Added missing files

demos/main/src/main/java/com/google/android/exoplayer2/demo/DefaultThumbnailProvider.java

@@ -0,0 +1,194 @@
+package com.google.android.exoplayer2.demo;
+
+import android.graphics.Bitmap;
+import android.graphics.BitmapFactory;
+import android.net.Uri;
+import android.os.AsyncTask;
+import android.util.LruCache;
+import android.view.View;
+import androidx.annotation.Nullable;
+import com.google.android.exoplayer2.ExoPlayer;
+import com.google.android.exoplayer2.source.dash.manifest.DashManifest;
+import com.google.android.exoplayer2.thumbnail.ThumbnailDescription;
+import com.google.android.exoplayer2.util.Log;
+import java.io.InputStream;
+import java.net.HttpURLConnection;
+import java.net.URL;
+import java.util.List;
+
+public class DefaultThumbnailProvider implements ThumbnailProvider {
+
+  private static final String TAG_DEBUG = DefaultThumbnailProvider.class.getSimpleName();
+
+  private LruCache<String, Bitmap> bitmapCache;
+  private View parent;
+
+  //dummy bitmap to indicate that a download is already triggered but not finished yet
+  private final Bitmap dummyBitmap = Bitmap.createBitmap(1,1,Bitmap.Config.ARGB_8888);
+  @Nullable ExoPlayer exoPlayer;
+
+  public DefaultThumbnailProvider(ExoPlayer exoPlayer, View view) {
+    this.exoPlayer = exoPlayer;
+
+    this.parent = view;
+
+    final int maxMemory = (int) (Runtime.getRuntime().maxMemory() / 1024);
+    final int cacheSize = maxMemory / 4;
+    bitmapCache = new LruCache<String, Bitmap>(cacheSize) {
+      @Override
+      protected int sizeOf(String key, Bitmap bitmap) {
+        return bitmap.getByteCount() / 1024;
+      }
+    };
+  }
+
+  public Bitmap getThumbnail(long position) {
+    return getThumbnail(position, true);
+  }
+
+  private Bitmap getThumbnail(long position, boolean retrigger) {
+    if (exoPlayer != null) {
+      Object manifest = exoPlayer.getCurrentManifest();
+
+      ThumbnailDescription thumbnailDescription = null;
+      if (manifest instanceof DashManifest) {
+        DashManifest dashManifest = (DashManifest) manifest;
+        List<ThumbnailDescription> thumbnailDescs = dashManifest.getThumbnailDescriptions(position);
+        //selected thumbnail description with lowest bitrate
+        for (ThumbnailDescription desc : thumbnailDescs) {
+          if (thumbnailDescription == null || thumbnailDescription.getBitrate() > desc.getBitrate()) {
+            thumbnailDescription = desc;
+          }
+        }
+        if (bitmapNotAvailableOrDownloadNotTriggeredYet(thumbnailDescription.getUri())) {
+          this.initThumbnailSource(thumbnailDescription);
+          return null;
+        }
+      }
+
+      if (retrigger) {
+        //also download next and prev thumbnails to have a nicer UI user experience
+        getThumbnail(thumbnailDescription.getStartTimeMs() + thumbnailDescription.getDurationMs(), false);
+        getThumbnail(thumbnailDescription.getStartTimeMs() - thumbnailDescription.getDurationMs(), false);
+      }
+
+      return getThumbnailInternal(position, thumbnailDescription);
+    }
+    return null;
+  }
+
+  private boolean bitmapNotAvailableOrDownloadNotTriggeredYet(Uri uri) {
+    Bitmap tmp = bitmapCache.get(uri.toString());
+    if (tmp != null) return false;
+    return true;
+  }
+
+  private Bitmap getThumbnailInternal(long position, ThumbnailDescription thumbnailDescription) {
+    if (thumbnailDescription == null) return null;
+
+    Bitmap thumbnailSource =  bitmapCache.get(thumbnailDescription.getUri().toString());
+
+    if (thumbnailSource == null || thumbnailSource.getWidth() == 1) return null;
+
+    if (position < thumbnailDescription.getStartTimeMs() || position > thumbnailDescription.getStartTimeMs() + thumbnailDescription.getDurationMs())  return null;
+
+    int count = thumbnailDescription.getColumns() * thumbnailDescription.getRows();
+
+    int durationPerImage = (int)(thumbnailDescription.getDurationMs() / count);
+
+    int imageNumberToUseWithinTile = (int)((position - thumbnailDescription.getStartTimeMs()) / durationPerImage);
+
+    //handle special case if position == duration
+    if (imageNumberToUseWithinTile > count-1) imageNumberToUseWithinTile = count-1;
+
+    int intRowToUse = (int)(imageNumberToUseWithinTile / thumbnailDescription.getColumns());
+
+    int intColToUse = imageNumberToUseWithinTile - intRowToUse * thumbnailDescription.getColumns();
+
+    double thumbnailWidth = (double) thumbnailDescription.getImageWidth() / thumbnailDescription.getColumns();
+    double thumbnailHeight = (double) thumbnailDescription.getImageHeight() / thumbnailDescription.getRows();
+
+    int cropXLeft = (int)Math.round(intColToUse * thumbnailWidth);
+    int cropYTop = (int)Math.round(intRowToUse * thumbnailHeight);
+
+    if (cropXLeft + thumbnailWidth <= thumbnailSource.getWidth() && cropYTop + thumbnailHeight <= thumbnailSource.getHeight()) {
+      return Bitmap.createBitmap(thumbnailSource
+          , cropXLeft, cropYTop, (int) thumbnailWidth, (int) thumbnailHeight);
+    }
+    else {
+      Log.d(TAG_DEBUG, "Image does not have expected (" + thumbnailDescription.getImageWidth() + "x" + thumbnailDescription.getImageHeight() + ") dimensions to crop. Source " + thumbnailDescription.getUri());
+      return null;
+    }
+  }
+
+  private synchronized void initThumbnailSource(ThumbnailDescription thumbnailDescription){
+    String path = thumbnailDescription.getUri().toString();
+    if (path == null) return;
+
+    if (bitmapCache.get(path) != null) return;
+    bitmapCache.put(path, dummyBitmap);
+
+    RetrieveThumbnailImageTask currentTask = new RetrieveThumbnailImageTask();
+    currentTask.executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, path);
+  }
+
+  class RetrieveThumbnailImageTask extends AsyncTask<String, Integer, Bitmap> {
+
+    String downloadedUrl;
+
+    RetrieveThumbnailImageTask() {
+
+    }
+
+    @Override
+    protected void onCancelled() {
+      super.onCancelled();
+      if (downloadedUrl != null) bitmapCache.remove(downloadedUrl);
+    }
+
+    protected Bitmap doInBackground(String... urls) {
+      downloadedUrl = urls[0];
+      InputStream in =null;
+      Bitmap thumbnailToDownload=null;
+      int responseCode = -1;
+
+      try{
+        URL url = new URL(downloadedUrl);
+        if (!isCancelled()) {
+          HttpURLConnection httpURLConnection = (HttpURLConnection)url.openConnection();
+          httpURLConnection.setDoInput(true);
+          httpURLConnection.connect();
+          responseCode = httpURLConnection.getResponseCode();
+          if(responseCode == HttpURLConnection.HTTP_OK)
+          {
+            if (!isCancelled()) {
+              in = httpURLConnection.getInputStream();
+              if (!isCancelled()) {
+                thumbnailToDownload = BitmapFactory.decodeStream(in);
+              }
+              in.close();
+            }
+          }
+        }
+
+      }
+      catch(Exception ex){
+        bitmapCache.remove(downloadedUrl);
+        System.out.println(ex);
+      }
+
+      return thumbnailToDownload;
+    }
+
+    protected void onPostExecute(Bitmap downloadedThumbnail) {
+      if (downloadedThumbnail != null) {
+        bitmapCache.put(downloadedUrl, downloadedThumbnail);
+        if (parent != null) parent.invalidate();
+      }
+      else {
+        bitmapCache.remove(downloadedUrl);
+      }
+    }
+  }
+
+}