/*
* 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
snprintf(tmp, sizeof(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
snprintf(tmp, sizeof(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
snprintf(tmp, sizeof(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
snprintf(tmp, sizeof(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)
snprintf(tmp, sizeof(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)
snprintf(tmp, sizeof(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)
snprintf(tmp, sizeof(tmp), "[%d]PAC: %02x %02x", cc->mType, cc->mData1, cc->mData2);
} else {
snprintf(tmp, sizeof(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> ¬ify)
: 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);
if (payload_size > SIZE_MAX / 8
|| !br.atLeastNumBitsLeft(payload_size * 8)) {
ALOGV("Malformed SEI payload");
break;
}
// 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