feat(streamer): add support for NVIDIA AV1 video encoder options in W…

…ebRTC streamer

Anbox Cloud has supported the AV1 video encoder for some time. The
relevant options for NVIDIA video encoders apply not only to H.264
but also to AV1.

This change introduces support for NVIDIA AV1 video encoder options
in the WebRTC streamer.

reference/webrtc-streamer.md

@@ -10,13 +10,13 @@ The configuration file uses the JSON format. It has the following structure:
 | Name | Value type | Default | Description |
 |------|------------|---------|-------------|
 | `video.bitrate_limits` | array of objects | `[]` | Bitrate limits to apply to the video encoder. |
-| `nvidia_h264.multipass` | bool | `false` | If set to true, multi-pass encoding is enabled. |
-| `nvidia_h264.multipass_quarter_resolution` | bool | `false` | If set to true, multi-pass encoding will be run only for a quarter of a frame's resolution. |
-| `nvidia_h264.aq` | bool | `false` | If set to true, adaptive quantisation is enabled. |
-| `nvidia_h264.aq_strength` | integer | `0` | Strength of adaptive quantisation: a value from `1` (least aggressive) to `15` (most aggressive). `0` means the encoder will automatically decide. |
-| `nvidia_h264.preset` | integer | `0` | Preset to use (a value from `1` to `7`). `0` means Anbox will automatically decide. |
+| `nvidia_h264.multipass`<br>`nvidia_av1.multipass` | bool | `false` | If set to true, multi-pass encoding is enabled. |
+| `nvidia_h264.multipass_quarter_resolution`<br>`nvidia_av1.multipass_quarter_resolution` | bool | `false` | If set to true, multi-pass encoding will be run only for a quarter of a frame's resolution. |
+| `nvidia_h264.aq`<br>`nvidia_av1.aq` | bool | `false` | If set to true, adaptive quantisation is enabled. |
+| `nvidia_h264.aq_strength`<br>`nvidia_av1.aq_strength` | integer | `0` | Strength of adaptive quantisation: a value from `1` (least aggressive) to `15` (most aggressive). `0` means the encoder will automatically decide. |
+| `nvidia_h264.preset`<br>`nvidia_av1.preset` | integer | `0` | Preset to use (a value from `1` to `7`). `0` means Anbox will automatically decide. |
 
-See the [NVENC Video Encoder API](https://docs.nvidia.com/video-technologies/video-codec-sdk/11.0/nvenc-video-encoder-api-prog-guide/) documentation for more details on the `nvidia_h264` options.
+See the [NVENC Video Encoder API](https://docs.nvidia.com/video-technologies/video-codec-sdk/11.0/nvenc-video-encoder-api-prog-guide/) documentation for more details on the NVIDIA video encoder options.
 
 ## Video bitrate limits