public static void ImageToFile(ColorFloatImage image, string filename)
{
using (Bitmap B = ImageToBitmap(image))
B.Save(filename);
}
public static ColorFloatImage BitmapToColorFloatImage(Bitmap B)
{
int W = B.Width, H = B.Height;
ColorFloatImage res = new ColorFloatImage(W, H);
if (B.PixelFormat == PixelFormat.Format8bppIndexed)
{
Color[] pi = B.Palette.Entries;
byte[] pal = new byte[1024];
for (int i = 0; i < pi.Length; i++)
{
Color C = pi[i];
pal[i * 4] = C.B;
pal[i * 4 + 1] = C.G;
pal[i * 4 + 2] = C.R;
pal[i * 4 + 3] = C.A;
}
LockBitmapInfo lbi = LockBitmap(B, PixelFormat.Format8bppIndexed, 1);
try
{
for (int j = 0; j < H; j++)
{
for (int i = 0; i < W; i++)
{
int c = lbi.data[lbi.linewidth * j + i];
int b = pal[c * 4];
int g = pal[c * 4 + 1];
int r = pal[c * 4 + 2];
res[i, j] = new ColorFloatPixel()
{
b = b, g = g, r = r, a = 0.0f
};
}
}
}
finally
{
UnlockBitmap(lbi);
}
}
else
{
LockBitmapInfo lbi = LockBitmap(B);
try
{
for (int j = 0; j < H; j++)
{
for (int i = 0; i < W; i++)
{
int b = lbi.data[lbi.linewidth * j + i * 4];
int g = lbi.data[lbi.linewidth * j + i * 4 + 1];
int r = lbi.data[lbi.linewidth * j + i * 4 + 2];
res[i, j] = new ColorFloatPixel()
{
b = b, g = g, r = r, a = 0.0f
};
}
}
}
finally
{
UnlockBitmap(lbi);
}
}
return(res);
}
static GrayscaleFloatImage canny(ColorFloatImage image, int thr_high, int thr_low)
{
int MAX = 255;
GrayscaleFloatImage temp_img = nonmax(image);
float max_value = 0;
for (int y = 0; y < temp_img.Height; y++)
{
for (int x = 0; x < temp_img.Width; x++)
{
if (temp_img[x, y] > max_value)
{
max_value = temp_img[x, y];
}
}
}
float high_value = max_value * thr_high / 1000;
float low_value = max_value * thr_low / 1000;
GrayscaleFloatImage out_img = new GrayscaleFloatImage(image.Width, image.Height);
bool[,] visited_pixels = new bool[image.Width, image.Height];
for (int y = 0; y < temp_img.Height; y++)
{
for (int x = 0; x < temp_img.Width; x++)
{
if (temp_img[x, y] < low_value)
{
visited_pixels[x, y] = true;
out_img[x, y] = 0;
}
else if (temp_img[x, y] > high_value)
{
visited_pixels[x, y] = true;
out_img[x, y] = MAX;
}
}
}
GrayscaleFloatImage dir_img = dir(image);
List <Tuple <int, int> > pixels_list = new List <Tuple <int, int> >();
for (int coord_y = 0; coord_y < temp_img.Height; coord_y++)
{
for (int coord_x = 0; coord_x < temp_img.Width; coord_x++)
{
bool flag = false;
flag = recursive(coord_x, coord_y, visited_pixels, pixels_list, dir_img, temp_img, out_img, ref flag);
if (flag)
{
foreach (var a in pixels_list)
{
out_img[a.Item1, a.Item2] = 0;
}
pixels_list = new List <Tuple <int, int> >();
}
else
{
foreach (var a in pixels_list)
{
out_img[a.Item1, a.Item2] = MAX;
}
pixels_list = new List <Tuple <int, int> >();
}
}
}
return(out_img);
}
static GrayscaleFloatImage nonmax(ColorFloatImage image)
{
int offset = 2;
string mode = "even";
ColorFloatImage temp_image = img_expansion(image, mode, offset);
temp_image = gradient(image, mode);
temp_image = img_expansion(temp_image, mode, offset);
GrayscaleFloatImage gray_grad = temp_image.ToGrayscaleFloatImage();
GrayscaleFloatImage dir_img = dir(image);
GrayscaleFloatImage out_img = new GrayscaleFloatImage(image.Width, image.Height);
float max_value = 0;
for (int y = 0; y < out_img.Height; y++)
{
for (int x = 0; x < out_img.Width; x++)
{
float M = gray_grad[x + offset, y + offset];
if (M > max_value)
{
max_value = M;
}
switch (dir_img[x, y])
{
case 0: // o
//break;
case 64: // ->
if (M < gray_grad[x + offset + 1, y + offset] ||
M < gray_grad[x + offset - 1, y + offset])
{
out_img[x, y] = 0;
}
else
{
out_img[x, y] = M;
}
break;
case 128: // ^
if (M < gray_grad[x + offset, y + offset + 1] ||
M < gray_grad[x + offset, y + offset - 1])
{
out_img[x, y] = 0;
}
else
{
out_img[x, y] = M;
}
break;
case 192: // /
if (M < gray_grad[x + offset + 1, y + offset + 1] ||
M < gray_grad[x + offset - 1, y + offset - 1])
{
out_img[x, y] = 0;
}
else
{
out_img[x, y] = M;
}
break;
case 255: // \
if (M < gray_grad[x + offset - 1, y + offset + 1] ||
M < gray_grad[x + offset + 1, y + offset - 1])
{
out_img[x, y] = 0;
}
else
{
out_img[x, y] = M;
}
break;
}
}
}
float mult = 255 / max_value;
for (int y = 0; y < out_img.Height; y++)
{
for (int x = 0; x < out_img.Width; x++)
{
out_img[x, y] *= mult;
}
}
return(out_img);
}
static ColorFloatImage gradient(ColorFloatImage image, String mode)
{
if (mode != "rep" && mode != "odd" && mode != "even")
{
Console.WriteLine("Wrong edge mode");
return(image);
}
ColorFloatImage temp_image = img_expansion(image, mode, 1);
ColorFloatImage temp_image_x = new ColorFloatImage(image.Width, image.Height);
ColorFloatImage temp_image_y = new ColorFloatImage(image.Width, image.Height);
for (int y = 0; y < temp_image_x.Height; y++)
{
for (int x = 0; x < temp_image_x.Width; x++)
{
temp_image_x[x, y] = temp_image[x + 1, y] + (-1) * temp_image[x, y];
}
}
for (int y = 0; y < temp_image_y.Height; y++)
{
for (int x = 0; x < temp_image_y.Width; x++)
{
temp_image_y[x, y] = temp_image[x, y + 1] + (-1) * temp_image[x, y];
}
}
ColorFloatImage out_img = new ColorFloatImage(image.Width, image.Height);
float max_color_r = 0;
float max_color_g = 0;
float max_color_b = 0;
for (int y = 0; y < image.Height; y++)
{
for (int x = 0; x < image.Width; x++)
{
double r_x = temp_image_x[x, y].r, r_y = temp_image_y[x, y].r;
double g_x = temp_image_x[x, y].g, g_y = temp_image_y[x, y].g;
double b_x = temp_image_x[x, y].b, b_y = temp_image_y[x, y].b;
ColorFloatPixel temp_pixel;
temp_pixel.r = (float)(Math.Sqrt(r_x * r_x + r_y * r_y));
if (temp_pixel.r > max_color_r)
{
max_color_r = temp_pixel.r;
}
temp_pixel.g = (float)(Math.Sqrt(g_x * g_x + g_y * g_y));
if (temp_pixel.g > max_color_g)
{
max_color_g = temp_pixel.g;
}
temp_pixel.b = (float)(Math.Sqrt(b_x * b_x + b_y * b_y));
if (temp_pixel.r > max_color_b)
{
max_color_b = temp_pixel.b;
}
temp_pixel.a = 0;
out_img[x, y] = temp_pixel;
}
}
//contrast increasing block
double multiplier_r = 255 / max_color_r;
double multiplier_g = 255 / max_color_g;
double multiplier_b = 255 / max_color_b;
float mul = 1;
if ((multiplier_r <= multiplier_g) && (multiplier_r <= multiplier_b))
{
mul = (float)multiplier_r;
}
else if (multiplier_g <= multiplier_r && multiplier_g <= multiplier_b)
{
mul = (float)multiplier_g;
}
else if (multiplier_b <= multiplier_r && multiplier_b <= multiplier_g)
{
mul = (float)multiplier_b;
}
for (int y = 0; y < image.Height; y++)
{
for (int x = 0; x < image.Width; x++)
{
out_img[x, y] = out_img[x, y] * mul;
}
}
return(out_img);
}
static ColorFloatImage img_expansion(ColorFloatImage inp_img, String mode, int radius)
{
ColorFloatImage out_img = new ColorFloatImage(inp_img.Width + 2 * radius, inp_img.Height + 2 * radius);
for (int y = radius; y < out_img.Height - radius; y++) //centre part pf image
{
for (int x = 0; x < out_img.Width; x++)
{
if (mode == "rep")//replicate
{
if (x < radius)
{
out_img[x, y] = inp_img[0, y - radius];
}
else if (x >= radius + inp_img.Width)
{
out_img[x, y] = inp_img[inp_img.Width - 1, y - radius];
}
else
{
out_img[x, y] = inp_img[x - radius, y - radius];
}
}
else if (mode == "odd")//odd
{
if (x < radius)
{
out_img[x, y] = 2 * inp_img[0, y - radius] + (-1) * inp_img[radius - x - 1, y - radius];
}
else if (x >= radius + inp_img.Width)
{
out_img[x, y] = 2 * inp_img[inp_img.Width - 1, y - radius] + (-1) * inp_img[radius + 2 * inp_img.Width - x - 1, y - radius];
}
else
{
out_img[x, y] = inp_img[x - radius, y - radius];
}
}
else if (mode == "even")//even
{
if (x < radius)
{
out_img[x, y] = inp_img[radius - x - 1, y - radius];
}
else if (x >= radius + inp_img.Width)
{
out_img[x, y] = inp_img[radius + 2 * inp_img.Width - x - 1, y - radius];
}
else
{
out_img[x, y] = inp_img[x - radius, y - radius];
}
}
}
}
for (int y = 0; y < radius; y++) //upper part of image
{
for (int x = 0; x < out_img.Width; x++)
{
if (mode == "rep")//replicate
{
out_img[x, y] = out_img[x, radius];
}
else if (mode == "odd") // odd
{
out_img[x, y] = 2 * out_img[x, radius] + (-1) * out_img[x, 2 * radius - y - 1];
}
else if (mode == "even") // even
{
out_img[x, y] = out_img[x, 2 * radius - y - 1];
}
}
}
for (int y = inp_img.Height + radius; y < out_img.Height; y++) //lower part of image
{
for (int x = 0; x < out_img.Width; x++)
{
if (mode == "rep")//replicate
{
out_img[x, y] = out_img[x, out_img.Height - radius - 1];
}
else if (mode == "odd")//odd
{
out_img[x, y] = 2 * out_img[x, out_img.Height - radius - 1] + (-1) * out_img[x, 2 * (out_img.Height - radius) - y - 1];
}
else if (mode == "even")//even
{
out_img[x, y] = out_img[x, 2 * (out_img.Height - radius) - y - 1];
}
}
}
return(out_img);
}