CONSIDERATIONS REGARDING THE USE OF THE BIOLOGICALLY INSPIRED RETINEX ALGORITHM IN ART CONSERVATION–RESTORATION

This paper addresses the problem of separating the illumination from the reflectance in images and compensating for non-uniform lighting. Recorded images of mural paintings suffer from significant losses in visual quality, compared to the direct eye observation when there are spatial or spectral variations in illumination. The visibility of detail in shadows is poor for recorded images and therefore an automatic computation is needed to improve them for better optical investigation. Images of medieval mural paintings, taken under very poor illumination conditions, are processed by the biologically inspired Retinex algorithm and by the equalize algorithm and the results are compared.