/********** This library is free software; you can redistribute it and/or modify it under the terms of the GNU Lesser General Public License as published by the Free Software Foundation; either version 3 of the License, or (at your option) any later version. (See .) This library is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public License for more details. You should have received a copy of the GNU Lesser General Public License along with this library; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA **********/ // "liveMedia" // Copyright (c) 1996-2020 Live Networks, Inc. All rights reserved. // A parser for an Ogg file. // Implementation #include "OggFileParser.hh" #include "OggDemuxedTrack.hh" #include // for "gettimeofday() PacketSizeTable::PacketSizeTable(unsigned number_page_segments) : numCompletedPackets(0), totSizes(0), nextPacketNumToDeliver(0), lastPacketIsIncomplete(False) { size = new unsigned[number_page_segments]; for (unsigned i = 0; i < number_page_segments; ++i) size[i] = 0; } PacketSizeTable::~PacketSizeTable() { delete[] size; } OggFileParser::OggFileParser(OggFile& ourFile, FramedSource* inputSource, FramedSource::onCloseFunc* onEndFunc, void* onEndClientData, OggDemux* ourDemux) : StreamParser(inputSource, onEndFunc, onEndClientData, continueParsing, this), fOurFile(ourFile), fInputSource(inputSource), fOnEndFunc(onEndFunc), fOnEndClientData(onEndClientData), fOurDemux(ourDemux), fNumUnfulfilledTracks(0), fPacketSizeTable(NULL), fCurrentTrackNumber(0), fSavedPacket(NULL) { if (ourDemux == NULL) { // Initialization fCurrentParseState = PARSING_START_OF_FILE; continueParsing(); } else { fCurrentParseState = PARSING_AND_DELIVERING_PAGES; // In this case, parsing (of page data) doesn't start until a client starts reading from a track. } } OggFileParser::~OggFileParser() { delete[] fSavedPacket; delete fPacketSizeTable; Medium::close(fInputSource); } void OggFileParser::continueParsing(void* clientData, unsigned char* ptr, unsigned size, struct timeval presentationTime) { ((OggFileParser*)clientData)->continueParsing(); } void OggFileParser::continueParsing() { if (fInputSource != NULL) { if (fInputSource->isCurrentlyAwaitingData()) return; // Our input source is currently being read. Wait until that read completes if (!parse()) { // We didn't complete the parsing, because we had to read more data from the source, // or because we're waiting for another read from downstream. // Once that happens, we'll get called again. return; } } // We successfully parsed the file. Call our 'done' function now: if (fOnEndFunc != NULL) (*fOnEndFunc)(fOnEndClientData); } Boolean OggFileParser::parse() { try { while (1) { switch (fCurrentParseState) { case PARSING_START_OF_FILE: { if (parseStartOfFile()) return True; } case PARSING_AND_DELIVERING_PAGES: { parseAndDeliverPages(); } case DELIVERING_PACKET_WITHIN_PAGE: { if (deliverPacketWithinPage()) return False; } } } } catch (int /*e*/) { #ifdef DEBUG fprintf(stderr, "OggFileParser::parse() EXCEPTION (This is normal behavior - *not* an error)\n"); #endif return False; // the parsing got interrupted } } Boolean OggFileParser::parseStartOfFile() { #ifdef DEBUG fprintf(stderr, "parsing start of file\n"); #endif // Read and parse each 'page', until we see the first non-BOS page, or until we have // collected all required headers for Vorbis, Theora, or Opus track(s) (if any). u_int8_t header_type_flag; do { header_type_flag = parseInitialPage(); } while ((header_type_flag&0x02) != 0 || needHeaders()); #ifdef DEBUG fprintf(stderr, "Finished parsing start of file\n"); #endif return True; } static u_int32_t byteSwap(u_int32_t x) { return (x<<24)|((x<<8)&0x00FF0000)|((x>>8)&0x0000FF00)|(x>>24); } u_int8_t OggFileParser::parseInitialPage() { u_int8_t header_type_flag; u_int32_t bitstream_serial_number; parseStartOfPage(header_type_flag, bitstream_serial_number); // If this is a BOS page, examine the first 8 bytes of the first 'packet', to see whether // the track data type is one that we know how to stream: OggTrack* track; if ((header_type_flag&0x02) != 0) { // BOS char const* mimeType = NULL; // if unknown if (fPacketSizeTable != NULL && fPacketSizeTable->size[0] >= 8) { // sanity check char buf[8]; testBytes((u_int8_t*)buf, 8); if (strncmp(&buf[1], "vorbis", 6) == 0) { mimeType = "audio/VORBIS"; ++fNumUnfulfilledTracks; } else if (strncmp(buf, "OpusHead", 8) == 0) { mimeType = "audio/OPUS"; ++fNumUnfulfilledTracks; } else if (strncmp(&buf[1], "theora", 6) == 0) { mimeType = "video/THEORA"; ++fNumUnfulfilledTracks; } } // Add a new track descriptor for this track: track = new OggTrack; track->trackNumber = bitstream_serial_number; track->mimeType = mimeType; fOurFile.addTrack(track); } else { // not a BOS page // Because this is not a BOS page, the specified track should already have been seen: track = fOurFile.lookup(bitstream_serial_number); } if (track != NULL) { // sanity check #ifdef DEBUG fprintf(stderr, "This track's MIME type: %s\n", track->mimeType == NULL ? "(unknown)" : track->mimeType); #endif if (track->mimeType != NULL && (strcmp(track->mimeType, "audio/VORBIS") == 0 || strcmp(track->mimeType, "video/THEORA") == 0 || strcmp(track->mimeType, "audio/OPUS") == 0)) { // Special-case handling of Vorbis, Theora, or Opus tracks: // Make a copy of each packet, until we get the three special headers that we need: Boolean isVorbis = strcmp(track->mimeType, "audio/VORBIS") == 0; Boolean isTheora = strcmp(track->mimeType, "video/THEORA") == 0; for (unsigned j = 0; j < fPacketSizeTable->numCompletedPackets && track->weNeedHeaders(); ++j) { unsigned const packetSize = fPacketSizeTable->size[j]; if (packetSize == 0) continue; // sanity check delete[] fSavedPacket/*if any*/; fSavedPacket = new u_int8_t[packetSize]; getBytes(fSavedPacket, packetSize); fPacketSizeTable->totSizes -= packetSize; // The start of the packet tells us whether its a header that we know about: Boolean headerIsKnown = False; unsigned index = 0; if (isVorbis) { u_int8_t const firstByte = fSavedPacket[0]; headerIsKnown = firstByte == 1 || firstByte == 3 || firstByte == 5; index = (firstByte-1)/2; // 1, 3, or 5 => 0, 1, or 2 } else if (isTheora) { u_int8_t const firstByte = fSavedPacket[0]; headerIsKnown = firstByte == 0x80 || firstByte == 0x81 || firstByte == 0x82; index = firstByte &~0x80; // 0x80, 0x81, or 0x82 => 0, 1, or 2 } else { // Opus if (strncmp((char const*)fSavedPacket, "OpusHead", 8) == 0) { headerIsKnown = True; index = 0; // "identification" header } else if (strncmp((char const*)fSavedPacket, "OpusTags", 8) == 0) { headerIsKnown = True; index = 1; // "comment" header } } if (headerIsKnown) { #ifdef DEBUG char const* headerName[3] = { "identification", "comment", "setup" }; fprintf(stderr, "Saved %d-byte %s \"%s\" header\n", packetSize, track->mimeType, headerName[index]); #endif // This is a header, but first check it for validity: if (!validateHeader(track, fSavedPacket, packetSize)) continue; // Save this header (deleting any old header of the same type that we'd saved before) delete[] track->vtoHdrs.header[index]; track->vtoHdrs.header[index] = fSavedPacket; fSavedPacket = NULL; track->vtoHdrs.headerSize[index] = packetSize; if (!track->weNeedHeaders()) { // We now have all of the needed Vorbis, Theora, or Opus headers for this track: --fNumUnfulfilledTracks; } // Note: The above code won't work if a required header is fragmented over // more than one 'page'. We assume that that won't ever happen... } } } } // Skip over any remaining packet data bytes: if (fPacketSizeTable->totSizes > 0) { #ifdef DEBUG fprintf(stderr, "Skipping %d remaining packet data bytes\n", fPacketSizeTable->totSizes); #endif skipBytes(fPacketSizeTable->totSizes); } return header_type_flag; } // A simple bit vector class for reading bits in little-endian order. // (We can't use our usual "BitVector" class, because that's big-endian.) class LEBitVector { public: LEBitVector(u_int8_t const* p, unsigned numBytes) : fPtr(p), fEnd(&p[numBytes]), fNumBitsRemainingInCurrentByte(8) { } u_int32_t getBits(unsigned numBits/*<=32*/) { if (noMoreBits()) { return 0; } else if (numBits == fNumBitsRemainingInCurrentByte) { u_int32_t result = (*fPtr++)>>(8-fNumBitsRemainingInCurrentByte); fNumBitsRemainingInCurrentByte = 8; return result; } else if (numBits < fNumBitsRemainingInCurrentByte) { u_int8_t mask = 0xFF>>(8-numBits); u_int32_t result = ((*fPtr)>>(8-fNumBitsRemainingInCurrentByte)) & mask; fNumBitsRemainingInCurrentByte -= numBits; return result; } else { // numBits > fNumBitsRemainingInCurrentByte // Do two recursive calls to get the result: unsigned nbr = fNumBitsRemainingInCurrentByte; u_int32_t firstBits = getBits(nbr); u_int32_t nextBits = getBits(numBits - nbr); return (nextBits< 32) { (void)getBits(32); numBits -= 32; } (void)getBits(numBits); } unsigned numBitsRemaining() { return (fEnd-fPtr-1)*8 + fNumBitsRemainingInCurrentByte; } Boolean noMoreBits() const { return fPtr >= fEnd; } private: u_int8_t const* fPtr; u_int8_t const* fEnd; unsigned fNumBitsRemainingInCurrentByte; // 1..8 }; static unsigned ilog(int n) { if (n < 0) return 0; unsigned x = (unsigned)n; unsigned result = 0; while (x > 0) { ++result; x >>= 1; } return result; } static unsigned lookup1_values(unsigned codebook_entries, unsigned codebook_dimensions) { // "the greatest integer value for which [return_value] to the power of [codebook_dimensions] // is less than or equal to [codebook_entries]" unsigned return_value = 0; unsigned powerValue; do { ++return_value; // Compute powerValue = return_value ** codebook_dimensions if (return_value == 1) powerValue = 1; // optimization else { powerValue = 1; for (unsigned i = 0; i < codebook_dimensions; ++i) { powerValue *= return_value; } } } while (powerValue <= codebook_entries); return_value -= 1; return return_value; } static Boolean parseVorbisSetup_codebook(LEBitVector& bv) { if (bv.noMoreBits()) return False; unsigned sync = bv.getBits(24); if (sync != 0x564342) return False; unsigned codebook_dimensions = bv.getBits(16); unsigned codebook_entries = bv.getBits(24); unsigned ordered = bv.getBits(1); #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\t\t\tcodebook_dimensions: %d; codebook_entries: %d, ordered: %d\n", codebook_dimensions, codebook_entries, ordered); #endif if (!ordered) { unsigned sparse = bv.getBits(1); #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\t\t\t!ordered: sparse %d\n", sparse); #endif for (unsigned i = 0; i < codebook_entries; ++i) { unsigned codewordLength; if (sparse) { unsigned flag = bv.getBits(1); if (flag) { codewordLength = bv.getBits(5) + 1; } else { codewordLength = 0; } } else { codewordLength = bv.getBits(5) + 1; } #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\t\t\t\tcodeword length[%d]:\t%d\n", i, codewordLength); #else codewordLength = codewordLength; // to prevent compiler warning #endif } } else { // ordered #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\t\t\tordered:\n"); #endif unsigned current_entry = 0; unsigned current_length = bv.getBits(5) + 1; do { unsigned number = bv.getBits(ilog(codebook_entries - current_entry)); #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\t\t\t\tcodeword length[%d..%d]:\t%d\n", current_entry, current_entry + number - 1, current_length); #endif current_entry += number; if (current_entry > codebook_entries) { fprintf(stderr, "Vorbis codebook parsing error: current_entry %d > codebook_entries %d!\n", current_entry, codebook_entries); return False; } ++current_length; } while (current_entry < codebook_entries); } unsigned codebook_lookup_type = bv.getBits(4); #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\t\t\tcodebook_lookup_type: %d\n", codebook_lookup_type); #endif if (codebook_lookup_type > 2) { fprintf(stderr, "Vorbis codebook parsing error: codebook_lookup_type %d!\n", codebook_lookup_type); return False; } else if (codebook_lookup_type > 0) { // 1 or 2 bv.skipBits(32+32); // "codebook_minimum_value" and "codebook_delta_value" unsigned codebook_value_bits = bv.getBits(4) + 1; bv.skipBits(1); // "codebook_lookup_p" unsigned codebook_lookup_values; if (codebook_lookup_type == 1) { codebook_lookup_values = lookup1_values(codebook_entries, codebook_dimensions); } else { // 2 codebook_lookup_values = codebook_entries*codebook_dimensions; } bv.skipBits(codebook_lookup_values*codebook_value_bits); // "codebook_multiplicands" } return True; } static Boolean parseVorbisSetup_codebooks(LEBitVector& bv) { if (bv.noMoreBits()) return False; unsigned vorbis_codebook_count = bv.getBits(8) + 1; #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\tCodebooks: vorbis_codebook_count: %d\n", vorbis_codebook_count); #endif for (unsigned i = 0; i < vorbis_codebook_count; ++i) { #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\t\tCodebook %d:\n", i); #endif if (!parseVorbisSetup_codebook(bv)) return False; } return True; } static Boolean parseVorbisSetup_timeDomainTransforms(LEBitVector& bv) { if (bv.noMoreBits()) return False; unsigned vorbis_time_count = bv.getBits(6) + 1; #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\tTime domain transforms: vorbis_time_count: %d\n", vorbis_time_count); #endif for (unsigned i = 0; i < vorbis_time_count; ++i) { unsigned val = bv.getBits(16); if (val != 0) { fprintf(stderr, "Vorbis Time domain transforms, read non-zero value %d\n", val); return False; } } return True; } static Boolean parseVorbisSetup_floors(LEBitVector& bv) { if (bv.noMoreBits()) return False; unsigned vorbis_floor_count = bv.getBits(6) + 1; #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\tFloors: vorbis_floor_count: %d\n", vorbis_floor_count); #endif for (unsigned i = 0; i < vorbis_floor_count; ++i) { unsigned floorType = bv.getBits(16); if (floorType == 0) { bv.skipBits(8+16+16+6+8); unsigned floor0_number_of_books = bv.getBits(4) + 1; bv.skipBits(floor0_number_of_books*8); } else if (floorType == 1) { unsigned floor1_partitions = bv.getBits(5); unsigned* floor1_partition_class_list = new unsigned[floor1_partitions]; unsigned maximum_class = 0, j; for (j = 0; j < floor1_partitions; ++j) { floor1_partition_class_list[j] = bv.getBits(4); if (floor1_partition_class_list[j] > maximum_class) maximum_class = floor1_partition_class_list[j]; } unsigned* floor1_class_dimensions = new unsigned[maximum_class + 1]; for (j = 0; j <= maximum_class; ++j) { floor1_class_dimensions[j] = bv.getBits(3) + 1; unsigned floor1_class_subclasses = bv.getBits(2); if (floor1_class_subclasses != 0) { bv.skipBits(8); // "floor1_class_masterbooks[j]" } unsigned twoExp_floor1_class_subclasses = 1 << floor1_class_subclasses; bv.skipBits(twoExp_floor1_class_subclasses*8); // "floor1_subclass_books[j][*]" } bv.skipBits(2); // "floor1_multiplier" unsigned rangebits = bv.getBits(4); for (j = 0; j < floor1_partitions; ++j) { unsigned current_class_number = floor1_partition_class_list[j]; bv.skipBits(floor1_class_dimensions[current_class_number] * rangebits); } delete[] floor1_partition_class_list; delete[] floor1_class_dimensions; } else { // floorType > 1 fprintf(stderr, "Vorbis Floors, read bad floor type %d\n", floorType); return False; } } return True; } static Boolean parseVorbisSetup_residues(LEBitVector& bv) { if (bv.noMoreBits()) return False; unsigned vorbis_residue_count = bv.getBits(6) + 1; #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\tResidues: vorbis_residue_count: %d\n", vorbis_residue_count); #endif for (unsigned i = 0; i < vorbis_residue_count; ++i) { unsigned vorbis_residue_type = bv.getBits(16); if (vorbis_residue_type > 2) { fprintf(stderr, "Vorbis Residues, read bad vorbis_residue_type: %d\n", vorbis_residue_type); return False; } else { bv.skipBits(24+24+24); // "residue_begin", "residue_end", "residue_partition_size" unsigned residue_classifications = bv.getBits(6) + 1; bv.skipBits(8); // "residue_classbook" u_int8_t* residue_cascade = new u_int8_t[residue_classifications]; unsigned j; for (j = 0; j < residue_classifications; ++j) { u_int8_t high_bits = 0; u_int8_t low_bits = bv.getBits(3); unsigned bitflag = bv.getBits(1); if (bitflag) { high_bits = bv.getBits(5); } residue_cascade[j] = (high_bits<<3) | low_bits; } for (j = 0; j < residue_classifications; ++j) { u_int8_t const cascade = residue_cascade[j]; u_int8_t mask = 0x80; while (mask != 0) { if ((cascade&mask) != 0) bv.skipBits(8); // "residue_books[j][*]" mask >>= 1; } } delete[] residue_cascade; } } return True; } static Boolean parseVorbisSetup_mappings(LEBitVector& bv, unsigned audio_channels) { if (bv.noMoreBits()) return False; unsigned vorbis_mapping_count = bv.getBits(6) + 1; #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\tMappings: vorbis_mapping_count: %d\n", vorbis_mapping_count); #endif for (unsigned i = 0; i < vorbis_mapping_count; ++i) { unsigned vorbis_mapping_type = bv.getBits(16); if (vorbis_mapping_type != 0) { fprintf(stderr, "Vorbis Mappings, read bad vorbis_mapping_type: %d\n", vorbis_mapping_type); return False; } unsigned vorbis_mapping_submaps = 1; if (bv.getBits(1)) vorbis_mapping_submaps = bv.getBits(4) + 1; if (bv.getBits(1)) { // "square polar channel mapping is in use" unsigned vorbis_mapping_coupling_steps = bv.getBits(8) + 1; for (unsigned j = 0; j < vorbis_mapping_coupling_steps; ++j) { unsigned ilog_audio_channels_minus_1 = ilog(audio_channels - 1); bv.skipBits(2*ilog_audio_channels_minus_1); // "vorbis_mapping_magnitude", "vorbis_mapping_angle" } } unsigned reserved = bv.getBits(2); if (reserved != 0) { fprintf(stderr, "Vorbis Mappings, read bad 'reserved' field\n"); return False; } if (vorbis_mapping_submaps > 1) { for (unsigned j = 0; j < audio_channels; ++j) { unsigned vorbis_mapping_mux = bv.getBits(4); fprintf(stderr, "\t\t\t\tvorbis_mapping_mux[%d]: %d\n", j, vorbis_mapping_mux); if (vorbis_mapping_mux >= vorbis_mapping_submaps) { fprintf(stderr, "Vorbis Mappings, read bad \"vorbis_mapping_mux\" %d (>= \"vorbis_mapping_submaps\" %d)\n", vorbis_mapping_mux, vorbis_mapping_submaps); return False; } } } bv.skipBits(vorbis_mapping_submaps*(8+8+8)); // "the floor and residue numbers" } return True; } static Boolean parseVorbisSetup_modes(LEBitVector& bv, OggTrack* track) { if (bv.noMoreBits()) return False; unsigned vorbis_mode_count = bv.getBits(6) + 1; unsigned ilog_vorbis_mode_count_minus_1 = ilog(vorbis_mode_count - 1); #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\tModes: vorbis_mode_count: %d (ilog(%d-1):%d)\n", vorbis_mode_count, vorbis_mode_count, ilog_vorbis_mode_count_minus_1); #endif track->vtoHdrs.vorbis_mode_count = vorbis_mode_count; track->vtoHdrs.ilog_vorbis_mode_count_minus_1 = ilog_vorbis_mode_count_minus_1; track->vtoHdrs.vorbis_mode_blockflag = new u_int8_t[vorbis_mode_count]; for (unsigned i = 0; i < vorbis_mode_count; ++i) { track->vtoHdrs.vorbis_mode_blockflag[i] = (u_int8_t)bv.getBits(1); #ifdef DEBUG_SETUP_HEADER fprintf(stderr, "\t\tMode %d: vorbis_mode_blockflag: %d\n", i, track->vtoHdrs.vorbis_mode_blockflag[i]); #endif bv.skipBits(16+16+8); // "vorbis_mode_windowtype", "vorbis_mode_transformtype", "vorbis_mode_mapping" } return True; } static Boolean parseVorbisSetupHeader(OggTrack* track, u_int8_t const* p, unsigned headerSize) { LEBitVector bv(p, headerSize); do { if (!parseVorbisSetup_codebooks(bv)) break; if (!parseVorbisSetup_timeDomainTransforms(bv)) break; if (!parseVorbisSetup_floors(bv)) break; if (!parseVorbisSetup_residues(bv)) break; if (!parseVorbisSetup_mappings(bv, track->numChannels)) break; if (!parseVorbisSetup_modes(bv, track)) break; unsigned framingFlag = bv.getBits(1); if (framingFlag == 0) { fprintf(stderr, "Vorbis \"setup\" header did not end with a 'framing flag'!\n"); break; } return True; } while (0); // An error occurred: return False; } #ifdef DEBUG #define CHECK_PTR if (p >= pEnd) return False #define printComment(p, len) do { for (unsigned k = 0; k < len; ++k) { CHECK_PTR; fprintf(stderr, "%c", *p++); } } while (0) #endif static Boolean validateCommentHeader(u_int8_t const *p, unsigned headerSize, unsigned isOpus = 0) { if (headerSize < 15+isOpus) { // need 7+isOpus + 4(vendor_length) + 4(user_comment_list_length) fprintf(stderr, "\"comment\" header is too short (%d bytes)\n", headerSize); return False; } #ifdef DEBUG u_int8_t const* pEnd = &p[headerSize]; p += 7+isOpus; u_int32_t vendor_length = (p[3]<<24)|(p[2]<<16)|(p[1]<<8)|p[0]; p += 4; fprintf(stderr, "\tvendor_string:"); printComment(p, vendor_length); fprintf(stderr, "\n"); u_int32_t user_comment_list_length = (p[3]<<24)|(p[2]<<16)|(p[1]<<8)|p[0]; p += 4; for (unsigned i = 0; i < user_comment_list_length; ++i) { CHECK_PTR; u_int32_t length = (p[3]<<24)|(p[2]<<16)|(p[1]<<8)|p[0]; p += 4; fprintf(stderr, "\tuser_comment[%d]:", i); printComment(p, length); fprintf(stderr, "\n"); } #endif return True; } static unsigned blocksizeFromExponent(unsigned exponent) { unsigned result = 1; for (unsigned i = 0; i < exponent; ++i) result = 2*result; return result; } Boolean OggFileParser::validateHeader(OggTrack* track, u_int8_t const* p, unsigned headerSize) { // Assert: headerSize >= 7 (because we've already checked "XXXXXX" or "OpusXXXX") if (strcmp(track->mimeType, "audio/VORBIS") == 0) { u_int8_t const firstByte = p[0]; if (firstByte == 1) { // "identification" header if (headerSize < 30) { fprintf(stderr, "Vorbis \"identification\" header is too short (%d bytes)\n", headerSize); return False; } else if ((p[29]&0x1) != 1) { fprintf(stderr, "Vorbis \"identification\" header: 'framing_flag' is not set\n"); return False; } p += 7; u_int32_t vorbis_version = (p[3]<<24)|(p[2]<<16)|(p[1]<<8)|p[0]; p += 4; if (vorbis_version != 0) { fprintf(stderr, "Vorbis \"identification\" header has a bad 'vorbis_version': 0x%08x\n", vorbis_version); return False; } u_int8_t audio_channels = *p++; if (audio_channels == 0) { fprintf(stderr, "Vorbis \"identification\" header: 'audio_channels' is 0!\n"); return False; } track->numChannels = audio_channels; u_int32_t audio_sample_rate = (p[3]<<24)|(p[2]<<16)|(p[1]<<8)|p[0]; p += 4; if (audio_sample_rate == 0) { fprintf(stderr, "Vorbis \"identification\" header: 'audio_sample_rate' is 0!\n"); return False; } track->samplingFrequency = audio_sample_rate; p += 4; // skip over 'bitrate_maximum' u_int32_t bitrate_nominal = (p[3]<<24)|(p[2]<<16)|(p[1]<<8)|p[0]; p += 4; if (bitrate_nominal > 0) track->estBitrate = (bitrate_nominal+500)/1000; // round p += 4; // skip over 'bitrate_maximum' // Note the two 'block sizes' (samples per packet), and their durations in microseconds: u_int8_t blocksizeBits = *p++; unsigned& blocksize_0 = track->vtoHdrs.blocksize[0]; // alias unsigned& blocksize_1 = track->vtoHdrs.blocksize[1]; // alias blocksize_0 = blocksizeFromExponent(blocksizeBits&0x0F); blocksize_1 = blocksizeFromExponent(blocksizeBits>>4); double uSecsPerSample = 1000000.0/(track->samplingFrequency*2); // Why the "2"? I don't know, but it seems to be necessary track->vtoHdrs.uSecsPerPacket[0] = (unsigned)(uSecsPerSample*blocksize_0); track->vtoHdrs.uSecsPerPacket[1] = (unsigned)(uSecsPerSample*blocksize_1); #ifdef DEBUG fprintf(stderr, "\t%u Hz, %u-channel, %u kbps (est), block sizes: %u,%u (%u,%u us)\n", track->samplingFrequency, track->numChannels, track->estBitrate, blocksize_0, blocksize_1, track->vtoHdrs.uSecsPerPacket[0], track->vtoHdrs.uSecsPerPacket[1]); #endif // To be valid, "blocksize_0" must be <= "blocksize_1", and both must be in [64,8192]: if (!(blocksize_0 <= blocksize_1 && blocksize_0 >= 64 && blocksize_1 <= 8192)) { fprintf(stderr, "Invalid Vorbis \"blocksize_0\" (%d) and/or \"blocksize_1\" (%d)!\n", blocksize_0, blocksize_1); return False; } } else if (firstByte == 3) { // "comment" header if (!validateCommentHeader(p, headerSize)) return False; } else if (firstByte == 5) { // "setup" header // Parse the "setup" header to get the values that we want: // "vorbis_mode_count", and "vorbis_mode_blockflag" for each mode. Unfortunately these come // near the end of the header, so we have to parse lots of other crap first. p += 7; if (!parseVorbisSetupHeader(track, p, headerSize)) { fprintf(stderr, "Failed to parse Vorbis \"setup\" header!\n"); return False; } } } else if (strcmp(track->mimeType, "video/THEORA") == 0) { u_int8_t const firstByte = p[0]; if (firstByte == 0x80) { // "identification" header if (headerSize < 42) { fprintf(stderr, "Theora \"identification\" header is too short (%d bytes)\n", headerSize); return False; } else if ((p[41]&0x7) != 0) { fprintf(stderr, "Theora \"identification\" header: 'res' bits are non-zero\n"); return False; } track->vtoHdrs.KFGSHIFT = ((p[40]&3)<<3) | (p[41]>>5); u_int32_t FRN = (p[22]<<24) | (p[23]<<16) | (p[24]<<8) | p[25]; // Frame rate numerator u_int32_t FRD = (p[26]<<24) | (p[27]<<16) | (p[28]<<8) | p[29]; // Frame rate numerator #ifdef DEBUG fprintf(stderr, "\tKFGSHIFT %d, Frame rate numerator %d, Frame rate denominator %d\n", track->vtoHdrs.KFGSHIFT, FRN, FRD); #endif if (FRN == 0 || FRD == 0) { fprintf(stderr, "Theora \"identification\" header: Bad FRN and/or FRD values: %d, %d\n", FRN, FRD); return False; } track->vtoHdrs.uSecsPerFrame = (unsigned)((1000000.0*FRD)/FRN); #ifdef DEBUG fprintf(stderr, "\t\t=> %u microseconds per frame\n", track->vtoHdrs.uSecsPerFrame); #endif } else if (firstByte == 0x81) { // "comment" header if (!validateCommentHeader(p, headerSize)) return False; } else if (firstByte == 0x82) { // "setup" header // We don't care about the contents of the Theora "setup" header; just assume it's valid } } else { // Opus audio if (strncmp((char const*)p, "OpusHead", 8) == 0) { // "identification" header // Just check the size, and the 'major' number of the version byte: if (headerSize < 19 || (p[8]&0xF0) != 0) return False; } else { // comment header if (!validateCommentHeader(p, headerSize, 1/*isOpus*/)) return False; } } return True; } void OggFileParser::parseAndDeliverPages() { #ifdef DEBUG fprintf(stderr, "parsing and delivering data\n"); #endif while (parseAndDeliverPage()) {} } Boolean OggFileParser::parseAndDeliverPage() { u_int8_t header_type_flag; u_int32_t bitstream_serial_number; parseStartOfPage(header_type_flag, bitstream_serial_number); OggDemuxedTrack* demuxedTrack = fOurDemux->lookupDemuxedTrack(bitstream_serial_number); if (demuxedTrack == NULL) { // this track is not being read #ifdef DEBUG fprintf(stderr, "\tIgnoring page from unread track; skipping %d remaining packet data bytes\n", fPacketSizeTable->totSizes); #endif skipBytes(fPacketSizeTable->totSizes); return True; } else if (fPacketSizeTable->totSizes == 0) { // This page is empty (has no packets). Skip it and continue #ifdef DEBUG fprintf(stderr, "\t[track: %s] Skipping empty page\n", demuxedTrack->MIMEtype()); #endif return True; } // Start delivering packets next: demuxedTrack->fCurrentPageIsContinuation = (header_type_flag&0x01) != 0; fCurrentTrackNumber = bitstream_serial_number; fCurrentParseState = DELIVERING_PACKET_WITHIN_PAGE; saveParserState(); return False; } Boolean OggFileParser::deliverPacketWithinPage() { OggDemuxedTrack* demuxedTrack = fOurDemux->lookupDemuxedTrack(fCurrentTrackNumber); if (demuxedTrack == NULL) return False; // should not happen unsigned packetNum = fPacketSizeTable->nextPacketNumToDeliver; unsigned packetSize = fPacketSizeTable->size[packetNum]; if (!demuxedTrack->isCurrentlyAwaitingData()) { // Someone has been reading this stream, but isn't right now. // We can't deliver this frame until he asks for it, so punt for now. // The next time he asks for a frame, he'll get it. #ifdef DEBUG fprintf(stderr, "\t[track: %s] Deferring delivery of packet %d (%d bytes%s)\n", demuxedTrack->MIMEtype(), packetNum, packetSize, packetNum == fPacketSizeTable->numCompletedPackets ? " (incomplete)" : ""); #endif return True; } // Deliver the next packet: #ifdef DEBUG fprintf(stderr, "\t[track: %s] Delivering packet %d (%d bytes%s)\n", demuxedTrack->MIMEtype(), packetNum, packetSize, packetNum == fPacketSizeTable->numCompletedPackets ? " (incomplete)" : ""); #endif unsigned numBytesDelivered = packetSize < demuxedTrack->maxSize() ? packetSize : demuxedTrack->maxSize(); getBytes(demuxedTrack->to(), numBytesDelivered); u_int8_t firstByte = numBytesDelivered > 0 ? demuxedTrack->to()[0] : 0x00; u_int8_t secondByte = numBytesDelivered > 1 ? demuxedTrack->to()[1] : 0x00; demuxedTrack->to() += numBytesDelivered; if (demuxedTrack->fCurrentPageIsContinuation) { // the previous page's read was incomplete demuxedTrack->frameSize() += numBytesDelivered; } else { // This is the first delivery for this "doGetNextFrame()" call. demuxedTrack->frameSize() = numBytesDelivered; } if (packetSize > demuxedTrack->maxSize()) { demuxedTrack->numTruncatedBytes() += packetSize - demuxedTrack->maxSize(); } demuxedTrack->maxSize() -= numBytesDelivered; // Figure out the duration and presentation time of this frame. unsigned durationInMicroseconds; OggTrack* track = fOurFile.lookup(demuxedTrack->fOurTrackNumber); if (strcmp(track->mimeType, "audio/VORBIS") == 0) { if ((firstByte&0x01) != 0) { // This is a header packet durationInMicroseconds = 0; } else { // This is a data packet. // Parse the first byte to figure out its duration. // Extract the next "track->vtoHdrs.ilog_vorbis_mode_count_minus_1" bits of the first byte: u_int8_t const mask = 0xFE<<(track->vtoHdrs.ilog_vorbis_mode_count_minus_1); u_int8_t const modeNumber = (firstByte&~mask)>>1; if (modeNumber >= track->vtoHdrs.vorbis_mode_count) { fprintf(stderr, "Error: Bad mode number %d (>= vorbis_mode_count %d) in Vorbis packet!\n", modeNumber, track->vtoHdrs.vorbis_mode_count); durationInMicroseconds = 0; } else { unsigned blockNumber = track->vtoHdrs.vorbis_mode_blockflag[modeNumber]; durationInMicroseconds = track->vtoHdrs.uSecsPerPacket[blockNumber]; } } } else if (strcmp(track->mimeType, "video/THEORA") == 0) { if ((firstByte&0x80) != 0) { // This is a header packet durationInMicroseconds = 0; } else { // This is a data packet. durationInMicroseconds = track->vtoHdrs.uSecsPerFrame; } } else { // "audio/OPUS" if (firstByte == 0x4F/*'O'*/ && secondByte == 0x70/*'p*/) { // This is a header packet durationInMicroseconds = 0; } else { // This is a data packet. // Parse the first byte to figure out the duration of each frame, and then (if necessary) // parse the second byte to figure out how many frames are in this packet: u_int8_t config = firstByte >> 3; u_int8_t c = firstByte & 0x03; unsigned const configDuration[32] = { // in microseconds 10000, 20000, 40000, 60000, // config 0..3 10000, 20000, 40000, 60000, // config 4..7 10000, 20000, 40000, 60000, // config 8..11 10000, 20000, // config 12..13 10000, 20000, // config 14..15 2500, 5000, 10000, 20000, // config 16..19 2500, 5000, 10000, 20000, // config 20..23 2500, 5000, 10000, 20000, // config 24..27 2500, 5000, 10000, 20000 // config 28..31 }; unsigned const numFramesInPacket = c == 0 ? 1 : c == 3 ? (secondByte&0x3F) : 2; durationInMicroseconds = numFramesInPacket*configDuration[config]; } } if (demuxedTrack->nextPresentationTime().tv_sec == 0 && demuxedTrack->nextPresentationTime().tv_usec == 0) { // This is the first delivery. Initialize "demuxedTrack->nextPresentationTime()": gettimeofday(&demuxedTrack->nextPresentationTime(), NULL); } demuxedTrack->presentationTime() = demuxedTrack->nextPresentationTime(); demuxedTrack->durationInMicroseconds() = durationInMicroseconds; demuxedTrack->nextPresentationTime().tv_usec += durationInMicroseconds; while (demuxedTrack->nextPresentationTime().tv_usec >= 1000000) { ++demuxedTrack->nextPresentationTime().tv_sec; demuxedTrack->nextPresentationTime().tv_usec -= 1000000; } saveParserState(); // And check whether there's a next packet in this page: if (packetNum == fPacketSizeTable->numCompletedPackets) { // This delivery was for an incomplete packet, at the end of the page. // Return without completing delivery: fCurrentParseState = PARSING_AND_DELIVERING_PAGES; return False; } if (packetNum < fPacketSizeTable->numCompletedPackets-1 || fPacketSizeTable->lastPacketIsIncomplete) { // There is at least one more packet (possibly incomplete) left in this packet. // Deliver it next: ++fPacketSizeTable->nextPacketNumToDeliver; } else { // Start parsing a new page next: fCurrentParseState = PARSING_AND_DELIVERING_PAGES; } FramedSource::afterGetting(demuxedTrack); // completes delivery return True; } void OggFileParser::parseStartOfPage(u_int8_t& header_type_flag, u_int32_t& bitstream_serial_number) { saveParserState(); // First, make sure we start with the 'capture_pattern': 0x4F676753 ('OggS'): while (test4Bytes() != 0x4F676753) { skipBytes(1); saveParserState(); // ensures forward progress through the file } skipBytes(4); #ifdef DEBUG fprintf(stderr, "\nSaw Ogg page header:\n"); #endif u_int8_t stream_structure_version = get1Byte(); if (stream_structure_version != 0) { fprintf(stderr, "Saw page with unknown Ogg file version number: 0x%02x\n", stream_structure_version); } header_type_flag = get1Byte(); #ifdef DEBUG fprintf(stderr, "\theader_type_flag: 0x%02x (", header_type_flag); if (header_type_flag&0x01) fprintf(stderr, "continuation "); if (header_type_flag&0x02) fprintf(stderr, "bos "); if (header_type_flag&0x04) fprintf(stderr, "eos "); fprintf(stderr, ")\n"); #endif u_int32_t granule_position1 = byteSwap(get4Bytes()); u_int32_t granule_position2 = byteSwap(get4Bytes()); bitstream_serial_number = byteSwap(get4Bytes()); u_int32_t page_sequence_number = byteSwap(get4Bytes()); u_int32_t CRC_checksum = byteSwap(get4Bytes()); u_int8_t number_page_segments = get1Byte(); #ifdef DEBUG fprintf(stderr, "\tgranule_position 0x%08x%08x, bitstream_serial_number 0x%08x, page_sequence_number 0x%08x, CRC_checksum 0x%08x, number_page_segments %d\n", granule_position2, granule_position1, bitstream_serial_number, page_sequence_number, CRC_checksum, number_page_segments); #else // Dummy statements to prevent 'unused variable' compiler warnings: #define DUMMY_STATEMENT(x) do {x = x;} while (0) DUMMY_STATEMENT(granule_position1); DUMMY_STATEMENT(granule_position2); DUMMY_STATEMENT(page_sequence_number); DUMMY_STATEMENT(CRC_checksum); #endif // Look at the "segment_table" to count the sizes of the packets in this page: delete fPacketSizeTable/*if any*/; fPacketSizeTable = new PacketSizeTable(number_page_segments); u_int8_t lacing_value = 0; #ifdef DEBUG fprintf(stderr, "\tsegment_table\n"); #endif for (unsigned i = 0; i < number_page_segments; ++i) { lacing_value = get1Byte(); #ifdef DEBUG fprintf(stderr, "\t\t%d:\t%d", i, lacing_value); #endif fPacketSizeTable->totSizes += lacing_value; fPacketSizeTable->size[fPacketSizeTable->numCompletedPackets] += lacing_value; if (lacing_value < 255) { // This completes a packet: #ifdef DEBUG fprintf(stderr, " (->%d)", fPacketSizeTable->size[fPacketSizeTable->numCompletedPackets]); #endif ++fPacketSizeTable->numCompletedPackets; } #ifdef DEBUG fprintf(stderr, "\n"); #endif } fPacketSizeTable->lastPacketIsIncomplete = lacing_value == 255; }