public fData Next()
{
// 0. assert images
if (images.Count == 0)
{
return(null);
}
// 1. get next fData
int i = Math.Daemon.Random.Next(0, idx.Count);
fData f = images[idx[i]];
idx.RemoveAt(i);
return(f);
}
public static IList <fData> ReadColorImage(string ubyteImageFileName, int?number,
double dataMin, double dataMax, double labelMin, double labelMax)
{
const int imageSize = 32;
const int imageLength = imageSize * imageSize * 3;
byte[] pixels;
IList <fData> images = new List <fData>();
fData image;
FileStream fileStreamImage;
BinaryReader imageReader;
byte[] byteImage;
Random random = new Random();
try
{
//Stream byte data from file
fileStreamImage = new FileStream(ubyteImageFileName, FileMode.Open, FileAccess.Read, FileShare.Read); // train images
imageReader = new BinaryReader(fileStreamImage);
byteImage = new byte[fileStreamImage.Length];
for (int i = 0; i < byteImage.Length; i++)
{
byteImage[i] = imageReader.ReadByte();
}
}
catch (Exception ex)
{
throw new Exception(ex.Message);
}
int nofStreamImages = byteImage.Length / (imageLength + 1);
bool[] retr = new bool[nofStreamImages];
long[] cntr = new long[10];
int j, n = 0, r;
byte l;
switch (number == null)
{
case false:
int nofImages = number.Value * 10;
while (n < nofImages)
{
r = random.Next(0, nofStreamImages);
j = r * (imageLength + 1);
pixels = new byte[imageLength];
l = byteImage[j];
if ((retr[r] == true) || (cntr[l] >= number))
{
continue;
}
for (int i = 1; i < imageLength; i++)
{
pixels[i] = byteImage[j + i];
}
// create image
image = new fData(pixels, dataMin, dataMax, EncodeLabel(l), labelMin, labelMax);
// add to list of images
images.Add(image);
// update records
retr[r] = true;
cntr[l] += 1;
++n;
}
break;
case true:
while (n < nofStreamImages)
{
j = n * (imageLength + 1);
pixels = new byte[imageLength];
l = byteImage[j];
for (int i = 1; i < imageLength; i++)
{
pixels[i] = byteImage[j + i];
}
// create image
image = new fData(pixels, dataMin, dataMax, EncodeLabel(l), labelMin, labelMax);
// add to list of images
images.Add(image);
++n;
}
break;
}
fileStreamImage.Close();
imageReader.Close();
return(images);
}
