Android: Move CameraStatistics from API to src

webrtc/sdk/android/src/java/org/webrtc/CameraStatistics.java

Index: webrtc/sdk/android/src/java/org/webrtc/CameraStatistics.java
diff --git a/webrtc/sdk/android/src/java/org/webrtc/CameraStatistics.java b/webrtc/sdk/android/src/java/org/webrtc/CameraStatistics.java
new file mode 100644
index 0000000000000000000000000000000000000000..773a2259d915d1cb9a39b04f01424874a58deb1c
--- /dev/null
+++ b/webrtc/sdk/android/src/java/org/webrtc/CameraStatistics.java
@@ -0,0 +1,80 @@
+/*
+ *  Copyright 2017 The WebRTC project authors. All Rights Reserved.
+ *
+ *  Use of this source code is governed by a BSD-style license
+ *  that can be found in the LICENSE file in the root of the source
+ *  tree. An additional intellectual property rights grant can be found
+ *  in the file PATENTS.  All contributing project authors may
+ *  be found in the AUTHORS file in the root of the source tree.
+ */
+
+package org.webrtc;
+
+/**
+ * Helper class to log framerate and detect if the camera freezes. It will run periodic callbacks
+ * on the SurfaceTextureHelper thread passed in the ctor, and should only be operated from that
+ * thread.
+ */
+class CameraStatistics {
+  private final static String TAG = "CameraStatistics";
+  private final static int CAMERA_OBSERVER_PERIOD_MS = 2000;
+  private final static int CAMERA_FREEZE_REPORT_TIMOUT_MS = 4000;
+
+  private final SurfaceTextureHelper surfaceTextureHelper;
+  private final CameraVideoCapturer.CameraEventsHandler eventsHandler;
+  private int frameCount;
+  private int freezePeriodCount;
+  // Camera observer - monitors camera framerate. Observer is executed on camera thread.
+  private final Runnable cameraObserver = new Runnable() {
+    @Override
+    public void run() {
+      final int cameraFps = Math.round(frameCount * 1000.0f / CAMERA_OBSERVER_PERIOD_MS);
+      Logging.d(TAG, "Camera fps: " + cameraFps + ".");
+      if (frameCount == 0) {
+        ++freezePeriodCount;
+        if (CAMERA_OBSERVER_PERIOD_MS * freezePeriodCount >= CAMERA_FREEZE_REPORT_TIMOUT_MS
+            && eventsHandler != null) {
+          Logging.e(TAG, "Camera freezed.");
+          if (surfaceTextureHelper.isTextureInUse()) {
+            // This can only happen if we are capturing to textures.
+            eventsHandler.onCameraFreezed("Camera failure. Client must return video buffers.");
+          } else {
+            eventsHandler.onCameraFreezed("Camera failure.");
+          }
+          return;
+        }
+      } else {
+        freezePeriodCount = 0;
+      }
+      frameCount = 0;
+      surfaceTextureHelper.getHandler().postDelayed(this, CAMERA_OBSERVER_PERIOD_MS);
+    }
+  };
+
+  public CameraStatistics(SurfaceTextureHelper surfaceTextureHelper,
+      CameraVideoCapturer.CameraEventsHandler eventsHandler) {
+    if (surfaceTextureHelper == null) {
+      throw new IllegalArgumentException("SurfaceTextureHelper is null");
+    }
+    this.surfaceTextureHelper = surfaceTextureHelper;
+    this.eventsHandler = eventsHandler;
+    this.frameCount = 0;
+    this.freezePeriodCount = 0;
+    surfaceTextureHelper.getHandler().postDelayed(cameraObserver, CAMERA_OBSERVER_PERIOD_MS);
+  }
+
+  private void checkThread() {
+    if (Thread.currentThread() != surfaceTextureHelper.getHandler().getLooper().getThread()) {
+      throw new IllegalStateException("Wrong thread");
+    }
+  }
+
+  public void addFrame() {
+    checkThread();
+    ++frameCount;
+  }
+
+  public void release() {
+    surfaceTextureHelper.getHandler().removeCallbacks(cameraObserver);
+  }
+}