The invention relates to a scheme of realizing network
speech recognition in an English oral language
machine examination
system. According to the scheme, traditional
spectral subtraction (SS)
noise reduction technology and cepstral mean normalization (CMN)
noise reduction technology are improved, combined with a probability scale DP identification method of a continuous state
hidden Markov model(HMM), the invention provides a network
speech recognition scheme of unspecified people in an English network examination
system, and by utilizing the scheme, a network
speech recognition apparatus in a physical environment is realized. By employing the above method, an SS method with input amplitude spectrum self-adapting and a CMN method based on progressive adaptive mode MAP
algorithm are combined, and influence of ambient
noise on an
identification system is substantially reduced. Simultaneously, according to the scheme, based on a traditional DP method, by utilizing a DP
algorithm of probability scale, recognition is carried out, thus a DSP speech recognition apparatus can be applied to speech recognition of unspecified people of different outdoor occasions, and a
recognition system scope and recognition precision are raised.