1. Method for real time visualisation and demarcation of tumours by means of photodynamic method and analysis of the fluorescent multispectral image comprising following steps: recording of the fluorescent image ( 1 ) by multispectral camera ( 6 ) where fluorescent image ( 1 ) is represented by the linear combination of the unknown classes S, transformation of fluorescent multispectral image into new multispectral image ( 2 ) by using nonlinear dimensionality expansion, linear transformation of the multispectral image ( 2 ) with extended dimensionality, independent component analysis of the innovation representation of the multispectral image ( 3 ) that is result of the transformations of the fluorescent multispectral image ( 1 ) and multispectral image ( 2 ), extraction of the tumour map or class of interest according to the chosen criterion, and visualisation of the tumour.