Make extractors separate libraries

instead of being integrated into libstagefright

Test: thoroughly
Change-Id: I11cdfde6d2daf248c8e0f99237db1c74be260eb0
diff --git a/media/extractors/mp4/SampleTable.cpp b/media/extractors/mp4/SampleTable.cpp
new file mode 100644
index 0000000..d87d1b6
--- /dev/null
+++ b/media/extractors/mp4/SampleTable.cpp
@@ -0,0 +1,1000 @@
+/*
+ * Copyright (C) 2009 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_TAG "SampleTable"
+//#define LOG_NDEBUG 0
+#include <utils/Log.h>
+
+#include <limits>
+
+#include "SampleTable.h"
+#include "SampleIterator.h"
+
+#include <arpa/inet.h>
+
+#include <media/stagefright/foundation/ADebug.h>
+#include <media/stagefright/DataSource.h>
+#include <media/stagefright/Utils.h>
+
+/* TODO: remove after being merged into other branches */
+#ifndef UINT32_MAX
+#define UINT32_MAX       (4294967295U)
+#endif
+
+namespace android {
+
+// static
+const uint32_t SampleTable::kChunkOffsetType32 = FOURCC('s', 't', 'c', 'o');
+// static
+const uint32_t SampleTable::kChunkOffsetType64 = FOURCC('c', 'o', '6', '4');
+// static
+const uint32_t SampleTable::kSampleSizeType32 = FOURCC('s', 't', 's', 'z');
+// static
+const uint32_t SampleTable::kSampleSizeTypeCompact = FOURCC('s', 't', 'z', '2');
+
+////////////////////////////////////////////////////////////////////////////////
+
+const off64_t kMaxOffset = std::numeric_limits<off64_t>::max();
+
+struct SampleTable::CompositionDeltaLookup {
+    CompositionDeltaLookup();
+
+    void setEntries(
+            const int32_t *deltaEntries, size_t numDeltaEntries);
+
+    int32_t getCompositionTimeOffset(uint32_t sampleIndex);
+
+private:
+    Mutex mLock;
+
+    const int32_t *mDeltaEntries;
+    size_t mNumDeltaEntries;
+
+    size_t mCurrentDeltaEntry;
+    size_t mCurrentEntrySampleIndex;
+
+    DISALLOW_EVIL_CONSTRUCTORS(CompositionDeltaLookup);
+};
+
+SampleTable::CompositionDeltaLookup::CompositionDeltaLookup()
+    : mDeltaEntries(NULL),
+      mNumDeltaEntries(0),
+      mCurrentDeltaEntry(0),
+      mCurrentEntrySampleIndex(0) {
+}
+
+void SampleTable::CompositionDeltaLookup::setEntries(
+        const int32_t *deltaEntries, size_t numDeltaEntries) {
+    Mutex::Autolock autolock(mLock);
+
+    mDeltaEntries = deltaEntries;
+    mNumDeltaEntries = numDeltaEntries;
+    mCurrentDeltaEntry = 0;
+    mCurrentEntrySampleIndex = 0;
+}
+
+int32_t SampleTable::CompositionDeltaLookup::getCompositionTimeOffset(
+        uint32_t sampleIndex) {
+    Mutex::Autolock autolock(mLock);
+
+    if (mDeltaEntries == NULL) {
+        return 0;
+    }
+
+    if (sampleIndex < mCurrentEntrySampleIndex) {
+        mCurrentDeltaEntry = 0;
+        mCurrentEntrySampleIndex = 0;
+    }
+
+    while (mCurrentDeltaEntry < mNumDeltaEntries) {
+        uint32_t sampleCount = mDeltaEntries[2 * mCurrentDeltaEntry];
+        if (sampleIndex < mCurrentEntrySampleIndex + sampleCount) {
+            return mDeltaEntries[2 * mCurrentDeltaEntry + 1];
+        }
+
+        mCurrentEntrySampleIndex += sampleCount;
+        ++mCurrentDeltaEntry;
+    }
+
+    return 0;
+}
+
+////////////////////////////////////////////////////////////////////////////////
+
+SampleTable::SampleTable(const sp<DataSource> &source)
+    : mDataSource(source),
+      mChunkOffsetOffset(-1),
+      mChunkOffsetType(0),
+      mNumChunkOffsets(0),
+      mSampleToChunkOffset(-1),
+      mNumSampleToChunkOffsets(0),
+      mSampleSizeOffset(-1),
+      mSampleSizeFieldSize(0),
+      mDefaultSampleSize(0),
+      mNumSampleSizes(0),
+      mHasTimeToSample(false),
+      mTimeToSampleCount(0),
+      mTimeToSample(NULL),
+      mSampleTimeEntries(NULL),
+      mCompositionTimeDeltaEntries(NULL),
+      mNumCompositionTimeDeltaEntries(0),
+      mCompositionDeltaLookup(new CompositionDeltaLookup),
+      mSyncSampleOffset(-1),
+      mNumSyncSamples(0),
+      mSyncSamples(NULL),
+      mLastSyncSampleIndex(0),
+      mSampleToChunkEntries(NULL),
+      mTotalSize(0) {
+    mSampleIterator = new SampleIterator(this);
+}
+
+SampleTable::~SampleTable() {
+    delete[] mSampleToChunkEntries;
+    mSampleToChunkEntries = NULL;
+
+    delete[] mSyncSamples;
+    mSyncSamples = NULL;
+
+    delete[] mTimeToSample;
+    mTimeToSample = NULL;
+
+    delete mCompositionDeltaLookup;
+    mCompositionDeltaLookup = NULL;
+
+    delete[] mCompositionTimeDeltaEntries;
+    mCompositionTimeDeltaEntries = NULL;
+
+    delete[] mSampleTimeEntries;
+    mSampleTimeEntries = NULL;
+
+    delete mSampleIterator;
+    mSampleIterator = NULL;
+}
+
+bool SampleTable::isValid() const {
+    return mChunkOffsetOffset >= 0
+        && mSampleToChunkOffset >= 0
+        && mSampleSizeOffset >= 0
+        && mHasTimeToSample;
+}
+
+status_t SampleTable::setChunkOffsetParams(
+        uint32_t type, off64_t data_offset, size_t data_size) {
+    if (mChunkOffsetOffset >= 0) {
+        return ERROR_MALFORMED;
+    }
+
+    CHECK(type == kChunkOffsetType32 || type == kChunkOffsetType64);
+
+    mChunkOffsetOffset = data_offset;
+    mChunkOffsetType = type;
+
+    if (data_size < 8) {
+        return ERROR_MALFORMED;
+    }
+
+    uint8_t header[8];
+    if (mDataSource->readAt(
+                data_offset, header, sizeof(header)) < (ssize_t)sizeof(header)) {
+        return ERROR_IO;
+    }
+
+    if (U32_AT(header) != 0) {
+        // Expected version = 0, flags = 0.
+        return ERROR_MALFORMED;
+    }
+
+    mNumChunkOffsets = U32_AT(&header[4]);
+
+    if (mChunkOffsetType == kChunkOffsetType32) {
+      if ((data_size - 8) / 4 < mNumChunkOffsets) {
+            return ERROR_MALFORMED;
+        }
+    } else {
+      if ((data_size - 8) / 8 < mNumChunkOffsets) {
+            return ERROR_MALFORMED;
+        }
+    }
+
+    return OK;
+}
+
+status_t SampleTable::setSampleToChunkParams(
+        off64_t data_offset, size_t data_size) {
+    if (mSampleToChunkOffset >= 0) {
+        // already set
+        return ERROR_MALFORMED;
+    }
+
+    if (data_offset < 0) {
+        return ERROR_MALFORMED;
+    }
+
+    mSampleToChunkOffset = data_offset;
+
+    if (data_size < 8) {
+        return ERROR_MALFORMED;
+    }
+
+    uint8_t header[8];
+    if (mDataSource->readAt(
+                data_offset, header, sizeof(header)) < (ssize_t)sizeof(header)) {
+        return ERROR_IO;
+    }
+
+    if (U32_AT(header) != 0) {
+        // Expected version = 0, flags = 0.
+        return ERROR_MALFORMED;
+    }
+
+    mNumSampleToChunkOffsets = U32_AT(&header[4]);
+
+    if ((data_size - 8) / sizeof(SampleToChunkEntry) < mNumSampleToChunkOffsets) {
+        return ERROR_MALFORMED;
+    }
+
+    if ((uint64_t)kMaxTotalSize / sizeof(SampleToChunkEntry) <=
+            (uint64_t)mNumSampleToChunkOffsets) {
+        ALOGE("Sample-to-chunk table size too large.");
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mTotalSize += (uint64_t)mNumSampleToChunkOffsets *
+            sizeof(SampleToChunkEntry);
+    if (mTotalSize > kMaxTotalSize) {
+        ALOGE("Sample-to-chunk table size would make sample table too large.\n"
+              "    Requested sample-to-chunk table size = %llu\n"
+              "    Eventual sample table size >= %llu\n"
+              "    Allowed sample table size = %llu\n",
+              (unsigned long long)mNumSampleToChunkOffsets *
+                      sizeof(SampleToChunkEntry),
+              (unsigned long long)mTotalSize,
+              (unsigned long long)kMaxTotalSize);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mSampleToChunkEntries =
+        new (std::nothrow) SampleToChunkEntry[mNumSampleToChunkOffsets];
+    if (!mSampleToChunkEntries) {
+        ALOGE("Cannot allocate sample-to-chunk table with %llu entries.",
+                (unsigned long long)mNumSampleToChunkOffsets);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    if (mNumSampleToChunkOffsets == 0) {
+        return OK;
+    }
+
+    if ((off64_t)(kMaxOffset - 8 -
+            ((mNumSampleToChunkOffsets - 1) * sizeof(SampleToChunkEntry)))
+            < mSampleToChunkOffset) {
+        return ERROR_MALFORMED;
+    }
+
+    for (uint32_t i = 0; i < mNumSampleToChunkOffsets; ++i) {
+        uint8_t buffer[sizeof(SampleToChunkEntry)];
+
+        if (mDataSource->readAt(
+                    mSampleToChunkOffset + 8 + i * sizeof(SampleToChunkEntry),
+                    buffer,
+                    sizeof(buffer))
+                != (ssize_t)sizeof(buffer)) {
+            return ERROR_IO;
+        }
+        // chunk index is 1 based in the spec.
+        if (U32_AT(buffer) < 1) {
+            ALOGE("b/23534160");
+            return ERROR_OUT_OF_RANGE;
+        }
+
+        // We want the chunk index to be 0-based.
+        mSampleToChunkEntries[i].startChunk = U32_AT(buffer) - 1;
+        mSampleToChunkEntries[i].samplesPerChunk = U32_AT(&buffer[4]);
+        mSampleToChunkEntries[i].chunkDesc = U32_AT(&buffer[8]);
+    }
+
+    return OK;
+}
+
+status_t SampleTable::setSampleSizeParams(
+        uint32_t type, off64_t data_offset, size_t data_size) {
+    if (mSampleSizeOffset >= 0) {
+        return ERROR_MALFORMED;
+    }
+
+    CHECK(type == kSampleSizeType32 || type == kSampleSizeTypeCompact);
+
+    mSampleSizeOffset = data_offset;
+
+    if (data_size < 12) {
+        return ERROR_MALFORMED;
+    }
+
+    uint8_t header[12];
+    if (mDataSource->readAt(
+                data_offset, header, sizeof(header)) < (ssize_t)sizeof(header)) {
+        return ERROR_IO;
+    }
+
+    if (U32_AT(header) != 0) {
+        // Expected version = 0, flags = 0.
+        return ERROR_MALFORMED;
+    }
+
+    mDefaultSampleSize = U32_AT(&header[4]);
+    mNumSampleSizes = U32_AT(&header[8]);
+    if (mNumSampleSizes > (UINT32_MAX - 12) / 16) {
+        ALOGE("b/23247055, mNumSampleSizes(%u)", mNumSampleSizes);
+        return ERROR_MALFORMED;
+    }
+
+    if (type == kSampleSizeType32) {
+        mSampleSizeFieldSize = 32;
+
+        if (mDefaultSampleSize != 0) {
+            return OK;
+        }
+
+        if (data_size < 12 + mNumSampleSizes * 4) {
+            return ERROR_MALFORMED;
+        }
+    } else {
+        if ((mDefaultSampleSize & 0xffffff00) != 0) {
+            // The high 24 bits are reserved and must be 0.
+            return ERROR_MALFORMED;
+        }
+
+        mSampleSizeFieldSize = mDefaultSampleSize & 0xff;
+        mDefaultSampleSize = 0;
+
+        if (mSampleSizeFieldSize != 4 && mSampleSizeFieldSize != 8
+            && mSampleSizeFieldSize != 16) {
+            return ERROR_MALFORMED;
+        }
+
+        if (data_size < 12 + (mNumSampleSizes * mSampleSizeFieldSize + 4) / 8) {
+            return ERROR_MALFORMED;
+        }
+    }
+
+    return OK;
+}
+
+status_t SampleTable::setTimeToSampleParams(
+        off64_t data_offset, size_t data_size) {
+    if (mHasTimeToSample || data_size < 8) {
+        return ERROR_MALFORMED;
+    }
+
+    uint8_t header[8];
+    if (mDataSource->readAt(
+                data_offset, header, sizeof(header)) < (ssize_t)sizeof(header)) {
+        return ERROR_IO;
+    }
+
+    if (U32_AT(header) != 0) {
+        // Expected version = 0, flags = 0.
+        return ERROR_MALFORMED;
+    }
+
+    mTimeToSampleCount = U32_AT(&header[4]);
+    if (mTimeToSampleCount > UINT32_MAX / (2 * sizeof(uint32_t))) {
+        // Choose this bound because
+        // 1) 2 * sizeof(uint32_t) is the amount of memory needed for one
+        //    time-to-sample entry in the time-to-sample table.
+        // 2) mTimeToSampleCount is the number of entries of the time-to-sample
+        //    table.
+        // 3) We hope that the table size does not exceed UINT32_MAX.
+        ALOGE("Time-to-sample table size too large.");
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    // Note: At this point, we know that mTimeToSampleCount * 2 will not
+    // overflow because of the above condition.
+
+    uint64_t allocSize = (uint64_t)mTimeToSampleCount * 2 * sizeof(uint32_t);
+    mTotalSize += allocSize;
+    if (mTotalSize > kMaxTotalSize) {
+        ALOGE("Time-to-sample table size would make sample table too large.\n"
+              "    Requested time-to-sample table size = %llu\n"
+              "    Eventual sample table size >= %llu\n"
+              "    Allowed sample table size = %llu\n",
+              (unsigned long long)allocSize,
+              (unsigned long long)mTotalSize,
+              (unsigned long long)kMaxTotalSize);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mTimeToSample = new (std::nothrow) uint32_t[mTimeToSampleCount * 2];
+    if (!mTimeToSample) {
+        ALOGE("Cannot allocate time-to-sample table with %llu entries.",
+                (unsigned long long)mTimeToSampleCount);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    if (mDataSource->readAt(data_offset + 8, mTimeToSample,
+            (size_t)allocSize) < (ssize_t)allocSize) {
+        ALOGE("Incomplete data read for time-to-sample table.");
+        return ERROR_IO;
+    }
+
+    for (size_t i = 0; i < mTimeToSampleCount * 2; ++i) {
+        mTimeToSample[i] = ntohl(mTimeToSample[i]);
+    }
+
+    mHasTimeToSample = true;
+    return OK;
+}
+
+// NOTE: per 14996-12, version 0 ctts contains unsigned values, while version 1
+// contains signed values, however some software creates version 0 files that
+// contain signed values, so we're always treating the values as signed,
+// regardless of version.
+status_t SampleTable::setCompositionTimeToSampleParams(
+        off64_t data_offset, size_t data_size) {
+    ALOGI("There are reordered frames present.");
+
+    if (mCompositionTimeDeltaEntries != NULL || data_size < 8) {
+        return ERROR_MALFORMED;
+    }
+
+    uint8_t header[8];
+    if (mDataSource->readAt(
+                data_offset, header, sizeof(header))
+            < (ssize_t)sizeof(header)) {
+        return ERROR_IO;
+    }
+
+    uint32_t flags = U32_AT(header);
+    uint32_t version = flags >> 24;
+    flags &= 0xffffff;
+
+    if ((version != 0 && version != 1) || flags != 0) {
+        // Expected version = 0 or 1, flags = 0.
+        return ERROR_MALFORMED;
+    }
+
+    size_t numEntries = U32_AT(&header[4]);
+
+    if (((SIZE_MAX / 8) - 1 < numEntries) || (data_size != (numEntries + 1) * 8)) {
+        return ERROR_MALFORMED;
+    }
+
+    mNumCompositionTimeDeltaEntries = numEntries;
+    uint64_t allocSize = (uint64_t)numEntries * 2 * sizeof(int32_t);
+    if (allocSize > kMaxTotalSize) {
+        ALOGE("Composition-time-to-sample table size too large.");
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mTotalSize += allocSize;
+    if (mTotalSize > kMaxTotalSize) {
+        ALOGE("Composition-time-to-sample table would make sample table too large.\n"
+              "    Requested composition-time-to-sample table size = %llu\n"
+              "    Eventual sample table size >= %llu\n"
+              "    Allowed sample table size = %llu\n",
+              (unsigned long long)allocSize,
+              (unsigned long long)mTotalSize,
+              (unsigned long long)kMaxTotalSize);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mCompositionTimeDeltaEntries = new (std::nothrow) int32_t[2 * numEntries];
+    if (!mCompositionTimeDeltaEntries) {
+        ALOGE("Cannot allocate composition-time-to-sample table with %llu "
+                "entries.", (unsigned long long)numEntries);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    if (mDataSource->readAt(data_offset + 8, mCompositionTimeDeltaEntries,
+            (size_t)allocSize) < (ssize_t)allocSize) {
+        delete[] mCompositionTimeDeltaEntries;
+        mCompositionTimeDeltaEntries = NULL;
+
+        return ERROR_IO;
+    }
+
+    for (size_t i = 0; i < 2 * numEntries; ++i) {
+        mCompositionTimeDeltaEntries[i] = ntohl(mCompositionTimeDeltaEntries[i]);
+    }
+
+    mCompositionDeltaLookup->setEntries(
+            mCompositionTimeDeltaEntries, mNumCompositionTimeDeltaEntries);
+
+    return OK;
+}
+
+status_t SampleTable::setSyncSampleParams(off64_t data_offset, size_t data_size) {
+    if (mSyncSampleOffset >= 0 || data_size < 8) {
+        return ERROR_MALFORMED;
+    }
+
+    uint8_t header[8];
+    if (mDataSource->readAt(
+                data_offset, header, sizeof(header)) < (ssize_t)sizeof(header)) {
+        return ERROR_IO;
+    }
+
+    if (U32_AT(header) != 0) {
+        // Expected version = 0, flags = 0.
+        return ERROR_MALFORMED;
+    }
+
+    uint32_t numSyncSamples = U32_AT(&header[4]);
+
+    if (numSyncSamples < 2) {
+        ALOGV("Table of sync samples is empty or has only a single entry!");
+    }
+
+    uint64_t allocSize = (uint64_t)numSyncSamples * sizeof(uint32_t);
+    if (allocSize > kMaxTotalSize) {
+        ALOGE("Sync sample table size too large.");
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mTotalSize += allocSize;
+    if (mTotalSize > kMaxTotalSize) {
+        ALOGE("Sync sample table size would make sample table too large.\n"
+              "    Requested sync sample table size = %llu\n"
+              "    Eventual sample table size >= %llu\n"
+              "    Allowed sample table size = %llu\n",
+              (unsigned long long)allocSize,
+              (unsigned long long)mTotalSize,
+              (unsigned long long)kMaxTotalSize);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    mSyncSamples = new (std::nothrow) uint32_t[numSyncSamples];
+    if (!mSyncSamples) {
+        ALOGE("Cannot allocate sync sample table with %llu entries.",
+                (unsigned long long)numSyncSamples);
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    if (mDataSource->readAt(data_offset + 8, mSyncSamples,
+            (size_t)allocSize) != (ssize_t)allocSize) {
+        delete[] mSyncSamples;
+        mSyncSamples = NULL;
+        return ERROR_IO;
+    }
+
+    for (size_t i = 0; i < numSyncSamples; ++i) {
+        if (mSyncSamples[i] == 0) {
+            ALOGE("b/32423862, unexpected zero value in stss");
+            continue;
+        }
+        mSyncSamples[i] = ntohl(mSyncSamples[i]) - 1;
+    }
+
+    mSyncSampleOffset = data_offset;
+    mNumSyncSamples = numSyncSamples;
+
+    return OK;
+}
+
+uint32_t SampleTable::countChunkOffsets() const {
+    return mNumChunkOffsets;
+}
+
+uint32_t SampleTable::countSamples() const {
+    return mNumSampleSizes;
+}
+
+status_t SampleTable::getMaxSampleSize(size_t *max_size) {
+    Mutex::Autolock autoLock(mLock);
+
+    *max_size = 0;
+
+    for (uint32_t i = 0; i < mNumSampleSizes; ++i) {
+        size_t sample_size;
+        status_t err = getSampleSize_l(i, &sample_size);
+
+        if (err != OK) {
+            return err;
+        }
+
+        if (sample_size > *max_size) {
+            *max_size = sample_size;
+        }
+    }
+
+    return OK;
+}
+
+uint32_t abs_difference(uint32_t time1, uint32_t time2) {
+    return time1 > time2 ? time1 - time2 : time2 - time1;
+}
+
+// static
+int SampleTable::CompareIncreasingTime(const void *_a, const void *_b) {
+    const SampleTimeEntry *a = (const SampleTimeEntry *)_a;
+    const SampleTimeEntry *b = (const SampleTimeEntry *)_b;
+
+    if (a->mCompositionTime < b->mCompositionTime) {
+        return -1;
+    } else if (a->mCompositionTime > b->mCompositionTime) {
+        return 1;
+    }
+
+    return 0;
+}
+
+void SampleTable::buildSampleEntriesTable() {
+    Mutex::Autolock autoLock(mLock);
+
+    if (mSampleTimeEntries != NULL || mNumSampleSizes == 0) {
+        if (mNumSampleSizes == 0) {
+            ALOGE("b/23247055, mNumSampleSizes(%u)", mNumSampleSizes);
+        }
+        return;
+    }
+
+    mTotalSize += (uint64_t)mNumSampleSizes * sizeof(SampleTimeEntry);
+    if (mTotalSize > kMaxTotalSize) {
+        ALOGE("Sample entry table size would make sample table too large.\n"
+              "    Requested sample entry table size = %llu\n"
+              "    Eventual sample table size >= %llu\n"
+              "    Allowed sample table size = %llu\n",
+              (unsigned long long)mNumSampleSizes * sizeof(SampleTimeEntry),
+              (unsigned long long)mTotalSize,
+              (unsigned long long)kMaxTotalSize);
+        return;
+    }
+
+    mSampleTimeEntries = new (std::nothrow) SampleTimeEntry[mNumSampleSizes];
+    if (!mSampleTimeEntries) {
+        ALOGE("Cannot allocate sample entry table with %llu entries.",
+                (unsigned long long)mNumSampleSizes);
+        return;
+    }
+
+    uint32_t sampleIndex = 0;
+    uint32_t sampleTime = 0;
+
+    for (uint32_t i = 0; i < mTimeToSampleCount; ++i) {
+        uint32_t n = mTimeToSample[2 * i];
+        uint32_t delta = mTimeToSample[2 * i + 1];
+
+        for (uint32_t j = 0; j < n; ++j) {
+            if (sampleIndex < mNumSampleSizes) {
+                // Technically this should always be the case if the file
+                // is well-formed, but you know... there's (gasp) malformed
+                // content out there.
+
+                mSampleTimeEntries[sampleIndex].mSampleIndex = sampleIndex;
+
+                int32_t compTimeDelta =
+                    mCompositionDeltaLookup->getCompositionTimeOffset(
+                            sampleIndex);
+
+                if ((compTimeDelta < 0 && sampleTime <
+                        (compTimeDelta == INT32_MIN ?
+                                INT32_MAX : uint32_t(-compTimeDelta)))
+                        || (compTimeDelta > 0 &&
+                                sampleTime > UINT32_MAX - compTimeDelta)) {
+                    ALOGE("%u + %d would overflow, clamping",
+                            sampleTime, compTimeDelta);
+                    if (compTimeDelta < 0) {
+                        sampleTime = 0;
+                    } else {
+                        sampleTime = UINT32_MAX;
+                    }
+                    compTimeDelta = 0;
+                }
+
+                mSampleTimeEntries[sampleIndex].mCompositionTime =
+                        compTimeDelta > 0 ? sampleTime + compTimeDelta:
+                                sampleTime - (-compTimeDelta);
+            }
+
+            ++sampleIndex;
+            if (sampleTime > UINT32_MAX - delta) {
+                ALOGE("%u + %u would overflow, clamping",
+                    sampleTime, delta);
+                sampleTime = UINT32_MAX;
+            } else {
+                sampleTime += delta;
+            }
+        }
+    }
+
+    qsort(mSampleTimeEntries, mNumSampleSizes, sizeof(SampleTimeEntry),
+          CompareIncreasingTime);
+}
+
+status_t SampleTable::findSampleAtTime(
+        uint64_t req_time, uint64_t scale_num, uint64_t scale_den,
+        uint32_t *sample_index, uint32_t flags) {
+    buildSampleEntriesTable();
+
+    if (mSampleTimeEntries == NULL) {
+        return ERROR_OUT_OF_RANGE;
+    }
+
+    uint32_t left = 0;
+    uint32_t right_plus_one = mNumSampleSizes;
+    while (left < right_plus_one) {
+        uint32_t center = left + (right_plus_one - left) / 2;
+        uint64_t centerTime =
+            getSampleTime(center, scale_num, scale_den);
+
+        if (req_time < centerTime) {
+            right_plus_one = center;
+        } else if (req_time > centerTime) {
+            left = center + 1;
+        } else {
+            *sample_index = mSampleTimeEntries[center].mSampleIndex;
+            return OK;
+        }
+    }
+
+    uint32_t closestIndex = left;
+
+    if (closestIndex == mNumSampleSizes) {
+        if (flags == kFlagAfter) {
+            return ERROR_OUT_OF_RANGE;
+        }
+        flags = kFlagBefore;
+    } else if (closestIndex == 0) {
+        if (flags == kFlagBefore) {
+            // normally we should return out of range, but that is
+            // treated as end-of-stream.  instead return first sample
+            //
+            // return ERROR_OUT_OF_RANGE;
+        }
+        flags = kFlagAfter;
+    }
+
+    switch (flags) {
+        case kFlagBefore:
+        {
+            --closestIndex;
+            break;
+        }
+
+        case kFlagAfter:
+        {
+            // nothing to do
+            break;
+        }
+
+        default:
+        {
+            CHECK(flags == kFlagClosest);
+            // pick closest based on timestamp. use abs_difference for safety
+            if (abs_difference(
+                    getSampleTime(closestIndex, scale_num, scale_den), req_time) >
+                abs_difference(
+                    req_time, getSampleTime(closestIndex - 1, scale_num, scale_den))) {
+                --closestIndex;
+            }
+            break;
+        }
+    }
+
+    *sample_index = mSampleTimeEntries[closestIndex].mSampleIndex;
+    return OK;
+}
+
+status_t SampleTable::findSyncSampleNear(
+        uint32_t start_sample_index, uint32_t *sample_index, uint32_t flags) {
+    Mutex::Autolock autoLock(mLock);
+
+    *sample_index = 0;
+
+    if (mSyncSampleOffset < 0) {
+        // All samples are sync-samples.
+        *sample_index = start_sample_index;
+        return OK;
+    }
+
+    if (mNumSyncSamples == 0) {
+        *sample_index = 0;
+        return OK;
+    }
+
+    uint32_t left = 0;
+    uint32_t right_plus_one = mNumSyncSamples;
+    while (left < right_plus_one) {
+        uint32_t center = left + (right_plus_one - left) / 2;
+        uint32_t x = mSyncSamples[center];
+
+        if (start_sample_index < x) {
+            right_plus_one = center;
+        } else if (start_sample_index > x) {
+            left = center + 1;
+        } else {
+            *sample_index = x;
+            return OK;
+        }
+    }
+
+    if (left == mNumSyncSamples) {
+        if (flags == kFlagAfter) {
+            ALOGE("tried to find a sync frame after the last one: %d", left);
+            return ERROR_OUT_OF_RANGE;
+        }
+        flags = kFlagBefore;
+    }
+    else if (left == 0) {
+        if (flags == kFlagBefore) {
+            ALOGE("tried to find a sync frame before the first one: %d", left);
+
+            // normally we should return out of range, but that is
+            // treated as end-of-stream.  instead seek to first sync
+            //
+            // return ERROR_OUT_OF_RANGE;
+        }
+        flags = kFlagAfter;
+    }
+
+    // Now ssi[left - 1] <(=) start_sample_index <= ssi[left]
+    switch (flags) {
+        case kFlagBefore:
+        {
+            --left;
+            break;
+        }
+        case kFlagAfter:
+        {
+            // nothing to do
+            break;
+        }
+        default:
+        {
+            // this route is not used, but implement it nonetheless
+            CHECK(flags == kFlagClosest);
+
+            status_t err = mSampleIterator->seekTo(start_sample_index);
+            if (err != OK) {
+                return err;
+            }
+            uint32_t sample_time = mSampleIterator->getSampleTime();
+
+            err = mSampleIterator->seekTo(mSyncSamples[left]);
+            if (err != OK) {
+                return err;
+            }
+            uint32_t upper_time = mSampleIterator->getSampleTime();
+
+            err = mSampleIterator->seekTo(mSyncSamples[left - 1]);
+            if (err != OK) {
+                return err;
+            }
+            uint32_t lower_time = mSampleIterator->getSampleTime();
+
+            // use abs_difference for safety
+            if (abs_difference(upper_time, sample_time) >
+                abs_difference(sample_time, lower_time)) {
+                --left;
+            }
+            break;
+        }
+    }
+
+    *sample_index = mSyncSamples[left];
+    return OK;
+}
+
+status_t SampleTable::findThumbnailSample(uint32_t *sample_index) {
+    Mutex::Autolock autoLock(mLock);
+
+    if (mSyncSampleOffset < 0) {
+        // All samples are sync-samples.
+        *sample_index = 0;
+        return OK;
+    }
+
+    uint32_t bestSampleIndex = 0;
+    size_t maxSampleSize = 0;
+
+    static const size_t kMaxNumSyncSamplesToScan = 20;
+
+    // Consider the first kMaxNumSyncSamplesToScan sync samples and
+    // pick the one with the largest (compressed) size as the thumbnail.
+
+    size_t numSamplesToScan = mNumSyncSamples;
+    if (numSamplesToScan > kMaxNumSyncSamplesToScan) {
+        numSamplesToScan = kMaxNumSyncSamplesToScan;
+    }
+
+    for (size_t i = 0; i < numSamplesToScan; ++i) {
+        uint32_t x = mSyncSamples[i];
+
+        // Now x is a sample index.
+        size_t sampleSize;
+        status_t err = getSampleSize_l(x, &sampleSize);
+        if (err != OK) {
+            return err;
+        }
+
+        if (i == 0 || sampleSize > maxSampleSize) {
+            bestSampleIndex = x;
+            maxSampleSize = sampleSize;
+        }
+    }
+
+    *sample_index = bestSampleIndex;
+
+    return OK;
+}
+
+status_t SampleTable::getSampleSize_l(
+        uint32_t sampleIndex, size_t *sampleSize) {
+    return mSampleIterator->getSampleSizeDirect(
+            sampleIndex, sampleSize);
+}
+
+status_t SampleTable::getMetaDataForSample(
+        uint32_t sampleIndex,
+        off64_t *offset,
+        size_t *size,
+        uint32_t *compositionTime,
+        bool *isSyncSample,
+        uint32_t *sampleDuration) {
+    Mutex::Autolock autoLock(mLock);
+
+    status_t err;
+    if ((err = mSampleIterator->seekTo(sampleIndex)) != OK) {
+        return err;
+    }
+
+    if (offset) {
+        *offset = mSampleIterator->getSampleOffset();
+    }
+
+    if (size) {
+        *size = mSampleIterator->getSampleSize();
+    }
+
+    if (compositionTime) {
+        *compositionTime = mSampleIterator->getSampleTime();
+    }
+
+    if (isSyncSample) {
+        *isSyncSample = false;
+        if (mSyncSampleOffset < 0) {
+            // Every sample is a sync sample.
+            *isSyncSample = true;
+        } else {
+            size_t i = (mLastSyncSampleIndex < mNumSyncSamples)
+                    && (mSyncSamples[mLastSyncSampleIndex] <= sampleIndex)
+                ? mLastSyncSampleIndex : 0;
+
+            while (i < mNumSyncSamples && mSyncSamples[i] < sampleIndex) {
+                ++i;
+            }
+
+            if (i < mNumSyncSamples && mSyncSamples[i] == sampleIndex) {
+                *isSyncSample = true;
+            }
+
+            mLastSyncSampleIndex = i;
+        }
+    }
+
+    if (sampleDuration) {
+        *sampleDuration = mSampleIterator->getSampleDuration();
+    }
+
+    return OK;
+}
+
+int32_t SampleTable::getCompositionTimeOffset(uint32_t sampleIndex) {
+    return mCompositionDeltaLookup->getCompositionTimeOffset(sampleIndex);
+}
+
+}  // namespace android