diff -r 000000000000 -r 6474c204b198 content/media/ogg/OpusParser.cpp
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/content/media/ogg/OpusParser.cpp	Wed Dec 31 06:09:35 2014 +0100
@@ -0,0 +1,197 @@
+/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* vim:set ts=2 sw=2 sts=2 et cindent: */
+/* 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 <string.h>
+
+#include "mozilla/DebugOnly.h"
+#include "mozilla/Endian.h"
+#include <stdint.h>
+
+#include "OpusParser.h"
+
+#include "nsDebug.h"
+#include "MediaDecoderReader.h"
+#include "VideoUtils.h"
+#include <algorithm>
+
+#include "opus/opus.h"
+extern "C" {
+#include "opus/opus_multistream.h"
+}
+
+namespace mozilla {
+
+#ifdef PR_LOGGING
+extern PRLogModuleInfo* gMediaDecoderLog;
+#define OPUS_LOG(type, msg) PR_LOG(gMediaDecoderLog, type, msg)
+#else
+#define OPUS_LOG(type, msg)
+#endif
+
+OpusParser::OpusParser():
+  mRate(0),
+  mNominalRate(0),
+  mChannels(0),
+  mPreSkip(0),
+#ifdef MOZ_SAMPLE_TYPE_FLOAT32
+  mGain(1.0f),
+#else
+  mGain_Q16(65536),
+#endif
+  mChannelMapping(0),
+  mStreams(0),
+  mCoupledStreams(0)
+{ }
+
+bool OpusParser::DecodeHeader(unsigned char* aData, size_t aLength)
+{
+    if (aLength < 19 || memcmp(aData, "OpusHead", 8)) {
+      OPUS_LOG(PR_LOG_DEBUG, ("Invalid Opus file: unrecognized header"));
+      return false;
+    }
+
+    mRate = 48000; // The Opus decoder runs at 48 kHz regardless.
+
+    int version = aData[8];
+    // Accept file format versions 0.x.
+    if ((version & 0xf0) != 0) {
+      OPUS_LOG(PR_LOG_DEBUG, ("Rejecting unknown Opus file version %d", version));
+      return false;
+    }
+
+    mChannels = aData[9];
+    if (mChannels<1) {
+      OPUS_LOG(PR_LOG_DEBUG, ("Invalid Opus file: Number of channels %d", mChannels));
+      return false;
+    }
+
+    mPreSkip = LittleEndian::readUint16(aData + 10);
+    mNominalRate = LittleEndian::readUint32(aData + 12);
+    double gain_dB = LittleEndian::readInt16(aData + 16) / 256.0;
+#ifdef MOZ_SAMPLE_TYPE_FLOAT32
+    mGain = static_cast<float>(pow(10,0.05*gain_dB));
+#else
+    mGain_Q16 = static_cast<int32_t>(std::min(65536*pow(10,0.05*gain_dB)+0.5,
+                                            static_cast<double>(INT32_MAX)));
+#endif
+    mChannelMapping = aData[18];
+
+    if (mChannelMapping == 0) {
+      // Mapping family 0 only allows two channels
+      if (mChannels>2) {
+        OPUS_LOG(PR_LOG_DEBUG, ("Invalid Opus file: too many channels (%d) for"
+                           " mapping family 0.", mChannels));
+        return false;
+      }
+      mStreams = 1;
+      mCoupledStreams = mChannels - 1;
+      mMappingTable[0] = 0;
+      mMappingTable[1] = 1;
+    } else if (mChannelMapping == 1) {
+      // Currently only up to 8 channels are defined for mapping family 1
+      if (mChannels>8) {
+        OPUS_LOG(PR_LOG_DEBUG, ("Invalid Opus file: too many channels (%d) for"
+                           " mapping family 1.", mChannels));
+        return false;
+      }
+      if (aLength>static_cast<unsigned>(20+mChannels)) {
+        mStreams = aData[19];
+        mCoupledStreams = aData[20];
+        int i;
+        for (i=0; i<mChannels; i++)
+          mMappingTable[i] = aData[21+i];
+      } else {
+        OPUS_LOG(PR_LOG_DEBUG, ("Invalid Opus file: channel mapping %d,"
+                           " but no channel mapping table", mChannelMapping));
+        return false;
+      }
+    } else {
+      OPUS_LOG(PR_LOG_DEBUG, ("Invalid Opus file: unsupported channel mapping "
+                         "family %d", mChannelMapping));
+      return false;
+    }
+    if (mStreams < 1) {
+      OPUS_LOG(PR_LOG_DEBUG, ("Invalid Opus file: no streams"));
+      return false;
+    }
+    if (mCoupledStreams > mStreams) {
+      OPUS_LOG(PR_LOG_DEBUG, ("Invalid Opus file: more coupled streams (%d) than "
+                         "total streams (%d)", mCoupledStreams, mStreams));
+      return false;
+    }
+
+#ifdef DEBUG
+    OPUS_LOG(PR_LOG_DEBUG, ("Opus stream header:"));
+    OPUS_LOG(PR_LOG_DEBUG, (" channels: %d", mChannels));
+    OPUS_LOG(PR_LOG_DEBUG, ("  preskip: %d", mPreSkip));
+    OPUS_LOG(PR_LOG_DEBUG, (" original: %d Hz", mNominalRate));
+    OPUS_LOG(PR_LOG_DEBUG, ("     gain: %.2f dB", gain_dB));
+    OPUS_LOG(PR_LOG_DEBUG, ("Channel Mapping:"));
+    OPUS_LOG(PR_LOG_DEBUG, ("   family: %d", mChannelMapping));
+    OPUS_LOG(PR_LOG_DEBUG, ("  streams: %d", mStreams));
+#endif
+  return true;
+}
+
+bool OpusParser::DecodeTags(unsigned char* aData, size_t aLength)
+{
+  if (aLength < 16 || memcmp(aData, "OpusTags", 8))
+    return false;
+
+  // Copy out the raw comment lines, but only do basic validation
+  // checks against the string packing: too little data, too many
+  // comments, or comments that are too long. Rejecting these cases
+  // helps reduce the propagation of broken files.
+  // We do not ensure they are valid UTF-8 here, nor do we validate
+  // the required ASCII_TAG=value format of the user comments.
+  const unsigned char* buf = aData + 8;
+  uint32_t bytes = aLength - 8;
+  uint32_t len;
+  // Read the vendor string.
+  len = LittleEndian::readUint32(buf);
+  buf += 4;
+  bytes -= 4;
+  if (len > bytes)
+    return false;
+  mVendorString = nsCString(reinterpret_cast<const char*>(buf), len);
+  buf += len;
+  bytes -= len;
+  // Read the user comments.
+  if (bytes < 4)
+    return false;
+  uint32_t ncomments = LittleEndian::readUint32(buf);
+  buf += 4;
+  bytes -= 4;
+  // If there are so many comments even their length fields
+  // won't fit in the packet, stop reading now.
+  if (ncomments > (bytes>>2))
+    return false;
+  uint32_t i;
+  for (i = 0; i < ncomments; i++) {
+    if (bytes < 4)
+      return false;
+    len = LittleEndian::readUint32(buf);
+    buf += 4;
+    bytes -= 4;
+    if (len > bytes)
+      return false;
+    mTags.AppendElement(nsCString(reinterpret_cast<const char*>(buf), len));
+    buf += len;
+    bytes -= len;
+  }
+
+#ifdef DEBUG
+  OPUS_LOG(PR_LOG_DEBUG, ("Opus metadata header:"));
+  OPUS_LOG(PR_LOG_DEBUG, ("  vendor: %s", mVendorString.get()));
+  for (uint32_t i = 0; i < mTags.Length(); i++) {
+    OPUS_LOG(PR_LOG_DEBUG, (" %s", mTags[i].get()));
+  }
+#endif
+  return true;
+}
+
+} // namespace mozilla
+