To compile the onset evaluator in Linux or MacOS, type from the command
line:

g++ -o eval evaluator_onsets.cpp 

The execution syntax is:

./eval <ground-truth.txt> <detected_onsets.txt>

Where ground-truth.txt contains the ground-truth onset times, and
detected_onsets.txt, the detected times. In the text files, each time (in
seconds) must be in a row. Ex:

0.012
0.235552
1.24232
....

The results of the evaluation are printed in stdout.