  We propose a new post-processing technique for the detection of faint
companions from a sequence of adaptive optics corrected short exposures. The
algorithm exploits the difference in shape between the on-axis and off-axis
irradiance distributions and it does not require the signal to be above the
noise level. We show that the method is particularly useful in dealing with
static speckles. Its application to real and simulated data gives excellent
results in the low-signal regime where it outperforms the standard approach of
computing signal-to-noise ratio on one long exposure. We also show that
accurate noise estimation in adaptive optics images of close companions is
rendered impossible due to the presence of static speckles. This new method
provides means of reliable estimation of the confidence intervals for the
detection hypothesis.
