kbp2ass is a program to convert projects from Karaoke Builder Studio (.kbp) to Advanced SubStation Alpha (.ass) format. It maintains wipe timing and styling, and optionally can also preserve display timing, position, and various other attributes from the source file. Here's the current state of tools available making use of the technology:
This is hosted on GitHub. This is currently used within Karaoke Mugen, allowing the direct import of .kbp files into their karaoke management software.
This version may have additional features (though as of 16 Apr 2024, everything is upstreamed). It is also developed on GitHub.
There are also some Windows builds available. They are now being released as GitHub Releases (kbp2ass, kbp2video). Old versions can be found here. To explain some of the file names:
Note that the kbp2video GUI is also open source and the source can be found on GitHub. It now uses kbputils instead of kbp2ass for subtitle conversion.
Current versions below:
This is an all-in-one batch script that Shirakeru created and may be easier to use than the original two-script approach. It allows dragging and dropping a kbp file along with an audio and background file in at the same time, and prompts for some of the options instead of using separate scripts. They are stored on Google Drive. See the README there for detail.
This is still in development, but you can see a preview here.