1. An automatic speech recognition system for recognizing a user voice command in noisy environment, comprising: matching means for matching elements retrieved from speech units forming said command with templates in a template library library; processing means including a MultiLayer Perceptron for computing posterior templates (P(O template(q) )) stored as said templates in said template library; means for retrieving posterior vectors (P(O test(q) )) from said speech units, said posterior vectors being used as said elements; calculating means for automatically selecting posterior templates stored in said template library, wherein said calculating means use a graph approach, such as the Gabriel's approach, or the relative neighbour approach, or a linear interpolation to prepare posterior templates from training templates.