We're need a DirectShow filter that implements audio mixer. The filter should have up to 8 input pins and one output pin and should work with PCM / IEEE audio data. Filter interface needs to have amplification controls for the inputs and for output (use floating point values). Seeking must work correctly in graph edit tool. Custom output format can be set.
Filter with full source code required then all work is done. Binary version for testing.
Any 3rd-party libraries usage must be discussed. No GPL code.
Visual C++ 2010, x86 and x64 (no MFC), Windows XP and later.
We have already done a task similar to this one and thus we can provide you with exactly the tool you need. Using Visual C++ 2010 and DirectX to access the devices, we have mixed two PCM audio streams producing a combined output. We would have to add just the amplification controls to let you adjust the input channels and direct the output to the device you want. No external libraries are needed for that, we have our own routines. Also we don't use MFC, we call always the WinAPI entry points directly. The solution would work on any Windows version from XP up.
Regards
The Bramfeld Team