public static PNM Copy(PNM image)
{
PNM newImage = new PNM(image.Width, image.Height);
Buffer.BlockCopy(image.raster, 0, newImage.raster, 0, image.raster.Length);
return(newImage);
}
internal static void Pad(PNM image, int padding)
{
image.raster = PadWithZeros(image.raster, image.Width * 3, image.Height, padding * 3, padding);
image.Width += 2 * padding;
image.Height += 2 * padding;
PadCorners(image, padding);
PadBorders(image, padding);
}
public static PNM ApplyPixelFunction(this PNM image, int matrixLength, Func <PNM, int, Pixel> func)
{
PNM newImage = PNM.Copy(image);
int padding = matrixLength / 2;
Pad(newImage, padding);
newImage = ApplyConvolutionFunctionCore(newImage, matrixLength, func);
Trim(newImage, padding);
return(newImage);
}
internal void ReplaceImage(string path)
{
Stream stream = File.Open(path, FileMode.Open);
Tuple <PNM, PNMFormat> payload = PNM.LoadFileWithFormat(stream);
Image = payload.Item1;
Format = payload.Item2;
undoList.Clear();
Path = path;
}
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.WriteShortHeader("P4", stream);
for (int i = 0; i < bitmap.Height; i++)
{
for (int j = 0; j < bitmap.Width; j += 8)
{
stream.WriteByte(PackBytes(bitmap, i * bitmap.Width + j, UnpackedBits(j, bitmap.Width)));
}
}
}
internal static void SaveFile(PNM bitmap, FileStream stream)
{
bitmap.WriteShortHeader("P4", stream);
for (int i = 0; i < bitmap.Height; i++)
{
for (int j = 0; j < bitmap.Width; j += 8)
{
stream.WriteByte(PackBytes(bitmap, i * bitmap.Width + j,UnpackedBits(j, bitmap.Width)));
}
}
}
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 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);
}
}
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 object Convert(object value, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
PNM pnm = value as PNM;
if (pnm == null)
{
return(null);
}
var bitmap = new WriteableBitmap(pnm.Width, pnm.Height, 96, 96, PixelFormats.Cmyk32, null);
bitmap.WritePixels(new Int32Rect(0, 0, pnm.Width, pnm.Height), pnm.GetCMYK(), pnm.Width * 4, 0);
return(bitmap);
}
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 ApplyConvolutionMatrix(this PNM image, float[] matrix, float weight, float shift)
{
int length = (int)Math.Sqrt(matrix.Length);
if (Math.Pow(length, 2) != matrix.Length || (length / 2) * 2 == length)
{
throw new ArgumentException("matrix");
}
PNM newImage = PNM.Copy(image);
int padding = length / 2;
Pad(newImage, padding);
newImage = ApplyConvolutionMatrixCore(newImage, matrix, length, weight, shift);
Trim(newImage, padding);
return(newImage);
}
// poor man's pixel shader
private static PNM ApplyConvolutionFunctionCore(PNM image, int matrixLength, Func <PNM, int, Pixel> func)
{
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++)
{
// current index position
int position = i * width + j;
newImage.SetPixel(position, func(image, position));
}
});
return(newImage);
}
private static PNM ApplyHeightMapFunctionCore(int imgWidth, int imgHeight, float[] heightmap, int matrixLength, Func <int, int, float[], int, Pixel> func)
{
PNM newImage = new PNM(imgWidth, imgHeight);
int padding = matrixLength / 2;
int maxHeight = imgHeight - padding;
int maxWidth = imgWidth - padding;
int width = imgWidth;
Parallel.For(padding, maxHeight, i =>
{
for (int j = padding; j < maxWidth; j++)
{
// current index position
int position = i * width + j;
newImage.SetPixel(position, func(imgWidth, imgHeight, heightmap, position));
}
});
return(newImage);
}
public static void SaveFile(PNM bitmap, string path, PNMFormat format)
{
using (FileStream stream = File.Open(path, FileMode.Create, FileAccess.Write))
{
switch (format)
{
case PNMFormat.PBM:
RawPBM.SaveFile(bitmap, stream);
break;
case PNMFormat.PGM:
RawPGM.SaveFile(bitmap, stream);
break;
case PNMFormat.PPM:
RawPPM.SaveFile(bitmap, stream);
break;
default:
throw new ArgumentException("format");
}
}
}
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);
}
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 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);
}
private static void MarkPixel(PNM image, int index)
{
int x = index % image.Width;
int y = index / image.Width;
for (int x0 = -1; x0 <= 1; x0++)
{
for (int y0 = -1; y0 <= 1; y0++)
{
if (x0 == 0 && y0 == 0)
{
continue;
}
int currentY = y + y0;
int currentX = x + x0;
if (currentX < 0 || currentX >= image.Width || currentY < 0 || currentY >= image.Height)
{
continue;
}
image.SetPixel(x + x0, y + y0, 0, 255, 0);
}
}
}
//this should be rewritten to ApplyConvolutionFunction
public static PNM ApplyGradientEdgesDetection(this PNM image)
{
PNM workImage = PNM.Copy(image);
Pad(workImage, 1);
Tuple <float[], float[], float[]> xraster = ApplyConvolutionUnbound(workImage, new float[] { -1, 0, 1,
-1, 0, 1,
-1, 0, 1 }, 3);
Tuple <float[], float[], float[]> yraster = ApplyConvolutionUnbound(workImage, new float[] { 1, 1, 1,
0, 0, 0,
-1, -1, -1 }, 3);
PNM newImage = new PNM(image.Width, image.Height);
int size = image.Width * image.Height;
Parallel.For(0, size, i =>
{
byte r = Coerce(Math.Sqrt(Math.Pow(xraster.Item1[i], 2) + Math.Pow(yraster.Item1[i], 2)));
byte g = Coerce(Math.Sqrt(Math.Pow(xraster.Item2[i], 2) + Math.Pow(yraster.Item2[i], 2)));
byte b = Coerce(Math.Sqrt(Math.Pow(xraster.Item3[i], 2) + Math.Pow(yraster.Item3[i], 2)));
newImage.SetPixel(i, r, g, b);
});
return(newImage);
}
public static void SaveFile(PNM bitmap, string path, PNMFormat format)
{
using (FileStream stream = File.Open(path, FileMode.Create, FileAccess.Write))
{
switch (format)
{
case PNMFormat.PBM:
RawPBM.SaveFile(bitmap, stream);
break;
case PNMFormat.PGM:
RawPGM.SaveFile(bitmap, stream);
break;
case PNMFormat.PPM:
RawPPM.SaveFile(bitmap, stream);
break;
default:
throw new ArgumentException("format");
}
}
}
public object Convert(object[] values, Type targetType, object parameter, System.Globalization.CultureInfo culture)
{
PNM pnm = values[0] as PNM;
int? selection = values[1] as int?;
Visibility?visibility = values[2] as Visibility?;
if (pnm == null || selection == null || visibility != Visibility.Visible)
{
return(Binding.DoNothing);
}
double[] rawData;
switch (selection)
{
case 0:
rawData = pnm.GetHistogramLuminosity();
break;
case 1:
rawData = pnm.GetHistogramRed();
break;
case 2:
rawData = pnm.GetHistogramGreen();
break;
case 3:
rawData = pnm.GetHistogramBlue();
break;
default:
return(Binding.DoNothing);
}
return(BuildHistogramGeometry(rawData));
}
public void Undo()
{
image = undoList.Pop();
OnPropertyChanged("Image");
}
public static PNM Copy(PNM image)
{
PNM newImage = new PNM(image.Width, image.Height);
Buffer.BlockCopy(image.raster, 0, newImage.raster, 0, image.raster.Length);
return newImage;
}
internal static void Trim(PNM image, int padding)
{
image.raster = Trim(image.raster, image.Width * 3, image.Height, padding * 3, padding);
image.Width -= 2 * padding;
image.Height -= 2 * padding;
}
internal void SaveImage(string path, PNMFormat format)
{
PNM.SaveFile(Image, path, format);
Path = path;
Format = format;
}
public void Undo()
{
image = undoList.Pop();
OnPropertyChanged("Image");
}
internal void SaveImage()
{
PNM.SaveFile(Image, Path, Format);
Path = path;
}
public static PNM ApplyHarrisDetector(this PNM image)
{
// gaussian window
float[] gaussian = new float[] { 0, 0.01F, 0.02F, 0.01F, 0,
0.01F, 0.06F, 0.1F, 0.06F, 0.01F,
0.02F, 0.1F, 0.16F, 0.1F, 0.02F,
0.01F, 0.06F, 0.1F, 0.06F, 0.01F,
0, 0.01F, 0.02F, 0.01F, 0 };
// greyscale
PNM workImage = PNM.Copy(image).ApplyPointProcessing(Color.ToGrayscale);
Filter.Pad(workImage, 1);
// integrate with prewitt
double[] normalizedWorkImage = workImage.raster.Where((b, idx) => idx % 3 == 0).Select(b => b / 255d).ToArray();
double[] xraster = RunConvolution(normalizedWorkImage, workImage.Width, workImage.Height, Edges.SobelX, 3);
double[] yraster = RunConvolution(normalizedWorkImage, workImage.Width, workImage.Height, Edges.SobelY, 3);
double[] rasterA = new double[xraster.Length];
double[] rasterB = new double[xraster.Length];
double[] rasterC = new double[xraster.Length];
for (int i = 0; i < xraster.Length; i++)
{
rasterA[i] = Math.Pow(xraster[i], 2);
rasterB[i] = Math.Pow(yraster[i], 2);
rasterC[i] = xraster[i] * yraster[i];
}
rasterA = Filter.PadWithZeros(rasterA, image.Width, image.Height, 2, 2);
rasterB = Filter.PadWithZeros(rasterB, image.Width, image.Height, 2, 2);
rasterC = Filter.PadWithZeros(rasterC, image.Width, image.Height, 2, 2);
// calculate the matrices
double[][] matrices = new double[image.Width * image.Height][];
int maxHeight = image.Height + 2;
int maxWidth = image.Width + 2;
int newWidth = image.Width + 4;
int width = image.Width;
for (int i = 2; i < maxHeight; i++)
{
//Parallel.For(2, maxHeight, (i) =>
//{
for (int j = 2; j < maxWidth; j++)
{
// apply convolution
double accumulatorA = 0;
double accumulatorB = 0;
double accumulatorC = 0;
int mi = 0;
for (int x0 = -2; x0 <= 2; x0++)
{
for (int y0 = -2; y0 <= 2; y0++)
{
accumulatorA += gaussian[mi] * rasterA[(i + x0) * newWidth + j + y0];
accumulatorB += gaussian[mi] * rasterB[(i + x0) * newWidth + j + y0];
accumulatorC += gaussian[mi] * rasterC[(i + x0) * newWidth + j + y0];
mi++;
}
}
int realPosition = (i - 2) * width + (j - 2);
matrices[realPosition] = new double[] { accumulatorA, accumulatorB, accumulatorC };
}
//});
}
// do the part 2 and 3
double[] cornerness = new double[image.Width * image.Height];
for (int i = 0; i < matrices.Length; i++)
{
double det = (matrices[i][0] * matrices[i][1]) - (matrices[i][2] * matrices[i][2]);
double trace = matrices[i][0] + matrices[i][1];
double corner = det - (HarrisK * (trace * trace));
if (corner >= HarrisThreshold)
{
cornerness[i] = corner;
}
}
//return ToPNM(cornerness, image.Width, image.Height);
CenteredNonMaximumSuppression(cornerness, image.Width, image.Height, 3);
// draw corners
PNM newImage = PNM.Copy(image);
for (int i = 0; i < cornerness.Length; i++)
{
if (cornerness[i] == 0)
{
continue;
}
MarkPixel(newImage, i);
}
return(newImage);
}
private static void MarkPixel(PNM image, int index)
{
int x = index % image.Width;
int y = index / image.Width;
for (int x0 = -1; x0 <= 1; x0++)
{
for (int y0 = -1; y0 <= 1; y0++)
{
if(x0 == 0 && y0 == 0)
continue;
int currentY = y + y0;
int currentX = x + x0;
if(currentX < 0 || currentX >= image.Width || currentY < 0 || currentY >= image.Height)
continue;
image.SetPixel(x + x0, y + y0, 0, 255, 0);
}
}
}