Audio Mixer: Technical Specs
Audio Mixer DirectShow specs
Audio mixer is a standard DirectShow filter.
Number of input pins = 2 for stereo and mono modes and from 1 to 64 for custom mode (new pin will be added after connection of all
free input pins).
Number of output pins = 1 for stereo and mono modes and from 1 to 64 for custom mode (new pin will be added after connection of all
free output pins).
Number of bits per mono audio sample for any input or output: from 8 to 32
Input/output media type:
majortype:
MEDIATYPE_Audio
subtype:
MEDIASUBTYPE_PCM
formattype:
FORMAT_WaveFormatEx
cbFormat, pbFormat:
WAVEFORMATEX struct (wFormatTag = WAVE_FORMAT_PCM) for nChannels = 1 or 2 only
WAVEFORMATEXTENSIBLE struct (Format.wFormatTag = WAVE_FORMAT_EXTENSIBLE)
Parameters of format:
WAVEFORMATEX::nSamplesPerSec: the same for all inputs and outputs.
WAVEFORMATEX::nChannels from 1 to 32. Can be different for different input/output pins.
WAVEFORMATEX::wBitsPerSample: from 8 to 32. Can be different for different input/output pins.
Any channel(s) of any input pin(s) can be mixed with any other channel(s) of same or other input pin(s). Mixing coefficients can be changed in play time
also (without graph stop).
Notes:
- All input frequencies should be identical (resampling not implemented in current version).
- After start of graph the media type of output pins cannot be changed.