Merge pull request #176 from google/dev

dev -> dev-hls

library/src/main/java/com/google/android/exoplayer/SmoothFrameReleaseTimeHelper.java

+/*
+ * Copyright (C) 2014 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.android.exoplayer;
+
+import com.google.android.exoplayer.MediaCodecVideoTrackRenderer.FrameReleaseTimeHelper;
+
+import android.annotation.TargetApi;
+import android.view.Choreographer;
+import android.view.Choreographer.FrameCallback;
+
+/**
+ * Makes a best effort to adjust frame release timestamps for a smoother visual result.
+ */
+@TargetApi(16)
+public class SmoothFrameReleaseTimeHelper implements FrameReleaseTimeHelper, FrameCallback {
+
+  private static final long CHOREOGRAPHER_SAMPLE_DELAY_MILLIS = 500;
+  private static final long MAX_ALLOWED_DRIFT_NS = 20000000;
+
+  private static final long VSYNC_OFFSET_PERCENTAGE = 80;
+  private static final int MIN_FRAMES_FOR_ADJUSTMENT = 6;
+
+  private final boolean usePrimaryDisplayVsync;
+  private final long vsyncDurationNs;
+  private final long vsyncOffsetNs;
+
+  private Choreographer choreographer;
+  private long sampledVsyncTimeNs;
+
+  private long lastUnadjustedFrameTimeUs;
+  private long adjustedLastFrameTimeNs;
+  private long pendingAdjustedFrameTimeNs;
+
+  private boolean haveSync;
+  private long syncReleaseTimeNs;
+  private long syncFrameTimeNs;
+  private int frameCount;
+
+  /**
+   * @param primaryDisplayRefreshRate The refresh rate of the default display.
+   * @param usePrimaryDisplayVsync Whether to snap to the primary display vsync. May not be
+   *     suitable when rendering to secondary displays.
+   */
+  public SmoothFrameReleaseTimeHelper(
+      float primaryDisplayRefreshRate, boolean usePrimaryDisplayVsync) {
+    this.usePrimaryDisplayVsync = usePrimaryDisplayVsync;
+    if (usePrimaryDisplayVsync) {
+      vsyncDurationNs = (long) (1000000000d / primaryDisplayRefreshRate);
+      vsyncOffsetNs = (vsyncDurationNs * VSYNC_OFFSET_PERCENTAGE) / 100;
+    } else {
+      vsyncDurationNs = -1;
+      vsyncOffsetNs = -1;
+    }
+  }
+
+  @Override
+  public void enable() {
+    haveSync = false;
+    if (usePrimaryDisplayVsync) {
+      sampledVsyncTimeNs = 0;
+      choreographer = Choreographer.getInstance();
+      choreographer.postFrameCallback(this);
+    }
+  }
+
+  @Override
+  public void disable() {
+    if (usePrimaryDisplayVsync) {
+      choreographer.removeFrameCallback(this);
+      choreographer = null;
+    }
+  }
+
+  @Override
+  public void doFrame(long vsyncTimeNs) {
+    sampledVsyncTimeNs = vsyncTimeNs;
+    choreographer.postFrameCallbackDelayed(this, CHOREOGRAPHER_SAMPLE_DELAY_MILLIS);
+  }
+
+  @Override
+  public long adjustReleaseTime(long unadjustedFrameTimeUs, long unadjustedReleaseTimeNs) {
+    long unadjustedFrameTimeNs = unadjustedFrameTimeUs * 1000;
+
+    // Until we know better, the adjustment will be a no-op.
+    long adjustedFrameTimeNs = unadjustedFrameTimeNs;
+    long adjustedReleaseTimeNs = unadjustedReleaseTimeNs;
+
+    if (haveSync) {
+      // See if we've advanced to the next frame.
+      if (unadjustedFrameTimeUs != lastUnadjustedFrameTimeUs) {
+        frameCount++;
+        adjustedLastFrameTimeNs = pendingAdjustedFrameTimeNs;
+      }
+      if (frameCount >= MIN_FRAMES_FOR_ADJUSTMENT) {
+        // We're synced and have waited the required number of frames to apply an adjustment.
+        // Calculate the average frame time across all the frames we've seen since the last sync.
+        // This will typically give us a framerate at a finer granularity than the frame times
+        // themselves (which often only have millisecond granularity).
+        long averageFrameTimeNs = (unadjustedFrameTimeNs - syncFrameTimeNs) / frameCount;
+        // Project the adjusted frame time forward using the average.
+        long candidateAdjustedFrameTimeNs = adjustedLastFrameTimeNs + averageFrameTimeNs;
+
+        if (isDriftTooLarge(candidateAdjustedFrameTimeNs, unadjustedReleaseTimeNs)) {
+          haveSync = false;
+        } else {
+          adjustedFrameTimeNs = candidateAdjustedFrameTimeNs;
+          adjustedReleaseTimeNs = syncReleaseTimeNs + adjustedFrameTimeNs - syncFrameTimeNs;
+        }
+      } else {
+        // We're synced but haven't waited the required number of frames to apply an adjustment.
+        // Check drift anyway.
+        if (isDriftTooLarge(unadjustedFrameTimeNs, unadjustedReleaseTimeNs)) {
+          haveSync = false;
+        }
+      }
+    }
+
+    // If we need to sync, do so now.
+    if (!haveSync) {
+      syncFrameTimeNs = unadjustedFrameTimeNs;
+      syncReleaseTimeNs = unadjustedReleaseTimeNs;
+      frameCount = 0;
+      haveSync = true;
+      onSynced();
+    }
+
+    lastUnadjustedFrameTimeUs = unadjustedFrameTimeUs;
+    pendingAdjustedFrameTimeNs = adjustedFrameTimeNs;
+
+    if (sampledVsyncTimeNs == 0) {
+      return adjustedReleaseTimeNs;
+    }
+
+    // Find the timestamp of the closest vsync. This is the vsync that we're targeting.
+    long snappedTimeNs = closestVsync(adjustedReleaseTimeNs, sampledVsyncTimeNs, vsyncDurationNs);
+    // Apply an offset so that we release before the target vsync, but after the previous one.
+    return snappedTimeNs - vsyncOffsetNs;
+  }
+
+  protected void onSynced() {
+    // Do nothing.
+  }
+
+  private boolean isDriftTooLarge(long frameTimeNs, long releaseTimeNs) {
+    long elapsedFrameTimeNs = frameTimeNs - syncFrameTimeNs;
+    long elapsedReleaseTimeNs = releaseTimeNs - syncReleaseTimeNs;
+    return Math.abs(elapsedReleaseTimeNs - elapsedFrameTimeNs) > MAX_ALLOWED_DRIFT_NS;
+  }
+
+  private static long closestVsync(long releaseTime, long sampledVsyncTime, long vsyncDuration) {
+    long vsyncCount = (releaseTime - sampledVsyncTime) / vsyncDuration;
+    long snappedTimeNs = sampledVsyncTime + (vsyncDuration * vsyncCount);
+    long snappedBeforeNs;
+    long snappedAfterNs;
+    if (releaseTime <= snappedTimeNs) {
+      snappedBeforeNs = snappedTimeNs - vsyncDuration;
+      snappedAfterNs = snappedTimeNs;
+    } else {
+      snappedBeforeNs = snappedTimeNs;
+      snappedAfterNs = snappedTimeNs + vsyncDuration;
+    }
+    long snappedAfterDiff = snappedAfterNs - releaseTime;
+    long snappedBeforeDiff = releaseTime - snappedBeforeNs;
+    return snappedAfterDiff < snappedBeforeDiff ? snappedAfterNs : snappedBeforeNs;
+  }
+
+}

library/src/main/java/com/google/android/exoplayer/dash/mpd/SegmentBase.java

@@ -15,6 +15,8 @@
  */
 package com.google.android.exoplayer.dash.mpd;
 
+import com.google.android.exoplayer.util.Util;
+
 import android.net.Uri;
 
 import java.util.List;
@@ -155,7 +157,7 @@ public abstract class SegmentBase {
       } else {
         unscaledSegmentTime = (sequenceNumber - startNumber) * duration;
       }
-      return (unscaledSegmentTime * 1000000) / timescale;
+      return Util.scaleLargeTimestamp(unscaledSegmentTime, 1000000, timescale);
     }
 
     public abstract RangedUri getSegmentUrl(Representation representation, int index);

library/src/main/java/com/google/android/exoplayer/smoothstreaming/SmoothStreamingManifest.java

@@ -53,19 +53,8 @@ public class SmoothStreamingManifest {
     this.isLive = isLive;
     this.protectionElement = protectionElement;
     this.streamElements = streamElements;
-    if (timescale >= MICROS_PER_SECOND && (timescale % MICROS_PER_SECOND) == 0) {
-      long divisionFactor = timescale / MICROS_PER_SECOND;
-      dvrWindowLengthUs = dvrWindowLength / divisionFactor;
-      durationUs = duration / divisionFactor;
-    } else if (timescale < MICROS_PER_SECOND && (MICROS_PER_SECOND % timescale) == 0) {
-      long multiplicationFactor = MICROS_PER_SECOND / timescale;
-      dvrWindowLengthUs = dvrWindowLength * multiplicationFactor;
-      durationUs = duration * multiplicationFactor;
-    } else {
-      double multiplicationFactor = (double) MICROS_PER_SECOND / timescale;
-      dvrWindowLengthUs = (long) (dvrWindowLength * multiplicationFactor);
-      durationUs = (long) (duration * multiplicationFactor);
-    }
+    dvrWindowLengthUs = Util.scaleLargeTimestamp(dvrWindowLength, MICROS_PER_SECOND, timescale);
+    durationUs = Util.scaleLargeTimestamp(duration, MICROS_PER_SECOND, timescale);
   }
 
   /**
@@ -186,26 +175,10 @@ public class SmoothStreamingManifest {
       this.tracks = tracks;
       this.chunkCount = chunkStartTimes.size();
       this.chunkStartTimes = chunkStartTimes;
-      chunkStartTimesUs = new long[chunkStartTimes.size()];
-      if (timescale >= MICROS_PER_SECOND && (timescale % MICROS_PER_SECOND) == 0) {
-        long divisionFactor = timescale / MICROS_PER_SECOND;
-        for (int i = 0; i < chunkStartTimesUs.length; i++) {
-          chunkStartTimesUs[i] = chunkStartTimes.get(i) / divisionFactor;
-        }
-        lastChunkDurationUs = lastChunkDuration / divisionFactor;
-      } else if (timescale < MICROS_PER_SECOND && (MICROS_PER_SECOND % timescale) == 0) {
-        long multiplicationFactor = MICROS_PER_SECOND / timescale;
-        for (int i = 0; i < chunkStartTimesUs.length; i++) {
-          chunkStartTimesUs[i] = chunkStartTimes.get(i) * multiplicationFactor;
-        }
-        lastChunkDurationUs = lastChunkDuration * multiplicationFactor;
-      } else {
-        double multiplicationFactor = (double) MICROS_PER_SECOND / timescale;
-        for (int i = 0; i < chunkStartTimesUs.length; i++) {
-          chunkStartTimesUs[i] = (long) (chunkStartTimes.get(i) * multiplicationFactor);
-        }
-        lastChunkDurationUs = (long) (lastChunkDuration * multiplicationFactor);
-      }
+      lastChunkDurationUs =
+          Util.scaleLargeTimestamp(lastChunkDuration, MICROS_PER_SECOND, timescale);
+      chunkStartTimesUs =
+          Util.scaleLargeTimestamps(chunkStartTimes, MICROS_PER_SECOND, timescale);
     }
 
     /**

library/src/main/java/com/google/android/exoplayer/smoothstreaming/SmoothStreamingManifestParser.java

@@ -450,6 +450,7 @@ public class SmoothStreamingManifestParser implements ManifestParser<SmoothStrea
 
     private static final String KEY_FRAGMENT_DURATION = "d";
     private static final String KEY_FRAGMENT_START_TIME = "t";
+    private static final String KEY_FRAGMENT_REPEAT_COUNT = "r";
 
     private final Uri baseUri;
     private final List<TrackElement> tracks;
@@ -504,9 +505,18 @@ public class SmoothStreamingManifestParser implements ManifestParser<SmoothStrea
           throw new ParserException("Unable to infer start time");
         }
       }
+      chunkIndex++;
       startTimes.add(startTime);
       lastChunkDuration = parseLong(parser, KEY_FRAGMENT_DURATION, -1L);
-      chunkIndex++;
+      // Handle repeated chunks.
+      long repeatCount = parseLong(parser, KEY_FRAGMENT_REPEAT_COUNT, 1L);
+      if (repeatCount > 1 && lastChunkDuration == -1L) {
+        throw new ParserException("Repeated chunk with unspecified duration");
+      }
+      for (int i = 1; i < repeatCount; i++) {
+        chunkIndex++;
+        startTimes.add(startTime + (lastChunkDuration * i));
+      }
     }
 
     private void parseStreamElementStartTag(XmlPullParser parser) throws ParserException {

library/src/main/java/com/google/android/exoplayer/util/Util.java

@@ -55,7 +55,8 @@ public final class Util {
       + "([Zz]|((\\+|\\-)(\\d\\d):(\\d\\d)))?");
 
   private static final Pattern XS_DURATION_PATTERN =
-      Pattern.compile("^PT(([0-9]*)H)?(([0-9]*)M)?(([0-9.]*)S)?$");
+      Pattern.compile("^P(([0-9]*)Y)?(([0-9]*)M)?(([0-9]*)D)?"
+          + "(T(([0-9]*)H)?(([0-9]*)M)?(([0-9.]*)S)?)?$");
 
   private Util() {}
 
@@ -274,11 +275,19 @@ public final class Util {
   public static long parseXsDuration(String value) {
     Matcher matcher = XS_DURATION_PATTERN.matcher(value);
     if (matcher.matches()) {
-      String hours = matcher.group(2);
-      double durationSeconds = (hours != null) ? Double.parseDouble(hours) * 3600 : 0;
-      String minutes = matcher.group(4);
+      // Durations containing years and months aren't completely defined. We assume there are
+      // 30.4368 days in a month, and 365.242 days in a year.
+      String years = matcher.group(2);
+      double durationSeconds = (years != null) ? Double.parseDouble(years) * 31556908 : 0;
+      String months = matcher.group(4);
+      durationSeconds += (months != null) ? Double.parseDouble(months) * 2629739 : 0;
+      String days = matcher.group(6);
+      durationSeconds += (days != null) ? Double.parseDouble(days) * 86400 : 0;
+      String hours = matcher.group(9);
+      durationSeconds += (hours != null) ? Double.parseDouble(hours) * 3600 : 0;
+      String minutes = matcher.group(11);
       durationSeconds += (minutes != null) ? Double.parseDouble(minutes) * 60 : 0;
-      String seconds = matcher.group(6);
+      String seconds = matcher.group(13);
       durationSeconds += (seconds != null) ? Double.parseDouble(seconds) : 0;
       return (long) (durationSeconds * 1000);
     } else {
@@ -337,4 +346,57 @@ public final class Util {
     return time;
   }
 
+  /**
+   * Scales a large timestamp.
+   * <p>
+   * Logically, scaling consists of a multiplication followed by a division. The actual operations
+   * performed are designed to minimize the probability of overflow.
+   *
+   * @param timestamp The timestamp to scale.
+   * @param multiplier The multiplier.
+   * @param divisor The divisor.
+   * @return The scaled timestamp.
+   */
+  public static long scaleLargeTimestamp(long timestamp, long multiplier, long divisor) {
+    if (divisor >= multiplier && (divisor % multiplier) == 0) {
+      long divisionFactor = divisor / multiplier;
+      return timestamp / divisionFactor;
+    } else if (divisor < multiplier && (multiplier % divisor) == 0) {
+      long multiplicationFactor = multiplier / divisor;
+      return timestamp * multiplicationFactor;
+    } else {
+      double multiplicationFactor = (double) multiplier / divisor;
+      return (long) (timestamp * multiplicationFactor);
+    }
+  }
+
+  /**
+   * Applies {@link #scaleLargeTimestamp(long, long, long)} to a list of unscaled timestamps.
+   *
+   * @param timestamps The timestamps to scale.
+   * @param multiplier The multiplier.
+   * @param divisor The divisor.
+   * @return The scaled timestamps.
+   */
+  public static long[] scaleLargeTimestamps(List<Long> timestamps, long multiplier, long divisor) {
+    long[] scaledTimestamps = new long[timestamps.size()];
+    if (divisor >= multiplier && (divisor % multiplier) == 0) {
+      long divisionFactor = divisor / multiplier;
+      for (int i = 0; i < scaledTimestamps.length; i++) {
+        scaledTimestamps[i] = timestamps.get(i) / divisionFactor;
+      }
+    } else if (divisor < multiplier && (multiplier % divisor) == 0) {
+      long multiplicationFactor = multiplier / divisor;
+      for (int i = 0; i < scaledTimestamps.length; i++) {
+        scaledTimestamps[i] = timestamps.get(i) * multiplicationFactor;
+      }
+    } else {
+      double multiplicationFactor = (double) multiplier / divisor;
+      for (int i = 0; i < scaledTimestamps.length; i++) {
+        scaledTimestamps[i] = (long) (timestamps.get(i) * multiplicationFactor);
+      }
+    }
+    return scaledTimestamps;
+  }
+
 }