Special mode for ESQueue that allows for earlier dequeuing of access units

if it's know beforehand that each PES packet contains exactly one access unit.
Currently this optimization is only supported for H.264 video.

Change-Id: I0888027cc7e9850307484b11dba1191cf6bfac83

2 files changed, 36 insertions, 4 deletions

diff --git a/media/libstagefright/mpeg2ts/ESQueue.cpp b/media/libstagefright/mpeg2ts/ESQueue.cpp
index 1cab077..e58e9bf 100644
--- a/media/libstagefright/mpeg2ts/ESQueue.cpp
+++ b/media/libstagefright/mpeg2ts/ESQueue.cpp
@@ -33,8 +33,9 @@
 
 namespace android {
 
-ElementaryStreamQueue::ElementaryStreamQueue(Mode mode)
-    : mMode(mode) {
+ElementaryStreamQueue::ElementaryStreamQueue(Mode mode, uint32_t flags)
+    : mMode(mode),
+      mFlags(flags) {
 }
 
 sp<MetaData> ElementaryStreamQueue::getFormat() {
@@ -289,6 +290,31 @@ status_t ElementaryStreamQueue::appendData(
 }
 
 sp<ABuffer> ElementaryStreamQueue::dequeueAccessUnit() {
+    if ((mFlags & kFlag_AlignedData) && mMode == H264) {
+        if (mRangeInfos.empty()) {
+            return NULL;
+        }
+
+        RangeInfo info = *mRangeInfos.begin();
+        mRangeInfos.erase(mRangeInfos.begin());
+
+        sp<ABuffer> accessUnit = new ABuffer(info.mLength);
+        memcpy(accessUnit->data(), mBuffer->data(), info.mLength);
+        accessUnit->meta()->setInt64("timeUs", info.mTimestampUs);
+
+        memmove(mBuffer->data(),
+                mBuffer->data() + info.mLength,
+                mBuffer->size() - info.mLength);
+
+        mBuffer->setRange(0, mBuffer->size() - info.mLength);
+
+        if (mFormat == NULL) {
+            mFormat = MakeAVCCodecSpecificData(accessUnit);
+        }
+
+        return accessUnit;
+    }
+
     switch (mMode) {
         case H264:
             return dequeueAccessUnitH264();
@@ -436,8 +462,8 @@ struct NALPosition {
 
 sp<ABuffer> ElementaryStreamQueue::dequeueAccessUnitH264() {
     const uint8_t *data = mBuffer->data();
-    size_t size = mBuffer->size();
 
+    size_t size = mBuffer->size();
     Vector<NALPosition> nals;
 
     size_t totalSize = 0;
diff --git a/media/libstagefright/mpeg2ts/ESQueue.h b/media/libstagefright/mpeg2ts/ESQueue.h
index 4035ed3..72aa2e7 100644
--- a/media/libstagefright/mpeg2ts/ESQueue.h
+++ b/media/libstagefright/mpeg2ts/ESQueue.h
@@ -36,7 +36,12 @@ struct ElementaryStreamQueue {
         MPEG_VIDEO,
         MPEG4_VIDEO,
     };
-    ElementaryStreamQueue(Mode mode);
+
+    enum Flags {
+        // Data appended to the queue is always at access unit boundaries.
+        kFlag_AlignedData = 1,
+    };
+    ElementaryStreamQueue(Mode mode, uint32_t flags = 0);
 
     status_t appendData(const void *data, size_t size, int64_t timeUs);
     void clear(bool clearFormat);
@@ -52,6 +57,7 @@ private:
     };
 
     Mode mMode;
+    uint32_t mFlags;
 
     sp<ABuffer> mBuffer;
     List<RangeInfo> mRangeInfos;