· 6 years ago · Sep 14, 2019, 01:16 AM
1Outline
2
3Transposing music is a great musical skill to have. Absolute pitch is
4less important; what is more so important is hearing and having relat-
5ionships between notes. However, the range of notes may mean keys must
6be adjusted, and many instruments in bands are transposed instruments,
7where different keys are easier to play, and different concert pitches
8are even notated differently.
9
10Transposing solutions certainly already exist. If music exists in a
11digital format, it is almost trivial to have any competent music program
12do the transposing or pitch editing for you. Musical training also means
13that you can hand transpose music. However, both these options take time.
14As a band director that wants to double check transpositions of a 200
15page 16 part score; A music ed teacher, who wants to help all his stu-
16dents learn notes; as music hobbiests who want to change to a key with
17less flats or sharps to play easier; there are many use cases where
18simple, fast transcriptions are simply not avaliable. Not all music is
19digital: some music may even have copywrite restrictions on permanantly
20storing a file.
21
22We propose an app that will take a picture of whatever you want to tran-
23spose, and based on how many semitones/key sigs you want to change,
24will do that automatically for you.
25
26This involves 3 basic parts:
27
281. Convert Picture to digital music format
292. Transposition
303. Convert digital music format back to picture.
31
32Under our research, each of these three components exist individually.
33The mega site IMSLP hosts countless historical music scores, and digit-
34ally catelogs many with OMR (Optical Music Recognition) technology.
35Programs like LMMS, Audacity, FL Studio, and many more transpose music
36easily. And the program MuseScore, a music notation software, has the
37ability to change digital music formats to a visual pdf score.
38
39However, it appears that these three steps have never been combined into
40a simple, quick, useful solution to real-time transcriptions of music.
41
42Our project automates these three steps into one powerful web-app, acce-
43ssable by any electronic device capable of connecting to the internet,
44including phones and tablets.
45
46The front-end gathers details such as the current key and the desired
47semitone change/transposed key (necesary for correct enharmonic label-
48ing), and of course, the image file of the music score. Then the back
49-end does several steps:
50
511. Crops (Thresholds) and transforms image into rectangle. (Automated
52using Open CV) [1]
53
542. Change image to PDF through API [2]
55
563. PDF through OMV to MusicXML [3]
57
584. Transpose MusicXML using scripts [4]
59
605. MusicXML to other formats [5]
61
62Data between the front-end and back-end will be sent using either AJAX
63or JQuery, and received and processed with either NodeJS or Bash on an
64Apache server. Proper CGI, user-friendliness, and responsive UI/UX is
65attempted. Strech goals including displaying original and transposed
66side by side, playing audio file, and transposing different parts of
67the score to different keys. For copyright compliance, digital files
68will not be able for public download, and all files will be marked at
69the end of each session and removed periodically.
70
71
72Sources:
73[1] https://docs.opencv.org/trunk/da/d54/group__imgproc__transform.html
74[2] https://github.com/ConvertAPI/convertapi-cli
75[3] https://github.com/Audiveris/audiveris
76[4] https://www.musicxml.com/tutorial/the-midi-compatible-part/pitch/
77[5] https://musescore.org/en/handbook/3/command-line-options