# An app that reads music? **URL:** \ **Category:** Factual Questions\ **Created:** [July 18, 2020, 6:38pm UTC](https://boards.straightdope.com/t/an-app-that-reads-music/915692 "2020-07-18T18:38:49Z")\ **Posts on this page:** 6\ **Page:** 1
**Author:** ![jsc1953](https://avatars.discourse-cdn.com/v4/letter/j/5daacb/32.png) [@jsc1953](https://boards.straightdope.com/u/jsc1953)\ **Post date:** [July 18, 2020, 6:38pm UTC](https://boards.straightdope.com/t/an-app-that-reads-music/915692/1 "2020-07-18T18:38:49Z")
Is there an app, where I can point my phone’s camera at a fragment of musical notation and the melody would play on my phone? if not, why not? ---
**Author:** ![Thudlow\_Boink](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/thudlow_boink/32/320_2.png) [@Thudlow\_Boink](https://boards.straightdope.com/u/Thudlow_Boink)\ **Post date:** [July 19, 2020, 4:18pm UTC](https://boards.straightdope.com/t/an-app-that-reads-music/915692/2 "2020-07-19T16:18:49Z")
It looks like there are apps that can read and play sheet music. I don’t have any knowledge or experience of them, but here are some links to information I found: > **[The Best Music Scanning Software and Apps in 2022](https://www.musicrepo.com/music-scanning-software/)** > > Compare best music scanning software & apps in 2021. Convert sheet music to MIDI, play back, export to notation software. Inc video tutorials > **[Optical music recognition](https://en.wikipedia.org/wiki/Optical_music_recognition)** > > Pages for logged out editors learn more > > > > Optical music recognition (OMR) is a field of research that investigates how to computationally read musical notation in documents. The goal of OMR is to teach the computer to read and interpret sheet music and produce a machine-readable version of the written music score. Once captured digitally, the music can be saved in commonly used file formats, e.g. MIDI (for playback) and MusicXML (for page layout). > In the past it has, misleadingly, also be... ---
**Author:** ![Hari\_Seldon](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/hari_seldon/32/5173_2.png) [@Hari\_Seldon](https://boards.straightdope.com/u/Hari_Seldon)\ **Post date:** [July 19, 2020, 5:01pm UTC](https://boards.straightdope.com/t/an-app-that-reads-music/915692/3 "2020-07-19T17:01:33Z")
I’ve seen musicians (e.g. all four members of the Dover quartet) use tablets to display the music. But they have to advance the page with a foot pedal and I have wondered if it would be possible for the software to follow the music and advance the page automatically. Of course, there could be a problem with repeats, but I imagine that could be programmed beforehand. ---
**Author:** ![jsc1953](https://avatars.discourse-cdn.com/v4/letter/j/5daacb/32.png) [@jsc1953](https://boards.straightdope.com/u/jsc1953)\ **Post date:** [July 19, 2020, 5:17pm UTC](https://boards.straightdope.com/t/an-app-that-reads-music/915692/4 "2020-07-19T17:17:59Z")
T\_B…thanks for the links! PlayScore does exactly what I was looking for: you snap a picture of the score, and it plays it back instantly (using piano tones). The free version only allows two staves, but that’s fine for my purposes. ---
**Author:** ![si\_blakely](https://avatars.discourse-cdn.com/v4/letter/s/d9b06d/32.png) [@si\_blakely](https://boards.straightdope.com/u/si_blakely)\ **Post date:** [July 20, 2020, 3:47am UTC](https://boards.straightdope.com/t/an-app-that-reads-music/915692/5 "2020-07-20T03:47:16Z")
> [@Hari\_Seldon](#): > > I have wondered if it would be possible for the software to follow the music and advance the page automatically. Of course, there could be a problem with repeats, but I imagine that could be programmed beforehand. Polyphonic music recognition is not trivial, but it is possible - I have implemented code (not mine) that recognises chords in an audio stream, and the same basic principle (a Constant-Q Fourier Transform) can be extended to the entire range of musical notes. I’m actually not even sure I’d do that, though. A _chromagram_ is a 12-point graph that plots notes from C to B by summing the octaves. You can calculate the approximate _chromagram_ at any point from the score, and compare it to the _chromagram_ of the audio, and make a pretty good attempt at tracking the progress. Add in some beat-matching to compute the tempo, and I suspect it would work pretty well. I’ll have to play … ---
**Author:** ![sbright33](https://avatars.discourse-cdn.com/v4/letter/s/8e8cbc/32.png) [@sbright33](https://boards.straightdope.com/u/sbright33)\ **Post date:** [July 22, 2020, 4:08pm UTC](https://boards.straightdope.com/t/an-app-that-reads-music/915692/6 "2020-07-22T16:08:57Z")
I wrote the first app for this in 1989 with Musitek