Tuesday 25 September 2007

Beatles Chord Transcriptions


Chris Harte from the C4DM announced last night that he completed his amazing effort of transcribing the chords for all songs on the 12 studio albums of the Beatles. The transcriptions are extremely high quality. Anyone who wants a copy just needs to contact him. This will definitely boost research in any direction related to chords (chord recognition, chord progressions, harmony analysis...). It's also a good excuse for any research lab to buy the complete Beatles collection. Btw, don't forget to cite his work when you use his annotations! ;-)

Below are excerpts from the two emails he sent to the music-ir mailing list, so that Google can index them (Afaik he hasn’t set up a website for this yet).

(Chris' email is christopher dot harte at elec dot qmul dot ac dot uk).

Chris Harte wrote in his first email (Sep 24, 2007, 9pm):


[...] I have just completed work on the full set of chord transcriptions for the beatles songs from all 12 studio albums.

The verification was done by synthesizing the transcriptions in MIDI then putting that back together with the original audio (with correct timing and tuning) so that people could spot any errors by listening through to them.

Hopefully, after the verification process that we have just completed, these transcriptions should now be accurate enough to serve as a ground truth for various kinds of chord and harmony work in the MIR field.

If you would like a copy of the new version of the collection then please let me know and I will send them to you. [...]


Chris Harte wrote in his second email (Sep 25, 2007, 4am):


[...] To clear up a few things:

The transcription files are in wavesurfer ".lab" format which is just flat text arranged like this:

Start-time end-time label
Start-time end-time label
Start-time end-time label
...

Times are in seconds.

".lab" files can be opened as a transcription pane in wavesurfer (I have made a wavesurfer conf file set up for showing these transcriptions nicely if people need one) and also in Sonic Visualiser as an annotation layer (use "A point in time" for the "each row specifies" option when loading in sonic visualiser).

The chord symbols used in the transcriptions basically conform to the syntax described in our ISMIR 2005 paper "Symbolic Representation of Musical Chords: A Proposed Syntax for Text Annotations" available here:
http://ismir2005.ismir.net/proceedings/1080.pdf

There has been one slight change to the syntax described in this paper which is that now a chord symbol, which is defined as a root and a list of component degrees, should not automatically be assumed to include the given root note unless the '1' degree is explicitly included in the list
- e.g. C major can be written C or C:maj which are both equivalent to writing C:(1,3,5) so the "major" pattern should be (1,3,5) instead of just (3,5). This makes it possible to annotate a chord where it is obvious that the intended harmony is C major even though only the notes E and G are present by using C:(3,5). I hope that makes sense...

For those who do not already know, I have written a set of tools for manipulating these chord symbols in matlab (they don't use any toolkits so I guess they should also work fine in Octave) - if you would like a copy of those then let me know. There will be an updated version of these tools available soon as well.

For more information on the chord symbols, chord tools and transcription process, my long awaited (long awaited by me at any rate...) PhD thesis will include a whole chapter about it all. I hope to submit the thesis sometime around christmas this year. [...]

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