I would strongly encourage you to read the documentation. Even if there is no example, there is a specific description of how filters are defined on the command line.
A filter is represented by a string of the form:
filter_name=arguments(…)
argumentsis a string which contains the parameters used to initialize the filter instance
- A
:-separated list ofkey=valuepairs.- …
So, the equalizer filter takes these (required) arguments:
f– central frequency in Hzwidth_type– for defining the bandwidth, can be one ofh(Hz),q(Q),o(octave) ors(slope).w– the value of the chosen bandwidthg– the gain
Now let's put that all together. For example, you can use this command to attenuate 10 dB at 1000 Hz with a bandwidth of 200 Hz:
ffmpeg -i input.wav -af "equalizer=f=1000:width_type=h:width=200:g=-10" output.wav Or, for equalizing 2 octaves from 440 Hz (i.e., 220–880 Hz), with a gain of 5 dB (beware of clipping!):
ffmpeg -i input.wav -af "equalizer=f=440:width_type=o:width=2:g=5" output.wav And if you want to combine these two, separate them by a ,:
ffmpeg -i input.wav -af "equalizer=f=440:width_type=o:width=2:g=5,equalizer=f=1000:width_type=h:width=200:g=-10" output.wav