public static string PixelValues(DigitImage dImage)
{
// create a string, with embedded newlines, suitable
// for display in a multi-line TextBox control
string s = "";
for (int i = 0; i < dImage.height; ++i)
{
for (int j = 0; j < dImage.width; ++j)
{
s += dImage.pixels[i][j].ToString("X2") + " ";
}
s += Environment.NewLine;
}
return(s);
}
private void button2_Click(object sender, EventArgs e) // Display 'next' image
{
int nextIndex = int.Parse(textBox4.Text);
DigitImage currImage = trainImages[nextIndex];
int mag = int.Parse(comboBox1.SelectedItem.ToString()); // magnification
Bitmap bitMap = MakeBitmap(currImage, mag);
pictureBox1.Image = bitMap;
string pixelVals = PixelValues(currImage);
textBox5.Text = pixelVals;
textBox3.Text = textBox4.Text; // update curr idx from old next idz
textBox4.Text = (nextIndex + 1).ToString(); // ++next index
listBox1.Items.Add("Curr image index = " + textBox3.Text + " label = " + currImage.label);
}
} // LoadData
public static Bitmap MakeBitmap(DigitImage dImage, int mag)
{
// create a C# Bitmap suitable for display in a PictureBox control
int width = dImage.width * mag;
int height = dImage.height * mag;
Bitmap result = new Bitmap(width, height);
Graphics gr = Graphics.FromImage(result);
for (int i = 0; i < dImage.height; ++i)
{
for (int j = 0; j < dImage.width; ++j)
{
int pixelColor = 255 - dImage.pixels[i][j]; // white background, black digits
//int pixelColor = dImage.pixels[i][j]; // black background, white digits
Color c = Color.FromArgb(pixelColor, pixelColor, pixelColor); // gray scale
//Color c = Color.FromArgb(pixelColor, 0, 0); // red scale
SolidBrush sb = new SolidBrush(c);
gr.FillRectangle(sb, j * mag, i * mag, mag, mag); // fills bitmap via Graphics object
}
}
return(result);
}
public static DigitImage[] LoadData(string pixelFile, string labelFile)
{
// Load MNIST training set of 60,000 images into memory
// remove static to access listBox1
int numImages = 60000;
DigitImage[] result = new DigitImage[numImages];
byte[][] pixels = new byte[28][];
for (int i = 0; i < pixels.Length; ++i)
{
pixels[i] = new byte[28];
}
FileStream ifsPixels = new FileStream(pixelFile, FileMode.Open);
FileStream ifsLabels = new FileStream(labelFile, FileMode.Open);
BinaryReader brImages = new BinaryReader(ifsPixels);
BinaryReader brLabels = new BinaryReader(ifsLabels);
int magic1 = brImages.ReadInt32(); // stored as Big Endian
magic1 = ReverseBytes(magic1); // convert to Intel format
int imageCount = brImages.ReadInt32();
imageCount = ReverseBytes(imageCount);
int numRows = brImages.ReadInt32();
numRows = ReverseBytes(numRows);
int numCols = brImages.ReadInt32();
numCols = ReverseBytes(numCols);
int magic2 = brLabels.ReadInt32();
magic2 = ReverseBytes(magic2);
int numLabels = brLabels.ReadInt32();
numLabels = ReverseBytes(numLabels);
// each image
for (int di = 0; di < numImages; ++di)
{
for (int i = 0; i < 28; ++i) // get 28x28 pixel values
{
for (int j = 0; j < 28; ++j)
{
byte b = brImages.ReadByte();
pixels[i][j] = b;
}
}
byte lbl = brLabels.ReadByte(); // get the label
DigitImage dImage = new DigitImage(28, 28, pixels, lbl);
result[di] = dImage;
} // each image
ifsPixels.Close(); brImages.Close();
ifsLabels.Close(); brLabels.Close();
return(result);
} // LoadData