shaka-packager/packager/mpd/base/xml/xml_node.cc

411 lines
14 KiB
C++

// Copyright 2014 Google Inc. All rights reserved.
//
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file or at
// https://developers.google.com/open-source/licenses/bsd
#include "packager/mpd/base/xml/xml_node.h"
#include <limits>
#include <set>
#include "packager/base/logging.h"
#include "packager/base/macros.h"
#include "packager/base/strings/string_number_conversions.h"
#include "packager/base/sys_byteorder.h"
#include "packager/mpd/base/media_info.pb.h"
#include "packager/mpd/base/mpd_utils.h"
#include "packager/mpd/base/segment_info.h"
namespace shaka {
using xml::XmlNode;
typedef MediaInfo::AudioInfo AudioInfo;
typedef MediaInfo::VideoInfo VideoInfo;
namespace {
const char kEC3Codec[] = "ec-3";
std::string RangeToString(const Range& range) {
return base::Uint64ToString(range.begin()) + "-" +
base::Uint64ToString(range.end());
}
bool PopulateSegmentTimeline(const std::list<SegmentInfo>& segment_infos,
XmlNode* segment_timeline) {
for (std::list<SegmentInfo>::const_iterator it = segment_infos.begin();
it != segment_infos.end();
++it) {
XmlNode s_element("S");
s_element.SetIntegerAttribute("t", it->start_time);
s_element.SetIntegerAttribute("d", it->duration);
if (it->repeat > 0)
s_element.SetIntegerAttribute("r", it->repeat);
CHECK(segment_timeline->AddChild(s_element.PassScopedPtr()));
}
return true;
}
} // namespace
namespace xml {
XmlNode::XmlNode(const char* name) : node_(xmlNewNode(NULL, BAD_CAST name)) {
DCHECK(name);
DCHECK(node_);
}
XmlNode::~XmlNode() {}
bool XmlNode::AddChild(scoped_xml_ptr<xmlNode> child) {
DCHECK(node_);
DCHECK(child);
if (!xmlAddChild(node_.get(), child.get()))
return false;
// Reaching here means the ownership of |child| transfered to |node_|.
// Release the pointer so that it doesn't get destructed in this scope.
ignore_result(child.release());
return true;
}
bool XmlNode::AddElements(const std::vector<Element>& elements) {
for (size_t element_index = 0; element_index < elements.size();
++element_index) {
const Element& child_element = elements[element_index];
XmlNode child_node(child_element.name.c_str());
for (std::map<std::string, std::string>::const_iterator attribute_it =
child_element.attributes.begin();
attribute_it != child_element.attributes.end(); ++attribute_it) {
child_node.SetStringAttribute(attribute_it->first.c_str(),
attribute_it->second);
}
// Recursively set children for the child.
if (!child_node.AddElements(child_element.subelements))
return false;
child_node.SetContent(child_element.content);
if (!xmlAddChild(node_.get(), child_node.GetRawPtr())) {
LOG(ERROR) << "Failed to set child " << child_element.name
<< " to parent element "
<< reinterpret_cast<const char*>(node_->name);
return false;
}
// Reaching here means the ownership of |child_node| transfered to |node_|.
// Release the pointer so that it doesn't get destructed in this scope.
ignore_result(child_node.Release());
}
return true;
}
void XmlNode::SetStringAttribute(const char* attribute_name,
const std::string& attribute) {
DCHECK(node_);
DCHECK(attribute_name);
xmlSetProp(node_.get(), BAD_CAST attribute_name, BAD_CAST attribute.c_str());
}
void XmlNode::SetIntegerAttribute(const char* attribute_name, uint64_t number) {
DCHECK(node_);
DCHECK(attribute_name);
xmlSetProp(node_.get(),
BAD_CAST attribute_name,
BAD_CAST (base::Uint64ToString(number).c_str()));
}
void XmlNode::SetFloatingPointAttribute(const char* attribute_name,
double number) {
DCHECK(node_);
DCHECK(attribute_name);
xmlSetProp(node_.get(), BAD_CAST attribute_name,
BAD_CAST(base::DoubleToString(number).c_str()));
}
void XmlNode::SetId(uint32_t id) {
SetIntegerAttribute("id", id);
}
void XmlNode::SetContent(const std::string& content) {
DCHECK(node_);
xmlNodeSetContent(node_.get(), BAD_CAST content.c_str());
}
scoped_xml_ptr<xmlNode> XmlNode::PassScopedPtr() {
DVLOG(2) << "Passing node_.";
DCHECK(node_);
return std::move(node_);
}
xmlNodePtr XmlNode::Release() {
DVLOG(2) << "Releasing node_.";
DCHECK(node_);
return node_.release();
}
xmlNodePtr XmlNode::GetRawPtr() {
return node_.get();
}
RepresentationBaseXmlNode::RepresentationBaseXmlNode(const char* name)
: XmlNode(name) {}
RepresentationBaseXmlNode::~RepresentationBaseXmlNode() {}
bool RepresentationBaseXmlNode::AddContentProtectionElements(
const std::list<ContentProtectionElement>& content_protection_elements) {
std::list<ContentProtectionElement>::const_iterator content_protection_it =
content_protection_elements.begin();
for (; content_protection_it != content_protection_elements.end();
++content_protection_it) {
if (!AddContentProtectionElement(*content_protection_it))
return false;
}
return true;
}
void RepresentationBaseXmlNode::AddSupplementalProperty(
const std::string& scheme_id_uri,
const std::string& value) {
XmlNode supplemental_property("SupplementalProperty");
supplemental_property.SetStringAttribute("schemeIdUri", scheme_id_uri);
supplemental_property.SetStringAttribute("value", value);
AddChild(supplemental_property.PassScopedPtr());
}
void RepresentationBaseXmlNode::AddEssentialProperty(
const std::string& scheme_id_uri,
const std::string& value) {
XmlNode essential_property("EssentialProperty");
essential_property.SetStringAttribute("schemeIdUri", scheme_id_uri);
essential_property.SetStringAttribute("value", value);
AddChild(essential_property.PassScopedPtr());
}
bool RepresentationBaseXmlNode::AddContentProtectionElement(
const ContentProtectionElement& content_protection_element) {
XmlNode content_protection_node("ContentProtection");
// @value is an optional attribute.
if (!content_protection_element.value.empty()) {
content_protection_node.SetStringAttribute(
"value", content_protection_element.value);
}
content_protection_node.SetStringAttribute(
"schemeIdUri", content_protection_element.scheme_id_uri);
typedef std::map<std::string, std::string> AttributesMapType;
const AttributesMapType& additional_attributes =
content_protection_element.additional_attributes;
AttributesMapType::const_iterator attributes_it =
additional_attributes.begin();
for (; attributes_it != additional_attributes.end(); ++attributes_it) {
content_protection_node.SetStringAttribute(attributes_it->first.c_str(),
attributes_it->second);
}
if (!content_protection_node.AddElements(
content_protection_element.subelements)) {
return false;
}
return AddChild(content_protection_node.PassScopedPtr());
}
AdaptationSetXmlNode::AdaptationSetXmlNode()
: RepresentationBaseXmlNode("AdaptationSet") {}
AdaptationSetXmlNode::~AdaptationSetXmlNode() {}
void AdaptationSetXmlNode::AddRoleElement(const std::string& scheme_id_uri,
const std::string& value) {
XmlNode role("Role");
role.SetStringAttribute("schemeIdUri", scheme_id_uri);
role.SetStringAttribute("value", value);
AddChild(role.PassScopedPtr());
}
RepresentationXmlNode::RepresentationXmlNode()
: RepresentationBaseXmlNode("Representation") {}
RepresentationXmlNode::~RepresentationXmlNode() {}
bool RepresentationXmlNode::AddVideoInfo(const VideoInfo& video_info,
bool set_width,
bool set_height,
bool set_frame_rate) {
if (!video_info.has_width() || !video_info.has_height()) {
LOG(ERROR) << "Missing width or height for adding a video info.";
return false;
}
if (video_info.has_pixel_width() && video_info.has_pixel_height()) {
SetStringAttribute("sar", base::IntToString(video_info.pixel_width()) +
":" +
base::IntToString(video_info.pixel_height()));
}
if (set_width)
SetIntegerAttribute("width", video_info.width());
if (set_height)
SetIntegerAttribute("height", video_info.height());
if (set_frame_rate) {
SetStringAttribute("frameRate",
base::IntToString(video_info.time_scale()) + "/" +
base::IntToString(video_info.frame_duration()));
}
if (video_info.has_playback_rate()) {
SetStringAttribute("maxPlayoutRate",
base::IntToString(video_info.playback_rate()));
// Since the trick play stream contains only key frames, there is no coding
// dependency on the main stream. Simply set the codingDependency to false.
// TODO(hmchen): propagate this attribute up to the AdaptationSet, since
// all are set to false.
SetStringAttribute("codingDependency", "false");
}
return true;
}
bool RepresentationXmlNode::AddAudioInfo(const AudioInfo& audio_info) {
if (!AddAudioChannelInfo(audio_info))
return false;
AddAudioSamplingRateInfo(audio_info);
return true;
}
bool RepresentationXmlNode::AddVODOnlyInfo(const MediaInfo& media_info) {
if (media_info.has_media_file_name()) {
XmlNode base_url("BaseURL");
base_url.SetContent(media_info.media_file_name());
if (!AddChild(base_url.PassScopedPtr()))
return false;
}
const bool need_segment_base = media_info.has_index_range() ||
media_info.has_init_range() ||
media_info.has_reference_time_scale();
if (need_segment_base) {
XmlNode segment_base("SegmentBase");
if (media_info.has_index_range()) {
segment_base.SetStringAttribute("indexRange",
RangeToString(media_info.index_range()));
}
if (media_info.has_reference_time_scale()) {
segment_base.SetIntegerAttribute("timescale",
media_info.reference_time_scale());
}
if (media_info.has_presentation_time_offset()) {
segment_base.SetIntegerAttribute("presentationTimeOffset",
media_info.presentation_time_offset());
}
if (media_info.has_init_range()) {
XmlNode initialization("Initialization");
initialization.SetStringAttribute("range",
RangeToString(media_info.init_range()));
if (!segment_base.AddChild(initialization.PassScopedPtr()))
return false;
}
if (!AddChild(segment_base.PassScopedPtr()))
return false;
}
return true;
}
bool RepresentationXmlNode::AddLiveOnlyInfo(
const MediaInfo& media_info,
const std::list<SegmentInfo>& segment_infos,
uint32_t start_number) {
XmlNode segment_template("SegmentTemplate");
if (media_info.has_reference_time_scale()) {
segment_template.SetIntegerAttribute("timescale",
media_info.reference_time_scale());
}
if (media_info.has_presentation_time_offset()) {
segment_template.SetIntegerAttribute("presentationTimeOffset",
media_info.presentation_time_offset());
}
if (media_info.has_init_segment_name()) {
// The spec does not allow '$Number$' and '$Time$' in initialization
// attribute.
// TODO(rkuroiwa, kqyang): Swap this check out with a better check. These
// templates allow formatting as well.
const std::string& init_segment_name = media_info.init_segment_name();
if (init_segment_name.find("$Number$") != std::string::npos ||
init_segment_name.find("$Time$") != std::string::npos) {
LOG(ERROR) << "$Number$ and $Time$ cannot be used for "
"SegmentTemplate@initialization";
return false;
}
segment_template.SetStringAttribute("initialization",
media_info.init_segment_name());
}
if (media_info.has_segment_template()) {
segment_template.SetStringAttribute("media", media_info.segment_template());
// TODO(rkuroiwa): Need a better check. $$Number is legitimate but not a
// template.
if (media_info.segment_template().find("$Number") != std::string::npos) {
DCHECK_GE(start_number, 1u);
segment_template.SetIntegerAttribute("startNumber", start_number);
}
}
// TODO(rkuroiwa): Find out when a live MPD doesn't require SegmentTimeline.
XmlNode segment_timeline("SegmentTimeline");
return PopulateSegmentTimeline(segment_infos, &segment_timeline) &&
segment_template.AddChild(segment_timeline.PassScopedPtr()) &&
AddChild(segment_template.PassScopedPtr());
}
bool RepresentationXmlNode::AddAudioChannelInfo(const AudioInfo& audio_info) {
std::string audio_channel_config_scheme;
std::string audio_channel_config_value;
if (audio_info.codec() == kEC3Codec) {
// Convert EC3 channel map into string of hexadecimal digits. Spec: DASH-IF
// Interoperability Points v3.0 9.2.1.2.
const uint16_t ec3_channel_map =
base::HostToNet16(audio_info.codec_specific_data().ec3_channel_map());
audio_channel_config_value =
base::HexEncode(&ec3_channel_map, sizeof(ec3_channel_map));
audio_channel_config_scheme =
"tag:dolby.com,2014:dash:audio_channel_configuration:2011";
} else {
audio_channel_config_value = base::UintToString(audio_info.num_channels());
audio_channel_config_scheme =
"urn:mpeg:dash:23003:3:audio_channel_configuration:2011";
}
XmlNode audio_channel_config("AudioChannelConfiguration");
audio_channel_config.SetStringAttribute("schemeIdUri",
audio_channel_config_scheme);
audio_channel_config.SetStringAttribute("value", audio_channel_config_value);
return AddChild(audio_channel_config.PassScopedPtr());
}
// MPD expects one number for sampling frequency, or if it is a range it should
// be space separated.
void RepresentationXmlNode::AddAudioSamplingRateInfo(
const AudioInfo& audio_info) {
if (audio_info.has_sampling_frequency())
SetIntegerAttribute("audioSamplingRate", audio_info.sampling_frequency());
}
} // namespace xml
} // namespace shaka