Web basic-programming.blogspot.com

    Saturday, November 05, 2005

    Frames Representation of Speech Signal

    Frame-based data is a common format in digital computers. Data acquisition hardware often operates by accumulating a large number of signal samples at a high rate, and propagating these samples to the digital computer as a block of data.

    There are some reasons of doing frame processing. Firstly, some time-properties of the signal are easier to be seen in frames. For example, the energy level of a speech signal for a period of time is analyzed in frames for a few milliseconds. Secondly, most of the analyses in frequency domain, for example, short-time Fourier transform, needs the data to be in blocks, or windows. Another advantage of frame analysis is the application in real-time system. The frame processing maximizes the efficiency of the system by distributing the fixed process overhead across many samples; the fast data acquisition is suspended by slow interrupt processes after each frame is acquired, rather than after each individual sample. Typical values of parameters are applied for the frame processing in which frame size is 256 samples with the overlapping of 64 samples for the 8 kHz signal. The figure below illustrates a segment of speech signal is split into frames with 256 samples per frame and 192 overlapping.

    1 Comments:

    Blogger Monty said...

    Are there practical applications of Speech Recognition today?

    8:33 AM  

    Post a Comment

    << Home

    Web Site Counter
    Online Schools