Convert comments from Niconico/AcFun/bilibili to ASS format
Switch branches/tags
Nothing to show
Clone or download
m13253 Merge pull request #41 from j16180339887/master
Force to override symbolic link
Latest commit 3dd20e4 Jul 30, 2017


What is it?

Danmaku2ASS converts comments from Niconico/Acfun/Bilibili to ASS format so that you can play it with any media player supporting ASS subtitle.

This software is free software released under GPL 3 license. There is no warranty to the extent permitted by law.

How to use it?

First, you will have to get the XML or JSON file from Niconico/Acfun/Bilibili, many software can help you get it. For example, you-get and nicovideo-dl.

Then, execute danmaku2ass. You can see further instructions below.


You may install danmaku2ass with the Makefile provided.

make install

PREFIX= is accepted by make install for specifying installation prefix.

A PKGBUILD is also provided.

Example usage

./danmaku2ass -o foo.ass -s 1920x1080 -fn "MS PGothic" -fs 48 -a 0.8 -dm 5 -ds 5 foo.xml

Name the output file with same basename but different extension (.ass) as the video. Put them into the same directory and most media players will automatically load them. For MPlayer, you will have to specify -ass option.

Make sure that the width/height ratio passed to danmaku2ass matches the one of your original video, or text deformation may be experienced.

You can also pass multiple XML/JSON files and they will be merged into one ASS file. This is useful when watching danmakus from different website at the same time.


5 Centimeters Per Second with Danmaku2ASS

Video: 5 Centimeters Per Second


Players for a specific site

If you prefer to watch videos on a specific site listed below with a media player, you can check these projects, which usually provide online streaming features:

  • Bilibili: BiliDan, (MPV Player, FFmpeg, Linux, OS X, (unstable on) Windows), officially supported by Danmaku2ASS contributer
  • Bilibili: BiliGui, (MPV Player, Ruby, Qt4, FFmpeg, Linux)
  • Bilibili: Biligrab, (Aria2, Python2, FFmpeg, OS X, (unstable on) Linux)
  • Bilibili: MoonPlayer, (MPlayer, Qt4, Linux, Windows)
  • Tudou Doupao, Acfun, Bilibili: Yatto, (MPV Player, FFmpeg, Linux)

Please submit your work if you have made a better one!

Command line reference

usage: [-h] [-f FORMAT] [-o OUTPUT] -s WIDTHxHEIGHT [-fn FONT]
                      [-fs SIZE] [-a ALPHA] [-dm SECONDS] [-ds SECONDS]
                      [-fl FILTER] [-p HEIGHT] [-r]
                      FILE [FILE ...]

positional arguments:
  FILE                  Comment file to be processed

optional arguments:
  -h, --help            show this help message and exit
  -f FORMAT, --format FORMAT
                        Format of input file (autodetect|Bilibili|Tudou2|MioMi
                        o|Acfun|Niconico|Tudou) [default: autodetect]
  -o OUTPUT, --output OUTPUT
                        Output file
                        Stage size in pixels
  -fn FONT, --font FONT
                        Specify font face [default: sans-serif]
  -fs SIZE, --fontsize SIZE
                        Default font size [default: 25]
  -a ALPHA, --alpha ALPHA
                        Text opacity
  -dm SECONDS, --duration-marquee SECONDS
                        Duration of scrolling comment display [default: 5]
  -ds SECONDS, --duration-still SECONDS
                        Duration of still comment display [default: 5]
  -fl FILTER, --filter FILTER
                        Regular expression to filter comments
  -p HEIGHT, --protect HEIGHT
                        Reserve blank on the bottom of the stage
  -r, --reduce          Reduce the amount of comments if stage is full


The text is moving laggy. / The text is slightly blurred.

Most ASS renderers render ASS subtitles at the same resolution as the video. This is probably because the video is at low resolution or framerate.

If you use MPlayer, you can add options similar to -vf scale=1920:1080 (change the values as you wish).`

I would like to render the danmakus into the video.

Use ffmpeg:

ffmpeg -i foo.flv -vf ass=foo.ass -vcodec libx264 -acodec copy foo-with-danmaku.flv

Change the parameters as you like.

Danmaku2ASS gave me some warnings of 'Invalid comment'.

This is probably because of comment styles that are not recognized by Danmaku2ASS. This is mostly normal. However, if you think that Danmaku2ASS missed some important things, please feel free to submit an issue.

Is there a GUI?

Currently no. But there will soon be one made of Gtk+ 3. If you would like to help me, please contact with me.


Any contribution is welcome. Any donation is welcome as well.