PEP-8-ified code a bit (5df9b53a) · Commits · OpenFlexure / openflexure-microscope-server

openflexure_microscope/camera/base.py

+35 −20

Original line number	Diff line number	Diff line
		@@ -16,6 +16,7 @@ from .capture import StreamObject


		def last_entry(object_list: list):
		"""Return the last entry of a list, if the list contains items."""
		if object_list: # If any images have been captured
		return object_list[-1] # Return the latest captured image
		else:
		@@ -23,6 +24,7 @@ def last_entry(object_list: list):


		def entry_by_id(id: str, object_list: list):
		"""Return an object from a list, if <object>.id matches id argument."""
		found = None
		for o in object_list:
		if o.id == id:
		@@ -31,14 +33,17 @@ def entry_by_id(id: str, object_list: list):


		class CameraEvent(object):
		"""An Event-like class that signals all active clients when a new frame is
		available.
		"""
		def __init__(self):
		"""
		Create a frame-signaller object for StreamingCamera.

		An event-like class that signals all active clients
		when a new frame is available.
		"""
		self.events = {}

		def wait(self, timeout: int=5):
		"""Invoked from each client's thread to wait for the next frame."""
		"""Wait for the next frame (invoked from each client's thread)."""
		ident = get_ident()
		if ident not in self.events:
		# this is a new client
		@@ -48,7 +53,7 @@ class CameraEvent(object):
		return self.events[ident][0].wait(timeout)

		def set(self):
		"""Invoked by the camera thread when a new frame is available."""
		"""Signal that a new frame is available."""
		now = time.time()
		remove = None
		for ident, event in self.events.items():
		@@ -68,7 +73,7 @@ class CameraEvent(object):
		del self.events[remove]

		def clear(self):
		"""Invoked from each client's thread after a frame was processed."""
		"""Clear frame event, once processed."""
		self.events[get_ident()][0].clear()


		@@ -98,7 +103,7 @@ class BaseCamera(object):
		self.close()

		def close(self):
		"""Close the BaseCamera and all attached StreamObjects"""
		"""Close the BaseCamera and all attached StreamObjects."""
		# Close all StreamObjects
		for capture_list in [self.images, self.videos]:
		for stream_object in capture_list:
		@@ -139,14 +144,14 @@ class BaseCamera(object):
		return True

		def stop_worker(self, timeout: int=5) -> bool:
		"""Flags worker thread for stop. Waits for thread to close, or times out."""
		"""Flag worker thread for stop. Waits for thread close or timeout."""
		logging.debug("Stopping worker thread")
		timeout_time = time.time() + timeout

		self.stop = True
		while self.thread:
		if time.time() > timeout_time:
		raise TimeoutError("Timeout waiting for worker thread to close.")
		raise TimeoutError("Timeout waiting for worker thread close.")
		else:
		time.sleep(0)
		return True
		@@ -164,33 +169,37 @@ class BaseCamera(object):
		return self.frame

		def frames(self):
		"""Generator that returns frames from the camera."""
		"""Create generator that returns frames from the camera."""
		raise RuntimeError('Must be implemented by subclasses.')

		# RETURNING CAPTURES

		@property
		def image(self):
		"""Return the latest captured image"""
		"""Return the latest captured image."""
		return last_entry(self.images)

		@property
		def video(self):
		"""Return the latest recorded video"""
		"""Return the latest recorded video."""
		return last_entry(self.videos)

		def image_from_id(self, id):
		"""Returns an image StreamObject with a matching ID"""
		"""Return an image StreamObject with a matching ID."""
		return entry_by_id(id, self.images)

		def video_from_id(self, id):
		"""Returns a video StreamObject with a matching ID"""
		"""Return a video StreamObject with a matching ID."""
		return entry_by_id(id, self.videos)

		# CREATING NEW CAPTURES

		def new_stream_object(self, stream_object, target_list: list, shunt_others: bool=True):
		"""Add a new capture to a list of captures, and shunt all others"""
		def new_stream_object(
		self,
		stream_object,
		target_list: list,
		shunt_others: bool=True):
		"""Add a new capture to a list of captures, and shunt all others."""
		if shunt_others: # If shunting all older captures
		for obj in target_list: # For each older capture
		obj.shunt() # Shunt capture from memory to storage
		@@ -198,12 +207,18 @@ class BaseCamera(object):
		return stream_object

		def new_image(self, stream_object, shunt_others=True):
		"""Add a new capture to the image list, and shunt all others"""
		return self.new_stream_object(stream_object, self.images, shunt_others=shunt_others)
		"""Add a new capture to the image list, and shunt all others."""
		return self.new_stream_object(
		stream_object,
		self.images,
		shunt_others=shunt_others)

		def new_video(self, stream_object, shunt_others=True):
		"""Add a new capture to the video list, and shunt all others"""
		return self.new_stream_object(stream_object, self.videos, shunt_others=shunt_others)
		"""Add a new capture to the video list, and shunt all others."""
		return self.new_stream_object(
		stream_object,
		self.videos,
		shunt_others=shunt_others)

		# WORKER THREAD

openflexure_microscope/camera/capture.py

+42 −24

Original line number	Diff line number	Diff line
		@@ -5,8 +5,15 @@ import datetime
		import copy
		import logging


		class StreamObject(object):
		def __init__(self, write_to_file: bool=None, filename: str=None, folder: str=None, fmt: str='file') -> None:
		def __init__(
		self,
		write_to_file: bool=None,
		filename: str=None,
		folder: str=None,
		fmt: str='file') -> None:
		"""Create a new StreamObject, to manage capture data."""
		# Store a nice ID
		self.id = uuid.uuid4().hex
		logging.info("Created {}".format(self.id))
		@@ -17,7 +24,11 @@ class StreamObject(object):

		while os.path.isfile(f_name): # While file already exists
		iterator += 1 # Add a file name iterator
		f_name = self.build_file_path(filename, folder, fmt, iterator=iterator) # Rebuild file name
		f_name = self.build_file_path(
		filename,
		folder,
		fmt,
		iterator=iterator) # Rebuild file name

		self.file = f_name

		@@ -27,10 +38,10 @@ class StreamObject(object):
		# Set default write target
		self.write_to_file = write_to_file
		if self.write_to_file is False:
		logging.debug("Default target for {} set to 'stream'".format(self.id))
		logging.debug("Target for {} set to 'stream'".format(self.id))
		self.target = self.stream
		else:
		logging.debug("Default target for {} set to 'file'".format(self.id))
		logging.debug("Target for {} set to 'file'".format(self.id))
		self.target = self.file

		# Keep on disk after close by default
		@@ -40,9 +51,10 @@ class StreamObject(object):
		self.context_manager = False

		# Object lock
		self.locked = False # Is the StreamObject locked for writing? (Handled by StreamingCamera)
		self.locked = False

		def __enter__(self):
		"""Create StreamObject in context, to auto-clean disk data."""
		logging.debug("Entering context for {}.\
		Stored files will be cleaned up automatically.".format(self.id))
		self.keep_on_disk = False # Flag file to be removed on close.
		@@ -50,14 +62,21 @@ class StreamObject(object):
		return self

		def __exit__(self, *args):
		"""Exit StreamObject, and auto-clean disk data."""
		logging.info("Cleaning up {}".format(self.id))
		self.close()

		def build_file_path(self, filename: str, folder: str, fmt: str, iterator: int=0) -> str:
		def build_file_path(
		self,
		filename: str,
		folder: str,
		fmt: str,
		iterator: int=0) -> str:
		"""
		Construct a full file path, based on filename, folder, and file format.

		Defaults to datestamp. Iterator adds a numeric increment to the file name.
		Defaults to datestamp.
		Iterator adds a numeric increment to the file name.
		"""
		if filename:
		file_name = "{}.{}".format(filename, fmt)
		@@ -88,7 +107,7 @@ class StreamObject(object):

		@property
		def stream_exists(self, auto_rewind=True) -> bool:
		"""Check if BytesIO stream is empty"""
		"""Check if BytesIO stream is empty."""
		if auto_rewind:
		self.stream.seek(0) # Rewind the data bytes for reading
		if self.stream.getvalue(): # If data stream contains data
		@@ -100,7 +119,7 @@ class StreamObject(object):

		@property
		def file_exists(self) -> bool:
		"""Check if corresponding file exists"""
		"""Check if corresponding file exists."""
		if os.path.isfile(self.file):
		return True
		else:
		@@ -108,6 +127,7 @@ class StreamObject(object):

		@property
		def metadata(self) -> dict:
		"""Return dictionary of StreamObject properties."""
		d = {
		'id': self.id,
		'locked': self.locked,
		@@ -140,16 +160,18 @@ class StreamObject(object):
		self.stream.seek(0) # Rewind the data bytes for reading

		if self.stream_exists: # If data stream contains data
		data = io.BytesIO(self.stream.getbuffer()) # Create a copy of the stream bytes
		# Create a copy of the stream bytes
		data = io.BytesIO(self.stream.getbuffer())

		else: # If data stream is empty
		if self.file_exists: # If data file exists
		# TODO: Streamline this bit
		logging.info("No stream data. Opening from file {}".format(self.file))
		logging.info("Opening from file {}".format(self.file))
		with open(self.file, 'rb') as f:
		d = io.BytesIO(f.read()) # Load bytes from file in disk
		d = io.BytesIO(f.read()) # Load bytes from file
		d.seek(0) # Rewind loaded stream
		data = io.BytesIO(d.getbuffer()) # Create a copy of the stream bytes
		# Create a copy of the stream bytes
		data = io.BytesIO(d.getbuffer())
		else:
		data = None

		@@ -165,16 +187,14 @@ class StreamObject(object):
		if self.file_exists: # If data file exists
		# TODO: Streamline this bit
		with open(self.file, 'rb') as f:
		self.stream = io.BytesIO(f.read()) # Load bytes from file in disk
		self.stream = io.BytesIO(f.read()) # Load bytes from file
		self.stream.seek(0) # Rewind data bytes again
		return True
		else:
		return False

		def save_file(self) -> bool:
		"""
		Write the StreamObjects stream to a file.
		"""
		"""Write the StreamObjects stream to a file."""
		if self.stream_exists: # If there's a stream to save
		with open(self.file, 'ab') as f: # Load file as bytes
		logging.debug("Writing stream to file {}".format(self.file))
		@@ -185,13 +205,11 @@ class StreamObject(object):
		return False

		def delete_stream(self):
		"""Clears the BytesIO stream of the StreamObject."""
		"""Clear the BytesIO stream of the StreamObject."""
		self.stream = io.BytesIO()

		def delete_file(self) -> bool:
		"""
		If the StreamObject has been saved to disk, deletes the file and returns True.
		"""
		"""If the StreamObject has been saved, delete the file."""
		if os.path.isfile(self.file):
		logging.info("Deleting file {}".format(self.file))
		os.remove(self.file)
		@@ -206,7 +224,7 @@ class StreamObject(object):
		self.delete_stream() # Delete the stream from memory

		def close(self):
		"""Both clear the stream, and delete any associated on-disk data"""
		"""Both clear the stream, and delete any associated on-disk data."""
		logging.info("Closing {}".format(self.id))
		self.delete_stream()
		if not self.keep_on_disk:

openflexure_microscope/camera/pi.py

+44 −27

Original line number	Diff line number	Diff line
		@@ -84,7 +84,7 @@ class StreamingCamera(BaseCamera):
		pass

		def close(self):
		"""Close the Raspberry Pi StreamingCamera"""
		"""Close the Raspberry Pi StreamingCamera."""
		# Run BaseCamera close method
		BaseCamera.close(self)
		# Detatch Pi camera
		@@ -135,7 +135,9 @@ class StreamingCamera(BaseCamera):
		if 'awb_mode' in config:
		self.camera.awb_mode = config['awb_mode']
		if 'red_gain' in config and 'blue_gain' in config:
		self.camera.awb_gains = (config['red_gain'], config['blue_gain'])
		self.camera.awb_gains = (
		config['red_gain'],
		config['blue_gain'])

		# Camera framerate
		if 'framerate' in config:
		@@ -158,7 +160,8 @@ class StreamingCamera(BaseCamera):
		self.resume_stream_for_capture()

		else:
		raise Exception("Cannot update camera settings while recording is active.")
		raise Exception(
		"Cannot update camera settings while recording is active.")

		def change_zoom(self, zoom_value: int=1) -> None:
		"""Change the camera zoom, handling recentering and scaling."""
		@@ -213,7 +216,6 @@ class StreamingCamera(BaseCamera):
		fmt (str): Format of the capture.
		(default 'h264')
		"""

		# Start recording method only if a current recording is not running
		if not self.state['record_active']:

		@@ -235,14 +237,14 @@ class StreamingCamera(BaseCamera):
		target_obj = target

		# Start the camera video recording on port 2
		logging.info("Starting record at {}".format(self.settings['video_resolution']))
		logging.info("Recording to {}".format(target))

		self.camera.start_recording(
		target,
		format=fmt,
		splitter_port=2,
		resize=self.settings['video_resolution'],
		quality=quality)
		logging.debug("Recording started successfully.")

		# Update state dictionary
		self.state['record_active'] = True
		@@ -250,12 +252,13 @@ class StreamingCamera(BaseCamera):
		return target_obj

		else:
		print("Cannot start a new recording until the current recording has stopped.")
		print(
		"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)
		@@ -264,7 +267,10 @@ class StreamingCamera(BaseCamera):
		# Update state dictionary
		self.state['record_active'] = False

		def pause_stream_for_capture(self, splitter_port: int=1, resolution: Tuple[int, int]=None) -> None:
		def pause_stream_for_capture(
		self,
		splitter_port: int=1,
		resolution: Tuple[int, int]=None) -> None:
		"""
		Pause capture on a splitter port.

		@@ -283,7 +289,10 @@ class StreamingCamera(BaseCamera):
		# Increase the resolution for taking an image
		self.camera.resolution = resolution

		def resume_stream_for_capture(self, splitter_port: int=1, resolution: Tuple[int, int]=None) -> None:
		def resume_stream_for_capture(
		self,
		splitter_port: int=1,
		resolution: Tuple[int, int]=None) -> None:
		"""
		Resume capture on a splitter port.

		@@ -332,11 +341,14 @@ class StreamingCamera(BaseCamera):
		(default 'h264')
		resize ((int, int)): Resize the captured image.
		"""

		# If no target is specified, store to StreamingCamera
		if not target:
		# Create a new image and add to the image list
		target_obj = self.new_image(StreamObject(write_to_file=write_to_file, filename=filename, folder=folder, fmt=fmt))
		target_obj = self.new_image(StreamObject(
		write_to_file=write_to_file,
		filename=filename,
		folder=folder,
		fmt=fmt))
		target = target_obj.target # Store to the StreamObject BytesIO

		else:
		@@ -373,13 +385,17 @@ class StreamingCamera(BaseCamera):

		return target_obj

		def array(self, rgb=False, use_video_port: bool=True, resize: Tuple[int, int]=None) -> np.ndarray:
		def array(
		self,
		rgb=False,
		use_video_port: bool=True,
		resize: Tuple[int, int]=None) -> np.ndarray:
		"""Capture an uncompressed still YUV image to a Numpy array.

		use_video_port (bool): Capture from the video port used for streaming (lower resolution, faster)
		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.settings['video_resolution']
		else:
		@@ -395,7 +411,8 @@ class StreamingCamera(BaseCamera):

		logging.debug("Creating PiYUVArray")
		with picamera.array.PiYUVArray(self.camera, size=size) as output:
		logging.debug("Capturing to PiYUVArray from {}".format(self.camera))

		logging.info("Capturing to {}".format(output))

		self.camera.capture(
		output,
		@@ -403,8 +420,6 @@ class StreamingCamera(BaseCamera):
		format='yuv',
		use_video_port=use_video_port)

		logging.debug("Capturing complete")

		if not use_video_port:
		self.resume_stream_for_capture()

		@@ -418,10 +433,10 @@ class StreamingCamera(BaseCamera):

		def frames(self):
		"""
		Create iterator used by worker thread to generate stream frames.
		Create generator that returns frames from the camera.

		Holds a Pi camera in context, records video from port 1 to a
		byte stream, and iterates sequential frames.
		Records video from port 1 to a byte stream,
		and iterates sequential frames.
		"""
		# Run this initialisation method
		self.initialisation()
		@@ -447,7 +462,8 @@ class StreamingCamera(BaseCamera):
		logging.debug("STREAM ACTIVE")
		self.state['stream_active'] = True

		try: # While the iterator is not closed
		# While the iterator is not closed
		try:
		while True:
		# reset stream for next frame
		self.stream.seek(0)
		@@ -462,7 +478,8 @@ class StreamingCamera(BaseCamera):
		pass
		else:
		yield frame
		finally: # When GeneratorExit or StopIteration raised, run cleanup code
		# When GeneratorExit or StopIteration raised, run cleanup code
		finally:
		logging.debug("Stopping stream recording on port 1")
		self.camera.stop_recording(splitter_port=1)
		self.state['stream_active'] = False

openflexure_microscope/camera/init.py

+1 −1

File changed.

Contains only whitespace changes.