750 lines
19 KiB
C++
750 lines
19 KiB
C++
// Copyright (c) 2012 The WebM project authors. All Rights Reserved.
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//
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// Use of this source code is governed by a BSD-style license
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// that can be found in the LICENSE file in the root of the source
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// tree. An additional intellectual property rights grant can be found
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// in the file PATENTS. All contributing project authors may
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// be found in the AUTHORS file in the root of the source tree.
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#include "mkvmuxerutil.hpp"
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#ifdef __ANDROID__
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#include <fcntl.h>
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#endif
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#include <cassert>
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#include <cmath>
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#include <cstdio>
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#ifdef _MSC_VER
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#define _CRT_RAND_S
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#endif
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#include <cstdlib>
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#include <cstring>
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#include <ctime>
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#include <new>
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#include "mkvwriter.hpp"
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#include "webmids.hpp"
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namespace mkvmuxer {
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namespace {
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// Date elements are always 8 octets in size.
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const int kDateElementSize = 8;
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} // namespace
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int32 GetCodedUIntSize(uint64 value) {
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if (value < 0x000000000000007FULL)
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return 1;
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else if (value < 0x0000000000003FFFULL)
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return 2;
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else if (value < 0x00000000001FFFFFULL)
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return 3;
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else if (value < 0x000000000FFFFFFFULL)
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return 4;
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else if (value < 0x00000007FFFFFFFFULL)
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return 5;
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else if (value < 0x000003FFFFFFFFFFULL)
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return 6;
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else if (value < 0x0001FFFFFFFFFFFFULL)
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return 7;
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return 8;
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}
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int32 GetUIntSize(uint64 value) {
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if (value < 0x0000000000000100ULL)
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return 1;
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else if (value < 0x0000000000010000ULL)
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return 2;
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else if (value < 0x0000000001000000ULL)
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return 3;
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else if (value < 0x0000000100000000ULL)
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return 4;
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else if (value < 0x0000010000000000ULL)
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return 5;
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else if (value < 0x0001000000000000ULL)
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return 6;
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else if (value < 0x0100000000000000ULL)
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return 7;
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return 8;
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}
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uint64 EbmlMasterElementSize(uint64 type, uint64 value) {
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// Size of EBML ID
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int32 ebml_size = GetUIntSize(type);
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// Datasize
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ebml_size += GetCodedUIntSize(value);
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return ebml_size;
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}
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uint64 EbmlElementSize(uint64 type, int64 value) {
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return EbmlElementSize(type, static_cast<uint64>(value));
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}
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uint64 EbmlElementSize(uint64 type, uint64 value) {
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// Size of EBML ID
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int32 ebml_size = GetUIntSize(type);
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// Datasize
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ebml_size += GetUIntSize(value);
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// Size of Datasize
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ebml_size++;
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return ebml_size;
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}
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uint64 EbmlElementSize(uint64 type, float /* value */ ) {
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// Size of EBML ID
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uint64 ebml_size = GetUIntSize(type);
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// Datasize
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ebml_size += sizeof(float);
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// Size of Datasize
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ebml_size++;
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return ebml_size;
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}
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uint64 EbmlElementSize(uint64 type, const char* value) {
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if (!value)
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return 0;
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// Size of EBML ID
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uint64 ebml_size = GetUIntSize(type);
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// Datasize
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ebml_size += strlen(value);
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// Size of Datasize
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ebml_size++;
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return ebml_size;
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}
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uint64 EbmlElementSize(uint64 type, const uint8* value, uint64 size) {
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if (!value)
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return 0;
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// Size of EBML ID
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uint64 ebml_size = GetUIntSize(type);
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// Datasize
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ebml_size += size;
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// Size of Datasize
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ebml_size += GetCodedUIntSize(size);
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return ebml_size;
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}
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uint64 EbmlDateElementSize(uint64 type, int64 value) {
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// Size of EBML ID
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uint64 ebml_size = GetUIntSize(type);
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// Datasize
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ebml_size += kDateElementSize;
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// Size of Datasize
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ebml_size++;
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return ebml_size;
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}
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int32 SerializeInt(IMkvWriter* writer, int64 value, int32 size) {
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if (!writer || size < 1 || size > 8)
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return -1;
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for (int32 i = 1; i <= size; ++i) {
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const int32 byte_count = size - i;
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const int32 bit_count = byte_count * 8;
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const int64 bb = value >> bit_count;
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const uint8 b = static_cast<uint8>(bb);
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const int32 status = writer->Write(&b, 1);
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if (status < 0)
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return status;
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}
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return 0;
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}
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int32 SerializeFloat(IMkvWriter* writer, float f) {
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if (!writer)
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return -1;
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assert(sizeof(uint32) == sizeof(float));
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// This union is merely used to avoid a reinterpret_cast from float& to
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// uint32& which will result in violation of strict aliasing.
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union U32 {
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uint32 u32;
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float f;
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} value;
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value.f = f;
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for (int32 i = 1; i <= 4; ++i) {
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const int32 byte_count = 4 - i;
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const int32 bit_count = byte_count * 8;
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const uint8 byte = static_cast<uint8>(value.u32 >> bit_count);
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const int32 status = writer->Write(&byte, 1);
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if (status < 0)
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return status;
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}
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return 0;
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}
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int32 WriteUInt(IMkvWriter* writer, uint64 value) {
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if (!writer)
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return -1;
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int32 size = GetCodedUIntSize(value);
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return WriteUIntSize(writer, value, size);
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}
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int32 WriteUIntSize(IMkvWriter* writer, uint64 value, int32 size) {
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if (!writer || size < 0 || size > 8)
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return -1;
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if (size > 0) {
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const uint64 bit = 1LL << (size * 7);
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if (value > (bit - 2))
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return -1;
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value |= bit;
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} else {
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size = 1;
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int64 bit;
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for (;;) {
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bit = 1LL << (size * 7);
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const uint64 max = bit - 2;
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if (value <= max)
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break;
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++size;
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}
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if (size > 8)
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return false;
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value |= bit;
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}
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return SerializeInt(writer, value, size);
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}
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int32 WriteID(IMkvWriter* writer, uint64 type) {
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if (!writer)
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return -1;
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writer->ElementStartNotify(type, writer->Position());
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const int32 size = GetUIntSize(type);
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return SerializeInt(writer, type, size);
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}
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bool WriteEbmlMasterElement(IMkvWriter* writer, uint64 type, uint64 size) {
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if (!writer)
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return false;
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if (WriteID(writer, type))
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return false;
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if (WriteUInt(writer, size))
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return false;
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return true;
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}
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bool WriteEbmlElement(IMkvWriter* writer, uint64 type, uint64 value) {
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if (!writer)
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return false;
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if (WriteID(writer, type))
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return false;
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const uint64 size = GetUIntSize(value);
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if (WriteUInt(writer, size))
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return false;
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if (SerializeInt(writer, value, static_cast<int32>(size)))
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return false;
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return true;
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}
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bool WriteEbmlElement(IMkvWriter* writer, uint64 type, float value) {
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if (!writer)
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return false;
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if (WriteID(writer, type))
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return false;
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if (WriteUInt(writer, 4))
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return false;
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if (SerializeFloat(writer, value))
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return false;
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return true;
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}
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bool WriteEbmlElement(IMkvWriter* writer, uint64 type, const char* value) {
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if (!writer || !value)
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return false;
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if (WriteID(writer, type))
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return false;
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const uint64 length = strlen(value);
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if (WriteUInt(writer, length))
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return false;
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if (writer->Write(value, static_cast<const uint32>(length)))
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return false;
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return true;
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}
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bool WriteEbmlElement(IMkvWriter* writer,
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uint64 type,
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const uint8* value,
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uint64 size) {
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if (!writer || !value || size < 1)
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return false;
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if (WriteID(writer, type))
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return false;
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if (WriteUInt(writer, size))
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return false;
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if (writer->Write(value, static_cast<uint32>(size)))
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return false;
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return true;
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}
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bool WriteEbmlDateElement(IMkvWriter* writer, uint64 type, int64 value) {
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if (!writer)
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return false;
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if (WriteID(writer, type))
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return false;
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if (WriteUInt(writer, kDateElementSize))
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return false;
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if (SerializeInt(writer, value, kDateElementSize))
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return false;
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return true;
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}
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uint64 WriteSimpleBlock(IMkvWriter* writer,
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const uint8* data,
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uint64 length,
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uint64 track_number,
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int64 timecode,
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uint64 is_key) {
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if (!writer)
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return false;
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if (!data || length < 1)
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return false;
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// Here we only permit track number values to be no greater than
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// 126, which the largest value we can store having a Matroska
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// integer representation of only 1 byte.
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if (track_number < 1 || track_number > 126)
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return false;
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// Technically the timestamp for a block can be less than the
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// timestamp for the cluster itself (remember that block timestamp
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// is a signed, 16-bit integer). However, as a simplification we
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// only permit non-negative cluster-relative timestamps for blocks.
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if (timecode < 0 || timecode > kMaxBlockTimecode)
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return false;
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if (WriteID(writer, kMkvSimpleBlock))
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return 0;
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const int32 size = static_cast<int32>(length) + 4;
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if (WriteUInt(writer, size))
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return 0;
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if (WriteUInt(writer, static_cast<uint64>(track_number)))
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return 0;
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if (SerializeInt(writer, timecode, 2))
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return 0;
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uint64 flags = 0;
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if (is_key)
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flags |= 0x80;
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if (SerializeInt(writer, flags, 1))
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return 0;
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if (writer->Write(data, static_cast<uint32>(length)))
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return 0;
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const uint64 element_size =
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GetUIntSize(kMkvSimpleBlock) + GetCodedUIntSize(size) + 4 + length;
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return element_size;
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}
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// We must write the metadata (key)frame as a BlockGroup element,
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// because we need to specify a duration for the frame. The
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// BlockGroup element comprises the frame itself and its duration,
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// and is laid out as follows:
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//
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// BlockGroup tag
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// BlockGroup size
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// Block tag
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// Block size
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// (the frame is the block payload)
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// Duration tag
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// Duration size
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// (duration payload)
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//
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uint64 WriteMetadataBlock(IMkvWriter* writer,
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const uint8* data,
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uint64 length,
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uint64 track_number,
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int64 timecode,
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uint64 duration) {
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// We don't backtrack when writing to the stream, so we must
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// pre-compute the BlockGroup size, by summing the sizes of each
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// sub-element (the block and the duration).
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// We use a single byte for the track number of the block, which
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// means the block header is exactly 4 bytes.
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// TODO(matthewjheaney): use EbmlMasterElementSize and WriteEbmlMasterElement
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const uint64 block_payload_size = 4 + length;
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const int32 block_size = GetCodedUIntSize(block_payload_size);
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const uint64 block_elem_size = 1 + block_size + block_payload_size;
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const int32 duration_payload_size = GetUIntSize(duration);
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const int32 duration_size = GetCodedUIntSize(duration_payload_size);
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const uint64 duration_elem_size = 1 + duration_size + duration_payload_size;
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const uint64 blockg_payload_size = block_elem_size + duration_elem_size;
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const int32 blockg_size = GetCodedUIntSize(blockg_payload_size);
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const uint64 blockg_elem_size = 1 + blockg_size + blockg_payload_size;
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if (WriteID(writer, kMkvBlockGroup)) // 1-byte ID size
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return 0;
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if (WriteUInt(writer, blockg_payload_size))
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return 0;
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// Write Block element
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if (WriteID(writer, kMkvBlock)) // 1-byte ID size
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return 0;
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if (WriteUInt(writer, block_payload_size))
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return 0;
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// Byte 1 of 4
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if (WriteUInt(writer, track_number))
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return 0;
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// Bytes 2 & 3 of 4
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if (SerializeInt(writer, timecode, 2))
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return 0;
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// Byte 4 of 4
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const uint64 flags = 0;
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if (SerializeInt(writer, flags, 1))
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return 0;
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// Now write the actual frame (of metadata)
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if (writer->Write(data, static_cast<uint32>(length)))
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return 0;
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// Write Duration element
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if (WriteID(writer, kMkvBlockDuration)) // 1-byte ID size
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return 0;
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if (WriteUInt(writer, duration_payload_size))
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return 0;
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if (SerializeInt(writer, duration, duration_payload_size))
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return 0;
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// Note that we don't write a reference time as part of the block
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// group; no reference time(s) indicates that this block is a
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// keyframe. (Unlike the case for a SimpleBlock element, the header
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// bits of the Block sub-element of a BlockGroup element do not
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// indicate keyframe status. The keyframe status is inferred from
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// the absence of reference time sub-elements.)
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return blockg_elem_size;
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}
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// Writes a WebM BlockGroup with BlockAdditional data. The structure is as
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// follows:
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// Indentation shows sub-levels
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// BlockGroup
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// Block
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// Data
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// BlockAdditions
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// BlockMore
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// BlockAddID
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// 1 (Denotes Alpha)
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// BlockAdditional
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// Data
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uint64 WriteBlockWithAdditional(IMkvWriter* writer,
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const uint8* data,
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uint64 length,
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const uint8* additional,
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uint64 additional_length,
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uint64 add_id,
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uint64 track_number,
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int64 timecode,
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uint64 is_key) {
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if (!data || !additional || length < 1 || additional_length < 1)
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return 0;
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const uint64 block_payload_size = 4 + length;
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const uint64 block_elem_size = EbmlMasterElementSize(kMkvBlock,
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block_payload_size) +
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block_payload_size;
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const uint64 block_additional_elem_size = EbmlElementSize(kMkvBlockAdditional,
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additional,
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additional_length);
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const uint64 block_addid_elem_size = EbmlElementSize(kMkvBlockAddID, add_id);
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const uint64 block_more_payload_size = block_addid_elem_size +
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block_additional_elem_size;
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const uint64 block_more_elem_size = EbmlMasterElementSize(
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kMkvBlockMore,
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block_more_payload_size) +
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block_more_payload_size;
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const uint64 block_additions_payload_size = block_more_elem_size;
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const uint64 block_additions_elem_size = EbmlMasterElementSize(
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kMkvBlockAdditions,
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block_additions_payload_size) +
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block_additions_payload_size;
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const uint64 block_group_payload_size = block_elem_size +
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block_additions_elem_size;
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const uint64 block_group_elem_size = EbmlMasterElementSize(
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kMkvBlockGroup,
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block_group_payload_size) +
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block_group_payload_size;
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if (!WriteEbmlMasterElement(writer, kMkvBlockGroup,
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block_group_payload_size))
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return 0;
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if (!WriteEbmlMasterElement(writer, kMkvBlock, block_payload_size))
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return 0;
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if (WriteUInt(writer, track_number))
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return 0;
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if (SerializeInt(writer, timecode, 2))
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return 0;
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uint64 flags = 0;
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if (is_key)
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flags |= 0x80;
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if (SerializeInt(writer, flags, 1))
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return 0;
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if (writer->Write(data, static_cast<uint32>(length)))
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return 0;
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if (!WriteEbmlMasterElement(writer, kMkvBlockAdditions,
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block_additions_payload_size))
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return 0;
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if (!WriteEbmlMasterElement(writer, kMkvBlockMore, block_more_payload_size))
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return 0;
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if (!WriteEbmlElement(writer, kMkvBlockAddID, add_id))
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return 0;
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if (!WriteEbmlElement(writer, kMkvBlockAdditional,
|
|
additional, additional_length))
|
|
return 0;
|
|
|
|
return block_group_elem_size;
|
|
}
|
|
|
|
// Writes a WebM BlockGroup with DiscardPadding. The structure is as follows:
|
|
// Indentation shows sub-levels
|
|
// BlockGroup
|
|
// Block
|
|
// Data
|
|
// DiscardPadding
|
|
uint64 WriteBlockWithDiscardPadding(IMkvWriter* writer,
|
|
const uint8* data,
|
|
uint64 length,
|
|
int64 discard_padding,
|
|
uint64 track_number,
|
|
int64 timecode,
|
|
uint64 is_key) {
|
|
if (!data || length < 1 || discard_padding <= 0)
|
|
return 0;
|
|
|
|
const uint64 block_payload_size = 4 + length;
|
|
const uint64 block_elem_size = EbmlMasterElementSize(kMkvBlock,
|
|
block_payload_size) +
|
|
block_payload_size;
|
|
const uint64 discard_padding_elem_size = EbmlElementSize(kMkvDiscardPadding,
|
|
discard_padding);
|
|
const uint64 block_group_payload_size = block_elem_size +
|
|
discard_padding_elem_size;
|
|
const uint64 block_group_elem_size = EbmlMasterElementSize(
|
|
kMkvBlockGroup,
|
|
block_group_payload_size) +
|
|
block_group_payload_size;
|
|
|
|
if (!WriteEbmlMasterElement(writer, kMkvBlockGroup,
|
|
block_group_payload_size))
|
|
return 0;
|
|
|
|
if (!WriteEbmlMasterElement(writer, kMkvBlock, block_payload_size))
|
|
return 0;
|
|
|
|
if (WriteUInt(writer, 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;
|
|
|
|
if (WriteID(writer, kMkvDiscardPadding))
|
|
return 0;
|
|
|
|
const uint64 size = GetUIntSize(discard_padding);
|
|
if (WriteUInt(writer, size))
|
|
return false;
|
|
|
|
if (SerializeInt(writer, discard_padding, static_cast<int32>(size)))
|
|
return false;
|
|
|
|
return block_group_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;
|
|
|
|
#ifdef __MINGW32__
|
|
srand(*seed);
|
|
#endif
|
|
|
|
for (int i = 0; i < 7; ++i) { // avoid problems with 8-byte values
|
|
uid <<= 8;
|
|
|
|
// TODO(fgalligan): Move random number generation to platform specific code.
|
|
#ifdef _MSC_VER
|
|
(void)seed;
|
|
unsigned int random_value;
|
|
const errno_t e = rand_s(&random_value);
|
|
(void)e;
|
|
const int32 nn = random_value;
|
|
#elif __ANDROID__
|
|
int32 temp_num = 1;
|
|
int fd = open("/dev/urandom", O_RDONLY);
|
|
if (fd != -1) {
|
|
read(fd, &temp_num, sizeof(int32));
|
|
close(fd);
|
|
}
|
|
const int32 nn = temp_num;
|
|
#elif defined __MINGW32__
|
|
const int32 nn = rand();
|
|
#else
|
|
const int32 nn = rand_r(seed);
|
|
#endif
|
|
const int32 n = 0xFF & (nn >> 4); // throw away low-order bits
|
|
|
|
uid |= n;
|
|
}
|
|
|
|
return uid;
|
|
}
|