feat: Add experimental rewrite of go2rtc live provider (MSE/WebRTC/MP4/MJPEG) (#2580)

- Closes #2556 - Closes #2450 **Key intended features:** - go2rtc compatible - 100% test coverage to significantly improve ability to test, maintain and work around browser weirdnesses (e.g. Safari). - Written from the ground up in the style of the rest of the project. **To use:** - Change `live_provider` from `go2rtc` to `go2rtc-experimental`.
2026-07-14 14:22:41 -07:00
parent 5662e48c22
commit c02c692f68
125 changed files with 9608 additions and 807 deletions
@@ -0,0 +1,75 @@
+import { assert, describe, expect, it } from 'vitest';
+
+import {
+  LAG_SAMPLE_WINDOW_SIZE,
+  NonWebKitLiveEdgeStrategy,
+} from '../../../../../../../src/components-lib/live/providers/go2rtc-experimental/utils/live-edge-tracker/non-webkit';
+import { createStatus } from './test-utils';
+
+describe('NonWebKitLiveEdgeStrategy', () => {
+  it('should play at realtime when close to the live edge', () => {
+    const strategy = new NonWebKitLiveEdgeStrategy();
+    expect(strategy.next(createStatus(20, 18))).toEqual({ action: 'rate', rate: 1 });
+  });
+
+  it('should nudge the rate up when lag exceeds the stream norm', () => {
+    const strategy = new NonWebKitLiveEdgeStrategy();
+    for (let i = 0; i < LAG_SAMPLE_WINDOW_SIZE; ++i) {
+      strategy.next(createStatus(20, 19));
+    }
+
+    const action = strategy.next(createStatus(20, 15));
+
+    assert(action.action === 'rate');
+    expect(action.rate).toBeGreaterThan(1);
+    expect(action.rate).toBeLessThanOrEqual(2);
+  });
+
+  it('should cap the catch-up rate', () => {
+    const strategy = new NonWebKitLiveEdgeStrategy();
+    for (let i = 0; i < LAG_SAMPLE_WINDOW_SIZE; ++i) {
+      strategy.next(createStatus(20, 20));
+    }
+
+    expect(strategy.next(createStatus(60, 10))).toEqual({ action: 'rate', rate: 2 });
+  });
+
+  it('should stay near realtime within the stream normal lag', () => {
+    const strategy = new NonWebKitLiveEdgeStrategy();
+    for (let i = 0; i < LAG_SAMPLE_WINDOW_SIZE; ++i) {
+      strategy.next(createStatus(24, 20));
+    }
+
+    const action = strategy.next(createStatus(24, 20));
+
+    assert(action.action === 'rate');
+    expect(action.rate).toBeCloseTo(1, 2);
+  });
+
+  it('should catch up hard before any baseline samples exist', () => {
+    const strategy = new NonWebKitLiveEdgeStrategy();
+
+    // The very first sample is taken while already catching up, so it is
+    // excluded and there is no average to temper the threshold.
+    expect(strategy.next(createStatus(20, 15, { playbackRate: 2 }))).toEqual({
+      action: 'rate',
+      rate: 2,
+    });
+  });
+
+  it('should drop stale lag samples as the stream recovers', () => {
+    const strategy = new NonWebKitLiveEdgeStrategy();
+    for (let i = 0; i < LAG_SAMPLE_WINDOW_SIZE; ++i) {
+      strategy.next(createStatus(26, 20));
+    }
+    // A full window of low lag evicts the earlier high-lag samples.
+    for (let i = 0; i < LAG_SAMPLE_WINDOW_SIZE; ++i) {
+      strategy.next(createStatus(21, 20));
+    }
+
+    const action = strategy.next(createStatus(25, 20));
+
+    assert(action.action === 'rate');
+    expect(action.rate).toBeGreaterThan(1.1);
+  });
+});