BASS_ATTRIB_MIDI_SPEED attribute

Tempo modification.

BASS_ChannelSetAttribute(
    DWORD handle,
    BASS_ATTRIB_MIDI_SPEED,
    float speed
);

Parameters

handle	The MIDI stream handle.
speed	The tempo change... 1.0 = normal, below 1.0 = slower, above 1.0 = faster. The final tempo is the product of this value and the original tempo.

Changing the tempo affects the stream length, and the BASS_ChannelGetLength byte value will no longer be valid. Seeking is not affected.

Changes can be made at any time, but the effect of changes during playback may not be heard instantaneously due to buffering.