In considering application of digital signal processing techniques to speech communication problems, it is helpful to focus on three main topics: the representation of speech signal in digital form , the implementation of sophisticated processing techniques, and the classes of applications which rely heavily on digital processing. The objective analysis of the signal in terms of its various parameters is of primary concern. Pitch and Intensity are the most important parameters of a sound signal. Characteristics of a sound signal can be defined by observing the waveforms of pitch and intensity. A Spectrogram gives an efficient representation of the signal. Vowels and consonants can be separated by measuring the formant frequencies measured from the spectrogram.

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Intensity Spectrogram Pitch Speech Formant Vowels Frequency.