Scoreon

Scoreon is a Chrome extension that helps you capture visible sheet-music or tablature frames from educational videos and export them into clean PDF or OMR-ready image packages for personal study.

I built this as a practical study tool: select the part of the video where the score appears, let the scanner collect the useful frames, clean up the result, and export it in a format that is easy to read or pass to an OMR workflow later.

What it does

• Opens a scanner in a new tab.
• Uses the browser's normal screen/tab/window capture flow.
• Lets you draw a crop area over the score or tablature.
• Samples frames at a configurable interval.
• Filters out frames that do not look like sheet music or tablature.
• Removes near-duplicates using a simple visual signature.
• Auto-trims large white space and common black bars.
• Lets you add optional labels per captured snippet, such as Intro, Verse, or Chorus.
• Exports a clean PDF.
• Exports a PNG ZIP.
• Exports an OMR Package with clean PNG files, black/white OMR-ready PNG files, a preview PDF, and metadata.

What it does not do

• It does not download videos.
• It does not bypass DRM or platform restrictions.
• It does not convert images directly to MusicXML inside the extension.
• It does not know whether a score is copyrighted. Use it only with material you own, have permission to use, or are legally allowed to process.
• The score detector is a visual heuristic, not a full AI model. It can miss frames or keep the wrong ones depending on the video.

Install as an unpacked Chrome extension

1. Download or clone this repository.
2. Open Chrome and go to chrome://extensions.
3. Enable Developer mode.
4. Click Load unpacked.
5. Select the scoreon project folder.

Languages

Scoreon currently supports English, Greek, and Spanish through Chrome's built-in extension localization system (_locales + chrome.i18n).

Spanish support is currently AI-generated.

Basic workflow

1. Open the video you want to study.
2. Click the Scoreon extension button.
3. Click Open scanner.
4. In the scanner, click Start capture.
5. Choose the tab or window that contains the video.
6. Drag over the area where the score or tablature appears.
7. Click Start scan.
8. Let the video play.
9. Click Stop.
10. Delete any bad captures and add optional labels.
11. Export as PDF, PNG ZIP, or OMR Package.

Export options

PDF

Good for reading, printing, or keeping a quick study sheet. The default orientation is A4 portrait.

PNG ZIP

Exports each saved snippet as a separate PNG file. This is useful if you want to edit the images manually or use them somewhere else.

OMR Package

Exports a ZIP like this:

Song Title/
|-- original/
|   |-- 001-original.png
|   `-- 002-verse-original.png
|-- omr/
|   |-- 001-omr.png
|   `-- 002-verse-omr.png
|-- preview.pdf
|-- project.json
`-- README.txt

The omr/ folder is meant for tools like Audiveris or homr. The usual workflow is:

Scoreon -> OMR Package -> Audiveris/homr -> MusicXML/MXL -> MuseScore Studio

The OMR result will still need checking. Screenshots from videos are not the same thing as a clean scan.

Recommended starting settings

• Frame interval: 500 ms
• Change threshold: 12
• Duplicate threshold: 5
• Minimum time between saves: 900 ms
• PDF orientation: A4 portrait
• PDF mode: Compact
• Score detector: enabled
• Minimum score-like confidence: 48
• Auto-trim: enabled
• Padding: 18 px

If it keeps random frames, increase the minimum score-like confidence to 55-65. If it misses valid score frames, lower it to 35-45. If it keeps too many duplicates, increase the duplicate threshold or the minimum time between saves.

Notes for public use

Scoreon is designed as a local capture/export helper for personal study. It does not upload your captures anywhere and it does not download source videos.

Please use it responsibly with material you are allowed to process.

Version

1.0.0