build/android/pylib/screenshot.py

   1 # Copyright 2013 The Chromium Authors. All rights reserved.
   2 # Use of this source code is governed by a BSD-style license that can be
   3 # found in the LICENSE file.
   4
   5 import os
   6 import signal
   7 import tempfile
   8
   9 from pylib import cmd_helper
  10
  11 # TODO(jbudorick) Remove once telemetry gets switched over.
  12 import pylib.android_commands
  13 import pylib.device.device_utils
  14
  15
  16 class VideoRecorder(object):
  17   """Records a screen capture video from an Android Device (KitKat or newer).
  18
  19   Args:
  20     device: DeviceUtils instance.
  21     host_file: Path to the video file to store on the host.
  22     megabits_per_second: Video bitrate in megabits per second. Allowed range
  23                          from 0.1 to 100 mbps.
  24     size: Video frame size tuple (width, height) or None to use the device
  25           default.
  26     rotate: If True, the video will be rotated 90 degrees.
  27   """
  28   def __init__(self, device, megabits_per_second=4, size=None,
  29                rotate=False):
  30     # TODO(jbudorick) Remove once telemetry gets switched over.
  31     if isinstance(device, pylib.android_commands.AndroidCommands):
  32       device = pylib.device.device_utils.DeviceUtils(device)
  33     self._device = device
  34     self._device_file = (
  35         '%s/screen-recording.mp4' % device.GetExternalStoragePath())
  36     self._recorder = None
  37     self._recorder_stdout = None
  38     self._is_started = False
  39
  40     self._args = ['adb']
  41     if str(self._device):
  42       self._args += ['-s', str(self._device)]
  43     self._args += ['shell', 'screenrecord', '--verbose']
  44     self._args += ['--bit-rate', str(megabits_per_second * 1000 * 1000)]
  45     if size:
  46       self._args += ['--size', '%dx%d' % size]
  47     if rotate:
  48       self._args += ['--rotate']
  49     self._args += [self._device_file]
  50
  51   def Start(self):
  52     """Start recording video."""
  53     self._recorder_stdout = tempfile.mkstemp()[1]
  54     self._recorder = cmd_helper.Popen(
  55         self._args, stdout=open(self._recorder_stdout, 'w'))
  56     if not self._device.GetPids('screenrecord'):
  57       raise RuntimeError('Recording failed. Is your device running Android '
  58                          'KitKat or later?')
  59
  60   def IsStarted(self):
  61     if not self._is_started:
  62       for line in open(self._recorder_stdout):
  63         self._is_started = line.startswith('Content area is ')
  64         if self._is_started:
  65           break
  66     return self._is_started
  67
  68   def Stop(self):
  69     """Stop recording video."""
  70     os.remove(self._recorder_stdout)
  71     self._is_started = False
  72     if not self._recorder:
  73       return
  74     self._device.KillAll('screenrecord', signum=signal.SIGINT)
  75     self._recorder.wait()
  76
  77   def Pull(self, host_file=None):
  78     """Pull resulting video file from the device.
  79
  80     Args:
  81       host_file: Path to the video file to store on the host.
  82     Returns:
  83       Output video file name on the host.
  84     """
  85     host_file_name = host_file or ('screen-recording-%s.mp4' %
  86                                    self._device.old_interface.GetTimestamp())
  87     host_file_name = os.path.abspath(host_file_name)
  88     self._device.old_interface.EnsureHostDirectory(host_file_name)
  89     self._device.PullFile(self._device_file, host_file_name)
  90     self._device.RunShellCommand('rm -f "%s"' % self._device_file)
  91     return host_file_name