Tracking de l'application VApp (IHM du jeu)

VApp/node_modules/mpd-parser/src/segment/segmentList.js

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+import { parseByTimeline } from './timelineTimeParser';
+import { parseByDuration } from './durationTimeParser';
+import urlTypeConverter from './urlType';
+import errors from '../errors';
+
+/**
+ * Converts a <SegmentUrl> (of type URLType from the DASH spec 5.3.9.2 Table 14)
+ * to an object that matches the output of a segment in videojs/mpd-parser
+ *
+ * @param {Object} attributes
+ *   Object containing all inherited attributes from parent elements with attribute
+ *   names as keys
+ * @param {Object} segmentUrl
+ *   <SegmentURL> node to translate into a segment object
+ * @return {Object} translated segment object
+ */
+const SegmentURLToSegmentObject = (attributes, segmentUrl) => {
+  const { baseUrl, initialization = {} } = attributes;
+
+  const initSegment = urlTypeConverter({
+    baseUrl,
+    source: initialization.sourceURL,
+    range: initialization.range
+  });
+
+  const segment = urlTypeConverter({
+    baseUrl,
+    source: segmentUrl.media,
+    range: segmentUrl.mediaRange
+  });
+
+  segment.map = initSegment;
+
+  return segment;
+};
+
+/**
+ * Generates a list of segments using information provided by the SegmentList element
+ * SegmentList (DASH SPEC Section 5.3.9.3.2) contains a set of <SegmentURL> nodes.  Each
+ * node should be translated into segment.
+ *
+ * @param {Object} attributes
+ *   Object containing all inherited attributes from parent elements with attribute
+ *   names as keys
+ * @param {Object[]|undefined} segmentTimeline
+ *        List of objects representing the attributes of each S element contained within
+ *        the SegmentTimeline element
+ * @return {Object.<Array>} list of segments
+ */
+export const segmentsFromList = (attributes, segmentTimeline) => {
+  const {
+    duration,
+    segmentUrls = [],
+    periodStart
+  } = attributes;
+
+  // Per spec (5.3.9.2.1) no way to determine segment duration OR
+  // if both SegmentTimeline and @duration are defined, it is outside of spec.
+  if ((!duration && !segmentTimeline) ||
+      (duration && segmentTimeline)) {
+    throw new Error(errors.SEGMENT_TIME_UNSPECIFIED);
+  }
+
+  const segmentUrlMap = segmentUrls.map(segmentUrlObject =>
+    SegmentURLToSegmentObject(attributes, segmentUrlObject));
+  let segmentTimeInfo;
+
+  if (duration) {
+    segmentTimeInfo = parseByDuration(attributes);
+  }
+
+  if (segmentTimeline) {
+    segmentTimeInfo = parseByTimeline(attributes, segmentTimeline);
+  }
+
+  const segments = segmentTimeInfo.map((segmentTime, index) => {
+    if (segmentUrlMap[index]) {
+      const segment = segmentUrlMap[index];
+      // See DASH spec section 5.3.9.2.2
+      // - if timescale isn't present on any level, default to 1.
+      const timescale = attributes.timescale || 1;
+      // - if presentationTimeOffset isn't present on any level, default to 0
+      const presentationTimeOffset = attributes.presentationTimeOffset || 0;
+
+      segment.timeline = segmentTime.timeline;
+      segment.duration = segmentTime.duration;
+      segment.number = segmentTime.number;
+      segment.presentationTime =
+        periodStart + ((segmentTime.time - presentationTimeOffset) / timescale);
+
+      return segment;
+    }
+    // Since we're mapping we should get rid of any blank segments (in case
+    // the given SegmentTimeline is handling for more elements than we have
+    // SegmentURLs for).
+  }).filter(segment => segment);
+
+  return segments;
+};