feat: advanced media quality settings UI and config-driven defaults

locales/en/app.json

@@ -188,13 +188,23 @@
   "room_auth_view_ssla_caption": "By clicking \"Join call now\", you agree to our <2>Software and Services License Agreement (SSLA)</2>",
   "screenshare_button_label": "Share screen",
   "settings": {
+    "advanced_camera_description": "Configure resolution, framerate, bitrate, and codec for camera video. Changes apply on next call join.",
+    "advanced_camera_label": "Advanced camera settings",
+    "advanced_screen_share_description": "Configure resolution, framerate, bitrate, and codec for screen sharing",
+    "advanced_screen_share_label": "Advanced screen share settings",
+    "audio_processing_description": "Changes apply on next call join.",
+    "audio_processing_header": "Audio processing",
     "audio_tab": {
       "effect_volume_description": "Adjust the volume at which reactions and hand raised effects play.",
       "effect_volume_label": "Sound effect volume"
     },
+    "auto_gain_control_label": "Automatic gain control",
     "background_blur_header": "Background",
     "background_blur_label": "Blur the background of the video",
+    "bitrate_label": "Bitrate",
     "blur_not_supported_by_browser": "(Background blur is not supported by this device.)",
+    "camera_header": "Camera quality",
+    "codec_label": "Codec",
     "developer_tab_title": "Developer",
     "devices": {
       "camera": "Camera",
@@ -209,12 +219,15 @@
       "speaker": "Speaker",
       "speaker_numbered": "Speaker {{n}}"
     },
+    "echo_cancellation_label": "Echo cancellation",
     "feedback_tab_body": "If you are experiencing issues or simply would like to provide some feedback, please send us a short description below.",
     "feedback_tab_description_label": "Your feedback",
     "feedback_tab_h4": "Submit feedback",
     "feedback_tab_send_logs_label": "Include debug logs",
     "feedback_tab_thank_you": "Thanks, we received your feedback!",
     "feedback_tab_title": "Feedback",
+    "framerate_label": "Framerate",
+    "noise_suppression_label": "Noise suppression",
     "opt_in_description": "<0></0><1></1>You may withdraw consent by unchecking this box. If you are currently in a call, this setting will take effect at the end of the call.",
     "preferences_tab": {
       "developer_mode_label": "Developer mode",
@@ -226,7 +239,9 @@
       "reactions_show_label": "Show reactions",
       "show_hand_raised_timer_description": "Show a timer when a participant raises their hand",
       "show_hand_raised_timer_label": "Show hand raise duration"
-    }
+    },
+    "resolution_label": "Resolution",
+    "screen_share_header": "Screen sharing"
   },
   "star_rating_input_label_one": "{{count}} star",
   "star_rating_input_label_other": "{{count}} stars",

src/Slider.tsx

@@ -31,6 +31,11 @@ interface Props {
   max: number;
   step: number;
   disabled?: boolean;
+  /**
+   * Custom formatter for the tooltip label. If not provided, the value is
+   * displayed as a percentage.
+   */
+  tooltipFormatter?: (value: number) => string;
 }
 
 /**
@@ -46,6 +51,7 @@ export const Slider: FC<Props> = ({
   max,
   step,
   disabled,
+  tooltipFormatter,
 }) => {
   const onValueChange = useCallback(
     ([v]: number[]) => onValueChangeProp(v),
@@ -71,7 +77,14 @@ export const Slider: FC<Props> = ({
         <Range className={styles.highlight} />
       </Track>
       {/* Note: This is expected not to be visible on mobile.*/}
-      <Tooltip placement="top" label={Math.round(value * 100).toString() + "%"}>
+      <Tooltip
+        placement="top"
+        label={
+          tooltipFormatter
+            ? tooltipFormatter(value)
+            : Math.round(value * 100).toString() + "%"
+        }
+      >
         <Thumb className={styles.handle} aria-label={label} />
       </Tooltip>
     </Root>

src/config/ConfigOptions.ts

@@ -85,6 +85,61 @@ export interface ConfigOptions {
    */
   ssla?: string;
 
+  /**
+   * Media quality settings for video and screen sharing.
+   * These override the hardcoded LiveKit defaults.
+   */
+  media_quality?: {
+    /**
+     * Video codec preference. The server must also have the codec enabled.
+     * @default "vp8"
+     */
+    video_codec?: "vp8" | "vp9" | "h264" | "av1";
+
+    /**
+     * Camera video settings.
+     */
+    video?: {
+      /** Max resolution height in pixels (e.g. 720, 1080, 1440). @default 720 */
+      max_resolution?: number;
+      /** Max bitrate in bits per second. @default 1700000 */
+      max_bitrate?: number;
+      /** Max framerate. @default 30 */
+      max_framerate?: number;
+      /**
+       * Simulcast layers as an array of {height, bitrate} objects,
+       * ordered from lowest to highest quality.
+       * @default [{height: 180, bitrate: 160000}, {height: 360, bitrate: 450000}]
+       */
+      simulcast_layers?: Array<{
+        height: number;
+        bitrate: number;
+      }>;
+    };
+
+    /**
+     * Screen share settings.
+     */
+    screen_share?: {
+      /** Max resolution height in pixels. @default 1080 */
+      max_resolution?: number;
+      /** Max bitrate in bits per second. @default 5000000 */
+      max_bitrate?: number;
+      /** Max framerate. @default 30 */
+      max_framerate?: number;
+      /**
+       * Simulcast layers for screen sharing as an array of {height, bitrate, framerate} objects,
+       * ordered from lowest to highest quality. If omitted, LiveKit SDK defaults apply (1 extra
+       * layer at half resolution).
+       */
+      simulcast_layers?: Array<{
+        height: number;
+        bitrate: number;
+        framerate?: number;
+      }>;
+    };
+  };
+
   media_devices?: {
     /**
      * Defines whether participants should start with audio enabled by default.
@@ -156,6 +211,24 @@ export interface ResolvedConfigOptions extends ConfigOptions {
     };
   };
   ssla: string;
+  media_quality: Required<
+    Pick<NonNullable<ConfigOptions["media_quality"]>, "video_codec">
+  > & {
+    video: Required<
+      Pick<
+        NonNullable<NonNullable<ConfigOptions["media_quality"]>["video"]>,
+        "max_resolution" | "max_bitrate" | "max_framerate"
+      >
+    >;
+    screen_share: Required<
+      Pick<
+        NonNullable<
+          NonNullable<ConfigOptions["media_quality"]>["screen_share"]
+        >,
+        "max_resolution" | "max_bitrate" | "max_framerate"
+      >
+    >;
+  };
 }
 
 export const DEFAULT_CONFIG: ResolvedConfigOptions = {
@@ -169,4 +242,17 @@ export const DEFAULT_CONFIG: ResolvedConfigOptions = {
     feature_use_device_session_member_events: true,
   },
   ssla: "https://static.element.io/legal/element-software-and-services-license-agreement-uk-1.pdf",
+  media_quality: {
+    video_codec: "vp8",
+    video: {
+      max_resolution: 720,
+      max_bitrate: 1_700_000,
+      max_framerate: 30,
+    },
+    screen_share: {
+      max_resolution: 1080,
+      max_bitrate: 5_000_000,
+      max_framerate: 30,
+    },
+  },
 };

src/initializer.tsx

@@ -26,6 +26,7 @@ import {
 
 import { getUrlParams } from "./UrlParams";
 import { Config } from "./config/Config";
+import { seedSettingsFromConfig } from "./settings/settings";
 import { platform } from "./Platform";
 import { isFailure } from "./utils/fetch";
 import { initializeWidget } from "./widget";
@@ -220,6 +221,7 @@ export class Initializer {
       this.loadStates.config = LoadState.Loading;
       Config.init().then(
         () => {
+          seedSettingsFromConfig(Config.get().media_quality);
           this.loadStates.config = LoadState.Loaded;
           this.initStep(resolve);
         },

src/livekit/options.test.ts

@@ -0,0 +1,165 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE in the repository root for full details.
+*/
+
+import { describe, expect, it, vi } from "vitest";
+import { VideoPresets } from "livekit-client";
+
+import { buildLiveKitOptions, getLiveKitOptions } from "./options";
+import { Config } from "../config/Config";
+
+vi.mock("../config/Config", () => ({
+  Config: {
+    get: vi.fn(),
+  },
+}));
+
+describe("buildLiveKitOptions", () => {
+  it("returns sensible defaults with no config", () => {
+    const opts = buildLiveKitOptions();
+    expect(opts.adaptiveStream).toBe(true);
+    expect(opts.dynacast).toBe(true);
+    expect(opts.videoCaptureDefaults?.resolution).toEqual(
+      VideoPresets.h720.resolution,
+    );
+    expect(opts.publishDefaults?.videoCodec).toBe("vp8");
+    expect(opts.publishDefaults?.videoEncoding).toEqual({
+      maxBitrate: 1_700_000,
+      maxFramerate: 30,
+    });
+    expect(opts.publishDefaults?.screenShareEncoding).toEqual({
+      maxBitrate: 5_000_000,
+      maxFramerate: 30,
+    });
+    expect(opts.publishDefaults?.videoSimulcastLayers).toEqual([
+      VideoPresets.h180,
+      VideoPresets.h360,
+    ]);
+  });
+
+  it("applies video codec from config", () => {
+    const opts = buildLiveKitOptions({ video_codec: "vp9" });
+    expect(opts.publishDefaults?.videoCodec).toBe("vp9");
+  });
+
+  it("applies video resolution and encoding from config", () => {
+    const opts = buildLiveKitOptions({
+      video: {
+        max_resolution: 1080,
+        max_bitrate: 3_000_000,
+        max_framerate: 60,
+      },
+    });
+    expect(opts.videoCaptureDefaults?.resolution).toEqual(
+      VideoPresets.h1080.resolution,
+    );
+    expect(opts.publishDefaults?.videoEncoding).toEqual({
+      maxBitrate: 3_000_000,
+      maxFramerate: 60,
+    });
+  });
+
+  it("applies screen share encoding from config", () => {
+    const opts = buildLiveKitOptions({
+      screen_share: {
+        max_bitrate: 8_000_000,
+        max_framerate: 15,
+      },
+    });
+    expect(opts.publishDefaults?.screenShareEncoding).toEqual({
+      maxBitrate: 8_000_000,
+      maxFramerate: 15,
+    });
+  });
+
+  it("uses DEFAULT_CONFIG defaults when only resolution is set", () => {
+    const opts = buildLiveKitOptions({
+      screen_share: {
+        max_resolution: 720,
+      },
+    });
+    // Bitrate and framerate fall back to DEFAULT_CONFIG, not the preset
+    expect(opts.publishDefaults?.screenShareEncoding).toEqual({
+      maxBitrate: 5_000_000,
+      maxFramerate: 30,
+    });
+  });
+
+  it("applies custom video simulcast layers", () => {
+    const opts = buildLiveKitOptions({
+      video: {
+        simulcast_layers: [
+          { height: 180, bitrate: 100_000 },
+          { height: 360, bitrate: 300_000 },
+          { height: 540, bitrate: 600_000 },
+        ],
+        max_framerate: 24,
+      },
+    });
+    const layers = opts.publishDefaults?.videoSimulcastLayers;
+    expect(layers).toHaveLength(3);
+    expect(layers?.[0]).toMatchObject({
+      width: 320,
+      height: 180,
+      encoding: { maxBitrate: 100_000, maxFramerate: 24 },
+    });
+    expect(layers?.[2]).toMatchObject({
+      width: 960,
+      height: 540,
+      encoding: { maxBitrate: 600_000, maxFramerate: 24 },
+    });
+  });
+
+  it("applies custom screen share simulcast layers", () => {
+    const opts = buildLiveKitOptions({
+      screen_share: {
+        simulcast_layers: [{ height: 540, bitrate: 1_000_000, framerate: 5 }],
+      },
+    });
+    const layers = opts.publishDefaults?.screenShareSimulcastLayers;
+    expect(layers).toHaveLength(1);
+    expect(layers?.[0]).toMatchObject({
+      width: 960,
+      height: 540,
+      encoding: { maxBitrate: 1_000_000, maxFramerate: 5 },
+    });
+  });
+
+  it("does not include screenShareSimulcastLayers when not configured", () => {
+    const opts = buildLiveKitOptions();
+    expect(opts.publishDefaults?.screenShareSimulcastLayers).toBeUndefined();
+  });
+
+  it("backupCodec always uses stock VP8 720p encoding", () => {
+    const opts = buildLiveKitOptions({
+      video_codec: "av1",
+      video: { max_bitrate: 10_000_000, max_framerate: 60 },
+    });
+    const backup = opts.publishDefaults?.backupCodec as {
+      codec: string;
+      encoding: { maxBitrate: number; maxFramerate: number };
+    };
+    expect(backup.codec).toBe("vp8");
+    expect(backup.encoding).toEqual(VideoPresets.h720.encoding);
+  });
+});
+
+describe("getLiveKitOptions", () => {
+  it("reads from Config singleton", () => {
+    vi.mocked(Config.get).mockReturnValue({
+      media_quality: { video_codec: "h264" },
+    } as ReturnType<typeof Config.get>);
+    const opts = getLiveKitOptions();
+    expect(opts.publishDefaults?.videoCodec).toBe("h264");
+  });
+
+  it("throws when Config is not initialized", () => {
+    vi.mocked(Config.get).mockImplementation(() => {
+      throw new Error("Config not initialized");
+    });
+    expect(() => getLiveKitOptions()).toThrow("Config not initialized");
+  });
+});