/**
* Makes an <tt>RTCPREMBPacket</tt> that provides receiver feedback to the endpoint from which we
* receive.
*
* @return an <tt>RTCPREMBPacket</tt> that provides receiver feedback to the endpoint from which
* we receive.
*/
private RTCPREMBPacket makeRTCPREMBPacket() {
// TODO we should only make REMBs if REMB support has been advertised.
// Destination
RemoteBitrateEstimator remoteBitrateEstimator =
((VideoMediaStream) getStream()).getRemoteBitrateEstimator();
Collection<Integer> ssrcs = remoteBitrateEstimator.getSsrcs();
// TODO(gp) intersect with SSRCs from signaled simulcast layers
// NOTE(gp) The Google Congestion Control algorithm (sender side)
// doesn't seem to care about the SSRCs in the dest field.
long[] dest = new long[ssrcs.size()];
int i = 0;
for (Integer ssrc : ssrcs) dest[i++] = ssrc & 0xFFFFFFFFL;
// Exp & mantissa
long bitrate = remoteBitrateEstimator.getLatestEstimate();
if (bitrate == -1) return null;
if (logger.isDebugEnabled()) logger.debug("Estimated bitrate: " + bitrate);
// Create and return the packet.
// We use the stream's local source ID (SSRC) as the SSRC of packet
// sender.
long streamSSRC = getLocalSSRC();
return new RTCPREMBPacket(streamSSRC, /* mediaSSRC */ 0L, bitrate, dest);
}
/**
* Returns the SSRC paired with <tt>ssrc</tt> in an FID source-group, if any. If none is found,
* returns -1.
*
* @return the SSRC paired with <tt>ssrc</tt> in an FID source-group, if any. If none is found,
* returns -1.
*/
private long getPrimarySsrc(RawPacket pkt) {
MediaStreamTrackReceiver receiver = channel.getStream().getMediaStreamTrackReceiver();
if (receiver == null) {
if (logger.isDebugEnabled()) {
logger.debug("Dropping an incoming RTX packet from an unknown source.");
}
return -1;
}
RTPEncoding encoding = receiver.resolveRTPEncoding(pkt);
if (encoding == null) {
if (logger.isDebugEnabled()) {
logger.debug("Dropping an incoming RTX packet from an unknown source.");
}
return -1;
}
return encoding.getPrimarySSRC();
}
/**
* Removes the RTX encapsulation from a packet.
*
* @param pkt the packet to remove the RTX encapsulation from.
* @return the original media packet represented by {@code pkt}, or null if we couldn't
* reconstruct the original packet.
*/
private RawPacket deRtx(RawPacket pkt) {
boolean success = false;
if (pkt.getPayloadLength() - pkt.getPaddingSize() < 2) {
// We need at least 2 bytes to read the OSN field.
if (logger.isDebugEnabled()) {
logger.debug("Dropping an incoming RTX packet with padding only: " + pkt);
}
return null;
}
long mediaSsrc = getPrimarySsrc(pkt);
if (mediaSsrc != -1) {
if (rtxAssociatedPayloadType != -1) {
int osn = pkt.getOriginalSequenceNumber();
// Remove the RTX header by moving the RTP header two bytes
// right.
byte[] buf = pkt.getBuffer();
int off = pkt.getOffset();
System.arraycopy(buf, off, buf, off + 2, pkt.getHeaderLength());
pkt.setOffset(off + 2);
pkt.setLength(pkt.getLength() - 2);
pkt.setSSRC((int) mediaSsrc);
pkt.setSequenceNumber(osn);
pkt.setPayloadType(rtxAssociatedPayloadType);
success = true;
} else {
logger.warn(
"RTX packet received, but no APT is defined. Packet "
+ "SSRC "
+ pkt.getSSRCAsLong()
+ ", associated media"
+ " SSRC "
+ mediaSsrc);
}
}
// If we failed to handle the RTX packet, drop it.
return success ? pkt : null;
}
/**
* Implements {@link ControllerListener#controllerUpdate(ControllerEvent)}. Handles events from
* the <tt>Processor</tt>s that this instance uses to transcode media.
*
* @param ev the event to handle.
*/
public void controllerUpdate(ControllerEvent ev) {
if (ev == null || ev.getSourceController() == null) {
return;
}
Processor processor = (Processor) ev.getSourceController();
ReceiveStreamDesc desc = findReceiveStream(processor);
if (desc == null) {
logger.warn("Event from an orphaned processor, ignoring: " + ev);
return;
}
if (ev instanceof ConfigureCompleteEvent) {
if (logger.isInfoEnabled()) {
logger.info(
"Configured processor for ReceiveStream ssrc="
+ desc.ssrc
+ " ("
+ desc.format
+ ")"
+ " "
+ System.currentTimeMillis());
}
boolean audio = desc.format instanceof AudioFormat;
if (audio) {
ContentDescriptor cd = processor.setContentDescriptor(AUDIO_CONTENT_DESCRIPTOR);
if (!AUDIO_CONTENT_DESCRIPTOR.equals(cd)) {
logger.error(
"Failed to set the Processor content "
+ "descriptor to "
+ AUDIO_CONTENT_DESCRIPTOR
+ ". Actual result: "
+ cd);
removeReceiveStream(desc, false);
return;
}
}
for (TrackControl track : processor.getTrackControls()) {
Format trackFormat = track.getFormat();
if (audio) {
final long ssrc = desc.ssrc;
SilenceEffect silenceEffect;
if (Constants.OPUS_RTP.equals(desc.format.getEncoding())) {
silenceEffect = new SilenceEffect(48000);
} else {
// We haven't tested that the RTP timestamps survive
// the journey through the chain when codecs other than
// opus are in use, so for the moment we rely on FMJ's
// timestamps for non-opus formats.
silenceEffect = new SilenceEffect();
}
silenceEffect.setListener(
new SilenceEffect.Listener() {
boolean first = true;
@Override
public void onSilenceNotInserted(long timestamp) {
if (first) {
first = false;
// send event only
audioRecordingStarted(ssrc, timestamp);
} else {
// change file and send event
resetRecording(ssrc, timestamp);
}
}
});
desc.silenceEffect = silenceEffect;
AudioLevelEffect audioLevelEffect = new AudioLevelEffect();
audioLevelEffect.setAudioLevelListener(
new SimpleAudioLevelListener() {
@Override
public void audioLevelChanged(int level) {
activeSpeakerDetector.levelChanged(ssrc, level);
}
});
try {
// We add an effect, which will insert "silence" in
// place of lost packets.
track.setCodecChain(new Codec[] {silenceEffect, audioLevelEffect});
} catch (UnsupportedPlugInException upie) {
logger.warn("Failed to insert silence effect: " + upie);
// But do go on, a recording without extra silence is
// better than nothing ;)
}
} else {
// transcode vp8/rtp to vp8 (i.e. depacketize vp8)
if (trackFormat.matches(vp8RtpFormat)) track.setFormat(vp8Format);
else {
logger.error("Unsupported track format: " + trackFormat + " for ssrc=" + desc.ssrc);
// we currently only support vp8
removeReceiveStream(desc, false);
return;
}
}
}
processor.realize();
} else if (ev instanceof RealizeCompleteEvent) {
desc.dataSource = processor.getDataOutput();
long ssrc = desc.ssrc;
boolean audio = desc.format instanceof AudioFormat;
String suffix = audio ? AUDIO_FILENAME_SUFFIX : VIDEO_FILENAME_SUFFIX;
// XXX '\' on windows?
String filename = getNextFilename(path + "/" + ssrc, suffix);
desc.filename = filename;
DataSink dataSink;
if (audio) {
try {
dataSink = Manager.createDataSink(desc.dataSource, new MediaLocator("file:" + filename));
} catch (NoDataSinkException ndse) {
logger.error("Could not create DataSink: " + ndse);
removeReceiveStream(desc, false);
return;
}
} else {
dataSink = new WebmDataSink(filename, desc.dataSource);
}
if (logger.isInfoEnabled())
logger.info(
"Created DataSink ("
+ dataSink
+ ") for SSRC="
+ ssrc
+ ". Output filename: "
+ filename);
try {
dataSink.open();
} catch (IOException e) {
logger.error("Failed to open DataSink (" + dataSink + ") for" + " SSRC=" + ssrc + ": " + e);
removeReceiveStream(desc, false);
return;
}
if (!audio) {
final WebmDataSink webmDataSink = (WebmDataSink) dataSink;
webmDataSink.setSsrc(ssrc);
webmDataSink.setEventHandler(eventHandler);
webmDataSink.setKeyFrameControl(
new KeyFrameControlAdapter() {
@Override
public boolean requestKeyFrame(boolean urgent) {
return requestFIR(webmDataSink);
}
});
}
try {
dataSink.start();
} catch (IOException e) {
logger.error(
"Failed to start DataSink (" + dataSink + ") for" + " SSRC=" + ssrc + ". " + e);
removeReceiveStream(desc, false);
return;
}
if (logger.isInfoEnabled()) logger.info("Started DataSink for SSRC=" + ssrc);
desc.dataSink = dataSink;
processor.start();
} else if (logger.isDebugEnabled()) {
logger.debug(
"Unhandled ControllerEvent from the Processor for ssrc=" + desc.ssrc + ": " + ev);
}
}