livstream-player
Version:
A lightweight livestream player SDK for React apps
208 lines (207 loc) • 8.94 kB
JavaScript
export const editOffer = (sdp, nonAdvertisedCodecs) => {
const sections = sdp.split('m=');
for (let i = 0; i < sections.length; i++) {
if (sections[i].startsWith('audio')) {
sections[i] = enableStereoOpus(sections[i]);
if (nonAdvertisedCodecs.includes('pcma/8000/2')) {
sections[i] = enableStereoPcmau(sections[i]);
}
if (nonAdvertisedCodecs.includes('multiopus/48000/6')) {
sections[i] = enableMultichannelOpus(sections[i]);
}
if (nonAdvertisedCodecs.includes('L16/48000/2')) {
sections[i] = enableL16(sections[i]);
}
break;
}
}
return sections.join('m=');
};
const enableMultichannelOpus = (section) => {
let lines = section.split('\r\n');
let payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} multiopus/48000/3`);
lines.splice(lines.length - 1, 0, `a=fmtp:${payloadType} channel_mapping=0,2,1;num_streams=2;coupled_streams=1`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} multiopus/48000/4`);
lines.splice(lines.length - 1, 0, `a=fmtp:${payloadType} channel_mapping=0,1,2,3;num_streams=2;coupled_streams=2`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} multiopus/48000/5`);
lines.splice(lines.length - 1, 0, `a=fmtp:${payloadType} channel_mapping=0,4,1,2,3;num_streams=3;coupled_streams=2`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} multiopus/48000/6`);
lines.splice(lines.length - 1, 0, `a=fmtp:${payloadType} channel_mapping=0,4,1,2,3,5;num_streams=4;coupled_streams=2`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} multiopus/48000/7`);
lines.splice(lines.length - 1, 0, `a=fmtp:${payloadType} channel_mapping=0,4,1,2,3,5,6;num_streams=4;coupled_streams=4`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} multiopus/48000/8`);
lines.splice(lines.length - 1, 0, `a=fmtp:${payloadType} channel_mapping=0,6,1,4,5,2,3,7;num_streams=5;coupled_streams=4`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
return lines.join('\r\n');
};
const enableStereoOpus = (section) => {
let opusPayloadFormat = '';
let lines = section.split('\r\n');
for (let i = 0; i < lines.length; i++) {
if (lines[i].startsWith('a=rtpmap:') &&
lines[i].toLowerCase().includes('opus/')) {
opusPayloadFormat = lines[i].slice('a=rtpmap:'.length).split(' ')[0];
break;
}
}
if (opusPayloadFormat === '') {
return section;
}
for (let i = 0; i < lines.length; i++) {
if (lines[i].startsWith('a=fmtp:' + opusPayloadFormat + ' ')) {
if (!lines[i].includes('stereo')) {
lines[i] += ';stereo=1';
}
if (!lines[i].includes('sprop-stereo')) {
lines[i] += ';sprop-stereo=1';
}
}
}
return lines.join('\r\n');
};
const findFreePayloadType = (firstLine) => {
const payloadTypes = firstLine.split(' ').slice(3);
for (let i = 96; i <= 127; i++) {
if (!payloadTypes.includes(i.toString())) {
return i.toString();
}
}
throw Error('unable to find a free payload type');
};
const enableStereoPcmau = (section) => {
let lines = section.split('\r\n');
let payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} PCMU/8000/2`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} PCMA/8000/2`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
return lines.join('\r\n');
};
const enableL16 = (section) => {
let lines = section.split('\r\n');
let payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} L16/8000/2`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} L16/16000/2`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
payloadType = findFreePayloadType(lines[0]);
lines[0] += ` ${payloadType}`;
lines.splice(lines.length - 1, 0, `a=rtpmap:${payloadType} L16/48000/2`);
lines.splice(lines.length - 1, 0, `a=rtcp-fb:${payloadType} transport-cc`);
return lines.join('\r\n');
};
export const parseOffer = (sdp) => {
const ret = {
iceUfrag: '',
icePwd: '',
medias: [],
};
for (const line of sdp.split('\r\n')) {
if (line.startsWith('m=')) {
ret.medias.push(line.slice('m='.length));
}
else if (ret.iceUfrag === '' && line.startsWith('a=ice-ufrag:')) {
ret.iceUfrag = line.slice('a=ice-ufrag:'.length);
}
else if (ret.icePwd === '' && line.startsWith('a=ice-pwd:')) {
ret.icePwd = line.slice('a=ice-pwd:'.length);
}
}
return ret;
};
export const supportsNonAdvertisedCodec = (codec, fmtp) => new Promise((resolve, reject) => {
const pc = new RTCPeerConnection({ iceServers: [] });
pc.addTransceiver('audio', { direction: 'recvonly' });
pc.createOffer()
.then((offer) => {
if (offer.sdp.includes(' ' + codec)) {
// codec is advertised, there's no need to add it manually
resolve(false);
return;
}
const sections = offer.sdp.split('m=audio');
const lines = sections[1].split('\r\n');
lines[0] += ' 118';
lines.splice(lines.length - 1, 0, 'a=rtpmap:118 ' + codec);
if (fmtp !== undefined) {
lines.splice(lines.length - 1, 0, 'a=fmtp:118 ' + fmtp);
}
sections[1] = lines.join('\r\n');
offer.sdp = sections.join('m=audio');
return pc.setLocalDescription(offer);
})
.then(() => {
return pc.setRemoteDescription(new RTCSessionDescription({
type: 'answer',
sdp: 'v=0\r\n' +
'o=- 6539324223450680508 0 IN IP4 0.0.0.0\r\n' +
's=-\r\n' +
't=0 0\r\n' +
'a=fingerprint:sha-256 0D:9F:78:15:42:B5:4B:E6:E2:94:3E:5B:37:78:E1:4B:54:59:A3:36:3A:E5:05:EB:27:EE:8F:D2:2D:41:29:25\r\n' +
'm=audio 9 UDP/TLS/RTP/SAVPF 118\r\n' +
'c=IN IP4 0.0.0.0\r\n' +
'a=ice-pwd:7c3bf4770007e7432ee4ea4d697db675\r\n' +
'a=ice-ufrag:29e036dc\r\n' +
'a=sendonly\r\n' +
'a=rtcp-mux\r\n' +
'a=rtpmap:118 ' +
codec +
'\r\n' +
(fmtp !== undefined ? 'a=fmtp:118 ' + fmtp + '\r\n' : ''),
}));
})
.then(() => {
resolve(true);
})
.catch((err) => {
resolve(false);
})
.finally(() => {
pc.close();
});
});
export const generateSdpFragment = (od, candidates) => {
const candidatesByMedia = {};
for (const candidate of candidates) {
const mid = candidate.sdpMLineIndex;
if (candidatesByMedia[mid] === undefined) {
candidatesByMedia[mid] = [];
}
candidatesByMedia[mid].push(candidate);
}
let frag = 'a=ice-ufrag:' + od.iceUfrag + '\r\n' + 'a=ice-pwd:' + od.icePwd + '\r\n';
let mid = 0;
for (const media of od.medias) {
if (candidatesByMedia[mid] !== undefined) {
frag += 'm=' + media + '\r\n' + 'a=mid:' + mid + '\r\n';
for (const candidate of candidatesByMedia[mid]) {
frag += 'a=' + candidate.candidate + '\r\n';
}
}
mid++;
}
return frag;
};