Adds support for adjustable playback speed

ExoPlayer was updated to 2.4.2, which supports playback speed change.

A speed selector was also added in the MainPlayer and PlayerPopup.

Fixes #153.

app/build.gradle

@@ -50,5 +50,5 @@ dependencies {
     compile 'de.hdodenhof:circleimageview:2.0.0'
     compile 'com.github.nirhart:parallaxscroll:1.0'
     compile 'com.nononsenseapps:filepicker:3.0.0'
-    compile 'com.google.android.exoplayer:exoplayer:r2.3.1'
+    compile 'com.google.android.exoplayer:exoplayer:r2.4.2'
 }

app/src/main/java/org/schabi/newpipe/player/BasePlayer.java

@@ -22,6 +22,7 @@ import com.google.android.exoplayer2.DefaultLoadControl;
 import com.google.android.exoplayer2.ExoPlaybackException;
 import com.google.android.exoplayer2.ExoPlayer;
 import com.google.android.exoplayer2.ExoPlayerFactory;
+import com.google.android.exoplayer2.PlaybackParameters;
 import com.google.android.exoplayer2.SimpleExoPlayer;
 import com.google.android.exoplayer2.Timeline;
 import com.google.android.exoplayer2.extractor.DefaultExtractorsFactory;
@@ -47,6 +48,8 @@ import com.nostra13.universalimageloader.core.ImageLoader;
 import com.nostra13.universalimageloader.core.listener.SimpleImageLoadingListener;
 
 import java.io.File;
+import java.text.DecimalFormat;
+import java.text.NumberFormat;
 import java.util.Formatter;
 import java.util.Locale;
 import java.util.concurrent.atomic.AtomicBoolean;
@@ -77,6 +80,7 @@ public abstract class BasePlayer implements ExoPlayer.EventListener, AudioManage
     public static final String VIDEO_THUMBNAIL_URL = "video_thumbnail_url";
     public static final String START_POSITION = "start_position";
     public static final String CHANNEL_NAME = "channel_name";
+    public static final String PLAYBACK_SPEED = "playback_speed";
 
     protected Bitmap videoThumbnail = null;
     protected String videoUrl = "";
@@ -176,6 +180,7 @@ public abstract class BasePlayer implements ExoPlayer.EventListener, AudioManage
         videoThumbnailUrl = intent.getStringExtra(VIDEO_THUMBNAIL_URL);
         videoStartPos = intent.getIntExtra(START_POSITION, -1);
         channelName = intent.getStringExtra(CHANNEL_NAME);
+        setPlaybackSpeed(intent.getFloatExtra(PLAYBACK_SPEED, getPlaybackSpeed()));
 
         initThumbnail();
         //play(getSelectedVideoStream(), true);
@@ -438,6 +443,10 @@ public abstract class BasePlayer implements ExoPlayer.EventListener, AudioManage
     public void onTracksChanged(TrackGroupArray trackGroups, TrackSelectionArray trackSelections) {
     }
 
+    @Override
+    public void onPlaybackParametersChanged(PlaybackParameters playbackParameters) {
+    }
+
     @Override
     public void onLoadingChanged(boolean isLoading) {
         if (DEBUG) Log.d(TAG, "onLoadingChanged() called with: isLoading = [" + isLoading + "]");
@@ -556,6 +565,7 @@ public abstract class BasePlayer implements ExoPlayer.EventListener, AudioManage
 
     private final StringBuilder stringBuilder = new StringBuilder();
     private final Formatter formatter = new Formatter(stringBuilder, Locale.getDefault());
+    private final NumberFormat speedFormatter = new DecimalFormat("0.##x");
 
     public String getTimeString(int milliSeconds) {
         long seconds = (milliSeconds % 60000L) / 1000L;
@@ -569,6 +579,10 @@ public abstract class BasePlayer implements ExoPlayer.EventListener, AudioManage
                 : formatter.format("%02d:%02d", minutes, seconds).toString();
     }
 
+    protected String formatSpeed(float speed) {
+        return speedFormatter.format(speed);
+    }
+
     protected void startProgressLoop() {
         progressLoop.removeCallbacksAndMessages(null);
         isProgressLoopRunning.set(true);
@@ -714,4 +728,12 @@ public abstract class BasePlayer implements ExoPlayer.EventListener, AudioManage
     public void setVideoThumbnailUrl(String videoThumbnailUrl) {
         this.videoThumbnailUrl = videoThumbnailUrl;
     }
+
+    public float getPlaybackSpeed() {
+        return simpleExoPlayer.getPlaybackParameters().speed;
+    }
+
+    public void setPlaybackSpeed(float speed) {
+        simpleExoPlayer.setPlaybackParameters(new PlaybackParameters(speed, 1f));
+    }
 }

app/src/main/java/org/schabi/newpipe/player/VideoPlayer.java

@@ -74,6 +74,7 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
     //////////////////////////////////////////////////////////////////////////*/
 
     public static final int DEFAULT_CONTROLS_HIDE_TIME = 3000;  // 3 Seconds
+    private static final float[] PLAYBACK_SPEEDS = {0.5f, 0.75f, 1f, 1.25f, 1.5f, 1.75f, 2f};
 
     private boolean startedFromNewPipe = true;
     private boolean wasPlaying = false;
@@ -99,6 +100,7 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
     private SeekBar playbackSeekBar;
     private TextView playbackCurrentTime;
     private TextView playbackEndTime;
+    private TextView playbackSpeed;
 
     private View topControlsRoot;
     private TextView qualityTextView;
@@ -112,6 +114,9 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
     private int qualityPopupMenuGroupId = 69;
     private PopupMenu qualityPopupMenu;
 
+    private int playbackSpeedPopupMenuGroupId = 79;
+    private PopupMenu playbackSpeedPopupMenu;
+
     ///////////////////////////////////////////////////////////////////////////
 
     public VideoPlayer(String debugTag, Context context) {
@@ -138,6 +143,7 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
         this.playbackSeekBar = (SeekBar) rootView.findViewById(R.id.playbackSeekBar);
         this.playbackCurrentTime = (TextView) rootView.findViewById(R.id.playbackCurrentTime);
         this.playbackEndTime = (TextView) rootView.findViewById(R.id.playbackEndTime);
+        this.playbackSpeed = (TextView) rootView.findViewById(R.id.playbackSpeed);
         this.bottomControlsRoot = rootView.findViewById(R.id.bottomControls);
         this.topControlsRoot = rootView.findViewById(R.id.topControls);
         this.qualityTextView = (TextView) rootView.findViewById(R.id.qualityTextView);
@@ -149,6 +155,7 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
         this.playbackSeekBar.getProgressDrawable().setColorFilter(Color.RED, PorterDuff.Mode.MULTIPLY);
 
         this.qualityPopupMenu = new PopupMenu(context, qualityTextView);
+        this.playbackSpeedPopupMenu = new PopupMenu(context, playbackSpeed);
 
         ((ProgressBar) this.loadingPanel.findViewById(R.id.progressBarLoadingPanel)).getIndeterminateDrawable().setColorFilter(Color.WHITE, PorterDuff.Mode.MULTIPLY);
 
@@ -158,6 +165,7 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
     public void initListeners() {
         super.initListeners();
         playbackSeekBar.setOnSeekBarChangeListener(this);
+        playbackSpeed.setOnClickListener(this);
         fullScreenButton.setOnClickListener(this);
         qualityTextView.setOnClickListener(this);
     }
@@ -208,6 +216,9 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
         qualityPopupMenu.getMenu().removeGroup(qualityPopupMenuGroupId);
         buildQualityMenu(qualityPopupMenu);
 
+        playbackSpeedPopupMenu.getMenu().removeGroup(playbackSpeedPopupMenuGroupId);
+        buildPlaybackSpeedMenu(playbackSpeedPopupMenu);
+
         super.playUrl(url, format, autoPlay);
     }
 
@@ -230,6 +241,15 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
         popupMenu.setOnDismissListener(this);
     }
 
+    private void buildPlaybackSpeedMenu(PopupMenu popupMenu) {
+        for (int i = 0; i < PLAYBACK_SPEEDS.length; i++) {
+            popupMenu.getMenu().add(playbackSpeedPopupMenuGroupId, i, Menu.NONE, formatSpeed(PLAYBACK_SPEEDS[i]));
+        }
+        playbackSpeed.setText(formatSpeed(getPlaybackSpeed()));
+        popupMenu.setOnMenuItemClickListener(this);
+        popupMenu.setOnDismissListener(this);
+    }
+
     /*//////////////////////////////////////////////////////////////////////////
     // States Implementation
     //////////////////////////////////////////////////////////////////////////*/
@@ -346,6 +366,7 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
 
         playbackSeekBar.setMax((int) simpleExoPlayer.getDuration());
         playbackEndTime.setText(getTimeString((int) simpleExoPlayer.getDuration()));
+        playbackSpeed.setText(formatSpeed(getPlaybackSpeed()));
 
         super.onPrepared(playWhenReady);
     }
@@ -412,15 +433,19 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
             onFullScreenButtonClicked();
         } else if (v.getId() == qualityTextView.getId()) {
             onQualitySelectorClicked();
+        } else if (v.getId() == playbackSpeed.getId()) {
+            onPlaybackSpeedClicked();
         }
     }
 
     /**
-     * Called when an item of the quality selector is selected
+     * Called when an item of the quality selector or the playback speed selector is selected
      */
     @Override
     public boolean onMenuItemClick(MenuItem menuItem) {
         if (DEBUG) Log.d(TAG, "onMenuItemClick() called with: menuItem = [" + menuItem + "], menuItem.getItemId = [" + menuItem.getItemId() + "]");
+
+        if (qualityPopupMenuGroupId == menuItem.getGroupId()) {
             if (selectedIndexStream == menuItem.getItemId()) return true;
             setVideoStartPos((int) simpleExoPlayer.getCurrentPosition());
 
@@ -430,6 +455,15 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
 
             qualityTextView.setText(menuItem.getTitle());
             return true;
+        } else if (playbackSpeedPopupMenuGroupId == menuItem.getGroupId()) {
+            int speedIndex = menuItem.getItemId();
+            float speed = PLAYBACK_SPEEDS[speedIndex];
+
+            setPlaybackSpeed(speed);
+            playbackSpeed.setText(formatSpeed(speed));
+        }
+
+        return false;
     }
 
     /**
@@ -453,6 +487,11 @@ public abstract class VideoPlayer extends BasePlayer implements SimpleExoPlayer.
         wasPlaying = isPlaying();
     }
 
+    private void onPlaybackSpeedClicked() {
+        if (DEBUG) Log.d(TAG, "onPlaybackSpeedClicked() called");
+        playbackSpeedPopupMenu.show();
+    }
+
     /*//////////////////////////////////////////////////////////////////////////
     // SeekBar Listener
     //////////////////////////////////////////////////////////////////////////*/

app/src/main/java/org/schabi/newpipe/util/NavigationHelper.java

@@ -51,7 +51,8 @@ public class NavigationHelper {
                 .putExtra(VideoPlayer.INDEX_SEL_VIDEO_STREAM, instance.getSelectedStreamIndex())
                 .putExtra(VideoPlayer.VIDEO_STREAMS_LIST, instance.getVideoStreamsList())
                 .putExtra(VideoPlayer.VIDEO_ONLY_AUDIO_STREAM, instance.getAudioStream())
-                .putExtra(BasePlayer.START_POSITION, ((int) instance.getPlayer().getCurrentPosition()));
+                .putExtra(BasePlayer.START_POSITION, ((int) instance.getPlayer().getCurrentPosition()))
+                .putExtra(BasePlayer.PLAYBACK_SPEED, instance.getPlaybackSpeed());
     }
 
     public static Intent getOpenBackgroundPlayerIntent(Context context, StreamInfo info) {

app/src/main/res/layout/activity_main_player.xml

@@ -107,7 +107,7 @@
                     android:layout_height="35dp"
                     android:layout_marginLeft="2dp"
                     android:layout_marginRight="2dp"
-                    android:layout_toLeftOf="@+id/screenRotationButton"
+                    android:layout_toLeftOf="@+id/playbackSpeed"
                     android:gravity="center"
                     android:minWidth="50dp"
                     android:text="720p"
@@ -115,6 +115,20 @@
                     android:textStyle="bold"
                     tools:ignore="HardcodedText,RtlHardcoded"/>
 
+                <TextView
+                    android:id="@+id/playbackSpeed"
+                    android:layout_width="wrap_content"
+                    android:layout_height="wrap_content"
+                    android:layout_marginRight="2dp"
+                    android:layout_toLeftOf="@+id/screenRotationButton"
+                    android:gravity="center"
+                    android:minHeight="35dp"
+                    android:minWidth="40dp"
+                    android:textColor="@android:color/white"
+                    android:textStyle="bold"
+                    tools:ignore="RtlHardcoded,RtlSymmetry"
+                    tools:text="1x" />
+
                 <ImageButton
                     android:id="@+id/screenRotationButton"
                     android:layout_width="35dp"

app/src/main/res/layout/player_popup.xml

@@ -72,6 +72,17 @@
                 android:textStyle="bold"
                 tools:ignore="HardcodedText,RtlHardcoded,RtlSymmetry"/>
 
+            <TextView
+                android:id="@+id/playbackSpeed"
+                android:layout_width="wrap_content"
+                android:layout_height="30dp"
+                android:layout_toRightOf="@id/qualityTextView"
+                android:gravity="center"
+                android:padding="5dp"
+                android:textColor="@android:color/white"
+                tools:ignore="RtlHardcoded,RtlSymmetry"
+                tools:text="1x" />
+
             <ImageButton
                 android:id="@+id/fullScreenButton"
                 android:layout_width="30dp"