Digital Music Display for My Organ

[stefanv]

I've put this in Home Organs even though mine is a Hammond as a I figure this might be of more general interest.

Over the last few weeks, I've been working on adding a digital sheet music display to my organ. The display itself is a 21" HP monitor I picked up used for $40. It is mounted in place of the music rack on my (home made) organ-top synthesizer. The software is still under development (I want to add the ability to add annotations), and is running on a Raspberry Pi 3.





One thing still missing is a convenient way to turn the page. I've got a small keyboard on order that should exactly fit on the organ's lower-left cheek block, but I'd like to add either some foot switches, or some sort of gesture controller, to make it easier. Unfortunately, the screen is not a touch screen, so tapping won't work.

Once the software's done, I plan to place it on GitHub.

[AllenAnalog]

A very interesting project to tackle. I'll be interested to see how far you go with it.

Allen Organ Company has been offering a "Page Turn Kit" on their consoles since at least 2014. And there was a previous thread on the Forum about this subject in 2016.

https://organforum.com/forums/forum/...e-turn-feature

One of the products mentioned there, the Air Turn ATR-104 unit, is for Mac or Windows PCs and could be hard-wired to one or two toe studs for page turns.

https://www.airturn.com/products/air...04-page-turner

Obviously using a PC is more hardware than your intended solution but given the logical appeal of such a device I suspect there may be others out there who have found ways to make this product work with tablets of some kind.

[voet]

Stefanv, what a great concept. Clearly you have more technical ability than I do.

I have an idea that I wonder if anyone has thought of. I would like software that would track where you are in the piece (using MIDI) and move the score as you are playing. This approach would not require any additional intervention by the performer. There would need to be a way to handle repeated sections and also allow for the player to omit a repeat if they wanted to. However, if a GPS can adapt its route based on the route a driver takes, it should be possible for a music program to do the same.

[AllenAnalog]

Bill, did you see the note about the Apple app in the Forum post I linked above? Not MIDI based but "listening" based.

[voet]

Thank you for alerting me to it, AllenAnalog. It looks like it runs on an Apple IPad. One advantage of this product is that it can "read" a PDF. This really opens up the possibilities greatly. I do not own any Apple products, so I would have to invest in an IPad if I wanted to use this. I would really like to try it before making that investment.

[Eric Mack]

I'm interested in what you are doing with the Raspberry Pi. A wood frame/trim around the monitor would make it even more convincing.

I'm assuming (perhaps incorrectly) that is it acting as a browser to a network file share where you keep your music?

Are you just displaying images, or PDF? or are you using something like MUSESCORE to to display your music?

[stefanv]

At the moment, the music is all kept locally on the Pi (there's plenty of space on the 32GB microSD card), but it could be anywhere. The program accepts both PDFs and images (PNG, TIFF, JPEG, GIF, and BMP), and merely finds all such files in the the specified directory(s) and presents an alphabetical list of all the titles. The name of the file is expected to be the title (e.g. "Let It Be.pdf"), and in the case of image files, a series of numbered files is assumed to be multiple pages comprising one score (e.g. "Let It Be-1.png", "Let It Be-2.png", ...). For speed reasons, each score is pre-processed into cropped screen-sized images in a hidden subdirectory the first time it is opened, and those are kept around so that subsequently opening the same score is fast unless you've made changes to the original source (e.g. replaced a scan with a better one).

[Eric Mack]

Stephan, I have an HP 21" monitor similar to yours, but it has a touch screen. I think mine is not capacitance based but uses a ring of IR sensors in the glass. In any case, I would imagine you can pick these up inexpensively. This would allow you to easily do a swipe right/left. If not, something like an Airturn could work for you or some other switch sensor. I know there is even a gesture sensor available for Arduino. I will enjoy following this project. Do post if you plan to share code.

[tucsondave]

Stefanv, what a great concept. Clearly you have more technical ability than I do.

I have an idea that I wonder if anyone has thought of. I would like software that would track where you are in the piece (using MIDI) and move the score as you are playing. This approach would not require any additional intervention by the performer. There would need to be a way to handle repeated sections and also allow for the player to omit a repeat if they wanted to. However, if a GPS can adapt its route based on the route a driver takes, it should be possible for a music program to do the same.

OrganMuse has been doing that for years. But pricey.

[voet]

Thanks for the info, Tucsondave. I went to their website, but they do not list pricing. It certainly has a lot of functionality.

[stefanv]

"OrganMuse system pricing is coming soon!" So they said. In 2012. Abandonware?

[Silken Path]

It's not home-brew, and not having such skills (but I admire that you can do that), but here's a 24" ViewSonic touch screen sitting in place of the (easily removed) music rack on my W5000C. I'm just getting started at digitizing my sheet music, which is mostly 70's vintage. I have a Gator carrying case for the monitor and can also use it with my piano, reed organ (!), and Conn theater organ. The '67 Allen is going to require some reinforcement of the music deck, as the monitor weighs 15.5 lbs. That's PDF-Xchange Editor running on my ThinkPad. I have a smaller ThinkPad (13" Yoga education version) that it will also work with, but the bigger one can run Hauptwerk. For the time being, I'm using the HP software that came with an inexpensive DeskJet All-in-One for scanning - it can do a maximum of 200 PPI for multi-page documents, but the file sizes when combined can still easily be hundreds of megabytes.

[Warrentdo]

Hello Silken, have you tried adjusting the scan. just scanning at 600DPI in just black and white should be around 300kb a a4 sheet.
colour or grayscale are bloughters.

[Eric Mack]

Stefan, this may be of interest if you have need to have the switches be wireless (not sure that has as much application with an organ) Bluetooth Foot switch Interfacing

[johnbeetem]

I'm interested in what you are doing with the Raspberry Pi. A wood frame/trim around the monitor would make it even more convincing.

I seem to remember a project from the 1970s or 1980s where someone made a primitive touch-screen by putting IR LEDs and photodetectors on opposite sides of a wooden frame. Your finger would block two of the beams and a microprocessor switching the LEDs and scanning the photodetectors could figure out where your finger was. I think it was in Byte magazine, but not sure. A simplified version of this would work nicely.

[stefanv]

I seem to remember a project from the 1970s or 1980s where someone made a primitive touch-screen by putting IR LEDs and photodetectors on opposite sides of a wooden frame. Your finger would block two of the beams and a microprocessor switching the LEDs and scanning the photodetectors could figure out where your finger was. I think it was in Byte magazine, but not sure. A simplified version of this would work nicely.

I remember that as well, and such frames, with much higher resolution, are actually available for purchase (although a bit pricey for my liking). But yeah, a simplified version that divides the screen into two touch sensitive areas would be sufficient for this case.

[stefanv]

I think what I'm going to do for now is simply reserve two of the buttons on the synthesizer control panel (the synth runs on its own Raspberry Pi) as page turn buttons, and forward these to the music display Pi (probably via wires). The buttons are pretty easy to reach and press (far easier than turning paper pages).

[musicmaker84]

While not as elegant, I use Foxit PDF Reader in view mode and have the PC keyboard leaning against the music rest. Easy enough to flip pages quickly enough. I evaluated MusicReader but found Foxit served my purposes even better.

[stefanv]

Just an update on this project. I've been doing a lot of work writing software to clean up bad scans (dirty, crooked, bad contrast, show-through from the other side of the page, yellowed paper, etc.) and turn them into something presentable. Here's a scan of part of a piece of music (I don't want to post the whole thing to avoid copyright infringement) out of a book I bought in 1978. The actual scan was at 300dpi, but I've scaled it down for display here.

Notice that the paper is yellowed, the contrast isn't very good, the scan isn't straight, and it's cropped too close to the edge at the bottom. Without any manual intervention, this is what my music display software displays, full size for display on a 1920x1080 screen:

The goal of the program is to make the music as large as possible while still fitting two pages on the display, and leaving a small margin around the edges for aesthetics. To this end it does two passes of colour correction (one to use the full range of available colours before performing other corrections, and the second to produce reasonable contrast), trims and/or pads edges as necessary, straightens the image, and sharpens it a bit. The edge trimming operation was carefully designed to cut off irrelevant information that would cause the music to display smaller than necessary. As a result, the displayed score is often as large or larger than the original paper copy. Here's a low-resolution side-by-side of the original scan and the final output:

Finally, here it is in real life:

[Bruce.Simonson]

Excellent work. Have you had a chance to post to github? I have a couple Raspberry Pi's sitting fallow, and I would like to give this go. Thanks for sharing; again, looks like fine work, that meets a real need.

-Bruce

[stefanv]

Hi Bruce. I'll post it when it's done. Should be up in a week or two.

[Warrentdo]

Fantastic, really fantastic. that does look good for 300DPI if you want a tester im more than happy to help :-) keep up the good work.

[Eric Mack]

If you haven't looked at at Microsoft Lens, yet, do. They use a method computation photography to capture, flatten, reorient images as if you had a perfect scan on flat glass -- in less time than you could load a sheet of paper in a scanned. Runs on iPhone (and possibly Android)