bwCentroid - get centroid of dark or light pixels in BWImage [1005817]

< > BotCompany Repo | #1005817 // bwCentroid - get centroid of dark or light pixels in BWImage

JavaX fragment (include)

// returns pair of x and y
static Pair<Float, Float> bwCentroid(BWImage img, bool dark) {
  int w = img.getWidth(), h = img.getHeight();
  double sumX = 0, sumY = 0;
  double midX = (w-1)/2.0, midY = (h-1)/2.0; // optimized for odd image dimensions
  for y to h: for x to w: {
    float weight = img.getPixel(x, y);
    if (dark) weight = 1-weight;
    sumX += weight*(x-midX);
    sumY += weight*(y-midY);
  }
  double baseX = midX*h, baseY = midY*w;
  ret new Pair((float) (midX+sumX/baseX), (float) (midY+sumY/baseY));
}

Author comment

Began life as a copy of #1005814

Travelled to 14 computer(s): aoiabmzegqzx, bhatertpkbcr, cbybwowwnfue, cfunsshuasjs, gwrvuhgaqvyk, ishqpsrjomds, lpdgvwnxivlt, mqqgnosmbjvj, pyentgdyhuwx, pzhvpgtvlbxg, sawdedvomwva, tslmcundralx, tvejysmllsmz, vouqrxazstgt

Snippet ID:

#1005817

Snippet name:

bwCentroid - get centroid of dark or light pixels in BWImage

Eternal ID of this version:

#1005817/1

Text MD5:

2946ffee8aec0b1fb56a230021188c47

Author:

stefan

Category:

javax / imaging

Type:

JavaX fragment (include)

Public (visible to everyone):

Yes

Archived (hidden from active list):

Created/modified:

2016-12-10 15:46:45

Source code size:

536 bytes / 14 lines

Pitched / IR pitched:

No / No

Views / Downloads:

513 / 571

Referenced in:

[show references]

1	// returns pair of x and y
2	static Pair<Float, Float> bwCentroid(BWImage img, bool dark) {
3	int w = img.getWidth(), h = img.getHeight();
4	double sumX = 0, sumY = 0;
5	double midX = (w-1)/2.0, midY = (h-1)/2.0; // optimized for odd image dimensions
6	for y to h: for x to w: {
7	float weight = img.getPixel(x, y);
8	if (dark) weight = 1-weight;
9	sumX += weight*(x-midX);
10	sumY += weight*(y-midY);
11	}
12	double baseX = midXh, baseY = midYw;
13	ret new Pair((float) (midX+sumX/baseX), (float) (midY+sumY/baseY));
14	}