booru-viewer/README.md

booru-viewer

Local desktop app for browsing, searching, and saving images from booru-style imageboards.

Qt6 GUI, cross-platform (Linux + Windows), fully themeable.

If you find this useful, consider buying me a coffee:

Screenshots

Windows 11 — Light Theme

Windows 11 — Dark Theme (auto-detected)

Windows 10 — Light Theme

Windows 10 — Dark Theme (auto-detected)

Linux — Styled via system Qt6 theme

Supports custom styling via custom.qss — see Theming.

Features

Browsing

• Supports Danbooru, Gelbooru, Moebooru, and e621
• Auto-detect site API type — just paste the URL
• Tag search with autocomplete, history dropdown, and saved searches
• Rating and score filtering (server-side score:>=N)
• Media type filter — dropdown: All / Animated / Video / GIF / Audio
• Blacklisted tags and posts (client-side filtering with backfill)
• Thumbnail grid with keyboard navigation
• Infinite scroll — optional, auto-loads more posts at bottom
• Start from page — jump to any page number on search
• Page cache — prev/next loads from memory, no duplicates
• Copy File to Clipboard — Ctrl+C, works for images and videos

Preview

• Image viewer with zoom (scroll wheel), pan (drag), and reset (middle click)
• GIF animation, Pixiv ugoira auto-conversion (zip to animated GIF)
• Animated PNG/WebP auto-conversion to GIF
• Video playback via mpv (MP4, WebM, MKV) with play/pause, seek, volume, mute, and seamless looping
• Info panel with post details, date, clickable tags, and filetype
• Preview toolbar — Bookmark, Save, BL Tag, BL Post, and Popout buttons above the preview panel

Popout Viewer

• Right-click preview → "Popout" or click the Popout button in the preview toolbar
• Arrow keys / h/j/k/l navigate posts (including during video playback)
• , / . seek 3 seconds in videos, Space toggles play/pause
• Floating overlay UI — toolbar and video controls auto-hide after 2 seconds, reappear on mouse move
• F11 toggles fullscreen/windowed, Ctrl+H hides all UI, Ctrl+P privacy screen
• Window auto-sizes to content aspect ratio; state persisted across sessions
• Hyprland: keep_aspect_ratio prop locks window to content proportions
• Bidirectional sync — clicking posts in the main grid updates the popout
• Video position and player state synced between preview and popout

Bookmarks & Library

• Bookmark posts, organize into folders
• Three-tab layout: Browse, Bookmarks, and Library
• Save to library (unsorted or per-folder), drag-and-drop thumbnails as files
• Multi-select (Ctrl/Shift+Click, Ctrl+A) with bulk actions
• Bulk context menus in both Browse and Bookmarks tabs
• Unsave from Library available in grid, preview, and popout (only shown when post is saved)
• Import/export bookmarks as JSON

Library

• Dedicated tab for browsing saved files on disk
• Folder sidebar with configurable library directory
• Sort by date, name, or size
• Video thumbnail generation (ffmpeg if available, placeholder fallback)
• Unreachable directory detection

Search

• Inline history dropdown inside the search bar
• Saved searches with management dialog
• Click empty search bar to open history
• Session cache mode clears history on exit (keeps saved searches)

Install

Windows

Download booru-viewer-setup.exe from Releases and run the installer. It installs to AppData with Start Menu and optional desktop shortcuts. To update, just run the new installer over the old one — your data in %APPDATA%\booru-viewer\ is preserved.

Windows 10 dark mode is automatically detected and applied.

Linux

Requires Python 3.11+ and pip. Most distros ship Python but you may need to install pip and the Qt6 system libraries.

Arch / CachyOS:

sudo pacman -S python python-pip qt6-base mpv ffmpeg

Ubuntu / Debian (24.04+):

sudo apt install python3 python3-pip python3-venv mpv libmpv-dev ffmpeg

Fedora:

sudo dnf install python3 python3-pip qt6-qtbase mpv mpv-libs-devel ffmpeg

Then clone and install:

git clone https://git.pax.moe/pax/booru-viewer.git
cd booru-viewer
python3 -m venv .venv
source .venv/bin/activate
pip install -e .

Run it:

booru-viewer

Or without installing: python3 -m booru_viewer.main_gui

Desktop entry: To add booru-viewer to your app launcher, create ~/.local/share/applications/booru-viewer.desktop:

[Desktop Entry]
Name=booru-viewer
Exec=/path/to/booru-viewer/.venv/bin/booru-viewer
Icon=/path/to/booru-viewer/icon.png
Type=Application
Categories=Graphics;

Dependencies

• Python 3.11+
• PySide6 (Qt6)
• httpx
• Pillow
• python-mpv
• mpv (system package on Linux, bundled DLL on Windows)

Keybinds

Grid

Key	Action
Arrow keys / h/j/k/l	Navigate grid
Ctrl+A	Select all
Ctrl+Click / Shift+Click	Multi-select
Home / End	Jump to first / last
Scroll tilt left / right	Previous / next page
Ctrl+C	Copy file to clipboard
Right click	Context menu

Preview

Key	Action
Scroll wheel	Zoom
Middle click / 0	Reset view
Arrow keys / h/j/k/l	Navigate posts
, / .	Seek 3s back / forward (video)
Space	Play / pause (video, hover to activate)
Right click	Context menu (bookmark, save, popout)

Popout

Key	Action
Arrow keys / h/j/k/l	Navigate posts
, / .	Seek 3s (video)
Space	Play / pause (video)
Scroll wheel	Volume up / down (video)
F11	Toggle fullscreen / windowed
Ctrl+H	Hide / show UI
Ctrl+P	Privacy screen
Escape / Q	Close popout

Global

Key	Action
Ctrl+P	Privacy screen
F11	Toggle fullscreen

Adding Sites

File > Manage Sites. Enter a URL, click Auto-Detect, and save.

API credentials are optional — needed for Gelbooru and rate-limited sites.

Tested Sites

• danbooru.donmai.us
• gelbooru.com
• rule34.xxx
• safebooru.donmai.us
• safebooru.org
• e621.net

Theming

The app uses your OS native theme by default. To customize, copy a .qss file from the themes/ folder to your data directory as custom.qss:

• Linux: ~/.local/share/booru-viewer/custom.qss
• Windows: %APPDATA%\booru-viewer\custom.qss

A template is also available in Settings > Theme > Create from Template.

Included Themes

Settings

• General — page size, thumbnail size, default site, default rating/score, prefetch mode (Off / Nearby / Aggressive), infinite scroll, popout monitor, file dialog platform
• Cache — max cache size, max thumbnail cache, auto-evict, clear cache on exit (session-only mode)
• Blacklist — tag blacklist with toggle, post URL blacklist
• Paths — data directory, cache, database, configurable library directory
• Theme — custom.qss editor, template generator, CSS guide
• Network — connection log showing all hosts contacted this session

Data Locations

	Linux	Windows
Database	~/.local/share/booru-viewer/booru.db	%APPDATA%\booru-viewer\booru.db
Cache	~/.local/share/booru-viewer/cache/	%APPDATA%\booru-viewer\cache\
Library	~/.local/share/booru-viewer/saved/	%APPDATA%\booru-viewer\saved\
Theme	~/.local/share/booru-viewer/custom.qss	%APPDATA%\booru-viewer\custom.qss

Privacy

booru-viewer makes no connections except to the booru sites you configure. There is no telemetry, analytics, update checking, or phoning home. All data stays local on your machine.

Every outgoing request is logged in Settings > Network so you can verify this yourself — you will only see requests to the booru API endpoints and CDNs you chose to connect to.

License

MIT