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MixAudio(clip1 clip, clip2 clip, float clip1_factor, float clip2_factor)
Mixes audio from two clips. A volume for the two clips can be given, but is optional.
Volume is given as a factor, where 0.0 is no audio from the desired channel, and 1.0 is 100% from the desired channel. Default is 0.5/0.5 - if only one factor is given, the other channel will be 1.0-(factor). If factor1 + factor2 is more than 1.0, you risk clipping your signal.
The sample rate of the two clips needs to be the same (use ResampleAudio if necessary). Your clips need also to have the same number of channels (stereo/mono) - use ConvertToMono or MonoToStereo / MergeChannels if necessary.
Example:
# mixes two sources, with one source slightly lower than the other.
video = AviSource("c:\movie.avi")
Soundtrack = WavSource("c:\soundtrack.wav")
Speak = WavSource("c:\speak.wav")
audio = MixAudio(Soundtrack, Speak, 0.75, 0.25) # The Expert may notice that the last 0.25 is actually redundant here.
return AudioDub(video, audio)
