| // Copyright (c) 2012 The WebM project authors. All Rights Reserved. |
| // |
| // Use of this source code is governed by a BSD-style license |
| // that can be found in the LICENSE file in the root of the source |
| // tree. An additional intellectual property rights grant can be found |
| // in the file PATENTS. All contributing project authors may |
| // be found in the AUTHORS file in the root of the source tree. |
| |
| #include "mkvmuxerutil.hpp" |
| |
| #include <cmath> |
| #include <cstdio> |
| #include <cstdlib> |
| #include <cstring> |
| #include <ctime> |
| |
| #include <limits> |
| #include <new> |
| |
| #include "mkvwriter.hpp" |
| #include "webmids.hpp" |
| |
| namespace mkvmuxer { |
| |
| int32 GetCodedUIntSize(uint64 value) { |
| if (value < 0x000000000000007FULL) |
| return 1; |
| else if (value < 0x0000000000003FFFULL) |
| return 2; |
| else if (value < 0x00000000001FFFFFULL) |
| return 3; |
| else if (value < 0x000000000FFFFFFFULL) |
| return 4; |
| else if (value < 0x00000007FFFFFFFFULL) |
| return 5; |
| else if (value < 0x000003FFFFFFFFFFULL) |
| return 6; |
| else if (value < 0x0001FFFFFFFFFFFFULL) |
| return 7; |
| return 8; |
| } |
| |
| int32 GetUIntSize(uint64 value) { |
| if (value < 0x0000000000000100ULL) |
| return 1; |
| else if (value < 0x0000000000010000ULL) |
| return 2; |
| else if (value < 0x0000000001000000ULL) |
| return 3; |
| else if (value < 0x0000000100000000ULL) |
| return 4; |
| else if (value < 0x0000010000000000ULL) |
| return 5; |
| else if (value < 0x0001000000000000ULL) |
| return 6; |
| else if (value < 0x0100000000000000ULL) |
| return 7; |
| return 8; |
| } |
| |
| uint64 EbmlMasterElementSize(uint64 type, uint64 value) { |
| // Size of EBML ID |
| int32 ebml_size = GetUIntSize(type); |
| |
| // Datasize |
| ebml_size += GetCodedUIntSize(value); |
| |
| return ebml_size; |
| } |
| |
| uint64 EbmlElementSize(uint64 type, uint64 value) { |
| // Size of EBML ID |
| int32 ebml_size = GetUIntSize(type); |
| |
| // Datasize |
| ebml_size += GetUIntSize(value); |
| |
| // Size of Datasize |
| ebml_size++; |
| |
| return ebml_size; |
| } |
| |
| uint64 EbmlElementSize(uint64 type, float value) { |
| // Size of EBML ID |
| uint64 ebml_size = GetUIntSize(type); |
| |
| // Datasize |
| ebml_size += sizeof(value); |
| |
| // Size of Datasize |
| ebml_size++; |
| |
| return ebml_size; |
| } |
| |
| uint64 EbmlElementSize(uint64 type, const char* value) { |
| if (!value) |
| return 0; |
| |
| // Size of EBML ID |
| uint64 ebml_size = GetUIntSize(type); |
| |
| // Datasize |
| ebml_size += strlen(value); |
| |
| // Size of Datasize |
| ebml_size++; |
| |
| return ebml_size; |
| } |
| |
| uint64 EbmlElementSize(uint64 type, const uint8* value, uint64 size) { |
| if (!value) |
| return 0; |
| |
| // Size of EBML ID |
| uint64 ebml_size = GetUIntSize(type); |
| |
| // Datasize |
| ebml_size += size; |
| |
| // Size of Datasize |
| ebml_size += GetCodedUIntSize(size); |
| |
| return ebml_size; |
| } |
| |
| int32 SerializeInt(IMkvWriter* writer, int64 value, int32 size) { |
| if (!writer || size < 1 || size > 8) |
| return -1; |
| |
| for (int32 i = 1; i <= size; ++i) { |
| const int32 byte_count = size - i; |
| const int32 bit_count = byte_count * 8; |
| |
| const int64 bb = value >> bit_count; |
| const uint8 b = static_cast<uint8>(bb); |
| |
| const int32 status = writer->Write(&b, 1); |
| |
| if (status < 0) |
| return status; |
| } |
| |
| return 0; |
| } |
| |
| int32 SerializeFloat(IMkvWriter* writer, float f) { |
| if (!writer) |
| return -1; |
| |
| const uint32& val = reinterpret_cast<const uint32&>(f); |
| |
| for (int32 i = 1; i <= 4; ++i) { |
| const int32 byte_count = 4 - i; |
| const int32 bit_count = byte_count * 8; |
| |
| const uint32 bb = val >> bit_count; |
| const uint8 b = static_cast<uint8>(bb); |
| |
| const int32 status = writer->Write(&b, 1); |
| |
| if (status < 0) |
| return status; |
| } |
| |
| return 0; |
| } |
| |
| int32 WriteUInt(IMkvWriter* writer, uint64 value) { |
| if (!writer) |
| return -1; |
| |
| int32 size = GetCodedUIntSize(value); |
| |
| return WriteUIntSize(writer, value, size); |
| } |
| |
| int32 WriteUIntSize(IMkvWriter* writer, uint64 value, int32 size) { |
| if (!writer || size < 0 || size > 8) |
| return -1; |
| |
| if (size > 0) { |
| const uint64 bit = 1LL << (size * 7); |
| |
| if (value > (bit - 2)) |
| return -1; |
| |
| value |= bit; |
| } else { |
| size = 1; |
| int64 bit; |
| |
| for (;;) { |
| bit = 1LL << (size * 7); |
| const uint64 max = bit - 2; |
| |
| if (value <= max) |
| break; |
| |
| ++size; |
| } |
| |
| if (size > 8) |
| return false; |
| |
| value |= bit; |
| } |
| |
| return SerializeInt(writer, value, size); |
| } |
| |
| int32 WriteID(IMkvWriter* writer, uint64 type) { |
| if (!writer) |
| return -1; |
| |
| writer->ElementStartNotify(type, writer->Position()); |
| |
| const int32 size = GetUIntSize(type); |
| |
| return SerializeInt(writer, type, size); |
| } |
| |
| bool WriteEbmlMasterElement(IMkvWriter* writer, uint64 type, uint64 size) { |
| if (!writer) |
| return false; |
| |
| if (WriteID(writer, type)) |
| return false; |
| |
| if (WriteUInt(writer, size)) |
| return false; |
| |
| return true; |
| } |
| |
| bool WriteEbmlElement(IMkvWriter* writer, uint64 type, uint64 value) { |
| if (!writer) |
| return false; |
| |
| if (WriteID(writer, type)) |
| return false; |
| |
| const uint64 size = GetUIntSize(value); |
| if (WriteUInt(writer, size)) |
| return false; |
| |
| if (SerializeInt(writer, value, static_cast<int32>(size))) |
| return false; |
| |
| return true; |
| } |
| |
| bool WriteEbmlElement(IMkvWriter* writer, uint64 type, float value) { |
| if (!writer) |
| return false; |
| |
| if (WriteID(writer, type)) |
| return false; |
| |
| if (WriteUInt(writer, 4)) |
| return false; |
| |
| if (SerializeFloat(writer, value)) |
| return false; |
| |
| return true; |
| } |
| |
| bool WriteEbmlElement(IMkvWriter* writer, uint64 type, const char* value) { |
| if (!writer || !value) |
| return false; |
| |
| if (WriteID(writer, type)) |
| return false; |
| |
| const int32 length = strlen(value); |
| if (WriteUInt(writer, length)) |
| return false; |
| |
| if (writer->Write(value, length)) |
| return false; |
| |
| return true; |
| } |
| |
| bool WriteEbmlElement(IMkvWriter* writer, |
| uint64 type, |
| const uint8* value, |
| uint64 size) { |
| if (!writer || !value || size < 1) |
| return false; |
| |
| if (WriteID(writer, type)) |
| return false; |
| |
| if (WriteUInt(writer, size)) |
| return false; |
| |
| if (writer->Write(value, static_cast<uint32>(size))) |
| return false; |
| |
| return true; |
| } |
| |
| uint64 WriteSimpleBlock(IMkvWriter* writer, |
| const uint8* data, |
| uint64 length, |
| uint64 track_number, |
| int64 timecode, |
| uint64 is_key) { |
| if (!writer) |
| return false; |
| |
| if (!data || length < 1) |
| return false; |
| |
| // Here we only permit track number values to be no greater than |
| // 126, which the largest value we can store having a Matroska |
| // integer representation of only 1 byte. |
| |
| if (track_number < 1 || track_number > 126) |
| return false; |
| |
| // Technically the timestamp for a block can be less than the |
| // timestamp for the cluster itself (remember that block timestamp |
| // is a signed, 16-bit integer). However, as a simplification we |
| // only permit non-negative cluster-relative timestamps for blocks. |
| |
| if (timecode < 0 || timecode > std::numeric_limits<int16>::max()) |
| return false; |
| |
| if (WriteID(writer, kMkvSimpleBlock)) |
| return 0; |
| |
| const int32 size = static_cast<int32>(length) + 4; |
| if (WriteUInt(writer, size)) |
| return 0; |
| |
| if (WriteUInt(writer, static_cast<uint64>(track_number))) |
| return 0; |
| |
| if (SerializeInt(writer, timecode, 2)) |
| return 0; |
| |
| uint64 flags = 0; |
| if (is_key) |
| flags |= 0x80; |
| |
| if (SerializeInt(writer, flags, 1)) |
| return 0; |
| |
| if (writer->Write(data, static_cast<uint32>(length))) |
| return 0; |
| |
| const uint64 element_size = |
| GetUIntSize(kMkvSimpleBlock) + GetCodedUIntSize(size) + 4 + length; |
| |
| return element_size; |
| } |
| |
| // We must write the metadata (key)frame as a BlockGroup element, |
| // because we need to specify a duration for the frame. The |
| // BlockGroup element comprises the frame itself and its duration, |
| // and is laid out as follows: |
| // |
| // BlockGroup tag |
| // BlockGroup size |
| // Block tag |
| // Block size |
| // (the frame is the block payload) |
| // Duration tag |
| // Duration size |
| // (duration payload) |
| // |
| uint64 WriteMetadataBlock(IMkvWriter* writer, |
| const uint8* data, |
| uint64 length, |
| uint64 track_number, |
| int64 timecode, |
| uint64 duration) { |
| // We don't backtrack when writing to the stream, so we must |
| // pre-compute the BlockGroup size, by summing the sizes of each |
| // sub-element (the block and the duration). |
| |
| // We use a single byte for the track number of the block, which |
| // means the block header is exactly 4 bytes. |
| |
| // TODO(matthewjheaney): use EbmlMasterElementSize and WriteEbmlMasterElement |
| |
| const uint64 block_payload_size = 4 + length; |
| const int32 block_size = GetCodedUIntSize(block_payload_size); |
| const uint64 block_elem_size = 1 + block_size + block_payload_size; |
| |
| const int32 duration_payload_size = GetUIntSize(duration); |
| const int32 duration_size = GetCodedUIntSize(duration_payload_size); |
| const uint64 duration_elem_size = 1 + duration_size + duration_payload_size; |
| |
| const uint64 blockg_payload_size = block_elem_size + duration_elem_size; |
| const int32 blockg_size = GetCodedUIntSize(blockg_payload_size); |
| const uint64 blockg_elem_size = 1 + blockg_size + blockg_payload_size; |
| |
| if (WriteID(writer, kMkvBlockGroup)) // 1-byte ID size |
| return 0; |
| |
| if (WriteUInt(writer, blockg_payload_size)) |
| return 0; |
| |
| // Write Block element |
| |
| if (WriteID(writer, kMkvBlock)) // 1-byte ID size |
| return 0; |
| |
| if (WriteUInt(writer, block_payload_size)) |
| return 0; |
| |
| // Byte 1 of 4 |
| |
| if (WriteUInt(writer, track_number)) |
| return 0; |
| |
| // Bytes 2 & 3 of 4 |
| |
| if (SerializeInt(writer, timecode, 2)) |
| return 0; |
| |
| // Byte 4 of 4 |
| |
| const uint64 flags = 0; |
| |
| if (SerializeInt(writer, flags, 1)) |
| return 0; |
| |
| // Now write the actual frame (of metadata) |
| |
| if (writer->Write(data, static_cast<uint32>(length))) |
| return 0; |
| |
| // Write Duration element |
| |
| if (WriteID(writer, kMkvBlockDuration)) // 1-byte ID size |
| return 0; |
| |
| if (WriteUInt(writer, duration_payload_size)) |
| return 0; |
| |
| if (SerializeInt(writer, duration, duration_payload_size)) |
| return 0; |
| |
| // Note that we don't write a reference time as part of the block |
| // group; no reference time(s) indicates that this block is a |
| // keyframe. (Unlike the case for a SimpleBlock element, the header |
| // bits of the Block sub-element of a BlockGroup element do not |
| // indicate keyframe status. The keyframe status is inferred from |
| // the absence of reference time sub-elements.) |
| |
| return blockg_elem_size; |
| } |
| |
| uint64 WriteVoidElement(IMkvWriter* writer, uint64 size) { |
| if (!writer) |
| return false; |
| |
| // Subtract one for the void ID and the coded size. |
| uint64 void_entry_size = size - 1 - GetCodedUIntSize(size-1); |
| uint64 void_size = EbmlMasterElementSize(kMkvVoid, void_entry_size) + |
| void_entry_size; |
| |
| if (void_size != size) |
| return 0; |
| |
| const int64 payload_position = writer->Position(); |
| if (payload_position < 0) |
| return 0; |
| |
| if (WriteID(writer, kMkvVoid)) |
| return 0; |
| |
| if (WriteUInt(writer, void_entry_size)) |
| return 0; |
| |
| const uint8 value = 0; |
| for (int32 i = 0; i < static_cast<int32>(void_entry_size); ++i) { |
| if (writer->Write(&value, 1)) |
| return 0; |
| } |
| |
| const int64 stop_position = writer->Position(); |
| if (stop_position < 0 || |
| stop_position - payload_position != static_cast<int64>(void_size)) |
| return 0; |
| |
| return void_size; |
| } |
| |
| void GetVersion(int32* major, int32* minor, int32* build, int32* revision) { |
| *major = 0; |
| *minor = 2; |
| *build = 1; |
| *revision = 0; |
| } |
| |
| } // namespace mkvmuxer |
| |
| mkvmuxer::uint64 mkvmuxer::MakeUID(unsigned int* seed) { |
| uint64 uid = 0; |
| for (int i = 0; i < 7; ++i) { // avoid problems with 8-byte values |
| uid <<= 8; |
| |
| const int32 nn = rand_r(seed); |
| const int32 n = 0xFF & (nn >> 4); // throw away low-order bits |
| |
| uid |= n; |
| } |
| |
| return uid; |
| } |