ConvolverNode: Make no. of output channels user controllable

[olivierthereaux]

Originally reported on W3C Bugzilla ISSUE-17542 Tue, 19 Jun 2012 08:30:43 GMT
Reported by Marcus Geelnard (Opera)
Assigned to

https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html#ConvolverNode

Currently, the number of output channels of the ConvolverNode is controlled by the number of output channels of the AudioContext (although it's not very clear in the spec).

I think it would be a better idea to be able to control the number of output channels of the ConvolverNode upon construction rather than relying on the AudioDestinationNode.

It would give you more freedom to do custom processing, and makes the actual usage of the impulse response channels much more user controllable.

The last point is important, since the number of output channels controls which matrixing operation will be used.

[cwilso]

Actually, I think the number of output channels of the Convolver is controlled by the number of channels of the convolution impulse buffer? It would get downmixed at the destination, of course, like anything else.

[joeberkovitz]

My sense is that by resolving #97 and defining of the node's output channel count as equivalent to that of the impulse buffer, we will be out of the woods. I don't think we need to build in additional channel mixing smarts into this node, assuming I read the issue correctly.

[cwilso]

I agree.