Mozc

From the project's
home page
:
Mozc
is a Japanese
input method
editor (IME) designed for multi-platform such as Android OS, Apple OS X, Chromium OS, GNU/Linux and Microsoft Windows. This OpenSource project originates from
Google Japanese Input
.
The differences between Mozc and Google Japanese Input are described in detail at the project's
About Branding
page, but in short, Mozc's open-source code does not include Google's extensive word conversion tables (so called "dictionaries"), so its conversion quality is not equivalent to that of Google's branded product. This can be mostly mitigated with custom dictionaries though (see below).
Installation
Split vs. integrated packages
As an IME, Mozc has two distinct parts: a
server
, which does all the work of the conversion, and a set of
modules
which allow the server to communicate with the system's
input method framework
and output the result on the screen. A separate module is required for each of
IBus
,
Fcitx5
,
Fcitx
and
Emacs
.
Some Mozc packages contain only the IMF-specific modules and
split
the server into a separate
mozc
AUR
package; this allows for the different modules to be installed side by side, independently from the server itself (which can be useful in a multi-user setup where different users use different IMFs, or when using Emacs).
Other Mozc packages forego this split and instead
integrate
the server together with the modules. This does have its advantages, but one very notable disadvantage is that it makes it impossible to install additional modules due to file conflicts (because more than one package are competing to provide the server's files).
If for any reason you will be needing more than one IMF module installed at the same time, the solution is to either build the non-split packages yourself and manually resolve the file conflicts, or to only choose from among the packages that split the server from the modules.
The UT Dictionary
As already mentioned, Mozc's conversion quality is not quite as good as that of Google Japanese Input because it does not include Google's extensive word conversion tables (so called "dictionaries"). A solution exists for that in the form of the
UT dictionary
, which is a third-party dictionary that enhances Mozc's conversion quality and brings it closer to Google Japanese Input. It achieves that by including thousands of additional words aggregated from several popular online sources (based on page rankings from Google, Yahoo and Wikipedia) and also by integrating a variety of other specialized sources such as the
NEologd dictionary
, which in the words of its creator contains
"neologisms (new words), which are extracted from many language resources on the Web"
.
Tip
Use of the UT dictionary is optional but highly recommended.
Summary
Install
one or more of
fcitx5-mozc-ut
AUR
,
fcitx-mozc-ut
AUR
,
ibus-mozc
AUR
and
emacs-mozc
AUR
.
When you are asked which flavor of Mozc you wish to use, select either
mozc
AUR
for the vanilla Mozc or
mozc-ut
AUR
for the UT-enhanced Mozc.
Tip
If you wish to use the
integrated packages
you can instead install
fcitx5-mozc
or
fcitx-mozc
AUR
(both of them are based on the vanilla Mozc).
Note
Once Mozc is installed, you may need to restart X or your input method framework before you can use it.
Configuration
IBus
This article or section needs language, wiki syntax or style improvements. See
Help:Style
for reference.
Reason:
Mostly in
Template:Tip
, are they really
useful but ignorable
in the context of this section? (Discuss in
Talk:Mozc
)
See
IBus
for more information.
Tip
When used with IBus, by default Mozc will launch in Direct (Eisu) input mode, which can be problematic on keyboards that lack the Eisu key. To change this behavior and make Mozc launch in Hiragana input mode instead, edit
~/.config/mozc/ibus_config.textproto
and append the following line:
~/.config/mozc/ibus_config.textproto
...
}
active_on_launch: True
If that doesn't work:
Check that
~/.mozc/ibus_config.textproto
does not exist. If it does (for example because Mozc was upgraded from an older installation), it will take precedence over
~/.config/mozc/ibus_config.textproto
.
Run the
ibus write-cache; ibus restart
command to restart IBus.
More information is available in the
Mozc documentation
.
Tip
On
GNOME
, IBus is integrated with the System Settings so there is no need to run a separate app. Simply go to
System Settings > Keyboard
and add the Mozc layout there. You can then disregard the following instructions.
Open the IBus configuration tool by running:
$ ibus-setup
In the
Input Method
tab, click on
Add
, and then search for and add the Mozc layout.
You can switch to the new Mozc layout with
Alt+Shift_L
(as per the IBus default).
Fcitx5
See
Fcitx5
for more information.
Tip
On
KDE
, Fcitx5 is integrated with the System Settings so there is no need to run a separate app. Simply go to
System Settings > Regional Settings > Input Method
. If this option is missing, install the
fcitx5-configtool
package.
Open the Fcitx5 configuration tool by running:
$ fcitx5-configtool
In the
Input Method
tab, add Mozc in the
Add Input Method
menu. You can set the keyboard shortcut to switch between layouts in
Configure global options
.
This is different to the normal KDE layout switcher, so one could switch between different layouts mapped to Japanese by Mozc.
Similar to Ibus’
Use system keyboard layout
, you can select the layout for Mozc to the left of the remove button. This selects the layout to use
before
Mozc, so one can use custom layouts mapped correctly to Mozc.
Emacs
You can use mozc.el (mozc-mode) to input Japanese via LEIM (Library of Emacs Input Method). To use mozc-mode, write the following into your
.emacs.d/init.el
or some other file for Emacs customizing:
(require 'mozc)  ; or (load-file "/path/to/mozc.el")
(setq default-input-method "japanese-mozc")
mozc.el provides "overlay" mode in the styles of showing candidates (from mozc r77) which shows a candidate window in box style close to the point. If you want to use it by default, add the following:
(setq mozc-candidate-style 'overlay)
C-\
(
toggle-input-method
) enables and disables use of mozc-mode.
Disabling XIM
When you are using input method on your desktop and assigning activation/deactivation of input method to C-SPC, you will be not able to use C-SPC/C-@ as set-mark-command on Emacs. To avoid this problem, add the following into your
~/.Xresources
or
~/.Xdefaults
. xim will be disabled on Emacs.
Emacs*UseXIM: false
Tips and tricks
Confirming Mozc version which you are using now
Type "ばーじょん" ("version") and convert it while activating Mozc. The version number of Mozc will be shown in the candidate list like follows:
ばーじょん
バージョン
ヴァージョン
ばーじょん
Mozc-1.6.1187.102
⇐ Current version of Mozc
...
Launching Mozc tools from command line
The followings are commands to launch Mozc tools:
Mozc Settings:
/usr/lib/mozc/mozc_tool --mode=config_dialog
Mozc Dictionary Tool:
/usr/lib/mozc/mozc_tool --mode=dictionary_tool
Mozc Word Register:
/usr/lib/mozc/mozc_tool --mode=word_register_dialog
Use CapsLock as Eisu_toggle key on ASCII layout keyboard
In all of the preset keymap styles of Mozc, the command
Toggle alphanumeric mode
on
Composition
mode is assigned to the
Eisu
(Eisu_toggle),
Hiragana/Katakana
or
Muhenkan
key, but the ASCII keyboard has none of them.
One solution for it is to use Caps Lock key as Eisu_toggle (Mozc does not recognize the Caps Lock key as of r124). The following is a way to assign Eisu_toggle to
Caps Lock
(without any modifier keys) and Caps_Lock to
Shift+CapsLock
, as on the OADG keyboard layout.
Warning
This will affect all applications.
Edit
~/.Xmodmap
as follows:
keycode 66 = Eisu_toggle Caps_Lock
clear Lock
Then, restart X or run
xmodmap
to apply the changes immediately:
$ xmodmap ~/.Xmodmap
Use underlying Japanese keymap on Non-English/Non-Japanese systems
If you are primarily using a Non-English or Non-Japanese system with a keyboard layout different than QWERTY (e.g. German) and only want to use Japanese as a secondary input language, the key mapping might be based on this
main keyboard language
. This might be odd, especially if migrating from Windows or MacOS or directly from a Japanese computer.
To change the underlying keyboard layout on Ibus, change the default keymap in
~/.config/mozc/ibus_config.textproto
by setting the
layout
key to Japanese (or some other keyboard with QWERTY):
~/.config/mozc/ibus_config.textproto
engines {
...
  layout : "jp"
...
}
Troubleshooting
Building Mozc fails (process is killed)
If the build process fails with an error message like the following:
...
/bin/sh: line 1:  xxxx killed
...
make: *** [xxx/xxx...] error 137
...
Make sure you have not run out of memory.
New version of Mozc does not appear though I upgraded Mozc and restarted X or Input Method Framework (not rebooted)
The old version of Mozc may be still on your memory. Try to kill the existing
mozc_server
process:
$ killall mozc_server
mozc_server becomes defunct
Mozc cannot run in root. Start X in normal user.
mozc_emacs_helper not found in emacs
When installing mozc.el you need to install a helper program called
mozc_emacs_helper
.
You need to install
emacs-mozc
AUR
for this helper program.
mozc tool(s) does not launch
It is also possible to launch Mozc tools with log sent directly to console, which is useful for debugging. To enable this, simply append
--logtostderr
like this for example:
$ /usr/lib/mozc/mozc_tool --mode=config_dialog --logtostderr
See also
Suggestion window is blindingly white in dark mode
Use the following
environment variable
:
MOZC_IBUS_CANDIDATE_WINDOW=ibus