diff -r 000000000000 -r 6474c204b198 content/media/webm/EbmlComposer.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/media/webm/EbmlComposer.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,212 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*-*/
+/* This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "EbmlComposer.h"
+#include "libmkv/EbmlIDs.h"
+#include "libmkv/EbmlWriter.h"
+#include "libmkv/WebMElement.h"
+#include "prtime.h"
+
+namespace mozilla {
+
+// Timecode scale in nanoseconds
+static const unsigned long TIME_CODE_SCALE = 1000000;
+// The WebM header size without audio CodecPrivateData
+static const int32_t DEFAULT_HEADER_SIZE = 1024;
+
+void EbmlComposer::GenerateHeader()
+{
+  // Write the EBML header.
+  EbmlGlobal ebml;
+  // The WEbM header default size usually smaller than 1k.
+  nsAutoArrayPtr<uint8_t> buffer(new uint8_t[DEFAULT_HEADER_SIZE +
+                                             mCodecPrivateData.Length()]);
+  ebml.buf = buffer.get();
+  ebml.offset = 0;
+  writeHeader(&ebml);
+  {
+    EbmlLoc segEbmlLoc, ebmlLocseg, ebmlLoc;
+    Ebml_StartSubElement(&ebml, &segEbmlLoc, Segment);
+    {
+      Ebml_StartSubElement(&ebml, &ebmlLocseg, SeekHead);
+      // Todo: We don't know the exact sizes of encoded data and
+      // ignore this section.
+      Ebml_EndSubElement(&ebml, &ebmlLocseg);
+      writeSegmentInformation(&ebml, &ebmlLoc, TIME_CODE_SCALE, 0);
+      {
+        EbmlLoc trackLoc;
+        Ebml_StartSubElement(&ebml, &trackLoc, Tracks);
+        {
+          // Video
+          if (mWidth > 0 && mHeight > 0) {
+            writeVideoTrack(&ebml, 0x1, 0, "V_VP8",
+                            mWidth, mHeight,
+                            mDisplayWidth, mDisplayHeight, mFrameRate);
+          }
+          // Audio
+          if (mCodecPrivateData.Length() > 0) {
+            writeAudioTrack(&ebml, 0x2, 0x0, "A_VORBIS", mSampleFreq,
+                            mChannels, mCodecPrivateData.Elements(),
+                            mCodecPrivateData.Length());
+          }
+        }
+        Ebml_EndSubElement(&ebml, &trackLoc);
+      }
+    }
+    // The Recording length is unknown and
+    // ignore write the whole Segment element size
+  }
+  MOZ_ASSERT(ebml.offset <= DEFAULT_HEADER_SIZE + mCodecPrivateData.Length(),
+             "write more data > EBML_BUFFER_SIZE");
+  auto block = mClusterBuffs.AppendElement();
+  block->SetLength(ebml.offset);
+  memcpy(block->Elements(), ebml.buf, ebml.offset);
+  mFlushState |= FLUSH_METADATA;
+}
+
+void EbmlComposer::FinishMetadata()
+{
+  if (mFlushState & FLUSH_METADATA) {
+    // We don't remove the first element of mClusterBuffs because the
+    // |mClusterHeaderIndex| may have value.
+    mClusterCanFlushBuffs.AppendElement()->SwapElements(mClusterBuffs[0]);
+    mFlushState &= ~FLUSH_METADATA;
+  }
+}
+
+void EbmlComposer::FinishCluster()
+{
+  FinishMetadata();
+  if (!(mFlushState & FLUSH_CLUSTER)) {
+    // No completed cluster available.
+    return;
+  }
+
+  MOZ_ASSERT(mClusterLengthLoc > 0);
+  EbmlGlobal ebml;
+  EbmlLoc ebmlLoc;
+  ebmlLoc.offset = mClusterLengthLoc;
+  ebml.offset = mClusterBuffs[mClusterHeaderIndex].Length();
+  ebml.buf = mClusterBuffs[mClusterHeaderIndex].Elements();
+  Ebml_EndSubElement(&ebml, &ebmlLoc);
+  // Move the mClusterBuffs data from mClusterHeaderIndex that we can skip
+  // the metadata and the rest P-frames after ContainerWriter::FLUSH_NEEDED.
+  for (uint32_t i = mClusterHeaderIndex; i < mClusterBuffs.Length(); i++) {
+    mClusterCanFlushBuffs.AppendElement()->SwapElements(mClusterBuffs[i]);
+  }
+
+  mClusterHeaderIndex = 0;
+  mClusterLengthLoc = 0;
+  mClusterBuffs.Clear();
+  mFlushState &= ~FLUSH_CLUSTER;
+}
+
+void
+EbmlComposer::WriteSimpleBlock(EncodedFrame* aFrame)
+{
+  EbmlGlobal ebml;
+  ebml.offset = 0;
+
+  if (aFrame->GetFrameType() == EncodedFrame::FrameType::VP8_I_FRAME) {
+    FinishCluster();
+  }
+
+  auto block = mClusterBuffs.AppendElement();
+  block->SetLength(aFrame->GetFrameData().Length() + DEFAULT_HEADER_SIZE);
+  ebml.buf = block->Elements();
+
+  if (aFrame->GetFrameType() == EncodedFrame::FrameType::VP8_I_FRAME) {
+    EbmlLoc ebmlLoc;
+    Ebml_StartSubElement(&ebml, &ebmlLoc, Cluster);
+    MOZ_ASSERT(mClusterBuffs.Length() > 0);
+    // current cluster header array index
+    mClusterHeaderIndex = mClusterBuffs.Length() - 1;
+    mClusterLengthLoc = ebmlLoc.offset;
+    mClusterTimecode = aFrame->GetTimeStamp() / PR_USEC_PER_MSEC;
+    Ebml_SerializeUnsigned(&ebml, Timecode, mClusterTimecode);
+    mFlushState |= FLUSH_CLUSTER;
+  }
+
+  if (aFrame->GetFrameType() != EncodedFrame::FrameType::VORBIS_AUDIO_FRAME) {
+    short timeCode = aFrame->GetTimeStamp() / PR_USEC_PER_MSEC
+                     - mClusterTimecode;
+    writeSimpleBlock(&ebml, 0x1, timeCode, aFrame->GetFrameType() ==
+                     EncodedFrame::FrameType::VP8_I_FRAME,
+                     0, 0, (unsigned char*)aFrame->GetFrameData().Elements(),
+                     aFrame->GetFrameData().Length());
+  } else {
+    writeSimpleBlock(&ebml, 0x2, 0, false,
+                     0, 0, (unsigned char*)aFrame->GetFrameData().Elements(),
+                     aFrame->GetFrameData().Length());
+  }
+  MOZ_ASSERT(ebml.offset <= DEFAULT_HEADER_SIZE +
+             aFrame->GetFrameData().Length(),
+             "write more data > EBML_BUFFER_SIZE");
+  block->SetLength(ebml.offset);
+}
+
+void
+EbmlComposer::SetVideoConfig(uint32_t aWidth, uint32_t aHeight,
+                             uint32_t aDisplayWidth, uint32_t aDisplayHeight,
+                             float aFrameRate)
+{
+  MOZ_ASSERT(aWidth > 0, "Width should > 0");
+  MOZ_ASSERT(aHeight > 0, "Height should > 0");
+  MOZ_ASSERT(aDisplayWidth > 0, "DisplayWidth should > 0");
+  MOZ_ASSERT(aDisplayHeight > 0, "DisplayHeight should > 0");
+  MOZ_ASSERT(aFrameRate > 0, "FrameRate should > 0");
+  mWidth = aWidth;
+  mHeight = aHeight;
+  mDisplayWidth = aDisplayWidth;
+  mDisplayHeight = aDisplayHeight;
+  mFrameRate = aFrameRate;
+}
+
+void
+EbmlComposer::SetAudioConfig(uint32_t aSampleFreq, uint32_t aChannels,
+                             uint32_t aBitDepth)
+{
+  MOZ_ASSERT(aSampleFreq > 0, "SampleFreq should > 0");
+  MOZ_ASSERT(aBitDepth > 0, "BitDepth should > 0");
+  MOZ_ASSERT(aChannels > 0, "Channels should > 0");
+  mSampleFreq = aSampleFreq;
+  mBitDepth = aBitDepth;
+  mChannels = aChannels;
+}
+
+void
+EbmlComposer::ExtractBuffer(nsTArray<nsTArray<uint8_t> >* aDestBufs,
+                            uint32_t aFlag)
+{
+  if ((aFlag & ContainerWriter::FLUSH_NEEDED) ||
+      (aFlag & ContainerWriter::GET_HEADER))
+  {
+    FinishMetadata();
+  }
+  if (aFlag & ContainerWriter::FLUSH_NEEDED)
+  {
+    FinishCluster();
+  }
+  // aDestBufs may have some element
+  for (uint32_t i = 0; i < mClusterCanFlushBuffs.Length(); i++) {
+    aDestBufs->AppendElement()->SwapElements(mClusterCanFlushBuffs[i]);
+  }
+  mClusterCanFlushBuffs.Clear();
+}
+
+EbmlComposer::EbmlComposer()
+  : mFlushState(FLUSH_NONE)
+  , mClusterHeaderIndex(0)
+  , mClusterLengthLoc(0)
+  , mClusterTimecode(0)
+  , mWidth(0)
+  , mHeight(0)
+  , mFrameRate(0)
+  , mSampleFreq(0)
+  , mBitDepth(0)
+  , mChannels(0)
+{}
+
+}