Embedded filters and gain

Native filters and master volumeCopy Anchor Link

Both PlaybackSession and DiscordSession expose the core's raw FFmpeg audio filtergraph and an independent master gain. No named music presets are part of @remedia/node.

await voice.filters.set('bass=gain=8,volume=0.8');
await voice.setVolume(0.75);

await voice.filters.set('tremolo=f=5:d=0.6'); // replaces the previous graph live
await voice.filters.clear();
console.log(voice.filters.graph, voice.volume); // null, 0.75

Replace a graph during playbackCopy Anchor Link

Set filters before play() or connect(), while playing, or while paused. A replacement is validated before it becomes active at the next decoded PCM boundary. Invalid graphs reject and leave the current graph in place.

Already submitted audio stays accepted, while delayed output held by the old graph is discarded. A live filter change keeps the source decoder and voice connection open. If natural EOF wins before the next boundary, the setting applies to the next source on that session. A seek that loses an EOF race rejects.

Pass a raw audio expression such as bass=gain=6, without command-line flags. Empty strings reject. Use filters.clear() to disable the graph. Expressions need one effective audio input and output. FFmpeg filters can access files or URLs, so accept graphs only from trusted applications.

For partial Opus frames, seek flushes, and exact worker ordering, see Rust filter replacement.

Gain and clippingCopy Anchor Link

volume is a normalized linear gain from 0 through 2. The default is 1. setVolume(0) mutes without stopping playback, setVolume(1) is unity, and values above one may clip. Samples are clamped to [-1, 1]. This is not limiting or loudness normalization. Volume is applied after the graph and is preserved when filters change or tracks are replaced on the same session. Each session has independent settings, and disposal releases them.

Source and output timeCopy Anchor Link

Tempo and buffering filters change the relationship between original-source position and submitted PCM. Seeking stays relative to the original source. Use the position fields and accuracy metadata when displaying progress. Each session retains its graph and gain across tracks and transport recovery.