Having separate volume control over multiple media sessions (Media Foundation)

[malibor]

Hello, I have a class that loads an audio file (wav/mp3) and play them, the class has IMFSimpleAudioVolume member initialized with MFGetSErvice for example:

IMFSimpleAudioVolume* pVolume;

MFGetService(pSink, MR_POLICY_VOLUME_SERVICE, IID_PPV_ARGS(&pVolume));

I won't post entry class here since it's huge, but basically the class is a media session that plays a single file.

I create multiple objects of this class, each object representing an audio file that plays in same time as other files, the problem is that when I change master volume in one object (for one file) via IMFSimpleAudioVolume::SetMasterVolume the master volume changes the volume of other objects (files) too!

I need to have each object their own volume level independent of each other, so that if I change volume in one object it does not touch volume of other object. but currently it does when I call IMFSimpleAudioVolume::SetMasterVolume

How do I achieve that? is it possible to have master volume separate for each media session? for example having a master volume and volume control for separate media sessions.

Thank you a lot, any advice is welcome!

[Duthomhas]

As always, read the docs.
https://docs.microsoft.com/en-us/windows/desktop/api/mfidl/nn-mfidl-imfsimpleaudiovolume

Remarks
To control the volume levels of individual channels, use the IMFAudioStreamVolume interface. The IMFAudioStreamVolume interface is supported by the SAR only.

Hope this helps.

[malibor]

Thanks a lot, that indeed worked!

even though the docs don't explicitly say IMFAudioStreamVolume is per stream volume control, just that it controls individual channels which is not the same IMO.