Cody

# Problem 42616. Detect circles in images

Solution 773100

Submitted on 7 Nov 2015 by Alfonso Nieto-Castanon
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### Test Suite

Test Status Code Input and Output
1   Pass
%% I = imread(fullfile(matlabroot,'toolbox','images','imdata','circles.png')); [centers,radii] = detectcircles(I,[18 20],13); c = [119 222; 185 218; 124 116; 37 37; 178 184; 93 167; 37 72; 71 38; 93 132; 122 186; 97 96; 71 74; 151 204]; r = 19*ones(13,1); d1 = squeeze(sqrt(sum(bsxfun(@minus,centers,permute(c,str2num('3 2 1'))).^2,2))); d2 = squeeze(sqrt(sum(bsxfun(@minus,radii,permute(r,str2num('3 2 1'))).^2,2))); mask = d1<5 & d2<5; Re = mean(any(mask)); Pr = sum(any(mask))/size(mask,1); assert(Pr>=0.5) assert(Re>=0.75)

118 184 70 35 35 91 176 123 92 70 120 95 149 221 217 36 71 35 166 183 115 130 72 184 95 203 19 18 19 19 18 19 19 18 19 19 18 19 18

2   Pass
%% I = imread(fullfile(matlabroot,'toolbox','images','imdata','circlesBrightDark.png')); [centers,radii] = detectcircles(I,[32 64],6); c = [75 250; 100 100; 250 400; 300 120; 450 240; 330 370]; r = [35; 50; 60; 40; 50; 55]; d1 = squeeze(sqrt(sum(bsxfun(@minus,centers,permute(c,str2num('3 2 1'))).^2,2))); d2 = squeeze(sqrt(sum(bsxfun(@minus,radii,permute(r,str2num('3 2 1'))).^2,2))); mask = d1<5 & d2<5; Re = mean(any(mask)); Pr = sum(any(mask))/size(mask,1); assert(Pr>=0.5) assert(Re>=0.75)

298 73 448 328 98 248 118 248 238 368 98 398 40 35 51 55 51 61

3   Pass
%% I = imread(fullfile(matlabroot,'toolbox','images','imdata','coins.png')); [centers,radii] = detectcircles(I,[24 30],10); c = [236 174; 149 35; 56 50; 266 103; 217 71; 120 209; 110 85; 175 120; 96 146; 37 107]; r = [25; 29; 25; 24; 29; 29; 24; 29; 29; 29]; d1 = squeeze(sqrt(sum(bsxfun(@minus,centers,permute(c,str2num('3 2 1'))).^2,2))); d2 = squeeze(sqrt(sum(bsxfun(@minus,radii,permute(r,str2num('3 2 1'))).^2,2))); mask = d1<5 & d2<5; Re = mean(any(mask)); Pr = sum(any(mask))/size(mask,1); assert(Pr>=0.5) assert(Re>=0.75)

147 118 215 173 94 264 54 234 35 108 34 207 70 119 145 101 48 171 106 83 30 30 30 30 30 25 25 25 30 25

4   Pass
%% I = imread(fullfile(matlabroot,'toolbox','images','imdata','coloredChips.png')); [centers,radii] = detectcircles(I,[20 28],26); c = [83 177; 304 336; 420 88; 434 165; 244 166; 327 297; 273 53; 130 44; 271 281; 408 265; 312 192; 420 346; 146 199; 228 232; 329 135; 175 297; 366 224; 150 258; 217 107; 345 119; 445 68; 372 293; 150 342; 251 8; 259 217; 198 107]; r = [23; 24; 23; 23; 23; 23; 23; 23; 23; 23; 23; 24; 23; 23; 23; 24; 23; 24; 23; 23; 23; 24; 25; 23; 23; 25]; d1 = squeeze(sqrt(sum(bsxfun(@minus,centers,permute(c,str2num('3 2 1'))).^2,2))); d2 = squeeze(sqrt(sum(bsxfun(@minus,radii,permute(r,str2num('3 2 1'))).^2,2))); mask = d1<5 & d2<5; Re = mean(any(mask)); Pr = sum(any(mask))/size(mask,1); assert(Pr>=0.5) assert(Re>=0.75)

Columns 1 through 16 127 241 310 270 406 196 143 148 363 269 418 326 172 442 324 370 42 164 191 51 263 105 197 256 222 279 344 133 295 66 294 290 Columns 17 through 26 257 419 148 226 343 431 79 298 248 216 216 86 341 230 117 163 174 334 6 105 Columns 1 through 16 23 23 23 22 23 22 23 23 23 23 23 23 23 23 23 23 Columns 17 through 26 22 22 24 23 23 21 21 24 22 20

5   Pass
%% I = imread(fullfile(matlabroot,'toolbox','images','imdata','eight.tif')); [centers,radii] = detectcircles(I,[35 40],4); c = [198 189; 247 72; 62 141; 124 58]; r = [37; 37; 38; 37]; d1 = squeeze(sqrt(sum(bsxfun(@minus,centers,permute(c,str2num('3 2 1'))).^2,2))); d2 = squeeze(sqrt(sum(bsxfun(@minus,radii,permute(r,str2num('3 2 1'))).^2,2))); mask = d1<5 & d2<5; Re = mean(any(mask)); Pr = sum(any(mask))/size(mask,1); assert(Pr>=0.5) assert(Re>=0.75)

59 196 245 121 139 186 70 56 39 39 38 39

6   Pass

252 285 206

7   Pass
%% I = imread(fullfile(matlabroot,'toolbox','images','imdata','pillsetc.png')); [centers,radii] = detectcircles(I,[15 55],4); c = [103 240; 252 326; 119 130; 319 84]; r = [17; 17; 50; 37]; d1 = squeeze(sqrt(sum(bsxfun(@minus,centers,permute(c,str2num('3 2 1'))).^2,2))); d2 = squeeze(sqrt(sum(bsxfun(@minus,radii,permute(r,str2num('3 2 1'))).^2,2))); mask = d1<5 & d2<5; Re = mean(any(mask)); Pr = sum(any(mask))/size(mask,1); assert(Pr>=0.5) assert(Re>=0.75)

249 101 118 315 324 238 132 76 17 17 48 42

8   Pass

234 171 80

9   Pass

126 126 116

10   Pass

264 504 93

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