public static int[] Extract(Bitmap image)
{
int redPx = 0, whitePx = 0, yellowPx = 0, bluePx = 0, totalPx = 0;
unsafe
{
var bitmapData = image.LockBits(new Rectangle(0, 0, image.Width, image.Height), ImageLockMode.ReadWrite, image.PixelFormat);
var bytesPerPixel = Image.GetPixelFormatSize(image.PixelFormat) / 8;
var heightInPixels = bitmapData.Height;
var widthInBytes = bitmapData.Width * bytesPerPixel;
var ptrFirstPixel = (byte *)bitmapData.Scan0;
Parallel.For(0, heightInPixels, y =>
{
var currentLine = ptrFirstPixel + (y * bitmapData.Stride);
for (var x = 0; x < widthInBytes; x = x + bytesPerPixel)
{
var labColor = LabColor.FromRgb(currentLine[x + 2], currentLine[x + 1], currentLine[x]);
if (Red.DistanceTo(labColor) < ToleranceDistance)
{
redPx++;
}
else if (White.DistanceTo(labColor) < ToleranceDistance)
{
whitePx++;
}
else if (Yellow.DistanceTo(labColor) < ToleranceDistance)
{
yellowPx++;
}
else if (Blue.DistanceTo(labColor) < ToleranceDistance)
{
bluePx++;
}
totalPx++;
}
});
image.UnlockBits(bitmapData);
}
return(new[] { redPx *100 / totalPx, whitePx *100 / totalPx, yellowPx *1000 / totalPx, bluePx *100 / totalPx });
}
public double DistanceTo(LabColor otherColor)
{
return
(Math.Sqrt(Math.Pow(L - otherColor.L, 2) + Math.Pow(A - otherColor.A, 2) + Math.Pow(B - otherColor.B, 2)));
}
