Mizune shows the subtitle line being spoken next to the video. Click a word in it to look it up, go back a line to hear it again, and send words to Anki with the sentence and its audio.
Mizune (水音, "the sound of water") is the girl in the icon. Before 1.0 the app was called Immersion Player.
- Lookups. Click a word or drag across a phrase. Mizune finds the longest word at that point and undoes the conjugation, so 食べさせられなかった finds 食べる and shows the steps. JMdict is built in. Jitendex, JPDB frequencies, pitch accent and any other Yomitan dictionary can be added.
- Line by line. Go back or forward a line, or replay the current one. The video can also pause at the end of every line.
- Peek. Hold i, or hold the line on Android, to see the line in a language you know: English or any of eighteen others. It can also be turned off.
- Anki cards. Press a, or tap + on Android, to add the word with its sentence, the line's audio, a short clip or a still, the reading as furigana and its pitch accent. Works with any note type.
- Subtitles. Files next to the video or tracks inside it: SRT, ASS and WebVTT, plus Blu-ray picture subtitles, which are read with OCR.
- Library. Choose the folder your shows are in. Each folder becomes a series, episodes sort in order, and Mizune remembers where you stopped and offers the next episode.
- Themes. Jade, Sakura, Nord, Paper, Adwaita, Breeze and OLED Black, in light and dark, following the system or not. Desktop has Anime4K upscaling built in.
- Updates. New versions download in the background and are checked against a signature before they install.
The first launch takes you through setup: theme, peek language, video folder, dictionaries and Anki.
 |
 |
| The line over the video, with the panel put away (s) | The library |
 |
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| Choosing dictionaries during setup | The dark Jade theme |
Download from the latest release.
- macOS (Apple Silicon, macOS 15.8.1 or newer): open the
.dmgand drag Mizune to Applications. It isn't notarised yet, so the first time, right-click it and choose Open, or runxattr -dr com.apple.quarantine "/Applications/Mizune.app". - Windows (x64, Windows 10 or newer): run the
.msi. It installs for your user only, so it doesn't need an administrator. It isn't signed yet, so if SmartScreen stops it, choose More info, then Run anyway. - Linux (x64): the
.AppImageruns on distributions from about 2022 on (Ubuntu 22.04, Debian 12, Fedora 36). Make it executable and run it. Ubuntu 24.04, Debian 13 and newer can use the.debinstead, which uses the system's libmpv:sudo apt install ./Mizune-*-linux-x64.deb. - Android (arm64, Android 11 or newer): install the
.apk.
macOS and Android install updates themselves. Windows and Linux say when there's a new version and link to it.
Found a bug, or want something changed? Open an issue.
Once a day the app sends Google Analytics a random ID made for your install, your platform and
its version, and the app's version. Nothing about what you watch, look up or add to Anki, and
no account. It uses the Measurement Protocol, not Google's SDK, and on desktop it only starts
after setup. Turn it off during setup or under Settings › General › Privacy (Settings › Privacy
on Android). The code is in UsageStats.
These are the defaults. Every key can be changed under Settings › Keyboard, and the key map exported as a file to keep or share, or imported from one.
| Key | Does |
|---|---|
| Space | play / pause |
| h / l | previous / next line, and keep playing |
| j / k | previous / next line, and stop at its end |
| ; | replay this line and stop at its end |
| hold i, or hold the line | show the line in the peek language |
| y / o | 5 s back / forward |
| n / m | subtitles 0.1 s earlier / later |
| u | stop at the end of every line, on or off |
| s | hide or show the panel; when it's hidden, the line goes over the video |
| z, or ⌘ + scroll | fill the area, or fit the whole picture |
| f, F11, or double-click | full screen |
| drag the video | move the window |
| ⌘ (Ctrl) + 1–6 | Anime4K modes A, B, C, A+A, B+B, C+A |
| ⌘ (Ctrl) + 0 | Anime4K off |
| Esc | close a lookup, leave full screen, then back to the library |
| click / drag a word | look it up |
| a | add the looked-up word to Anki |
| Return | at the end of a video, play the next one |
Going back a line from a stop replays that line first. While paused, l and k start playing instead of skipping ahead. h and l also skip the stops that u turns on, until you next press j, k or ;.
The app shows these once, on first run.
| Where | Gesture | Does |
|---|---|---|
| Video | tap | play / pause |
| Video | double-tap the left or right edge | 5 s back / forward; keep tapping to go further |
| Video (panel on screen) | drag sideways | scrub; move up or down while dragging to scrub faster |
| Video | pinch | fill the area, or fit the whole picture |
| Video (paused) | tap or drag the bottom line | seek |
| Video (panel off screen) | swipe sideways | previous / next line |
| Video (panel off screen) | double-tap the middle | stop at the end of every line, on or off |
| Video (panel off screen) | hold | show the line in the peek language |
| Line | tap a word | look it up |
| Line | drag across the text | look up the selection |
| Line | hold | show the line in the peek language |
| Panel | swipe sideways | previous / next line |
| Panel | tap | play / pause |
| Panel | double-tap | stop at the end of every line, on or off |
| Divider | drag | resize the video and the panel; in landscape, drag it off the edge to watch with the line over the video |
| Shoulder triggers | press | previous / next line on RedMagic phones (details) |
- Picture subtitles can only be read in English and Japanese. Other peek languages need text subtitles.
- Subtitle files next to a video aren't found when the video is opened from another app.
- Lookups only undo Japanese conjugation.
- Android: arm64 and phone layouts only.
- Desktop: Apple Silicon Macs, and x64 Windows and Linux. OpenGL on Windows and Linux has only been tested without a real GPU, where the app uses software rendering, and Anime4K needs OpenGL.
Bug reports and ideas are welcome as issues. Small fixes can go straight to a pull request; for anything bigger, open an issue first so we can agree on it. CONTRIBUTING.md has the details.
Mizune is written with the help of AI tools. Every change is read line by line and tested by hand before it's merged. Contributions written with AI tools are welcome too, and are reviewed the same way as any other.
Building, testing and releasing are in docs/development.md. How the dictionaries, Anki cards, playback and updates work is in docs/how-it-works.md.
Mizune's code is under the Mozilla Public License 2.0. You can use, change, sell and redistribute it, and combine it with code under other licences. Changed files have to stay under MPL-2.0 with their source available. Releases up to 0.4 were GPL-3.0-or-later and stay so.
The mpv and FFmpeg in every build are LGPL builds without their GPL parts. The bundled libraries, dictionaries and shaders, and their licences, are listed in THIRD-PARTY.md.
The desktop screenshots show Blender Foundation open movies under Creative Commons Attribution: Sintel (CC BY 3.0, with its official Japanese subtitles), Big Buck Bunny (CC BY 3.0), Elephants Dream (CC BY 2.5), Tears of Steel (CC BY 3.0) and Caminandes: Gran Dillama (CC BY), all © Blender Foundation. The dictionary entries in them are from Jitendex (CC BY-SA 4.0) and JMdict, with JPDB frequencies. The Android recording shows Build your first WebAuthn app by Eiji Kitamura for Chrome for Developers (CC BY 3.0), with its own Japanese and English subtitles.