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Parallize elementwise matrix (2dArray) calculations

This is my first question and I'm relatively new to C#. (Excuse my bad English)
I'm writing a template matching algorithm in C# using the .NET Framework with a WindowsForms Application in Visual Studio. Sadly the new indices and ranges functions from C#8.0, especially the range operator (..), didn't get implemented in the .NET Framework. I know there is a workaround for this as you can see in this thread but it is not supported by Microsoft. So I'm searching for another way to parallelize my elementwise 2dArray (matrix) calculations to make my program faster.
In my program, I'm calculating the differential square (ds) of an area (with the size of my template) inside a 2dArray (my image) and a 2dArray (my template). These values a written to a new 2dAary (DS) which holds all differential squares in the corresponding positions to the image. I can search the indices of DS where the differential square is minimal which is equal to the matching position (highest correspondence between template and image) of the template inside the image.
In python the calculation of DS is very quick using the index range operator (:) and will look like this:
H,W = I.shape # read out Height H & Width W from Image I
h,w = T.shape # read out Height h & Width w from Template T
for i in range(H-h+1):
for j in range(W-w+1):
DS[i,j] = np.sum((I[i:i+h,j:j+w] - T)**2)
But in C# I have to make the calculation of DS elementwise therefore it looks like this and takes for ever:
int Tw = template.Width;
int Th = template.Height;
int Iw = image.Width;
int Ih = image.Height;
int d = 0;
int[,] ds = new int[Tw, Th];
int[,] DS = new int[Iw - Tw + 1, Ih - Th + 1];
for (int y = 0; y < Ih - Th + 1; y++)
{
for (int x = 0; x < Iw - Tw + 1; x++)
{
for (int yT = 0; yT < Th; yT++)
{
for (int xT = 0; xT < Tw; xT++)
{
d = I[x + xT, y + yT] - T[xT, yT];
ds[xt, yt] = d * d;
}
}
int sum = ds.Cast<int>().Sum();
DS[x, y] = sum;
}
}
I know that I could use threads but that would be a little complex for me.
Or maybe I could use CUDA with my Nvidia GPU to speed things up a little.
But I am asking you and myself is there another way to parallelize (optimize) my elementwise 2dArray calculations?
I look forward to any help.
Many thanks in advance!!!
EDIT:
Here I have a working example of my code for a .NET Framework Console App. As you can see I make a lot of elementwise 2d and 3d Array calculations which I would like to process in parallel (or perform them faster in any other way):
using System;
using System.Drawing;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace TemplateMatcher_Console
{
class Program
{
public static int[,,] bitmapToMatrix(Bitmap bmp)
{
int[,,] I = new int[bmp.Width, bmp.Height, 3];
for (int y = 0; y < bmp.Height; y++)
{
for (int x = 0; x < bmp.Width; x++)
{
Color pix = bmp.GetPixel(x, y);
I[x, y, 0] = Convert.ToInt32(pix.R);
I[x, y, 1] = Convert.ToInt32(pix.G);
I[x, y, 2] = Convert.ToInt32(pix.B);
}
}
return I;
}
public static int[] indexOfMiniumValue(int[,] matrix)
{
int value = 0;
int minValue = 999999999;
int minFirstIndex = 0;
int minSecondIndex = 0;
int[] ij = new int[2];
for (int i = 0; i < matrix.GetLength(0); i++)
{
for (int j = 0; j < matrix.GetLength(1); j++)
{
value = matrix[i, j];
if (value < minValue)
{
minValue = value;
minFirstIndex = i;
minSecondIndex = j;
}
}
}
ij[0] = minFirstIndex;
ij[1] = minSecondIndex;
return ij;
}
public static void Print2DArray<T>(T[,] matrix)
{
for (int i = 0; i < matrix.GetLength(0); i++)
{
for (int j = 0; j < matrix.GetLength(1); j++)
{
Console.Write(matrix[i, j] + "\t");
}
Console.WriteLine();
}
}
static void Main(string[] args)
{
// Deklaration & Eingabe
Console.WriteLine("Type the filepath for your image and then press Enter");
string im = Console.ReadLine();
Console.WriteLine("\nType the filepath for your template and then press Enter");
string temp = Console.ReadLine();
Bitmap template = new Bitmap(#temp);
Bitmap image = new Bitmap(#im);
int Tw = template.Width;
int Th = template.Height;
int Iw = image.Width;
int Ih = image.Height;
int[,] ds = new int[Tw, Th];
int[,] DS = new int[Iw - Tw + 1, Ih - Th + 1];
int[,,] DS_rgb = new int[Iw - Tw + 1, Ih - Th + 1, 3];
int[] xy = new int[2];
// Verarbeitung
// int[,,] I = Array.ConvertAll(image_I, new Converter<byte, int>(Convert.ToInt32));
int[,,] I = bitmapToMatrix(image);
int[,,] T = bitmapToMatrix(template);
for (int rgb = 0; rgb < 3; rgb++)
{
for (int y = 0; y < Ih - Th + 1; y++)
{
for (int x = 0; x < Iw - Tw + 1; x++)
{
//DS_rgb[x, y, rgb] = (I[x .. x + template.Width, y .. y + template.Height, rgb] - T[0 .. template.Width, 0 .. template.Height, rgb]);
for (int yT = 0; yT < Th; yT++)
{
for (int xT = 0; xT < Tw; xT++)
{
ds[xT, yT] = (I[x + xT, y + yT, rgb] - T[xT, yT, rgb]) * (I[x + xT, y + yT, rgb] - T[xT, yT, rgb]);
}
}
int sum = ds.Cast<int>().Sum();
DS_rgb[x, y, rgb] = sum;
}
}
}
//DS[.., ..] = DS_rgb[.., .., 0] + DS_rgb[.., .., 1] + DS_rgb[.., .., 2];
for (int y = 0; y < Ih - Th + 1; y++)
{
for (int x = 0; x < Iw - Tw + 1; x++)
{
DS[x, y] = DS_rgb[x, y, 0] + DS_rgb[x, y, 1] + DS_rgb[x, y, 2];
}
}
//xy = DS.FindIndex(z => z == Math.Min(DS));
xy = indexOfMiniumValue(DS);
// Ausgabe
// Ausgeben der Matrix DS
/*
Console.WriteLine("\nMatrix with all differtial squares:");
Print2DArray(DS);
*/
Console.WriteLine($"\nPosition of your template in your image (upper left corner): ({xy[0]}, {xy[1]})");
Console.Write("\nPress any key to close the TemplateMatcher console app...");
Console.ReadKey();
}
}
}

Processing image stops mid-loop for no reason c#

I have an image, and I want to take each square of 256X256 pixels, find the mean color, and draw that square with said color.
Problem: it seems that after the first square the processing suddenly stops, but after following the program I can see the indexes are just fine. I have no idea if the problem lies with file writing in my computer system, or a wrong use of the "Bitmap" class functions.
original:
result:
code:
public const int big =256;
public const int small = 16;
static void Main(string[] args)
{
Bitmap bt = new Bitmap(#"C:\Users\mishe\Desktop\00_sorted images - training\general shores\agulhas_oli_2016146_lrg.jpg");
Bitmap bt2 = bt;
Color MeanColor;
double r = 0;
double g = 0;
double b = 0;
int i = 0;
int j = 0;
//big loop to go over all image
for (i = 0; i < bt.Height-257; i+=256)
{
for (j = 0; j < bt.Width-257; j+=256)
{
/////////////////////////////
//small loop on 1 square to get the mean color of the area
for (int x = i; x < big; x++)
{
for (int y = j; y < big; y++)
{
r += bt.GetPixel(x, y).R;
g += bt.GetPixel(x, y).G;
b += bt.GetPixel(x, y).B;
}
}
/////////////////////////////
r = r / Math.Pow(big, 2);
g = g / Math.Pow(big, 2);
b = b / Math.Pow(big, 2);
MeanColor = Color.FromArgb((int)r, (int)g, (int)b);
/////////////////////////////
//small loop on the same square to set the color
for (int x = i; x < big; x++)
{
for (int y = j; y < big; y++)
{
bt2.SetPixel(x, y, MeanColor);
}
}
/////////////////////////////
}
}
bt2.Save(#"C:\Users\mishe\Desktop\compressed image.jpg", ImageFormat.Jpeg);
}

This line:
//small loop on 1 square to get the mean color of the area
for (int x = i; x < big; x++)
After the first square, x will be 256, so it won't do the small loop.
I think you want:
for (int x = i; x < i + big; x++)
Or your small loop could be:
for (int x = 1; x < big; x++)
and then add the large and small values inside the loop:
r += bt.GetPixel(i + x, j + y).R;

Trying to perform 2D Cross correlation on 2 images without using Matlab/Numpy/etc

I am trying to perform Cross Correlation on these 2 images in C#:
Image, Template
Matlab says the result is supposed to look like: Matlab result
But this is my result: My result
Here is my Cross Correlation function:
public static Signal2D CrossCorrelation2D(Signal2D signal, Signal2D pulse) {
return InverseFFT2D(FFT2D(signal) * FFT2D(pulse).GetConjugate());
}
Here is my FFT2D:
public static Signal2D FFT2D(Signal2D signal) {
Signal2D result = new Signal2D(signal.Height, signal.Width);
for (int i = 0; i < result.Height; i++)
result[i] = new ComplexNumber[signal[i].Length];
//rows
for (int n = 0; n < signal.Height; n++) {
result[n] = FFT(signal[n]);
}
//columns
for (int i = 0; i < signal[0].Length; i++) {
ComplexNumber[] col = new ComplexNumber[signal.Height];
for (int j = 0; j < col.Length; j++) {
col[j] = result[j][i];
}
col = FFT(col);
for (int j = 0; j < col.Length; j++) {
result[j][i] = col[j];
}
}
return result;
}
Here is my FFT:
public static Signal FFT(Signal signal) {
int N = signal.Length;
if (N == 1)
return signal;
if ((N & (N - 1)) != 0)
throw new ArgumentOutOfRangeException("signal length must be a power of 2");
Signal evenArr = new Signal(N / 2);
Signal oddArr = new Signal(N / 2);
for (int i = 0; i < N / 2; i++) {
evenArr[i] = signal[2 * i];
}
evenArr = FFT(evenArr);
for (int i = 0; i < N / 2; i++) {
oddArr[i] = signal[2 * i + 1];
}
oddArr = FFT(oddArr);
Signal result = new Signal(N);
for (int k = 0; k < N / 2; k++) {
double w = -2.0 * k * Math.PI / N;
ComplexNumber wk = new ComplexNumber(Math.Cos(w), Math.Sin(w));
ComplexNumber even = evenArr[k];
ComplexNumber odd = oddArr[k];
result[k] = even + (wk * odd);
result[k + N / 2] = even - (wk * odd);
}
return result;
}
Here is my Signal multiplication (using pointwise multiplication):
public static Signal2D operator* (Signal2D a, Signal2D b) {
if (a.Height != b.Height || a.Width != b.Width)
throw new ArgumentException("Sizes must be equal");
Signal2D result = new Signal2D(a.Height, a.Width);
for (int y = 0; y < a.Height; y++) {
for (int x = 0; x < a.Width; x++) {
result[y][x] = a[y][x] * b[y][x];
}
}
return result;
}
Any help is appreciated, thanks.
Edit: I left the matlab image at the original size of 1023 by 1023 and overlayed my result. It looks like I may already be at the result, I am just not sure how Matlab pads the image. Overlayed results (The red is the white part from my result, the grey is the black part from my result. Black/white is from Matlab)

Rotating matrices

Objectives
Imagine that, we have matrix like
a11 a12 a13
a21 a22 a23
a31 a32 a33
What I want to do is, from textbox value rotate this matrix so that, for example if I write 2 and press rotate, program must keep both diagonal values of matrix (in this case a11, a22, a33, a13, a31) and rotate 2 times clockwise other values. So result must be like
a11 a32 a13
a23 a22 a21
a31 a12 a33
It must work for all N x N size matrices, and as you see every 4 rotation takes matrix into default state.
What I've done
So idea is like that, I have 2 forms. First takes size of matrix (1 value, for example if it's 5, it generates 5x5 matrix). When I press OK it generates second forms textbox matrix like that
Form 1 code
private void button1_Click(object sender, EventArgs e)
{
int matrixSize;
matrixSize = int.Parse(textBox1.Text);
Form2 form2 = new Form2(matrixSize);
form2.Width = matrixSize * 50 + 100;
form2.Height = matrixSize *60 + 200;
form2.Show();
//this.Hide();
}
Form 2 code generates textbox matrix from given value and puts random values into this fields
public Form2(int matrSize)
{
int counter = 0;
InitializeComponent();
TextBox[] MatrixNodes = new TextBox[matrSize*matrSize];
Random r = new Random();
for (int i = 1; i <= matrSize; i++)
{
for (int j = 1; j <= matrSize; j++)
{
var tb = new TextBox();
int num = r.Next(1, 1000);
MatrixNodes[counter] = tb;
tb.Name = string.Format("Node_{0}{1}", i, j);
Debug.Write(string.Format("Node_{0}{1}", i, j));
tb.Text = num.ToString();
tb.Location = new Point(j * 50, i * 50);
tb.Width = 30;
tb.Visible = true;
this.splitContainer1.Panel2.Controls.Add(tb);
counter++;
}
}
}
Form 2 has 1 textbox for controlling rotation (others are generated on the fly, programmatically). What I want to do is, when I enter rotation count and press Enter on this textbox, I want to rotate textbox matrix as I explained above. Can't figure out how to do it.

Copy both diagonals to separate arrays, then rotate your matrix and replace diagonals. Below code shows each step:
class Program
{
static void Main(string[] args)
{
int matrixSize = 3;
string[,] matrix = new string[matrixSize,matrixSize];
//create square matrix
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
matrix[x, y] = "a" + (x + 1).ToString() + (y + 1).ToString();
}
}
Console.WriteLine(Environment.NewLine + "Base square matrix");
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(matrix[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
//copy diagonals
string[] leftDiagonal = new string[matrixSize];
string[] rightDiagonal = new string[matrixSize];
for (int x = 0; x < matrixSize; x++)
{
leftDiagonal[x] = matrix[x, x];
rightDiagonal[x] = matrix[matrixSize - 1 - x, x];
}
Console.WriteLine(Environment.NewLine + "Diagonals");
for (int x = 0; x < matrixSize; ++x)
{
Console.Write(leftDiagonal[x] + " " + rightDiagonal[x] + Environment.NewLine);
}
Console.ReadKey();
//rotate matrix
string[,] rotatedMatrix = new string[matrixSize, matrixSize];
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
rotatedMatrix[x, y] = matrix[matrixSize - y - 1, x];
}
}
Console.WriteLine(Environment.NewLine + "Rotated");
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(rotatedMatrix[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
//rotate matrix again
string[,] rotatedMatrixAgain = new string[matrixSize, matrixSize];
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
rotatedMatrixAgain[x, y] = rotatedMatrix[matrixSize - y - 1, x];
}
}
Console.WriteLine(Environment.NewLine + "Rotated again");
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(rotatedMatrixAgain[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
//replace diagonals
for (int x = 0; x < matrixSize; x++)
{
rotatedMatrixAgain[x, x] = leftDiagonal[x];
rotatedMatrixAgain[matrixSize - 1 - x, x] = rightDiagonal[x];
}
Console.WriteLine(Environment.NewLine + "Completed" + Environment.NewLine);
for (int x = 0; x < matrixSize; x++)
{
for (int y = 0; y < matrixSize; y++)
{
Console.Write(rotatedMatrixAgain[x, y] + " ");
}
Console.Write(Environment.NewLine);
}
Console.ReadKey();
}
}

I don't know C#, so I can only give a suggestion in pseudocode:
Input: An N by N matrix in
Output: The input matrix rotated as described in the OP out
for i = 1 to N
for j = 1 to N
if N - j != i and i != j // Do not change values on either diagonal
out[j][N-i] = in[i][j]
else
out[i][j] = in[i][j]
Disclaimer: This algorithm is untested. I suggest you use a debugger to check that it works as you want.

This seems like quite an unorthodox UI presentation, but you're not too far off in terms of being able to achieve your functionality. Instead of a linear array, a rectangular array will make your job much easier. The actual rotation could be implemented with a for loop repeating a single rotation (which would be implemented as in the case 1 code), but I've decided to combine them into the four possible cases. This actually allows you to enter a negative number for number of rotations. Which reminds me, you really should do more error checking. At least protect against int.Parse throwing an exception both places it's used (with a try catch block or by switching to int.TryParse) and make sure it returns a meaningful number (greater than 0, possibly set a reasonable maximum other than int.MaxValue) for matrixSize in button1_Click.
namespace RotatingMatrices
{
public class Form2 : Form
{
// note these class fields
private TextBox[,] matrixNodes;
private int matrixSize;
public Form2(int matrSize)
{
InitializeComponent();
// note these inits
matrixSize = matrSize;
matrixNodes = new TextBox[matrixSize, matrixSize];
Random r = new Random();
// note the new loop limits
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
var tb = new TextBox();
int num = r.Next(1, 1000);
// note the change in indexing
matrixNodes[i,j] = tb;
tb.Name = string.Format("Node_{0}_{1}", i, j);
Debug.Write(string.Format("Node_{0}_{1}", i, j));
tb.Text = num.ToString();
tb.Location = new Point(j * 50, i * 50);
tb.Width = 30;
tb.Visible = true;
this.splitContainer1.Panel2.Controls.Add(tb);
}
}
}
private void buttonRotate_Click(object sender, EventArgs e)
{
string[,] matrix = new string[matrixSize, matrixSize];
int rotations = (4 + int.Parse(textBoxRotations.Text)) % 4; // note the addition of and mod by 4
switch(rotations)
{
case 1: // rotate clockwise
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrix[j, matrixSize - i - 1] = matrixNodes[i, j].Text;
}
}
break;
case 2: // rotate 180 degrees
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrix[i, j] = matrixNodes[matrixSize - i - 1, matrixSize - j - 1].Text;
}
}
break;
case 3: // rotate counter-clockwise
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrix[i, j] = matrixNodes[j, matrixSize - i - 1].Text;
}
}
break;
default: // do nothing
return;
}
// restore diagonals
for(int i = 0; i < matrixSize; i++)
{
matrix[i, i] = matrixNodes[i, i].Text;
matrix[i, matrixSize - i - 1] = matrixNodes[i, matrixSize - i - 1].Text;
}
// write strings back to text boxes
for (int i = 0; i < matrixSize; i++)
{
for (int j = 0; j < matrixSize; j++)
{
matrixNodes[i, j].Text = matrix[i, j];
}
}
}
}
}

I decided to tackle the issue using a listView instead of a text box, which makes the logic easier for me. Using this method, I was able to think of the matrix as successive boxes. I start on the outside and move in toward the middle, changing the size of my box each time.
Also, rather than using two forms, I use one. At the top I have a textbox where the user enters the size they want the array to be, and a button labeled "Fill" (button2). And at the bottom I have a textbox where the user enters the degree of rotation. When they click "Rotate," it kicks off a process of adding values to linked lists, combining and shifting the list, and then writing back out to the matrix. I'm sure I made it more convoluted than it has to be, but it was a great learning exercise.
After looking over jerry's code above, I think I'm going to look into rectangular arrays. :)
using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
namespace Recycle
{
public partial class Form1 : Form
{
public int size;
public LinkedList<string> topRight = new LinkedList<string>();
public LinkedList<string> bottomLeft = new LinkedList<string>();
public LinkedList<string> myMatrix = new LinkedList<string>();
public LinkedList<string> shiftMatrix = new LinkedList<string>();
public Form1()
{
InitializeComponent();
}
private void button2_Click(object sender, EventArgs e)
{
listView1.Clear();
size = int.Parse(textBox2.Text);
int c = 0;
int q = 0;
int w = 0;
string[] content = new string[size];
Random rnd = new Random();
for (c = 0; c < size; c++)
{
listView1.Columns.Add("", 25);
}
for (q = 0; q < size; q++)
{
for (w = 0; w < size; w++)
{
content[w] = rnd.Next(9,100).ToString();
}
ListViewItem lvi = new ListViewItem(content);
listView1.Items.Add(lvi);
}
}
public bool iseven(int size)
{
if (size % 2 == 0)
{
return true;
}
else
{
return false;
}
}
public void button1_Click(object sender, EventArgs e)
{
if (listView1.Items.Count < 3)
{
MessageBox.Show("Matrix cannot be rotated.");
return;
}
bool even = false;
int shift = int.Parse(textBox1.Text); //amount to shift by
int box = listView1.Items.Count - 1; //size of box
int half = Convert.ToInt32(listView1.Items.Count / 2);
int corner = 0; //inside corner of box
if (shift > listView1.Items.Count)
{
shift = shift % ((listView1.Items.Count - 2) * 4);
}
do
{
eachPass(shift, box, corner);
++corner;
--box;
} while (box >= half + 1);
}
public void eachPass(int shift, int box, int corner)
{
int x;
int i;
//Read each non-diagonal value into one of two lists
for (x = corner + 1; x < box; x++)
{
topRight.AddLast(listView1.Items[corner].SubItems[x].Text);
}
x = box;
for (i = corner + 1; i < box; i++)
{
topRight.AddLast(listView1.Items[i].SubItems[x].Text);
}
for (x = box - 1; x > corner; x--)
{
bottomLeft.AddLast(listView1.Items[box].SubItems[x].Text);
}
x = corner;
for (i = box - 1; i > corner; i--)
{
bottomLeft.AddLast(listView1.Items[i].SubItems[x].Text);
}
string myTest = "";
//join the two lists, so they can be shifted
foreach (string tR in topRight)
{
myMatrix.AddLast(tR);
}
foreach (string bL in bottomLeft)
{
myMatrix.AddLast(bL);
}
int sh;
//shift the list using another list
for (sh = shift; sh < myMatrix.Count; sh++)
{
shiftMatrix.AddLast(myMatrix.ElementAt(sh));
}
for (sh = 0; sh < shift; sh++)
{
shiftMatrix.AddLast(myMatrix.ElementAt(sh));
}
//we need the sizes of the current lists
int trCnt = topRight.Count;
int blCnt = bottomLeft.Count;
//clear them for reuse
topRight.Clear();
bottomLeft.Clear();
int s;
//put the shifted values back
for (s = 0; s < trCnt; s++)
{
topRight.AddLast(shiftMatrix.ElementAt(s));
}
for (s = blCnt; s < shiftMatrix.Count; s++)
{
bottomLeft.AddLast(shiftMatrix.ElementAt(s));
}
int tRn = 0;
int bLn = 0;
//write each non-diagonal value from one of two lists
for (x = corner + 1; x < box; x++)
{
listView1.Items[corner].SubItems[x].Text = topRight.ElementAt(tRn);
++tRn;
}
x = box;
for (i = corner + 1; i < box; i++)
{
listView1.Items[i].SubItems[x].Text = topRight.ElementAt(tRn);
++tRn;
}
for (x = box - 1; x > corner; x--)
{
listView1.Items[box].SubItems[x].Text = bottomLeft.ElementAt(bLn);
++bLn;
}
x = corner;
for (i = box - 1; i > corner; i--)
{
listView1.Items[i].SubItems[x].Text = bottomLeft.ElementAt(bLn);
++bLn;
}
myMatrix.Clear();
shiftMatrix.Clear();
topRight.Clear();
bottomLeft.Clear();
}
}
}

C# array into MWarray Matlab

I have an MxNx3 matrix and i want to transfer it into matlab using MWArray.
Here is my code, however there is no CTOR for that.
Is there any way to do it?
RGBImage image = _currentImage as RGBImage;
int height = image.Height;
int width = image.Width;
//transform the 1D array of byte into MxNx3 matrix
byte[, ,] rgbByteImage = new byte[3, height, width];
if (image[0].Bpp > 16)
{
for (int i = 0; i < height; i++)
{
for (int j = 0, k = 0; k < width; j = j + 3, k++)
{
rgbByteImage[0, i, k] = image[0].Data[i * width + j];
rgbByteImage[1, i, k] = image[0].Data[i * width + j + 1];
rgbByteImage[2, i, k] = image[0].Data[i * width + j + 2 ];
}
}
}
MWNumericArray tempArr = new MWNumericArray(rgbByteImage);

RGBImage image = _currentImage as RGBImage;
int height = image.Height;
int width = image.Width;
//transform the 1D array of byte into MxNx3 matrix
byte[ , , ] RGBByteImage = new byte[3,height, width];
if (image[0].Bpp > 16)
{
for (int i = 0; i < height; i++)
{
for (int j = 0, k = 0; k < width; j = j + 3, k++)
{
RGBByteImage[0, i, k] = image[0].Data[3 * i * width + j];
RGBByteImage[1, i, k] = image[0].Data[3 * i * width + j + 1];
RGBByteImage[2, i, k] = image[0].Data[3 * i * width + j + 2];
}
}
}
MWNumericArray matrix = null;
matrix = new MWNumericArray(MWArrayComplexity.Real, MWNumericType.Int8, 3,height, width);
matrix = RGBByteImage;
This is what I have found.
There is also a nice tutorial here
http://domoreinlesstime.wordpress.com/2013/01/26/access-matlab-from-c/
Please notice that you have the correct refernce to the MWArray.dll file (x64 or x86). I have wasted a day or so on that.