In-progress recording (IPR) support, phase 1

This change creates a new model which divides DASH streams into VOD, IPR, and live. It is possible to create manifests which do not fit into any of the three categories according to our model, so we now assert that our input fits cleanly into one of the three. Inline manifests used in our tests had to be updated to conform to the new model. All external test assets have been verified to fit into these categories. This is phase 1 of IPR support. There should be no behavior change in this CL. In phase 2, we will make various other parts of the library aware of IPR so that IPR-specific behaviors can be achieved. Issue #477 Change-Id: I395d3a0c8c9825a3cd2efde263b8493ce0920ed9
shaka-project · Aug 29, 2016 · c7e73e0 · c7e73e0
1 parent 6351183
commit c7e73e0
Show file tree

Hide file tree

Showing 10 changed files with 263 additions and 207 deletions.
diff --git a/lib/dash/dash_parser.js b/lib/dash/dash_parser.js
@@ -472,6 +472,7 @@ shaka.dash.DashParser.prototype.parseManifest_ =
       mpd, 'suggestedPresentationDelay', XmlUtils.parseDuration);
   var maxSegmentDuration = XmlUtils.parseAttr(
       mpd, 'maxSegmentDuration', XmlUtils.parseDuration);
+  var mpdType = mpd.getAttribute('type') || 'static';
 
   var presentationTimeline;
   if (this.manifest_) {
@@ -498,13 +499,15 @@ shaka.dash.DashParser.prototype.parseManifest_ =
   var duration = periodsAndDuration.duration;
   var periods = periodsAndDuration.periods;
 
+  presentationTimeline.setStatic(mpdType == 'static');
   presentationTimeline.setDuration(duration || Number.POSITIVE_INFINITY);
   presentationTimeline.setSegmentAvailabilityDuration(
       segmentAvailabilityDuration != null ?
       segmentAvailabilityDuration :
       Number.POSITIVE_INFINITY);
   // Use @maxSegmentDuration to override smaller, derived values.
   presentationTimeline.notifyMaxSegmentDuration(maxSegmentDuration || 1);
+  if (!COMPILED) presentationTimeline.assertIsValid();
 
   if (this.manifest_) {
     // This is a manifest update, so we're done.

diff --git a/lib/media/presentation_timeline.js b/lib/media/presentation_timeline.js
@@ -45,10 +45,10 @@ shaka.media.PresentationTimeline = function(
   this.presentationDelay_ = presentationDelay;
 
   /** @private {number} */
-  this.duration_ = Number.POSITIVE_INFINITY;
+  this.duration_ = Infinity;
 
   /** @private {number} */
-  this.segmentAvailabilityDuration_ = Number.POSITIVE_INFINITY;
+  this.segmentAvailabilityDuration_ = Infinity;
 
   /** @private {?number} */
   this.maxSegmentDuration_ = 1;
@@ -58,12 +58,15 @@ shaka.media.PresentationTimeline = function(
 
   /** @private {number} */
   this.clockOffset_ = 0;
+
+  /** @private {boolean} */
+  this.static_ = true;
 };
 
 
 /**
  * @return {number} The presentation's duration in seconds.
- *   POSITIVE_INFINITY indicates that the presentation continues indefinitely.
+ *   Infinity indicates that the presentation continues indefinitely.
  * @export
  */
 shaka.media.PresentationTimeline.prototype.getDuration = function() {
@@ -75,7 +78,7 @@ shaka.media.PresentationTimeline.prototype.getDuration = function() {
  * Sets the presentation's duration.
  *
  * @param {number} duration The presentation's duration in seconds.
- *   POSITIVE_INFINITY indicates that the presentation continues indefinitely.
+ *   Infinity indicates that the presentation continues indefinitely.
  * @export
  */
 shaka.media.PresentationTimeline.prototype.setDuration = function(duration) {
@@ -97,11 +100,24 @@ shaka.media.PresentationTimeline.prototype.setClockOffset = function(offset) {
 };
 
 
+/**
+ * Sets the presentation's static flag.
+ *
+ * @param {boolean} isStatic If true, the presentation is static, meaning all
+ *   segments are available at once.
+ * @export
+ */
+shaka.media.PresentationTimeline.prototype.setStatic = function(isStatic) {
+  // NOTE: the argument name is not "static" because that's a keyword in ES6
+  this.static_ = isStatic;
+};
+
+
 /**
  * Gets the presentation's segment availability duration, which is the amount
  * of time, in seconds, that the start of a segment remains available after the
- * live-edge moves past the end of that segment. POSITIVE_INFINITY indicates
- * that segments remain available indefinitely. For example, if your live
+ * live-edge moves past the end of that segment. Infinity indicates that
+ * segments remain available indefinitely. For example, if your live
  * presentation has a 5 minute DVR window and your segments are 10 seconds long
  * then the segment availability duration should be 4 minutes and 50 seconds.
  *
@@ -186,8 +202,19 @@ shaka.media.PresentationTimeline.prototype.notifyMaxSegmentDuration = function(
  * @export
  */
 shaka.media.PresentationTimeline.prototype.isLive = function() {
-  return this.duration_ == Number.POSITIVE_INFINITY ||
-         this.segmentAvailabilityDuration_ < Number.POSITIVE_INFINITY;
+  return this.duration_ == Infinity &&
+         !this.static_;
+};
+
+
+/**
+ * @return {boolean} True if the presentation is in progress (meaning not live,
+ *   but also not completely available); otherwise, return false.
+ * @export
+ */
+shaka.media.PresentationTimeline.prototype.isInProgress = function() {
+  return this.duration_ != Infinity &&
+         !this.static_;
 };
 
 
@@ -219,7 +246,7 @@ shaka.media.PresentationTimeline.prototype.getEarliestStart = function() {
  */
 shaka.media.PresentationTimeline.prototype.getSegmentAvailabilityStart =
     function() {
-  if (this.segmentAvailabilityDuration_ == Number.POSITIVE_INFINITY)
+  if (this.segmentAvailabilityDuration_ == Infinity)
     return 0;
 
   var start = this.getSegmentAvailabilityEnd() -
@@ -239,7 +266,7 @@ shaka.media.PresentationTimeline.prototype.getSegmentAvailabilityStart =
  */
 shaka.media.PresentationTimeline.prototype.getSegmentAvailabilityEnd =
     function() {
-  if (this.presentationStartTime_ == null || !this.isLive())
+  if (!this.isLive())
     return this.duration_;
 
   return Math.min(this.getLiveEdge_(), this.duration_);
@@ -270,3 +297,30 @@ shaka.media.PresentationTimeline.prototype.getLiveEdge_ = function() {
       0, now - this.maxSegmentDuration_ - this.presentationStartTime_);
 };
 
+
+if (!COMPILED) {
+  /**
+   * Debug only: assert that the timeline parameters make sense for the type of
+   *   presentation (VOD, IPR, live).
+   */
+  shaka.media.PresentationTimeline.prototype.assertIsValid = function() {
+    if (this.isLive()) {
+      // Implied by isLive(): infinite and dynamic.
+      // Live streams should have a start time.
+      goog.asserts.assert(this.presentationStartTime_ != null,
+          'Detected as live stream, but does not match our model of live!');
+    } else if (this.isInProgress()) {
+      // Implied by isInProgress(): finite and dynamic.
+      // IPR segments should not expire.
+      goog.asserts.assert(this.segmentAvailabilityDuration_ == Infinity,
+          'Detected as IPR stream, but does not match our model of IPR!');
+    } else {  // VOD
+      // VOD segments should not expire and the presentation should be finite
+      // and static.
+      goog.asserts.assert(this.segmentAvailabilityDuration_ == Infinity &&
+                          this.duration_ != Infinity &&
+                          this.static_,
+          'Detected as VOD stream, but does not match our model of VOD!');
+    }
+  };
+}
diff --git a/lib/player.js b/lib/player.js
@@ -668,8 +668,7 @@ shaka.Player.prototype.getManifestUri = function() {
 
 
 /**
- * @return {boolean} True if the current stream is live.  False if the stream is
- *     VOD or if there is no active stream.
+ * @return {boolean} True if the current stream is live.  False otherwise.
  * @export
  */
 shaka.Player.prototype.isLive = function() {
@@ -679,6 +678,18 @@ shaka.Player.prototype.isLive = function() {
 };
 
 
+/**
+ * @return {boolean} True if the current stream is in-progress VOD.
+ *   False otherwise.
+ * @export
+ */
+shaka.Player.prototype.isInProgress = function() {
+  return this.manifest_ ?
+         this.manifest_.presentationTimeline.isInProgress() :
+         false;
+};
+
+
 /**
  * Get the seekable range for the current stream.
  * @return {{start: number, end: number}}

diff --git a/test/dash/dash_parser_live_unit.js b/test/dash/dash_parser_live_unit.js
@@ -70,14 +70,15 @@ describe('DashParser.Live', function() {
    * Makes a simple live manifest with the given representation contents.
    *
    * @param {!Array.<string>} lines
-   * @param {number} updatePeriod
+   * @param {number} updateTime
    * @param {number=} opt_duration
    * @return {string}
    */
-  function makeSimpleLiveManifestText(lines, updatePeriod, opt_duration) {
+  function makeSimpleLiveManifestText(lines, updateTime, opt_duration) {
     var attr = opt_duration ? 'duration="PT' + opt_duration + 'S"' : '';
     var template = [
-      '<MPD type="dynamic" minimumUpdatePeriod="PT%(updatePeriod)dS">',
+      '<MPD type="dynamic" minimumUpdatePeriod="PT%(updateTime)dS"',
+      '    availabilityStartTime="1970-01-01T00:00:00Z">',
       '  <Period id="1" %(attr)s>',
       '    <AdaptationSet mimeType="video/mp4">',
       '      <Representation id="3" bandwidth="500">',
@@ -91,7 +92,7 @@ describe('DashParser.Live', function() {
     var text = sprintf(template, {
       attr: attr,
       contents: lines.join('\n'),
-      updatePeriod: updatePeriod
+      updateTime: updateTime
     });
     return text;
   }
@@ -319,7 +320,8 @@ describe('DashParser.Live', function() {
       '<SegmentTemplate startNumber="1" media="s$Number$.mp4" duration="2" />'
     ];
     var template = [
-      '<MPD type="dynamic" minimumUpdatePeriod="PT%(updateTime)dS">',
+      '<MPD type="dynamic" availabilityStartTime="1970-01-01T00:00:00Z"',
+      '    minimumUpdatePeriod="PT%(updateTime)dS">',
       '  <Period id="4">',
       '    <AdaptationSet mimeType="video/mp4">',
       '      <Representation id="6" bandwidth="500">',
@@ -352,7 +354,8 @@ describe('DashParser.Live', function() {
 
   it('uses redirect URL for manifest BaseURL', function(done) {
     var template = [
-      '<MPD type="dynamic" minimumUpdatePeriod="PT%(updatePeriod)dS">',
+      '<MPD type="dynamic" availabilityStartTime="1970-01-01T00:00:00Z"',
+      '    minimumUpdatePeriod="PT%(updateTime)dS">',
       '  <Period id="1" duration="PT30S">',
       '    <AdaptationSet mimeType="video/mp4">',
       '      <Representation id="3" bandwidth="500">',
@@ -368,7 +371,7 @@ describe('DashParser.Live', function() {
       '  </Period>',
       '</MPD>'
     ].join('\n');
-    var manifestText = sprintf(template, {updatePeriod: updateTime});
+    var manifestText = sprintf(template, {updateTime: updateTime});
     var manifestData = shaka.util.StringUtils.toUTF8(manifestText);
     var originalUri = 'http://example.com/';
     var redirectedUri = 'http://redirected.com/';
@@ -447,7 +450,8 @@ describe('DashParser.Live', function() {
 
   it('uses Mpd.Location', function(done) {
     var manifest = [
-      '<MPD type="dynamic" minimumUpdatePeriod="PT' + updateTime + 'S">',
+      '<MPD type="dynamic" availabilityStartTime="1970-01-01T00:00:00Z"',
+      '    minimumUpdatePeriod="PT' + updateTime + 'S">',
       '  <Location>http://foobar</Location>',
       '  <Location>http://foobar2</Location>',
       '  <Period id="1" duration="PT10S">',
@@ -648,7 +652,8 @@ describe('DashParser.Live', function() {
 
     beforeEach(function() {
       var manifest = [
-        '<MPD type="dynamic" minimumUpdatePeriod="PT' + updateTime + 'S">',
+        '<MPD type="dynamic" availabilityStartTime="1970-01-01T00:00:00Z"',
+        '    minimumUpdatePeriod="PT' + updateTime + 'S">',
         '  <UTCTiming schemeIdUri="urn:mpeg:dash:utc:http-xsdate:2014"',
         '      value="http://foo.bar/date" />',
         '  <UTCTiming schemeIdUri="urn:mpeg:dash:utc:http-xsdate:2014"',

diff --git a/test/dash/dash_parser_manifest_unit.js b/test/dash/dash_parser_manifest_unit.js
@@ -304,7 +304,7 @@ describe('DashParser.Manifest', function() {
       '    </AdaptationSet>'
     ].join('\n');
     var template = [
-      '<MPD minBufferTime="PT75S">',
+      '<MPD mediaPresentationDuration="PT75S">',
       '  <Period id="1">',
       '%(periodContents)s',
       '  </Period>',
@@ -483,12 +483,12 @@ describe('DashParser.Manifest', function() {
     function makeManifest(lines) {
       var template = [
         '<MPD type="dynamic"',
-        '      availabilityStartTime="1970-01-01T00:00:00Z"',
-        '      timeShiftBufferDepth="PT60S"',
-        '      maxSegmentDuration="PT5S"',
-        '      suggestedPresentationDelay="PT0S">',
+        '     availabilityStartTime="1970-01-01T00:00:00Z"',
+        '     timeShiftBufferDepth="PT60S"',
+        '     maxSegmentDuration="PT5S"',
+        '     suggestedPresentationDelay="PT0S">',
         '  %s',
-        '  <Period duration="PT30M">',
+        '  <Period>',
         '    <AdaptationSet mimeType="video/mp4">',
         '      <Representation bandwidth="500">',
         '        <BaseURL>http://example.com</BaseURL>',

diff --git a/test/dash/dash_parser_segment_base_unit.js b/test/dash/dash_parser_segment_base_unit.js
@@ -32,7 +32,7 @@ describe('DashParser.SegmentBase', function() {
 
   it('requests init data for WebM', function(done) {
     var source = [
-      '<MPD>',
+      '<MPD mediaPresentationDuration="PT75S">',
       '  <Period>',
       '    <AdaptationSet mimeType="video/webm">',
       '      <Representation>',
@@ -68,7 +68,7 @@ describe('DashParser.SegmentBase', function() {
 
   it('inherits from Period', function(done) {
     var source = [
-      '<MPD>',
+      '<MPD mediaPresentationDuration="PT75S">',
       '  <Period>',
       '    <BaseURL>http://example.com</BaseURL>',
       '    <SegmentBase indexRange="100-200" timescale="9000">',
@@ -100,7 +100,7 @@ describe('DashParser.SegmentBase', function() {
 
   it('inherits from AdaptationSet', function(done) {
     var source = [
-      '<MPD>',
+      '<MPD mediaPresentationDuration="PT75S">',
       '  <Period>',
       '    <AdaptationSet mimeType="video/mp4">',
       '      <BaseURL>http://example.com</BaseURL>',
@@ -132,7 +132,7 @@ describe('DashParser.SegmentBase', function() {
 
   it('does not require sourceURL in Initialization', function(done) {
     var source = [
-      '<MPD>',
+      '<MPD mediaPresentationDuration="PT75S">',
       '  <Period>',
       '    <AdaptationSet mimeType="video/mp4">',
       '      <Representation>',
@@ -166,7 +166,7 @@ describe('DashParser.SegmentBase', function() {
 
   it('merges across levels', function(done) {
     var source = [
-      '<MPD>',
+      '<MPD mediaPresentationDuration="PT75S">',
       '  <Period>',
       '    <BaseURL>http://example.com</BaseURL>',
       '    <SegmentBase timescale="9000">',
@@ -206,7 +206,7 @@ describe('DashParser.SegmentBase', function() {
 
   it('merges and overrides across levels', function(done) {
     var source = [
-      '<MPD>',
+      '<MPD mediaPresentationDuration="PT75S">',
       '  <Period>',
       '    <BaseURL>http://example.com</BaseURL>',
       '    <SegmentBase indexRange="0-10" timescale="9000">',
@@ -244,7 +244,7 @@ describe('DashParser.SegmentBase', function() {
   describe('fails for', function() {
     it('unsupported container', function(done) {
       var source = [
-        '<MPD>',
+        '<MPD mediaPresentationDuration="PT75S">',
         '  <Period>',
         '    <BaseURL>http://example.com</BaseURL>',
         '    <AdaptationSet mimeType="video/cat">',
@@ -263,7 +263,7 @@ describe('DashParser.SegmentBase', function() {
 
     it('missing init segment for WebM', function(done) {
       var source = [
-        '<MPD>',
+        '<MPD mediaPresentationDuration="PT75S">',
         '  <Period>',
         '    <BaseURL>http://example.com</BaseURL>',
         '    <AdaptationSet mimeType="video/webm">',
@@ -282,7 +282,7 @@ describe('DashParser.SegmentBase', function() {
 
     it('no @indexRange nor RepresentationIndex', function(done) {
       var source = [
-        '<MPD>',
+        '<MPD mediaPresentationDuration="PT75S">',
         '  <Period>',
         '    <BaseURL>http://example.com</BaseURL>',
         '    <AdaptationSet mimeType="video/webm">',