Make sure timestamps attached to encoded media are composition timestamps.

not decoding timestamps. Obviously there is no difference between them if the
content in question does not involve frame reordering.

Change-Id: Iac4d06cfeb8a136f735c1148e98cac340d3ef893
related-to-bug: 3398314

1 files changed, 73 insertions, 0 deletions

diff --git a/media/libstagefright/SampleTable.cpp b/media/libstagefright/SampleTable.cpp
index a9163fc..423df70 100644
--- a/media/libstagefright/SampleTable.cpp
+++ b/media/libstagefright/SampleTable.cpp
@@ -53,6 +53,8 @@ SampleTable::SampleTable(const sp<DataSource> &source)
       mNumSampleSizes(0),
       mTimeToSampleCount(0),
       mTimeToSample(NULL),
+      mCompositionTimeDeltaEntries(NULL),
+      mNumCompositionTimeDeltaEntries(0),
       mSyncSampleOffset(-1),
       mNumSyncSamples(0),
       mSyncSamples(NULL),
@@ -68,6 +70,9 @@ SampleTable::~SampleTable() {
     delete[] mSyncSamples;
     mSyncSamples = NULL;
 
+    delete[] mCompositionTimeDeltaEntries;
+    mCompositionTimeDeltaEntries = NULL;
+
     delete[] mTimeToSample;
     mTimeToSample = NULL;
 
@@ -260,6 +265,51 @@ status_t SampleTable::setTimeToSampleParams(
     return OK;
 }
 
+status_t SampleTable::setCompositionTimeToSampleParams(
+        off64_t data_offset, size_t data_size) {
+    LOGI("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;
+    }
+
+    if (U32_AT(header) != 0) {
+        // Expected version = 0, flags = 0.
+        return ERROR_MALFORMED;
+    }
+
+    size_t numEntries = U32_AT(&header[4]);
+
+    if (data_size != (numEntries + 1) * 8) {
+        return ERROR_MALFORMED;
+    }
+
+    mNumCompositionTimeDeltaEntries = numEntries;
+    mCompositionTimeDeltaEntries = new uint32_t[2 * numEntries];
+
+    if (mDataSource->readAt(
+                data_offset + 8, mCompositionTimeDeltaEntries, numEntries * 8)
+            < (ssize_t)numEntries * 8) {
+        delete[] mCompositionTimeDeltaEntries;
+        mCompositionTimeDeltaEntries = NULL;
+
+        return ERROR_IO;
+    }
+
+    for (size_t i = 0; i < 2 * numEntries; ++i) {
+        mCompositionTimeDeltaEntries[i] = ntohl(mCompositionTimeDeltaEntries[i]);
+    }
+
+    return OK;
+}
+
 status_t SampleTable::setSyncSampleParams(off64_t data_offset, size_t data_size) {
     if (mSyncSampleOffset >= 0 || data_size < 8) {
         return ERROR_MALFORMED;
@@ -333,6 +383,8 @@ uint32_t abs_difference(uint32_t time1, uint32_t time2) {
 
 status_t SampleTable::findSampleAtTime(
         uint32_t req_time, uint32_t *sample_index, uint32_t flags) {
+    // XXX this currently uses decoding time, instead of composition time.
+
     *sample_index = 0;
 
     Mutex::Autolock autoLock(mLock);
@@ -607,5 +659,26 @@ status_t SampleTable::getMetaDataForSample(
     return OK;
 }
 
+uint32_t SampleTable::getCompositionTimeOffset(uint32_t sampleIndex) const {
+    if (mCompositionTimeDeltaEntries == NULL) {
+        return 0;
+    }
+
+    uint32_t curSample = 0;
+    for (size_t i = 0; i < mNumCompositionTimeDeltaEntries; ++i) {
+        uint32_t sampleCount = mCompositionTimeDeltaEntries[2 * i];
+
+        if (sampleIndex < curSample + sampleCount) {
+            uint32_t sampleDelta = mCompositionTimeDeltaEntries[2 * i + 1];
+
+            return sampleDelta;
+        }
+
+        curSample += sampleCount;
+    }
+
+    return 0;
+}
+
 }  // namespace android