webrtc wpt: test that additional codecs can be used
which tests "MAY include formats that are locally supported but not
present in the offer" from
https://www.rfc-editor.org/rfc/rfc8829.html#section-5.3.1
BUG=None
Change-Id: Ifc35264b46edf14befe88704d98850bb71bb683d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/5110019
Reviewed-by: Harald Alvestrand <hta@chromium.org>
Commit-Queue: Philipp Hancke <phancke@microsoft.com>
Cr-Commit-Position: refs/heads/main@{#1237087}
diff --git a/webrtc/protocol/additional-codecs.html b/webrtc/protocol/additional-codecs.html
new file mode 100644
index 0000000..5462d61
--- /dev/null
+++ b/webrtc/protocol/additional-codecs.html
@@ -0,0 +1,56 @@
+<!doctype html>
+<meta charset=utf-8>
+<title>Send additional codec supported by the other side</title>
+<meta name=timeout content=long>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="../RTCPeerConnection-helper.js"></script>
+<script>
+'use strict';
+// Tests behaviour from
+// https://www.rfc-editor.org/rfc/rfc8829.html#section-5.3.1
+// in particular "but MAY include formats that are locally
+// supported but not present in the offer"
+
+promise_test(async t => {
+ const pc1 = new RTCPeerConnection();
+ t.add_cleanup(() => pc1.close());
+ const pc2 = new RTCPeerConnection();
+ t.add_cleanup(() => pc2.close());
+ exchangeIceCandidates(pc1, pc2);
+
+ const stream = await getNoiseStream({video: true});
+ t.add_cleanup(() => stream.getTracks().forEach(t => t.stop()));
+ pc1.addTrack(stream.getTracks()[0], stream);
+ pc2.addTrack(stream.getTracks()[0], stream);
+ // Only offer VP8.
+ pc1.getTransceivers()[0].setCodecPreferences([{
+ clockRate: 90000,
+ mimeType: 'video/VP8'
+ }]);
+ await pc1.setLocalDescription();
+
+ // Add H264 to the SDP.
+ const sdp = pc1.localDescription.sdp.split('\n')
+ .map(l => {
+ if (l.startsWith('m=')) {
+ return l.trim() + ' 63'; // 63 is the least-likely to be used PT.
+ }
+ return l.trim();
+ }).join('\r\n') +
+ 'a=rtpmap:63 H264/90000\r\n' +
+ 'a=fmtp:63 level-asymmetry-allowed=1;packetization-mode=1;profile-level-id=42e01f\r\n'
+ await pc2.setRemoteDescription({
+ type: 'offer',
+ sdp: sdp.replaceAll('VP8', 'no-such-codec'), // Remove VP8
+ });
+ await pc2.setLocalDescription();
+ await pc1.setRemoteDescription(pc2.localDescription);
+
+ await listenToConnected(pc2);
+ const stats = await pc1.getStats();
+ const rtp = [...stats.values()].find(({type}) => type === 'outbound-rtp');
+ assert_true(!!rtp);
+ assert_equals(stats.get(rtp.codecId).mimeType, 'video/H264');
+}, 'Listing an additional codec in the answer causes it to be sent.');
+</script>
