/**
* Checks whether there are packets with sequence numbers between <tt>firstSeq</tt> and
* <tt>lastSeq</tt> which are *not* stored in <tt>data</tt>.
*
* @return <tt>true</tt> if there are packets with sequence numbers between <tt>firstSeq</tt> and
* <tt>lastSeq</tt> which are *not* stored in <tt>data</tt>.
*/
private boolean haveMissing() {
Set<Long> seqs = data.keySet();
long s = firstSeq;
while (s != lastSeq) {
if (!seqs.contains(s)) return true;
s = (s + 1) % (1 << 16);
}
return false;
}
/**
* Re-initializes the fields which store information about the currently held data. Empties
* <tt>data</tt>.
*/
private void reinit() {
firstSeq = lastSeq = timestamp = -1;
pictureId = -1;
empty = true;
haveEnd = haveStart = false;
frameLength = 0;
Iterator<Map.Entry<Long, Container>> it = data.entrySet().iterator();
Map.Entry<Long, Container> e;
while (it.hasNext()) {
e = it.next();
free.offer(e.getValue());
it.remove();
}
}
/** {@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;
}
}