/** {@inheritDoc} */
@Override
public K compute(K src, K res) {
/*
* ImgMap<UnsignedByteType, T> map = new
* ImgMap<UnsignedByteType, T>( new Convert<UnsignedByteType,
* T>(res.firstElement() .createVariable(),
* src.firstElement()));
*
* res = map.compute(src);
*/
// res = srcIn;
RandomAccess<T> resAccess = res.randomAccess();
RandomAccess<T> srcAccess = src.randomAccess();
int n = (int) src.dimension(0);
int m = (int) src.dimension(1);
int minx = 0;
int maxx = (int) src.dimension(0);
int miny = 0;
int maxy = (int) src.dimension(1);
// int maxx = Integer.MIN_VALUE;
// int minx = Integer.MAX_VALUE;
// int maxy = Integer.MIN_VALUE;
// int miny = Integer.MAX_VALUE;
int xrange = n;
int yrange = m;
int pixelrange = (int) (srcAccess.get().getMaxValue() - srcAccess.get().getMinValue());
// TODO: Binning of histogram
// initialise column histograms and blockhistogram
QuantileHistogram blockhistogram = new QuantileHistogram(pixelrange);
@SuppressWarnings("unchecked")
QuantileHistogram[] columnhistograms = new QuantileFilter.QuantileHistogram[xrange];
for (int i = 0; i < xrange; i++) {
columnhistograms[i] = new QuantileHistogram(pixelrange);
}
int act_x_radius = 0, act_y_radius = 0;
int x, y;
int pixel;
int actx, acty;
// iterate through all rows
for (int i = 0; i < yrange; i++) {
y = miny + i;
// compute the actual radius in y direction (respect the
// boundary!)
if (y - m_radius >= miny) {
if (y + m_radius <= maxy) {
act_y_radius = m_radius;
} else {
act_y_radius = Math.max(0, maxy - y);
}
} else {
if (2 * y <= maxy) {
act_y_radius = y;
} else {
act_y_radius = Math.max(0, maxy - y);
}
}
// clear the current blockhistogram (must be
// reconstructed at the
// boundaries anyway)
blockhistogram.clear();
// iterate through all columns
for (int j = 0; j < xrange; j++) {
x = minx + j;
// compute the actual radius in x direction
// (respect the
// boundary!)
if (x - m_radius >= minx) {
if (x + m_radius <= maxx) {
act_x_radius = m_radius;
} else {
act_x_radius = Math.max(0, maxx - x);
}
} else {
if (2 * x <= maxx) {
act_x_radius = x;
} else {
act_x_radius = Math.max(0, maxx - x);
}
}
srcAccess.setPosition(x, 0);
// cursor.setPosition(x, dimx);
// set the column histogram
if (i <= m_radius) {
// special treatment for the first
// radius rows
acty = y + act_y_radius;
// cursor.setPosition(acty, dimy);
srcAccess.setPosition(acty, 1);
pixel = (int) (srcAccess.get().getRealDouble() - srcAccess.get().getMinValue());
columnhistograms[j].addPixel(pixel);
acty--;
if (acty > 0) {
srcAccess.setPosition(acty, 1);
// cursor.setPosition(acty,
// dimy);
pixel = (int) (srcAccess.get().getRealDouble() - srcAccess.get().getMinValue());
columnhistograms[j].addPixel(pixel);
}
} else {
if (i >= yrange - m_radius) {
// special treatment for the
// last radius rows
acty = y - act_y_radius - 1;
if (acty >= 0) {
srcAccess.setPosition(acty, 1);
// cursor.setPosition(acty,
// dimy);
pixel = (int) (srcAccess.get().getRealDouble() - srcAccess.get().getMinValue());
columnhistograms[j].subPixel(pixel);
acty--;
if (acty >= 0) {
// cursor.setPosition(acty,
// dimy);
srcAccess.setPosition(acty, 1);
pixel = (int) (srcAccess.get().getRealDouble() - srcAccess.get().getMinValue());
columnhistograms[j].subPixel(pixel);
}
}
} else {
if (y - m_radius - 1 >= miny && y - m_radius - 1 <= maxy) {
// cursor.setPosition(y
// - m_radius - 1,
// dimy);
srcAccess.setPosition(y - m_radius - 1, 1);
pixel = (int) (srcAccess.get().getRealDouble() - srcAccess.get().getMinValue());
columnhistograms[j].subPixel(pixel);
}
if (y + m_radius >= miny && y + m_radius <= maxy) {
// cursor.setPosition(y
// + m_radius, dimy);
srcAccess.setPosition(y + m_radius, 1);
pixel = (int) (srcAccess.get().getRealDouble() - srcAccess.get().getMinValue());
columnhistograms[j].addPixel(pixel);
}
}
}
}
// iterate through all columns again
for (int j = 0; j < xrange; j++) {
x = minx + j;
// compute the actual radius in x direction
// (respect the
// boundary!)
if (x - m_radius >= minx) {
if (x + m_radius <= maxx) {
act_x_radius = m_radius;
} else {
act_x_radius = Math.max(0, maxx - x);
}
} else {
if (2 * x <= maxx) {
act_x_radius = x;
} else {
act_x_radius = Math.max(0, maxx - x);
}
}
// set the block histogram
if (j <= m_radius) {
// special treatment for the first
// radius columns
actx = x + act_x_radius;
if (actx >= minx && actx <= maxx) {
blockhistogram.add(columnhistograms[actx - minx]);
actx--;
if (actx >= minx && actx <= maxx) {
blockhistogram.add(columnhistograms[actx - minx]);
}
}
} else {
if (j >= xrange - m_radius) {
// special treatment for the
// last radius columns
actx = x - act_x_radius - 1;
if (actx >= minx && actx <= maxx) {
blockhistogram.sub(columnhistograms[actx - minx]);
actx--;
if (actx >= minx && actx <= maxx) {
blockhistogram.sub(columnhistograms[actx - minx]);
}
}
} else {
if (x - m_radius - 1 >= minx && x - m_radius - 1 <= maxx) {
blockhistogram.sub(columnhistograms[x - minx - m_radius - 1]);
}
if (x + m_radius >= minx && x + m_radius <= maxx) {
blockhistogram.add(columnhistograms[x - minx + m_radius]);
}
}
}
resAccess.setPosition(x, 0);
resAccess.setPosition(y, 1);
resAccess.get().setReal(blockhistogram.getQuantile(m_quantile));
}
}
return res;
}
