1 files changed, 241 insertions, 48 deletions

diff --git a/media/libstagefright/mpeg2ts/ATSParser.cpp b/media/libstagefright/mpeg2ts/ATSParser.cpp
index 482ccff..0a868bc 100644
--- a/media/libstagefright/mpeg2ts/ATSParser.cpp
+++ b/media/libstagefright/mpeg2ts/ATSParser.cpp
@@ -35,6 +35,7 @@
 #include <media/stagefright/Utils.h>
 #include <media/IStreamSource.h>
 #include <utils/KeyedVector.h>
+#include <utils/Vector.h>
 
 #include <inttypes.h>
 
@@ -47,7 +48,8 @@ namespace android {
 static const size_t kTSPacketSize = 188;
 
 struct ATSParser::Program : public RefBase {
-    Program(ATSParser *parser, unsigned programNumber, unsigned programMapPID);
+    Program(ATSParser *parser, unsigned programNumber, unsigned programMapPID,
+            int64_t lastRecoveredPTS);
 
     bool parsePSISection(
             unsigned pid, ABitReader *br, status_t *err);
@@ -86,14 +88,22 @@ struct ATSParser::Program : public RefBase {
     }
 
 private:
+    struct StreamInfo {
+        unsigned mType;
+        unsigned mPID;
+    };
+
     ATSParser *mParser;
     unsigned mProgramNumber;
     unsigned mProgramMapPID;
     KeyedVector<unsigned, sp<Stream> > mStreams;
     bool mFirstPTSValid;
     uint64_t mFirstPTS;
+    int64_t mLastRecoveredPTS;
 
     status_t parseProgramMap(ABitReader *br);
+    int64_t recoverPTS(uint64_t PTS_33bit);
+    bool switchPIDs(const Vector<StreamInfo> &infos);
 
     DISALLOW_EVIL_CONSTRUCTORS(Program);
 };
@@ -157,10 +167,12 @@ struct ATSParser::PSISection : public RefBase {
     PSISection();
 
     status_t append(const void *data, size_t size);
+    void setSkipBytes(uint8_t skip);
     void clear();
 
     bool isComplete() const;
     bool isEmpty() const;
+    bool isCRCOkay() const;
 
     const uint8_t *data() const;
     size_t size() const;
@@ -170,6 +182,8 @@ protected:
 
 private:
     sp<ABuffer> mBuffer;
+    uint8_t mSkipBytes;
+    static uint32_t CRC_TABLE[];
 
     DISALLOW_EVIL_CONSTRUCTORS(PSISection);
 };
@@ -177,12 +191,14 @@ private:
 ////////////////////////////////////////////////////////////////////////////////
 
 ATSParser::Program::Program(
-        ATSParser *parser, unsigned programNumber, unsigned programMapPID)
+        ATSParser *parser, unsigned programNumber, unsigned programMapPID,
+        int64_t lastRecoveredPTS)
     : mParser(parser),
       mProgramNumber(programNumber),
       mProgramMapPID(programMapPID),
       mFirstPTSValid(false),
-      mFirstPTS(0) {
+      mFirstPTS(0),
+      mLastRecoveredPTS(lastRecoveredPTS) {
     ALOGV("new program number %u", programNumber);
 }
 
@@ -237,10 +253,71 @@ void ATSParser::Program::signalEOS(status_t finalResult) {
     }
 }
 
-struct StreamInfo {
-    unsigned mType;
-    unsigned mPID;
-};
+bool ATSParser::Program::switchPIDs(const Vector<StreamInfo> &infos) {
+    bool success = false;
+
+    if (mStreams.size() == infos.size()) {
+        // build type->PIDs map for old and new mapping
+        size_t i;
+        KeyedVector<int32_t, Vector<int32_t> > oldType2PIDs, newType2PIDs;
+        for (i = 0; i < mStreams.size(); ++i) {
+            ssize_t index = oldType2PIDs.indexOfKey(mStreams[i]->type());
+            if (index < 0) {
+                oldType2PIDs.add(mStreams[i]->type(), Vector<int32_t>());
+            }
+            oldType2PIDs.editValueFor(mStreams[i]->type()).push_back(mStreams[i]->pid());
+        }
+        for (i = 0; i < infos.size(); ++i) {
+            ssize_t index = newType2PIDs.indexOfKey(infos[i].mType);
+            if (index < 0) {
+                newType2PIDs.add(infos[i].mType, Vector<int32_t>());
+            }
+            newType2PIDs.editValueFor(infos[i].mType).push_back(infos[i].mPID);
+        }
+
+        // we can recover if the number of streams for each type hasn't changed
+        if (oldType2PIDs.size() == newType2PIDs.size()) {
+            success = true;
+            for (i = 0; i < oldType2PIDs.size(); ++i) {
+                // KeyedVector is sorted, we just compare key and size of each index
+                if (oldType2PIDs.keyAt(i) != newType2PIDs.keyAt(i)
+                        || oldType2PIDs[i].size() != newType2PIDs[i].size()) {
+                     success = false;
+                     break;
+                }
+            }
+        }
+
+        if (success) {
+            // save current streams to temp
+            KeyedVector<int32_t, sp<Stream> > temp;
+            for (i = 0; i < mStreams.size(); ++i) {
+                 temp.add(mStreams.keyAt(i), mStreams.editValueAt(i));
+            }
+
+            mStreams.clear();
+            for (i = 0; i < temp.size(); ++i) {
+                // The two checks below shouldn't happen,
+                // we already checked above the stream count matches
+                ssize_t index = newType2PIDs.indexOfKey(temp[i]->type());
+                CHECK(index >= 0);
+                Vector<int32_t> &newPIDs = newType2PIDs.editValueAt(index);
+                CHECK(newPIDs.size() > 0);
+
+                // get the next PID for temp[i]->type() in the new PID map
+                Vector<int32_t>::iterator it = newPIDs.begin();
+
+                // change the PID of the stream, and add it back
+                temp.editValueAt(i)->setPID(*it);
+                mStreams.add(temp[i]->pid(), temp.editValueAt(i));
+
+                // removed the used PID
+                newPIDs.erase(it);
+            }
+        }
+    }
+    return success;
+}
 
 status_t ATSParser::Program::parseProgramMap(ABitReader *br) {
     unsigned table_id = br->getBits(8);
@@ -369,39 +446,8 @@ status_t ATSParser::Program::parseProgramMap(ABitReader *br) {
         }
 #endif
 
-        // The only case we can recover from is if we have two streams
-        // and they switched PIDs.
-
-        bool success = false;
-
-        if (mStreams.size() == 2 && infos.size() == 2) {
-            const StreamInfo &info1 = infos.itemAt(0);
-            const StreamInfo &info2 = infos.itemAt(1);
-
-            sp<Stream> s1 = mStreams.editValueAt(0);
-            sp<Stream> s2 = mStreams.editValueAt(1);
-
-            bool caseA =
-                info1.mPID == s1->pid() && info1.mType == s2->type()
-                    && info2.mPID == s2->pid() && info2.mType == s1->type();
-
-            bool caseB =
-                info1.mPID == s2->pid() && info1.mType == s1->type()
-                    && info2.mPID == s1->pid() && info2.mType == s2->type();
-
-            if (caseA || caseB) {
-                unsigned pid1 = s1->pid();
-                unsigned pid2 = s2->pid();
-                s1->setPID(pid2);
-                s2->setPID(pid1);
-
-                mStreams.clear();
-                mStreams.add(s1->pid(), s1);
-                mStreams.add(s2->pid(), s2);
-
-                success = true;
-            }
-        }
+        // we can recover if number of streams for each type remain the same
+        bool success = switchPIDs(infos);
 
         if (!success) {
             ALOGI("Stream PIDs changed and we cannot recover.");
@@ -425,6 +471,32 @@ status_t ATSParser::Program::parseProgramMap(ABitReader *br) {
     return OK;
 }
 
+int64_t ATSParser::Program::recoverPTS(uint64_t PTS_33bit) {
+    // We only have the lower 33-bit of the PTS. It could overflow within a
+    // reasonable amount of time. To handle the wrap-around, use fancy math
+    // to get an extended PTS that is within [-0xffffffff, 0xffffffff]
+    // of the latest recovered PTS.
+    if (mLastRecoveredPTS < 0ll) {
+        // Use the original 33bit number for 1st frame, the reason is that
+        // if 1st frame wraps to negative that's far away from 0, we could
+        // never start. Only start wrapping around from 2nd frame.
+        mLastRecoveredPTS = static_cast<int64_t>(PTS_33bit);
+    } else {
+        mLastRecoveredPTS = static_cast<int64_t>(
+                ((mLastRecoveredPTS - PTS_33bit + 0x100000000ll)
+                & 0xfffffffe00000000ull) | PTS_33bit);
+        // We start from 0, but recovered PTS could be slightly below 0.
+        // Clamp it to 0 as rest of the pipeline doesn't take negative pts.
+        // (eg. video is read first and starts at 0, but audio starts at 0xfffffff0)
+        if (mLastRecoveredPTS < 0ll) {
+            ALOGI("Clamping negative recovered PTS (%" PRId64 ") to 0", mLastRecoveredPTS);
+            mLastRecoveredPTS = 0ll;
+        }
+    }
+
+    return mLastRecoveredPTS;
+}
+
 sp<MediaSource> ATSParser::Program::getSource(SourceType type) {
     size_t index = (type == AUDIO) ? 0 : 0;
 
@@ -455,6 +527,8 @@ bool ATSParser::Program::hasSource(SourceType type) const {
 }
 
 int64_t ATSParser::Program::convertPTSToTimestamp(uint64_t PTS) {
+    PTS = recoverPTS(PTS);
+
     if (!(mParser->mFlags & TS_TIMESTAMPS_ARE_ABSOLUTE)) {
         if (!mFirstPTSValid) {
             mFirstPTSValid = true;
@@ -969,6 +1043,7 @@ ATSParser::ATSParser(uint32_t flags)
       mAbsoluteTimeAnchorUs(-1ll),
       mTimeOffsetValid(false),
       mTimeOffsetUs(0ll),
+      mLastRecoveredPTS(-1ll),
       mNumTSPacketsParsed(0),
       mNumPCRs(0) {
     mPSISections.add(0 /* PID */, new PSISection);
@@ -987,11 +1062,21 @@ status_t ATSParser::feedTSPacket(const void *data, size_t size) {
 void ATSParser::signalDiscontinuity(
         DiscontinuityType type, const sp<AMessage> &extra) {
     int64_t mediaTimeUs;
-    if ((type & DISCONTINUITY_TIME)
-            && extra != NULL
-            && extra->findInt64(
-                IStreamListener::kKeyMediaTimeUs, &mediaTimeUs)) {
-        mAbsoluteTimeAnchorUs = mediaTimeUs;
+    if ((type & DISCONTINUITY_TIME) && extra != NULL) {
+        if (extra->findInt64(IStreamListener::kKeyMediaTimeUs, &mediaTimeUs)) {
+            mAbsoluteTimeAnchorUs = mediaTimeUs;
+        }
+        if ((mFlags & TS_TIMESTAMPS_ARE_ABSOLUTE)
+                && extra->findInt64(
+                    IStreamListener::kKeyRecentMediaTimeUs, &mediaTimeUs)) {
+            if (mAbsoluteTimeAnchorUs >= 0ll) {
+                mediaTimeUs -= mAbsoluteTimeAnchorUs;
+            }
+            if (mTimeOffsetValid) {
+                mediaTimeUs -= mTimeOffsetUs;
+            }
+            mLastRecoveredPTS = (mediaTimeUs * 9) / 100;
+        }
     } else if (type == DISCONTINUITY_ABSOLUTE_TIME) {
         int64_t timeUs;
         CHECK(extra->findInt64("timeUs", &timeUs));
@@ -1075,7 +1160,7 @@ void ATSParser::parseProgramAssociationTable(ABitReader *br) {
 
             if (!found) {
                 mPrograms.push(
-                        new Program(this, program_number, programMapPID));
+                        new Program(this, program_number, programMapPID, mLastRecoveredPTS));
             }
 
             if (mPSISections.indexOfKey(programMapPID) < 0) {
@@ -1098,10 +1183,12 @@ status_t ATSParser::parsePID(
 
         if (payload_unit_start_indicator) {
             if (!section->isEmpty()) {
-                return ERROR_UNSUPPORTED;
+                ALOGW("parsePID encounters payload_unit_start_indicator when section is not empty");
+                section->clear();
             }
 
             unsigned skip = br->getBits(8);
+            section->setSkipBytes(skip + 1);  // skip filler bytes + pointer field itself
             br->skipBits(skip * 8);
         }
 
@@ -1116,6 +1203,9 @@ status_t ATSParser::parsePID(
             return OK;
         }
 
+        if (!section->isCRCOkay()) {
+            return BAD_VALUE;
+        }
         ABitReader sectionBits(section->data(), section->size());
 
         if (PID == 0) {
@@ -1338,7 +1428,79 @@ void ATSParser::updatePCR(
 
 ////////////////////////////////////////////////////////////////////////////////
 
-ATSParser::PSISection::PSISection() {
+
+// CRC32 used for PSI section. The table was generated by following command:
+// $ python pycrc.py --model crc-32-mpeg --algorithm table-driven --generate c
+// Visit http://www.tty1.net/pycrc/index_en.html for more details.
+uint32_t ATSParser::PSISection::CRC_TABLE[] = {
+    0x00000000, 0x04c11db7, 0x09823b6e, 0x0d4326d9,
+    0x130476dc, 0x17c56b6b, 0x1a864db2, 0x1e475005,
+    0x2608edb8, 0x22c9f00f, 0x2f8ad6d6, 0x2b4bcb61,
+    0x350c9b64, 0x31cd86d3, 0x3c8ea00a, 0x384fbdbd,
+    0x4c11db70, 0x48d0c6c7, 0x4593e01e, 0x4152fda9,
+    0x5f15adac, 0x5bd4b01b, 0x569796c2, 0x52568b75,
+    0x6a1936c8, 0x6ed82b7f, 0x639b0da6, 0x675a1011,
+    0x791d4014, 0x7ddc5da3, 0x709f7b7a, 0x745e66cd,
+    0x9823b6e0, 0x9ce2ab57, 0x91a18d8e, 0x95609039,
+    0x8b27c03c, 0x8fe6dd8b, 0x82a5fb52, 0x8664e6e5,
+    0xbe2b5b58, 0xbaea46ef, 0xb7a96036, 0xb3687d81,
+    0xad2f2d84, 0xa9ee3033, 0xa4ad16ea, 0xa06c0b5d,
+    0xd4326d90, 0xd0f37027, 0xddb056fe, 0xd9714b49,
+    0xc7361b4c, 0xc3f706fb, 0xceb42022, 0xca753d95,
+    0xf23a8028, 0xf6fb9d9f, 0xfbb8bb46, 0xff79a6f1,
+    0xe13ef6f4, 0xe5ffeb43, 0xe8bccd9a, 0xec7dd02d,
+    0x34867077, 0x30476dc0, 0x3d044b19, 0x39c556ae,
+    0x278206ab, 0x23431b1c, 0x2e003dc5, 0x2ac12072,
+    0x128e9dcf, 0x164f8078, 0x1b0ca6a1, 0x1fcdbb16,
+    0x018aeb13, 0x054bf6a4, 0x0808d07d, 0x0cc9cdca,
+    0x7897ab07, 0x7c56b6b0, 0x71159069, 0x75d48dde,
+    0x6b93dddb, 0x6f52c06c, 0x6211e6b5, 0x66d0fb02,
+    0x5e9f46bf, 0x5a5e5b08, 0x571d7dd1, 0x53dc6066,
+    0x4d9b3063, 0x495a2dd4, 0x44190b0d, 0x40d816ba,
+    0xaca5c697, 0xa864db20, 0xa527fdf9, 0xa1e6e04e,
+    0xbfa1b04b, 0xbb60adfc, 0xb6238b25, 0xb2e29692,
+    0x8aad2b2f, 0x8e6c3698, 0x832f1041, 0x87ee0df6,
+    0x99a95df3, 0x9d684044, 0x902b669d, 0x94ea7b2a,
+    0xe0b41de7, 0xe4750050, 0xe9362689, 0xedf73b3e,
+    0xf3b06b3b, 0xf771768c, 0xfa325055, 0xfef34de2,
+    0xc6bcf05f, 0xc27dede8, 0xcf3ecb31, 0xcbffd686,
+    0xd5b88683, 0xd1799b34, 0xdc3abded, 0xd8fba05a,
+    0x690ce0ee, 0x6dcdfd59, 0x608edb80, 0x644fc637,
+    0x7a089632, 0x7ec98b85, 0x738aad5c, 0x774bb0eb,
+    0x4f040d56, 0x4bc510e1, 0x46863638, 0x42472b8f,
+    0x5c007b8a, 0x58c1663d, 0x558240e4, 0x51435d53,
+    0x251d3b9e, 0x21dc2629, 0x2c9f00f0, 0x285e1d47,
+    0x36194d42, 0x32d850f5, 0x3f9b762c, 0x3b5a6b9b,
+    0x0315d626, 0x07d4cb91, 0x0a97ed48, 0x0e56f0ff,
+    0x1011a0fa, 0x14d0bd4d, 0x19939b94, 0x1d528623,
+    0xf12f560e, 0xf5ee4bb9, 0xf8ad6d60, 0xfc6c70d7,
+    0xe22b20d2, 0xe6ea3d65, 0xeba91bbc, 0xef68060b,
+    0xd727bbb6, 0xd3e6a601, 0xdea580d8, 0xda649d6f,
+    0xc423cd6a, 0xc0e2d0dd, 0xcda1f604, 0xc960ebb3,
+    0xbd3e8d7e, 0xb9ff90c9, 0xb4bcb610, 0xb07daba7,
+    0xae3afba2, 0xaafbe615, 0xa7b8c0cc, 0xa379dd7b,
+    0x9b3660c6, 0x9ff77d71, 0x92b45ba8, 0x9675461f,
+    0x8832161a, 0x8cf30bad, 0x81b02d74, 0x857130c3,
+    0x5d8a9099, 0x594b8d2e, 0x5408abf7, 0x50c9b640,
+    0x4e8ee645, 0x4a4ffbf2, 0x470cdd2b, 0x43cdc09c,
+    0x7b827d21, 0x7f436096, 0x7200464f, 0x76c15bf8,
+    0x68860bfd, 0x6c47164a, 0x61043093, 0x65c52d24,
+    0x119b4be9, 0x155a565e, 0x18197087, 0x1cd86d30,
+    0x029f3d35, 0x065e2082, 0x0b1d065b, 0x0fdc1bec,
+    0x3793a651, 0x3352bbe6, 0x3e119d3f, 0x3ad08088,
+    0x2497d08d, 0x2056cd3a, 0x2d15ebe3, 0x29d4f654,
+    0xc5a92679, 0xc1683bce, 0xcc2b1d17, 0xc8ea00a0,
+    0xd6ad50a5, 0xd26c4d12, 0xdf2f6bcb, 0xdbee767c,
+    0xe3a1cbc1, 0xe760d676, 0xea23f0af, 0xeee2ed18,
+    0xf0a5bd1d, 0xf464a0aa, 0xf9278673, 0xfde69bc4,
+    0x89b8fd09, 0x8d79e0be, 0x803ac667, 0x84fbdbd0,
+    0x9abc8bd5, 0x9e7d9662, 0x933eb0bb, 0x97ffad0c,
+    0xafb010b1, 0xab710d06, 0xa6322bdf, 0xa2f33668,
+    0xbcb4666d, 0xb8757bda, 0xb5365d03, 0xb1f740b4
+    };
+
+ATSParser::PSISection::PSISection() :
+    mSkipBytes(0) {
 }
 
 ATSParser::PSISection::~PSISection() {
@@ -1369,10 +1531,15 @@ status_t ATSParser::PSISection::append(const void *data, size_t size) {
     return OK;
 }
 
+void ATSParser::PSISection::setSkipBytes(uint8_t skip) {
+    mSkipBytes = skip;
+}
+
 void ATSParser::PSISection::clear() {
     if (mBuffer != NULL) {
         mBuffer->setRange(0, 0);
     }
+    mSkipBytes = 0;
 }
 
 bool ATSParser::PSISection::isComplete() const {
@@ -1396,4 +1563,30 @@ size_t ATSParser::PSISection::size() const {
     return mBuffer == NULL ? 0 : mBuffer->size();
 }
 
+bool ATSParser::PSISection::isCRCOkay() const {
+    if (!isComplete()) {
+        return false;
+    }
+    uint8_t* data = mBuffer->data();
+
+    // Return true if section_syntax_indicator says no section follows the field section_length.
+    if ((data[1] & 0x80) == 0) {
+        return true;
+    }
+
+    unsigned sectionLength = U16_AT(data + 1) & 0xfff;
+    ALOGV("sectionLength %u, skip %u", sectionLength, mSkipBytes);
+
+    // Skip the preceding field present when payload start indicator is on.
+    sectionLength -= mSkipBytes;
+
+    uint32_t crc = 0xffffffff;
+    for(unsigned i = 0; i < sectionLength + 4 /* crc */; i++) {
+        uint8_t b = data[i];
+        int index = ((crc >> 24) ^ (b & 0xff)) & 0xff;
+        crc = CRC_TABLE[index] ^ (crc << 8);
+    }
+    ALOGV("crc: %08x\n", crc);
+    return (crc == 0);
+}
 }  // namespace android