android: Add screen recording tool

build/android/pylib/screenshot.py

Index: build/android/pylib/screenshot.py
diff --git a/build/android/pylib/screenshot.py b/build/android/pylib/screenshot.py
new file mode 100644
index 0000000000000000000000000000000000000000..580470c5aca6233c825f49ccb8ff2dd2e30d2bd1
--- /dev/null
+++ b/build/android/pylib/screenshot.py
@@ -0,0 +1,95 @@
+# Copyright (c) 2013 The Chromium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+
+import os
+import time
+
+import android_commands
+import cmd_helper
+
+
+def _GetTimestamp():
+ return time.strftime('%Y-%m-%d-%H%M%S', time.localtime())
+
+
+def _EnsureHostDirectory(host_file):
+  host_dir = os.path.dirname(os.path.abspath(host_file))
+  if not os.path.exists(host_dir):
+    os.makedirs(host_dir)
+
+
+def TakeScreenshot(adb, host_file):
+  """Saves a screenshot image to |host_file| on the host.
+
+  Args:
+    adb: AndroidCommands instance.
+    host_file: Path to the image file to store on the host.
+  """
+  host_file = os.path.abspath(host_file or
+                              'screenshot-%s.png' % _GetTimestamp())
+  _EnsureHostDirectory(host_file)
+  device_file = '%s/screenshot.png' % adb.GetExternalStorage()
+  adb.RunShellCommand('/system/bin/screencap -p %s' % device_file)
+  adb.PullFileFromDevice(device_file, host_file)
+  adb.RunShellCommand('rm -f "%s"' % device_file)
+  return host_file
+
+
+class VideoRecorder(object):
+  """Records a screen capture video from an Android Device (KitKat or newer).
+
+  Args:
+    adb: AndroidCommands instance.
+    host_file: Path to the video file to store on the host.
+    megabits_per_second: Video bitrate in megabits per second. Allowed range
+                         from 0.1 to 100 mbps.
+    size: Video frame size tuple (width, height) or None to use the device
+          default.
+    rotate: If True, the video will be rotated 90 degrees.
+  """
+  def __init__(self, adb, host_file, megabits_per_second=4, size=None,
+               rotate=False):
+    self._adb = adb
+    self._device_file = '%s/screen-recording.mp4' % adb.GetExternalStorage()
+    self._host_file = host_file or 'screen-recording-%s.mp4' % _GetTimestamp()
+    self._host_file = os.path.abspath(self._host_file)
+    self._recorder = None
+    self._recorder_pids = None
+
+    self._args = ['adb']
+    if self._adb.GetDevice():
+      self._args += ['-s', self._adb.GetDevice()]
+    self._args += ['shell', 'screenrecord']
+    self._args += ['--bit-rate', str(megabits_per_second * 1000 * 1000)]
+    if size:
+      self._args += ['--size', '%dx%d' % size]
+    if rotate:
+      self._args += ['--rotate']
+    self._args += [self._device_file]
+
+  def Start(self):
+    """Start recording video."""
+    _EnsureHostDirectory(self._host_file)
+    self._recorder = cmd_helper.Popen(self._args)
+    self._recorder_pids = self._adb.ExtractPid('screenrecord')
+    if not self._recorder_pids:
+      raise RuntimeError('Recording failed. Is your device running Android '
+                         'KitKat or later?')
+
+  def Stop(self):
+    """Stop recording video."""
+    if not self._recorder or not self._recorder_pids:
+      return
+    self._adb.RunShellCommand('kill -SIGINT ' + ' '.join(self._recorder_pids))
+    self._recorder.wait()
+
+  def Pull(self):
+    """Pull resulting video file from the device.
+
+    Returns:
+      Output video file name on the host.
+    """
+    self._adb.PullFileFromDevice(self._device_file, self._host_file)
+    self._adb.RunShellCommand('rm -f "%s"' % self._device_file)
+    return self._host_file