void RawImageDataFloat::calculateBlackAreas() {
float accPixels[4] = {0,0,0,0};
int totalpixels = 0;
for (uint32 i = 0; i < blackAreas.size(); i++) {
BlackArea area = blackAreas[i];
/* Make sure area sizes are multiple of two,
so we have the same amount of pixels for each CFA group */
area.size = area.size - (area.size&1);
/* Process horizontal area */
if (!area.isVertical) {
if ((int)area.offset+(int)area.size > uncropped_dim.y)
ThrowRDE("RawImageData::calculateBlackAreas: Offset + size is larger than height of image");
for (uint32 y = area.offset; y < area.offset+area.size; y++) {
float *pixel = (float*)getDataUncropped(mOffset.x, y);
for (int x = mOffset.x; x < dim.x+mOffset.x; x++) {
accPixels[((y&1)<<1)|(x&1)] += *pixel++;
}
}
totalpixels += area.size * dim.x;
}
/* Process vertical area */
if (area.isVertical) {
if ((int)area.offset+(int)area.size > uncropped_dim.x)
ThrowRDE("RawImageData::calculateBlackAreas: Offset + size is larger than width of image");
for (int y = mOffset.y; y < dim.y+mOffset.y; y++) {
float *pixel = (float*)getDataUncropped(area.offset, y);
for (uint32 x = area.offset; x < area.size+area.offset; x++) {
accPixels[((y&1)<<1)|(x&1)] += *pixel++;
}
}
totalpixels += area.size * dim.y;
}
}
if (!totalpixels) {
for (int i = 0 ; i < 4; i++)
blackLevelSeparate[i] = blackLevel;
return;
}
/* Calculate median value of black areas for each component */
/* Adjust the number of total pixels so it is the same as the median of each histogram */
totalpixels /= 4;
for (int i = 0 ; i < 4; i++) {
blackLevelSeparate[i] = (int)(65535.0f * accPixels[i]/totalpixels);
}
/* If this is not a CFA image, we do not use separate blacklevels, use average */
if (!isCFA) {
int total = 0;
for (int i = 0 ; i < 4; i++)
total+=blackLevelSeparate[i];
for (int i = 0 ; i < 4; i++)
blackLevelSeparate[i] = (total+2)>>2;
}
void RawImageDataU16::calculateBlackAreas() {
int* histogram = (int*)malloc(4*65536*sizeof(int));
memset(histogram, 0, 4*65536*sizeof(int));
int totalpixels = 0;
for (uint32 i = 0; i < blackAreas.size(); i++) {
BlackArea area = blackAreas[i];
/* Make sure area sizes are multiple of two,
so we have the same amount of pixels for each CFA group */
area.size = area.size - (area.size&1);
/* If offset is negative (relative to right or bottom border) calculate
the offset from the left or top border */
if(area.offset < 0)
area.offset += area.isVertical ? uncropped_dim.x : uncropped_dim.y;
/* Process horizontal area */
if (!area.isVertical) {
if ((int)area.offset+(int)area.size > uncropped_dim.y)
ThrowRDE("RawImageData::calculateBlackAreas: Offset + size is larger than height of image");
for (uint32 y = area.offset; y < area.offset+area.size; y++) {
ushort16 *pixel = (ushort16*)getDataUncropped(mOffset.x, y);
int* localhist = &histogram[(y&1)*(65536*2)];
for (int x = mOffset.x; x < dim.x+mOffset.x; x++) {
localhist[((x&1)<<16) + *pixel]++;
}
}
totalpixels += area.size * dim.x;
}
/* Process vertical area */
if (area.isVertical) {
if ((int)area.offset+(int)area.size > uncropped_dim.x)
ThrowRDE("RawImageData::calculateBlackAreas: Offset + size is larger than width of image");
for (int y = mOffset.y; y < dim.y+mOffset.y; y++) {
ushort16 *pixel = (ushort16*)getDataUncropped(area.offset, y);
int* localhist = &histogram[(y&1)*(65536*2)];
for (uint32 x = area.offset; x < area.size+area.offset; x++) {
localhist[((x&1)<<16) + *pixel]++;
}
}
totalpixels += area.size * dim.y;
}
}
if (!totalpixels) {
for (int i = 0 ; i < 4; i++)
blackLevelSeparate[i] = blackLevel;
free(histogram);
return;
}
/* Calculate median value of black areas for each component */
/* Adjust the number of total pixels so it is the same as the median of each histogram */
totalpixels /= 4*2;
for (int i = 0 ; i < 4; i++) {
int* localhist = &histogram[i*65536];
int acc_pixels = localhist[0];
int pixel_value = 0;
while (acc_pixels <= totalpixels && pixel_value < 65535) {
pixel_value++;
acc_pixels += localhist[pixel_value];
}
blackLevelSeparate[i] = pixel_value;
}
/* If this is not a CFA image, we do not use separate blacklevels, use average */
if (!isCFA) {
int total = 0;
for (int i = 0 ; i < 4; i++)
total+=blackLevelSeparate[i];
for (int i = 0 ; i < 4; i++)
blackLevelSeparate[i] = (total+2)>>2;
}