Preparing BMS Song for Online Play in Bemuse [new method]

This guide will walk you through the steps of preparing a BMS song to make it playable online in Bemuse.

While players can download a BMS archive and load it in Bemuse, preparing a song for online play has a few extra benefits:

Regular BMS archive played in Bemuse	BMS prepared for online play in Bemuse
Has to be downloaded in order to play	Can be played online without downloading
Displays a generic eyecatch image (※1)	Can display a custom eyecatch image
Displays a generic background image (※1)	Can display a custom background image
BGA is not supported in Bemuse (※1)	Can play a high-definition video file as BGA
No commentary and links in the Information tab	Can add commentary and links to the Information tab
Different songs have different loudness	Loudness level is normalized with ReplayGain
No song preview	Players can hear a preview of the song in Bemuse

※1 — Except for .bmson charts where Bemuse has support for these features.

Outline

This guide will cover:

1. How to prepare a BMS song for playing in Bemuse.
2. How to test it in Bemuse locally.
3. How to test it online in Bemuse.
4. How to publish multiple songs as Music Servers.

What you need

• To prepare a song for online play:

  • The BMS archive to prepare.
  • Latest version of Google Chrome or Microsoft Edge web browser.

• To host a music server:

  • A web hosting provider that supports HTTPS and can be configured to enable CORS.

The song workshop application

Using Google Chrome or Microsoft Edge, go to the Bemuse Song Workshop application at this URL:

https://song-workshop.bemuse.ninja/

We will use this application throughout the rest of this guide.

Warning

Please note that this application can be very buggy and the developer currently does not have the resources to provide support, although Bemuse’s developers also use this app to manage the official server. However if you are a developer, you can find the source code on GitHub. If you managed to fix some issues, pull requests are welcome.

Preparing a song

Extract the archive

First, extract the BMS archive into a folder.

Open the folder in Song Workshop

• In Song Workshop, select Custom song.

  

• Click Choose a song folder and select the extracted folder.

  

• You will see the dashboard.

  

Optimize sound assets

BMS archives typically contains hundreds of sound files. Downloading many small files on the web can be slow. By optimizing sound assets, all sounds will be compressed as .ogg files and then bundled up into .bemuse files.

• Go to the Sound assets tab.

• Click Optimize sound assets.

• Wait until finished. Depending on the song and your internet speed, this may take several minutes.

  

• You will also see the a new subfolder bemuse-data/sound with optimized files.

  

Generate a metadata file

Normally, the BMS song folder must be scanned to search for available chart files (.bms .bme .bml .bmson), and each chart file must be parsed to obtain the metadata. However, it is not practical on the web to scan directories and read each file. Therefore, for online songs Bemuse requires a metadata file which contains information about the song and all its available charts.

• Go to the Charts tab.

• Click on Scan charts.

• After this is finished, you should see a list of charts.

  

• You will also see the a new file in the song folder: bemuse-song.json.

  

Generate a song preview

Generating a song preview allows player to listen to an excerpt of the song in the Music Selection screen.

• Go to Preview tab.

• Select a chart to generate a preview. Usually I pick the medium-difficulty chart.

• Click Render song and wait until finished. This will render the selected chart into a high-quality OGG file. This process will also analyze the song’s loudness and save it to the song’s metadata.

• Listen to the song and choose starting point of the song preview. Song previews are always 30 seconds long.

• Put in the seconds number and then click Create song preview.

• Review the song preview and make appropriate adjustments.

  

• New files will be created: bemuse-data/song.ogg and bemuse-data/preview.mp3

  

Add more song metadata

• Go to the Metadata tab.

• Add the metadata and click Save song metadata to save the metadata in the song folder as bemuse-song.json.

  

• The song description will be saved in README.md.

  

Add image and video files

• Add these files:

  • bemuse-data/eyecatch_image.{jpg,png} — Displayed while loading the song.
  • bemuse-data/back_image.{jpg,png} — Displayed in-game.
  • bemuse-data/bga.{mp4,webm} — Background animation.

  

• Go to the Visuals tab.

• Click on the Scan button.

• You should see the images and video files displayed.

• For video, click on Test Synchronization to check if the video and audio are in sync. If not, click Set video offset and test again.

  

Clean up files

Now, all assets has been optimized and all necessary metadata files are created. We can now clean up the folder to save up space.

• Delete these files:

  • *.ogg *.wav — Keysound files
  • *.png *.bmp *.jpg — BGA files
  • *.wmv *.avi *.mpg — Video files

  In the end, the following files should remain:

  • *.bms *.bme *.bml *.bmson — BMS/bmson chart files
  • bemuse-song.json — Metadata file
  • bemuse-data — Optimized data folder

  

Congratulations!

Now the song has been prepared for online play. The next step is to test your song locally in Bemuse.

Test your song locally

To test your song locally,

• Launch Bemuse.
• Drag the song folder into the Custom BMS dialog.

Bemuse will detect bemuse-song.json in the folder and load the song. You should hear the song preview, see the images, video, and other information.

Upload your song

Now that your song is prepared and tested, it’s time to put it online!

• Upload the song folder to a hosting service.

  

• Obtain the URL to the bemuse-song.json file.

  • For example: https://music4.bemuse.ninja/songs/[frums]credits/bemuse-song.json

Test your song online

Now that your song is online, you can test it!

• Go to

  https://bemuse.ninja/?server=<url/to/bemuse-song.json>
  

  • For example: https://bemuse.ninja/?server=https://music4.bemuse.ninja/songs/[frums]credits/bemuse-song.json

  • (Alternatively, you can launch Bemuse normally and then paste the URL into the Custom BMS dialog.)

If you can play the song, then congratulations! Your song has been prepared for online play and is now online.

Create a music server file to publish multiple songs

So far, you have created a “single-song server” which lets you select one song. But what if you want to publish multiple songs for people to play at the same place? In this case you would create a music server file.

• Go to the Bemuse Song Workshop app.

• Select Server Manager.

• Click Create a new server file.

• Create an empty directory for the server and save the index.json file there.

• Paste in the URLs of bemuse-song.json file.

• Click Add. The URL should be added to the list.

• Click Update data.

• Check the results.

  

Upload your music server

• Upload the index.json file to a hosting service.

  

• Obtain the URL to the index.json file.

  • This is your Server URL.
  • You can remove the /index.json part as Bemuse will add it automatically.
  • For example, my server is at https://flicknote.bemuse.ninja/index.json

Test and share your music server

Now that your music server is online, you can try it in Bemuse and share it with your friends!

• Go to https://bemuse.ninja/?server=<Server URL>
  

  • For example, https://bemuse.ninja/?server=https://flicknote.bemuse.ninja