shaka-packager/packager/mpd/base/mpd_utils.cc

265 lines
9.0 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/mpd_utils.h"
#include <libxml/tree.h>
#include "packager/base/logging.h"
#include "packager/base/strings/string_number_conversions.h"
#include "packager/mpd/base/xml/scoped_xml_ptr.h"
namespace edash_packager {
bool HasVODOnlyFields(const MediaInfo& media_info) {
return media_info.has_init_range() || media_info.has_index_range() ||
media_info.has_media_file_name() ||
media_info.has_media_duration_seconds();
}
bool HasLiveOnlyFields(const MediaInfo& media_info) {
return media_info.has_init_segment_name() ||
media_info.has_segment_template() ||
media_info.has_segment_duration_seconds();
}
void RemoveDuplicateAttributes(
ContentProtectionElement* content_protection_element) {
DCHECK(content_protection_element);
typedef std::map<std::string, std::string> AttributesMap;
AttributesMap& attributes = content_protection_element->additional_attributes;
if (!content_protection_element->value.empty())
attributes.erase("value");
if (!content_protection_element->scheme_id_uri.empty())
attributes.erase("schemeIdUri");
}
std::string GetCodecs(const MediaInfo& media_info) {
std::string video_codec;
if (media_info.has_video_info())
video_codec = media_info.video_info().codec();
std::string audio_codec;
if (media_info.has_audio_info())
audio_codec = media_info.audio_info().codec();
if (!video_codec.empty() && !audio_codec.empty()) {
return video_codec + "," + audio_codec;
} else if (!video_codec.empty()) {
return video_codec;
} else if (!audio_codec.empty()) {
return audio_codec;
}
return "";
}
std::string SecondsToXmlDuration(double seconds) {
return "PT" + base::DoubleToString(seconds) + "S";
}
bool GetDurationAttribute(xmlNodePtr node, float* duration) {
DCHECK(node);
DCHECK(duration);
static const char kDuration[] = "duration";
xml::ScopedXmlPtr<xmlChar>::type duration_value(
xmlGetProp(node, BAD_CAST kDuration));
if (!duration_value)
return false;
double duration_double_precision = 0.0;
if (!base::StringToDouble(reinterpret_cast<const char*>(duration_value.get()),
&duration_double_precision)) {
return false;
}
*duration = static_cast<float>(duration_double_precision);
return true;
}
bool MoreThanOneTrue(bool b1, bool b2, bool b3) {
return (b1 && b2) || (b2 && b3) || (b3 && b1);
}
bool AtLeastOneTrue(bool b1, bool b2, bool b3) { return b1 || b2 || b3; }
bool OnlyOneTrue(bool b1, bool b2, bool b3) {
return !MoreThanOneTrue(b1, b2, b3) && AtLeastOneTrue(b1, b2, b3);
}
// Coverts binary data into human readable UUID format.
bool HexToUUID(const std::string& data, std::string* uuid_format) {
DCHECK(uuid_format);
const size_t kExpectedUUIDSize = 16;
if (data.size() != kExpectedUUIDSize) {
LOG(ERROR) << "UUID size is expected to be " << kExpectedUUIDSize
<< " but is " << data.size() << " and the data in hex is "
<< base::HexEncode(data.data(), data.size());
return false;
}
const std::string hex_encoded =
base::StringToLowerASCII(base::HexEncode(data.data(), data.size()));
DCHECK_EQ(hex_encoded.size(), kExpectedUUIDSize * 2);
base::StringPiece all(hex_encoded);
// Note UUID has 5 parts separated with dashes.
// e.g. 123e4567-e89b-12d3-a456-426655440000
// These StringPieces have each part.
base::StringPiece first = all.substr(0, 8);
base::StringPiece second = all.substr(8, 4);
base::StringPiece third = all.substr(12, 4);
base::StringPiece fourth = all.substr(16, 4);
base::StringPiece fifth = all.substr(20, 12);
// 32 hexadecimal characters with 4 hyphens.
const size_t kHumanReadableUUIDSize = 36;
uuid_format->reserve(kHumanReadableUUIDSize);
first.CopyToString(uuid_format);
uuid_format->append("-");
second.AppendToString(uuid_format);
uuid_format->append("-");
third.AppendToString(uuid_format);
uuid_format->append("-");
fourth.AppendToString(uuid_format);
uuid_format->append("-");
fifth.AppendToString(uuid_format);
return true;
}
void UpdateContentProtectionPsshHelper(
const std::string& drm_uuid,
const std::string& pssh,
std::list<ContentProtectionElement>* content_protection_elements) {
const std::string drm_uuid_schemd_id_uri_form = "urn:uuid:" + drm_uuid;
for (std::list<ContentProtectionElement>::iterator protection =
content_protection_elements->begin();
protection != content_protection_elements->end(); ++protection) {
if (protection->scheme_id_uri != drm_uuid_schemd_id_uri_form) {
continue;
}
for (std::vector<Element>::iterator subelement =
protection->subelements.begin();
subelement != protection->subelements.end(); ++subelement) {
if (subelement->name == kPsshElementName) {
// For now, we want to remove the PSSH element because some players do
// not support updating pssh.
protection->subelements.erase(subelement);
// TODO(rkuroiwa): Uncomment this and remove the line above when
// shaka-player supports updating PSSH.
// subelement->content = pssh;
return;
}
}
// Reaching here means <cenc:pssh> does not exist under the
// ContentProtection element. Add it.
// TODO(rkuroiwa): Uncomment this when shaka-player supports updating PSSH.
// Element cenc_pssh;
// cenc_pssh.name = kPsshElementName;
// cenc_pssh.content = pssh;
// protection->subelements.push_back(cenc_pssh);
return;
}
// Reaching here means that ContentProtection for the DRM does not exist.
// Add it.
ContentProtectionElement content_protection;
content_protection.scheme_id_uri = drm_uuid_schemd_id_uri_form;
// TODO(rkuroiwa): Uncomment this when shaka-player supports updating PSSH.
// Element cenc_pssh;
// cenc_pssh.name = kPsshElementName;
// cenc_pssh.content = pssh;
// content_protection.subelements.push_back(cenc_pssh);
content_protection_elements->push_back(content_protection);
return;
}
namespace {
// Helper function. This works because Representation and AdaptationSet both
// have AddContentProtectionElement().
template <typename ContentProtectionParent>
void AddContentProtectionElementsHelperTemplated(
const MediaInfo& media_info,
ContentProtectionParent* parent) {
DCHECK(parent);
if (!media_info.has_protected_content())
return;
const MediaInfo::ProtectedContent& protected_content =
media_info.protected_content();
// DASH MPD spec specifies a default ContentProtection element for ISO BMFF
// (MP4) files.
const bool is_mp4_container =
media_info.container_type() == MediaInfo::CONTAINER_MP4;
if (is_mp4_container) {
ContentProtectionElement mp4_content_protection;
mp4_content_protection.scheme_id_uri = kEncryptedMp4Scheme;
mp4_content_protection.value = kEncryptedMp4Value;
if (protected_content.has_default_key_id()) {
std::string key_id_uuid_format;
if (HexToUUID(protected_content.default_key_id(), &key_id_uuid_format)) {
mp4_content_protection.additional_attributes["cenc:default_KID"] =
key_id_uuid_format;
} else {
LOG(ERROR) << "Failed to convert default key ID into UUID format.";
}
}
parent->AddContentProtectionElement(mp4_content_protection);
}
for (int i = 0; i < protected_content.content_protection_entry().size();
++i) {
const MediaInfo::ProtectedContent::ContentProtectionEntry& entry =
protected_content.content_protection_entry(i);
if (!entry.has_uuid()) {
LOG(WARNING)
<< "ContentProtectionEntry was specified but no UUID is set for "
<< entry.name_version() << ", skipping.";
continue;
}
ContentProtectionElement drm_content_protection;
drm_content_protection.scheme_id_uri = "urn:uuid:" + entry.uuid();
if (entry.has_name_version())
drm_content_protection.value = entry.name_version();
if (entry.has_pssh()) {
std::string base64_encoded_pssh;
base::Base64Encode(entry.pssh(), &base64_encoded_pssh);
Element cenc_pssh;
cenc_pssh.name = kPsshElementName;
cenc_pssh.content = base64_encoded_pssh;
drm_content_protection.subelements.push_back(cenc_pssh);
}
parent->AddContentProtectionElement(drm_content_protection);
}
LOG_IF(WARNING, protected_content.content_protection_entry().size() == 0)
<< "The media is encrypted but no content protection specified.";
}
} // namespace
void AddContentProtectionElements(const MediaInfo& media_info,
Representation* parent) {
AddContentProtectionElementsHelperTemplated(media_info, parent);
}
void AddContentProtectionElements(const MediaInfo& media_info,
AdaptationSet* parent) {
AddContentProtectionElementsHelperTemplated(media_info, parent);
}
} // namespace edash_packager