Helper functions for MPD builder class

Change-Id: Ice97c734903c35b1356a445daa953dd2162d30b2

mpd/base/content_protection_element.h

@@ -0,0 +1,27 @@
+// ContentProtectionElement is shared a structure that can be passed to
+// MPD generator classes to add ContentProtection element in the resulting MPD
+// file.
+// http://goo.gl/UrsSlF
+
+#ifndef MPD_BASE_CONTENT_PROTECTION_ELEMENT_H_
+#define MPD_BASE_CONTENT_PROTECTION_ELEMENT_H_
+
+#include <map>
+#include <string>
+
+namespace dash_packager {
+
+struct ContentProtectionElement {
+  std::string value;  // Will be set for 'value' attribute.
+  std::string scheme_id_uri;  // Will be set for 'schemeIdUri' attribute.
+
+  // Other attributes for this element.
+  std::map<std::string, std::string> additional_attributes;
+
+  // The elements that will be in this element.
+  std::string subelements;
+};
+
+}  // namespace dash_packager
+
+#endif  // MPD_BASE_CONTENT_PROTECTION_ELEMENT_H_

mpd/base/mpd_utils.cc

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+#include "mpd/base/mpd_utils.h"
+
+#include <set>
+
+#include "base/logging.h"
+#include "base/strings/string_number_conversions.h"
+#include "mpd/base/content_protection_element.h"
+#include "mpd/base/xml/scoped_xml_ptr.h"
+#include "third_party/libxml/src/include/libxml/tree.h"
+
+
+namespace {
+
+// Concatenate all the codecs in |repeated_stream_info|.
+template <typename RepeatedStreamInfoType>
+std::string CodecsString(const RepeatedStreamInfoType& repeated_stream_info) {
+  std::string codecs;
+  for (int i = 0; i < repeated_stream_info.size(); ++i) {
+    codecs.append(repeated_stream_info.Get(i).codec());
+    codecs.append(",");
+  }
+
+  if (!codecs.empty()) {
+    DCHECK_EQ(codecs[codecs.size() - 1], ',');
+    codecs.resize(codecs.size() - 1);  // Cut off ',' at the end.
+  }
+
+  return codecs;
+}
+
+}  // namespace
+
+namespace dash_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();
+}
+
+bool HasLiveOnlyFields(const MediaInfo& media_info) {
+  return media_info.has_init_segment_name() ||
+         media_info.has_segment_template() || media_info.has_segment_duration();
+}
+
+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_codecs;
+  if (media_info.video_info_size() > 0)
+    video_codecs = CodecsString(media_info.video_info());
+
+  std::string audio_codecs;
+  if (media_info.audio_info_size() > 0)
+    audio_codecs = CodecsString(media_info.audio_info());
+
+  if (!video_codecs.empty() && !audio_codecs.empty()) {
+    return video_codecs + "," + audio_codecs;
+  } else if (!video_codecs.empty()) {
+    return video_codecs;
+  } else if (!audio_codecs.empty()) {
+    return audio_codecs;
+  }
+
+  return "";
+}
+
+std::string SecondsToXmlDuration(uint32 seconds) {
+  return "P" + base::UintToString(seconds) + "S";
+}
+
+bool GetDurationAttribute(xmlNodePtr node, uint32* 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;
+
+  return base::StringToUint(reinterpret_cast<const char*>(duration_value.get()),
+                            duration);
+}
+
+}  // namespace dash_packager

mpd/base/mpd_utils.h

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+// Funtions used by MpdBuilder class to generate an MPD file.
+#ifndef MPD_BASE_MPD_UTILS_H_
+#define MPD_BASE_MPD_UTILS_H_
+
+#include <string>
+
+#include "base/basictypes.h"
+#include "mpd/base/media_info.pb.h"
+#include "third_party/libxml/src/include/libxml/tree.h"
+
+namespace dash_packager {
+
+class ContentProtectionElement;
+
+bool HasVODOnlyFields(const MediaInfo& media_info);
+
+bool HasLiveOnlyFields(const MediaInfo& media_info);
+
+// If |content_protection_element| has 'value' or 'schemeIdUri' set but it's
+// also in the map, then this removes them from the map.
+// |content_protection_element| cannot be NULL.
+void RemoveDuplicateAttributes(
+    ContentProtectionElement* content_protection_element);
+
+// Returns a 'codecs' string that has all the video and audio codecs joined with
+// comma.
+std::string GetCodecs(const MediaInfo& media_info);
+
+// TODO(rkuroiwa): This probably needs to change to floating point number.
+// Returns "P<seconds>S".
+std::string SecondsToXmlDuration(uint32 seconds);
+
+// Tries to get "duration" attribute from |node|. On success |duration| is set.
+bool GetDurationAttribute(xmlNodePtr node, uint32* duration);
+
+}  // namespace dash_packager
+
+#endif  // MPD_BASE_MPD_UTILS_H_