bool ZStackBinarizer::binarize(Stack *stack)
{
if (stack == NULL) {
return false;
}
int threshold = m_threshold;
int *hist = NULL;
Stack *refStack = C_Stack::clone(m_reference);
if (refStack == NULL) {
refStack = stack;
}
int low = m_lowerBound;
int high = m_upperBound;
switch (m_method) {
case BM_RC_THRESHOLD:
case BM_STABLE_POINT:
case BM_TRIANGLE:
hist = Stack_Hist(refStack);
break;
case BM_LOCMAX:
hist = computeLocmaxHist(refStack);
break;
default:
break;
}
if (hist != NULL) {
if (m_lowerBound < 0) {
low = Int_Histogram_Min(hist);
}
if (m_upperBound < 0) {
high = Int_Histogram_Max(hist);
}
}
if (low == high && hist != NULL) {
BINARIZE_CLEAN
return false;
}
int* Int_Histogram_Equalize(const int *hist, int min, int max)
{
/* <map> allocated */
int *map = iarray_malloc(Int_Histogram_Length(hist) + 2);
map[1] = Int_Histogram_Min(hist);
int i;
map[0] = Int_Histogram_Length(hist);
const int *hist_array = Int_Histogram_Const_Array(hist);
int cumsum = 0;
int sum = iarray_sum(hist_array, map[0]);
for (i = 0; i < map[0]; i++) {
cumsum += hist_array[i];
map[i + 2] = min +
(max - min) * (cumsum - hist_array[0]) / (sum - hist_array[0]);
}
/* <map> returned */
return map;
}
int ZIntHistogram::getMinValue() const
{
return Int_Histogram_Min(m_hist);
}
int* Int_Histogram_Equal_Info_Map(const int *hist, int nbin, int *map)
{
int length = Int_Histogram_Length(hist);
int min = Int_Histogram_Min(hist);
if (map == NULL) {
map = iarray_malloc(length);
}
const int *hist_array = Int_Histogram_Const_Array(hist);
/* alloc <info> */
double *info = darray_malloc(length);
int i;
for (i = 0; i < length; i++) {
if (hist_array[i] == 0) {
info[i] = 0;
} else {
if (min +i == 0) {
info[i] = log(hist_array[i]);
} else
info[i] = log(hist_array[i]) + log(min + i);
}
}
double total_number = darray_sum(info, length);
int current_index = 0;
double threshold = total_number / nbin;
double count = info[0];
map[0] = current_index;
for (i = 1; i < length; i++) {
if (nbin - map[i-1] - 1 >= length - i) {
int j;
current_index = map[i-1] + 1;
for (j = i; j < length; j++) {
map[j] = current_index++;
}
break;
}
count += info[i];
if (count <= threshold) {
map[i] = current_index;
} else {
total_number -= count;
if (count - threshold >= threshold + info[i] - count) {
total_number += info[i];
count = info[i];
map[i] = current_index + 1;
} else {
count = 0;
map[i] = current_index;
}
current_index++;
/* this case should not happen */
if (current_index > 255) {
current_index = 255;
}
/* update threshold */
threshold = total_number / (nbin - current_index);
}
}
/* free <info> */
free(info);
return map;
}
