private static void PadBorders(PNM image, int padding)
{
// copy top and bottom
for (int i = 0; i < padding; i++)
{
Buffer.BlockCopy(image.raster, 3 * (padding * image.Width + padding), image.raster, 3 * (i * image.Width + padding), (image.Width - padding * 2) * 3);
Buffer.BlockCopy(image.raster, 3 * ((image.Height - padding - 1) * image.Width + padding), image.raster, 3 * ((i + image.Height - padding) * image.Width + padding), (image.Width - padding * 2) * 3);
}
// pad right and left
for (int i = 0; i < image.Height - (2 * padding); i++)
{
byte r, g, b;
image.GetPixel(padding, padding + i, out r, out g, out b);
for (int j = 0; j < padding; j++)
{
image.SetPixel(j, padding + i, r, g, b);
}
image.GetPixel(image.Width - padding - 1, padding + i, out r, out g, out b);
for (int j = 0; j < padding; j++)
{
image.SetPixel(image.Width - j - 1, padding + i, r, g, b);
}
}
}
private static PNM ApplyConvolutionMatrixCore(PNM image, float[] matrix, int matrixLength, float weight, float shift)
{
PNM newImage = new PNM(image.Width, image.Height);
int padding = matrixLength / 2;
int maxHeight = newImage.Height - padding;
int maxWidth = newImage.Width - padding;
int width = newImage.Width;
Parallel.For(padding, maxHeight, i =>
{
for (int j = padding; j < maxWidth; j++)
{
float sumR = 0;
float sumG = 0;
float sumB = 0;
// current index position
int position = i * width + j;
for (int m = 0; m < matrixLength; m++)
{
for (int n = 0; n < matrixLength; n++)
{
byte r, g, b;
image.GetPixel(position - ((padding - m) * width) - (padding - n), out r, out g, out b);
float coeff = matrix[(m * matrixLength) + n];
sumR += (r * coeff * weight);
sumG += (g * coeff * weight);
sumB += (b * coeff * weight);
}
}
newImage.SetPixel(position, Coerce(sumR + shift), Coerce(sumG + shift), Coerce(sumB + shift));
}
});
return(newImage);
}
internal static void SaveFile(PNM bitmap, FileStream stream)
{
bitmap.WriteLongHeader("P5", stream);
for (int i = 0; i < bitmap.Height * bitmap.Width; i++)
{
byte r,g,b;
bitmap.GetPixel(i, out r, out g, out b);
byte pixel = RGBToLuminosity(r, g, b);
stream.WriteByte(pixel);
}
}
internal static void SaveFile(PNM bitmap, FileStream stream)
{
bitmap.WriteLongHeader("P5", stream);
for (int i = 0; i < bitmap.Height * bitmap.Width; i++)
{
byte r, g, b;
bitmap.GetPixel(i, out r, out g, out b);
byte pixel = RGBToLuminosity(r, g, b);
stream.WriteByte(pixel);
}
}
private static void PadCorners(PNM image, int padding)
{
byte r, g, b;
// pad top left
image.GetPixel(padding, padding, out r, out g, out b);
for (int i = 0; i < padding; i++)
{
for (int j = 0; j < padding; j++)
{
image.SetPixel(i, j, r, g, b);
}
}
// pad top right
image.GetPixel(image.Width - padding - 1, padding, out r, out g, out b);
for (int i = image.Width - padding; i < image.Width; i++)
{
for (int j = 0; j < padding; j++)
{
image.SetPixel(i, j, r, g, b);
}
}
// pad bottom left
image.GetPixel(padding, image.Height - padding - 1, out r, out g, out b);
for (int i = 0; i < padding; i++)
{
for (int j = image.Height - padding; j < image.Height; j++)
{
image.SetPixel(i, j, r, g, b);
}
}
// pad bottom right
image.GetPixel(image.Width - padding - 1, image.Height - padding - 1, out r, out g, out b);
for (int i = image.Width - padding; i < image.Width; i++)
{
for (int j = image.Height - padding; j < image.Height; j++)
{
image.SetPixel(i, j, r, g, b);
}
}
}
internal static void SaveFile(PNM bitmap, FileStream stream)
{
bitmap.WriteLongHeader("P6", stream);
for (int i = 0; i < bitmap.Height * bitmap.Width; i++)
{
byte r, g, b;
bitmap.GetPixel(i, out r, out g, out b);
stream.WriteByte(r);
stream.WriteByte(g);
stream.WriteByte(b);
}
}
internal static byte PackBytes(PNM bitmap, int start, int amount)
{
int result = 0;
byte r,g,b;
for(int i = 0; i< amount; i++)
{
bitmap.GetPixel(start + i, out r,out g,out b);
if (ColorToBlack(r, g, b))
result |= (128 >> i);
}
return (byte)result;
}
internal static void SaveFile(PNM bitmap, FileStream stream)
{
bitmap.WriteLongHeader("P6", stream);
for (int i = 0; i < bitmap.Height * bitmap.Width; i++)
{
byte r, g, b;
bitmap.GetPixel(i, out r, out g, out b);
stream.WriteByte(r);
stream.WriteByte(g);
stream.WriteByte(b);
}
}
public static PNM ApplyPointProcessing(this PNM oldImage, Func <byte, byte, byte, Pixel> filter)
{
PNM newImage = new PNM(oldImage.Width, oldImage.Height);
byte r, g, b;
int size = oldImage.Width * oldImage.Height;
for (int i = 0; i < size; i++)
{
oldImage.GetPixel(i, out r, out g, out b);
Pixel pixel = filter(r, g, b);
newImage.SetPixel(i, pixel.Red, pixel.Green, pixel.Blue);
}
;
return(newImage);
}
internal static byte PackBytes(PNM bitmap, int start, int amount)
{
int result = 0;
byte r, g, b;
for (int i = 0; i < amount; i++)
{
bitmap.GetPixel(start + i, out r, out g, out b);
if (ColorToBlack(r, g, b))
{
result |= (128 >> i);
}
}
return((byte)result);
}
public static PNM ApplyHeightMapFunction(this PNM image, int matrixLength, Func <int, int, float[], int, Pixel> func)
{
PNM newImage = PNM.Copy(image);
int padding = matrixLength / 2;
Pad(newImage, padding);
int newImageSize = newImage.Width * newImage.Height;
float[] heightmap = new float[newImageSize];
byte r, g, b;
for (int i = 0; i < newImageSize; i++)
{
newImage.GetPixel(i, out r, out g, out b);
heightmap[i] = PNM.RGBToLuminosity(r, g, b) / 255f;
}
newImage = ApplyHeightMapFunctionCore(newImage.Width, newImage.Height, heightmap, matrixLength, func);
Trim(newImage, padding);
return(newImage);
}
internal static Tuple <float[], float[], float[]> ApplyConvolutionUnbound(PNM image, float[] matrix, int matrixLength)
{
int padding = matrixLength / 2;
int oldHeight = image.Height - (padding * 2);
int oldWidth = image.Width - (padding * 2);
Tuple <float[], float[], float[]> rasters = Tuple.Create(new float[oldHeight * oldWidth],
new float[oldHeight * oldWidth],
new float[oldHeight * oldWidth]);
int maxHeight = image.Height - padding;
int maxWidth = image.Width - padding;
Parallel.For(padding, maxHeight, i =>
{
int index = (i - padding) * oldWidth;
for (int j = padding; j < maxWidth; j++)
{
float sumR = 0;
float sumG = 0;
float sumB = 0;
// current index position
int position = i * image.Width + j;
for (int m = 0; m < matrixLength; m++)
{
for (int n = 0; n < matrixLength; n++)
{
byte r, g, b;
image.GetPixel(position - ((padding - m) * image.Width) - (padding - n), out r, out g, out b);
float coeff = matrix[(m * matrixLength) + n];
sumR += r * coeff;
sumG += g * coeff;
sumB += b * coeff;
}
}
rasters.Item1[index] = sumR;
rasters.Item2[index] = sumG;
rasters.Item3[index] = sumB;
index++;
}
});
return(rasters);
}
