An image captured by a CCD camera at the output of an optical fibre has been divided into many small regions. In each region we find the first N moments and then calculate another distribution that has the same first N moments but also the maximum entropy. Noise reduction is thus associated with the elimination of the detailed information in the higher moments of the observed distribution. Results for various sizes of the regions and various values of the number of moments N will be presented.
A second approach has also been considered where many images have been captured at different times providing a distribution of the intensity at each pixel. We calculate the average \mu_i and standard deviation \sigma_i of the intensity at the pixel i and maximise the entropy with the constraint that
is smaller than a certain value. Several examples will be presented.
The work applies the powerful maximum entropy technique in the context of noise reduction in optical fibre systems and could play an important role in increasing the sensitivity of these systems.