1 /* 2 * Copyright 2014 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 //#define LOG_NDEBUG 0 18 #define LOG_TAG "NuPlayerCCDecoder" 19 #include <utils/Log.h> 20 #include <inttypes.h> 21 22 #include "avc_utils.h" 23 #include "NuPlayerCCDecoder.h" 24 25 #include <media/stagefright/foundation/ABitReader.h> 26 #include <media/stagefright/foundation/ABuffer.h> 27 #include <media/stagefright/foundation/ADebug.h> 28 #include <media/stagefright/foundation/AMessage.h> 29 #include <media/stagefright/MediaDefs.h> 30 31 namespace android { 32 33 // In CEA-708B, the maximum bandwidth of CC is set to 9600bps. 34 static const size_t kMaxBandwithSizeBytes = 9600 / 8; 35 36 struct CCData { 37 CCData(uint8_t type, uint8_t data1, uint8_t data2) 38 : mType(type), mData1(data1), mData2(data2) { 39 } 40 bool getChannel(size_t *channel) const { 41 if (mData1 >= 0x10 && mData1 <= 0x1f) { 42 *channel = (mData1 >= 0x18 ? 1 : 0) + (mType ? 2 : 0); 43 return true; 44 } 45 return false; 46 } 47 48 uint8_t mType; 49 uint8_t mData1; 50 uint8_t mData2; 51 }; 52 53 static bool isNullPad(CCData *cc) { 54 return cc->mData1 < 0x10 && cc->mData2 < 0x10; 55 } 56 57 static void dumpBytePair(const sp<ABuffer> &ccBuf) __attribute__ ((unused)); 58 static void dumpBytePair(const sp<ABuffer> &ccBuf) { 59 size_t offset = 0; 60 AString out; 61 62 while (offset < ccBuf->size()) { 63 char tmp[128]; 64 65 CCData *cc = (CCData *) (ccBuf->data() + offset); 66 67 if (isNullPad(cc)) { 68 // 1 null pad or XDS metadata, ignore 69 offset += sizeof(CCData); 70 continue; 71 } 72 73 if (cc->mData1 >= 0x20 && cc->mData1 <= 0x7f) { 74 // 2 basic chars 75 sprintf(tmp, "[%d]Basic: %c %c", cc->mType, cc->mData1, cc->mData2); 76 } else if ((cc->mData1 == 0x11 || cc->mData1 == 0x19) 77 && cc->mData2 >= 0x30 && cc->mData2 <= 0x3f) { 78 // 1 special char 79 sprintf(tmp, "[%d]Special: %02x %02x", cc->mType, cc->mData1, cc->mData2); 80 } else if ((cc->mData1 == 0x12 || cc->mData1 == 0x1A) 81 && cc->mData2 >= 0x20 && cc->mData2 <= 0x3f){ 82 // 1 Spanish/French char 83 sprintf(tmp, "[%d]Spanish: %02x %02x", cc->mType, cc->mData1, cc->mData2); 84 } else if ((cc->mData1 == 0x13 || cc->mData1 == 0x1B) 85 && cc->mData2 >= 0x20 && cc->mData2 <= 0x3f){ 86 // 1 Portuguese/German/Danish char 87 sprintf(tmp, "[%d]German: %02x %02x", cc->mType, cc->mData1, cc->mData2); 88 } else if ((cc->mData1 == 0x11 || cc->mData1 == 0x19) 89 && cc->mData2 >= 0x20 && cc->mData2 <= 0x2f){ 90 // Mid-Row Codes (Table 69) 91 sprintf(tmp, "[%d]Mid-row: %02x %02x", cc->mType, cc->mData1, cc->mData2); 92 } else if (((cc->mData1 == 0x14 || cc->mData1 == 0x1c) 93 && cc->mData2 >= 0x20 && cc->mData2 <= 0x2f) 94 || 95 ((cc->mData1 == 0x17 || cc->mData1 == 0x1f) 96 && cc->mData2 >= 0x21 && cc->mData2 <= 0x23)){ 97 // Misc Control Codes (Table 70) 98 sprintf(tmp, "[%d]Ctrl: %02x %02x", cc->mType, cc->mData1, cc->mData2); 99 } else if ((cc->mData1 & 0x70) == 0x10 100 && (cc->mData2 & 0x40) == 0x40 101 && ((cc->mData1 & 0x07) || !(cc->mData2 & 0x20)) ) { 102 // Preamble Address Codes (Table 71) 103 sprintf(tmp, "[%d]PAC: %02x %02x", cc->mType, cc->mData1, cc->mData2); 104 } else { 105 sprintf(tmp, "[%d]Invalid: %02x %02x", cc->mType, cc->mData1, cc->mData2); 106 } 107 108 if (out.size() > 0) { 109 out.append(", "); 110 } 111 112 out.append(tmp); 113 114 offset += sizeof(CCData); 115 } 116 117 ALOGI("%s", out.c_str()); 118 } 119 120 NuPlayer::CCDecoder::CCDecoder(const sp<AMessage> ¬ify) 121 : mNotify(notify), 122 mSelectedTrack(-1), 123 mDTVCCPacket(new ABuffer(kMaxBandwithSizeBytes)) { 124 mDTVCCPacket->setRange(0, 0); 125 126 // In CEA-608, streams from packets which have the value 0 of cc_type contain CC1 and CC2, and 127 // streams from packets which have the value 1 of cc_type contain CC3 and CC4. 128 // The following array indicates the current transmitting channels for each value of cc_type. 129 mLine21Channels[0] = 0; // CC1 130 mLine21Channels[1] = 2; // CC3 131 } 132 133 size_t NuPlayer::CCDecoder::getTrackCount() const { 134 return mTracks.size(); 135 } 136 137 sp<AMessage> NuPlayer::CCDecoder::getTrackInfo(size_t index) const { 138 if (!isTrackValid(index)) { 139 return NULL; 140 } 141 142 sp<AMessage> format = new AMessage(); 143 144 CCTrack track = mTracks[index]; 145 146 format->setInt32("type", MEDIA_TRACK_TYPE_SUBTITLE); 147 format->setString("language", "und"); 148 149 switch (track.mTrackType) { 150 case kTrackTypeCEA608: 151 format->setString("mime", MEDIA_MIMETYPE_TEXT_CEA_608); 152 break; 153 case kTrackTypeCEA708: 154 format->setString("mime", MEDIA_MIMETYPE_TEXT_CEA_708); 155 break; 156 default: 157 ALOGE("Unknown track type: %d", track.mTrackType); 158 return NULL; 159 } 160 161 // For CEA-608 CC1, field 0 channel 0 162 bool isDefaultAuto = track.mTrackType == kTrackTypeCEA608 163 && track.mTrackChannel == 0; 164 // For CEA-708, Primary Caption Service. 165 bool isDefaultOnly = track.mTrackType == kTrackTypeCEA708 166 && track.mTrackChannel == 1; 167 format->setInt32("auto", isDefaultAuto); 168 format->setInt32("default", isDefaultAuto || isDefaultOnly); 169 format->setInt32("forced", 0); 170 171 return format; 172 } 173 174 status_t NuPlayer::CCDecoder::selectTrack(size_t index, bool select) { 175 if (!isTrackValid(index)) { 176 return BAD_VALUE; 177 } 178 179 if (select) { 180 if (mSelectedTrack == (ssize_t)index) { 181 ALOGE("track %zu already selected", index); 182 return BAD_VALUE; 183 } 184 ALOGV("selected track %zu", index); 185 mSelectedTrack = index; 186 } else { 187 if (mSelectedTrack != (ssize_t)index) { 188 ALOGE("track %zu is not selected", index); 189 return BAD_VALUE; 190 } 191 ALOGV("unselected track %zu", index); 192 mSelectedTrack = -1; 193 } 194 195 // Clear the previous track payloads 196 mCCMap.clear(); 197 198 return OK; 199 } 200 201 bool NuPlayer::CCDecoder::isSelected() const { 202 return mSelectedTrack >= 0 && mSelectedTrack < (int32_t)getTrackCount(); 203 } 204 205 bool NuPlayer::CCDecoder::isTrackValid(size_t index) const { 206 return index < getTrackCount(); 207 } 208 209 // returns true if a new CC track is found 210 bool NuPlayer::CCDecoder::extractFromSEI(const sp<ABuffer> &accessUnit) { 211 sp<ABuffer> sei; 212 if (!accessUnit->meta()->findBuffer("sei", &sei) || sei == NULL) { 213 return false; 214 } 215 216 int64_t timeUs; 217 CHECK(accessUnit->meta()->findInt64("timeUs", &timeUs)); 218 219 bool trackAdded = false; 220 221 const NALPosition *nal = (NALPosition *)sei->data(); 222 223 for (size_t i = 0; i < sei->size() / sizeof(NALPosition); ++i, ++nal) { 224 trackAdded |= parseSEINalUnit( 225 timeUs, accessUnit->data() + nal->nalOffset, nal->nalSize); 226 } 227 228 return trackAdded; 229 } 230 231 // returns true if a new CC track is found 232 bool NuPlayer::CCDecoder::parseSEINalUnit(int64_t timeUs, const uint8_t *data, size_t size) { 233 unsigned nalType = data[0] & 0x1f; 234 235 // the buffer should only have SEI in it 236 if (nalType != 6) { 237 return false; 238 } 239 240 bool trackAdded = false; 241 NALBitReader br(data + 1, size - 1); 242 243 // sei_message() 244 while (br.atLeastNumBitsLeft(16)) { // at least 16-bit for sei_message() 245 uint32_t payload_type = 0; 246 size_t payload_size = 0; 247 uint8_t last_byte; 248 249 do { 250 last_byte = br.getBits(8); 251 payload_type += last_byte; 252 } while (last_byte == 0xFF); 253 254 do { 255 last_byte = br.getBits(8); 256 payload_size += last_byte; 257 } while (last_byte == 0xFF); 258 259 // sei_payload() 260 if (payload_type == 4) { 261 bool isCC = false; 262 if (payload_size > 1 + 2 + 4 + 1) { 263 // user_data_registered_itu_t_t35() 264 265 // ATSC A/72: 6.4.2 266 uint8_t itu_t_t35_country_code = br.getBits(8); 267 uint16_t itu_t_t35_provider_code = br.getBits(16); 268 uint32_t user_identifier = br.getBits(32); 269 uint8_t user_data_type_code = br.getBits(8); 270 271 payload_size -= 1 + 2 + 4 + 1; 272 273 isCC = itu_t_t35_country_code == 0xB5 274 && itu_t_t35_provider_code == 0x0031 275 && user_identifier == 'GA94' 276 && user_data_type_code == 0x3; 277 } 278 279 if (isCC && payload_size > 2) { 280 trackAdded |= parseMPEGCCData(timeUs, br.data(), br.numBitsLeft() / 8); 281 } else { 282 ALOGV("Malformed SEI payload type 4"); 283 } 284 } else { 285 ALOGV("Unsupported SEI payload type %d", payload_type); 286 } 287 288 // skipping remaining bits of this payload 289 br.skipBits(payload_size * 8); 290 } 291 292 return trackAdded; 293 } 294 295 // returns true if a new CC track is found 296 bool NuPlayer::CCDecoder::extractFromMPEGUserData(const sp<ABuffer> &accessUnit) { 297 sp<ABuffer> mpegUserData; 298 if (!accessUnit->meta()->findBuffer("mpegUserData", &mpegUserData) 299 || mpegUserData == NULL) { 300 return false; 301 } 302 303 int64_t timeUs; 304 CHECK(accessUnit->meta()->findInt64("timeUs", &timeUs)); 305 306 bool trackAdded = false; 307 308 const size_t *userData = (size_t *)mpegUserData->data(); 309 310 for (size_t i = 0; i < mpegUserData->size() / sizeof(size_t); ++i) { 311 trackAdded |= parseMPEGUserDataUnit( 312 timeUs, accessUnit->data() + userData[i], accessUnit->size() - userData[i]); 313 } 314 315 return trackAdded; 316 } 317 318 // returns true if a new CC track is found 319 bool NuPlayer::CCDecoder::parseMPEGUserDataUnit(int64_t timeUs, const uint8_t *data, size_t size) { 320 ABitReader br(data + 4, 5); 321 322 uint32_t user_identifier = br.getBits(32); 323 uint8_t user_data_type = br.getBits(8); 324 325 if (user_identifier == 'GA94' && user_data_type == 0x3) { 326 return parseMPEGCCData(timeUs, data + 9, size - 9); 327 } 328 329 return false; 330 } 331 332 // returns true if a new CC track is found 333 bool NuPlayer::CCDecoder::parseMPEGCCData(int64_t timeUs, const uint8_t *data, size_t size) { 334 bool trackAdded = false; 335 336 // MPEG_cc_data() 337 // ATSC A/53 Part 4: 6.2.3.1 338 ABitReader br(data, size); 339 340 if (br.numBitsLeft() <= 16) { 341 return false; 342 } 343 344 br.skipBits(1); 345 bool process_cc_data_flag = br.getBits(1); 346 br.skipBits(1); 347 size_t cc_count = br.getBits(5); 348 br.skipBits(8); 349 350 if (!process_cc_data_flag || 3 * 8 * cc_count >= br.numBitsLeft()) { 351 return false; 352 } 353 354 sp<ABuffer> line21CCBuf = NULL; 355 356 for (size_t i = 0; i < cc_count; ++i) { 357 br.skipBits(5); 358 bool cc_valid = br.getBits(1); 359 uint8_t cc_type = br.getBits(2); 360 361 if (cc_valid) { 362 if (cc_type == 3) { 363 if (mDTVCCPacket->size() > 0) { 364 trackAdded |= parseDTVCCPacket( 365 timeUs, mDTVCCPacket->data(), mDTVCCPacket->size()); 366 mDTVCCPacket->setRange(0, 0); 367 } 368 memcpy(mDTVCCPacket->data() + mDTVCCPacket->size(), br.data(), 2); 369 mDTVCCPacket->setRange(0, mDTVCCPacket->size() + 2); 370 br.skipBits(16); 371 } else if (mDTVCCPacket->size() > 0 && cc_type == 2) { 372 memcpy(mDTVCCPacket->data() + mDTVCCPacket->size(), br.data(), 2); 373 mDTVCCPacket->setRange(0, mDTVCCPacket->size() + 2); 374 br.skipBits(16); 375 } else if (cc_type == 0 || cc_type == 1) { 376 uint8_t cc_data_1 = br.getBits(8) & 0x7f; 377 uint8_t cc_data_2 = br.getBits(8) & 0x7f; 378 379 CCData cc(cc_type, cc_data_1, cc_data_2); 380 381 if (isNullPad(&cc)) { 382 continue; 383 } 384 385 size_t channel; 386 if (cc.getChannel(&channel)) { 387 mLine21Channels[cc_type] = channel; 388 389 // create a new track if it does not exist. 390 getTrackIndex(kTrackTypeCEA608, channel, &trackAdded); 391 } 392 393 if (isSelected() && mTracks[mSelectedTrack].mTrackType == kTrackTypeCEA608 394 && mTracks[mSelectedTrack].mTrackChannel == mLine21Channels[cc_type]) { 395 if (line21CCBuf == NULL) { 396 line21CCBuf = new ABuffer((cc_count - i) * sizeof(CCData)); 397 line21CCBuf->setRange(0, 0); 398 } 399 memcpy(line21CCBuf->data() + line21CCBuf->size(), &cc, sizeof(cc)); 400 line21CCBuf->setRange(0, line21CCBuf->size() + sizeof(CCData)); 401 } 402 } else { 403 br.skipBits(16); 404 } 405 } else { 406 if ((cc_type == 3 || cc_type == 2) && mDTVCCPacket->size() > 0) { 407 trackAdded |= parseDTVCCPacket(timeUs, mDTVCCPacket->data(), mDTVCCPacket->size()); 408 mDTVCCPacket->setRange(0, 0); 409 } 410 br.skipBits(16); 411 } 412 } 413 414 if (isSelected() && mTracks[mSelectedTrack].mTrackType == kTrackTypeCEA608 415 && line21CCBuf != NULL && line21CCBuf->size() > 0) { 416 mCCMap.add(timeUs, line21CCBuf); 417 } 418 419 return trackAdded; 420 } 421 422 // returns true if a new CC track is found 423 bool NuPlayer::CCDecoder::parseDTVCCPacket(int64_t timeUs, const uint8_t *data, size_t size) { 424 // CEA-708B 5 DTVCC Packet Layer. 425 ABitReader br(data, size); 426 br.skipBits(2); 427 428 size_t packet_size = br.getBits(6); 429 if (packet_size == 0) packet_size = 64; 430 packet_size *= 2; 431 432 if (size != packet_size) { 433 return false; 434 } 435 436 bool trackAdded = false; 437 438 while (br.numBitsLeft() >= 16) { 439 // CEA-708B Figure 5 and 6. 440 uint8_t service_number = br.getBits(3); 441 size_t block_size = br.getBits(5); 442 443 if (service_number == 64) { 444 br.skipBits(2); 445 service_number = br.getBits(6); 446 447 if (service_number < 64) { 448 return trackAdded; 449 } 450 } 451 452 if (br.numBitsLeft() < block_size * 8) { 453 return trackAdded; 454 } 455 456 if (block_size > 0) { 457 size_t trackIndex = getTrackIndex(kTrackTypeCEA708, service_number, &trackAdded); 458 if (mSelectedTrack == (ssize_t)trackIndex) { 459 sp<ABuffer> ccPacket = new ABuffer(block_size); 460 memcpy(ccPacket->data(), br.data(), block_size); 461 mCCMap.add(timeUs, ccPacket); 462 } 463 } 464 br.skipBits(block_size * 8); 465 } 466 467 return trackAdded; 468 } 469 470 // return the track index for a given type and channel. 471 // if the track does not exist, creates a new one. 472 size_t NuPlayer::CCDecoder::getTrackIndex( 473 int32_t trackType, size_t channel, bool *trackAdded) { 474 CCTrack track(trackType, channel); 475 ssize_t index = mTrackIndices.indexOfKey(track); 476 477 if (index < 0) { 478 // A new track is added. 479 index = mTracks.size(); 480 mTrackIndices.add(track, index); 481 mTracks.add(track); 482 *trackAdded = true; 483 return index; 484 } 485 486 return mTrackIndices.valueAt(index); 487 } 488 489 void NuPlayer::CCDecoder::decode(const sp<ABuffer> &accessUnit) { 490 if (extractFromMPEGUserData(accessUnit) || extractFromSEI(accessUnit)) { 491 sp<AMessage> msg = mNotify->dup(); 492 msg->setInt32("what", kWhatTrackAdded); 493 msg->post(); 494 } 495 // TODO: extract CC from other sources 496 } 497 498 void NuPlayer::CCDecoder::display(int64_t timeUs) { 499 if (!isSelected()) { 500 return; 501 } 502 503 ssize_t index = mCCMap.indexOfKey(timeUs); 504 if (index < 0) { 505 ALOGV("cc for timestamp %" PRId64 " not found", timeUs); 506 return; 507 } 508 509 sp<ABuffer> ccBuf; 510 511 if (index == 0) { 512 ccBuf = mCCMap.valueAt(index); 513 } else { 514 size_t size = 0; 515 516 for (ssize_t i = 0; i <= index; ++i) { 517 size += mCCMap.valueAt(i)->size(); 518 } 519 520 ccBuf = new ABuffer(size); 521 ccBuf->setRange(0, 0); 522 523 for (ssize_t i = 0; i <= index; ++i) { 524 sp<ABuffer> buf = mCCMap.valueAt(i); 525 memcpy(ccBuf->data() + ccBuf->size(), buf->data(), buf->size()); 526 ccBuf->setRange(0, ccBuf->size() + buf->size()); 527 } 528 } 529 530 if (ccBuf->size() > 0) { 531 #if 0 532 dumpBytePair(ccBuf); 533 #endif 534 535 ccBuf->meta()->setInt32("trackIndex", mSelectedTrack); 536 ccBuf->meta()->setInt64("timeUs", timeUs); 537 ccBuf->meta()->setInt64("durationUs", 0ll); 538 539 sp<AMessage> msg = mNotify->dup(); 540 msg->setInt32("what", kWhatClosedCaptionData); 541 msg->setBuffer("buffer", ccBuf); 542 msg->post(); 543 } 544 545 // remove all entries before timeUs 546 mCCMap.removeItemsAt(0, index + 1); 547 } 548 549 void NuPlayer::CCDecoder::flush() { 550 mCCMap.clear(); 551 mDTVCCPacket->setRange(0, 0); 552 } 553 554 int32_t NuPlayer::CCDecoder::CCTrack::compare(const NuPlayer::CCDecoder::CCTrack& rhs) const { 555 int32_t cmp = mTrackType - rhs.mTrackType; 556 if (cmp != 0) return cmp; 557 return mTrackChannel - rhs.mTrackChannel; 558 } 559 560 bool NuPlayer::CCDecoder::CCTrack::operator<(const NuPlayer::CCDecoder::CCTrack& rhs) const { 561 return compare(rhs) < 0; 562 } 563 564 bool NuPlayer::CCDecoder::CCTrack::operator==(const NuPlayer::CCDecoder::CCTrack& rhs) const { 565 return compare(rhs) == 0; 566 } 567 568 bool NuPlayer::CCDecoder::CCTrack::operator!=(const NuPlayer::CCDecoder::CCTrack& rhs) const { 569 return compare(rhs) != 0; 570 } 571 572 } // namespace android 573 574
