webrtc/simulcast/vp9-scalability-mode.https.html

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<meta charset=utf-8>
<title>RTCPeerConnection Simulcast Tests</title>
<meta name="timeout" content="long">
<script src="../third_party/sdp/sdp.js"></script>
<script src="simulcast.js"></script>
<script src="../RTCPeerConnection-helper.js"></script>
<script src="/resources/testharness.js"></script>
<script src="/resources/testharnessreport.js"></script>
<script src="/resources/testdriver.js"></script>
<script src="/resources/testdriver-vendor.js"></script>
<script src="../../mediacapture-streams/permission-helper.js"></script>
<script>
promise_test(async t => {
  assert_implements('getCapabilities' in RTCRtpSender, 'RTCRtpSender.getCapabilities not supported');
  assert_implements(RTCRtpSender.getCapabilities('video').codecs.find(c => c.mimeType === 'video/VP9'), 'VP9 not supported');

  const rids = [0, 1];
  const pc1 = new RTCPeerConnection();
  t.add_cleanup(() => pc1.close());
  const pc2 = new RTCPeerConnection();
  t.add_cleanup(() => pc2.close());

  // This is not a scalability mode test (see wpt/webrtc-svc/ for those) but a
  // VP9 simulcast test. Setting `scalabilityMode` should not be needed, however
  // many browsers interprets multiple VP9 encodings to mean multiple spatial
  // layers by default. During a transition period, Chromium-based browsers
  // requires explicitly specifying the scalability mode as a way to opt-in to
  // spec-compliant simulcast. See also wpt/webrtc/simulcast/vp9.https.html for
  // a version of this test that does not set the scalability mode.
  const scalabilityMode = 'L1T2';
  return negotiateSimulcastAndWaitForVideo(
      t, rids, pc1, pc2, {mimeType: 'video/VP9'}, scalabilityMode);
}, 'VP9 simulcast setup with two streams and L1T2 set');
</script>