object::afilter property
This feature is available for MPlatform SDK only.
You can use audio filters for FFmpeg to manage audio of your sources (files, network streams, cameras, etc). With the filters, you can control audio volume, filter noise and so on.
The property that you should set to enable an audio filter is "object::afilter" with PropsSet method for your object. For example:
myLive.PropsSet("object::afilter", "volume=2");
If you use several filters in a chain then you should set them in a single value separating by commas:
myLive.PropsSet("object::afilter", "highpass=f=120,acompressor=threshold=0.3:makeup=3:release=50:attack=5:knee=4:ratio=10:detection=peak,alimiter=limit=0.95");
Possible values
|
Filter name |
Filter effect description |
“object::afilter” value |
|---|---|---|
|
acompressor |
Audio compressor. |
acompressor Test chain: acompressor=threshold=0.3:makeup=3:release=50: |
|
acrusher |
Reduce audio bit resolution. |
acrusher Test chain: acrusher=bits=2 |
|
adelay |
Delay one or more audio channels. |
adelay Test chain: adelay=1500|0 Delay first audio channel by 1.5 seconds and leave the second channel (and any other channels that may be present) unchanged.
|
|
aecho |
Add echoing to the audio. |
aecho Test chain: aecho=0.8:0.88:60:0.4 Make it sound as if there are twice as many instruments as are actually playing |
|
aemphasis |
Audio emphasis. |
aemphasis |
|
aeval |
Filter audio signal according to a specified expression. |
aeval Test chain: aeval=val(0)|-val(1) Invert phase of the second channel |
|
afade |
Fade in/out input audio. |
afade |
|
agate |
Audio gate. |
agate |
|
alimiter |
Audio lookahead limiter. |
alimiter |
|
allpass |
Apply a two-pole all-pass filter. |
allpass |
|
amerge |
Merge two or more audio streams into a single multi-channel stream. |
amerge |
|
anequalizer |
Apply high-order audio parametric multi band equalizer. |
anequalizer |
|
aphaser |
Add a phasing effect to the audio. |
aphaser |
|
apulsator |
Audio pulsator. |
apulsator |
|
bandpass |
Apply a two-pole Butterworth band-pass filter. |
bandpass |
|
bandreject |
Apply a two-pole Butterworth band-reject filter. |
bandreject |
|
bass |
Boost or cut lower frequencies. |
bass |
|
biquad |
Apply a biquad IIR filter with the given coefficients. |
biquad |
|
bs2b |
Bauer stereo-to-binaural filter. |
bs2b |
|
chorus |
Add a chorus effect to the audio. |
chorus |
|
compand |
Compress or expand audio dynamic range. |
compand |
|
compensationdelay |
Audio Compensation Delay Line. |
compensationdelay |
|
crossfeed |
Apply headphone crossfeed filter. |
crossfeed |
|
crystalizer |
Simple expand audio dynamic range filter. |
crystalizer |
|
dcshift |
Apply a DC shift to the audio. |
dcshift |
|
earwax |
Widen the stereo image. |
earwax |
|
equalizer |
Apply two-pole peaking equalization (EQ) filter. |
equalizer |
|
extrastereo |
Increase difference between stereo audio channels. |
extrastereo |
|
firequalizer |
Finite Impulse Response Equalizer. |
firequalizer |
|
flanger |
Apply a flanging effect to the audio. |
flanger |
|
has |
Apply Haas Stereo Enhancer. |
haas |
|
highpass |
Apply a high-pass filter with 3dB point frequency. |
highpass |
|
lowpass |
Apply a low-pass filter with 3dB point frequency. |
lowpass |
|
pan |
Remix channels with coefficients (panning). |
pan Test chain: pan=1c|c0=0.9*c0+0.1*c1 |
|
stereotools |
Apply various stereo tools. |
stereotools Test chain: stereotools=mlev=0.015625 |
|
stereowiden |
Apply stereo widening effect. |
stereowiden |
|
treble |
Boost or cut upper frequencies. |
treble Test chain: treble=10 |
|
tremolo |
Apply tremolo effect. |
tremolo |
|
vibrato |
Apply vibrato effect. |
vibrato |
|
volume |
Change input volume. |
volume |