public static CharBitmapProperty characterExtraction(ref Bitmap input, Range xrange, Range yrange)
{
int x0 = xrange.Item1;
int x1 = xrange.Item2;
int y0 = yrange.Item1;
int y1 = yrange.Item2;
// TODO: 'b', 'd' , 'f' are taller than normal number char
// If number digits are at the same line as 'b', 'd', 'f',
// their bitmap would have one more line of bits.
// Try to ignore this line by post processing the y0 line.
while (true)
{
bool all0 = true;
for (int i = x0; i < x1; i++)
{
if (rgb2gray(input.GetPixel(i, y0)) != 0)
{
all0 = false;
break;
}
}
if (all0)
{
y0 = y0 + 1;
}
else {
break;
}
}
int xm = (x1 + x0) / 2;
int ym = (y1 + y0) / 2;
//
// 00 01
// 10 11
//
int score00 = 0;
int score01 = 0;
int score10 = 0;
int score11 = 0;
for (int x = x0; x < xm; x++)
{
for (int y = y0; y < ym; y++)
{
score00 += rgb2gray(input.GetPixel(x, y));
}
}
for (int x = xm; x < x1; x++)
{
for (int y = y0; y < ym; y++)
{
score01 += rgb2gray(input.GetPixel(x, y));
}
}
for (int x = x0; x < xm; x++)
{
for (int y = ym; y < y1; y++)
{
score10 += rgb2gray(input.GetPixel(x, y));
}
}
for (int x = xm; x < x1; x++)
{
for (int y = ym; y < y1; y++)
{
score11 += rgb2gray(input.GetPixel(x, y));
}
}
score00 = score00 / ((xm - x0) * (ym - y0));
score01 = score01 / ((x1 - xm) * (ym - y0));
score10 = score10 / ((xm - x0) * (y1 - ym));
score11 = score11 / ((x1 - xm) * (y1 - ym));
// debug
// dumpBitmap(ref input, xrange, yrange);
int total = score00 + score01 + score10 + score11;
int[] tempA = { total, score00, score01, score10, score11 };
CharBitmapProperty t = new CharBitmapProperty(tempA);
// Console.WriteLine(t.ToString());
return t;
}
// TODO:
public char charRecognition(CharBitmapProperty t)
{
char result = '?';
int best_score = int.MaxValue;
for (int i = 0; i < myDB.Count; i++)
{
CharBitmapProperty tmp = t - myDB[i].Item1;
int theScore = tmp.magnitude();
if (theScore < best_score)
{
result = myDB[i].Item2;
best_score = theScore;
}
}
return result;
}