class MJPEGStreamer(object):
_httpPort = 8085
def __init__(self, videoDevice, size, fps, format):
self._device = '/dev/video%d' % videoDevice
self._size = size
self._fps = fps
self._format = format
self._videoRunning = False
self._process = None
self._infoArea = cv2.imread(os.path.join(app.static_folder, 'img', 'camera-info-overlay.jpg'), cv2.cv.CV_LOAD_IMAGE_COLOR)
self._infoAreaShape = self._infoArea.shape
#precalculated stuff
watermark = cv2.imread(os.path.join(app.static_folder, 'img', 'astroprint_logo.png'))
watermark = cv2.resize( watermark, ( 100, 100 * watermark.shape[0]/watermark.shape[1] ) )
self._watermarkShape = watermark.shape
watermarkMask = cv2.cvtColor(watermark, cv2.COLOR_BGR2GRAY) / 255.0
watermarkMask = np.repeat( watermarkMask, 3).reshape( (self._watermarkShape[0],self._watermarkShape[1],3) )
self._watermakMaskWeighted = watermarkMask * watermark
self._watermarkInverted = 1.0 - watermarkMask
def startVideo(self):
if not self._process:
command = [
"/mjpeg_streamer/mjpg_streamer",
"-i",
"input_uvc.so -d %s -f %s -r %s --no_dynctrl%s" % (self._device, self._fps, self._size, ' -y' if self._format == 'x-raw' else ''),
"-o",
"output_http.so -p %d" % self._httpPort
]
self._process = Command(command, env={'LD_LIBRARY_PATH': '/mjpeg_streamer'}, stderr=open(os.devnull, 'w'))
if self._process:
self._process.run(async=True)
time.sleep(0.2)
return self._process.returncode is None
return False
def stopVideo(self):
if self._process:
if self._process.returncode is None:
self._process.terminate()
self._process.wait()
self._process = None
def getPhoto(self, text=None, doneCb=None):
image = None
stopAfterPhoto = False
if not self._process:
self.startVideo()
stopAfterPhoto = True
try:
if self._format == 'x-raw':
time.sleep(1.8) # we need to give the camera some time to stabilize the image. 1.8 secs has been tested to work in low end cameras
response = urllib2.urlopen('http://127.0.0.1:%d?action=snapshot' % self._httpPort)
image = response.read()
except urllib2.URLError:
pass
if image and text:
decodedImage = cv2.imdecode(np.fromstring(image, np.uint8), cv2.CV_LOAD_IMAGE_COLOR)
self._apply_watermark(decodedImage, text)
image = cv2.cv.EncodeImage('.jpeg', cv2.cv.fromarray(decodedImage), [cv2.cv.CV_IMWRITE_JPEG_QUALITY, 80]).tostring()
if stopAfterPhoto:
self.stopVideo()
if doneCb:
doneCb(image)
else:
return image
def _apply_watermark(self, img, text):
if text and img != None:
imgPortion = img[-(self._watermarkShape[0]+5):-5, -(self._watermarkShape[1]+5):-5]
img[-(self._watermarkShape[0]+5):-5, -(self._watermarkShape[1]+5):-5] = (self._watermarkInverted * imgPortion) + self._watermakMaskWeighted
img[:self._infoAreaShape[0], :self._infoAreaShape[1]] = self._infoArea
cv2.putText(img, text, (30,17), cv2.FONT_HERSHEY_PLAIN, 1.0, (81,82,241), thickness=1)
return True
return False
class MJPEGStreamer(object):
_httpPort = 8085
def __init__(self, videoDevice, size, fps, format):
self._logger = logging.getLogger(__name__)
self._device = '/dev/video%d' % videoDevice
self._size = size
self._fps = fps
self._format = format
self._videoRunning = False
self._process = None
self._streaming = False
self._needsExposure = True
self._infoArea = cv2.imread(
os.path.join(app.static_folder, 'img', 'camera-info-overlay.jpg'),
cv2.cv.CV_LOAD_IMAGE_COLOR)
self._infoAreaShape = self._infoArea.shape
#precalculated stuff
watermark = cv2.imread(
os.path.join(app.static_folder, 'img', 'astroprint_logo.png'))
watermark = cv2.resize(
watermark, (100, 100 * watermark.shape[0] / watermark.shape[1]))
self._watermarkShape = watermark.shape
watermarkMask = cv2.cvtColor(watermark, cv2.COLOR_BGR2GRAY) / 255.0
watermarkMask = np.repeat(watermarkMask, 3).reshape(
(self._watermarkShape[0], self._watermarkShape[1], 3))
self._watermakMaskWeighted = watermarkMask * watermark
self._watermarkInverted = 1.0 - watermarkMask
def startStreamer(self):
if not self._process:
command = [
"/mjpeg_streamer/mjpg_streamer", "-i",
"input_uvc.so -d %s -f %s -r %s --no_dynctrl%s" %
(self._device, self._fps, self._size,
' -y' if self._format == 'x-raw' else ''), "-o",
"output_http.so -p %d" % self._httpPort
]
self._process = Command(command,
env={'LD_LIBRARY_PATH': '/mjpeg_streamer'},
stderr=open(os.devnull, 'w'))
if self._process:
self._process.run(async=True)
time.sleep(0.2)
running = self._process.returncode is None
return running
return False
def startVideo(self):
if self._streaming:
return True
if self.startStreamer():
self._streaming = True
return True
return False
def stop(self):
if self._process:
if self._process.returncode is None:
self._process.terminate()
tries = 4
while self._process.returncode is None:
if tries > 0:
tries -= 1
time.sleep(0.5)
self._process.poll()
else:
break
if self._process.returncode is None:
self._logger.warn(
'Unable to terminate nicely, killing the process.')
self._process.kill()
self._process.wait()
self._process = None
self._streaming = False
self._needsExposure = True
def stopVideo(self):
self._streaming = False
def isVideoStreaming(self):
return self._streaming
def getPhoto(self, doneCb, text=None):
image = None
if not self._process:
if not self.startStreamer():
self._logger.error('Unable to start MJPEG Streamer')
doneCb(None)
return
try:
if self._needsExposure and not self.isVideoStreaming():
time.sleep(
1.8
) # we need to give the camera some time to stabilize the image. 1.8 secs has been tested to work in low end cameras
self._needsExposure = False
response = urllib2.urlopen('http://127.0.0.1:%d?action=snapshot' %
self._httpPort)
image = response.read()
except urllib2.URLError as e:
self._logger.error(e)
if image and text:
decodedImage = cv2.imdecode(np.fromstring(image, np.uint8),
cv2.CV_LOAD_IMAGE_COLOR)
self._apply_watermark(decodedImage, text)
image = cv2.cv.EncodeImage(
'.jpeg', cv2.cv.fromarray(decodedImage),
[cv2.cv.CV_IMWRITE_JPEG_QUALITY, 80]).tostring()
doneCb(image)
def _apply_watermark(self, img, text):
if text and img != None:
imgPortion = img[-(self._watermarkShape[0] + 5):-5,
-(self._watermarkShape[1] + 5):-5]
img[-(self._watermarkShape[0] + 5):-5,
-(self._watermarkShape[1] +
5):-5] = (self._watermarkInverted *
imgPortion) + self._watermakMaskWeighted
img[:self._infoAreaShape[0], :self.
_infoAreaShape[1]] = self._infoArea
cv2.putText(img,
text, (30, 17),
cv2.FONT_HERSHEY_PLAIN,
1.0, (81, 82, 241),
thickness=1)
return True
return False
class Shell(AbstractContextManager):
"""A real shell running on the host machine, to be used in a context."""
def __init__(self, shell_binary, shell_argstr, return_code_echo_command,
command_separator, is_interactive):
"""Sets up the context for a system shell process.
Parameters
----------
shell_binary : str
The shell binary, e.g. ``/bin/bash``, to start.
shell_argstr : str
Additional arguments to be passed to the shell at start.
return_code_echo_command : str
A command string in the shell's own language that prints to
standard output the return code of the previously executed command.
command_separator : str
The character sequence to separate commands with.
is_interactive : bool
Whether the started shell is an interactive one.
This does only change the behaviour of the context manager, to make
the shell itself interactive, additional arguments in
`shell_argstr` might need to be passed.
"""
self._args = shell_argstr
self._binary = shell_binary
# Note: The execution of the command and the reading of the output
# has to happen BEFORE this timeout is hit, but a large timeout would
# also mean waiting a lot for small commands, so this has to be
# balanced carefully.
self._capture = Capture(timeout=0.5, buffer_size=-1)
self._command = Command(shell_binary + ' ' + shell_argstr,
stdout=self._capture)
self._echo = return_code_echo_command + command_separator
self._interactive = is_interactive
self._separator = command_separator
self._started = False
def __enter__(self):
"""Starts the shell in a context manager setting."""
return self.start()
def __exit__(self, exc_type, exc_value, trace):
"""Destroys the shell and leaves the context."""
if self._interactive:
self.kill()
else:
self.terminate()
return False
def start(self):
"""Starts the underlying shell process as configured in
:py:func:`__init__`.
"""
if self._started:
raise OSError(EEXIST, "The shell is already running!")
print("[Shell] Starting '{0} {1}'...".format(self._binary, self._args),
file=sys.stderr)
try:
self._command.run(input=PIPE, async_=True)
except ValueError:
raise FileNotFoundError("The shell binary '{0}' cannot be found "
"on the system.".format(self._binary))
self._started = True
return self
@property
def pid(self):
"""The PID of the started process."""
if not self._started:
raise OSError(ESRCH, "The shell is not running!")
return self._command.process.pid
def kill(self):
"""Kills (by sending ``SIGKILL`` (``9``)) to the shell process."""
if not self._started:
raise OSError(ESRCH, "The shell is not running!")
self._command.kill()
self._command.wait()
self._capture.close(True)
self._started = False
def terminate(self):
"""Terminates (by sending ``SIGTERM`` (``15``)) to the shell process.
Note
----
Interactive shells (:py:attr:`is_interactive`) usually catch and ignore
this signal, and as such, :py:func:`kill` should be used to shut them
down properly.
"""
if not self._started:
raise OSError(ESRCH, "The shell is not running!")
self._command.terminate()
self._command.wait()
self._capture.close(True)
self._started = False
def execute_command(self, cmd, timeout=None):
"""Execute `cmd` in the shell, wait `timeout` seconds, and read back
the result.
Parameters
----------
cmd : str
The command to execute.
This string will be written into the shell's standard input
verbatim.
timeout : int
The time (in seconds) to wait before the output of the command is
read.
Returns
-------
return_code : int
The return code of the executed command.
result : str
The *standard output* of the executed command.
Note
----
The command executed in the shell is extended with
:py:attr:`command_separator` and :py:attr:`return_code_echo_command`,
and written to the shell.
In case of a conventional ``/bin/bash`` shell, for example, executing
`cmd` ``echo "Foo"`` will actually execute:
.. code-block:: bash
echo "Foo";
echo $;
Which will result in the output:
.. code-block:: bash
Foo
0
to be read as a result.
Warning
-------
The underlying library and the execution of piped shells does not allow
a good method of "sensing" when the output became available while
keeping interactivity.
A too small `timeout` on a loaded system might result in output being
lost, while a too big one will result in every command waiting for
a considerable time.
"""
cmd = cmd + self._separator + self._echo
print("[Shell '{0}'] Running command:\n{1}\n".format(
self._binary,
'\n'.join(list(map(lambda l: " > " + l, cmd.split('\n'))))),
file=sys.stderr)
self._command.stdin.write(cmd.encode('utf-8'))
self._command.stdin.flush()
stdout = self._capture.read(timeout=timeout)
parts = stdout.decode().rstrip().split('\n')
result, returncode = '\n'.join(parts[:-1]).rstrip(), parts[-1].rstrip()
print("[Shell '{0}'] Command result #{1}:\n{2}".format(
self._binary, returncode, result),
file=sys.stderr)
return int(returncode), result