/** {@inheritDoc} */
@Override
protected int doProcess(Buffer inBuffer, Buffer outBuffer) {
byte[] inData = (byte[]) inBuffer.getData();
int inOffset = inBuffer.getOffset();
if (!VP8PayloadDescriptor.isValid(inData, inOffset)) {
logger.warn("Invalid RTP/VP8 packet discarded.");
outBuffer.setDiscard(true);
return BUFFER_PROCESSED_FAILED; // XXX: FAILED or OK?
}
long inSeq = inBuffer.getSequenceNumber();
long inRtpTimestamp = inBuffer.getRtpTimeStamp();
int inPictureId = VP8PayloadDescriptor.getPictureId(inData, inOffset);
boolean inMarker = (inBuffer.getFlags() & Buffer.FLAG_RTP_MARKER) != 0;
boolean inIsStartOfFrame = VP8PayloadDescriptor.isStartOfFrame(inData, inOffset);
int inLength = inBuffer.getLength();
int inPdSize = VP8PayloadDescriptor.getSize(inData, inOffset);
int inPayloadLength = inLength - inPdSize;
if (empty && lastSentSeq != -1 && seqNumComparator.compare(inSeq, lastSentSeq) != 1) {
if (logger.isInfoEnabled()) logger.info("Discarding old packet (while empty) " + inSeq);
outBuffer.setDiscard(true);
return BUFFER_PROCESSED_OK;
}
if (!empty) {
// if the incoming packet has a different PictureID or timestamp
// than those of the current frame, then it belongs to a different
// frame.
if ((inPictureId != -1 && pictureId != -1 && inPictureId != pictureId)
| (timestamp != -1 && inRtpTimestamp != -1 && inRtpTimestamp != timestamp)) {
if (seqNumComparator.compare(inSeq, firstSeq) != 1) // inSeq <= firstSeq
{
// the packet belongs to a previous frame. discard it
if (logger.isInfoEnabled()) logger.info("Discarding old packet " + inSeq);
outBuffer.setDiscard(true);
return BUFFER_PROCESSED_OK;
} else // inSeq > firstSeq (and also presumably isSeq > lastSeq)
{
// the packet belongs to a subsequent frame (to the one
// currently being held). Drop the current frame.
if (logger.isInfoEnabled())
logger.info(
"Discarding saved packets on arrival of"
+ " a packet for a subsequent frame: "
+ inSeq);
// TODO: this would be the place to complain about the
// not-well-received PictureID by sending a RTCP SLI or NACK.
reinit();
}
}
}
// a whole frame in a single packet. avoid the extra copy to
// this.data and output it immediately.
if (empty && inMarker && inIsStartOfFrame) {
byte[] outData = validateByteArraySize(outBuffer, inPayloadLength, false);
System.arraycopy(inData, inOffset + inPdSize, outData, 0, inPayloadLength);
outBuffer.setOffset(0);
outBuffer.setLength(inPayloadLength);
outBuffer.setRtpTimeStamp(inBuffer.getRtpTimeStamp());
if (TRACE) logger.trace("Out PictureID=" + inPictureId);
lastSentSeq = inSeq;
return BUFFER_PROCESSED_OK;
}
// add to this.data
Container container = free.poll();
if (container == null) container = new Container();
if (container.buf == null || container.buf.length < inPayloadLength)
container.buf = new byte[inPayloadLength];
if (data.get(inSeq) != null) {
if (logger.isInfoEnabled())
logger.info("(Probable) duplicate packet detected, discarding " + inSeq);
outBuffer.setDiscard(true);
return BUFFER_PROCESSED_OK;
}
System.arraycopy(inData, inOffset + inPdSize, container.buf, 0, inPayloadLength);
container.len = inPayloadLength;
data.put(inSeq, container);
// update fields
frameLength += inPayloadLength;
if (firstSeq == -1 || (seqNumComparator.compare(firstSeq, inSeq) == 1)) firstSeq = inSeq;
if (lastSeq == -1 || (seqNumComparator.compare(inSeq, lastSeq) == 1)) lastSeq = inSeq;
if (empty) {
// the first received packet for the current frame was just added
empty = false;
timestamp = inRtpTimestamp;
pictureId = inPictureId;
}
if (inMarker) haveEnd = true;
if (inIsStartOfFrame) haveStart = true;
// check if we have a full frame
if (frameComplete()) {
byte[] outData = validateByteArraySize(outBuffer, frameLength, false);
int ptr = 0;
Container b;
for (Map.Entry<Long, Container> entry : data.entrySet()) {
b = entry.getValue();
System.arraycopy(b.buf, 0, outData, ptr, b.len);
ptr += b.len;
}
outBuffer.setOffset(0);
outBuffer.setLength(frameLength);
outBuffer.setRtpTimeStamp(inBuffer.getRtpTimeStamp());
if (TRACE) logger.trace("Out PictureID=" + inPictureId);
lastSentSeq = lastSeq;
// prepare for the next frame
reinit();
return BUFFER_PROCESSED_OK;
} else {
// frame not complete yet
outBuffer.setDiscard(true);
return OUTPUT_BUFFER_NOT_FILLED;
}
}
/**
* Notifies this instance that a <tt>DatagramPacket</tt> packet received on the data
* <tt>DatagramSocket</tt> of this <tt>Channel</tt> has been accepted for further processing
* within Jitsi Videobridge.
*
* @param pkt the accepted <tt>RawPacket</tt>.
*/
public void accepted(RawPacket pkt) {
// With native simulcast we don't have a notification when a stream
// has started/stopped. The simulcast manager implements a timeout
// for the high quality stream and it needs to be notified when
// the channel has accepted a datagram packet for the timeout to
// function correctly.
if (!hasLayers() || pkt == null) {
return;
}
// Find the layer that corresponds to this packet.
int acceptedSSRC = pkt.getSSRC();
SimulcastLayer[] layers = getSimulcastLayers();
SimulcastLayer acceptedLayer = null;
for (SimulcastLayer layer : layers) {
// We only care about the primary SSRC and not the RTX ssrc (or
// future FEC ssrc).
if ((int) layer.getPrimarySSRC() == acceptedSSRC) {
acceptedLayer = layer;
break;
}
}
// If this is not an RTP packet or if we can't find an accepted
// layer, log and return as it makes no sense to continue in this
// situation.
if (acceptedLayer == null) {
return;
}
// There are sequences of packets with increasing timestamps but without
// the marker bit set. Supposedly, they are probes to detect whether the
// bandwidth may increase. We think that they should cause neither the
// start nor the stop of any SimulcastLayer.
// XXX There's RawPacket#getPayloadLength() but the implementation
// includes pkt.paddingSize at the time of this writing and we do not
// know whether that's going to stay that way.
int pktPayloadLength = pkt.getLength() - pkt.getHeaderLength();
int pktPaddingSize = pkt.getPaddingSize();
if (pktPayloadLength <= pktPaddingSize) {
if (logger.isTraceEnabled()) {
logger.trace(
"pkt.payloadLength= "
+ pktPayloadLength
+ " <= pkt.paddingSize= "
+ pktPaddingSize
+ "("
+ pkt.getSequenceNumber()
+ ")");
}
return;
}
// NOTE(gp) we expect the base layer to be always on, so we never touch
// it or starve it.
// XXX Refer to the implementation of
// SimulcastLayer#touch(boolean, RawPacket) for an explanation of why we
// chose to use a return value.
boolean frameStarted = acceptedLayer.touch(pkt);
if (frameStarted) simulcastLayerFrameStarted(acceptedLayer, pkt, layers);
}
