1 files changed, 94 insertions, 0 deletions
diff --git a/tuner/src/com/android/tv/tuner/exoplayer/audio/AudioClock.java b/tuner/src/com/android/tv/tuner/exoplayer/audio/AudioClock.java
new file mode 100644
index 00000000..13eabc3a
--- /dev/null
+++ b/tuner/src/com/android/tv/tuner/exoplayer/audio/AudioClock.java
@@ -0,0 +1,94 @@
+/*
+ * Copyright (C) 2015 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.android.tv.tuner.exoplayer.audio;
+
+import android.os.SystemClock;
+import com.android.tv.common.SoftPreconditions;
+
+/**
+ * Copy of {@link com.google.android.exoplayer.MediaClock}.
+ *
+ * <p>A simple clock for tracking the progression of media time. The clock can be started, stopped
+ * and its time can be set and retrieved. When started, this clock is based on {@link
+ * SystemClock#elapsedRealtime()}.
+ */
+/* package */ class AudioClock {
+    private boolean mStarted;
+
+    /** The media time when the clock was last set or stopped. */
+    private long mPositionUs;
+
+    /**
+     * The difference between {@link SystemClock#elapsedRealtime()} and {@link #mPositionUs} when
+     * the clock was last set or mStarted.
+     */
+    private long mDeltaUs;
+
+    private float mPlaybackSpeed = 1.0f;
+    private long mDeltaUpdatedTimeUs;
+
+    /** Starts the clock. Does nothing if the clock is already started. */
+    public void start() {
+        if (!mStarted) {
+            mStarted = true;
+            mDeltaUs = elapsedRealtimeMinus(mPositionUs);
+            mDeltaUpdatedTimeUs = SystemClock.elapsedRealtime() * 1000;
+        }
+    }
+
+    /** Stops the clock. Does nothing if the clock is already stopped. */
+    public void stop() {
+        if (mStarted) {
+            mPositionUs = elapsedRealtimeMinus(mDeltaUs);
+            mStarted = false;
+        }
+    }
+
+    /** @param timeUs The position to set in microseconds. */
+    public void setPositionUs(long timeUs) {
+        this.mPositionUs = timeUs;
+        mDeltaUs = elapsedRealtimeMinus(timeUs);
+        mDeltaUpdatedTimeUs = SystemClock.elapsedRealtime() * 1000;
+    }
+
+    /** @return The current position in microseconds. */
+    public long getPositionUs() {
+        if (!mStarted) {
+            return mPositionUs;
+        }
+        if (mPlaybackSpeed != 1.0f) {
+            long elapsedTimeFromPlaybackSpeedChanged =
+                    SystemClock.elapsedRealtime() * 1000 - mDeltaUpdatedTimeUs;
+            return elapsedRealtimeMinus(mDeltaUs)
+                    + (long) ((mPlaybackSpeed - 1.0f) * elapsedTimeFromPlaybackSpeedChanged);
+        } else {
+            return elapsedRealtimeMinus(mDeltaUs);
+        }
+    }
+
+    /** Sets playback speed. {@code speed} should be positive. */
+    public void setPlaybackSpeed(float speed) {
+        SoftPreconditions.checkState(speed > 0);
+        mDeltaUs = elapsedRealtimeMinus(getPositionUs());
+        mDeltaUpdatedTimeUs = SystemClock.elapsedRealtime() * 1000;
+        mPlaybackSpeed = speed;
+    }
+
+    private long elapsedRealtimeMinus(long toSubtractUs) {
+        return SystemClock.elapsedRealtime() * 1000 - toSubtractUs;
+    }
+}