[renderer] Enable rendering of mono/stereo to all formats + add tests
Follow up to #1419 (closed) for the external renderer and adding testcases for the newly available output formats.
| Input Format | Output Format | Rendering path |
|---|---|---|
| Mono | Mono | Not changed in this MR (passthrough) |
| Mono | Stereo | Not changed in this MR (passive upmix) |
| Mono | Multichannel | Not changed in this MR (mixing matrices) |
| Mono | Ambisonics | Passthrough to channel index 0 (W/Omni) 1 |
| Mono | Binaural | Non-diegetic upmix |
| Mono | Binaural (ROOM_IR) | Non-diegetic upmix |
| Stereo | Mono | Not changed in this MR (passive downmix) |
| Stereo | Stereo | Not changed in this MR (passthrough) |
| Stereo | Multichannel | Not changed in this MR (mixing matrices) |
| Stereo | Ambisonics | M/S routing to W and Y (W = \frac{L+R}{2}; Y = \frac{L-R}{2}) 1 |
| Stereo | Binaural | Passthrough as Stereo |
| Stereo | Binaural (ROOM_IR) | Passthrough as Stereo |
Edited by Archit Tamarapu