/// <summary> Get the image signature for a specific file </summary>
public ImageInfo GetSignature(string sFile)
{
ImageInfo ImageInfo = new ImageInfo {
File = sFile, Section = new SectionInfo[_iGridSize]
};
Bitmap bmp = new Bitmap(sFile);
ImageHelper.BitmapBytes BitmapBytes = new ImageHelper.BitmapBytes(bmp);
ImageInfo.AspectRatio = (int)((float)bmp.Height / (float)bmp.Width * 100);
DateTime dt = DateTime.Now;
for (int iRow = 0; iRow < _iRows; iRow++)
{
for (int iCol = 0; iCol < _iCols; iCol++)
{
Coords Coords = GetSectionCoords(iRow, iCol, _iRows, _iCols, bmp.Width, bmp.Height);
int iSection = (iRow * _iCols) + iCol;
ImageInfo.Section[iSection] = GetHisto(Coords, BitmapBytes);
SectionInfo EdgeVars = GetEdge(Coords, BitmapBytes, false);
ImageInfo.Section[iSection].ChangeCount = EdgeVars.ChangeCount;
ImageInfo.Section[iSection].ChangeDistance = EdgeVars.ChangeDistance;
}
}
TimeSpan duration = DateTime.Now - dt;
Console.WriteLine("GetSignature Duration: " + duration.ToString());
return(ImageInfo);
}
public Bitmap GetTestImage(string sFile)
{
Bitmap bmp = new Bitmap(sFile);
ImageHelper.BitmapBytes BitmapBytes = new ImageHelper.BitmapBytes(bmp);
GetEdge(new Coords {
Left = 0, Top = 0, Bottom = bmp.Height - 1, Right = bmp.Width - 1
}, BitmapBytes, true);
BitmapBytes.UnlockBitmap(true);
return(bmp);
}
/// <summary> Calculate a number representing the difference between it and the pixels around it
/// basically a comparison of the r, g and b of 3 pixels to the bottom right
/// This depends on the calling method cycling through all pixels from left to right and downwards,
/// this prevents having to compare all eight surrounding pixels which would duplicate effort </summary>
public int GetPixelDiff(ImageHelper.BitmapBytes BitmapBytes, int x, int y)
{
int iRGB;
int iDiff = 0;
for (iRGB = 0; iRGB < 3; iRGB++)
{
// Middle Right
iDiff += System.Math.Abs(BitmapBytes.GetPixelPart(x, y, (RGB)iRGB) - BitmapBytes.GetPixelPart(x + 1, y, (RGB)iRGB));
// Bottom Right
iDiff += System.Math.Abs(BitmapBytes.GetPixelPart(x, y, (RGB)iRGB) - BitmapBytes.GetPixelPart(x + 1, y + 1, (RGB)iRGB));
// Bottom Middle
iDiff += System.Math.Abs(BitmapBytes.GetPixelPart(x, y, (RGB)iRGB) - BitmapBytes.GetPixelPart(x, y + 1, (RGB)iRGB));
}
return(iDiff);
}
/// <summary> Get the edge detection values for a section of an image </summary>
/// <param name="Coords">Coords specify section of the image to analyse</param>
/// <param name="bModifyImage">if true change the image to show pattern, for debug purposes</param>
private SectionInfo GetEdge(Coords Coords, ImageHelper.BitmapBytes BitmapBytes, bool bModifyImage)
{
int x, y;
int iPixelCount = 0;
int iPixelDist = 0;
SectionInfo EdgeValues = new SectionInfo();
for (x = Coords.Left; x < Coords.Right - 1; x++)
{
for (y = Coords.Top; y < Coords.Bottom - 1; y++)
{
if (GetPixelDiff(BitmapBytes, x, y) > PIXEL_DIFF_TOLERENCE)
{
iPixelCount++;
iPixelDist += GetDistance(x - Coords.Left, y - Coords.Top);
if (bModifyImage)
{
BitmapBytes.SetPixel(x, y, 255, 255, 255);
}
}
else
if (bModifyImage)
{
BitmapBytes.SetPixel(x, y, 0, 0, 0);
}
}
}
if (iPixelCount != 0 && iPixelDist != 0)
{
iPixelDist /= iPixelCount;
}
EdgeValues.ChangeCount = Convert.ToUInt16((float)iPixelCount / (float)GetPixelCount(Coords) * 100);
int iMaxChange = GetDistance(Coords.Right - Coords.Left, Coords.Bottom - Coords.Top);
EdgeValues.ChangeDistance = Convert.ToUInt16((float)iPixelDist / iMaxChange * 100);
return(EdgeValues);
}
/// <summary> Calculate the colour histogram for this section of the image </summary>
private SectionInfo GetHisto(Coords Coords, ImageHelper.BitmapBytes BitmapBytes)
{
int[] Hue = new int[_iNumBars];
int x, y;
SectionInfo SectionInfo = new SectionInfo();
for (x = Coords.Left; x < Coords.Right - 1; x++)
{
for (y = Coords.Top; y < Coords.Bottom - 1; y++)
{
Color pixel = BitmapBytes.GetHSIFromPoint(x, y);
float fHue = pixel.GetHue();
int iIll = (int)(pixel.GetBrightness() * 100);
int iSat = (int)(pixel.GetSaturation() * 100);
bool bColour = false;
// Check for colour or black and white
// based on various illumination and saturation tolerances
if (iSat > 10)
{
if (iIll > 15 && iIll < 91)
{
if (((100 - iIll) + iSat) > 35)
{
if (iSat + iIll > 25)
{
int iSegment = Convert.ToInt32(Math.Floor(fHue / HUE_MAX * (_iNumBars - 2)));
Hue[iSegment]++;
bColour = true;
}
}
}
}
// If this was b/w store either b or w based on the illumination
if (!bColour)
{
if (iIll > 50)
{
Hue[_iNumBars - 2] += 1;
}
else
{
Hue[_iNumBars - 1] += 1;
}
}
}
}
int iCount;
int iPixelCount = (Coords.Bottom - Coords.Top + 1) * (Coords.Right - Coords.Left + 1);
iPixelCount = GetPixelCount(Coords);
for (iCount = 0; iCount < _iNumBars; iCount++)
{
float fPercent = (float)Hue[iCount] / iPixelCount * 100;
Hue[iCount] = (int)fPercent;
}
SectionInfo.Hues = Hue;
return(SectionInfo);
}
