Allow log of multiple captures by StreamingCamera

This commit is contained in:
Joel Collins 2018-11-06 18:24:35 +00:00
parent 8031327a5b
commit d99602bd3d
3 changed files with 261 additions and 145 deletions

View file

@ -4,6 +4,7 @@ import io
import threading
import copy
import datetime
import uuid
from PIL import Image
try:
@ -26,43 +27,60 @@ def log(s):
class StreamObject(object):
def __init__(self, write_to_file: bool=None, filename: str=None, folder: str=None, fmt: str='file') -> None:
# Store a nice ID
self.id = filename
self.id = uuid.uuid4().hex
log("Created {}".format(self.id))
# Create file name
self.file = self.build_file_path(filename, folder, fmt)
iterator = 0
f_name = self.build_file_path(filename, folder, fmt)
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
self.file = f_name
# Byte stream properties
self.stream = io.BytesIO() # Byte stream that data will be written to
# Set default write target
self.write_to_file = write_to_file
if self.write_to_file == False:
if self.write_to_file is False:
log("Default target for {} set to 'stream'".format(self.id))
self.target = self.stream
else:
log("Default target for {} set to 'file'".format(self.id))
self.target = self.file
# Keep on disk after close by default
self.keep_on_disk = True
# Object lock
self.locked = False # Is the StreamObject locked for writing? (Handled by StreamingCamera)
def __enter__(self):
log("Entering context for {}. Stored files will be cleaned up automatically.".format(self.id))
log("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.
return self
def __exit__(self, *args):
log("Cleaning up {}".format(self.id))
self.delete()
self.close()
def build_file_path(self, filename: str, folder: str, fmt: str) -> 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
Construct a full file path, based on filename, folder, and file format.
Defaults to datestamp. Iterator adds a numeric increment to the file name.
"""
if filename:
file_name = "{}.{}".format(filename, fmt)
else:
file_name = "{}.{}".format(datetime.datetime.now().strftime("%Y-%m-%d_%H-%M-%S"), fmt)
file_name_base = datetime.datetime.now().strftime("%Y-%m-%d_%H-%M-%S")
if iterator:
file_name_base = "{}_{}".format(file_name_base, iterator)
file_name = "{}.{}".format(file_name_base, fmt)
# Create folder and file
if folder:
@ -76,48 +94,115 @@ class StreamObject(object):
return file_path
def lock(self):
"""Set locked flag to True"""
"""Set locked flag to True."""
self.locked = True
def unlock(self):
"""Set locked flag to False"""
"""Set locked flag to False."""
self.locked = False
@property
def stream_exists(self, auto_rewind=True) -> bool:
"""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
self.stream.seek(0) # Rewind the data bytes for reading
return True
else:
self.stream.seek(0) # Rewind the data bytes for reading
return False
@property
def file_exists(self) -> bool:
"""Check if corresponding file exists"""
if os.path.isfile(self.file):
return True
else:
return False
@property
def metadata(self) -> dict:
d = {
'id': self.id,
'locked': self.locked,
'keep_on_disk': self.keep_on_disk,
'path': self.file,
}
# Get file path
if self.file_exists:
d['file'] = self.file
else:
d['file'] = None
# Check stream
if self.stream_exists:
d['stream'] = True
else:
d['stream'] = False
# Check if file was manually deleted
if self.keep_on_disk and not self.file_exists:
d['path'] = "{} (Deleted)".format(d['path'])
return d
@property
def data(self) -> io.BytesIO:
"""Return a byte string of the capture data"""
"""Return a byte string of the capture data."""
self.stream.seek(0) # Rewind the data bytes for reading
if not self.stream.getvalue() and os.path.isfile(self.file): # If stream is empty but file is not
log("No stream data. Opening from file {}".format(self.file))
with open(self.file, 'rb') as f:
self.stream = io.BytesIO(f.read()) # Load bytes from file in disk
self.stream.seek(0) # Rewind data bytes again
data = self.stream.getbuffer() # Create a copy of the stream bytes
if self.stream_exists: # If data stream contains data
data = io.BytesIO(self.stream.getbuffer()) # Create a copy of the stream bytes
return io.BytesIO(data) # Read and return bytes data
else: # If data stream is empty
if self.file_exists: # If data file exists
# TODO: Streamline this bit
log("No stream data. 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.seek(0) # Rewind loaded stream
data = io.BytesIO(d.getbuffer()) # Create a copy of the stream bytes
else:
data = None
return data # Read and return bytes data
@property
def binary(self) -> bytes:
"""Return a byte string of the capture data"""
"""Return a byte string of the capture data."""
return self.data.getvalue()
def save(self):
"""
Creates/opens a file, and writes this StreamObjects bytestring to the file.
"""
with open(self.file, 'ab') as f: # Load file as bytes
log("Writing stream to file {}".format(self.file))
f.seek(0, 0) # Seek to the start of the file
f.write(self.binary) # Write data bytes to file
def load_file(self) -> bool:
"""Load data stored on disk to the in-memory stream."""
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.seek(0) # Rewind data bytes again
return True
else:
return False
def clear_stream(self):
def save_file(self) -> bool:
"""
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
log("Writing stream to file {}".format(self.file))
f.seek(0, 0) # Seek to the start of the file
f.write(self.binary) # Write data bytes to file
return True
else:
return False
def delete_stream(self):
"""Clears the BytesIO stream of the StreamObject."""
self.stream = io.BytesIO()
return True
def delete(self) -> bool:
def delete_file(self) -> bool:
"""
If the StreamObject has been saved to disk, deletes the file and returns True.
"""
@ -129,6 +214,18 @@ class StreamObject(object):
log("File not found {}".format(self.file))
return False
def shunt(self):
"""Demote the StreamObject from being stored in memory."""
if not self.file_exists: # If file doesn't already exist
self.save_file() # Save stream to disk, if it exists
self.delete_stream() # Delete the stream from memory
def close(self):
"""Both clear the stream, and delete any associated on-disk data"""
self.delete_stream()
if not self.keep_on_disk:
self.delete_file()
class CameraEvent(object):
"""An Event-like class that signals all active clients when a new frame is
@ -181,11 +278,8 @@ class BaseCamera(object):
event = CameraEvent()
def __init__(self):
self.start_worker()
# Stores state of StreamingCamera
self.state = {
}
self.state = {} # Create dict for capture state
self.settings = {} # Create dict to store settings
def start_worker(self, timeout: int=5) -> bool:
"""Start the background camera thread if it isn't running yet."""

View file

@ -53,52 +53,88 @@ HERE = os.path.abspath(os.path.dirname(__file__))
DEFAULT_CONFIG = os.path.join(HERE, 'config_picamera.yaml')
def last_entry(object_list: list):
if object_list: # If any images have been captured
return object_list[-1] # Return the latest captured image
else:
return None
def entry_by_id(id: str, object_list: list):
found = None
for o in object_list:
if o.id == id:
found = o
return found
class StreamingCamera(BaseCamera):
"""Raspberry Pi camera implementation of StreamingCamera."""
def __init__(self):
# Run BaseCamera init to start thread
BaseCamera.__init__(self)
# Capture data
self.image = None
self.video = None
self.images = []
self.videos = []
# Camera settings
self.settings = {
self.settings.update({
'video_resolution': (832, 624),
'image_resolution': (2592, 1944),
'numpy_resolution': (1312, 976),
'jpeg_quality': 75,
}
})
# Store state of StreamingCamera
self.state = {
'video_recent': None,
'image_recent': None,
self.state.update({
'stream_active': False,
'record_active': False,
'preview_active': False,
}
})
# Finally, run BaseCamera init to start thread
BaseCamera.__init__(self)
self.start_worker()
def initialisation(self):
"""Run any initialisation code when the frame iterator starts."""
pass
def start_preview(self) -> bool:
"""Start the onboard GPU camera preview."""
self.start_worker()
# RETURNING CAPTURES
self.camera.start_preview()
self.state['preview_active'] = True
return True
@property
def image(self):
"""Return the latest captured image"""
return last_entry(self.images)
def stop_preview(self) -> bool:
"""Stop the onboard GPU camera preview."""
self.start_worker()
@property
def video(self):
"""Return the latest recorded video"""
return last_entry(self.videos)
self.camera.stop_preview()
self.state['preview_active'] = False
return True
def image_from_id(self, id):
"""Returns 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 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"""
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
target_list.append(stream_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)
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)
# HANDLING SETTINGS
# TODO: Handle exceptions
# TODO: Have this take a dictionary (not a config file)
@ -154,10 +190,10 @@ class StreamingCamera(BaseCamera):
if 'digital_gain' in config:
set_digital_gain(self.camera, config['digital_gain'])
# TODO: Rewrite this bit?
# https://picamera.readthedocs.io/en/release-1.13/api_camera.html
def change_zoom(self, zoom_value: int=1) -> None:
"""Change the camera zoom, handling recentering and scaling."""
self.start_worker()
zoom_value = float(zoom_value)
if zoom_value < 1:
zoom_value = 1
@ -175,26 +211,22 @@ class StreamingCamera(BaseCamera):
new_fov = (centre[0] - size/2, centre[1] - size/2, size, size)
self.camera.zoom = new_fov
def stop_recording(self, target=None) -> bool:
"""Stop the last started video recording on splitter port 2.
# LAUNCH ACTIONS
target (str/BytesIO): Target object to write data bytes to.
"""
if not target: # If no target is defined
target_obj = self.video # Assume StreamingCamera as target
target_obj.unlock() # Unlock the StreamObject
else:
target_obj = target
def start_preview(self) -> bool:
"""Start the onboard GPU camera preview."""
self.start_worker()
# Stop the camera video recording on port 2
log("Stopping recording")
self.camera.stop_recording(splitter_port=2)
log("Recording stopped")
self.camera.start_preview()
self.state['preview_active'] = True
return True
# Update state dictionary
self.state['record_active'] = False
self.state['video_recent'] = str(target_obj)
def stop_preview(self) -> bool:
"""Stop the onboard GPU camera preview."""
self.start_worker()
self.camera.stop_preview()
self.state['preview_active'] = False
return True
def start_recording(
@ -217,47 +249,56 @@ class StreamingCamera(BaseCamera):
fmt (str): Format of the capture.
(default 'h264')
"""
self.start_worker()
# If no target is specified, store to StreamingCamera
if not target:
# If target is not locked
if (self.video is None) or (not self.video.locked):
# Start recording method only if a current recording is not running
if not self.state['record_active']:
self.start_worker()
self.video = StreamObject(
# If no target is specified, store to StreamingCamera
if not target:
# Create a new video and add to the video list
target_obj = self.new_video(StreamObject(
write_to_file=write_to_file,
filename=filename,
folder=folder,
fmt=fmt) # Reset/create StreamObject
fmt=fmt))
# Store to the StreamObject BytesIO
target = self.video.target
# Note the target StreamObject, used for function return
target_obj = self.video
target_obj.lock() # Lock the StreamObject while recording
# Lock the StreamObject while recording
target_obj.lock()
# Store to the StreamObject target
target = target_obj.target
else:
print("Cannot start recording a new video \
until the current recording has been stopped. \
Returning None.")
return None
target_obj = target
# Start the camera video recording on port 2
log("Starting record at {}".format(self.settings['video_resolution']))
self.camera.start_recording(
target,
format=fmt,
splitter_port=2,
resize=self.settings['video_resolution'],
quality=quality)
# Update state dictionary
self.state['record_active'] = True
return target_obj
else:
target_obj = target
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
log("Stopping recording")
self.camera.stop_recording(splitter_port=2)
log("Recording stopped")
# Start the camera video recording on port 2
log("Starting record at {}".format(self.settings['video_resolution']))
self.camera.start_recording(
target,
format=fmt,
splitter_port=2,
resize=self.settings['video_resolution'],
quality=quality)
# Update state dictionary
self.state['record_active'] = True
return target_obj
self.state['record_active'] = False
def pause_stream_for_capture(self, splitter_port: int=1, resolution: Tuple[int, int]=None) -> None:
"""
@ -331,10 +372,9 @@ class StreamingCamera(BaseCamera):
# If no target is specified, store to StreamingCamera
if not target:
self.image = StreamObject(write_to_file=write_to_file, filename=filename, folder=folder, fmt=fmt) # Reset StreamObject
target = self.image.target # Store to the StreamObject BytesIO
target_obj = self.image # Note the target StreamObject, used for function return
# 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 = target_obj.target # Store to the StreamObject BytesIO
else:
target_obj = target
@ -412,6 +452,8 @@ class StreamingCamera(BaseCamera):
else:
return output.array
# HANDLE STREAM FRAMES
def frames(self):
"""
Create iterator used by worker thread to generate stream frames.

View file

@ -10,6 +10,7 @@ import uuid
from PIL import Image
import unittest
from pprint import pprint
success_string = """
/O
@ -40,13 +41,6 @@ class TestCaptureMethods(unittest.TestCase):
for use_video_port in [True, False]:
for resize in [None, (640, 480)]:
# Create unique ID
id = uuid.uuid4().hex
log("Resize: {}, V_Port: {}, ID: {}".format(
resize,
use_video_port,
id))
# Wait for camera
wait_for_cam(camera)
@ -55,11 +49,10 @@ class TestCaptureMethods(unittest.TestCase):
with camera.capture(
write_to_file=False,
use_video_port=use_video_port,
filename=id,
resize=resize) as stream:
# Ensure file deletion fails and returns False
self.assertFalse(stream.delete())
self.assertFalse(stream.delete_file())
# Ensure capture not stored to file
self.assertFalse(os.path.isfile(stream.file))
@ -75,12 +68,12 @@ class TestCaptureMethods(unittest.TestCase):
))
# Save capture to file
stream.save()
stream.save_file()
# Check file got saved
self.assertTrue(os.path.isfile(stream.file))
# Delete file
stream.delete()
stream.delete_file()
# Check file got deleted
self.assertFalse(os.path.isfile(stream.file))
@ -117,9 +110,6 @@ class TestCaptureMethods(unittest.TestCase):
for use_video_port in [True, False]:
for resize in [None, (640, 480)]:
# Create unique ID
id = uuid.uuid4().hex
# Wait for camera
wait_for_cam(camera)
@ -127,7 +117,6 @@ class TestCaptureMethods(unittest.TestCase):
stream = camera.capture(
write_to_file=True,
use_video_port=use_video_port,
filename=id,
resize=resize)
# Check file got saved
@ -141,7 +130,7 @@ class TestCaptureMethods(unittest.TestCase):
self.assertTrue(isinstance(stream.binary, (bytes, bytearray)))
# Ensure file deletion completes and returns True
self.assertTrue(stream.delete())
self.assertTrue(stream.delete_file())
# Check file got deleted
self.assertFalse(os.path.isfile(stream.file))
@ -155,8 +144,6 @@ class TestUnencodedMethods(unittest.TestCase):
for use_video_port in [True, False]:
for resize in [None, (640, 480)]:
# Create unique ID
id = uuid.uuid4().hex
print("{}, {}, {}".format(id, resize, use_video_port))
@ -189,8 +176,6 @@ class TestUnencodedMethods(unittest.TestCase):
for use_video_port in [True, False]:
for resize in [None, (640, 480)]:
# Create unique ID
id = uuid.uuid4().hex
print("{}, {}, {}".format(id, resize, use_video_port))
@ -227,16 +212,12 @@ class TestRecordMethods(unittest.TestCase):
for write_to_file in [True, False, None]:
# Create unique ID
id = uuid.uuid4().hex
# Wait for camera
wait_for_cam(camera)
# Start recording
with camera.start_recording(
write_to_file=write_to_file,
filename=id) as stream:
write_to_file=write_to_file) as stream:
# Record for 2 seconds
time.sleep(2)
@ -264,14 +245,11 @@ class TestRecordMethods(unittest.TestCase):
"""Tests recording videos to file on disk, without context manager."""
global camera
# Create unique ID
id = uuid.uuid4().hex
# Wait for camera
wait_for_cam(camera)
# Start recording
stream = camera.start_recording(filename=id)
stream = camera.start_recording()
# Record for 2 seconds
time.sleep(2)
# Stop recording
@ -282,7 +260,7 @@ class TestRecordMethods(unittest.TestCase):
self.assertTrue(statinfo.st_size > 0)
# Ensure file deletion completes and returns True
self.assertTrue(stream.delete())
self.assertTrue(stream.delete_file())
# Check file got deleted
self.assertFalse(os.path.isfile(stream.file))
@ -293,9 +271,6 @@ class TestThreadStarting(unittest.TestCase):
"""Tests that a capture call restarts the camera worker thread."""
global camera
# Create unique ID
id = uuid.uuid4().hex
# Wait for camera
wait_for_cam(camera)
@ -307,8 +282,7 @@ class TestThreadStarting(unittest.TestCase):
# Restart worker thread by initialising a capture
with camera.capture(
use_video_port=True,
filename=id) as stream:
use_video_port=True) as stream:
# Ensure StreamObject 'stream' has
# a valid BytesIO object and byte string
@ -333,5 +307,11 @@ if __name__ == '__main__':
if result.wasSuccessful():
print(success_string)
# Show us what was captured
for im in camera.images:
pprint(im.metadata)
for im in camera.videos:
pprint(im.metadata)
camera.close()