evalROC.m

%% A demo code to compute ROC curve for evaluating salient object detection algorithms
% Yao Li, Jan 2014
% please cite our paper "Contextual Hypergraph Modeling for Salient Object
% Detection", ICCV 2013, if you use the code in your research
%% initialization
clear all
close all;clc;
method = 'hypergraph'; % name of the salient object method you want to evaluate, you need to change this
dataset = 'MSRA1000'; % name of dataset, you need to change this
resultpath = ['../../Result/',dataset,'/',method,'/*.png']; % path to saliency maps, you need to change this
truthpath = ['../../Dataset/',dataset,'_binarymasks/*.bmp']; % path to ground-truth masks, yoiu need to change this
savepath = './result/ROC/';
if ~exist(savepath,'dir')
    mkdir(savepath);
end
dir_im = dir(resultpath);
assert(~isempty(dir_im),'No saliency map found, please check the path!');
dir_tr= dir(truthpath);
assert(~isempty(dir_tr),'No ground-truth image found, please check the path!');
assert(length(dir_im)==length(dir_tr),'The number of saliency maps and ground-truth images are not equal!')
imNum = length(dir_tr);
TPR = zeros(256,1);
FPR = zeros(256,1);
%% compute ROC
for i = 1:imNum
  imName = dir_tr(i).name;
  input_im = imread([resultpath(1:end-5),imName(1:end-4),resultpath(end-3:end)]);
  truth_im = imread([truthpath(1:end-5),imName]);
  truth_im = truth_im(:,:,1);
  input_im = input_im(:,:,1);
     if max(max(truth_im))==255
        truth_im = truth_im./255;
     end
    P = sum(sum(truth_im));
    N = sum(sum(~truth_im));
    for threshold = 0:255
        if P~=0 && N~=0
        index1 = (input_im>=threshold);
        TP = sum(sum(truth_im & index1));
        FP = sum(sum((~truth_im) & index1));
        TPR(threshold+1) = TPR(threshold+1)+TP/P;
        FPR(threshold+1) = FPR(threshold+1)+FP/N; 
        end
    end
    display(num2str(i));
end    
TPR = TPR/imNum;
FPR = FPR/imNum;
index = (TPR>1);
TPR(index)=1;
index = (FPR>1);
FPR(index)=1;
ROC = [TPR';FPR'];
fid = fopen([savepath dataset '_' method '_ROCcurve.txt'],'at');
fprintf(fid,'%f %f\n',ROC);
fclose(fid);
disp('Done!');