/// <summary>
/// Using depth first search to find all non-white connected components.
/// </summary>
/// <param name="width"></param>
/// <param name="height"></param>
/// <param name="visited"></param>
/// <param name="ccResult"></param>
public static void DFS(int width, int height, ref bool[,] visited, ConnectedComponent ccResult, Bitmap sourceImage)
{
int i = 0;
int j = 0;
try
{
for (i = -1; i <= 1; i++)
{
for (j = -1; j <= 1; j++)
{
if (!(i == 0 && j == 0) &&
width + i >= 0 && width + i < sourceImage.Width &&
height + j >= 0 && height + j < sourceImage.Height &&
!visited[width + i, height + j] &&
calDiff(sourceImage.GetPixel(width, height), sourceImage.GetPixel(width + i, height + j)) <= ConfigParameters.DiffThreshold)
{
visited[width + i, height + j] = true;
ccResult.PointSet.Add(new iPoint(width + i, height + j));
DFS(width + i, height + j, ref visited, ccResult, sourceImage);
}
}
}
}
catch (Exception ecc)
{
throw new Exception(ecc.Message);
}
}
/// <summary>
/// Find all connected-components in the image and return related information.
/// </summary>
/// <param name="sourceImage"></param>
/// <returns></returns>
public static List<ConnectedComponent> findAllConnectedComponents(Bitmap sourceImage)
{
int i = 0, j = 0;
int width = sourceImage.Width;
int height = sourceImage.Height;
// The array which tells whether the point at position[i,j] has been visited.
bool[,] visited = new bool[width, height];
List<ConnectedComponent> ccResult = new List<ConnectedComponent>();
try
{
for (i = 0; i < width; i++)
{
for (j = 0; j < height; j++)
{
if (!judgeWhitePoint(sourceImage.GetPixel(i, j)) && !visited[i, j])
{
visited[i, j] = true;
ConnectedComponent currentCC = new ConnectedComponent();
currentCC.PointSet.Add(new iPoint(i, j));
try
{
DFS(i, j, ref visited, currentCC, sourceImage);
}
catch (Exception ea)
{
throw new Exception(ea.Message);
}
FormatConnectedComponent(currentCC);
ccResult.Add(currentCC);
}
}
}
}
catch (Exception e)
{
throw new Exception(e.Message);
}
return ccResult;
}
/// <summary>
/// Merge different connected components into one.
/// </summary>
/// <param name="cc1"></param>
/// <param name="cc2"></param>
/// <returns></returns>
public static ConnectedComponent mergeConnectedComponents(List<ConnectedComponent> cc)
{
// If there are only one element in the list, return the element directly.
if (cc.Count == 1)
{
return cc[0];
}
ConnectedComponent ccRet = new ConnectedComponent();
int minWidth = int.MaxValue, minHeight = int.MaxValue;
int maxWidth = int.MinValue, maxHeight = int.MinValue;
foreach (ConnectedComponent ccI in cc)
{
minWidth = ccI.Left_Top.Width_Position < minWidth ? ccI.Left_Top.Width_Position : minWidth;
minHeight = ccI.Left_Top.Height_Position < minHeight ? ccI.Left_Top.Height_Position : minHeight;
maxWidth = ccI.Right_Bottom.Width_Position > maxWidth ? ccI.Right_Bottom.Width_Position : maxWidth;
maxHeight = ccI.Right_Bottom.Height_Position > maxHeight ? ccI.Right_Bottom.Height_Position : maxHeight;
foreach (iPoint ponit in ccI.PointSet)
{
ccRet.PointSet.Add(ponit);
}
}
ccRet.Left_Top = new iPoint(minWidth, minHeight);
ccRet.Right_Bottom = new iPoint(maxWidth, maxHeight);
return ccRet;
}
/// <summary>
/// Judge whether two connected components are similar in color.
/// </summary>
/// <param name="c1"></param>
/// <param name="c2"></param>
/// <returns></returns>
private static bool judgeConnectedComponentsSimilar(ConnectedComponent c1, ConnectedComponent c2, Bitmap sourceImage)
{
bool flag = true;
for (int i = 0; i < c1.PointSet.Count && flag; i++)
{
for (int j = 0; j < c2.PointSet.Count && flag; j++)
{
if (calDiff(
sourceImage.GetPixel(c1.PointSet[i].Width_Position, c1.PointSet[i].Height_Position),
sourceImage.GetPixel(c2.PointSet[j].Width_Position, c2.PointSet[j].Height_Position)
) > Config.ConfigParameters.DiffThreshold
)
{
flag = false;
}
}
}
return flag;
}
/// <summary>
/// Judge whether two connected components are near enough.
/// </summary>
/// <param name="c1"></param>
/// <param name="c2"></param>
/// <returns></returns>
private static bool judgeConnectedComponentsNear(ConnectedComponent c1, ConnectedComponent c2)
{
double distance = calculateDistanceBetweenConnectedComponents(c1, c2);
return distance - Config.ConfigParameters.DistanceThreshold < 0.00001 ? true : false;
}
/// <summary>
/// Calculate the size of certain connected component.
/// </summary>
/// <param name="cc"></param>
/// <returns></returns>
private static int calConnectedComponentsSize(ConnectedComponent cc)
{
int width = cc.Right_Bottom.Width_Position - cc.Left_Top.Width_Position;
int height = cc.Right_Bottom.Height_Position - cc.Left_Top.Height_Position;
return width * height;
}
/// <summary>
/// Calculate the distance of two connected components.
/// </summary>
/// <param name="c1"></param>
/// <param name="c2"></param>
/// <returns></returns>
private static double calculateDistanceBetweenConnectedComponents(ConnectedComponent c1, ConnectedComponent c2)
{
double tmp = 0;
double distance = double.MaxValue;
foreach (iPoint point1 in c1.PointSet)
{
foreach (iPoint point2 in c2.PointSet)
{
tmp = calPointDistance(point1, point2);
if (tmp < distance)
{
distance = tmp;
}
}
}
return distance;
}
/// <summary>
/// According to the point information to find the left-top and right-bottom point.
/// </summary>
/// <param name="currentCC"></param>
private static void FormatConnectedComponent(ConnectedComponent currentCC)
{
int minWidth = int.MaxValue;
int maxWidth = int.MinValue;
int minHeight = int.MaxValue;
int maxHeight = int.MinValue;
foreach (iPoint point in currentCC.PointSet)
{
if (point.Width_Position < minWidth)
{
minWidth = point.Width_Position;
}
if (point.Width_Position > maxWidth)
{
maxWidth = point.Width_Position;
}
if (point.Height_Position < minHeight)
{
minHeight = point.Height_Position;
}
if (point.Height_Position > maxHeight)
{
maxHeight = point.Height_Position;
}
}
currentCC.Left_Top = new iPoint(minWidth, minHeight);
currentCC.Right_Bottom = new iPoint(maxWidth, maxHeight);
}
/// <summary>
/// Write one connected component to certain bmp image.
/// </summary>
/// <param name="ccImage"></param>
/// <param name="sourceImage"></param>
public static void write_Single_Connected_Component_To_Bmp(int tIndex, int index, ConnectedComponent ccImage, Bitmap sourceImage)
{
int width = ccImage.Right_Bottom.Width_Position - ccImage.Left_Top.Width_Position;
int height = ccImage.Right_Bottom.Height_Position - ccImage.Left_Top.Height_Position;
Bitmap ccBmp = new Bitmap(width + 1, height + 1, System.Drawing.Imaging.PixelFormat.Format24bppRgb);
Graphics ccGraphics = Graphics.FromImage(ccBmp);
// Set the background color as white.
ccGraphics.Clear(Color.FromArgb(255, 255, 255));
ccGraphics.Dispose();
foreach (iPoint point in ccImage.PointSet)
{
ccBmp.SetPixel(point.Width_Position - ccImage.Left_Top.Width_Position,
point.Height_Position - ccImage.Left_Top.Height_Position,
sourceImage.GetPixel(point.Width_Position, point.Height_Position)
);
}
ccBmp.Save(ConfigParameters.CC_Image_Bmp_Path + tIndex.ToString() + "_" + index.ToString() + ".bmp");
}
public ConnectedComponent(ConnectedComponent _cc)
{
iniParameter(_cc.Left_Top, _cc.Right_Bottom, _cc.PointSet);
}