Implement hardware locks

This commit is contained in:
Joel Collins 2019-01-24 12:11:01 +00:00
parent a40cb9b9f6
commit 8292ebf7c7
10 changed files with 268 additions and 170 deletions

View file

@ -1,4 +1,4 @@
__all__ = ['Microscope', 'config']
__all__ = ['Microscope', 'config', 'task', 'lock']
__version__ = "0.1.0"
from .microscope import Microscope

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@ -23,8 +23,9 @@ from flask_cors import CORS
from openflexure_microscope.api.utilities import list_routes
from openflexure_microscope import Microscope, config
from openflexure_microscope.lock import LockError
from openflexure_microscope.camera.pi import StreamingCamera
from openflexure_stage import OpenFlexureStage
from openflexure_microscope.stage.openflexure import Stage
import atexit
import logging, sys
@ -66,6 +67,16 @@ def _handle_http_exception(e):
for code in default_exceptions:
app.errorhandler(code)(_handle_http_exception)
def _handle_lock_exception(e):
return make_response(
jsonify({
'status_code': 423,
'error': e.code,
'details': e.message
}),
423)
app.errorhandler(LockError)(_handle_lock_exception)
# After app starts, but before first request, attach hardware to global microscope
@app.before_first_request
@ -77,7 +88,7 @@ def attach_microscope():
logging.debug("Creating camera object...")
api_camera = StreamingCamera(config=openflexurerc)
logging.debug("Creating stage object...")
api_stage = OpenFlexureStage("/dev/ttyUSB0")
api_stage = Stage("/dev/ttyUSB0")
logging.debug("Attaching devices to microscope...")
api_microscope.attach(

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@ -19,6 +19,7 @@ except ImportError:
from .capture import CaptureObject, capture_from_dict, BASE_CAPTURE_PATH
from openflexure_microscope.config import USER_CONFIG_DIR
from openflexure_microscope.utilities import entry_by_id
from openflexure_microscope.lock import StrictLock
def last_entry(object_list: list):
@ -29,7 +30,6 @@ def last_entry(object_list: list):
return None
def generate_basename():
"""Return a default filename based on the capture datetime"""
return datetime.datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
@ -87,6 +87,8 @@ class BaseCamera(object):
self.thread = None #: Background thread reading frames from camera
self.camera = None #: Camera object
self.lock = StrictLock(timeout=1) #: Strict lock controlling thread access to camera hardware
self.frame = None #: bytes: Current frame is stored here by background thread
self.last_access = 0 #: time: Time of last client access to the camera
self.event = CameraEvent()

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@ -201,70 +201,73 @@ class StreamingCamera(BaseCamera):
paused_stream = False
# Apply valid config params to Picamera object
if not self.state['record_active']: # If not recording a video
with self.lock:
logging.debug("Applying config:")
logging.debug(config)
# Apply valid config params to Picamera object
if not self.state['record_active']: # If not recording a video
# Pause stream while changing settings
if self.state['stream_active']: # If stream is active
logging.info("Pausing stream to update config.")
self.stop_stream_recording() # Pause stream
paused_stream = True # Remember to unpause stream when done
logging.debug("Applying config:")
logging.debug(config)
# PiCamera parameters (applied directly to PiCamera object)
if 'picamera_params' in config:
for key in PICAMERA_KEYS:
if key in config['picamera_params']:
logging.debug("Setting parameter {}: {}".format(key, config['picamera_params'][key]))
setattr(self.camera, key, config['picamera_params'][key])
# Pause stream while changing settings
if self.state['stream_active']: # If stream is active
logging.info("Pausing stream to update config.")
self.stop_stream_recording() # Pause stream
paused_stream = True # Remember to unpause stream when done
# StreamingCamera parameters (applied via StreamingCamera config)
for key in CONFIG_KEYS:
if key in config:
logging.debug("Setting parameter {}: {}".format(key, config[key]))
self._config[key] = config[key]
# PiCamera parameters (applied directly to PiCamera object)
if 'picamera_params' in config:
for key in PICAMERA_KEYS:
if key in config['picamera_params']:
logging.debug("Setting parameter {}: {}".format(key, config['picamera_params'][key]))
setattr(self.camera, key, config['picamera_params'][key])
# Richard's library to set analog and digital gains
if 'analog_gain' in config:
set_analog_gain(self.camera, config['analog_gain'])
if 'digital_gain' in config:
set_digital_gain(self.camera, config['digital_gain'])
# StreamingCamera parameters (applied via StreamingCamera config)
for key in CONFIG_KEYS:
if key in config:
logging.debug("Setting parameter {}: {}".format(key, config[key]))
self._config[key] = config[key]
# Handle lens shading, if a new one is given
if 'shading_table_path' in config:
self.apply_shading_table()
# Richard's library to set analog and digital gains
if 'analog_gain' in config:
set_analog_gain(self.camera, config['analog_gain'])
if 'digital_gain' in config:
set_digital_gain(self.camera, config['digital_gain'])
# If stream was paused to update config, unpause
if paused_stream:
logging.info("Resuming stream.")
self.start_stream_recording()
# Handle lens shading, if a new one is given
if 'shading_table_path' in config:
self.apply_shading_table()
else:
raise Exception(
"Cannot update camera config while recording is active.")
# If stream was paused to update config, unpause
if paused_stream:
logging.info("Resuming stream.")
self.start_stream_recording()
else:
raise Exception(
"Cannot update camera config while recording is active.")
def set_zoom(self, zoom_value: float=1.) -> None:
"""
Change the camera zoom, handling recentering and scaling.
"""
self.state['zoom_value'] = float(zoom_value)
if self.state['zoom_value'] < 1:
self.state['zoom_value'] = 1
# Richard's code for zooming !
fov = self.camera.zoom
centre = np.array([fov[0] + fov[2]/2.0, fov[1] + fov[3]/2.0])
size = 1.0/self.state['zoom_value']
# If the new zoom value would be invalid, move the centre to
# keep it within the camera's sensor (this is only relevant
# when zooming out, if the FoV is not centred on (0.5, 0.5)
for i in range(2):
if np.abs(centre[i] - 0.5) + size/2 > 0.5:
centre[i] = 0.5 + (1.0 - size)/2 * np.sign(centre[i]-0.5)
logging.info("setting zoom, centre {}, size {}".format(centre, size))
new_fov = (centre[0] - size/2, centre[1] - size/2, size, size)
self.camera.zoom = new_fov
with self.lock:
self.state['zoom_value'] = float(zoom_value)
if self.state['zoom_value'] < 1:
self.state['zoom_value'] = 1
# Richard's code for zooming !
fov = self.camera.zoom
centre = np.array([fov[0] + fov[2]/2.0, fov[1] + fov[3]/2.0])
size = 1.0/self.state['zoom_value']
# If the new zoom value would be invalid, move the centre to
# keep it within the camera's sensor (this is only relevant
# when zooming out, if the FoV is not centred on (0.5, 0.5)
for i in range(2):
if np.abs(centre[i] - 0.5) + size/2 > 0.5:
centre[i] = 0.5 + (1.0 - size)/2 * np.sign(centre[i]-0.5)
logging.info("setting zoom, centre {}, size {}".format(centre, size))
new_fov = (centre[0] - size/2, centre[1] - size/2, size, size)
self.camera.zoom = new_fov
# LAUNCH ACTIONS
@ -299,48 +302,50 @@ class StreamingCamera(BaseCamera):
output_object (str/BytesIO): Target object.
"""
# Start recording method only if a current recording is not running
if not self.state['record_active']:
with self.lock:
# Start recording method only if a current recording is not running
if not self.state['record_active']:
# If output is a StreamObject
if isinstance(output, CaptureObject):
# Lock the StreamObject while recording
output.lock()
# Set target to capture stream
output_stream = output.stream
else:
output_stream = output
# Start the camera video recording on port 2
logging.info("Recording to {}".format(output))
self.camera.start_recording(
output_stream,
format=fmt,
splitter_port=2,
resize=self.config['video_resolution'],
quality=quality)
# Update state dictionary
self.state['record_active'] = True
return output
# If output is a StreamObject
if isinstance(output, CaptureObject):
# Lock the StreamObject while recording
output.lock()
# Set target to capture stream
output_stream = output.stream
else:
output_stream = output
# Start the camera video recording on port 2
logging.info("Recording to {}".format(output))
self.camera.start_recording(
output_stream,
format=fmt,
splitter_port=2,
resize=self.config['video_resolution'],
quality=quality)
# Update state dictionary
self.state['record_active'] = True
return output
else:
logging.error(
"Cannot start a new recording\
until the current recording has stopped.")
return None
logging.error(
"Cannot start a new recording\
until the current recording has stopped.")
return None
def stop_recording(self) -> bool:
"""Stop the last started video recording on splitter port 2."""
# Stop the camera video recording on port 2
logging.info("Stopping recording")
self.camera.stop_recording(splitter_port=2)
logging.info("Recording stopped")
with self.lock:
# Stop the camera video recording on port 2
logging.info("Stopping recording")
self.camera.stop_recording(splitter_port=2)
logging.info("Recording stopped")
# Update state dictionary
self.state['record_active'] = False
# Update state dictionary
self.state['record_active'] = False
def stop_stream_recording(
self,
@ -378,7 +383,6 @@ class StreamingCamera(BaseCamera):
splitter_port (int): Splitter port to start recording on
resolution ((int, int)): Resolution to set the camera to, before starting recording. Defaults to `self.config['video_resolution']`.
"""
# If no stream object exists
if not hasattr(self, 'stream'):
self.stream = io.BytesIO() # Create a stream object
@ -421,32 +425,33 @@ class StreamingCamera(BaseCamera):
resize ((int, int)): Resize the captured image.
"""
# If output is a StreamObject
if isinstance(output, CaptureObject):
# Set target to capture stream
output_stream = output.stream
else:
output_stream = output
with self.lock:
# If output is a StreamObject
if isinstance(output, CaptureObject):
# Set target to capture stream
output_stream = output.stream
else:
output_stream = output
logging.info("Capturing to {}".format(output))
logging.info("Capturing to {}".format(output))
# Set resolution and stop stream recording if necesarry
if not use_video_port:
self.stop_stream_recording()
# Set resolution and stop stream recording if necesarry
if not use_video_port:
self.stop_stream_recording()
self.camera.capture(
output_stream,
format=fmt,
quality=100,
resize=resize,
bayer=(not use_video_port) and bayer,
use_video_port=use_video_port)
self.camera.capture(
output_stream,
format=fmt,
quality=100,
resize=resize,
bayer=(not use_video_port) and bayer,
use_video_port=use_video_port)
# Set resolution and start stream recording if necesarry
if not use_video_port:
self.start_stream_recording()
# Set resolution and start stream recording if necesarry
if not use_video_port:
self.start_stream_recording()
return output
return output
def yuv(
self,
@ -459,38 +464,39 @@ class StreamingCamera(BaseCamera):
use_video_port (bool): Capture from the video port used for streaming. Lower resolution, faster.
resize ((int, int)): Resize the captured image.
"""
if use_video_port:
resolution = self.config['video_resolution']
else:
resolution = self.config['numpy_resolution']
with self.lock:
if use_video_port:
resolution = self.config['video_resolution']
else:
resolution = self.config['numpy_resolution']
if resize:
size = resize
else:
size = resolution
if not use_video_port:
self.stop_stream_recording(resolution=resolution)
logging.debug("Creating PiYUVArray")
with picamera.array.PiYUVArray(self.camera, size=size) as output:
logging.info("Capturing to {}".format(output))
self.camera.capture(
output,
resize=size,
format='yuv',
use_video_port=use_video_port)
if resize:
size = resize
else:
size = resolution
if not use_video_port:
self.start_stream_recording()
self.stop_stream_recording(resolution=resolution)
if rgb:
logging.debug("Converting to RGB")
return output.rgb_array
else:
return output.array
logging.debug("Creating PiYUVArray")
with picamera.array.PiYUVArray(self.camera, size=size) as output:
logging.info("Capturing to {}".format(output))
self.camera.capture(
output,
resize=size,
format='yuv',
use_video_port=use_video_port)
if not use_video_port:
self.start_stream_recording()
if rgb:
logging.debug("Converting to RGB")
return output.rgb_array
else:
return output.array
def array(
self,
@ -502,35 +508,35 @@ class StreamingCamera(BaseCamera):
use_video_port (bool): Capture from the video port used for streaming. Lower resolution, faster.
resize ((int, int)): Resize the captured image.
"""
with self.lock:
if use_video_port:
resolution = self.config['video_resolution']
else:
resolution = self.config['numpy_resolution']
if use_video_port:
resolution = self.config['video_resolution']
else:
resolution = self.config['numpy_resolution']
if resize:
size = resize
else:
size = resolution
if resize:
size = resize
else:
size = resolution
# Always pause stream, to prevent resizer memory issues
self.stop_stream_recording(resolution=resolution)
# Always pause stream, to prevent resizer memory issues
self.stop_stream_recording(resolution=resolution)
logging.debug("Creating PiRGBArray")
with picamera.array.PiRGBArray(self.camera, size=size) as output:
logging.debug("Creating PiRGBArray")
with picamera.array.PiRGBArray(self.camera, size=size) as output:
logging.info("Capturing to {}".format(output))
logging.info("Capturing to {}".format(output))
self.camera.capture(
output,
resize=size,
format='rgb',
use_video_port=use_video_port)
self.camera.capture(
output,
resize=size,
format='rgb',
use_video_port=use_video_port)
# Resume stream
self.start_stream_recording()
# Resume stream
self.start_stream_recording()
return output.array
return output.array
# HANDLE STREAM FRAMES

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@ -0,0 +1,65 @@
from threading import RLock, ThreadError
class LockError(ThreadError):
ERROR_CODES = {
'ACQUIRE_ERROR': "Unable to acquire. Lock in use by another thread.",
'IN_USE_ERROR': "Lock in use by another thread."
}
def __init__(self, code, lock):
self.code = code
if code in LockError.ERROR_CODES:
self.message = LockError.ERROR_CODES[code]
else:
self.message = "Unknown error."
print("{}: {}".format(self.code, self.message))
ThreadError.__init__(self)
class StrictLock(object):
def __init__(self, timeout=1):
self._lock = RLock()
self.timeout = timeout
def acquire(self, blocking=True):
return self._lock.acquire(blocking, timeout=self.timeout)
def __enter__(self):
result = self._lock.acquire(blocking=True, timeout=self.timeout)
if result:
return result
else:
raise LockError('ACQUIRE_ERROR', self)
def __exit__(self, *args):
self._lock.release()
def release(self):
self._lock.release()
class CompositeLock(object):
def __init__(self, locks, timeout=1):
self.locks = locks
self.timeout = timeout
def acquire(self, blocking=True):
return (lock.acquire(blocking=blocking, timeout=self.timeout) for lock in self.locks)
def __enter__(self):
result = (lock.acquire(blocking=True, timeout=self.timeout) for lock in self.locks)
if all(result):
return result
else:
msg = "Unable to acquire all locks {}.".format(self.locks)
logging.error(msg)
raise ThreadError(msg)
def __exit__(self, *args):
for lock in self.locks:
lock.release()
def release(self):
for lock in self.locks:
lock.release()

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@ -67,6 +67,7 @@ class LongRunningAPI(MicroscopeViewPlugin):
# Extract a values from the JSON payload.
time_to_run = payload.param('time', default=10, convert=int)
# Attach the long-running method as a microscope task
try:
task = self.microscope.task.start(self.plugin.long_running, time_to_run)
return jsonify(task.state), 202

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@ -39,10 +39,12 @@ class Plugin(MicroscopePlugin):
print("Starting a long-running task...")
n_array = []
for _ in range(t_run):
n_array.append(random.random())
time.sleep(1)
print("Acquiring camera lock...")
with self.microscope.camera.lock:
for _ in range(t_run):
n_array.append(random.random())
time.sleep(1)
print("Long-running task finished!")
print("Long-running task finished! Releasing lock.")
return n_array

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@ -0,0 +1 @@
from . import openflexure

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@ -0,0 +1,10 @@
from openflexure_stage import OpenFlexureStage
from openflexure_microscope.lock import StrictLock
# TODO: Implement lock on movement
class Stage(OpenFlexureStage):
def __init__(self, *args, **kwargs):
self.lock = StrictLock(timeout=2) #: Strict lock controlling thread access to camera hardware
OpenFlexureStage.__init__(self, *args, **kwargs)

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@ -57,10 +57,10 @@ class TaskOrchestrator:
def start_condition(self, task_obj):
"""
Method returning bool describing if a particular task is allowed to run.
In the future, this will depend on the state of hardware locks?
Currently just allows a single task at a time.
Currently always allows tasks to start, as locks determine access to hardware.
"""
return not any([task._running for task in self.tasks])
#return not any([task._running for task in self.tasks])
return True
class Task: