Abstract: The invention relates to a neural network for semantic segmentation of a document with complex text. The network comprises a first multilayer neural encoding chain of an initial image file of the document to be processed, a second multilayer neural encoding chain of a mask image file of the document to be processed, a multilayer neural decoding chain connected to the outputs of the first and second encoding chains, a first bridge of parallel residual connections between the layers of the first encoding chain and the layers of the decoding chain, a second bridge of parallel residual connections between the layers of the second encoding chain and the layers of the decoding chain, the residual connections generating files of the same size that are connected after a layer of the neural decoding chain generating a file of the same size.