Watershed image segmentation with optimized processing of image data by iterative reconstruction

A method (P400) for watershed segmentation of an image, implemented by a computing unit executing instructions stored in a non-transitory computer readable memory, which comprises:

• obtaining (S410) an image, each pixel of the image being associated with:
• a label indicating whether the pixel is a source pixel, the sources comprising local pixel intensity extrema of a first type;
• an indicator of a source associated with the pixel;
• an intensity of the pixel;
• a pixel intensity extremum of a second type on a path between the source associated with the pixel and the pixel, the second type of pixel intensity extremum being the inverse of the first type of pixel intensity extremum;
• at least one iteration (S430) of a traversal of successive pixels of the image until a stop criterion is satisfied (S440), said traversal comprising, for each current pixel to be processed in the traversal:
• if the pixel is not a source pixel and if, among the current pixel and the neighboring pixels belonging to a neighborhood of said current pixel, the extremum of the first type among the pixel intensity extrema of the second type on the paths between the sources associated with the pixels and the pixels, belongs to a neighboring pixel of said current pixel, or
• if the pixel is a source pixel and if, among the current pixel and the neighboring pixels belonging to a neighborhood of said current pixel and assigned to the same source, the extremum of the first type among the pixel intensity extrema of the second type on the paths between the sources associated with the pixels and the pixels, belongs to a neighboring pixel of said current pixel (S432):
• if the pixel is not a source pixel, assigning (S433) the source indicator of said neighboring pixel to said current pixel;
• assigning (S434), to the value of the intensity extremum of the second type on the path between the source associated with the pixel and the current pixel, the extremum of the second type between:
• the value of the intensity extremum of the second type on the path between the source associated with the neighboring pixel and the neighboring pixel;
• or
• the intensity of said pixel.