Tag Parser 10.3.0
C++ library for reading and writing MP4 (iTunes), ID3, Vorbis, Opus, FLAC and Matroska tags
oggstream.cpp
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1#include "./oggstream.h"
2#include "./oggcontainer.h"
3
4#include "../vorbis/vorbisidentificationheader.h"
5#include "../vorbis/vorbispackagetypes.h"
6
7#include "../opus/opusidentificationheader.h"
8
9#include "../flac/flactooggmappingheader.h"
10
11#include "../exceptions.h"
12#include "../mediafileinfo.h"
13#include "../mediaformat.h"
14
15#include <c++utilities/chrono/timespan.h>
16
17#include <functional>
18#include <iostream>
19
20using namespace std;
21using namespace std::placeholders;
22using namespace CppUtilities;
23
24namespace TagParser {
25
34OggStream::OggStream(OggContainer &container, vector<OggPage>::size_type startPage)
35 : AbstractTrack(container.stream(), container.m_iterator.pages()[startPage].startOffset())
36 , m_startPage(startPage)
37 , m_container(container)
38 , m_currentSequenceNumber(0)
39{
40}
41
46{
47}
48
50{
51 CPP_UTILITIES_UNUSED(progress)
52
53 static const string context("parsing OGG page header");
54
55 // read basic information from first page
56 OggIterator &iterator = m_container.m_iterator;
57 const OggPage &firstPage = iterator.pages()[m_startPage];
59 m_id = firstPage.streamSerialNumber();
60
61 // ensure iterator is setup properly
62 iterator.setFilter(firstPage.streamSerialNumber());
63 iterator.setPageIndex(m_startPage);
64
65 // iterate through segments using OggIterator
66 for (bool hasIdentificationHeader = false, hasCommentHeader = false; iterator && (!hasIdentificationHeader || !hasCommentHeader); ++iterator) {
67 const std::uint32_t currentSize = iterator.currentSegmentSize();
68 if (currentSize >= 8) {
69 // determine stream format
70 inputStream().seekg(static_cast<streamoff>(iterator.currentSegmentOffset()));
71 const std::uint64_t sig = reader().readUInt64BE();
72
73 if ((sig & 0x00ffffffffffff00u) == 0x00766F7262697300u) {
74 // Vorbis header detected
75 switch (m_format.general) {
79 break;
81 break;
82 default:
83 diag.emplace_back(DiagLevel::Warning, "Stream format is inconsistent.", context);
84 continue;
85 }
86
87 // check header type
88 switch (sig >> 56) {
90 if (!hasIdentificationHeader) {
91 // parse identification header
93 ind.parseHeader(iterator);
94 m_version = ind.version();
97 if (ind.nominalBitrate()) {
99 } else if (ind.maxBitrate() == ind.minBitrate()) {
100 m_bitrate = ind.maxBitrate();
101 }
102 if (m_bitrate != 0.0) {
103 m_bitrate /= 1000.0;
104 }
105 calculateDurationViaSampleCount();
106 hasIdentificationHeader = true;
107 } else {
108 diag.emplace_back(DiagLevel::Critical,
109 "Vorbis identification header appears more than once. Oversupplied occurrence will be ignored.", context);
110 }
111 break;
113 // Vorbis comment found -> notify container about comment
114 if (!hasCommentHeader) {
115 m_container.announceComment(iterator.currentPageIndex(), iterator.currentSegmentIndex(), false, GeneralMediaFormat::Vorbis);
116 hasCommentHeader = true;
117 } else {
118 diag.emplace_back(
119 DiagLevel::Critical, "Vorbis comment header appears more than once. Oversupplied occurrence will be ignored.", context);
120 }
121 break;
123 break; // TODO
124 default:;
125 }
126
127 } else if (sig == 0x4F70757348656164u) {
128 // Opus header detected
129 switch (m_format.general) {
133 break;
135 break;
136 default:
137 diag.emplace_back(DiagLevel::Warning, "Stream format is inconsistent.", context);
138 continue;
139 }
140 if (!hasIdentificationHeader) {
141 // parse identification header
143 ind.parseHeader(iterator);
144 m_version = ind.version();
145 m_channelCount = ind.channels();
147 calculateDurationViaSampleCount(ind.preSkip());
148 hasIdentificationHeader = true;
149 } else {
150 diag.emplace_back(
151 DiagLevel::Critical, "Opus identification header appears more than once. Oversupplied occurrence will be ignored.", context);
152 }
153
154 } else if (sig == 0x4F70757354616773u) {
155 // Opus comment detected
156 switch (m_format.general) {
160 break;
162 break;
163 default:
164 diag.emplace_back(DiagLevel::Warning, "Stream format is inconsistent.", context);
165 continue;
166 }
167
168 // notify container about comment
169 if (!hasCommentHeader) {
170 m_container.announceComment(iterator.currentPageIndex(), iterator.currentSegmentIndex(), false, GeneralMediaFormat::Opus);
171 hasCommentHeader = true;
172 } else {
173 diag.emplace_back(
174 DiagLevel::Critical, "Opus tags/comment header appears more than once. Oversupplied occurrence will be ignored.", context);
175 }
176
177 } else if ((sig & 0xFFFFFFFFFF000000u) == 0x7F464C4143000000u) {
178 // FLAC header detected
179 switch (m_format.general) {
183 break;
185 break;
186 default:
187 diag.emplace_back(DiagLevel::Warning, "Stream format is inconsistent.", context);
188 continue;
189 }
190
191 if (!hasIdentificationHeader) {
192 // parse FLAC-to-Ogg mapping header
194 const FlacMetaDataBlockStreamInfo &streamInfo = mapping.streamInfo();
195 mapping.parseHeader(iterator);
196 m_bitsPerSample = streamInfo.bitsPerSample();
197 m_channelCount = streamInfo.channelCount();
199 m_sampleCount = streamInfo.totalSampleCount();
200 calculateDurationViaSampleCount();
201 hasIdentificationHeader = true;
202 } else {
203 diag.emplace_back(
204 DiagLevel::Critical, "FLAC-to-Ogg mapping header appears more than once. Oversupplied occurrence will be ignored.", context);
205 }
206
207 if (!hasCommentHeader) {
208 // a Vorbis comment should be following
209 if (++iterator) {
210 char buff[4];
211 iterator.read(buff, 4);
213 header.parseHeader(buff);
215 m_container.announceComment(
216 iterator.currentPageIndex(), iterator.currentSegmentIndex(), header.isLast(), GeneralMediaFormat::Flac);
217 hasCommentHeader = true;
218 } else {
219 diag.emplace_back(
220 DiagLevel::Critical, "OGG page after FLAC-to-Ogg mapping header doesn't contain Vorbis comment.", context);
221 }
222 } else {
223 diag.emplace_back(
224 DiagLevel::Critical, "No more OGG pages after FLAC-to-Ogg mapping header (Vorbis comment expected).", context);
225 }
226 }
227
228 } else if ((sig & 0x00ffffffffffff00u) == 0x007468656F726100u) {
229 // Theora header detected
230 switch (m_format.general) {
234 break;
236 break;
237 default:
238 diag.emplace_back(DiagLevel::Warning, "Stream format is inconsistent.", context);
239 continue;
240 }
241 // TODO: read more information about Theora stream
242
243 } else if ((sig & 0xFFFFFFFFFFFF0000u) == 0x5370656578200000u) {
244 // Speex header detected
245 switch (m_format.general) {
249 break;
251 break;
252 default:
253 diag.emplace_back(DiagLevel::Warning, "Stream format is inconsistent.", context);
254 continue;
255 }
256 // TODO: read more information about Speex stream
257 } else if (sig == 0x595556344D504547u) {
258 // YUV4MPEG header detected
259 switch (m_format.general) {
263 m_chromaFormat = "YUV";
264 break;
266 break;
267 default:
268 diag.emplace_back(DiagLevel::Warning, "Stream format is inconsistent.", context);
269 continue;
270 }
271 // TODO: read more information about YUV4MPEG stream
272 }
273 // currently only Vorbis, Opus, Theora, Speex and YUV4MPEG can be detected, TODO: detect more formats
274
275 } else {
276 // just ignore segments of only 8 byte or even less
277 // TODO: print warning?
278 }
279
280 // TODO: reduce code duplication
281 }
282
283 // estimate duration from size and bitrate if sample count and sample rate could not be determined
284 if (m_duration.isNull() && m_size && m_bitrate != 0.0) {
285 // calculate duration from stream size and bitrate, assuming 1 % overhead
286 m_duration = TimeSpan::fromSeconds(static_cast<double>(m_size) / (m_bitrate * 125.0) * 1.1);
287 }
288}
289
290void OggStream::calculateDurationViaSampleCount(std::uint16_t preSkip)
291{
292 // define predicate for finding pages of this stream by its stream serial number
293 const auto pred = bind(&OggPage::matchesStreamSerialNumber, _1, m_id);
294
295 // determine sample count
296 const auto &iterator = m_container.m_iterator;
297 if (!m_sampleCount && iterator.isLastPageFetched()) {
298 const auto &pages = iterator.pages();
299 const auto firstPage = find_if(pages.cbegin(), pages.cend(), pred);
300 const auto lastPage = find_if(pages.crbegin(), pages.crend(), pred);
301 if (firstPage != pages.cend() && lastPage != pages.crend()) {
302 m_sampleCount = lastPage->absoluteGranulePosition() - firstPage->absoluteGranulePosition();
303 // must apply "pre-skip" here to calculate effective sample count and duration?
304 if (m_sampleCount > preSkip) {
305 m_sampleCount -= preSkip;
306 } else {
307 m_sampleCount = 0;
308 }
309 }
310 }
311
312 // actually calculate the duration
313 if (m_sampleCount && m_samplingFrequency != 0.0) {
314 m_duration = TimeSpan::fromSeconds(static_cast<double>(m_sampleCount) / m_samplingFrequency);
315 }
316}
317
318} // namespace TagParser
The AbortableProgressFeedback class provides feedback about an ongoing operation via callbacks.
The AbstractTrack class parses and stores technical information about video, audio and other kinds of...
Definition: abstracttrack.h:65
std::string_view m_chromaFormat
std::uint64_t m_sampleCount
std::uint16_t m_bitsPerSample
std::istream & inputStream()
Returns the associated input stream.
std::uint16_t m_channelCount
CppUtilities::BinaryReader & reader()
Returns a binary reader for the associated stream.
CppUtilities::TimeSpan m_duration
std::uint32_t m_samplingFrequency
The Diagnostics class is a container for DiagMessage.
Definition: diagnostics.h:156
The FlacMetaDataBlockHeader class is a FLAC "METADATA_BLOCK_HEADER" parser and maker.
Definition: flacmetadata.h:28
constexpr std::uint8_t type() const
Returns the block type.
Definition: flacmetadata.h:79
constexpr std::uint8_t isLast() const
Returns whether this is the last metadata block before the audio blocks.
Definition: flacmetadata.h:62
void parseHeader(std::string_view buffer)
Parses the FLAC "METADATA_BLOCK_HEADER" which is read using the specified iterator.
The FlacMetaDataBlockStreamInfo class is a FLAC "METADATA_BLOCK_STREAMINFO" parser.
Definition: flacmetadata.h:109
constexpr std::uint64_t totalSampleCount() const
Returns the total samples in stream.
Definition: flacmetadata.h:232
constexpr std::uint32_t samplingFrequency() const
Returns the sampling frequency in Hz.
Definition: flacmetadata.h:197
constexpr std::uint8_t bitsPerSample() const
Returns the bits per sample.
Definition: flacmetadata.h:219
constexpr std::uint8_t channelCount() const
Returns the number of channels.
Definition: flacmetadata.h:207
The FlacToOggMappingHeader class is a FLAC-to-Ogg mapping header parser.
constexpr const FlacMetaDataBlockStreamInfo & streamInfo() const
Returns the stream info.
void parseHeader(OggIterator &iterator)
Parses the FLAC-to-Ogg mapping header which is read using the specified iterator.
GeneralMediaFormat general
Definition: mediaformat.h:259
Implementation of TagParser::AbstractContainer for OGG files.
Definition: oggcontainer.h:129
The OggIterator class helps iterating through all segments of an OGG bitstream.
Definition: oggiterator.h:11
void read(char *buffer, std::size_t count)
Reads count bytes from the OGG stream and writes it to the specified buffer.
std::vector< std::uint32_t >::size_type currentSegmentIndex() const
Returns the index of the current segment (in the current page) if the iterator is valid; otherwise an...
Definition: oggiterator.h:204
std::uint64_t currentSegmentOffset() const
Returns the start offset of the current segment in the input stream if the iterator is valid; otherwi...
Definition: oggiterator.h:213
const std::vector< OggPage > & pages() const
Returns a vector of containing the OGG pages that have been fetched yet.
Definition: oggiterator.h:125
void setPageIndex(std::vector< OggPage >::size_type index)
Sets the current page index.
Definition: oggiterator.h:183
std::vector< OggPage >::size_type currentPageIndex() const
Returns the index of the current page if the iterator is valid; otherwise an undefined index is retur...
Definition: oggiterator.h:174
std::uint32_t currentSegmentSize() const
Returns the size of the current segment.
Definition: oggiterator.h:240
void setFilter(std::uint32_t streamSerialId)
Allows to filter pages by the specified streamSerialId.
Definition: oggiterator.h:269
The OggPage class is used to parse OGG pages.
Definition: oggpage.h:13
std::uint32_t streamSerialNumber() const
Returns the stream serial number.
Definition: oggpage.h:164
bool matchesStreamSerialNumber(std::uint32_t streamSerialNumber) const
Returns whether the stream serial number of the current instance matches the specified one.
Definition: oggpage.h:173
std::uint8_t streamStructureVersion() const
Returns the stream structure version.
Definition: oggpage.h:92
~OggStream() override
Destroys the track.
Definition: oggstream.cpp:45
OggStream(OggContainer &container, std::vector< OggPage >::size_type startPage)
Constructs a new track for the stream at the specified startOffset.
Definition: oggstream.cpp:34
void internalParseHeader(Diagnostics &diag, AbortableProgressFeedback &progress) override
This method is internally called to parse header information.
Definition: oggstream.cpp:49
The OpusIdentificationHeader class is an Opus identification header parser.
constexpr std::uint16_t preSkip() const
Returns "pre-skip" value for the Opus stream.
constexpr std::uint8_t channels() const
Returns the number of channels for the Opus stream.
constexpr std::uint8_t version() const
Returns the version (which should be 1 currently).
constexpr std::uint32_t sampleRate() const
Returns the INPUT sample rate.
void parseHeader(OggIterator &iterator)
Parses the Opus identification header which is read using the specified iterator.
The VorbisIdentificationHeader class is a Vorbis identification header parser.
constexpr std::uint32_t sampleRate() const
constexpr std::uint32_t minBitrate() const
void parseHeader(OggIterator &iterator)
Parses the Vorbis identification header which is read using the specified iterator.
constexpr std::uint32_t maxBitrate() const
constexpr std::uint32_t nominalBitrate() const
Contains all classes and functions of the TagInfo library.
Definition: aaccodebook.h:10