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 31namespace android { 32 33// In CEA-708B, the maximum bandwidth of CC is set to 9600bps. 34static const size_t kMaxBandwithSizeBytes = 9600 / 8; 35 36struct 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 53static bool isNullPad(CCData *cc) { 54 return cc->mData1 < 0x10 && cc->mData2 < 0x10; 55} 56 57static void dumpBytePair(const sp<ABuffer> &ccBuf) __attribute__ ((unused)); 58static 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 snprintf(tmp, sizeof(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 snprintf(tmp, sizeof(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 snprintf(tmp, sizeof(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 snprintf(tmp, sizeof(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 snprintf(tmp, sizeof(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 snprintf(tmp, sizeof(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 snprintf(tmp, sizeof(tmp), "[%d]PAC: %02x %02x", cc->mType, cc->mData1, cc->mData2); 104 } else { 105 snprintf(tmp, sizeof(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 120NuPlayer::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 133size_t NuPlayer::CCDecoder::getTrackCount() const { 134 return mTracks.size(); 135} 136 137sp<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 174status_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 201bool NuPlayer::CCDecoder::isSelected() const { 202 return mSelectedTrack >= 0 && mSelectedTrack < (int32_t)getTrackCount(); 203} 204 205bool NuPlayer::CCDecoder::isTrackValid(size_t index) const { 206 return index < getTrackCount(); 207} 208 209// returns true if a new CC track is found 210bool 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 232bool 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 if (payload_size > SIZE_MAX / 8 260 || !br.atLeastNumBitsLeft(payload_size * 8)) { 261 ALOGV("Malformed SEI payload"); 262 break; 263 } 264 265 // sei_payload() 266 if (payload_type == 4) { 267 bool isCC = false; 268 if (payload_size > 1 + 2 + 4 + 1) { 269 // user_data_registered_itu_t_t35() 270 271 // ATSC A/72: 6.4.2 272 uint8_t itu_t_t35_country_code = br.getBits(8); 273 uint16_t itu_t_t35_provider_code = br.getBits(16); 274 uint32_t user_identifier = br.getBits(32); 275 uint8_t user_data_type_code = br.getBits(8); 276 277 payload_size -= 1 + 2 + 4 + 1; 278 279 isCC = itu_t_t35_country_code == 0xB5 280 && itu_t_t35_provider_code == 0x0031 281 && user_identifier == 'GA94' 282 && user_data_type_code == 0x3; 283 } 284 285 if (isCC && payload_size > 2) { 286 trackAdded |= parseMPEGCCData(timeUs, br.data(), br.numBitsLeft() / 8); 287 } else { 288 ALOGV("Malformed SEI payload type 4"); 289 } 290 } else { 291 ALOGV("Unsupported SEI payload type %d", payload_type); 292 } 293 294 // skipping remaining bits of this payload 295 br.skipBits(payload_size * 8); 296 } 297 298 return trackAdded; 299} 300 301// returns true if a new CC track is found 302bool NuPlayer::CCDecoder::extractFromMPEGUserData(const sp<ABuffer> &accessUnit) { 303 sp<ABuffer> mpegUserData; 304 if (!accessUnit->meta()->findBuffer("mpegUserData", &mpegUserData) 305 || mpegUserData == NULL) { 306 return false; 307 } 308 309 int64_t timeUs; 310 CHECK(accessUnit->meta()->findInt64("timeUs", &timeUs)); 311 312 bool trackAdded = false; 313 314 const size_t *userData = (size_t *)mpegUserData->data(); 315 316 for (size_t i = 0; i < mpegUserData->size() / sizeof(size_t); ++i) { 317 trackAdded |= parseMPEGUserDataUnit( 318 timeUs, accessUnit->data() + userData[i], accessUnit->size() - userData[i]); 319 } 320 321 return trackAdded; 322} 323 324// returns true if a new CC track is found 325bool NuPlayer::CCDecoder::parseMPEGUserDataUnit(int64_t timeUs, const uint8_t *data, size_t size) { 326 ABitReader br(data + 4, 5); 327 328 uint32_t user_identifier = br.getBits(32); 329 uint8_t user_data_type = br.getBits(8); 330 331 if (user_identifier == 'GA94' && user_data_type == 0x3) { 332 return parseMPEGCCData(timeUs, data + 9, size - 9); 333 } 334 335 return false; 336} 337 338// returns true if a new CC track is found 339bool NuPlayer::CCDecoder::parseMPEGCCData(int64_t timeUs, const uint8_t *data, size_t size) { 340 bool trackAdded = false; 341 342 // MPEG_cc_data() 343 // ATSC A/53 Part 4: 6.2.3.1 344 ABitReader br(data, size); 345 346 if (br.numBitsLeft() <= 16) { 347 return false; 348 } 349 350 br.skipBits(1); 351 bool process_cc_data_flag = br.getBits(1); 352 br.skipBits(1); 353 size_t cc_count = br.getBits(5); 354 br.skipBits(8); 355 356 if (!process_cc_data_flag || 3 * 8 * cc_count >= br.numBitsLeft()) { 357 return false; 358 } 359 360 sp<ABuffer> line21CCBuf = NULL; 361 362 for (size_t i = 0; i < cc_count; ++i) { 363 br.skipBits(5); 364 bool cc_valid = br.getBits(1); 365 uint8_t cc_type = br.getBits(2); 366 367 if (cc_valid) { 368 if (cc_type == 3) { 369 if (mDTVCCPacket->size() > 0) { 370 trackAdded |= parseDTVCCPacket( 371 timeUs, mDTVCCPacket->data(), mDTVCCPacket->size()); 372 mDTVCCPacket->setRange(0, 0); 373 } 374 memcpy(mDTVCCPacket->data() + mDTVCCPacket->size(), br.data(), 2); 375 mDTVCCPacket->setRange(0, mDTVCCPacket->size() + 2); 376 br.skipBits(16); 377 } else if (mDTVCCPacket->size() > 0 && cc_type == 2) { 378 memcpy(mDTVCCPacket->data() + mDTVCCPacket->size(), br.data(), 2); 379 mDTVCCPacket->setRange(0, mDTVCCPacket->size() + 2); 380 br.skipBits(16); 381 } else if (cc_type == 0 || cc_type == 1) { 382 uint8_t cc_data_1 = br.getBits(8) & 0x7f; 383 uint8_t cc_data_2 = br.getBits(8) & 0x7f; 384 385 CCData cc(cc_type, cc_data_1, cc_data_2); 386 387 if (isNullPad(&cc)) { 388 continue; 389 } 390 391 size_t channel; 392 if (cc.getChannel(&channel)) { 393 mLine21Channels[cc_type] = channel; 394 395 // create a new track if it does not exist. 396 getTrackIndex(kTrackTypeCEA608, channel, &trackAdded); 397 } 398 399 if (isSelected() && mTracks[mSelectedTrack].mTrackType == kTrackTypeCEA608 400 && mTracks[mSelectedTrack].mTrackChannel == mLine21Channels[cc_type]) { 401 if (line21CCBuf == NULL) { 402 line21CCBuf = new ABuffer((cc_count - i) * sizeof(CCData)); 403 line21CCBuf->setRange(0, 0); 404 } 405 memcpy(line21CCBuf->data() + line21CCBuf->size(), &cc, sizeof(cc)); 406 line21CCBuf->setRange(0, line21CCBuf->size() + sizeof(CCData)); 407 } 408 } else { 409 br.skipBits(16); 410 } 411 } else { 412 if ((cc_type == 3 || cc_type == 2) && mDTVCCPacket->size() > 0) { 413 trackAdded |= parseDTVCCPacket(timeUs, mDTVCCPacket->data(), mDTVCCPacket->size()); 414 mDTVCCPacket->setRange(0, 0); 415 } 416 br.skipBits(16); 417 } 418 } 419 420 if (isSelected() && mTracks[mSelectedTrack].mTrackType == kTrackTypeCEA608 421 && line21CCBuf != NULL && line21CCBuf->size() > 0) { 422 mCCMap.add(timeUs, line21CCBuf); 423 } 424 425 return trackAdded; 426} 427 428// returns true if a new CC track is found 429bool NuPlayer::CCDecoder::parseDTVCCPacket(int64_t timeUs, const uint8_t *data, size_t size) { 430 // CEA-708B 5 DTVCC Packet Layer. 431 ABitReader br(data, size); 432 br.skipBits(2); 433 434 size_t packet_size = br.getBits(6); 435 if (packet_size == 0) packet_size = 64; 436 packet_size *= 2; 437 438 if (size != packet_size) { 439 return false; 440 } 441 442 bool trackAdded = false; 443 444 while (br.numBitsLeft() >= 16) { 445 // CEA-708B Figure 5 and 6. 446 uint8_t service_number = br.getBits(3); 447 size_t block_size = br.getBits(5); 448 449 if (service_number == 64) { 450 br.skipBits(2); 451 service_number = br.getBits(6); 452 453 if (service_number < 64) { 454 return trackAdded; 455 } 456 } 457 458 if (br.numBitsLeft() < block_size * 8) { 459 return trackAdded; 460 } 461 462 if (block_size > 0) { 463 size_t trackIndex = getTrackIndex(kTrackTypeCEA708, service_number, &trackAdded); 464 if (mSelectedTrack == (ssize_t)trackIndex) { 465 sp<ABuffer> ccPacket = new ABuffer(block_size); 466 memcpy(ccPacket->data(), br.data(), block_size); 467 mCCMap.add(timeUs, ccPacket); 468 } 469 } 470 br.skipBits(block_size * 8); 471 } 472 473 return trackAdded; 474} 475 476// return the track index for a given type and channel. 477// if the track does not exist, creates a new one. 478size_t NuPlayer::CCDecoder::getTrackIndex( 479 int32_t trackType, size_t channel, bool *trackAdded) { 480 CCTrack track(trackType, channel); 481 ssize_t index = mTrackIndices.indexOfKey(track); 482 483 if (index < 0) { 484 // A new track is added. 485 index = mTracks.size(); 486 mTrackIndices.add(track, index); 487 mTracks.add(track); 488 *trackAdded = true; 489 return index; 490 } 491 492 return mTrackIndices.valueAt(index); 493} 494 495void NuPlayer::CCDecoder::decode(const sp<ABuffer> &accessUnit) { 496 if (extractFromMPEGUserData(accessUnit) || extractFromSEI(accessUnit)) { 497 sp<AMessage> msg = mNotify->dup(); 498 msg->setInt32("what", kWhatTrackAdded); 499 msg->post(); 500 } 501 // TODO: extract CC from other sources 502} 503 504void NuPlayer::CCDecoder::display(int64_t timeUs) { 505 if (!isSelected()) { 506 return; 507 } 508 509 ssize_t index = mCCMap.indexOfKey(timeUs); 510 if (index < 0) { 511 ALOGV("cc for timestamp %" PRId64 " not found", timeUs); 512 return; 513 } 514 515 sp<ABuffer> ccBuf; 516 517 if (index == 0) { 518 ccBuf = mCCMap.valueAt(index); 519 } else { 520 size_t size = 0; 521 522 for (ssize_t i = 0; i <= index; ++i) { 523 size += mCCMap.valueAt(i)->size(); 524 } 525 526 ccBuf = new ABuffer(size); 527 ccBuf->setRange(0, 0); 528 529 for (ssize_t i = 0; i <= index; ++i) { 530 sp<ABuffer> buf = mCCMap.valueAt(i); 531 memcpy(ccBuf->data() + ccBuf->size(), buf->data(), buf->size()); 532 ccBuf->setRange(0, ccBuf->size() + buf->size()); 533 } 534 } 535 536 if (ccBuf->size() > 0) { 537#if 0 538 dumpBytePair(ccBuf); 539#endif 540 541 ccBuf->meta()->setInt32("trackIndex", mSelectedTrack); 542 ccBuf->meta()->setInt64("timeUs", timeUs); 543 ccBuf->meta()->setInt64("durationUs", 0ll); 544 545 sp<AMessage> msg = mNotify->dup(); 546 msg->setInt32("what", kWhatClosedCaptionData); 547 msg->setBuffer("buffer", ccBuf); 548 msg->post(); 549 } 550 551 // remove all entries before timeUs 552 mCCMap.removeItemsAt(0, index + 1); 553} 554 555void NuPlayer::CCDecoder::flush() { 556 mCCMap.clear(); 557 mDTVCCPacket->setRange(0, 0); 558} 559 560int32_t NuPlayer::CCDecoder::CCTrack::compare(const NuPlayer::CCDecoder::CCTrack& rhs) const { 561 int32_t cmp = mTrackType - rhs.mTrackType; 562 if (cmp != 0) return cmp; 563 return mTrackChannel - rhs.mTrackChannel; 564} 565 566bool NuPlayer::CCDecoder::CCTrack::operator<(const NuPlayer::CCDecoder::CCTrack& rhs) const { 567 return compare(rhs) < 0; 568} 569 570bool NuPlayer::CCDecoder::CCTrack::operator==(const NuPlayer::CCDecoder::CCTrack& rhs) const { 571 return compare(rhs) == 0; 572} 573 574bool NuPlayer::CCDecoder::CCTrack::operator!=(const NuPlayer::CCDecoder::CCTrack& rhs) const { 575 return compare(rhs) != 0; 576} 577 578} // namespace android 579 580