76 lines
4.8 KiB
Markdown
76 lines
4.8 KiB
Markdown
---
|
||
type: research
|
||
status: analyzed
|
||
confidence: high
|
||
created: 2026-10-17
|
||
question: Which Rust crates should render previews (images, PDF, DJVU, EPUB, markdown, media) in a terminal, with what licenses and fallbacks?
|
||
tags: [research, rust, crates, preview, ratatui]
|
||
---
|
||
|
||
# Rust preview stack (October 2026)
|
||
|
||
Versions verified against crates.io metadata on 2026-10-17.
|
||
|
||
## Recommended stack
|
||
|
||
| Concern | Crate | Why | Notes / license |
|
||
|---|---|---|---|
|
||
| TUI | **ratatui 0.30** + **crossterm 0.29** | De-facto standard; 0.30 split into `ratatui-core`/`-widgets` facade; yazi & felix use it | MIT; MSRV 1.88 |
|
||
| Images in TUI | **ratatui-image 11.1** | kitty, sixel, iTerm2, halfblocks + `Picker` protocol/font detection; lives in the ratatui org | MIT |
|
||
| Image decode | **image 0.25** | yazi's choice; jpeg/png/gif/webp/bmp/tiff (+avif feature) | MIT/Apache |
|
||
| Resize | **fast_image_resize 6.1** (SIMD) or `image::thumbnail` (triangle filter, yazi-style) | hot loop | MIT/Apache |
|
||
| Sixel encode | **quantette 0.6** (+ moxcms, palette) | yazi's actual sixel pipeline | MIT |
|
||
| PDF | **pdfium-render 0.9** + pdfium binary | only mature page→image in-process option | pdfium is **Apache-2.0** (b redistribute, ~5 MB); spawn `pdftoppm` as fallback |
|
||
| DJVU | **djvu-rs 0.43** (pure Rust, render→image) | first usable pure-Rust DjVu decoder | **6 months old** — keep `ddjvu` fallback |
|
||
| EPUB | hand-rolled: **zip** + quick-xml/html-to-text | the `epub` crate is **GPL-3.0 — viral** if statically linked | avoid the trap |
|
||
| Markdown | **comrak 0.56** → styled ratatui lines, or **termimad** (ready-made renderer) | termimad = fastest integration (broot uses it) | MIT |
|
||
| Syntax highlight | **syntect 5.3** | yazi's choice; regex Sublime syntaxes, no C deps | tree-sitter = heavier, per-language grammars |
|
||
| Media metadata | **spawn `ffprobe -print_format json`** | no linking pain; what yazi does | ffmpeg-next ties you to system FFmpeg — avoid |
|
||
| Video thumbnail | **spawn `ffmpeg -ss … -vframes 1 -vf scale…`** (+ `attached_pic` cover-art fallback) | yazi's proven recipe | — |
|
||
| Audio (optional in-process) | **symphonia 0.6** | pure-Rust metadata/album art | MPL-2.0 |
|
||
| MIME | **infer 0.22** (magic bytes) + **xdg-mime 0.4** (extension DB) | fast sniffing + correct `text/*` | `new_mime_guess` unmaintained — avoid |
|
||
| FS events | **notify 8.2** | yazi's watcher | CC0 |
|
||
| Fuzzy | **nucleo 0.5** | Helix's matcher, library-first | MPL-2.0 |
|
||
| Config | **serde + toml 1.1** | yazi's set | solid |
|
||
| Errors/logs | **anyhow + thiserror 2.x + tracing** | boring and correct | — |
|
||
| Async | **tokio 1.x** with results marshalled to a single-threaded UI actor | yazi's exact architecture; ecosystem is tokio-first | start threads-only, adopt tokio in Sprint 8 |
|
||
|
||
## Image protocol fallback chain (first match wins)
|
||
|
||
1. **kitty graphics** (unicode-placeholder mode) — kitty ≥0.28, Ghostty ← *our primary target*
|
||
2. **iTerm2 inline** — WezTerm, iTerm2, Warp, VSCode terminal
|
||
3. **sixel** — foot, Konsole 22.04+, Windows Terminal ≥1.22, WezTerm, rio
|
||
4. **ueberzug++ subprocess** — X11 + Wayland (wlroots compositors: sway/hyprland/niri/wayfire);
|
||
the only option for alacritty; not GNOME/KDE compositors
|
||
5. **chafa / halfblocks** — works everywhere incl. SSH and tmux
|
||
6. text: filename + size + mime
|
||
|
||
Terminal facts (Oct 2026): kitty has **no sixel by design**; alacritty rejected both protocols;
|
||
tmux needs `allow-passthrough on` and never passes kitty-old. The daily terminal here is
|
||
**kitty without a multiplexer** → tier 1 covers the primary user; tiers 3–5 cover everyone else.
|
||
|
||
## Thumbnail caching (yazi-proven)
|
||
|
||
Decode once at preview size (max ~600×900, triangle filter) → persist rendered pages/frames to
|
||
a disk cache dir → keep decoded previews in an in-process LRU → preload neighbors in background.
|
||
Re-encoding for a protocol is cheap; re-decoding is not.
|
||
|
||
## Risk notes
|
||
|
||
- GPL traps: `epub` crate (static link), ueberzug++ (fine — spawned), pdftoppm (fine — spawned).
|
||
- pdfium must be shipped as a binary (~5 MB/platform) or static-linked via pdfium-render `static`.
|
||
- djvu-rs is young; config-selectable `ddjvu` fallback required.
|
||
- ratatui 0.30 subcrate split may cause ecosystem churn in 2026 — pin carefully.
|
||
|
||
## Outcome
|
||
Feeds ADR-001, ADR-004 and Sprints 5–8 crate choices.
|
||
|
||
## Sources
|
||
- https://github.com/sxyazi/yazi (adapter/Cargo.tomls, preset plugins pdf.lua/video.lua)
|
||
- https://yazi-rs.github.io/docs/image-preview, /blog/why-is-yazi-fast/
|
||
- crates.io version metadata (ratatui, ratatui-image, image, fast_image_resize, quantette,
|
||
pdfium-render, djvu-rs, epub, comrak, termimad, syntect, symphonia, notify, nucleo, infer, xdg-mime)
|
||
- https://github.com/ajrcarey/pdfium-render; pdfium LICENSE (Apache-2.0)
|
||
- https://www.arewesixelyet.com; https://sw.kovidgoyal.net/kitty/graphics-protocol
|
||
- https://github.com/jstkdng/ueberzugpp; https://github.com/matyushkin/djvu-rs
|