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 macroblock (MB) address of the first lost macroblock

    75 	 * @param sliNumber number of lost macroblocks

    76 	 * @param sliPictureId six least significant bits of the codec-specific identifier

    77 	 */

    78 	protected void makeSliceLossIndication(int[] sliFirst, int[] sliNumber, int[] sliPictureId) {

    79 		super.itemCount = 2; //FMT

    80 		this.sliFirst = sliFirst;

    81 		this.sliNumber = sliNumber;

    82 		this.sliPictureId = sliPictureId;

    83 	}

    84 	

    85 	/**

    86 	 * Make this packet a Reference Picture Selection Indication

    87 	 * 

    88 	 * @param bitPadding number of padded bits at end of bitString

    89 	 * @param payloadType RTP payload type for codec

    90 	 * @param bitString RPSI information as natively defined by the video codec

    91 	 */

    92 	protected void makeRefPictureSelIndic(int bitPadding, int payloadType, byte[] bitString) {

    93 		super.itemCount = 3; //FMT

    94 		this.rpsiPadding = bitPadding;

    95 		this.rpsiPayloadType = payloadType;

    96 		this.rpsiBitString = bitString;

    97 	}

    98 	

    99 	/** 

   100 	 * Make this packet an Application specific feedback message

   101 	 * 

   102 	 * @param bitString the original application message

   103 	 */

   104 	protected void makeAppLayerFeedback(byte[] bitString) {

   105 		super.itemCount = 15; //FMT

   106 		this.alfBitString = bitString; 

   107 	}

   108 	

   109 	/**

   110 	 * Constructor that parses a raw packet to retrieve information

   111 	 * 

   112 	 * @param aRawPkt the raw packet to be parsed

   113 	 * @param start the start of the packet, in bytes

   114 	 * @param rtpSession the session on which the callback interface resides

   115 	 */

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

   117 		if(RTPSession.rtpDebugLevel > 8) {

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

   119 		}

   120 		this.rtpSession = rtpSession;

   121 		

   122 		rawPkt = aRawPkt;

   123 

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

   125 			if(RTPSession.rtpDebugLevel > 2) {

   126 				System.out.println(" <-> RtcpPktRTPFB.parseHeaders() etc. problem");

   127 			}

   128 			super.problem = -206;

   129 		} else {

   130 			//FMT = super.itemCount;

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

   132 			

   133 			if(ssrcMediaSource == rtpSession.ssrc) {

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

   135 				

   136 				switch(super.itemCount) {

   137 				case 1: // Picture Loss Indication 

   138 					decPictureLossIndic();

   139 					break; 

   140 				case 2: // Slice Loss Indication

   141 					decSliceLossIndic(aRawPkt, start + 12); 

   142 					break;

   143 				case 3: // Reference Picture Selection Indication 

   144 					decRefPictureSelIndic(aRawPkt, start + 12); 

   145 					break;

   146 				case 15: // Application Layer Feedback Messages

   147 					decAppLayerFB(aRawPkt, start + 12); 

   148 					break;

   149 				default: 

   150 					System.out.println("!!!! RtcpPktPSFB(byte[], int start) unexpected FMT " + super.itemCount);

   151 				}

   152 			} else {

   153 				this.notRelevant = true;

   154 			}

   155 		}

   156 		if(RTPSession.rtpDebugLevel > 8) {

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

   158 		}

   159 	}

   160 	

   161 	/**

   162 	 * Decode Picture Loss indication

   163 	 *

   164 	 */

   165 	private void decPictureLossIndic() {

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

   167 			this.rtpSession.rtcpAVPFIntf.PSFBPktPictureLossReceived(

   168 					super.ssrc);

   169 		}

   170 	}

   171 	

   172 	/**

   173 	 * Decode Slice Loss Indication

   174 	 * 

   175 	 * @param aRawPkt

   176 	 * @param start

   177 	 */

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

   179 		// 13 bit off-boundary numbers? That's rather cruel

   180 		//    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

   181 		//   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   182 		//   |            First        |        Number           | PictureID |

   183 		//   +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   184 				

   185 		int count = super.length - 2;

   186 		

   187 		sliFirst = new int[count];

   188 		sliNumber = new int[count];

   189 		sliPictureId = new int[count];

   190 		

   191 		// Loop over the FCI lines

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

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

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

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

   196 			start += 4;

   197 		}

   198 		

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

   200 			this.rtpSession.rtcpAVPFIntf.PSFBPktSliceLossIndic(

   201 					super.ssrc,

   202 					sliFirst, sliNumber, sliPictureId);

   203 		}

   204 	}

   205 	

   206 	/**

   207 	 * Decode Reference Picture Selection Indication

   208 	 * 

   209 	 * @param aRawPkt

   210 	 * @param start

   211 	 */

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

   213 		//  0                   1                   2                   3

   214 		//  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

   215 		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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

   217 		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

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

   219 		// +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   220 		

   221 		rpsiPadding = aRawPkt[start];

   222 		

   223 		if(rpsiPadding  > 32) {

   224 			System.out.println("!!!! RtcpPktPSFB.decRefPictureSelcIndic paddingBits: " 

   225 					+ rpsiPadding);

   226 		}

   227 		

   228 		rpsiPayloadType = (int) rawPkt[start];

   229 		if(rpsiPayloadType < 0) {

   230 			System.out.println("!!!! RtcpPktPSFB.decRefPictureSelcIndic 8th bit not zero: " 

   231 					+ rpsiPayloadType);

   232 		}

   233 		

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

   235 		System.arraycopy(aRawPkt, start + 2, rpsiBitString, 0, rpsiBitString.length);

   236 		

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

   238 			this.rtpSession.rtcpAVPFIntf.PSFBPktRefPictureSelIndic(

   239 					super.ssrc,

   240 					rpsiPayloadType, rpsiBitString, rpsiPadding);

   241 		}

   242 		

   243 	}

   244 	

   245 	/**

   246 	 * Decode Application specific feedback message

   247 	 * 

   248 	 * @param aRawPkt

   249 	 * @param start

   250 	 */

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

   252 		//Application Message (FCI): variable length

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

   254 		

   255 		alfBitString = new byte[stringLength];

   256 		

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

   258 

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

   260 			this.rtpSession.rtcpAVPFIntf.PSFBPktAppLayerFBReceived(

   261 					super.ssrc, alfBitString);

   262 		}

   263 	}

   264 	

   265 

   266 	

   267 	/**

   268 	 * Encode a Slice Loss Indication

   269 	 */

   270 	private void encSliceLossIndic() {

   271 		byte[] firstBytes;

   272 		byte[] numbBytes;

   273 		byte[] picBytes;

   274 		

   275 		int offset = 8;

   276 		// Loop over the FCI lines

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

   278 			offset = 8 + 8*i;

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

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

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

   282 			

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

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

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

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

   287 		}

   288 	}

   289 	

   290 	/**

   291 	 * Encode a Reference Picture Selection Indication

   292 	 *

   293 	 */

   294 	private void encRefPictureSelIndic() {	

   295 		byte[] someBytes;

   296 		someBytes = StaticProcs.uIntIntToByteWord(rpsiPadding);

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

   298 		someBytes = StaticProcs.uIntIntToByteWord(rpsiPayloadType);

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

   300 		

   301 		System.arraycopy(rpsiBitString, 0, super.rawPkt, 10, rpsiBitString.length);

   302 	}

   303 	

   304 	

   305 	/**

   306 	 * Encode Application Layer Feedback

   307 	 *

   308 	 */

   309 	private void encAppLayerFB() {	

   310 		//Application Message (FCI): variable length

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

   312 	}

   313 	

   314 	/** 

   315 	 * Get the FMT (Feedback Message Type)

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

   317 	 */

   318 	protected int getFMT() {

   319 		return this.itemCount;

   320 	}

   321 	

   322 	/**

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

   324 	 * 

   325 	 * CompRtcpPkt will call this automatically

   326 	 */

   327 	protected void encode() {

   328 		switch(super.itemCount) {

   329 		case 1: // Picture Loss Indication 

   330 			//Nothing to do really

   331 			super.rawPkt = new byte[24];

   332 			break; 

   333 		case 2: // Slice Loss Indication

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

   335 			encSliceLossIndic(); 

   336 			break;

   337 		case 3: // Reference Picture Selection Indication

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

   339 			encRefPictureSelIndic();

   340 			break;

   341 		case 15: // Application Layer Feedback Messages

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

   343 			encAppLayerFB();

   344 			break;

   345 		}

   346 		

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

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

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

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

   351 		

   352 		writeHeaders();

   353 	}

   354 

   355 	/**

   356 	 * Debug purposes only

   357 	 */

   358 	public void debugPrint() {

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

   360 		

   361 		String str;

   362 		switch(super.itemCount) {

   363 		case 1: // Picture Loss Indication 

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

   365 			break; 

   366 		case 2: // Slice Loss Indication

   367 			if(sliFirst != null) {

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

   369 			} else {

   370 				str = "sliFirst[] is null";

   371 			}

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

   373 			break;

   374 		case 3: // Reference Picture Selection Indication

   375 			if(rpsiBitString != null) {

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

   377 			} else {

   378 				str = "rpsiBitString[] is null";

   379 			}

   380 			System.out.println("  FMT: Reference Picture Selection Indication, " 

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

   382 			break;

   383 		case 15: // Application Layer Feedback Messages

   384 			if(alfBitString != null) {

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

   386 			} else {

   387 				str = "alfBitString[] is null";

   388 			}

   389 			System.out.println("  FMT: Application Layer Feedback Messages, " + str);

   390 			break;

   391 		}

   392 

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

   394 	}

   395 }