media/libmediaplayerservice/nuplayer/NuPlayerCCDecoder.cpp - third_party/android/platform/frameworks/av - Git at Google

 /*
  * Copyright 2014 The Android Open Source Project
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 //#define LOG_NDEBUG 0
 #define LOG_TAG "NuPlayerCCDecoder"
 #include <utils/Log.h>
 #include <inttypes.h>

 #include "avc_utils.h"
 #include "NuPlayerCCDecoder.h"

 #include <media/stagefright/foundation/ABitReader.h>
 #include <media/stagefright/foundation/ABuffer.h>
 #include <media/stagefright/foundation/ADebug.h>
 #include <media/stagefright/foundation/AMessage.h>
 #include <media/stagefright/MediaDefs.h>

 namespace android {

 // In CEA-708B, the maximum bandwidth of CC is set to 9600bps.
 static const size_t kMaxBandwithSizeBytes = 9600 / 8;

 struct CCData {
     CCData(uint8_t type, uint8_t data1, uint8_t data2)
         : mType(type), mData1(data1), mData2(data2) {
     }
     bool getChannel(size_t *channel) const {
         if (mData1 >= 0x10 && mData1 <= 0x1f) {
             *channel = (mData1 >= 0x18 ? 1 : 0) + (mType ? 2 : 0);
             return true;
         }
         return false;
     }

     uint8_t mType;
     uint8_t mData1;
     uint8_t mData2;
 };

 static bool isNullPad(CCData *cc) {
     return cc->mData1 < 0x10 && cc->mData2 < 0x10;
 }

 static void dumpBytePair(const sp<ABuffer> &ccBuf) __attribute__ ((unused));
 static void dumpBytePair(const sp<ABuffer> &ccBuf) {
     size_t offset = 0;
     AString out;

     while (offset < ccBuf->size()) {
         char tmp[128];

         CCData *cc = (CCData *) (ccBuf->data() + offset);

         if (isNullPad(cc)) {
             // 1 null pad or XDS metadata, ignore
             offset += sizeof(CCData);
             continue;
         }

         if (cc->mData1 >= 0x20 && cc->mData1 <= 0x7f) {
             // 2 basic chars
             sprintf(tmp, "[%d]Basic: %c %c", cc->mType, cc->mData1, cc->mData2);
         } else if ((cc->mData1 == 0x11 || cc->mData1 == 0x19)
                  && cc->mData2 >= 0x30 && cc->mData2 <= 0x3f) {
             // 1 special char
             sprintf(tmp, "[%d]Special: %02x %02x", cc->mType, cc->mData1, cc->mData2);
         } else if ((cc->mData1 == 0x12 || cc->mData1 == 0x1A)
                  && cc->mData2 >= 0x20 && cc->mData2 <= 0x3f){
             // 1 Spanish/French char
             sprintf(tmp, "[%d]Spanish: %02x %02x", cc->mType, cc->mData1, cc->mData2);
         } else if ((cc->mData1 == 0x13 || cc->mData1 == 0x1B)
                  && cc->mData2 >= 0x20 && cc->mData2 <= 0x3f){
             // 1 Portuguese/German/Danish char
             sprintf(tmp, "[%d]German: %02x %02x", cc->mType, cc->mData1, cc->mData2);
         } else if ((cc->mData1 == 0x11 || cc->mData1 == 0x19)
                  && cc->mData2 >= 0x20 && cc->mData2 <= 0x2f){
             // Mid-Row Codes (Table 69)
             sprintf(tmp, "[%d]Mid-row: %02x %02x", cc->mType, cc->mData1, cc->mData2);
         } else if (((cc->mData1 == 0x14 || cc->mData1 == 0x1c)
                   && cc->mData2 >= 0x20 && cc->mData2 <= 0x2f)
                   ||
                    ((cc->mData1 == 0x17 || cc->mData1 == 0x1f)
                   && cc->mData2 >= 0x21 && cc->mData2 <= 0x23)){
             // Misc Control Codes (Table 70)
             sprintf(tmp, "[%d]Ctrl: %02x %02x", cc->mType, cc->mData1, cc->mData2);
         } else if ((cc->mData1 & 0x70) == 0x10
                 && (cc->mData2 & 0x40) == 0x40
                 && ((cc->mData1 & 0x07) || !(cc->mData2 & 0x20)) ) {
             // Preamble Address Codes (Table 71)
             sprintf(tmp, "[%d]PAC: %02x %02x", cc->mType, cc->mData1, cc->mData2);
         } else {
             sprintf(tmp, "[%d]Invalid: %02x %02x", cc->mType, cc->mData1, cc->mData2);
         }

         if (out.size() > 0) {
             out.append(", ");
         }

         out.append(tmp);

         offset += sizeof(CCData);
     }

     ALOGI("%s", out.c_str());
 }

 NuPlayer::CCDecoder::CCDecoder(const sp<AMessage> &notify)
     : mNotify(notify),
       mSelectedTrack(-1),
       mDTVCCPacket(new ABuffer(kMaxBandwithSizeBytes)) {
     mDTVCCPacket->setRange(0, 0);

     // In CEA-608, streams from packets which have the value 0 of cc_type contain CC1 and CC2, and
     // streams from packets which have the value 1 of cc_type contain CC3 and CC4.
     // The following array indicates the current transmitting channels for each value of cc_type.
     mLine21Channels[0] = 0; // CC1
     mLine21Channels[1] = 2; // CC3
 }

 size_t NuPlayer::CCDecoder::getTrackCount() const {
     return mTracks.size();
 }

 sp<AMessage> NuPlayer::CCDecoder::getTrackInfo(size_t index) const {
     if (!isTrackValid(index)) {
         return NULL;
     }

     sp<AMessage> format = new AMessage();

     CCTrack track = mTracks[index];

     format->setInt32("type", MEDIA_TRACK_TYPE_SUBTITLE);
     format->setString("language", "und");

     switch (track.mTrackType) {
         case kTrackTypeCEA608:
             format->setString("mime", MEDIA_MIMETYPE_TEXT_CEA_608);
             break;
         case kTrackTypeCEA708:
             format->setString("mime", MEDIA_MIMETYPE_TEXT_CEA_708);
             break;
         default:
             ALOGE("Unknown track type: %d", track.mTrackType);
             return NULL;
     }

     // For CEA-608 CC1, field 0 channel 0
     bool isDefaultAuto = track.mTrackType == kTrackTypeCEA608
             && track.mTrackChannel == 0;
     // For CEA-708, Primary Caption Service.
     bool isDefaultOnly = track.mTrackType == kTrackTypeCEA708
             && track.mTrackChannel == 1;
     format->setInt32("auto", isDefaultAuto);
     format->setInt32("default", isDefaultAuto || isDefaultOnly);
     format->setInt32("forced", 0);

     return format;
 }

 status_t NuPlayer::CCDecoder::selectTrack(size_t index, bool select) {
     if (!isTrackValid(index)) {
         return BAD_VALUE;
     }

     if (select) {
         if (mSelectedTrack == (ssize_t)index) {
             ALOGE("track %zu already selected", index);
             return BAD_VALUE;
         }
         ALOGV("selected track %zu", index);
         mSelectedTrack = index;
     } else {
         if (mSelectedTrack != (ssize_t)index) {
             ALOGE("track %zu is not selected", index);
             return BAD_VALUE;
         }
         ALOGV("unselected track %zu", index);
         mSelectedTrack = -1;
     }

     // Clear the previous track payloads
     mCCMap.clear();

     return OK;
 }

 bool NuPlayer::CCDecoder::isSelected() const {
     return mSelectedTrack >= 0 && mSelectedTrack < (int32_t)getTrackCount();
 }

 bool NuPlayer::CCDecoder::isTrackValid(size_t index) const {
     return index < getTrackCount();
 }

 // returns true if a new CC track is found
 bool NuPlayer::CCDecoder::extractFromSEI(const sp<ABuffer> &accessUnit) {
     sp<ABuffer> sei;
     if (!accessUnit->meta()->findBuffer("sei", &sei) || sei == NULL) {
         return false;
     }

     int64_t timeUs;
     CHECK(accessUnit->meta()->findInt64("timeUs", &timeUs));

     bool trackAdded = false;

     const NALPosition *nal = (NALPosition *)sei->data();

     for (size_t i = 0; i < sei->size() / sizeof(NALPosition); ++i, ++nal) {
         trackAdded |= parseSEINalUnit(
                 timeUs, accessUnit->data() + nal->nalOffset, nal->nalSize);
     }

     return trackAdded;
 }

 // returns true if a new CC track is found
 bool NuPlayer::CCDecoder::parseSEINalUnit(int64_t timeUs, const uint8_t *data, size_t size) {
     unsigned nalType = data[0] & 0x1f;

     // the buffer should only have SEI in it
     if (nalType != 6) {
         return false;
     }

     bool trackAdded = false;
     NALBitReader br(data + 1, size - 1);

     // sei_message()
     while (br.atLeastNumBitsLeft(16)) { // at least 16-bit for sei_message()
         uint32_t payload_type = 0;
         size_t payload_size = 0;
         uint8_t last_byte;

         do {
             last_byte = br.getBits(8);
             payload_type += last_byte;
         } while (last_byte == 0xFF);

         do {
             last_byte = br.getBits(8);
             payload_size += last_byte;
         } while (last_byte == 0xFF);

         // sei_payload()
         if (payload_type == 4) {
             bool isCC = false;
             if (payload_size > 1 + 2 + 4 + 1) {
                 // user_data_registered_itu_t_t35()

                 // ATSC A/72: 6.4.2
                 uint8_t itu_t_t35_country_code = br.getBits(8);
                 uint16_t itu_t_t35_provider_code = br.getBits(16);
                 uint32_t user_identifier = br.getBits(32);
                 uint8_t user_data_type_code = br.getBits(8);

                 payload_size -= 1 + 2 + 4 + 1;

                 isCC = itu_t_t35_country_code == 0xB5
                         && itu_t_t35_provider_code == 0x0031
                         && user_identifier == 'GA94'
                         && user_data_type_code == 0x3;
             }

             if (isCC && payload_size > 2) {
                 trackAdded |= parseMPEGCCData(timeUs, br.data(), br.numBitsLeft() / 8);
             } else {
                 ALOGV("Malformed SEI payload type 4");
             }
         } else {
             ALOGV("Unsupported SEI payload type %d", payload_type);
         }

         // skipping remaining bits of this payload
         br.skipBits(payload_size * 8);
     }

     return trackAdded;
 }

 // returns true if a new CC track is found
 bool NuPlayer::CCDecoder::extractFromMPEGUserData(const sp<ABuffer> &accessUnit) {
     sp<ABuffer> mpegUserData;
     if (!accessUnit->meta()->findBuffer("mpegUserData", &mpegUserData)
             || mpegUserData == NULL) {
         return false;
     }

     int64_t timeUs;
     CHECK(accessUnit->meta()->findInt64("timeUs", &timeUs));

     bool trackAdded = false;

     const size_t *userData = (size_t *)mpegUserData->data();

     for (size_t i = 0; i < mpegUserData->size() / sizeof(size_t); ++i) {
         trackAdded |= parseMPEGUserDataUnit(
                 timeUs, accessUnit->data() + userData[i], accessUnit->size() - userData[i]);
     }

     return trackAdded;
 }

 // returns true if a new CC track is found
 bool NuPlayer::CCDecoder::parseMPEGUserDataUnit(int64_t timeUs, const uint8_t *data, size_t size) {
     ABitReader br(data + 4, 5);

     uint32_t user_identifier = br.getBits(32);
     uint8_t user_data_type = br.getBits(8);

     if (user_identifier == 'GA94' && user_data_type == 0x3) {
         return parseMPEGCCData(timeUs, data + 9, size - 9);
     }

     return false;
 }

 // returns true if a new CC track is found
 bool NuPlayer::CCDecoder::parseMPEGCCData(int64_t timeUs, const uint8_t *data, size_t size) {
     bool trackAdded = false;

     // MPEG_cc_data()
     // ATSC A/53 Part 4: 6.2.3.1
     ABitReader br(data, size);

     if (br.numBitsLeft() <= 16) {
         return false;
     }

     br.skipBits(1);
     bool process_cc_data_flag = br.getBits(1);
     br.skipBits(1);
     size_t cc_count = br.getBits(5);
     br.skipBits(8);

     if (!process_cc_data_flag || 3 * 8 * cc_count >= br.numBitsLeft()) {
         return false;
     }

     sp<ABuffer> line21CCBuf = NULL;

     for (size_t i = 0; i < cc_count; ++i) {
         br.skipBits(5);
         bool cc_valid = br.getBits(1);
         uint8_t cc_type = br.getBits(2);

         if (cc_valid) {
             if (cc_type == 3) {
                 if (mDTVCCPacket->size() > 0) {
                     trackAdded |= parseDTVCCPacket(
                             timeUs, mDTVCCPacket->data(), mDTVCCPacket->size());
                     mDTVCCPacket->setRange(0, 0);
                 }
                 memcpy(mDTVCCPacket->data() + mDTVCCPacket->size(), br.data(), 2);
                 mDTVCCPacket->setRange(0, mDTVCCPacket->size() + 2);
                 br.skipBits(16);
             } else if (mDTVCCPacket->size() > 0 && cc_type == 2) {
                 memcpy(mDTVCCPacket->data() + mDTVCCPacket->size(), br.data(), 2);
                 mDTVCCPacket->setRange(0, mDTVCCPacket->size() + 2);
                 br.skipBits(16);
             } else if (cc_type == 0 || cc_type == 1) {
                 uint8_t cc_data_1 = br.getBits(8) & 0x7f;
                 uint8_t cc_data_2 = br.getBits(8) & 0x7f;

                 CCData cc(cc_type, cc_data_1, cc_data_2);

                 if (isNullPad(&cc)) {
                     continue;
                 }

                 size_t channel;
                 if (cc.getChannel(&channel)) {
                     mLine21Channels[cc_type] = channel;

                     // create a new track if it does not exist.
                     getTrackIndex(kTrackTypeCEA608, channel, &trackAdded);
                 }

                 if (isSelected() && mTracks[mSelectedTrack].mTrackType == kTrackTypeCEA608
                         && mTracks[mSelectedTrack].mTrackChannel == mLine21Channels[cc_type]) {
                     if (line21CCBuf == NULL) {
                         line21CCBuf = new ABuffer((cc_count - i) * sizeof(CCData));
                         line21CCBuf->setRange(0, 0);
                     }
                     memcpy(line21CCBuf->data() + line21CCBuf->size(), &cc, sizeof(cc));
                     line21CCBuf->setRange(0, line21CCBuf->size() + sizeof(CCData));
                 }
             } else {
                 br.skipBits(16);
             }
         } else {
             if ((cc_type == 3 || cc_type == 2) && mDTVCCPacket->size() > 0) {
                 trackAdded |= parseDTVCCPacket(timeUs, mDTVCCPacket->data(), mDTVCCPacket->size());
                 mDTVCCPacket->setRange(0, 0);
             }
             br.skipBits(16);
         }
     }

     if (isSelected() && mTracks[mSelectedTrack].mTrackType == kTrackTypeCEA608
             && line21CCBuf != NULL && line21CCBuf->size() > 0) {
         mCCMap.add(timeUs, line21CCBuf);
     }

     return trackAdded;
 }

 // returns true if a new CC track is found
 bool NuPlayer::CCDecoder::parseDTVCCPacket(int64_t timeUs, const uint8_t *data, size_t size) {
     // CEA-708B 5 DTVCC Packet Layer.
     ABitReader br(data, size);
     br.skipBits(2);

     size_t packet_size = br.getBits(6);
     if (packet_size == 0) packet_size = 64;
     packet_size *= 2;

     if (size != packet_size) {
         return false;
     }

     bool trackAdded = false;

     while (br.numBitsLeft() >= 16) {
         // CEA-708B Figure 5 and 6.
         uint8_t service_number = br.getBits(3);
         size_t block_size = br.getBits(5);

         if (service_number == 64) {
             br.skipBits(2);
             service_number = br.getBits(6);

             if (service_number < 64) {
                 return trackAdded;
             }
         }

         if (br.numBitsLeft() < block_size * 8) {
             return trackAdded;
         }

         if (block_size > 0) {
             size_t trackIndex = getTrackIndex(kTrackTypeCEA708, service_number, &trackAdded);
             if (mSelectedTrack == (ssize_t)trackIndex) {
                 sp<ABuffer> ccPacket = new ABuffer(block_size);
                 memcpy(ccPacket->data(), br.data(), block_size);
                 mCCMap.add(timeUs, ccPacket);
             }
         }
         br.skipBits(block_size * 8);
     }

     return trackAdded;
 }

 // return the track index for a given type and channel.
 // if the track does not exist, creates a new one.
 size_t NuPlayer::CCDecoder::getTrackIndex(
         int32_t trackType, size_t channel, bool *trackAdded) {
     CCTrack track(trackType, channel);
     ssize_t index = mTrackIndices.indexOfKey(track);

     if (index < 0) {
         // A new track is added.
         index = mTracks.size();
         mTrackIndices.add(track, index);
         mTracks.add(track);
         *trackAdded = true;
         return index;
     }

     return mTrackIndices.valueAt(index);
 }

 void NuPlayer::CCDecoder::decode(const sp<ABuffer> &accessUnit) {
     if (extractFromMPEGUserData(accessUnit) || extractFromSEI(accessUnit)) {
         sp<AMessage> msg = mNotify->dup();
         msg->setInt32("what", kWhatTrackAdded);
         msg->post();
     }
     // TODO: extract CC from other sources
 }

 void NuPlayer::CCDecoder::display(int64_t timeUs) {
     if (!isSelected()) {
         return;
     }

     ssize_t index = mCCMap.indexOfKey(timeUs);
     if (index < 0) {
         ALOGV("cc for timestamp %" PRId64 " not found", timeUs);
         return;
     }

     sp<ABuffer> ccBuf;

     if (index == 0) {
         ccBuf = mCCMap.valueAt(index);
     } else {
         size_t size = 0;

         for (ssize_t i = 0; i <= index; ++i) {
             size += mCCMap.valueAt(i)->size();
         }

         ccBuf = new ABuffer(size);
         ccBuf->setRange(0, 0);

         for (ssize_t i = 0; i <= index; ++i) {
             sp<ABuffer> buf = mCCMap.valueAt(i);
             memcpy(ccBuf->data() + ccBuf->size(), buf->data(), buf->size());
             ccBuf->setRange(0, ccBuf->size() + buf->size());
         }
     }

     if (ccBuf->size() > 0) {
 #if 0
         dumpBytePair(ccBuf);
 #endif

         ccBuf->meta()->setInt32("trackIndex", mSelectedTrack);
         ccBuf->meta()->setInt64("timeUs", timeUs);
         ccBuf->meta()->setInt64("durationUs", 0ll);

         sp<AMessage> msg = mNotify->dup();
         msg->setInt32("what", kWhatClosedCaptionData);
         msg->setBuffer("buffer", ccBuf);
         msg->post();
     }

     // remove all entries before timeUs
     mCCMap.removeItemsAt(0, index + 1);
 }

 void NuPlayer::CCDecoder::flush() {
     mCCMap.clear();
     mDTVCCPacket->setRange(0, 0);
 }

 int32_t NuPlayer::CCDecoder::CCTrack::compare(const NuPlayer::CCDecoder::CCTrack& rhs) const {
     int32_t cmp = mTrackType - rhs.mTrackType;
     if (cmp != 0) return cmp;
     return mTrackChannel - rhs.mTrackChannel;
 }

 bool NuPlayer::CCDecoder::CCTrack::operator<(const NuPlayer::CCDecoder::CCTrack& rhs) const {
     return compare(rhs) < 0;
 }

 bool NuPlayer::CCDecoder::CCTrack::operator==(const NuPlayer::CCDecoder::CCTrack& rhs) const {
     return compare(rhs) == 0;
 }

 bool NuPlayer::CCDecoder::CCTrack::operator!=(const NuPlayer::CCDecoder::CCTrack& rhs) const {
     return compare(rhs) != 0;
 }

 }  // namespace android
	/*
	* Copyright 2014 The Android Open Source Project
	*
	* Licensed under the Apache License, Version 2.0 (the "License");
	* you may not use this file except in compliance with the License.
	* You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	//#define LOG_NDEBUG 0
	#define LOG_TAG "NuPlayerCCDecoder"
	#include <utils/Log.h>
	#include <inttypes.h>

	#include "avc_utils.h"
	#include "NuPlayerCCDecoder.h"

	#include <media/stagefright/foundation/ABitReader.h>
	#include <media/stagefright/foundation/ABuffer.h>
	#include <media/stagefright/foundation/ADebug.h>
	#include <media/stagefright/foundation/AMessage.h>
	#include <media/stagefright/MediaDefs.h>

	namespace android {

	// In CEA-708B, the maximum bandwidth of CC is set to 9600bps.
	static const size_t kMaxBandwithSizeBytes = 9600 / 8;

	struct CCData {
	CCData(uint8_t type, uint8_t data1, uint8_t data2)
	: mType(type), mData1(data1), mData2(data2) {
	}
	bool getChannel(size_t *channel) const {
	if (mData1 >= 0x10 && mData1 <= 0x1f) {
	*channel = (mData1 >= 0x18 ? 1 : 0) + (mType ? 2 : 0);
	return true;
	}
	return false;
	}

	uint8_t mType;
	uint8_t mData1;
	uint8_t mData2;
	};

	static bool isNullPad(CCData *cc) {
	return cc->mData1 < 0x10 && cc->mData2 < 0x10;
	}

	static void dumpBytePair(const sp<ABuffer> &ccBuf) __attribute__ ((unused));
	static void dumpBytePair(const sp<ABuffer> &ccBuf) {
	size_t offset = 0;
	AString out;

	while (offset < ccBuf->size()) {
	char tmp[128];

	CCData cc = (CCData ) (ccBuf->data() + offset);

	if (isNullPad(cc)) {
	// 1 null pad or XDS metadata, ignore
	offset += sizeof(CCData);
	continue;
	}

	if (cc->mData1 >= 0x20 && cc->mData1 <= 0x7f) {
	// 2 basic chars
	sprintf(tmp, "[%d]Basic: %c %c", cc->mType, cc->mData1, cc->mData2);
	} else if ((cc->mData1 == 0x11 \|\| cc->mData1 == 0x19)
	&& cc->mData2 >= 0x30 && cc->mData2 <= 0x3f) {
	// 1 special char
	sprintf(tmp, "[%d]Special: %02x %02x", cc->mType, cc->mData1, cc->mData2);
	} else if ((cc->mData1 == 0x12 \|\| cc->mData1 == 0x1A)
	&& cc->mData2 >= 0x20 && cc->mData2 <= 0x3f){
	// 1 Spanish/French char
	sprintf(tmp, "[%d]Spanish: %02x %02x", cc->mType, cc->mData1, cc->mData2);
	} else if ((cc->mData1 == 0x13 \|\| cc->mData1 == 0x1B)
	&& cc->mData2 >= 0x20 && cc->mData2 <= 0x3f){
	// 1 Portuguese/German/Danish char
	sprintf(tmp, "[%d]German: %02x %02x", cc->mType, cc->mData1, cc->mData2);
	} else if ((cc->mData1 == 0x11 \|\| cc->mData1 == 0x19)
	&& cc->mData2 >= 0x20 && cc->mData2 <= 0x2f){
	// Mid-Row Codes (Table 69)
	sprintf(tmp, "[%d]Mid-row: %02x %02x", cc->mType, cc->mData1, cc->mData2);
	} else if (((cc->mData1 == 0x14 \|\| cc->mData1 == 0x1c)
	&& cc->mData2 >= 0x20 && cc->mData2 <= 0x2f)
	\|\|
	((cc->mData1 == 0x17 \|\| cc->mData1 == 0x1f)
	&& cc->mData2 >= 0x21 && cc->mData2 <= 0x23)){
	// Misc Control Codes (Table 70)
	sprintf(tmp, "[%d]Ctrl: %02x %02x", cc->mType, cc->mData1, cc->mData2);
	} else if ((cc->mData1 & 0x70) == 0x10
	&& (cc->mData2 & 0x40) == 0x40
	&& ((cc->mData1 & 0x07) \|\| !(cc->mData2 & 0x20)) ) {
	// Preamble Address Codes (Table 71)
	sprintf(tmp, "[%d]PAC: %02x %02x", cc->mType, cc->mData1, cc->mData2);
	} else {
	sprintf(tmp, "[%d]Invalid: %02x %02x", cc->mType, cc->mData1, cc->mData2);
	}

	if (out.size() > 0) {
	out.append(", ");
	}

	out.append(tmp);

	offset += sizeof(CCData);
	}

	ALOGI("%s", out.c_str());
	}

	NuPlayer::CCDecoder::CCDecoder(const sp<AMessage> &notify)
	: mNotify(notify),
	mSelectedTrack(-1),
	mDTVCCPacket(new ABuffer(kMaxBandwithSizeBytes)) {
	mDTVCCPacket->setRange(0, 0);

	// In CEA-608, streams from packets which have the value 0 of cc_type contain CC1 and CC2, and
	// streams from packets which have the value 1 of cc_type contain CC3 and CC4.
	// The following array indicates the current transmitting channels for each value of cc_type.
	mLine21Channels[0] = 0; // CC1
	mLine21Channels[1] = 2; // CC3
	}

	size_t NuPlayer::CCDecoder::getTrackCount() const {
	return mTracks.size();
	}

	sp<AMessage> NuPlayer::CCDecoder::getTrackInfo(size_t index) const {
	if (!isTrackValid(index)) {
	return NULL;
	}

	sp<AMessage> format = new AMessage();

	CCTrack track = mTracks[index];

	format->setInt32("type", MEDIA_TRACK_TYPE_SUBTITLE);
	format->setString("language", "und");

	switch (track.mTrackType) {
	case kTrackTypeCEA608:
	format->setString("mime", MEDIA_MIMETYPE_TEXT_CEA_608);
	break;
	case kTrackTypeCEA708:
	format->setString("mime", MEDIA_MIMETYPE_TEXT_CEA_708);
	break;
	default:
	ALOGE("Unknown track type: %d", track.mTrackType);
	return NULL;
	}

	// For CEA-608 CC1, field 0 channel 0
	bool isDefaultAuto = track.mTrackType == kTrackTypeCEA608
	&& track.mTrackChannel == 0;
	// For CEA-708, Primary Caption Service.
	bool isDefaultOnly = track.mTrackType == kTrackTypeCEA708
	&& track.mTrackChannel == 1;
	format->setInt32("auto", isDefaultAuto);
	format->setInt32("default", isDefaultAuto \|\| isDefaultOnly);
	format->setInt32("forced", 0);

	return format;
	}

	status_t NuPlayer::CCDecoder::selectTrack(size_t index, bool select) {
	if (!isTrackValid(index)) {
	return BAD_VALUE;
	}

	if (select) {
	if (mSelectedTrack == (ssize_t)index) {
	ALOGE("track %zu already selected", index);
	return BAD_VALUE;
	}
	ALOGV("selected track %zu", index);
	mSelectedTrack = index;
	} else {
	if (mSelectedTrack != (ssize_t)index) {
	ALOGE("track %zu is not selected", index);
	return BAD_VALUE;
	}
	ALOGV("unselected track %zu", index);
	mSelectedTrack = -1;
	}

	// Clear the previous track payloads
	mCCMap.clear();

	return OK;
	}

	bool NuPlayer::CCDecoder::isSelected() const {
	return mSelectedTrack >= 0 && mSelectedTrack < (int32_t)getTrackCount();
	}

	bool NuPlayer::CCDecoder::isTrackValid(size_t index) const {
	return index < getTrackCount();
	}

	// returns true if a new CC track is found
	bool NuPlayer::CCDecoder::extractFromSEI(const sp<ABuffer> &accessUnit) {
	sp<ABuffer> sei;
	if (!accessUnit->meta()->findBuffer("sei", &sei) \|\| sei == NULL) {
	return false;
	}

	int64_t timeUs;
	CHECK(accessUnit->meta()->findInt64("timeUs", &timeUs));

	bool trackAdded = false;

	const NALPosition nal = (NALPosition )sei->data();

	for (size_t i = 0; i < sei->size() / sizeof(NALPosition); ++i, ++nal) {
	trackAdded \|= parseSEINalUnit(
	timeUs, accessUnit->data() + nal->nalOffset, nal->nalSize);
	}

	return trackAdded;
	}

	// returns true if a new CC track is found
	bool NuPlayer::CCDecoder::parseSEINalUnit(int64_t timeUs, const uint8_t *data, size_t size) {
	unsigned nalType = data[0] & 0x1f;

	// the buffer should only have SEI in it
	if (nalType != 6) {
	return false;
	}

	bool trackAdded = false;
	NALBitReader br(data + 1, size - 1);

	// sei_message()
	while (br.atLeastNumBitsLeft(16)) { // at least 16-bit for sei_message()
	uint32_t payload_type = 0;
	size_t payload_size = 0;
	uint8_t last_byte;

	do {
	last_byte = br.getBits(8);
	payload_type += last_byte;
	} while (last_byte == 0xFF);

	do {
	last_byte = br.getBits(8);
	payload_size += last_byte;
	} while (last_byte == 0xFF);

	// sei_payload()
	if (payload_type == 4) {
	bool isCC = false;
	if (payload_size > 1 + 2 + 4 + 1) {
	// user_data_registered_itu_t_t35()

	// ATSC A/72: 6.4.2
	uint8_t itu_t_t35_country_code = br.getBits(8);
	uint16_t itu_t_t35_provider_code = br.getBits(16);
	uint32_t user_identifier = br.getBits(32);
	uint8_t user_data_type_code = br.getBits(8);

	payload_size -= 1 + 2 + 4 + 1;

	isCC = itu_t_t35_country_code == 0xB5
	&& itu_t_t35_provider_code == 0x0031
	&& user_identifier == 'GA94'
	&& user_data_type_code == 0x3;
	}

	if (isCC && payload_size > 2) {
	trackAdded \|= parseMPEGCCData(timeUs, br.data(), br.numBitsLeft() / 8);
	} else {
	ALOGV("Malformed SEI payload type 4");
	}
	} else {
	ALOGV("Unsupported SEI payload type %d", payload_type);
	}

	// skipping remaining bits of this payload
	br.skipBits(payload_size * 8);
	}

	return trackAdded;
	}

	// returns true if a new CC track is found
	bool NuPlayer::CCDecoder::extractFromMPEGUserData(const sp<ABuffer> &accessUnit) {
	sp<ABuffer> mpegUserData;
	if (!accessUnit->meta()->findBuffer("mpegUserData", &mpegUserData)
	\|\| mpegUserData == NULL) {
	return false;
	}

	int64_t timeUs;
	CHECK(accessUnit->meta()->findInt64("timeUs", &timeUs));

	bool trackAdded = false;

	const size_t userData = (size_t )mpegUserData->data();

	for (size_t i = 0; i < mpegUserData->size() / sizeof(size_t); ++i) {
	trackAdded \|= parseMPEGUserDataUnit(
	timeUs, accessUnit->data() + userData[i], accessUnit->size() - userData[i]);
	}

	return trackAdded;
	}

	// returns true if a new CC track is found
	bool NuPlayer::CCDecoder::parseMPEGUserDataUnit(int64_t timeUs, const uint8_t *data, size_t size) {
	ABitReader br(data + 4, 5);

	uint32_t user_identifier = br.getBits(32);
	uint8_t user_data_type = br.getBits(8);

	if (user_identifier == 'GA94' && user_data_type == 0x3) {
	return parseMPEGCCData(timeUs, data + 9, size - 9);
	}

	return false;
	}

	// returns true if a new CC track is found
	bool NuPlayer::CCDecoder::parseMPEGCCData(int64_t timeUs, const uint8_t *data, size_t size) {
	bool trackAdded = false;

	// MPEG_cc_data()
	// ATSC A/53 Part 4: 6.2.3.1
	ABitReader br(data, size);

	if (br.numBitsLeft() <= 16) {
	return false;
	}

	br.skipBits(1);
	bool process_cc_data_flag = br.getBits(1);
	br.skipBits(1);
	size_t cc_count = br.getBits(5);
	br.skipBits(8);

	if (!process_cc_data_flag \|\| 3 * 8 * cc_count >= br.numBitsLeft()) {
	return false;
	}

	sp<ABuffer> line21CCBuf = NULL;

	for (size_t i = 0; i < cc_count; ++i) {
	br.skipBits(5);
	bool cc_valid = br.getBits(1);
	uint8_t cc_type = br.getBits(2);

	if (cc_valid) {
	if (cc_type == 3) {
	if (mDTVCCPacket->size() > 0) {
	trackAdded \|= parseDTVCCPacket(
	timeUs, mDTVCCPacket->data(), mDTVCCPacket->size());
	mDTVCCPacket->setRange(0, 0);
	}
	memcpy(mDTVCCPacket->data() + mDTVCCPacket->size(), br.data(), 2);
	mDTVCCPacket->setRange(0, mDTVCCPacket->size() + 2);
	br.skipBits(16);
	} else if (mDTVCCPacket->size() > 0 && cc_type == 2) {
	memcpy(mDTVCCPacket->data() + mDTVCCPacket->size(), br.data(), 2);
	mDTVCCPacket->setRange(0, mDTVCCPacket->size() + 2);
	br.skipBits(16);
	} else if (cc_type == 0 \|\| cc_type == 1) {
	uint8_t cc_data_1 = br.getBits(8) & 0x7f;
	uint8_t cc_data_2 = br.getBits(8) & 0x7f;

	CCData cc(cc_type, cc_data_1, cc_data_2);

	if (isNullPad(&cc)) {
	continue;
	}

	size_t channel;
	if (cc.getChannel(&channel)) {
	mLine21Channels[cc_type] = channel;

	// create a new track if it does not exist.
	getTrackIndex(kTrackTypeCEA608, channel, &trackAdded);
	}

	if (isSelected() && mTracks[mSelectedTrack].mTrackType == kTrackTypeCEA608
	&& mTracks[mSelectedTrack].mTrackChannel == mLine21Channels[cc_type]) {
	if (line21CCBuf == NULL) {
	line21CCBuf = new ABuffer((cc_count - i) * sizeof(CCData));
	line21CCBuf->setRange(0, 0);
	}
	memcpy(line21CCBuf->data() + line21CCBuf->size(), &cc, sizeof(cc));
	line21CCBuf->setRange(0, line21CCBuf->size() + sizeof(CCData));
	}
	} else {
	br.skipBits(16);
	}
	} else {
	if ((cc_type == 3 \|\| cc_type == 2) && mDTVCCPacket->size() > 0) {
	trackAdded \|= parseDTVCCPacket(timeUs, mDTVCCPacket->data(), mDTVCCPacket->size());
	mDTVCCPacket->setRange(0, 0);
	}
	br.skipBits(16);
	}
	}

	if (isSelected() && mTracks[mSelectedTrack].mTrackType == kTrackTypeCEA608
	&& line21CCBuf != NULL && line21CCBuf->size() > 0) {
	mCCMap.add(timeUs, line21CCBuf);
	}

	return trackAdded;
	}

	// returns true if a new CC track is found
	bool NuPlayer::CCDecoder::parseDTVCCPacket(int64_t timeUs, const uint8_t *data, size_t size) {
	// CEA-708B 5 DTVCC Packet Layer.
	ABitReader br(data, size);
	br.skipBits(2);

	size_t packet_size = br.getBits(6);
	if (packet_size == 0) packet_size = 64;
	packet_size *= 2;

	if (size != packet_size) {
	return false;
	}

	bool trackAdded = false;

	while (br.numBitsLeft() >= 16) {
	// CEA-708B Figure 5 and 6.
	uint8_t service_number = br.getBits(3);
	size_t block_size = br.getBits(5);

	if (service_number == 64) {
	br.skipBits(2);
	service_number = br.getBits(6);

	if (service_number < 64) {
	return trackAdded;
	}
	}

	if (br.numBitsLeft() < block_size * 8) {
	return trackAdded;
	}

	if (block_size > 0) {
	size_t trackIndex = getTrackIndex(kTrackTypeCEA708, service_number, &trackAdded);
	if (mSelectedTrack == (ssize_t)trackIndex) {
	sp<ABuffer> ccPacket = new ABuffer(block_size);
	memcpy(ccPacket->data(), br.data(), block_size);
	mCCMap.add(timeUs, ccPacket);
	}
	}
	br.skipBits(block_size * 8);
	}

	return trackAdded;
	}

	// return the track index for a given type and channel.
	// if the track does not exist, creates a new one.
	size_t NuPlayer::CCDecoder::getTrackIndex(
	int32_t trackType, size_t channel, bool *trackAdded) {
	CCTrack track(trackType, channel);
	ssize_t index = mTrackIndices.indexOfKey(track);

	if (index < 0) {
	// A new track is added.
	index = mTracks.size();
	mTrackIndices.add(track, index);
	mTracks.add(track);
	*trackAdded = true;
	return index;
	}

	return mTrackIndices.valueAt(index);
	}

	void NuPlayer::CCDecoder::decode(const sp<ABuffer> &accessUnit) {
	if (extractFromMPEGUserData(accessUnit) \|\| extractFromSEI(accessUnit)) {
	sp<AMessage> msg = mNotify->dup();
	msg->setInt32("what", kWhatTrackAdded);
	msg->post();
	}
	// TODO: extract CC from other sources
	}

	void NuPlayer::CCDecoder::display(int64_t timeUs) {
	if (!isSelected()) {
	return;
	}

	ssize_t index = mCCMap.indexOfKey(timeUs);
	if (index < 0) {
	ALOGV("cc for timestamp %" PRId64 " not found", timeUs);
	return;
	}

	sp<ABuffer> ccBuf;

	if (index == 0) {
	ccBuf = mCCMap.valueAt(index);
	} else {
	size_t size = 0;

	for (ssize_t i = 0; i <= index; ++i) {
	size += mCCMap.valueAt(i)->size();
	}

	ccBuf = new ABuffer(size);
	ccBuf->setRange(0, 0);

	for (ssize_t i = 0; i <= index; ++i) {
	sp<ABuffer> buf = mCCMap.valueAt(i);
	memcpy(ccBuf->data() + ccBuf->size(), buf->data(), buf->size());
	ccBuf->setRange(0, ccBuf->size() + buf->size());
	}
	}

	if (ccBuf->size() > 0) {
	#if 0
	dumpBytePair(ccBuf);
	#endif

	ccBuf->meta()->setInt32("trackIndex", mSelectedTrack);
	ccBuf->meta()->setInt64("timeUs", timeUs);
	ccBuf->meta()->setInt64("durationUs", 0ll);

	sp<AMessage> msg = mNotify->dup();
	msg->setInt32("what", kWhatClosedCaptionData);
	msg->setBuffer("buffer", ccBuf);
	msg->post();
	}

	// remove all entries before timeUs
	mCCMap.removeItemsAt(0, index + 1);
	}

	void NuPlayer::CCDecoder::flush() {
	mCCMap.clear();
	mDTVCCPacket->setRange(0, 0);
	}

	int32_t NuPlayer::CCDecoder::CCTrack::compare(const NuPlayer::CCDecoder::CCTrack& rhs) const {
	int32_t cmp = mTrackType - rhs.mTrackType;
	if (cmp != 0) return cmp;
	return mTrackChannel - rhs.mTrackChannel;
	}

	bool NuPlayer::CCDecoder::CCTrack::operator<(const NuPlayer::CCDecoder::CCTrack& rhs) const {
	return compare(rhs) < 0;
	}

	bool NuPlayer::CCDecoder::CCTrack::operator==(const NuPlayer::CCDecoder::CCTrack& rhs) const {
	return compare(rhs) == 0;
	}

	bool NuPlayer::CCDecoder::CCTrack::operator!=(const NuPlayer::CCDecoder::CCTrack& rhs) const {
	return compare(rhs) != 0;
	}

	} // namespace android