# Player Piano Roll (自動ピアノロール)

> The rolled paper medium on which punched holes are the performance itself. The turn from scores read by people to codes read by machines — ancestor of the punch card and the digital sequencer.

- IndexStyle No.424 — https://indexstyle.org/styles/player-piano-roll
- Kind: Style · Family: Notation Systems · Era: 1896–1930s
- Mood: Technology, Nostalgia, Play
- Color cues: #e9e6dd / #67635d / #171615 (cues taken from reference works, not a fixed palette)

## Defining characteristics

- Rows of perforations
- The scrolling roll
- Machine-readable music
- Performance physically recorded

## Best used for

- Comparing primary sources and canonical works
- Extracting principles that transfer to other media

## Research method

This entry records a historical style; derive the treatment from its sources rather than a fixed recipe:

- Observe the letters, signs and scale of reference works
- Extract the one structure that governs gaze and information
- Verify the materials and behaviors specific to era, region and process

## What to avoid

Don't reduce it to surface signs. Verify the context of era, region, technology and makers.

## Application checklist

Before calling a piece an application of this style, check it against the defining characteristics:

- [ ] Rows of perforations
- [ ] The scrolling roll
- [ ] Machine-readable music
- [ ] Performance physically recorded
- [ ] At least one reference work below has been studied directly
- [ ] The caution above ("What to avoid") has been addressed

## Related styles

- **Barcode & QR (バーコードとQRコード)** — Machine-readable graphics printed as stripes and square grids. DENSO WAVE's QR solves orientation with three corner finder patterns — a pattern to be read, inspired by Go boards and halftone screens, now part of the everyday landscape. → https://indexstyle.org/styles/barcode-qr
- **Ise Katagami (伊勢型紙)** — Dyeing stencils cut from persimmon-tannin laminated paper: drill, tool and stripe cutting produce continuous patterns so fine that the stencils themselves startled fin-de-siècle Europe as an art of line. → https://indexstyle.org/styles/katagami

## Further study

- the Welte-Mignon
- Gershwin's own rolls
- the lineage to MIDI

## Reference works

- 自動ピアノのロール（CC BY-SA 4.0） — https://commons.wikimedia.org/wiki/File:PlayerPianoRoll.jpg
- ヴェルテの再生ピアノ（CC BY-SA 3.0） — https://commons.wikimedia.org/wiki/File:Weltereproduktionsklavier.jpg

## Source of record

- The Pianola Institute — https://www.pianola.org/

## Machine surfaces

- JSON: https://indexstyle.org/api/styles/player-piano-roll
- Image-generation prompt (legally clean): https://indexstyle.org/styles/player-piano-roll/prompt.txt
- MCP: https://indexstyle.org/mcp (tools: search_styles, get_style, compose_styles; prompts: image-prompt, apply-style)

## 日本語

紙に開けた穴が演奏そのものになる巻紙の記録メディア。人が読む楽譜から機械が読む符号への転換点で、パンチカードとデジタルシーケンサーの先祖にあたる。

特徴: 穿孔の列／巻紙のスクロール／機械可読の音楽／演奏の物理的記録
注意: 表面的な記号へ還元せず、時代・地域・技術・制作主体の文脈を確認する。