shaka-packager/packager/media/formats/webm/webm_info_parser.cc

113 lines
2.6 KiB
C++

// Copyright 2014 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include <packager/media/formats/webm/webm_info_parser.h>
#include <ctime>
#include <absl/log/log.h>
#include <packager/macros.h>
#include <packager/media/formats/webm/webm_constants.h>
namespace shaka {
namespace media {
// Default timecode scale if the TimecodeScale element is
// not specified in the INFO element.
static const int kWebMDefaultTimecodeScale = 1000000;
WebMInfoParser::WebMInfoParser()
: timecode_scale_(-1),
duration_(-1) {
}
WebMInfoParser::~WebMInfoParser() {}
int WebMInfoParser::Parse(const uint8_t* buf, int size) {
timecode_scale_ = -1;
duration_ = -1;
WebMListParser parser(kWebMIdInfo, this);
int result = parser.Parse(buf, size);
if (result <= 0)
return result;
// For now we do all or nothing parsing.
return parser.IsParsingComplete() ? result : 0;
}
WebMParserClient* WebMInfoParser::OnListStart(int /*id*/) {
return this;
}
bool WebMInfoParser::OnListEnd(int id) {
if (id == kWebMIdInfo && timecode_scale_ == -1) {
// Set timecode scale to default value if it isn't present in
// the Info element.
timecode_scale_ = kWebMDefaultTimecodeScale;
}
return true;
}
bool WebMInfoParser::OnUInt(int id, int64_t val) {
if (id != kWebMIdTimecodeScale)
return true;
if (timecode_scale_ != -1) {
DVLOG(1) << "Multiple values for id " << std::hex << id << " specified";
return false;
}
timecode_scale_ = val;
return true;
}
bool WebMInfoParser::OnFloat(int id, double val) {
if (id != kWebMIdDuration) {
DVLOG(1) << "Unexpected float for id" << std::hex << id;
return false;
}
if (duration_ != -1) {
DVLOG(1) << "Multiple values for duration.";
return false;
}
duration_ = val;
return true;
}
bool WebMInfoParser::OnBinary(int id, const uint8_t* data, int size) {
if (id == kWebMIdDateUTC) {
if (size != 8)
return false;
int64_t date_in_nanoseconds = 0;
for (int i = 0; i < size; ++i)
date_in_nanoseconds = (date_in_nanoseconds << 8) | data[i];
std::tm exploded_epoch;
exploded_epoch.tm_year = 2001;
exploded_epoch.tm_mon = 1;
exploded_epoch.tm_mday = 1;
exploded_epoch.tm_hour = 0;
exploded_epoch.tm_min = 0;
exploded_epoch.tm_sec = 0;
date_utc_ =
std::chrono::system_clock::from_time_t(std::mktime(&exploded_epoch)) +
std::chrono::microseconds(date_in_nanoseconds / 1000);
}
return true;
}
bool WebMInfoParser::OnString(int /*id*/, const std::string& /*str*/) {
return true;
}
} // namespace media
} // namespace shaka