(Fast Fourier Transform) A computer algorithm used in digital signal processing (DSP) to modify, filter and decode digital audio, video and images. FFTs commonly change the time domain into the frequency domain. For example, FFTs are widely used in voice recognition and myriad other pattern recognition applications. They are used to sharpen edges and create effects in static images and are widely used to turn a number series into sine waves and graphs.|
The FFT quickly performs a discrete Fourier transform (DFT), which is the practical application of Fourier transforms. Developed by Jean Baptiste Joseph Fourier in the early 19th century, the Fourier equations were invented to transform one complex function into another. One of Fourier's primary goals was to predict the rate of heat transfer based on temperature, mass and proximity. In practice, the terms FFT, DFT and Fourier transform are used synonymously. See DSP.
A Fourier transform was used to chart the power levels at different frequencies from the half second of digital samples (top).