Packages with the tremor use flag

media-libs / sdl2-mixer : Simple Direct Media Layer Mixer Library

enable OGG Vorbis music via libtremor

media-sound / cmus : Ncurses based music player with plugin support for many formats

Use libivorbis from media-libs/tremor instead of media-libs/libvorbis

media-sound / moc : Music On Console - ncurses interface for playing audio files

Build vorbis support using an integer implementation of the vorbis library (media-libs/tremor)

media-sound / snapcast : Synchronous multi-room audio player

Build with TREMOR version of vorbis

media-video / mplayer : Media Player for Linux

Enable internal support for Vorbis

media-video / vlc : Media player and framework with support for most multimedia files and streaming

Enable tremor, a fixed-point version of the Ogg Vorbis decoder