| 1 | /********** |
| 2 | This library is free software; you can redistribute it and/or modify it under |
| 3 | the terms of the GNU Lesser General Public License as published by the |
| 4 | Free Software Foundation; either version 3 of the License, or (at your |
| 5 | option) any later version. (See <http://www.gnu.org/copyleft/lesser.html>.) |
| 6 | |
| 7 | This library is distributed in the hope that it will be useful, but WITHOUT |
| 8 | ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS |
| 9 | FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for |
| 10 | more details. |
| 11 | |
| 12 | You should have received a copy of the GNU Lesser General Public License |
| 13 | along with this library; if not, write to the Free Software Foundation, Inc., |
| 14 | 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA |
| 15 | **********/ |
| 16 | // "liveMedia" |
| 17 | // Copyright (c) 1996-2020 Live Networks, Inc. All rights reserved. |
| 18 | // AMR Audio RTP Sources (RFC 4867) |
| 19 | // Implementation |
| 20 | |
| 21 | #include "AMRAudioRTPSource.hh" |
| 22 | #include "MultiFramedRTPSource.hh" |
| 23 | #include "BitVector.hh" |
| 24 | #include <string.h> |
| 25 | #include <stdlib.h> |
| 26 | |
| 27 | // This source is implemented internally by two separate sources: |
| 28 | // (i) a RTP source for the raw (and possibly interleaved) AMR frames, and |
| 29 | // (ii) a deinterleaving filter that reads from this. |
| 30 | // Define these two new classes here: |
| 31 | |
| 32 | class RawAMRRTPSource: public MultiFramedRTPSource { |
| 33 | public: |
| 34 | static RawAMRRTPSource* |
| 35 | createNew(UsageEnvironment& env, |
| 36 | Groupsock* RTPgs, unsigned char rtpPayloadFormat, |
| 37 | Boolean isWideband, Boolean isOctetAligned, |
| 38 | Boolean isInterleaved, Boolean CRCsArePresent); |
| 39 | |
| 40 | Boolean isWideband() const { return fIsWideband; } |
| 41 | unsigned char ILL() const { return fILL; } |
| 42 | unsigned char ILP() const { return fILP; } |
| 43 | unsigned TOCSize() const { return fTOCSize; } // total # of frames in the last pkt |
| 44 | unsigned char* TOC() const { return fTOC; } // FT+Q value for each TOC entry |
| 45 | unsigned& frameIndex() { return fFrameIndex; } // index of frame-block within pkt |
| 46 | Boolean& isSynchronized() { return fIsSynchronized; } |
| 47 | |
| 48 | private: |
| 49 | RawAMRRTPSource(UsageEnvironment& env, Groupsock* RTPgs, |
| 50 | unsigned char rtpPayloadFormat, |
| 51 | Boolean isWideband, Boolean isOctetAligned, |
| 52 | Boolean isInterleaved, Boolean CRCsArePresent); |
| 53 | // called only by createNew() |
| 54 | |
| 55 | virtual ~RawAMRRTPSource(); |
| 56 | |
| 57 | private: |
| 58 | // redefined virtual functions: |
| 59 | virtual Boolean hasBeenSynchronizedUsingRTCP(); |
| 60 | |
| 61 | virtual Boolean processSpecialHeader(BufferedPacket* packet, |
| 62 | unsigned& ); |
| 63 | virtual char const* MIMEtype() const; |
| 64 | |
| 65 | private: |
| 66 | Boolean fIsWideband, fIsOctetAligned, fIsInterleaved, fCRCsArePresent; |
| 67 | unsigned char fILL, fILP; |
| 68 | unsigned fTOCSize; |
| 69 | unsigned char* fTOC; |
| 70 | unsigned fFrameIndex; |
| 71 | Boolean fIsSynchronized; |
| 72 | }; |
| 73 | |
| 74 | class AMRDeinterleaver: public AMRAudioSource { |
| 75 | public: |
| 76 | static AMRDeinterleaver* |
| 77 | createNew(UsageEnvironment& env, |
| 78 | Boolean isWideband, unsigned numChannels, unsigned maxInterleaveGroupSize, |
| 79 | RawAMRRTPSource* inputSource); |
| 80 | |
| 81 | private: |
| 82 | AMRDeinterleaver(UsageEnvironment& env, |
| 83 | Boolean isWideband, unsigned numChannels, |
| 84 | unsigned maxInterleaveGroupSize, RawAMRRTPSource* inputSource); |
| 85 | // called only by "createNew()" |
| 86 | |
| 87 | virtual ~AMRDeinterleaver(); |
| 88 | |
| 89 | static void afterGettingFrame(void* clientData, unsigned frameSize, |
| 90 | unsigned numTruncatedBytes, |
| 91 | struct timeval presentationTime, |
| 92 | unsigned durationInMicroseconds); |
| 93 | void afterGettingFrame1(unsigned frameSize, struct timeval presentationTime); |
| 94 | |
| 95 | private: |
| 96 | // Redefined virtual functions: |
| 97 | void doGetNextFrame(); |
| 98 | virtual void doStopGettingFrames(); |
| 99 | |
| 100 | private: |
| 101 | RawAMRRTPSource* fInputSource; |
| 102 | class AMRDeinterleavingBuffer* fDeinterleavingBuffer; |
| 103 | Boolean fNeedAFrame; |
| 104 | }; |
| 105 | |
| 106 | |
| 107 | ////////// AMRAudioRTPSource implementation ////////// |
| 108 | |
| 109 | #define MAX_NUM_CHANNELS 20 // far larger than ever expected... |
| 110 | #define MAX_INTERLEAVING_GROUP_SIZE 1000 // far larger than ever expected... |
| 111 | |
| 112 | AMRAudioSource* |
| 113 | AMRAudioRTPSource::createNew(UsageEnvironment& env, |
| 114 | Groupsock* RTPgs, |
| 115 | RTPSource*& resultRTPSource, |
| 116 | unsigned char rtpPayloadFormat, |
| 117 | Boolean isWideband, |
| 118 | unsigned numChannels, |
| 119 | Boolean isOctetAligned, |
| 120 | unsigned interleaving, |
| 121 | Boolean robustSortingOrder, |
| 122 | Boolean CRCsArePresent) { |
| 123 | // Perform sanity checks on the input parameters: |
| 124 | if (robustSortingOrder) { |
| 125 | env << "AMRAudioRTPSource::createNew(): 'Robust sorting order' was specified, but we don't yet support this!\n" ; |
| 126 | return NULL; |
| 127 | } else if (numChannels > MAX_NUM_CHANNELS) { |
| 128 | env << "AMRAudioRTPSource::createNew(): The \"number of channels\" parameter (" |
| 129 | << numChannels << ") is much too large!\n" ; |
| 130 | return NULL; |
| 131 | } else if (interleaving > MAX_INTERLEAVING_GROUP_SIZE) { |
| 132 | env << "AMRAudioRTPSource::createNew(): The \"interleaving\" parameter (" |
| 133 | << interleaving << ") is much too large!\n" ; |
| 134 | return NULL; |
| 135 | } |
| 136 | |
| 137 | // 'Bandwidth-efficient mode' precludes some other options: |
| 138 | if (!isOctetAligned) { |
| 139 | if (interleaving > 0 || robustSortingOrder || CRCsArePresent) { |
| 140 | env << "AMRAudioRTPSource::createNew(): 'Bandwidth-efficient mode' was specified, along with interleaving, 'robust sorting order', and/or CRCs, so we assume 'octet-aligned mode' instead.\n" ; |
| 141 | isOctetAligned = True; |
| 142 | } |
| 143 | } |
| 144 | |
| 145 | Boolean isInterleaved; |
| 146 | unsigned maxInterleaveGroupSize; // in frames (not frame-blocks) |
| 147 | if (interleaving > 0) { |
| 148 | isInterleaved = True; |
| 149 | maxInterleaveGroupSize = interleaving*numChannels; |
| 150 | } else { |
| 151 | isInterleaved = False; |
| 152 | maxInterleaveGroupSize = numChannels; |
| 153 | } |
| 154 | |
| 155 | RawAMRRTPSource* rawRTPSource; |
| 156 | resultRTPSource = rawRTPSource |
| 157 | = RawAMRRTPSource::createNew(env, RTPgs, rtpPayloadFormat, |
| 158 | isWideband, isOctetAligned, |
| 159 | isInterleaved, CRCsArePresent); |
| 160 | if (resultRTPSource == NULL) return NULL; |
| 161 | |
| 162 | AMRDeinterleaver* deinterleaver |
| 163 | = AMRDeinterleaver::createNew(env, isWideband, numChannels, |
| 164 | maxInterleaveGroupSize, rawRTPSource); |
| 165 | if (deinterleaver == NULL) { |
| 166 | Medium::close(resultRTPSource); |
| 167 | resultRTPSource = NULL; |
| 168 | } |
| 169 | |
| 170 | return deinterleaver; |
| 171 | } |
| 172 | |
| 173 | |
| 174 | ////////// AMRBufferedPacket and AMRBufferedPacketFactory ////////// |
| 175 | |
| 176 | // A subclass of BufferedPacket, used to separate out AMR frames. |
| 177 | |
| 178 | class AMRBufferedPacket: public BufferedPacket { |
| 179 | public: |
| 180 | AMRBufferedPacket(RawAMRRTPSource& ourSource); |
| 181 | virtual ~AMRBufferedPacket(); |
| 182 | |
| 183 | private: // redefined virtual functions |
| 184 | virtual unsigned nextEnclosedFrameSize(unsigned char*& framePtr, |
| 185 | unsigned dataSize); |
| 186 | private: |
| 187 | RawAMRRTPSource& fOurSource; |
| 188 | }; |
| 189 | |
| 190 | class AMRBufferedPacketFactory: public BufferedPacketFactory { |
| 191 | private: // redefined virtual functions |
| 192 | virtual BufferedPacket* createNewPacket(MultiFramedRTPSource* ourSource); |
| 193 | }; |
| 194 | |
| 195 | |
| 196 | ///////// RawAMRRTPSource implementation //////// |
| 197 | |
| 198 | RawAMRRTPSource* |
| 199 | RawAMRRTPSource::createNew(UsageEnvironment& env, Groupsock* RTPgs, |
| 200 | unsigned char rtpPayloadFormat, |
| 201 | Boolean isWideband, Boolean isOctetAligned, |
| 202 | Boolean isInterleaved, Boolean CRCsArePresent) { |
| 203 | return new RawAMRRTPSource(env, RTPgs, rtpPayloadFormat, |
| 204 | isWideband, isOctetAligned, |
| 205 | isInterleaved, CRCsArePresent); |
| 206 | } |
| 207 | |
| 208 | RawAMRRTPSource |
| 209 | ::RawAMRRTPSource(UsageEnvironment& env, |
| 210 | Groupsock* RTPgs, unsigned char rtpPayloadFormat, |
| 211 | Boolean isWideband, Boolean isOctetAligned, |
| 212 | Boolean isInterleaved, Boolean CRCsArePresent) |
| 213 | : MultiFramedRTPSource(env, RTPgs, rtpPayloadFormat, |
| 214 | isWideband ? 16000 : 8000, |
| 215 | new AMRBufferedPacketFactory), |
| 216 | fIsWideband(isWideband), fIsOctetAligned(isOctetAligned), |
| 217 | fIsInterleaved(isInterleaved), fCRCsArePresent(CRCsArePresent), |
| 218 | fILL(0), fILP(0), fTOCSize(0), fTOC(NULL), fFrameIndex(0), fIsSynchronized(False) { |
| 219 | } |
| 220 | |
| 221 | RawAMRRTPSource::~RawAMRRTPSource() { |
| 222 | delete[] fTOC; |
| 223 | } |
| 224 | |
| 225 | #define FT_SPEECH_LOST 14 |
| 226 | #define FT_NO_DATA 15 |
| 227 | |
| 228 | static void unpackBandwidthEfficientData(BufferedPacket* packet, |
| 229 | Boolean isWideband); // forward |
| 230 | |
| 231 | Boolean RawAMRRTPSource |
| 232 | ::(BufferedPacket* packet, |
| 233 | unsigned& ) { |
| 234 | // If the data is 'bandwidth-efficient', first unpack it so that it's |
| 235 | // 'octet-aligned': |
| 236 | if (!fIsOctetAligned) unpackBandwidthEfficientData(packet, fIsWideband); |
| 237 | |
| 238 | unsigned char* = packet->data(); |
| 239 | unsigned packetSize = packet->dataSize(); |
| 240 | |
| 241 | // There's at least a 1-byte header, containing the CMR: |
| 242 | if (packetSize < 1) return False; |
| 243 | resultSpecialHeaderSize = 1; |
| 244 | |
| 245 | if (fIsInterleaved) { |
| 246 | // There's an extra byte, containing the interleave parameters: |
| 247 | if (packetSize < 2) return False; |
| 248 | |
| 249 | // Get the interleaving parameters, and check them for validity: |
| 250 | unsigned char const secondByte = headerStart[1]; |
| 251 | fILL = (secondByte&0xF0)>>4; |
| 252 | fILP = secondByte&0x0F; |
| 253 | if (fILP > fILL) return False; // invalid |
| 254 | ++resultSpecialHeaderSize; |
| 255 | } |
| 256 | #ifdef DEBUG |
| 257 | fprintf(stderr, "packetSize: %d, ILL: %d, ILP: %d\n" , packetSize, fILL, fILP); |
| 258 | #endif |
| 259 | fFrameIndex = 0; // initially |
| 260 | |
| 261 | // Next, there's a "Payload Table of Contents" (one byte per entry): |
| 262 | unsigned numFramesPresent = 0, numNonEmptyFramesPresent = 0; |
| 263 | unsigned tocStartIndex = resultSpecialHeaderSize; |
| 264 | Boolean F; |
| 265 | do { |
| 266 | if (resultSpecialHeaderSize >= packetSize) return False; |
| 267 | unsigned char const tocByte = headerStart[resultSpecialHeaderSize++]; |
| 268 | F = (tocByte&0x80) != 0; |
| 269 | unsigned char const FT = (tocByte&0x78) >> 3; |
| 270 | #ifdef DEBUG |
| 271 | unsigned char Q = (tocByte&0x04)>>2; |
| 272 | fprintf(stderr, "\tTOC entry: F %d, FT %d, Q %d\n" , F, FT, Q); |
| 273 | #endif |
| 274 | ++numFramesPresent; |
| 275 | if (FT != FT_SPEECH_LOST && FT != FT_NO_DATA) ++numNonEmptyFramesPresent; |
| 276 | } while (F); |
| 277 | #ifdef DEBUG |
| 278 | fprintf(stderr, "TOC contains %d entries (%d non-empty)\n" , numFramesPresent, numNonEmptyFramesPresent); |
| 279 | #endif |
| 280 | |
| 281 | // Now that we know the size of the TOC, fill in our copy: |
| 282 | if (numFramesPresent > fTOCSize) { |
| 283 | delete[] fTOC; |
| 284 | fTOC = new unsigned char[numFramesPresent]; |
| 285 | } |
| 286 | fTOCSize = numFramesPresent; |
| 287 | for (unsigned i = 0; i < fTOCSize; ++i) { |
| 288 | unsigned char const tocByte = headerStart[tocStartIndex + i]; |
| 289 | fTOC[i] = tocByte&0x7C; // clear everything except the F and Q fields |
| 290 | } |
| 291 | |
| 292 | if (fCRCsArePresent) { |
| 293 | // 'numNonEmptyFramesPresent' CRC bytes will follow. |
| 294 | // Note: we currently don't check the CRCs for validity ##### |
| 295 | resultSpecialHeaderSize += numNonEmptyFramesPresent; |
| 296 | #ifdef DEBUG |
| 297 | fprintf(stderr, "Ignoring %d following CRC bytes\n" , numNonEmptyFramesPresent); |
| 298 | #endif |
| 299 | if (resultSpecialHeaderSize > packetSize) return False; |
| 300 | } |
| 301 | #ifdef DEBUG |
| 302 | fprintf(stderr, "Total special header size: %d\n" , resultSpecialHeaderSize); |
| 303 | #endif |
| 304 | |
| 305 | return True; |
| 306 | } |
| 307 | |
| 308 | char const* RawAMRRTPSource::MIMEtype() const { |
| 309 | return fIsWideband ? "audio/AMR-WB" : "audio/AMR" ; |
| 310 | } |
| 311 | |
| 312 | Boolean RawAMRRTPSource::hasBeenSynchronizedUsingRTCP() { |
| 313 | return fIsSynchronized; |
| 314 | } |
| 315 | |
| 316 | |
| 317 | ///// AMRBufferedPacket and AMRBufferedPacketFactory implementation |
| 318 | |
| 319 | AMRBufferedPacket::AMRBufferedPacket(RawAMRRTPSource& ourSource) |
| 320 | : fOurSource(ourSource) { |
| 321 | } |
| 322 | |
| 323 | AMRBufferedPacket::~AMRBufferedPacket() { |
| 324 | } |
| 325 | |
| 326 | // The mapping from the "FT" field to frame size. |
| 327 | // Values of 65535 are invalid. |
| 328 | #define FT_INVALID 65535 |
| 329 | static unsigned short const frameBytesFromFT[16] = { |
| 330 | 12, 13, 15, 17, |
| 331 | 19, 20, 26, 31, |
| 332 | 5, FT_INVALID, FT_INVALID, FT_INVALID, |
| 333 | FT_INVALID, FT_INVALID, FT_INVALID, 0 |
| 334 | }; |
| 335 | static unsigned short const frameBytesFromFTWideband[16] = { |
| 336 | 17, 23, 32, 36, |
| 337 | 40, 46, 50, 58, |
| 338 | 60, 5, FT_INVALID, FT_INVALID, |
| 339 | FT_INVALID, FT_INVALID, 0, 0 |
| 340 | }; |
| 341 | |
| 342 | unsigned AMRBufferedPacket:: |
| 343 | nextEnclosedFrameSize(unsigned char*& framePtr, unsigned dataSize) { |
| 344 | if (dataSize == 0) return 0; // sanity check |
| 345 | |
| 346 | // The size of the AMR frame is determined by the corresponding 'FT' value |
| 347 | // in the packet's Table of Contents. |
| 348 | unsigned const tocIndex = fOurSource.frameIndex(); |
| 349 | if (tocIndex >= fOurSource.TOCSize()) return 0; // sanity check |
| 350 | |
| 351 | unsigned char const tocByte = fOurSource.TOC()[tocIndex]; |
| 352 | unsigned char const FT = (tocByte&0x78) >> 3; |
| 353 | // ASSERT: FT < 16 |
| 354 | unsigned short frameSize |
| 355 | = fOurSource.isWideband() ? frameBytesFromFTWideband[FT] : frameBytesFromFT[FT]; |
| 356 | if (frameSize == FT_INVALID) { |
| 357 | // Strange TOC entry! |
| 358 | fOurSource.envir() << "AMRBufferedPacket::nextEnclosedFrameSize(): invalid FT: " << FT << "\n" ; |
| 359 | frameSize = 0; // This probably messes up the rest of this packet, but... |
| 360 | } |
| 361 | #ifdef DEBUG |
| 362 | fprintf(stderr, "AMRBufferedPacket::nextEnclosedFrameSize(): frame #: %d, FT: %d, isWideband: %d => frameSize: %d (dataSize: %d)\n" , tocIndex, FT, fOurSource.isWideband(), frameSize, dataSize); |
| 363 | #endif |
| 364 | ++fOurSource.frameIndex(); |
| 365 | |
| 366 | if (dataSize < frameSize) return 0; |
| 367 | return frameSize; |
| 368 | } |
| 369 | |
| 370 | BufferedPacket* AMRBufferedPacketFactory |
| 371 | ::createNewPacket(MultiFramedRTPSource* ourSource) { |
| 372 | return new AMRBufferedPacket((RawAMRRTPSource&)(*ourSource)); |
| 373 | } |
| 374 | |
| 375 | ///////// AMRDeinterleavingBuffer ///////// |
| 376 | // (used to implement AMRDeinterleaver) |
| 377 | |
| 378 | #define AMR_MAX_FRAME_SIZE 60 |
| 379 | |
| 380 | class AMRDeinterleavingBuffer { |
| 381 | public: |
| 382 | AMRDeinterleavingBuffer(unsigned numChannels, unsigned maxInterleaveGroupSize); |
| 383 | virtual ~AMRDeinterleavingBuffer(); |
| 384 | |
| 385 | void deliverIncomingFrame(unsigned frameSize, RawAMRRTPSource* source, |
| 386 | struct timeval presentationTime); |
| 387 | Boolean retrieveFrame(unsigned char* to, unsigned maxSize, |
| 388 | unsigned& resultFrameSize, unsigned& resultNumTruncatedBytes, |
| 389 | u_int8_t& , |
| 390 | struct timeval& resultPresentationTime, |
| 391 | Boolean& resultIsSynchronized); |
| 392 | |
| 393 | unsigned char* inputBuffer() { return fInputBuffer; } |
| 394 | unsigned inputBufferSize() const { return AMR_MAX_FRAME_SIZE; } |
| 395 | |
| 396 | private: |
| 397 | unsigned char* createNewBuffer(); |
| 398 | |
| 399 | class FrameDescriptor { |
| 400 | public: |
| 401 | FrameDescriptor(); |
| 402 | virtual ~FrameDescriptor(); |
| 403 | |
| 404 | unsigned frameSize; |
| 405 | unsigned char* frameData; |
| 406 | u_int8_t ; |
| 407 | struct timeval presentationTime; |
| 408 | Boolean fIsSynchronized; |
| 409 | }; |
| 410 | |
| 411 | unsigned fNumChannels, fMaxInterleaveGroupSize; |
| 412 | FrameDescriptor* fFrames[2]; |
| 413 | unsigned char fIncomingBankId; // toggles between 0 and 1 |
| 414 | unsigned char fIncomingBinMax; // in the incoming bank |
| 415 | unsigned char fOutgoingBinMax; // in the outgoing bank |
| 416 | unsigned char fNextOutgoingBin; |
| 417 | Boolean fHaveSeenPackets; |
| 418 | u_int16_t fLastPacketSeqNumForGroup; |
| 419 | unsigned char* fInputBuffer; |
| 420 | struct timeval fLastRetrievedPresentationTime; |
| 421 | unsigned fNumSuccessiveSyncedFrames; |
| 422 | unsigned char fILL; |
| 423 | }; |
| 424 | |
| 425 | |
| 426 | ////////// AMRDeinterleaver implementation ///////// |
| 427 | |
| 428 | AMRDeinterleaver* AMRDeinterleaver |
| 429 | ::createNew(UsageEnvironment& env, |
| 430 | Boolean isWideband, unsigned numChannels, unsigned maxInterleaveGroupSize, |
| 431 | RawAMRRTPSource* inputSource) { |
| 432 | return new AMRDeinterleaver(env, isWideband, numChannels, maxInterleaveGroupSize, inputSource); |
| 433 | } |
| 434 | |
| 435 | AMRDeinterleaver::AMRDeinterleaver(UsageEnvironment& env, |
| 436 | Boolean isWideband, unsigned numChannels, |
| 437 | unsigned maxInterleaveGroupSize, |
| 438 | RawAMRRTPSource* inputSource) |
| 439 | : AMRAudioSource(env, isWideband, numChannels), |
| 440 | fInputSource(inputSource), fNeedAFrame(False) { |
| 441 | fDeinterleavingBuffer |
| 442 | = new AMRDeinterleavingBuffer(numChannels, maxInterleaveGroupSize); |
| 443 | } |
| 444 | |
| 445 | AMRDeinterleaver::~AMRDeinterleaver() { |
| 446 | delete fDeinterleavingBuffer; |
| 447 | Medium::close(fInputSource); |
| 448 | } |
| 449 | |
| 450 | static unsigned const uSecsPerFrame = 20000; // 20 ms |
| 451 | |
| 452 | void AMRDeinterleaver::doGetNextFrame() { |
| 453 | // First, try getting a frame from the deinterleaving buffer: |
| 454 | if (fDeinterleavingBuffer->retrieveFrame(fTo, fMaxSize, |
| 455 | fFrameSize, fNumTruncatedBytes, |
| 456 | fLastFrameHeader, fPresentationTime, |
| 457 | fInputSource->isSynchronized())) { |
| 458 | |
| 459 | // Success! |
| 460 | fNeedAFrame = False; |
| 461 | |
| 462 | fDurationInMicroseconds = uSecsPerFrame; |
| 463 | |
| 464 | // Call our own 'after getting' function. Because we're not a 'leaf' |
| 465 | // source, we can call this directly, without risking |
| 466 | // infinite recursion |
| 467 | afterGetting(this); |
| 468 | return; |
| 469 | } |
| 470 | |
| 471 | // No luck, so ask our source for help: |
| 472 | fNeedAFrame = True; |
| 473 | if (!fInputSource->isCurrentlyAwaitingData()) { |
| 474 | fInputSource->getNextFrame(fDeinterleavingBuffer->inputBuffer(), |
| 475 | fDeinterleavingBuffer->inputBufferSize(), |
| 476 | afterGettingFrame, this, |
| 477 | FramedSource::handleClosure, this); |
| 478 | } |
| 479 | } |
| 480 | |
| 481 | void AMRDeinterleaver::doStopGettingFrames() { |
| 482 | fNeedAFrame = False; |
| 483 | fInputSource->stopGettingFrames(); |
| 484 | } |
| 485 | |
| 486 | void AMRDeinterleaver |
| 487 | ::afterGettingFrame(void* clientData, unsigned frameSize, |
| 488 | unsigned /*numTruncatedBytes*/, |
| 489 | struct timeval presentationTime, |
| 490 | unsigned /*durationInMicroseconds*/) { |
| 491 | AMRDeinterleaver* deinterleaver = (AMRDeinterleaver*)clientData; |
| 492 | deinterleaver->afterGettingFrame1(frameSize, presentationTime); |
| 493 | } |
| 494 | |
| 495 | void AMRDeinterleaver |
| 496 | ::afterGettingFrame1(unsigned frameSize, struct timeval presentationTime) { |
| 497 | RawAMRRTPSource* source = (RawAMRRTPSource*)fInputSource; |
| 498 | |
| 499 | // First, put the frame into our deinterleaving buffer: |
| 500 | fDeinterleavingBuffer->deliverIncomingFrame(frameSize, source, presentationTime); |
| 501 | |
| 502 | // Then, try delivering a frame to the client (if he wants one): |
| 503 | if (fNeedAFrame) doGetNextFrame(); |
| 504 | } |
| 505 | |
| 506 | |
| 507 | ////////// AMRDeinterleavingBuffer implementation ///////// |
| 508 | |
| 509 | AMRDeinterleavingBuffer |
| 510 | ::AMRDeinterleavingBuffer(unsigned numChannels, unsigned maxInterleaveGroupSize) |
| 511 | : fNumChannels(numChannels), fMaxInterleaveGroupSize(maxInterleaveGroupSize), |
| 512 | fIncomingBankId(0), fIncomingBinMax(0), |
| 513 | fOutgoingBinMax(0), fNextOutgoingBin(0), |
| 514 | fHaveSeenPackets(False), fNumSuccessiveSyncedFrames(0), fILL(0) { |
| 515 | // Use two banks of descriptors - one for incoming, one for outgoing |
| 516 | fFrames[0] = new FrameDescriptor[fMaxInterleaveGroupSize]; |
| 517 | fFrames[1] = new FrameDescriptor[fMaxInterleaveGroupSize]; |
| 518 | fInputBuffer = createNewBuffer(); |
| 519 | } |
| 520 | |
| 521 | AMRDeinterleavingBuffer::~AMRDeinterleavingBuffer() { |
| 522 | delete[] fInputBuffer; |
| 523 | delete[] fFrames[0]; delete[] fFrames[1]; |
| 524 | } |
| 525 | |
| 526 | void AMRDeinterleavingBuffer |
| 527 | ::deliverIncomingFrame(unsigned frameSize, RawAMRRTPSource* source, |
| 528 | struct timeval presentationTime) { |
| 529 | fILL = source->ILL(); |
| 530 | unsigned char const ILP = source->ILP(); |
| 531 | unsigned frameIndex = source->frameIndex(); |
| 532 | unsigned short packetSeqNum = source->curPacketRTPSeqNum(); |
| 533 | |
| 534 | // First perform a sanity check on the parameters: |
| 535 | // (This is overkill, as the source should have already done this.) |
| 536 | if (ILP > fILL || frameIndex == 0) { |
| 537 | #ifdef DEBUG |
| 538 | fprintf(stderr, "AMRDeinterleavingBuffer::deliverIncomingFrame() param sanity check failed (%d,%d,%d,%d)\n" , frameSize, fILL, ILP, frameIndex); |
| 539 | #endif |
| 540 | source->envir().internalError(); |
| 541 | } |
| 542 | |
| 543 | --frameIndex; // because it was incremented by the source when this frame was read |
| 544 | u_int8_t ; |
| 545 | if (frameIndex >= source->TOCSize()) { // sanity check |
| 546 | frameHeader = FT_NO_DATA<<3; |
| 547 | } else { |
| 548 | frameHeader = source->TOC()[frameIndex]; |
| 549 | } |
| 550 | |
| 551 | unsigned frameBlockIndex = frameIndex/fNumChannels; |
| 552 | unsigned frameWithinFrameBlock = frameIndex%fNumChannels; |
| 553 | |
| 554 | // The input "presentationTime" was that of the first frame-block in this |
| 555 | // packet. Update it for the current frame: |
| 556 | unsigned uSecIncrement = frameBlockIndex*(fILL+1)*uSecsPerFrame; |
| 557 | presentationTime.tv_usec += uSecIncrement; |
| 558 | presentationTime.tv_sec += presentationTime.tv_usec/1000000; |
| 559 | presentationTime.tv_usec = presentationTime.tv_usec%1000000; |
| 560 | |
| 561 | // Next, check whether this packet is part of a new interleave group |
| 562 | if (!fHaveSeenPackets |
| 563 | || seqNumLT(fLastPacketSeqNumForGroup, packetSeqNum + frameBlockIndex)) { |
| 564 | // We've moved to a new interleave group |
| 565 | #ifdef DEBUG |
| 566 | fprintf(stderr, "AMRDeinterleavingBuffer::deliverIncomingFrame(): new interleave group\n" ); |
| 567 | #endif |
| 568 | fHaveSeenPackets = True; |
| 569 | fLastPacketSeqNumForGroup = packetSeqNum + fILL - ILP; |
| 570 | |
| 571 | // Switch the incoming and outgoing banks: |
| 572 | fIncomingBankId ^= 1; |
| 573 | unsigned char tmp = fIncomingBinMax; |
| 574 | fIncomingBinMax = fOutgoingBinMax; |
| 575 | fOutgoingBinMax = tmp; |
| 576 | fNextOutgoingBin = 0; |
| 577 | } |
| 578 | |
| 579 | // Now move the incoming frame into the appropriate bin: |
| 580 | unsigned const binNumber |
| 581 | = ((ILP + frameBlockIndex*(fILL+1))*fNumChannels + frameWithinFrameBlock) |
| 582 | % fMaxInterleaveGroupSize; // the % is for sanity |
| 583 | #ifdef DEBUG |
| 584 | fprintf(stderr, "AMRDeinterleavingBuffer::deliverIncomingFrame(): frameIndex %d (%d,%d) put in bank %d, bin %d (%d): size %d, header 0x%02x, presentationTime %lu.%06ld\n" , frameIndex, frameBlockIndex, frameWithinFrameBlock, fIncomingBankId, binNumber, fMaxInterleaveGroupSize, frameSize, frameHeader, presentationTime.tv_sec, presentationTime.tv_usec); |
| 585 | #endif |
| 586 | FrameDescriptor& inBin = fFrames[fIncomingBankId][binNumber]; |
| 587 | unsigned char* curBuffer = inBin.frameData; |
| 588 | inBin.frameData = fInputBuffer; |
| 589 | inBin.frameSize = frameSize; |
| 590 | inBin.frameHeader = frameHeader; |
| 591 | inBin.presentationTime = presentationTime; |
| 592 | inBin.fIsSynchronized = ((RTPSource*)source)->RTPSource::hasBeenSynchronizedUsingRTCP(); |
| 593 | |
| 594 | if (curBuffer == NULL) curBuffer = createNewBuffer(); |
| 595 | fInputBuffer = curBuffer; |
| 596 | |
| 597 | if (binNumber >= fIncomingBinMax) { |
| 598 | fIncomingBinMax = binNumber + 1; |
| 599 | } |
| 600 | } |
| 601 | |
| 602 | Boolean AMRDeinterleavingBuffer |
| 603 | ::retrieveFrame(unsigned char* to, unsigned maxSize, |
| 604 | unsigned& resultFrameSize, unsigned& resultNumTruncatedBytes, |
| 605 | u_int8_t& , |
| 606 | struct timeval& resultPresentationTime, |
| 607 | Boolean& resultIsSynchronized) { |
| 608 | |
| 609 | if (fNextOutgoingBin >= fOutgoingBinMax) return False; // none left |
| 610 | |
| 611 | FrameDescriptor& outBin = fFrames[fIncomingBankId^1][fNextOutgoingBin]; |
| 612 | unsigned char* fromPtr = outBin.frameData; |
| 613 | unsigned char fromSize = outBin.frameSize; |
| 614 | outBin.frameSize = 0; // for the next time this bin is used |
| 615 | resultIsSynchronized = False; // by default; can be changed by: |
| 616 | if (outBin.fIsSynchronized) { |
| 617 | // Don't consider the outgoing frame to be synchronized until we've received at least a complete interleave cycle of |
| 618 | // synchronized frames. This ensures that the receiver will be getting all synchronized frames from now on. |
| 619 | if (++fNumSuccessiveSyncedFrames > fILL) { |
| 620 | resultIsSynchronized = True; |
| 621 | fNumSuccessiveSyncedFrames = fILL+1; // prevents overflow |
| 622 | } |
| 623 | } else { |
| 624 | fNumSuccessiveSyncedFrames = 0; |
| 625 | } |
| 626 | |
| 627 | // Check whether this frame is missing; if so, return a FT_NO_DATA frame: |
| 628 | if (fromSize == 0) { |
| 629 | resultFrameHeader = FT_NO_DATA<<3; |
| 630 | |
| 631 | // Compute this erasure frame's presentation time via extrapolation: |
| 632 | resultPresentationTime = fLastRetrievedPresentationTime; |
| 633 | resultPresentationTime.tv_usec += uSecsPerFrame; |
| 634 | if (resultPresentationTime.tv_usec >= 1000000) { |
| 635 | ++resultPresentationTime.tv_sec; |
| 636 | resultPresentationTime.tv_usec -= 1000000; |
| 637 | } |
| 638 | } else { |
| 639 | // Normal case - a frame exists: |
| 640 | resultFrameHeader = outBin.frameHeader; |
| 641 | resultPresentationTime = outBin.presentationTime; |
| 642 | } |
| 643 | |
| 644 | fLastRetrievedPresentationTime = resultPresentationTime; |
| 645 | |
| 646 | if (fromSize > maxSize) { |
| 647 | resultNumTruncatedBytes = fromSize - maxSize; |
| 648 | resultFrameSize = maxSize; |
| 649 | } else { |
| 650 | resultNumTruncatedBytes = 0; |
| 651 | resultFrameSize = fromSize; |
| 652 | } |
| 653 | memmove(to, fromPtr, resultFrameSize); |
| 654 | #ifdef DEBUG |
| 655 | fprintf(stderr, "AMRDeinterleavingBuffer::retrieveFrame(): from bank %d, bin %d: size %d, header 0x%02x, presentationTime %lu.%06ld\n" , fIncomingBankId^1, fNextOutgoingBin, resultFrameSize, resultFrameHeader, resultPresentationTime.tv_sec, resultPresentationTime.tv_usec); |
| 656 | #endif |
| 657 | |
| 658 | ++fNextOutgoingBin; |
| 659 | return True; |
| 660 | } |
| 661 | |
| 662 | unsigned char* AMRDeinterleavingBuffer::createNewBuffer() { |
| 663 | return new unsigned char[inputBufferSize()]; |
| 664 | } |
| 665 | |
| 666 | AMRDeinterleavingBuffer::FrameDescriptor::FrameDescriptor() |
| 667 | : frameSize(0), frameData(NULL) { |
| 668 | } |
| 669 | |
| 670 | AMRDeinterleavingBuffer::FrameDescriptor::~FrameDescriptor() { |
| 671 | delete[] frameData; |
| 672 | } |
| 673 | |
| 674 | // Unpack bandwidth-aligned data to octet-aligned: |
| 675 | static unsigned short const frameBitsFromFT[16] = { |
| 676 | 95, 103, 118, 134, |
| 677 | 148, 159, 204, 244, |
| 678 | 39, 0, 0, 0, |
| 679 | 0, 0, 0, 0 |
| 680 | }; |
| 681 | static unsigned short const frameBitsFromFTWideband[16] = { |
| 682 | 132, 177, 253, 285, |
| 683 | 317, 365, 397, 461, |
| 684 | 477, 40, 0, 0, |
| 685 | 0, 0, 0, 0 |
| 686 | }; |
| 687 | |
| 688 | static void unpackBandwidthEfficientData(BufferedPacket* packet, |
| 689 | Boolean isWideband) { |
| 690 | #ifdef DEBUG |
| 691 | fprintf(stderr, "Unpacking 'bandwidth-efficient' payload (%d bytes):\n" , packet->dataSize()); |
| 692 | for (unsigned j = 0; j < packet->dataSize(); ++j) { |
| 693 | fprintf(stderr, "%02x:" , (packet->data())[j]); |
| 694 | } |
| 695 | fprintf(stderr, "\n" ); |
| 696 | #endif |
| 697 | BitVector fromBV(packet->data(), 0, 8*packet->dataSize()); |
| 698 | |
| 699 | unsigned const toBufferSize = 2*packet->dataSize(); // conservatively large |
| 700 | unsigned char* toBuffer = new unsigned char[toBufferSize]; |
| 701 | unsigned toCount = 0; |
| 702 | |
| 703 | // Begin with the payload header: |
| 704 | unsigned CMR = fromBV.getBits(4); |
| 705 | toBuffer[toCount++] = CMR << 4; |
| 706 | |
| 707 | // Then, run through and unpack the TOC entries: |
| 708 | while (1) { |
| 709 | unsigned toc = fromBV.getBits(6); |
| 710 | toBuffer[toCount++] = toc << 2; |
| 711 | |
| 712 | if ((toc&0x20) == 0) break; // the F bit is 0 |
| 713 | } |
| 714 | |
| 715 | // Then, using the TOC data, unpack each frame payload: |
| 716 | unsigned const tocSize = toCount - 1; |
| 717 | for (unsigned i = 1; i <= tocSize; ++i) { |
| 718 | unsigned char tocByte = toBuffer[i]; |
| 719 | unsigned char const FT = (tocByte&0x78) >> 3; |
| 720 | unsigned short frameSizeBits |
| 721 | = isWideband ? frameBitsFromFTWideband[FT] : frameBitsFromFT[FT]; |
| 722 | unsigned short frameSizeBytes = (frameSizeBits+7)/8; |
| 723 | |
| 724 | if (frameSizeBits > fromBV.numBitsRemaining()) { |
| 725 | #ifdef DEBUG |
| 726 | fprintf(stderr, "\tWarning: Unpacking frame %d of %d: want %d bits, but only %d are available!\n" , i, tocSize, frameSizeBits, fromBV.numBitsRemaining()); |
| 727 | #endif |
| 728 | break; |
| 729 | } |
| 730 | |
| 731 | shiftBits(&toBuffer[toCount], 0, // to |
| 732 | packet->data(), fromBV.curBitIndex(), // from |
| 733 | frameSizeBits // num bits |
| 734 | ); |
| 735 | fromBV.skipBits(frameSizeBits); |
| 736 | toCount += frameSizeBytes; |
| 737 | } |
| 738 | |
| 739 | #ifdef DEBUG |
| 740 | if (fromBV.numBitsRemaining() > 7) { |
| 741 | fprintf(stderr, "\tWarning: %d bits remain unused!\n" , fromBV.numBitsRemaining()); |
| 742 | } |
| 743 | #endif |
| 744 | |
| 745 | // Finally, replace the current packet data with the unpacked data: |
| 746 | packet->removePadding(packet->dataSize()); // throws away current packet data |
| 747 | packet->appendData(toBuffer, toCount); |
| 748 | delete[] toBuffer; |
| 749 | } |
| 750 | |