diff options
Diffstat (limited to 'dom/media/ogg/OpusParser.cpp')
| -rw-r--r-- | dom/media/ogg/OpusParser.cpp | 185 |
1 files changed, 185 insertions, 0 deletions
diff --git a/dom/media/ogg/OpusParser.cpp b/dom/media/ogg/OpusParser.cpp new file mode 100644 index 000000000..7e62f6d5f --- /dev/null +++ b/dom/media/ogg/OpusParser.cpp @@ -0,0 +1,185 @@ +/* -*- 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 <algorithm> +#include "mozilla/EndianUtils.h" + +#include "OpusParser.h" +#include "VideoUtils.h" + +#include "opus/opus.h" +extern "C" { +#include "opus/opus_multistream.h" +} + +namespace mozilla { + +extern LazyLogModule gMediaDecoderLog; +#define OPUS_LOG(type, msg) MOZ_LOG(gMediaDecoderLog, type, msg) + +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(LogLevel::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(LogLevel::Debug, ("Rejecting unknown Opus file version %d", version)); + return false; + } + + mChannels = aData[9]; + if (mChannels<1) { + OPUS_LOG(LogLevel::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(LogLevel::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 || mChannelMapping == 255) { + // Currently only up to 8 channels are defined for mapping family 1 and we + // only supports only up to 8 channels for mapping family 255. + if (mChannels>8) { + OPUS_LOG(LogLevel::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(LogLevel::Debug, ("Invalid Opus file: channel mapping %d," + " but no channel mapping table", mChannelMapping)); + return false; + } + } else { + OPUS_LOG(LogLevel::Debug, ("Invalid Opus file: unsupported channel mapping " + "family %d", mChannelMapping)); + return false; + } + if (mStreams < 1) { + OPUS_LOG(LogLevel::Debug, ("Invalid Opus file: no streams")); + return false; + } + if (mCoupledStreams > mStreams) { + OPUS_LOG(LogLevel::Debug, ("Invalid Opus file: more coupled streams (%d) than " + "total streams (%d)", mCoupledStreams, mStreams)); + return false; + } + +#ifdef DEBUG + OPUS_LOG(LogLevel::Debug, ("Opus stream header:")); + OPUS_LOG(LogLevel::Debug, (" channels: %d", mChannels)); + OPUS_LOG(LogLevel::Debug, (" preskip: %d", mPreSkip)); + OPUS_LOG(LogLevel::Debug, (" original: %d Hz", mNominalRate)); + OPUS_LOG(LogLevel::Debug, (" gain: %.2f dB", gain_dB)); + OPUS_LOG(LogLevel::Debug, ("Channel Mapping:")); + OPUS_LOG(LogLevel::Debug, (" family: %d", mChannelMapping)); + OPUS_LOG(LogLevel::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; + for (uint32_t 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(LogLevel::Debug, ("Opus metadata header:")); + OPUS_LOG(LogLevel::Debug, (" vendor: %s", mVendorString.get())); + for (uint32_t i = 0; i < mTags.Length(); i++) { + OPUS_LOG(LogLevel::Debug, (" %s", mTags[i].get())); + } +#endif + return true; +} + +} // namespace mozilla |