Remember Microsoft Songsmith? “U.S. Patent & Trademark Office has awarded Microsoft a patent for the technology, under the title of "Automatic accompaniment for vocal melodies.",” revealed. From the abstract: “A method for generating an accompaniment for a recorded audio melody includes providing a recorded audio melody that includes segments; performing a frequency analysis of the recorded audio melody; summing the total duration of each fundamental frequency within a segment of the melody; based on the summing, computing a probability for each possible chord for each segment; based on the computed probabilities, selecting a set of chords for the segments; and outputting the set of chords as an accompaniment for the recorded audio melody.” The rest of the patent text makes reference to "My Song," which was the project name under which Songsmith was developed, before it was turned into a product.