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diff --git a/examples/android/src/org/appspot/apprtc/FramePool.java b/examples/android/src/org/appspot/apprtc/FramePool.java
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+/*
+ * libjingle
+ * Copyright 2013, Google Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ *  1. Redistributions of source code must retain the above copyright notice,
+ *     this list of conditions and the following disclaimer.
+ *  2. Redistributions in binary form must reproduce the above copyright notice,
+ *     this list of conditions and the following disclaimer in the documentation
+ *     and/or other materials provided with the distribution.
+ *  3. The name of the author may not be used to endorse or promote products
+ *     derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+ * EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+ * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+ * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+ * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+ * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+ * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+package org.appspot.apprtc;
+
+import org.webrtc.VideoRenderer.I420Frame;
+
+import java.util.HashMap;
+import java.util.LinkedList;
+
+/**
+ * This class acts as an allocation pool meant to minimize GC churn caused by
+ * frame allocation & disposal.  The public API comprises of just two methods:
+ * copyFrame(), which allocates as necessary and copies, and
+ * returnFrame(), which returns frame ownership to the pool for use by a later
+ * call to copyFrame().
+ *
+ * This class is thread-safe; calls to copyFrame() and returnFrame() are allowed
+ * to happen on any thread.
+ */
+class FramePool {
+  // Maps each summary code (see summarizeFrameDimensions()) to a list of frames
+  // of that description.
+  private final HashMap<Long, LinkedList<I420Frame>> availableFrames =
+      new HashMap<Long, LinkedList<I420Frame>>();
+  // Every dimension (e.g. width, height, stride) of a frame must be less than
+  // this value.
+  private static final long MAX_DIMENSION = 4096;
+
+  public I420Frame takeFrame(I420Frame source) {
+    long desc = summarizeFrameDimensions(source);
+    I420Frame dst = null;
+    synchronized (availableFrames) {
+      LinkedList<I420Frame> frames = availableFrames.get(desc);
+      if (frames == null) {
+        frames = new LinkedList<I420Frame>();
+        availableFrames.put(desc, frames);
+      }
+      if (!frames.isEmpty()) {
+        dst = frames.pop();
+      } else {
+        dst = new I420Frame(
+            source.width, source.height, source.yuvStrides, null);
+      }
+    }
+    return dst;
+  }
+
+  public void returnFrame(I420Frame frame) {
+    long desc = summarizeFrameDimensions(frame);
+    synchronized (availableFrames) {
+      LinkedList<I420Frame> frames = availableFrames.get(desc);
+      if (frames == null) {
+        throw new IllegalArgumentException("Unexpected frame dimensions");
+      }
+      frames.add(frame);
+    }
+  }
+
+  /** Validate that |frame| can be managed by the pool. */
+  public static boolean validateDimensions(I420Frame frame) {
+    return frame.width < MAX_DIMENSION && frame.height < MAX_DIMENSION &&
+        frame.yuvStrides[0] < MAX_DIMENSION &&
+        frame.yuvStrides[1] < MAX_DIMENSION &&
+        frame.yuvStrides[2] < MAX_DIMENSION;
+  }
+
+  // Return a code summarizing the dimensions of |frame|.  Two frames that
+  // return the same summary are guaranteed to be able to store each others'
+  // contents.  Used like Object.hashCode(), but we need all the bits of a long
+  // to do a good job, and hashCode() returns int, so we do this.
+  private static long summarizeFrameDimensions(I420Frame frame) {
+    long ret = frame.width;
+    ret = ret * MAX_DIMENSION + frame.height;
+    ret = ret * MAX_DIMENSION + frame.yuvStrides[0];
+    ret = ret * MAX_DIMENSION + frame.yuvStrides[1];
+    ret = ret * MAX_DIMENSION + frame.yuvStrides[2];
+    return ret;
+  }
+}