diff --git a/DOCS/man/af.rst b/DOCS/man/af.rst index 98f9a9597a..3a75c0822d 100644 --- a/DOCS/man/af.rst +++ b/DOCS/man/af.rst @@ -226,10 +226,7 @@ Available filters are: using the standard ``speed`` property, not ``af-command``. ``multiply-pitch `` - Multiply the current value of ```` dynamically. For - example: 0.5 to go down by an octave, 1.5 to go up by a perfect fifth. - If you want to go up or down by semi-tones, use 1.059463094352953 and - 0.9438743126816935 + Multiply the current value of ```` dynamically. ``lavfi=graph`` Filter audio using FFmpeg's libavfilter. diff --git a/DOCS/man/options.rst b/DOCS/man/options.rst index 9192b93cb3..ae4662c95d 100644 --- a/DOCS/man/options.rst +++ b/DOCS/man/options.rst @@ -242,6 +242,25 @@ Playback Control affect playback speed. Playing with an altered pitch automatically inserts the ``scaletempo2`` audio filter. + In a standard 12-tone scale system, octaves are separated by a factor of 2 + whereas semitones are represented by a factor of 2^(1/12). This means + pitches can easily be shifted up or down with a simple multiplier. + + .. admonition:: Examples + + ``--pitch=2`` + Shifts the pitch up a full octave. + ``--pitch=0.5`` + Shifts the pitch down an octave. + ``--pitch=1.498307`` (2^(7/12)) + Shifts the pitch up a perfect fifth. + ``--pitch=0.667420`` (2^(-7/12)) + Shifts the pitch down a perfect fifth. + ``--pitch=1.059463`` (2^(1/12)) + Shifts the pitch up a semitone. + ``--pitch=0.943874`` (2^(-1/12)) + Shifts the pitch down a semitone. + ``--pause`` Start the player in paused state.