Chrome responds with SDP error when sdp answer contains only pcmu or pcma.
Reported by
josh.mac...@frozenmountain.com,
Oct 19 2017
|
|||
Issue description
UserAgent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_12_5) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/62.0.3202.62 Safari/537.36
Steps to reproduce the problem:
Run the following in the console:
answer = {"type": "answer", "sdp": "v=0\r\no=- 8784491778466222000 1 IN IP4 127.0.0.1\r\ns=Client\r\nt=0 0\r\na=ice-options:trickle\r\nm=audio 9 UDP/TLS/RTP/SAVPF 0\r\nc=IN IP4 0.0.0.0\r\nb=TIAS:32768\r\nb=AS:32\r\na=ice-ufrag:77231125\r\na=ice-pwd:ff66f53f260a0a7386887b5ef397fb59\r\na=fingerprint:sha-256 D5:EB:3E:3E:28:D9:1C:FB:EA:90:95:CC:00:07:04:11:43:16:82:F8:D8:5A:06:90:B4:C0:47:1E:00:55:B3:40\r\na=setup:active\r\na=rtcp-mux\r\na=rtcp:9 IN IP4 0.0.0.0\r\na=sendrecv\r\na=rtpmap:0 PCMU/8000\r\na=ssrc:413010878 cname:1734be1773464b498929513c9c60d5f9\r\nm=video 9 UDP/TLS/RTP/SAVPF 96\r\nc=IN IP4 0.0.0.0\r\nb=TIAS:1048576\r\nb=AS:1024\r\na=ice-ufrag:cdaf4af9\r\na=ice-pwd:f6c539cc377af4d2f7550b6b5b434b9e\r\na=fingerprint:sha-256 D5:EB:3E:3E:28:D9:1C:FB:EA:90:95:CC:00:07:04:11:43:16:82:F8:D8:5A:06:90:B4:C0:47:1E:00:55:B3:40\r\na=setup:active\r\na=rtcp-mux\r\na=rtcp:9 IN IP4 0.0.0.0\r\na=sendrecv\r\na=rtpmap:96 VP8/90000\r\na=rtcp-fb:96 nack\r\na=rtcp-fb:96 nack pli\r\na=ssrc:1443172014 cname:1734be1773464b498929513c9c60d5f9\r\n"};
navigator.getUserMedia({video:true, audio:true}, function(stream) {
var pc = new RTCPeerConnection();
pc.addStream(stream);
pc.createOffer().then(offer => {
pc.setLocalDescription(offer).
then(function () {
pc.setRemoteDescription(answer)
});
});
}, function (error) { console.log(error); });
Accept the camera/mic usage if needed.
What is the expected behavior?
Should be able to use the SDP message without error (Firefox does)
What went wrong?
An error: "Session error description: Failed to set remote audio description send parameters" occurs.
Did this work before? N/A
Does this work in other browsers? Yes
Chrome version: 62.0.3202.62 Channel: beta
OS Version: OS X 10.12.5
Flash Version:
,
Oct 20 2017
,
Oct 20 2017
The underlying error is "Failed to set codec PCMU to bitrate 32000 bps, requires at least 64000 bps." 32000 comes from the "b=AS"/"b=TIAS", and the 64000 limit comes from code introduced in this CL: https://codereview.webrtc.org/2962653002/ But based on the tests in that CL, it looks like this was intentional. Tentatively marking as "WontFix", CCing some people who may know more definitively.
,
Oct 20 2017
PCMu uses one byte per sample, so mono PCMu at 8000 Hz -> 64000 bps. So it would seem logical to refuse to set the bitrate to 32000.
,
Oct 20 2017
Should the AS and TIAS lines then be ignored if PCMU or PCMA is used? I presume that's what firefox does. |
|||
►
Sign in to add a comment |
|||
Comment 1 by manoranj...@chromium.org
, Oct 19 2017