  Large spectroscopic surveys such as the Gaia-ESO Survey produce huge
quantities of data. Automatic tools are necessary to efficiently handle this
material. The measurement of equivalent widths in stellar spectra is
traditionally done by hand or with semi-automatic procedures that are
time-consuming and not very robust with respect to the repeatability of the
results. The program DAOSPEC is a tool that provides consistent measurements of
equivalent widths in stellar spectra while requiring a minimum of user
intervention. However, it is not optimised to deal with large batches of
spectra, as some parameters still need to be modified and checked by the user.
Exploiting the versatility and portability of BASH, we have built a pipeline
called DAOSPEC Option Optimiser (DOOp) automating the procedure of equivalent
widths measurement with DAOSPEC. DOOp is organised in different modules that
run one after the other to perform specific tasks, taking care of the
optimisation of the parameters needed to provide the final equivalent widths,
and providing log files to ensure better control over the procedure. In this
paper, making use of synthetic and observed spectra, we compare the performance
of DOOp with other methods, including DAOSPEC used manually. The measurements
made by DOOp are identical to the ones produced by DAOSPEC when used manually,
while requiring less user intervention, which is convenient when dealing with a
large quantity of spectra. DOOp shows its best performance on high-resolution
spectra (R>20 000) and high signal-to-noise ratio (S/N>30), with uncertainties
ranging from 6 m{\AA} to 2 m{\AA}. The only subjective parameter that remains
is the normalisation, as the user still has to make a choice on the order of
the polynomial used for the continuum fitting. As a test, we use the equivalent
widths measured by DOOp to re-derive the stellar parameters of four
well-studied stars.
