MEA - Spectrum Measurement Program

I. General Description

This program displays spectra, one at a time, from a waveform file. It is designed to step through the file or move randomly about the file to allow measurement of speech parameters. Each spectrum is displayed with estimated envelope and formant frequencies. Most variations in the way that the spectrum is computed are under program control and can be set with commands. This allows considerable variation in the way that the program can be used. Additionally, the program has the capability of opening an auxiliary log file. When a log file is open, formant frequency estimates and associated amplitudes can be written to the file for any frame that is being viewed using the SAVE command. The data for each frame is written to the file as a list of numbers on one line. The first value is the time offset of the frame given in msec from the start of the file. The remaining numbers are in pairs with the first number being a frequency and the next number an amplitude at that frequency. The first 5 such pairs pertain to the first 5 formants (F1 - F5) respectively. The final two pairs are an additional pole and spectral zero, as for example might be present with a nasal sound. All of these numbers are simply the frequency estimates the program has demarked in the display with arrows. The program guesses the right values for each, but it is your responsibility to see that they are actually set correctly. Specific commands that can be given, subcommands, and comments about what they all mean follow.

II. Command Summary

OPEN -- Open a log or waveform file

SAVE -- Save current data to logfile.

CLOSE -- Close the log file

EXIT -- Exit the MEA program

<time> -- Position display to specified time

<return> -- STEP to next analysis frame

HELP -- Show help screen

SET -- Set various program options

MARK -- Mark formants