaussianBlurKernel(3, 15);
blured = ImageUtility.Convolve(noHoles, kernel, 3);
// create new image
newImage = this.GetNewImage(cieMap, // CIE Lab image of the source
minL, maxL, // min/max CIE L* values in the map
blured); // the final mask to be used
// return new image
return(newImage);
}
catch (Exception)
{
}
finally
{
// cleanup any temporaries used
if (rednessMask != null)
{
rednessMask.Dispose();
}
if (rednessThreshold != null)
{
rednessThreshold.Dispose();
}
if (falseColor != null)
{
falseColor.Dispose();
}
if (noSmallIslands != null)
{
noSmallIslands.Dispose();
}
if (noHoles != null)
{
noHoles.Dispose();
}
if (blured != null)
{
blured.Dispose();
}
}
// return new image
return(newImage);
}
