1 /**

     2  * Java RTP Library (jlibrtp)

     3  * Copyright (C) 2006 Arne Kepp

     4  * 

     5  * This library is free software; you can redistribute it and/or

     6  * modify it under the terms of the GNU Lesser General Public

     7  * License as published by the Free Software Foundation; either

     8  * version 2.1 of the License, or (at your option) any later version.

     9  *

    10  * This library is distributed in the hope that it will be useful,

    11  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    13  * Lesser General Public License for more details.

    14  * 

    15  * You should have received a copy of the GNU Lesser General Public

    16  * License along with this library; if not, write to the Free Software

    17  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

    18  */

    19 package jlibrtp;

    20 

    21 /**

    22  * RTCP packets for Payload-Specific Feedback Messages

    23  * 

    24  * @author Arne Kepp

    25  */

    26 public class RtcpPktPSFB extends RtcpPkt {

    27 	/** If this packet was for a different SSRC */

    28 	protected boolean notRelevant = false;

    29 	/** Parent RTP Session */

    30 	private RTPSession rtpSession;

    31 	/** SSRC we are sending feeback to */

    32 	protected long ssrcMediaSource = -1;

    33 

    34 	/** SLI macroblock (MB) address of the first lost macroblock number */

    35 	protected int[] sliFirst;

    36 	/** SLI number of lost macroblocks */

    37 	protected int[] sliNumber;

    38 	/** SLI six least significant bits of the codec-specific identifier */

    39 	protected int[] sliPictureId;

    40 

    41 	// Picture loss indication

    42 	/** RPSI number of padded bits at end of bitString */

    43 	protected int rpsiPadding = -1;

    44 	/** RPSI payloadType RTP payload type */

    45 	protected int rpsiPayloadType = -1;

    46 	/** RPSI information as natively defined by the video codec */

    47 	protected byte[] rpsiBitString;

    48 

    49 	/** Application Layer Feedback Message */

    50 	protected byte[] alfBitString;

    51 

    52 	/**

    53 	 * Generic constructor, then call make<something>

    54 	 * 

    55 	 * @param ssrcPacketSender

    56 	 * @param ssrcMediaSource

    57 	 */

    58 	protected RtcpPktPSFB(long ssrcPacketSender, long ssrcMediaSource) {

    59 		super.ssrc = ssrcPacketSender;

    60 		this.ssrcMediaSource = ssrcMediaSource;

    61 		super.packetType = 206; // PSFB

    62 	}

    63 

    64 	/**

    65 	 * Make this packet a Picture loss indication

    66 	 */

    67 	protected void makePictureLossIndication() {

    68 		super.itemCount = 1; // FMT

    69 	}

    70 

    71 	/**

    72 	 * Make this packet a Slice Loss Indication

    73 	 * 

    74 	 * @param sliFirst

    75 	 *            macroblock (MB) address of the first lost macroblock

    76 	 * @param sliNumber

    77 	 *            number of lost macroblocks

    78 	 * @param sliPictureId

    79 	 *            six least significant bits of the codec-specific identifier

    80 	 */

    81 	protected void makeSliceLossIndication(int[] sliFirst, int[] sliNumber,

    82 			int[] sliPictureId) {

    83 		super.itemCount = 2; // FMT

    84 		this.sliFirst = sliFirst;

    85 		this.sliNumber = sliNumber;

    86 		this.sliPictureId = sliPictureId;

    87 	}

    88 

    89 	/**

    90 	 * Make this packet a Reference Picture Selection Indication

    91 	 * 

    92 	 * @param bitPadding

    93 	 *            number of padded bits at end of bitString

    94 	 * @param payloadType

    95 	 *            RTP payload type for codec

    96 	 * @param bitString

    97 	 *            RPSI information as natively defined by the video codec

    98 	 */

    99 	protected void makeRefPictureSelIndic(int bitPadding, int payloadType,

   100 			byte[] bitString) {

   101 		super.itemCount = 3; // FMT

   102 		this.rpsiPadding = bitPadding;

   103 		this.rpsiPayloadType = payloadType;

   104 		this.rpsiBitString = bitString;

   105 	}

   106 

   107 	/**

   108 	 * Make this packet an Application specific feedback message

   109 	 * 

   110 	 * @param bitString

   111 	 *            the original application message

   112 	 */

   113 	protected void makeAppLayerFeedback(byte[] bitString) {

   114 		super.itemCount = 15; // FMT

   115 		this.alfBitString = bitString;

   116 	}

   117 

   118 	/**

   119 	 * Constructor that parses a raw packet to retrieve information

   120 	 * 

   121 	 * @param aRawPkt

   122 	 *            the raw packet to be parsed

   123 	 * @param start

   124 	 *            the start of the packet, in bytes

   125 	 * @param rtpSession

   126 	 *            the session on which the callback interface resides

   127 	 */

   128 	protected RtcpPktPSFB(byte[] aRawPkt, int start, RTPSession rtpSession) {

   129 		if (RTPSession.rtpDebugLevel > 8) {

   130 			System.out.println("  -> RtcpPktPSFB(byte[], int start)");

   131 		}

   132 		this.rtpSession = rtpSession;

   133 

   134 		rawPkt = aRawPkt;

   135 

   136 		if (!super.parseHeaders(start) || packetType != 206 || super.length < 2) {

   137 			if (RTPSession.rtpDebugLevel > 2) {

   138 				System.out

   139 						.println(" <-> RtcpPktRTPFB.parseHeaders() etc. problem");

   140 			}

   141 			super.problem = -206;

   142 		} else {

   143 			// FMT = super.itemCount;

   144 			ssrcMediaSource = StaticProcs.bytesToUIntLong(aRawPkt, 8 + start);

   145 

   146 			if (ssrcMediaSource == rtpSession.ssrc) {

   147 				super.ssrc = StaticProcs.bytesToUIntLong(aRawPkt, 4 + start);

   148 

   149 				switch (super.itemCount) {

   150 				case 1: // Picture Loss Indication

   151 					decPictureLossIndic();

   152 					break;

   153 				case 2: // Slice Loss Indication

   154 					decSliceLossIndic(aRawPkt, start + 12);

   155 					break;

   156 				case 3: // Reference Picture Selection Indication

   157 					decRefPictureSelIndic(aRawPkt, start + 12);

   158 					break;

   159 				case 15: // Application Layer Feedback Messages

   160 					decAppLayerFB(aRawPkt, start + 12);

   161 					break;

   162 				default:

   163 					System.out

   164 							.println("!!!! RtcpPktPSFB(byte[], int start) unexpected FMT "

   165 									+ super.itemCount);

   166 				}

   167 			} else {

   168 				this.notRelevant = true;

   169 			}

   170 		}

   171 		if (RTPSession.rtpDebugLevel > 8) {

   172 			System.out.println("  <- RtcpPktPSFB()");

   173 		}

   174 	}

   175 

   176 	/**

   177 	 * Decode Picture Loss indication

   178 	 * 

   179 	 */

   180 	private void decPictureLossIndic() {

   181 		if (this.rtpSession.rtcpAVPFIntf != null) {

   182 			this.rtpSession.rtcpAVPFIntf.PSFBPktPictureLossReceived(super.ssrc);

   183 		}

   184 	}

   185 

   186 	/**

   187 	 * Decode Slice Loss Indication

   188 	 * 

   189 	 * @param aRawPkt

   190 	 * @param start

   191 	 */

   192 	private void decSliceLossIndic(byte[] aRawPkt, int start) {

   193 		// 13 bit off-boundary numbers? That's rather cruel

   194 		// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1

   195 		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   196 		// | First | Number | PictureID |

   197 		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   198 

   199 		int count = super.length - 2;

   200 

   201 		sliFirst = new int[count];

   202 		sliNumber = new int[count];

   203 		sliPictureId = new int[count];

   204 

   205 		// Loop over the FCI lines

   206 		for (int i = 0; i < count; i++) {

   207 			sliFirst[i] = StaticProcs.bytesToUIntInt(aRawPkt, start) >> 3;

   208 			sliNumber[i] = (int) (StaticProcs.bytesToUIntInt(aRawPkt, start) & 0x0007FFC0) >> 6;

   209 			sliPictureId[i] = (StaticProcs.bytesToUIntInt(aRawPkt, start + 2) & 0x003F);

   210 			start += 4;

   211 		}

   212 

   213 		if (this.rtpSession.rtcpAVPFIntf != null) {

   214 			this.rtpSession.rtcpAVPFIntf.PSFBPktSliceLossIndic(super.ssrc,

   215 					sliFirst, sliNumber, sliPictureId);

   216 		}

   217 	}

   218 

   219 	/**

   220 	 * Decode Reference Picture Selection Indication

   221 	 * 

   222 	 * @param aRawPkt

   223 	 * @param start

   224 	 */

   225 	private void decRefPictureSelIndic(byte[] aRawPkt, int start) {

   226 		// 0 1 2 3

   227 		// 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1

   228 		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   229 		// | PB |0| Payload Type| Native RPSI bit string |

   230 		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   231 		// | defined per codec ... | Padding (0) |

   232 		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   233 

   234 		rpsiPadding = aRawPkt[start];

   235 

   236 		if (rpsiPadding > 32) {

   237 			System.out

   238 					.println("!!!! RtcpPktPSFB.decRefPictureSelcIndic paddingBits: "

   239 							+ rpsiPadding);

   240 		}

   241 

   242 		rpsiPayloadType = (int) rawPkt[start];

   243 		if (rpsiPayloadType < 0) {

   244 			System.out

   245 					.println("!!!! RtcpPktPSFB.decRefPictureSelcIndic 8th bit not zero: "

   246 							+ rpsiPayloadType);

   247 		}

   248 

   249 		rpsiBitString = new byte[(super.length - 2) * 4 - 2];

   250 		System.arraycopy(aRawPkt, start + 2, rpsiBitString, 0,

   251 				rpsiBitString.length);

   252 

   253 		if (this.rtpSession.rtcpAVPFIntf != null) {

   254 			this.rtpSession.rtcpAVPFIntf.PSFBPktRefPictureSelIndic(super.ssrc,

   255 					rpsiPayloadType, rpsiBitString, rpsiPadding);

   256 		}

   257 

   258 	}

   259 

   260 	/**

   261 	 * Decode Application specific feedback message

   262 	 * 

   263 	 * @param aRawPkt

   264 	 * @param start

   265 	 */

   266 	private void decAppLayerFB(byte[] aRawPkt, int start) {

   267 		// Application Message (FCI): variable length

   268 		int stringLength = (super.length - 2) * 4;

   269 

   270 		alfBitString = new byte[stringLength];

   271 

   272 		System.arraycopy(aRawPkt, start, alfBitString, 0, stringLength);

   273 

   274 		if (this.rtpSession.rtcpAVPFIntf != null) {

   275 			this.rtpSession.rtcpAVPFIntf.PSFBPktAppLayerFBReceived(super.ssrc,

   276 					alfBitString);

   277 		}

   278 	}

   279 

   280 	/**

   281 	 * Encode a Slice Loss Indication

   282 	 */

   283 	private void encSliceLossIndic() {

   284 		byte[] firstBytes;

   285 		byte[] numbBytes;

   286 		byte[] picBytes;

   287 

   288 		int offset = 8;

   289 		// Loop over the FCI lines

   290 		for (int i = 0; i < sliFirst.length; i++) {

   291 			offset = 8 + 8 * i;

   292 			firstBytes = StaticProcs.uIntLongToByteWord(sliFirst[i] << 3);

   293 			numbBytes = StaticProcs.uIntLongToByteWord(sliNumber[i] << 2);

   294 			picBytes = StaticProcs.uIntIntToByteWord(sliPictureId[i]);

   295 

   296 			super.rawPkt[offset] = firstBytes[2];

   297 			super.rawPkt[offset + 1] = (byte) (firstBytes[3] | numbBytes[2]);

   298 			super.rawPkt[offset + 2] = numbBytes[3];

   299 			super.rawPkt[offset + 3] = (byte) (numbBytes[3] | picBytes[1]);

   300 		}

   301 	}

   302 

   303 	/**

   304 	 * Encode a Reference Picture Selection Indication

   305 	 * 

   306 	 */

   307 	private void encRefPictureSelIndic() {

   308 		byte[] someBytes;

   309 		someBytes = StaticProcs.uIntIntToByteWord(rpsiPadding);

   310 		super.rawPkt[8] = someBytes[1];

   311 		someBytes = StaticProcs.uIntIntToByteWord(rpsiPayloadType);

   312 		super.rawPkt[9] = someBytes[1];

   313 

   314 		System.arraycopy(rpsiBitString, 0, super.rawPkt, 10,

   315 				rpsiBitString.length);

   316 	}

   317 

   318 	/**

   319 	 * Encode Application Layer Feedback

   320 	 * 

   321 	 */

   322 	private void encAppLayerFB() {

   323 		// Application Message (FCI): variable length

   324 		System.arraycopy(alfBitString, 0, super.rawPkt, 8, alfBitString.length);

   325 	}

   326 

   327 	/**

   328 	 * Get the FMT (Feedback Message Type)

   329 	 * 

   330 	 * @return value stored in .itemcount, same field

   331 	 */

   332 	protected int getFMT() {

   333 		return this.itemCount;

   334 	}

   335 

   336 	/**

   337 	 * Encode the packet into a byte[], saved in .rawPkt

   338 	 * 

   339 	 * CompRtcpPkt will call this automatically

   340 	 */

   341 	protected void encode() {

   342 		switch (super.itemCount) {

   343 		case 1: // Picture Loss Indication

   344 			// Nothing to do really

   345 			super.rawPkt = new byte[24];

   346 			break;

   347 		case 2: // Slice Loss Indication

   348 			super.rawPkt = new byte[24 + 4 * this.sliFirst.length];

   349 			encSliceLossIndic();

   350 			break;

   351 		case 3: // Reference Picture Selection Indication

   352 			super.rawPkt = new byte[24 + 2 + this.rpsiBitString.length / 4];

   353 			encRefPictureSelIndic();

   354 			break;

   355 		case 15: // Application Layer Feedback Messages

   356 			super.rawPkt = new byte[24 + this.alfBitString.length / 4];

   357 			encAppLayerFB();

   358 			break;

   359 		}

   360 

   361 		byte[] someBytes = StaticProcs.uIntLongToByteWord(super.ssrc);

   362 		System.arraycopy(someBytes, 0, super.rawPkt, 4, 4);

   363 		someBytes = StaticProcs.uIntLongToByteWord(this.ssrcMediaSource);

   364 		System.arraycopy(someBytes, 0, super.rawPkt, 8, 4);

   365 

   366 		writeHeaders();

   367 	}

   368 

   369 	/**

   370 	 * Debug purposes only

   371 	 */

   372 	public void debugPrint() {

   373 		System.out.println("->RtcpPktPSFB.debugPrint() ");

   374 

   375 		String str;

   376 		switch (super.itemCount) {

   377 		case 1: // Picture Loss Indication

   378 			System.out.println("  FMT: Picture Loss Indication");

   379 			break;

   380 		case 2: // Slice Loss Indication

   381 			if (sliFirst != null) {

   382 				str = "sliFirst[].length: " + sliFirst.length;

   383 			} else {

   384 				str = "sliFirst[] is null";

   385 			}

   386 			System.out.println("  FMT: Slice Loss Indication, " + str);

   387 			break;

   388 		case 3: // Reference Picture Selection Indication

   389 			if (rpsiBitString != null) {

   390 				str = "rpsiBitString[].length: " + rpsiBitString.length;

   391 			} else {

   392 				str = "rpsiBitString[] is null";

   393 			}

   394 			System.out

   395 					.println("  FMT: Reference Picture Selection Indication, "

   396 							+ str + " payloadType: " + this.rpsiPayloadType);

   397 			break;

   398 		case 15: // Application Layer Feedback Messages

   399 			if (alfBitString != null) {

   400 				str = "alfBitString[].length: " + alfBitString.length;

   401 			} else {

   402 				str = "alfBitString[] is null";

   403 			}

   404 			System.out.println("  FMT: Application Layer Feedback Messages, "

   405 					+ str);

   406 			break;

   407 		}

   408 

   409 		System.out.println("<-RtcpPktPSFB.debugPrint() ");

   410 	}

   411 }