If you regularly learn or transcribe songs from audio, deCoda might be just the helping hand you need.
While zplane are perhaps best known for the time‑ and pitch‑shifting technology that is often licensed by other music/audio software developers, they also have a range of their own products. Their latest release is deCoda, a standalone application and, while it obviously depends very much on zplane’s considerable expertise in the manipulation of audio, it applies that expertise to a very different task; identifying the key, tempo, chords and major structural elements (verse, chorus, etc) of a song from an audio file.
However, as described more fully below, using some clever spectrographic analysis, deCoda can also go deeper than this and allow you to visualise note data from individual instruments within the mix. So, if you regularly transcribe or learn songs from audio, might deCoda speed the process?
DeCoda can work with wav, aiff, mp3, wma, flac and ogg formats. On import, deCoda spends a few seconds analysing the file before displaying the main waveform view in the central portion of the window. Above this are the Parts and Chords Lanes. The former shows deCoda’s best guess at dividing the song into sections while the latter shows the suggested chords.
Of course, getting software to make decisions about song structure or extract chords and chord changes from a full mix is a pretty significant ask. I tested deCoda with a range of commercial tracks and a few piano‑only performances of varying degrees of chordal complexity. The results were perhaps similar to other chord recognition software I’ve experienced and new users perhaps should not expect analysis of jazz classics to appear fully formed. However, with pop or rock based mostly upon major and minor chords, the results will be more than good enough to get you started in ‘decoding’ the song.
You can manually edit the contents of both lanes to refine the automatic detection. On this front, during the review period, I received the update to deCoda v.1.1 and one of the main...