Help with DrumSheetScanner

Getting started

1. Scan a page Tap Scan sheet and line the drum notation up inside the A4 frame, or use Import from gallery for a photo you already took. The torch button helps under bad stage lighting.
2. Choose the bars After the scan you get a preview of the detected bars. Select the ones you want and add them to a new session or to one you already have.
3. Play and correct The bars appear as a step grid. Press play, follow the cursor, and tap any cell that is wrong. The grid is the source of truth from that point on.
4. Export Open Export & Share, pick MIDI, WAV or MP3, and send it wherever you need it through your device's share sheet.

Scanning tips

The detector was trained on photographs of real pages, but it still reads best when the page is easy to read. In order of how much difference they make:

• Flatten the page. A curled or folded sheet bends the staff lines, and bent staff lines are the single biggest cause of missed notes.
• Fill the frame. Keep the staff inside the A4 guide and get close enough that the noteheads are clearly separated.
• Shoot straight on. Photographing at an angle squashes the note spacing and confuses the beat positions.
• Even light, no shadow. Your own shadow across the lower half of the page is a common one. Move, or switch the torch on.
• Faint photocopies still work. The app lifts a low-contrast page before reading it, so a pale copy is worth trying rather than rescanning at another exposure.

Frequently asked questions

Does the app need an internet connection?

No. Scanning, note detection, playback and export all run on your device, and the app works in aeroplane mode. There is no account and nothing to sign in to.

Which sheet music can it read?

Standard drum-set notation on a five-line staff: kick, snare, toms, hi-hat and cymbals, including accents and ghost notes, with open hi-hats written as a marker above the beam. Time signatures from 2/4 and 3/4 through 4/4, 6/8 and odd meters such as 5/4 and 7/8 are supported, at quarter, eighth, triplet and sixteenth resolution.

Handwritten charts, tab-style notation and heavily stylised engravings are much harder for the detector and may need more correcting by hand.

It says "No staves detected". What now?

That means the app could not find the five staff lines in the photo at all, which is almost always a framing or lighting problem rather than a notation one. Retake the shot straight on, fill the A4 frame with the staff, and make sure no shadow crosses the page. If the page is very pale, try the torch.

Some notes are missing or on the wrong line.

No detector reads every page perfectly, which is why the step grid is fully editable. Tap an empty cell to add a hit, tap a filled one to remove it, and use the pattern settings to switch the row's articulation. Your edits are what gets played and exported.

If a page comes out badly, please send it in — see reporting a bad scan below. Real pages that the detector got wrong are the most useful thing you can contribute.

Why is there no MP3 export on my iPhone?

MP3 encoding relies on a library that cannot be shipped in the iOS build for licensing reasons, so iOS offers MIDI and WAV instead. WAV is lossless and imports into every audio app; if you need a smaller file, converting the WAV on a computer takes seconds.

What can I do with the exported files?

The MIDI export is a standard MIDI file with General MIDI drum mapping, so it opens in any DAW, in notation software such as MuseScore, and in GarageBand. WAV and MP3 are rendered with the soundfont bundled in the app, so they sound the same as playback did.

Where are my scans and patterns stored, and how do I delete them?

In the app's own storage on your device. Delete a single page or a whole session from the sessions list — deleting a session removes its bars and the scanned pages with it. Uninstalling the app removes everything it has saved.

Can I keep a whole song together instead of single bars?

Yes. A session holds as many pages as you scan into it, and playback can run a single pattern or the whole session end to end. Sessions can be renamed, and new pages can be added to an existing one at any time.

Playback is silent or stutters.

Check the device volume and the app's own playback volume in the settings sheet — the app volume sits on top of the system one. If audio stutters, close other audio apps that are holding the output, and try toggling playback off and on again. If it persists, tell us your device model and Android or iOS version.

Does the app work on my device?

It needs Android 7.0 (API level 24) or newer, or iOS 16.0 or newer, and a camera if you want to scan rather than import photos. Note detection is processor-intensive, so it runs noticeably faster on recent hardware.

What does the app cost?

DrumSheetScanner is free at the moment. There are no adverts, no in-app purchases and no subscription, and nothing in the app is locked behind a payment.

Reporting a bad scan

The app can package up a page that did not scan well, together with the corrections you made to it, and let you send it in. Open the export screen and use the correction export section. Before anything is sent you get a summary of exactly what the bundle contains — how many pages, how many photos and how large it is — and nothing leaves your device until you pick a destination in your own share sheet.

The bundle includes the photographs of the pages concerned, so only send pages you are comfortable sharing. Copyrighted sheet music stays your responsibility to handle appropriately.

Reporting any other problem

Writing to wockibytes@gmail.com with these four things makes a fix far more likely:

• Device model and Android or iOS version
• The app version, shown in the settings sheet
• What you did, what you expected, and what happened instead
• A screenshot, or the photo of the page if it is a scanning problem

Privacy and licences

DrumSheetScanner collects nothing about you and sends nothing anywhere; the privacy page sets out exactly what the app touches on your device and why. The open-source components it is built on are credited under Credits & licences in the app's settings sheet.