/* -*- 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